Sample records for beam calculated flux

  1. URANIUM MILL TAILINGS RADON FLUX CALCULATIONS

    E-Print Network [OSTI]

    URANIUM MILL TAILINGS RADON FLUX CALCULATIONS PIÃ?ON RIDGE PROJECT MONTROSE COUNTY, COLORADO Inc. (Golder) was commissioned by EFRC to evaluate the operations of the uranium mill tailings storage in this report were conducted using the WISE Uranium Mill Tailings Radon Flux Calculator, as updated on November

  2. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-01-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall.

  3. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-06-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall. All of the other model elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.

  4. BROOKHAVEN NATIONAL LABORATORY'S HIGH FLUX BEAM REACTOR

    E-Print Network [OSTI]

    Ohta, Shigemi

    1 BROOKHAVEN NATIONAL LABORATORY'S HIGH FLUX BEAM REACTOR Compiled by S. M. Shapiro I. PICTORIAL with fiberglass insulation and a protective aluminum skin. The reactor vessel is shaped somewhat like a very large at the spherical end. It is located at the center of the reactor building and is surrounded by a lead and steel

  5. Calculation of Neutral Beam Injection into SSPX

    SciTech Connect (OSTI)

    Pearlstein, L D; Casper, T A; Hill, D N; LoDestro, L L; McLean, H S

    2006-06-13T23:59:59.000Z

    The SSPX spheromak experiment has achieved electron temperatures of 350eV and confinement consistent with closed magnetic surfaces. In addition, there is evidence that the experiment may be up against an operational beta limit for Ohmic heating. To test this barrier, there are firm plans to add two 0.9MW Neutral Beam (NB) sources to the experiment. A question is whether the limit is due to instability. Since the deposited Ohmic power in the core is relatively small the additional power from the beams is sufficient to significantly increase the electron temperature. Here we present results of computations that will support this contention. We have developed a new NB module to calculate the orbits of the injected fast fast-ions. The previous computation made heavy use of tokamak ordering which fails for a tight-aspect-ratio device, where B{sub tor} {approx} B{sub pol}. The model calculates the deposition from the NFREYA package [1]. The neutral from the CX deposition is assumed to be ionized in place, a high-density approximation. The fast ions are then assumed to fill a constant angular momentum orbit. And finally, the fast ions immediately assume the form of a dragged down distribution. Transfer rates are then calculated from this distribution function [2]. The differential times are computed from the orbit times and the particle weights in each flux zone (the sampling bin) are proportional to the time spent in the zone. From this information the flux-surface-averaged profiles are obtained and fed into the appropriate transport equation. This procedure is clearly approximate, but accurate enough to help guide experiments. A major advantage is speed: 5000 particles can be processed in under 4s on our fastest LINUX box. This speed adds flexibility by enabling a ''large'' number of predictive studies. Similar approximations, without the accurate orbit calculation presented here, had some success comparing with experiment and TRANSP [3]. Since our procedure does not have multiple CX and relies on disparate time scales, more detailed understanding requires a ''complete'' NB package such as the NUBEAM [4] module, which follows injected fast ions along with their generations until they enter the main thermal distribution.

  6. Integral window/photon beam position monitor and beam flux detectors for x-ray beams

    DOE Patents [OSTI]

    Shu, Deming (Darien, IL); Kuzay, Tuncer M. (Naperville, IL)

    1995-01-01T23:59:59.000Z

    A monitor/detector assembly in a synchrotron for either monitoring the position of a photon beam or detecting beam flux may additionally function as a vacuum barrier between the front end and downstream segment of the beamline in the synchrotron. A base flange of the monitor/detector assembly is formed of oxygen free copper with a central opening covered by a window foil that is fused thereon. The window foil is made of man-made materials, such as chemical vapor deposition diamond or cubic boron nitrate and in certain configurations includes a central opening through which the beams are transmitted. Sensors of low atomic number materials, such as aluminum or beryllium, are laid on the window foil. The configuration of the sensors on the window foil may be varied depending on the function to be performed. A contact plate of insulating material, such as aluminum oxide, is secured to the base flange and is thereby clamped against the sensor on the window foil. The sensor is coupled to external electronic signal processing devices via a gold or silver lead printed onto the contact plate and a copper post screw or alternatively via a copper screw and a copper spring that can be inserted through the contact plate and coupled to the sensors. In an alternate embodiment of the monitor/detector assembly, the sensors are sandwiched between the window foil of chemical vapor deposition diamond or cubic boron nitrate and a front foil made of similar material.

  7. The High Flux Beam Reactor at Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Shapiro, S.M.

    1994-12-31T23:59:59.000Z

    Brookhaven National Laboratory`s High Flux Beam Reactor (HFBR) was built because of the need of the scientist to always want `more`. In the mid-50`s the Brookhaven Graphite reactor was churning away producing a number of new results when the current generation of scientists, led by Donald Hughes, realized the need for a high flux reactor and started down the political, scientific and engineering path that led to the BFBR. The effort was joined by a number of engineers and scientists among them, Chemick, Hastings, Kouts, and Hendrie, who came up with the novel design of the HFBR. The two innovative features that have been incorporated in nearly all other research reactors built since are: (i) an under moderated core arrangement which enables the thermal flux to peak outside the core region where beam tubes can be placed, and (ii) beam tubes that are tangential to the core which decrease the fast neutron background without affecting the thermal beam intensity. Construction began in the fall of 1961 and four years later, at a cost of $12 Million, criticality was achieved on Halloween Night, 1965. Thus began 30 years of scientific accomplishments.

  8. Level 1 Tornado PRA for the High Flux Beam Reactor

    SciTech Connect (OSTI)

    Bozoki, G.E.; Conrad, C.S.

    1994-05-01T23:59:59.000Z

    This report describes a risk analysis primarily directed at providing an estimate for the frequency of tornado induced damage to the core of the High Flux Beam Reactor (HFBR), and thus it constitutes a Level 1 Probabilistic Risk Assessment (PRA) covering tornado induced accident sequences. The basic methodology of the risk analysis was to develop a ``tornado specific`` plant logic model that integrates the internal random hardware failures with failures caused externally by the tornado strike and includes operator errors worsened by the tornado modified environment. The tornado hazard frequency, as well as earlier prepared structural and equipment fragility data, were used as input data to the model. To keep modeling/calculational complexity as simple as reasonable a ``bounding`` type, slightly conservative, approach was applied. By a thorough screening process a single dominant initiating event was selected as a representative initiator, defined as: ``Tornado Induced Loss of Offsite Power.`` The frequency of this initiator was determined to be 6.37E-5/year. The safety response of the HFBR facility resulted in a total Conditional Core Damage Probability of .621. Thus, the point estimate of the HFBR`s Tornado Induced Core Damage Frequency (CDF) was found to be: (CDF){sub Tornado} = 3.96E-5/year. This value represents only 7.8% of the internal CDF and thus is considered to be a small contribution to the overall facility risk expressed in terms of total Core Damage Frequency. In addition to providing the estimate of (CDF){sub Tornado}, the report documents, the relative importance of various tornado induced system, component, and operator failures that contribute most to (CDF){sub Tornado}.

  9. Calculation of Heating Values for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Peterson, Joshua L [ORNL] [ORNL; Ilas, Germina [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments.

  10. Atmospheric neutrino flux calculation using the NRLMSISE00 atmospheric model

    E-Print Network [OSTI]

    Honda, M; Kajita, T; Kasahara, K; Midorikawa, S

    2015-01-01T23:59:59.000Z

    In this paper, we extend the calculation of the atmospheric neutrino flux~\\cite{hkkm2004,hkkms2006,hkkm2011} to the sites in polar and tropical regions. In our earliest full 3D-calculation~\\cite{hkkm2004}, we used DPMJET-III~\\cite{dpm} for the hadronic interaction model above 5~GeV, and NUCRIN~\\cite{nucrin} below 5~GeV. We modified DPMJET-III as in Ref.~\\cite{hkkms2006} to reproduce the experimental muon spectra better, mainly using the data observed by BESS group~\\cite{BESSTeVpHemu}. In a recent work~\\cite{hkkm2011}, we introduced JAM interaction model for the low energy hadronic interactions. JAM is a nuclear interaction model developed with PHITS (Particle and Heavy-Ion Transport code System)~\\cite{phits}. In Ref.~\\cite{hkkm2011}, we could reproduce the observed muon flux at the low energies at balloon altitude with DPMJET-III above 32 GeV and JAM below that better than the combination of DPMJET-III above 5~GeV and NUCRIN below that. Besides the interaction model, we have also improved the calculation sche...

  11. Decommissioning of the high flux beam reactor at Brookhaven Lab

    SciTech Connect (OSTI)

    Hu, J.P. [National Synchrotron Light Source, Brookhaven Laboratory, Upton, NY 11973 (United States); Reciniello, R.N. [Radiological Control Div., Brookhaven Laboratory, Upton, NY 11973 (United States); Holden, N.E. [National Nuclear Data Center, Brookhaven Laboratory, Upton, NY 11973 (United States)

    2011-07-01T23:59:59.000Z

    The high-flux beam reactor (HFBR) at the Brookhaven National Laboratory was a heavy water cooled and moderated reactor that achieved criticality on Oct. 31, 1965. It operated at a power level of 40 megawatts. An equipment upgrade in 1982 allowed operations at 60 megawatts. After a 1989 reactor shutdown to reanalyze safety impact of a hypothetical loss of coolant accident, the reactor was restarted in 1991 at 30 megawatts. The HFBR was shut down in December 1996 for routine maintenance and refueling. At that time, a leak of tritiated water was identified by routine sampling of groundwater from wells located adjacent to the reactor's spent fuel pool. The reactor remained shut down for almost three years for safety and environmental reviews. In November 1999 the United States Dept. of Energy decided to permanently shut down the HFBR. The decontamination and decommissioning of the HFBR complex, consisting of multiple structures and systems to operate and maintain the reactor, were complete in 2009 after removing and shipping off all the control rod blades. The emptied and cleaned HFBR dome, which still contains the irradiated reactor vessel, is presently under 24/7 surveillance for safety. Detailed dosimetry performed for the HFBR decommissioning during 1996-2009 is described in the paper. (authors)

  12. Plasma focus ion beam fluence and flux—For various gases

    SciTech Connect (OSTI)

    Lee, S. [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia) [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia); Physics Department, University of Malaya (Malaysia); Saw, S. H. [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia) [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia)

    2013-06-15T23:59:59.000Z

    A recent paper derived benchmarks for deuteron beam fluence and flux in a plasma focus (PF) [S. Lee and S. H. Saw, Phys. Plasmas 19, 112703 (2012)]. In the present work we start from first principles, derive the flux equation of the ion beam of any gas; link to the Lee Model code and hence compute the ion beam properties of the PF. The results show that, for a given PF, the fluence, flux, ion number and ion current decrease from the lightest to the heaviest gas except for trend-breaking higher values for Ar fluence and flux. The energy fluence, energy flux, power flow, and damage factors are relatively constant from H{sub 2} to N{sub 2} but increase for Ne, Ar, Kr and Xe due to radiative cooling and collapse effects. This paper provides much needed benchmark reference values and scaling trends for ion beams of a PF operated in any gas.

  13. Calculation of conventional and prompt lepton fluxes at very high energy

    E-Print Network [OSTI]

    Fedynitch, Anatoli; Gaisser, Thomas K; Riehn, Felix; Stanev, Todor

    2015-01-01T23:59:59.000Z

    An efficient method for calculating inclusive conventional and prompt atmospheric leptons fluxes is presented. The coupled cascade equations are solved numerically by formulating them as matrix equation. The presented approach is very flexible and allows the use of different hadronic interaction models, realistic parametrizations of the primary cosmic-ray flux and the Earth's atmosphere, and a detailed treatment of particle interactions and decays. The power of the developed method is illustrated by calculating lepton flux predictions for a number of different scenarios.

  14. The Growth of GaN on Si by the Beam Flux Modulation

    SciTech Connect (OSTI)

    Roh, C. H.; Ha, M. W.; Song, H. J.; Choi, H. G.; Lee, J. H.; Ra, Y. W.; Hahn, C. K. [Compound Semiconductor Devices Research Center, Energy-Display R and D Division, Korea Electronics Technology Institute, Seongnam (Korea, Republic of)

    2011-12-23T23:59:59.000Z

    AlGaN/GaN HEMT structure was grown on Si (111) substrate by plasma-assisted molecular beam epitaxy (PA-MBE) using a beam flux modulation methods. In this result, it was verified that the propagation of treading dislocation (TD) due to N-rich GaN layer was effectively suppressed.

  15. Calculation of atmospheric neutrino flux using the interaction model calibrated with atmospheric muon data

    SciTech Connect (OSTI)

    Honda, M.; Kajita, T.; Kasahara, K.; Midorikawa, S.; Sanuki, T

    2007-02-15T23:59:59.000Z

    Using the 'modified DPMJET-III' model explained in the previous paper [T. Sanuki et al., preceding Article, Phys. Rev. D 75, 043005 (2007).], we calculate the atmospheric neutrino flux. The calculation scheme is almost the same as HKKM04 [M. Honda, T. Kajita, K. Kasahara, and S. Midorikawa, Phys. Rev. D 70, 043008 (2004).], but the usage of the 'virtual detector' is improved to reduce the error due to it. Then we study the uncertainty of the calculated atmospheric neutrino flux summarizing the uncertainties of individual components of the simulation. The uncertainty of K-production in the interaction model is estimated using other interaction models: FLUKA'97 and FRITIOF 7.02, and modifying them so that they also reproduce the atmospheric muon flux data correctly. The uncertainties of the flux ratio and zenith angle dependence of the atmospheric neutrino flux are also studied.

  16. Improvement of low energy atmospheric neutrino flux calculation using the JAM nuclear interaction model

    SciTech Connect (OSTI)

    Honda, M.; Kajita, T.; Kasahara, K.; Midorikawa, S. [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan); Institute for Cosmic Ray Research, and Institute for the Physics and Mathematical of the Universe, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan); Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo Shinjuku-ku, Tokyo, 169-8555 (Japan); Faculty of Software and Information Technology, Aomori University, Aomori, 030-0943 Japan (Japan)

    2011-06-15T23:59:59.000Z

    We present the calculation of the atmospheric neutrino fluxes with an interaction model named JAM, which is used in PHITS (Particle and Heavy-Ion Transport code System) [K. Niita et al., Radiation Measurements 41, 1080 (2006).]. The JAM interaction model agrees with the HARP experiment [H. Collaboration, Astropart. Phys. 30, 124 (2008).] a little better than DPMJET-III[S. Roesler, R. Engel, and J. Ranft, arXiv:hep-ph/0012252.]. After some modifications, it reproduces the muon flux below 1 GeV/c at balloon altitudes better than the modified DPMJET-III, which we used for the calculation of atmospheric neutrino flux in previous works [T. Sanuki, M. Honda, T. Kajita, K. Kasahara, and S. Midorikawa, Phys. Rev. D 75, 043005 (2007).][M. Honda, T. Kajita, K. Kasahara, S. Midorikawa, and T. Sanuki, Phys. Rev. D 75, 043006 (2007).]. Some improvements in the calculation of atmospheric neutrino flux are also reported.

  17. INDEPENDENT VERIFICATION SURVEY OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT OUTSIDE AREAS BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-12-15T23:59:59.000Z

    5098-SR-03-0 FINAL REPORT- INDEPENDENT VERIFICATION SURVEY OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT OUTSIDE AREAS, BROOKHAVEN NATIONAL LABORATORY

  18. LETTER REPORT INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT FAN HOUSE, BUILDING 704 BNL

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-10-22T23:59:59.000Z

    5098-LR-01-0 -LETTER REPORT INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT FAN HOUSE, BUILDING 704 BROOKHAVEN NATIONAL LABORATORY

  19. EIS-0291: High Flux Beam Reactor (HFBR) Transition Project at the Brookhaven National Laboratory, Upton, New York

    Broader source: Energy.gov [DOE]

    The EIS evaluates the range of reasonable alternatives and their impacts regarding the future management of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL).

  20. Study of cosmic ray interaction model based on atmospheric muons for the neutrino flux calculation

    SciTech Connect (OSTI)

    Sanuki, T.; Honda, M.; Kajita, T.; Kasahara, K.; Midorikawa, S. [International Center for Elementary Particle Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan); Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570 (Japan); Faculty of Software and Information Technology, Aomori University, 2-3-1 Kobata, Aomori, Aomori 030-0943 (Japan)

    2007-02-15T23:59:59.000Z

    We have studied the hadronic interaction for the calculation of the atmospheric neutrino flux by summarizing the accurately measured atmospheric muon flux data and comparing with simulations. We find the atmospheric muon and neutrino fluxes respond to errors in the {pi}-production of the hadronic interaction similarly, and compare the atmospheric muon flux calculated using the HKKM04 [M. Honda, T. Kajita, K. Kasahara, and S. Midorikawa, Phys. Rev. D 70, 043008 (2004).] code with experimental measurements. The {mu}{sup +}+{mu}{sup -} data show good agreement in the 1{approx}30 GeV/c range, but a large disagreement above 30 GeV/c. The {mu}{sup +}/{mu}{sup -} ratio shows sizable differences at lower and higher momenta for opposite directions. As the disagreements are considered to be due to assumptions in the hadronic interaction model, we try to improve it phenomenologically based on the quark parton model. The improved interaction model reproduces the observed muon flux data well. The calculation of the atmospheric neutrino flux will be reported in the following paper [M. Honda et al., Phys. Rev. D 75, 043006 (2007).].

  1. Uncertainty in calculated surface temperature and surface heat flux of THTF heater rods

    SciTech Connect (OSTI)

    Childs, K.W.

    1980-12-01T23:59:59.000Z

    This report presents a procedure for determining the uncertainty in the output of a complex computer code resulting from uncertainties in its input variables. This method is applied to ORINC (Oak Ridge Inverse Code) to estimate the uncertainty in the calculated surface temperature and surface heat flux of a THTF heater during a blowdown transient. The significant input variables are identified and 95% confidence bands are calculated for the code outputs based on the uncertainty in these input variables. 21 refs., 43 figs.

  2. Uncertainty in calculated surface temperature and surface heat flux of THTF heater rods

    SciTech Connect (OSTI)

    Childs, K.W.

    1980-12-01T23:59:59.000Z

    The report presents a procedure for determining the uncertainty in the output of a complex computer code resulting from uncertainties in its input variables. This method is applied to ORINC (Oak Ridge Inverse Code) to estimate the uncertainty in the calculated surface temperature and surface heat flux of a THTF heater during a blowdown transient. The significant input variables are identified and 95% confidence bands are calculated for the code outputs based on the uncertainty in these input variables.

  3. Analytical calculation of the smear for long-range beam-beam interactions

    E-Print Network [OSTI]

    Kaltchev, D I

    2010-01-01T23:59:59.000Z

    The Lie-algebraic method is used to develop generalized Courant-Snyder invariant in the presence of an arbitrary number of beam-beam collisions, head-on or long-range, in a storage ring collider. The invariant is obtained by concatenating nonlinear beam-beam maps in the horizontal plane and to first order in the beam-beam parameter. Tracking evidence is presented to illustrate that with LHC parameters the invariant is indeed preserved and can be used to predict the smear of horizontal emittance observed in tracking simulations. We discuss the limits of applicability of this model for realistic LHC collision schemes.

  4. TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 2 DF WASTE LINE REMOVAL, BNL

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-07-09T23:59:59.000Z

    5098-SR-02-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 2 DF WASTE LINE REMOVAL, BROOKHAVEN NATIONAL LABORATORY

  5. A new method to calculate the beam charge for an integrating current transformer

    SciTech Connect (OSTI)

    Wu Yuchi; Han Dan; Zhu Bin; Dong Kegong; Tan Fang; Gu Yuqiu [Science and Technology on Plasma Physics Laboratory, Research Center of Laser Fusion, CAEP, Mianyang, Sichuan 621900 (China)

    2012-09-15T23:59:59.000Z

    The integrating current transformer (ICT) is a magnetic sensor widely used to precisely measure the charge of an ultra-short-pulse charged particle beam generated by traditional accelerators and new laser-plasma particle accelerators. In this paper, we present a new method to calculate the beam charge in an ICT based on circuit analysis. The output transfer function shows an invariable signal profile for an ultra-short electron bunch, so the function can be used to evaluate the signal quality and calculate the beam charge through signal fitting. We obtain a set of parameters in the output function from a standard signal generated by an ultra-short electron bunch (about 1 ps in duration) at a radio frequency linear electron accelerator at Tsinghua University. These parameters can be used to obtain the beam charge by signal fitting with excellent accuracy.

  6. PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 1, BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-12-15T23:59:59.000Z

    5098-SR-05-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 1 BROOKHAVEN NATIONAL LABORATORY

  7. PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 5, BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-11-03T23:59:59.000Z

    5098-SR-04-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 5, BROOKHAVEN NATIONAL LABORATORY

  8. Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression

    DOE Patents [OSTI]

    Lasche, G.P.

    1983-09-29T23:59:59.000Z

    The invention is a laser or particle-beam-driven fusion reactor system which takes maximum advantage of both the very short pulsed nature of the energy release of inertial confinement fusion (ICF) and the very small volumes within which the thermonuclear burn takes place. The pulsed nature of ICF permits dynamic direct energy conversion schemes such as magnetohydrodynamic (MHD) generation and magnetic flux compression; the small volumes permit very compact blanket geometries. By fully exploiting these characteristics of ICF, it is possible to design a fusion reactor with exceptionally high power density, high net electric efficiency, and low neutron-induced radioactivity. The invention includes a compact blanket design and method and apparatus for obtaining energy utilizing the compact blanket.

  9. Calculation of thermal fluxes of plasma torch reradiation under the action of laser radiation on a condensed target

    SciTech Connect (OSTI)

    Rudenko, V. V. [Russian Federation Ministry of Defense, 12th Central Scientific Research Institute (Russian Federation)

    2010-12-15T23:59:59.000Z

    The problem of laser deposition with allowance for thermal radiation transport inside and outside the laser torch is considered in a multigroup approximation. The energy fluxes of laser torch thermal radiation onto a target in the far and near zones are calculated as functions of time and the character of the exposure. It is shown that absorption of thermal fluxes in the substrate and target in the course of laser deposition results in their substantial heating. The possibility of diagnosing thermal radiation fluxes from the laser torch by using photodetectors is demonstrated.

  10. A generalized 2D pencil beam scaling algorithm for proton dose calculation in heterogeneous slab geometries

    SciTech Connect (OSTI)

    Westerly, David C. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Mo Xiaohu; DeLuca, Paul M. Jr. [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin 53705 (United States); Tome, Wolfgang A. [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin 53705 and Institute of Onco-Physics, Albert Einstein College of Medicine and Division of Medical Physics, Department of Radiation Oncology, Montefiore Medical Center, Bronx, New York 10461 (United States); Mackie, Thomas R. [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin 53705 and Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin 53792 (United States)

    2013-06-15T23:59:59.000Z

    Purpose: Pencil beam algorithms are commonly used for proton therapy dose calculations. Szymanowski and Oelfke ['Two-dimensional pencil beam scaling: An improved proton dose algorithm for heterogeneous media,' Phys. Med. Biol. 47, 3313-3330 (2002)] developed a two-dimensional (2D) scaling algorithm which accurately models the radial pencil beam width as a function of depth in heterogeneous slab geometries using a scaled expression for the radial kernel width in water as a function of depth and kinetic energy. However, an assumption made in the derivation of the technique limits its range of validity to cases where the input expression for the radial kernel width in water is derived from a local scattering power model. The goal of this work is to derive a generalized form of 2D pencil beam scaling that is independent of the scattering power model and appropriate for use with any expression for the radial kernel width in water as a function of depth. Methods: Using Fermi-Eyges transport theory, the authors derive an expression for the radial pencil beam width in heterogeneous slab geometries which is independent of the proton scattering power and related quantities. The authors then perform test calculations in homogeneous and heterogeneous slab phantoms using both the original 2D scaling model and the new model with expressions for the radial kernel width in water computed from both local and nonlocal scattering power models, as well as a nonlocal parameterization of Moliere scattering theory. In addition to kernel width calculations, dose calculations are also performed for a narrow Gaussian proton beam. Results: Pencil beam width calculations indicate that both 2D scaling formalisms perform well when the radial kernel width in water is derived from a local scattering power model. Computing the radial kernel width from a nonlocal scattering model results in the local 2D scaling formula under-predicting the pencil beam width by as much as 1.4 mm (21%) at the depth of the Bragg peak for a 220 MeV proton beam in homogeneous water. This translates into a 32% dose discrepancy for a 5 mm Gaussian proton beam. Similar trends were observed for calculations made in heterogeneous slab phantoms where it was also noted that errors tend to increase with greater beam penetration. The generalized 2D scaling model performs well in all situations, with a maximum dose error of 0.3% at the Bragg peak in a heterogeneous phantom containing 3 cm of hard bone. Conclusions: The authors have derived a generalized form of 2D pencil beam scaling which is independent of the proton scattering power model and robust to the functional form of the radial kernel width in water used for the calculations. Sample calculations made with this model show excellent agreement with expected values in both homogeneous water and heterogeneous phantoms.

  11. Evaluation of a new commercial Monte Carlo dose calculation algorithm for electron beams

    SciTech Connect (OSTI)

    Vandervoort, Eric J., E-mail: evandervoort@toh.on.ca; Cygler, Joanna E. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada) [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada); The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5 (Canada); Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Tchistiakova, Ekaterina [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada) [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada); Department of Medical Biophysics, University of Toronto, Ontario M5G 2M9 (Canada); Heart and Stroke Foundation Centre for Stroke Recovery, Sunnybrook Research Institute, University of Toronto, Ontario M4N 3M5 (Canada); La Russa, Daniel J. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada) and The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5 (Canada)] [Department of Medical Physics, The Ottawa Hospital Cancer Centre, The University of Ottawa, Ottawa, Ontario K1H 8L6 (Canada) and The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5 (Canada)

    2014-02-15T23:59:59.000Z

    Purpose: In this report the authors present the validation of a Monte Carlo dose calculation algorithm (XiO EMC from Elekta Software) for electron beams. Methods: Calculated and measured dose distributions were compared for homogeneous water phantoms and for a 3D heterogeneous phantom meant to approximate the geometry of a trachea and spine. Comparisons of measurements and calculated data were performed using 2D and 3D gamma index dose comparison metrics. Results: Measured outputs agree with calculated values within estimated uncertainties for standard and extended SSDs for open applicators, and for cutouts, with the exception of the 17 MeV electron beam at extended SSD for cutout sizes smaller than 5 × 5 cm{sup 2}. Good agreement was obtained between calculated and experimental depth dose curves and dose profiles (minimum number of measurements that pass a 2%/2 mm agreement 2D gamma index criteria for any applicator or energy was 97%). Dose calculations in a heterogeneous phantom agree with radiochromic film measurements (>98% of pixels pass a 3 dimensional 3%/2 mm ?-criteria) provided that the steep dose gradient in the depth direction is considered. Conclusions: Clinically acceptable agreement (at the 2%/2 mm level) between the measurements and calculated data for measurements in water are obtained for this dose calculation algorithm. Radiochromic film is a useful tool to evaluate the accuracy of electron MC treatment planning systems in heterogeneous media.

  12. Monte Carlo calculations of electron beam quality conversion factors for several ion chamber types

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: Bryan.Muir@nrc-cnrc.gc.ca [Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6 (Canada); Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 ColonelBy Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2014-11-01T23:59:59.000Z

    Purpose: To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers’ effective point of measurement (EPOM) and beam quality conversion factors. Methods: The EGSnrc system is used for calculations of the absorbed dose to gas in ion chamber models and the absorbed dose to water as a function of depth in a water phantom on which cobalt-60 and several electron beam source models are incident. The optimal EPOM shifts of the ion chambers are determined by comparing calculations of R{sub 50} converted from I{sub 50} (calculated using ion chamber simulations in phantom) to R{sub 50} calculated using simulations of the absorbed dose to water vs depth in water. Beam quality conversion factors are determined as the calculated ratio of the absorbed dose to water to the absorbed dose to air in the ion chamber at the reference depth in a cobalt-60 beam to that in electron beams. Results: For most plane-parallel chambers, the optimal EPOM shift is inside of the active cavity but different from the shift determined with water-equivalent scaling of the front window of the chamber. These optimal shifts for plane-parallel chambers also reduce the scatter of beam quality conversion factors, k{sub Q}, as a function of R{sub 50}. The optimal shift of cylindrical chambers is found to be less than the 0.5 r{sub cav} recommended by current dosimetry protocols. In most cases, the values of the optimal shift are close to 0.3 r{sub cav}. Values of k{sub ecal} are calculated and compared to those from the TG-51 protocol and differences are explained using accurate individual correction factors for a subset of ion chambers investigated. High-precision fits to beam quality conversion factors normalized to unity in a beam with R{sub 50} = 7.5 cm (k{sub Q}{sup ?}) are provided. These factors avoid the use of gradient correction factors as used in the TG-51 protocol although a chamber dependent optimal shift in the EPOM is required when using plane-parallel chambers while no shift is needed with cylindrical chambers. The sensitivity of these results to parameters used to model the ion chambers is discussed and the uncertainty related to the practical use of these results is evaluated. Conclusions: These results will prove useful as electron beam reference dosimetry protocols are being updated. The analysis of this work indicates that cylindrical ion chambers may be appropriate for use in low-energy electron beams but measurements are required to characterize their use in these beams.

  13. Tensile and impact testing of an HFBR (High Flux Beam Reactor) control rod follower

    SciTech Connect (OSTI)

    Czajkowski, C.J.; Schuster, M.H.; Roberts, T.C.; Milian, L.W.

    1989-08-01T23:59:59.000Z

    The Materials Technology Group of the Department of Nuclear Energy (DNE) at Brookhaven National Laboratory (BNL) undertook a program to machine and test specimens from a control rod follower from the High Flux Beam Reactor (HFBR). Tensile and Charpy impact specimens were machined and tested from non-irradiated aluminum alloys in addition to irradiated 6061-T6 from the HFBR. The tensile test results on irradiated material showed a two-fold increase in tensile strength to a maximum of 100.6 ksi. The impact resistance of the irradiated material showed a six-fold decrease in values (3 in-lb average) compared to similar non-irradiated material. Fracture toughness (K{sub I}) specimens were tested on an unirradiated compositionally and dimensionally similar (to HFBR follower) 6061 T-6 material with K{sub max} values of 24.8 {plus minus} 1.0 Ksi{radical}in (average) being obtained. The report concludes that the specimens produced during the program yielded reproducible and believable results and that proper quality assurance was provided throughout the program. 9 figs., 6 tabs.

  14. Monte Carlo calculations for reference dosimetry of electron beams with the PTW Roos and NE2571 ion chambers

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: bmuir@physics.carleton.ca; Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)] [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2013-12-15T23:59:59.000Z

    Purpose: To investigate recommendations for reference dosimetry of electron beams and gradient effects for the NE2571 chamber and to provide beam quality conversion factors using Monte Carlo simulations of the PTW Roos and NE2571 ion chambers. Methods: The EGSnrc code system is used to calculate the absorbed dose-to-water and the dose to the gas in fully modeled ion chambers as a function of depth in water. Electron beams are modeled using realistic accelerator simulations as well as beams modeled as collimated point sources from realistic electron beam spectra or monoenergetic electrons. Beam quality conversion factors are calculated with ratios of the doses to water and to the air in the ion chamber in electron beams and a cobalt-60 reference field. The overall ion chamber correction factor is studied using calculations of water-to-air stopping power ratios. Results: The use of an effective point of measurement shift of 1.55 mm from the front face of the PTW Roos chamber, which places the point of measurement inside the chamber cavity, minimizes the difference betweenR{sub 50}, the beam quality specifier, calculated from chamber simulations compared to that obtained using depth-dose calculations in water. A similar shift minimizes the variation of the overall ion chamber correction factor with depth to the practical range and reduces the root-mean-square deviation of a fit to calculated beam quality conversion factors at the reference depth as a function of R{sub 50}. Similarly, an upstream shift of 0.34 r{sub cav} allows a more accurate determination of R{sub 50} from NE2571 chamber calculations and reduces the variation of the overall ion chamber correction factor with depth. The determination of the gradient correction using a shift of 0.22 r{sub cav} optimizes the root-mean-square deviation of a fit to calculated beam quality conversion factors if all beams investigated are considered. However, if only clinical beams are considered, a good fit to results for beam quality conversion factors is obtained without explicitly correcting for gradient effects. The inadequacy of R{sub 50} to uniquely specify beam quality for the accurate selection of k{sub Q} factors is discussed. Systematic uncertainties in beam quality conversion factors are analyzed for the NE2571 chamber and amount to between 0.4% and 1.2% depending on assumptions used. Conclusions: The calculated beam quality conversion factors for the PTW Roos chamber obtained here are in good agreement with literature data. These results characterize the use of an NE2571 ion chamber for reference dosimetry of electron beams even in low-energy beams.

  15. Progress on the realization of a new GEM based neutron diagnostic concept for high flux neutron beams

    SciTech Connect (OSTI)

    Croci, G.; Tardocchi, M. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano, Italy and INFN, Sez. di Milano-Bicocca, Milano (Italy); Rebai, M.; Cippo, E. Perelli; Gorini, G. [Dipartimento di Fisica, Università degli Studi di Milano-Bicocca, Milano, Italy and INFN, Sez. di Milano-Bicocca, Milano (Italy); Cazzaniga, C. [Dipartimento di Fisica, Università degli Studi di Milano-Bicocca, Milano (Italy); Palma, M. Dalla; Pasqualotto, R.; Tollin, M. [Consorzio RFX - Associazione Euratom-Enea sulla Fusione, Padova (Italy); Grosso, G.; Muraro, A. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, Milano (Italy); Murtas, F.; Claps, G. [INFN, Laboratori Nazionali di Frascati, Frascati (Roma) (Italy); Cavenago, M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy)

    2014-08-21T23:59:59.000Z

    Fusion reactors will need high flux neutron detectors to diagnose the deuterium-deuterium and deuterium-tritium. A candidate detection technique is the Gas Electron Multiplier (GEM). New GEM based detectors are being developed for application to a neutral deuterium beam test facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission due to interaction of the deuterium beam with the deuterons implanted in the beam dump surface. This is done by placing a detector in close contact, right behind the dump. CNESM uses nGEM detectors, i.e. GEM detectors equipped with a cathode that also serves as neutron-proton converter foil. After the realization and test of several small area prototypes, a full size prototype has been realized and tested with laboratory sources. Test on neutron beams are foreseen for the next months.

  16. Calculation of synchrotron radiation from high intensity electron beam at eRHIC

    SciTech Connect (OSTI)

    Jing Y.; Chubar, O.; Litvinenko, V.

    2012-05-20T23:59:59.000Z

    The Electron-Relativistic Heavy Ion Collider (eRHIC) at Brookhaven National Lab is an upgrade project for the existing RHIC. A 30 GeV energy recovery linac (ERL) will provide a high charge and high quality electron beam to collide with proton and ion beams. This will improve the luminosity by at least 2 orders of magnitude. The synchrotron radiation (SR) from the bending magnets and strong quadrupoles for such an intense beam could be penetrating the vacuum chamber and producing hazards to electronic devices and undesired background for detectors. In this paper, we calculate the SR spectral intensity, power density distributions and heat load on the chamber wall. We suggest the wall thickness required to stop the SR and estimate spectral characteristics of the residual and scattered background radiation outside the chamber.

  17. Range and modulation dependencies for proton beam dose per monitor unit calculations

    SciTech Connect (OSTI)

    Hsi, Wen C.; Schreuder, Andries N.; Moyers, Michael F.; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E. [Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); ProCure Treatment Centers, Inc., Bloomington, Indiana 47404 (United States); Proton Therapy, Inc., Colton, California 92324 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and Westdeutsches Protonentherapiezentrum, Universitaetsklinikum, Hufelandstrasse 55, 45147 Essen (Germany); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States)

    2009-02-15T23:59:59.000Z

    Calculations of dose per monitor unit (D/MU) are required in addition to measurements to increase patient safety in the clinical practice of proton radiotherapy. As in conventional photon and electron therapy, the D/MU depends on several factors. This study focused on obtaining range and modulation dependence factors used in D/MU calculations for the double scattered proton beam line at the Midwest Proton Radiotherapy Institute. Three dependencies on range and one dependency on modulation were found. A carefully selected set of measurements was performed to discern these individual dependencies. Dependencies on range were due to: (1) the stopping power of the protons passing through the monitor chamber; (2) the reduction of proton fluence due to nuclear interactions within the patient; and (3) the variation of proton fluence passing through the monitor chamber due to different source-to-axis distances (SADs) for different beam ranges. Different SADs are produced by reconfigurations of beamline elements to provide different field sizes and ranges. The SAD effect on the D/MU varies smoothly as the beam range is varied, except at the beam range for which the first scatterers are exchanged and relocated to accommodate low and high beam ranges. A geometry factor was devised to model the SAD variation effect on the D/MU. The measured D/MU variation as a function of range can be predicted within 1% using the three modeled dependencies on range. Investigation of modulated beams showed that an analytical formula can predict the D/MU dependency as a function of modulation to within 1.5%. Special attention must be applied when measuring the D/MU dependence on modulation to avoid interplay between range and SAD effects.

  18. Hadronic cascade calculations of angular distributions of integrated secondary particle fluxes from external targets and new empirical formulae describing particle production in proton-nucleus collisions

    E-Print Network [OSTI]

    Ranft, J

    1972-01-01T23:59:59.000Z

    Hadronic cascade calculations of angular distributions of integrated secondary particle fluxes from external targets and new empirical formulae describing particle production in proton-nucleus collisions

  19. Thermal rate constant calculation using flux–flux autocorrelation functions: Application to Cl+H2?HCl+H reaction

    E-Print Network [OSTI]

    Wang, Haobin; Thompson, Ward H.; Miller, William H.

    1997-08-01T23:59:59.000Z

    H em m t er re r oy th si This aFˆ ~ b!5e2bH ˆ /2Fˆ e2bH ˆ /2 , ~1.2! which facilitates the evaluation of the trace in Eq. ~1.1b!, and ~2! the fact that the correlation function decays rapidly to zero so that quantum time evolution is required only... for short time. More specifically, ‘‘low rank’’ means that Fˆ (b) has only a relatively small number of eigenvalues that are sig- nificantly different from zero, and the first step of the proce- dure ~vide infra! is a Lanczos iteration calculation to find...

  20. Ray tracing flux calculation for the small and wide angle x-ray scattering diffraction station at the SESAME synchrotron radiation facility

    SciTech Connect (OSTI)

    Salah, Wa'el [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan); Department of Physics, The Hashemite University, Zarqa 13115 (Jordan); Sanchez del Rio, M. [European Synchrotron Radiation Facility, Bp 220, 38043 Grenoble Cedex (France); Hoorani, H. [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan)

    2009-09-15T23:59:59.000Z

    The calculation for the optics of the synchrotron radiation small and wide angle x-ray scattering beamline, currently under construction at SESAME is described. This beamline is based on a cylindrically bent germanium (111) single crystal with an asymmetric cut of 10.5 deg., followed by a 1.2 m long rhodium coated plane mirror bent into a cylindrical form. The focusing properties of bent asymmetrically cut crystals have not yet been studied in depth. The present paper is devoted to study of a particular application of a bent asymmetrically cut crystal using ray tracing simulations with the SHADOW code. These simulations show that photon fluxes of order of 1.09x10{sup 11} photons/s will be available at the experimental focus at 8.79 keV. The focused beam dimensions will be 2.2 mm horizontal full width at half maximum (FWHM) by 0.12 mm vertical (FWHM).

  1. Numerical Calculation of Beam Coupling Impedances in the Frequency Domain using FIT

    E-Print Network [OSTI]

    Niedermayer, U

    2012-01-01T23:59:59.000Z

    The transverse impedance of kicker magnets is considered to be one of the main beam instability sources in the projected SIS-100 at FAIR and also in the SPS at CERN. The longitudinal impedance can contribute to the heat load, which is especially a concern in the cold sections of SIS-100 and LHC. In the high frequency range, commercially available time domain codes like CST Particle Studio serve to calculate the impedance but they are inapplicable at medium and low frequencies which become more important for larger size synchrotrons. We present the ongoing work of developing a Finite Integration Technique (FIT) solver in frequency domain which is based on the Parallel and Extensible Toolkit for Scientific computing (PETSc) framework in C++. Proper beam adapted boundary conditions are important to validate the concept. The code is applied to an inductive insert used to compensate the longitudinal space charge impedance in low energy machines. Another application focuses on the impedance contribution of a ferrit...

  2. Ignition and fueling scenario calculations for neutral-beam-heated Tokamak reactors based on pellet injection

    SciTech Connect (OSTI)

    Lengyel, L.L.

    1986-11-01T23:59:59.000Z

    Results of ignition and continuous fueling scenario calculations are presented that were obtained in the framework of an assessment performed for the Next European Torus based on International Tokamak Reactors (INTOR) parameters. The results obtained with pellet injection are compared with results corresponding to gas puffing. Pellet injection transports fresh fuel to the reaction zone on a time scale that is much shorter than the diffusion time characterizing the gas puffing method, thus making the method flexible and readily adaptable to different situations. In the case of ignition by pellet injection, it may become possible to have deep neutral beam penetration and maintain favorable heat deposition profiles up to the moment of density ramp-up, thus substantially relaxing beam output requirements. The importance of a proper match between beam characteristics and pellet parameters is shown. In the case of continuous fueling of an already ignited discharge, the alpha power production notably increases if repetitive pellet injection, instead of gas puffing, is applied. The advantages of pellet injection are substantial, even at moderate pellet velocities.

  3. Calculating the Loss factor of the LCLS Beam Line Elements for Ultra-Shrot Bunches

    SciTech Connect (OSTI)

    Novokhatski, A.; /SLAC

    2009-10-17T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) is a SASE 1.5-15 {angstrom} x-ray Free-Electron Laser (FEL) facility. Since an ultra-short intense bunch is used in the LCLS operation one might suggest that wake fields, generated in the vacuum chamber, may have an effect on the x-ray production because these fields can change the beam particle energies thereby increasing the energy spread in a bunch. At LCLS a feedback system precisely controls the bunch energy before it enters a beam transport line after the linac. However, in the transport line and later in the undulator section the bunch energy and energy spread are not under feedback control and may change due to wake field radiation, which depends upon the bunch current or on a bunch length. The linear part of the energy spread can be compensated in the upstream linac; the energy loss in the undulator section can be compensated by varying the K-parameter of the undulators, however we need a precise knowledge of the wake fields in this part of the machine. Resistive wake fields are known and well calculated. We discuss an additional part of the wake fields, which comes from the different vacuum elements like bellows, BPMs, transitions, vacuum ports, vacuum valves and others. We use the code 'NOVO' together with analytical estimations for the wake potential calculations.

  4. Compact and high-particle-flux thermal-lithium-beam probe system for measurement of two-dimensional electron density profile

    SciTech Connect (OSTI)

    Shibata, Y., E-mail: shibata.yoshihide@jaea.go.jp; Manabe, T.; Ohno, N.; Takagi, M. [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Kajita, S. [EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Tsuchiya, H.; Morisaki, T. [National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292 (Japan)

    2014-09-15T23:59:59.000Z

    A compact and high-particle-flux thermal-lithium-beam source for two-dimensional measurement of electron density profiles has been developed. The thermal-lithium-beam oven is heated by a carbon heater. In this system, the maximum particle flux of the thermal lithium beam was ?4 × 10{sup 19} m{sup ?2} s{sup ?1} when the temperature of the thermal-lithium-beam oven was 900 K. The electron density profile was evaluated in the small tokamak device HYBTOK-II. The electron density profile was reconstructed using the thermal-lithium-beam probe data and this profile was consistent with the electron density profile measured with a Langmuir electrostatic probe. We confirm that the developed thermal-lithium-beam probe can be used to measure the two-dimensional electron density profile with high time and spatial resolutions.

  5. A Module for Radiation Hydrodynamic Calculations With ZEUS-2D Using Flux-Limited Diffusion

    E-Print Network [OSTI]

    N. J. Turner; J. M. Stone

    2001-02-08T23:59:59.000Z

    A module for the ZEUS-2D code is described which may be used to solve the equations of radiation hydrodynamics to order unity in v/c, in the flux-limited diffusion (FLD) approximation. In this approximation, the tensor Eddington factor f which closes the radiation moment equations is chosen to be an empirical function of radiation energy density. This is easier to implement and faster than full-transport techniques, in which f is computed by solving the transfer equation. However, FLD is less accurate when the flux has a component perpendicular to the gradient in radiation energy density, and in optically thin regions when the radiation field depends strongly on angle. The material component of the fluid is here assumed to be in local thermodynamic equilibrium. The energy equations are operator-split, with transport terms, radiation diffusion term, and other source terms evolved separately. Transport terms are applied using the same consistent transport algorithm as in ZEUS-2D. The radiation diffusion term is updated using an alternating-direction implicit method with convergence checking. Remaining source terms are advanced together implicitly using numerical root-finding. However when absorption opacity is zero, accuracy is improved by treating compression and expansion source terms using time-centered differencing. Results are discussed for test problems including radiation-damped linear waves, radiation fronts propagating in optically-thin media, subcritical and supercritical radiating shocks, and an optically-thick shock in which radiation dominates downstream pressure.

  6. Monte Carlo Method for Calculating Oxygen Abundances and Their Uncertainties from Strong-Line Flux Measurements

    E-Print Network [OSTI]

    Bianco, Federica B; Oh, Seung Man; Fierroz, David; Liu, Yuqian; Kewley, Lisa; Graur, Or

    2015-01-01T23:59:59.000Z

    We present the open-source Python code pyMCZ that determines oxygen abundance and its distribution from strong emission lines in the standard metallicity scales, based on the original IDL code of Kewley & Dopita (2002) with updates from Kewley & Ellison (2008), and expanded to include more recently developed scales. The standard strong-line diagnostics have been used to estimate the oxygen abundance in the interstellar medium through various emission line ratios in many areas of astrophysics, including galaxy evolution and supernova host galaxy studies. We introduce a Python implementation of these methods that, through Monte Carlo (MC) sampling, better characterizes the statistical reddening-corrected oxygen abundance confidence region. Given line flux measurements and their uncertainties, our code produces synthetic distributions for the oxygen abundance in up to 13 metallicity scales simultaneously, as well as for E(B-V), and estimates their median values and their 66% confidence regions. In additi...

  7. Monitor unit calculations for external photon and electron beams: Report of the AAPM Therapy Physics Committee Task Group No. 71

    SciTech Connect (OSTI)

    Gibbons, John P., E-mail: john.gibbons@marybird.com [Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, Louisiana 70809 (United States); Antolak, John A. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota 55905 (United States)] [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Followill, David S. [Department of Radiation Physics, UT M.D. Anderson Cancer Center, Houston, Texas 77030 (United States)] [Department of Radiation Physics, UT M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232 (United States)] [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232 (United States); Klein, Eric E. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States)] [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Lam, Kwok L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States); Palta, Jatinder R. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)] [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Roback, Donald M. [Department of Radiation Oncology, Cancer Centers of North Carolina, Raleigh, North Carolina 27607 (United States)] [Department of Radiation Oncology, Cancer Centers of North Carolina, Raleigh, North Carolina 27607 (United States); Reid, Mark [Department of Medical Physics, Fletcher-Allen Health Care, Burlington, Vermont 05401 (United States)] [Department of Medical Physics, Fletcher-Allen Health Care, Burlington, Vermont 05401 (United States); Khan, Faiz M. [Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota 55455 (United States)] [Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-03-15T23:59:59.000Z

    A protocol is presented for the calculation of monitor units (MU) for photon and electron beams, delivered with and without beam modifiers, for constant source-surface distance (SSD) and source-axis distance (SAD) setups. This protocol was written by Task Group 71 of the Therapy Physics Committee of the American Association of Physicists in Medicine (AAPM) and has been formally approved by the AAPM for clinical use. The protocol defines the nomenclature for the dosimetric quantities used in these calculations, along with instructions for their determination and measurement. Calculations are made using the dose per MU under normalization conditions, D{sub 0}{sup ?}, that is determined for each user's photon and electron beams. For electron beams, the depth of normalization is taken to be the depth of maximum dose along the central axis for the same field incident on a water phantom at the same SSD, where D{sub 0}{sup ?} = 1 cGy/MU. For photon beams, this task group recommends that a normalization depth of 10 cm be selected, where an energy-dependent D{sub 0}{sup ?} ? 1 cGy/MU is required. This recommendation differs from the more common approach of a normalization depth of d{sub m}, with D{sub 0}{sup ?} = 1 cGy/MU, although both systems are acceptable within the current protocol. For photon beams, the formalism includes the use of blocked fields, physical or dynamic wedges, and (static) multileaf collimation. No formalism is provided for intensity modulated radiation therapy calculations, although some general considerations and a review of current calculation techniques are included. For electron beams, the formalism provides for calculations at the standard and extended SSDs using either an effective SSD or an air-gap correction factor. Example tables and problems are included to illustrate the basic concepts within the presented formalism.

  8. Calculation of heat flux through a wall containing a cavity: comparison of several models

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1986-02-01T23:59:59.000Z

    This paper describes the calculation of the heat transfer through the standard stud wall structure of a residential building. The wall cavity contains no insulation. Results from five test cases are presented. The first four represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using an improvement to the Implicit-Compressible Eulerian (ICE) algorithm of Harlow and Amsden. An algorithm is described to efficiently couple the fluid flow calculations to the radiation-conduction model for the solid portions of the system. Results indicate that conduction through still plates contributes less than 2% of the total heat transferred through a composite wall. All of the other elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.

  9. Calculation of beam paths in optical systems containing inhomogeneous isotropic media with cylindrical distribution of the refractive index

    SciTech Connect (OSTI)

    Grammatin, A.P.; Degen, A.B.; Katranova, N.A. [Vavilov State Optical Institute, St. Petersburg (Russian Federation)

    1995-06-01T23:59:59.000Z

    A system of differential equations convenient for numerical computer integrating is proposed to calculate beam paths, elementary astigmatic beams, and the optical path in isotropic media with cylindrical distribution of the refractive index. A method for selecting the step of this integration is proposed. This technique is implemented in the program package for computers of the VAX series meant for the computer-aided design of optical systems. 4 refs.

  10. RELAP5/MOD2. 5 analysis of the HFBR (High Flux Beam Reactor) for a loss of power and coolant accident

    SciTech Connect (OSTI)

    Slovik, G.C.; Rohatgi, U.S.; Jo, Jae.

    1990-05-01T23:59:59.000Z

    A set of postulated accidents were evaluated for the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory. A loss of power accident (LOPA) and a loss of coolant accident (LOCA) were analyzed. This work was performed in response to a DOE review that wanted to update the understanding of the thermal hydraulic behavior of the HFBR during these transients. These calculations were used to determine the margins to fuel damage at the 60 MW power level. The LOPA assumes all the backup power systems fail (although this event is highly unlikely). The reactor scrams, the depressurization valve opens, and the pumps coast down. The HFBR has down flow through the core during normal operation. To avoid fuel damage, the core normally goes through an extended period of forced down flow after a scram before natural circulation is allowed. During a LOPA, the core will go into flow reversal once the buoyancy forces are larger than the friction forces produced during the pump coast down. The flow will stagnate, reverse direction, and establish a buoyancy driven (natural circulation) flow around the core. Fuel damage would probably occur if the critical heat flux (CHF) limit is reached during the flow reversal event. The RELAP5/MOD2.5 code, with an option for heavy water, was used to model the HFBR and perform the LOPA calculation. The code was used to predict the time when the buoyancy forces overcome the friction forces and produce upward directed flow in the core. The Monde CHF correlation and experimental data taken for the HFBR during the design verification phase in 1963 were used to determine the fuel damage margin. 20 refs., 40 figs., 11 tabs.

  11. Angular-divergence calculation for Experimental Advanced Superconducting Tokamak neutral beam injection ion source based on spectroscopic measurements

    SciTech Connect (OSTI)

    Chi, Yuan, E-mail: jtext@hust.edu.cn [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China) [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Hu, Chundong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)] [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Zhuang, Ge [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)] [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-02-15T23:59:59.000Z

    Calorimetric method has been primarily applied for several experimental campaigns to determine the angular divergence of high-current ion source for the neutral beam injection system on the Experimental Advanced Superconducting Tokamak (EAST). A Doppler shift spectroscopy has been developed to provide the secondary measurement of the angular divergence to improve the divergence measurement accuracy and for real-time and non-perturbing measurement. The modified calculation model based on the W7AS neutral beam injectors is adopted to accommodate the slot-type accelerating grids used in the EAST's ion source. Preliminary spectroscopic experimental results are presented comparable to the calorimetrically determined value of theoretical calculation.

  12. Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression

    DOE Patents [OSTI]

    Lasche, G.P.

    1987-02-20T23:59:59.000Z

    A high-power-density-laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems. 25 figs.

  13. Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression

    DOE Patents [OSTI]

    Lasche, George P. (Arlington, VA)

    1988-01-01T23:59:59.000Z

    A high-power-density laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems.

  14. MCNP modeling of the Swiss LWRs for the calculation of the in- and ex-vessel neutron flux distributions

    SciTech Connect (OSTI)

    Pantelias, M.; Volmert, B.; Caruso, S. [National Cooperative for the Disposal of Radioactive Waste Nagra, Hardstrasse 73, 5430, Wettingen (Switzerland); Zvoncek, P. [Laboratory for Nuclear Energy Systems, ETH Zurich, Sonneggstrasse 3, 8092, Zurich (Switzerland); Bitterli, B. [Kernkraftwerk Goesgen-Daeniken AG, 4658 Daeniken (Switzerland); Neukaeter, E.; Nissen, W. [BKW FMB Energie AG-Kernkraftwerk Muehleberg, 3203 Muehleberg (Switzerland); Ledergerber, G. [Kernkraftwerk Leibstadt AG, 5325 Leibstadt (Switzerland); Vielma, R. [Axpo AG-Kernkraftwerk Beznau, 5312 Doettingen (Switzerland)

    2012-07-01T23:59:59.000Z

    MCNP models of all Swiss Nuclear Power Plants have been developed by the National Cooperative for the Disposal of Radioactive Waste (Nagra), in collaboration with the utilities and ETH Zurich, for the 2011 decommissioning cost study. The estimation of the residual radionuclide inventories and corresponding activity levels of irradiated structures and components following the NPP shut-down is of crucial importance for the planning of the dismantling process, the waste packaging concept and, consequently, for the estimation of the decommissioning costs. Based on NPP specific data, the neutron transport simulations lead to the best yet knowledge of the neutron spectra necessary for the ensuing activation calculations. In this paper, the modeling concept towards the MCNP-NPPs is outlined and the resulting flux distribution maps are presented. (authors)

  15. Monte Carlo and Analytical Calculation of Lateral Deflection of Proton Beams in Homogeneous Targets

    SciTech Connect (OSTI)

    Pazianotto, Mauricio T.; Inocente, Guilherme F.; Silva, Danilo Anacleto A. d; Hormaza, Joel M. [Departamento de Fisica e Biofisica-Instituto de Biociencias, Universidade Estadual Paulista 'Julio de Mesquita Filho'-Botucatu-SP, Brasil and Distrito de Rubiao Junior s/no 18608-000 Botucatu, SP (Brazil)

    2010-05-21T23:59:59.000Z

    Proton radiation therapy is a precise form of radiation therapy, but the avoidance of damage to critical normal tissues and the prevention of geographical tumor misses require accurate knowledge of the dose delivered to the patient and the verification of his position demand a precise imaging technique. In proton therapy facilities, the X-ray Computed Tomography (xCT) is the preferred technique for the planning treatment of patients. This situation has been changing nowadays with the development of proton accelerators for health care and the increase in the number of treated patients. In fact, protons could be more efficient than xCT for this task. One essential difficulty in pCT image reconstruction systems came from the scattering of the protons inside the target due to the numerous small-angle deflections by nuclear Coulomb fields. The purpose of this study is the comparison of an analytical formulation for the determination of beam lateral deflection, based on Moliere's theory and Rutherford scattering with Monte Carlo calculations by SRIM 2008 and MCNPX codes.

  16. Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR)

    E-Print Network [OSTI]

    Pennycook, Steve

    Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam Wildgruber, wildgrubercu@ornl.gov. VISION CallforProposals neutrons.ornl.gov Neutron Scattering Science - Oak time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) and Spallation Neutron Source

  17. Beam dynamics in accelerators for medical applications: from calculations to machine performance

    E-Print Network [OSTI]

    components of the electric field U ­ dee voltage N.Hazewindus et al, "The magnetic analogue method as usedin Amplitudes of radial oscillations Vertical beam motion C235 beam acceleration in the central region 13th SAC of radial oscillations versus average radius of the orbits in the near-resonance region AArr initial =1

  18. Effect of flux addition on the microstructure and hardness of TiC-reinforced ferrous surface composite layers fabricated by high-energy electron beam irradiation

    SciTech Connect (OSTI)

    Choo, S.H.; Lee, S.; Kwon, S.J.

    1999-12-01T23:59:59.000Z

    Surface composites reinforced with TiC particulates were fabricated by high-energy electron-beam irradiation. In order to investigate the effects of flux addition on the TiC dispersion in surface composite layers, four kinds of powder mixtures were made by mixing TiC with 5, 10, 20, and 40 wt% of the flux components (MgO-CaO). To fabricate TiC-reinforced surface composites, the TiC-flux mixtures were deposited evenly on a plain carbon steel substrate, which was subjected to electron-beam irradiation. Microstructural analysis was conducted using X-ray diffraction and Moessbauer spectroscopy as well as optical and scanning electron microscopy. The microstructure of the surface composites was composed of a melted region, an interfacial region, a coarse-grained heat-affected zone (HAZ), a fine-grained HAZ, and an unaltered original substrate region. TiC agglomerates and residual pores were found in the melted region of materials processed without flux, but the number of agglomerates and pores are significantly decreased in materials processed with a considerable amount of flux. As a result of irradiation, TiC particles were homogeneously distributed throughout the melted region of 2.5 mm in thickness, whose hardness was greatly increased. The optimum flux amount, which resulted in surface composites containing homogeneously dispersed TiC particles, was found to be in the range of 10 to 20% to obtain excellent surface composites.

  19. An enhanced sector integration model for output and dose distribution calculation of irregular concave shaped electron beams

    SciTech Connect (OSTI)

    Gajewski, Romuald [Department of Medical Physics, Sydney West Cancer Network, Westmead, New South Wales 2145 (Australia)

    2009-07-15T23:59:59.000Z

    A comprehensive method of output factor and dose distribution calculation for electron beams has been developed. It allows one to calculate the output factors and isodose distributions in water of arbitrary shaped electron fields with excellent accuracy even for the cases of concaved, small, elongated beams, and extended source to surface distances (SSDs). The method requires two sets of data: Depth dose distribution per monitor unit for circular cutouts and depth dose distributions per monitor unit for circular blocks (plugs), both for two SSDs, one reference of 100 cm and second extended one. The method has been extensively tested using a combination of different irregular cutouts and various SSDs for the 6 and 9 MeV electron beams. The calculated values agreed with the measured data well within 1% for output factors and below 1 for {gamma} (gamma test) for isodose distributions. The computer program has been developed to facilitate the method for practical application. The method has been used for almost 8 years considerably cutting workload in the department.

  20. Final Report Independent Verification Survey of the High Flux Beam Reactor, Building 802 Fan House Brookhaven National Laboratory Upton, New York

    SciTech Connect (OSTI)

    Harpeneau, Evan M. [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2011-06-24T23:59:59.000Z

    On May 9, 2011, ORISE conducted verification survey activities including scans, sampling, and the collection of smears of the remaining soils and off-gas pipe associated with the 802 Fan House within the HFBR (High Flux Beam Reactor) Complex at BNL. ORISE is of the opinion, based on independent scan and sample results obtained during verification activities at the HFBR 802 Fan House, that the FSS (final status survey) unit meets the applicable site cleanup objectives established for as left radiological conditions.

  1. On the “direct” calculation of thermal rate constants. II. The flux-flux autocorrelation function with absorbing potentials, with application to the O+HCl?OH+Cl reaction

    E-Print Network [OSTI]

    Thompson, Ward H.; Miller, William H.

    1997-01-01T23:59:59.000Z

    value of J and K . In practice, though, things are greatly simplified because the dependence of kJK on J and K is very simple. For example, if the J-shifting approximation were accurate, then Eq. ~3.3! shows the J and K dependence is ln kJK~T !5constant2... of the Boltzmannized flux operator used to cal- culate the trace! at T5400 K. FIG. 5. The partial rate constant kJK ~within the helicity conserving approxi- mation! vs J(J11) for K50. Results for T5400 K ~solid line with circles! and T5250 K ~dashed line with squares...

  2. SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3: TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-11-15T23:59:59.000Z

    5098-LR-02-0 SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3 TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY

  3. Calculational analysis of structural activation induced by 20-100 MeV proton beam loss in high-power linear accelerators

    E-Print Network [OSTI]

    Lee, Stacey Kirsten

    1994-01-01T23:59:59.000Z

    fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1994 Major Subject: Nuclear Engineering CALCULATIONAL ANALYSIS OF STRUCTURAL ACTIVATION INDUCED BY 20-100 MEV PROTON BEAM LOSS IN HIGH-POWER LINEAR ACCELERATORS A Thesis...) Carl A. Beard (Member) / John . Poston (Head of Department) August 1994 Major Subject: Nuclear Engineering ABSTRACT Calculational Analysis of Structural Activation Induced by 20-100 MeV Proton Beam Loss in High-Power Linear Accelerators. (August...

  4. Dose calculations using MARS for Bremsstrahlung beam stops and collimators in APS beamline stations.

    SciTech Connect (OSTI)

    Dooling, J.; Accelerator Systems Division (APS)

    2010-11-01T23:59:59.000Z

    The Monte Carlo radiation transport code MARS is used to model the generation of gas bremsstrahlung (GB) radiation from 7-GeV electrons which scatter from residual gas atoms in undulator straight sections within the Advanced Photon Source (APS) storage ring. Additionally, MARS is employed to model the interactions of the GB radiation with components along the x-ray beamlines and then determine the expected radiation dose-rates that result. In this manner, MARS can be used to assess the adequacy of existing shielding or the specifications for new shielding when required. The GB radiation generated in the 'thin-target' of an ID straight section will consist only of photons in a 1/E-distribution up to the full energy of the stored electron beam. Using this analytical model, the predicted GB power for a typical APS 15.38-m insertion device (ID) straight section is 4.59 x 10{sup -7} W/nTorr/mA, assuming a background gas composed of air (Z{sub eff} = 7.31) at room temperature (293K). The total GB power provides a useful benchmark for comparisons between analytical and numerical approaches. We find good agreement between MARS and analytical estimates for total GB power. The extended straight section 'target' creates a radial profile of GB, which is highly peaked centered on the electron beam. The GB distribution reflects the size of the electron beam that creates the radiation. Optimizing the performance of MARS in terms of CPU time per incident trajectory requires the use of a relatively short, high-density gas target (air); in this report, the target density is {rho}L = 2.89 x 10{sup -2} g/cm{sup 2} over a length of 24 cm. MARS results are compared with the contact dose levels reported in TB-20, which used EGS4 for radiation transport simulations. Maximum dose-rates in 1 cc of tissue phantom form the initial basis for comparison. MARS and EGS4 results are approximately the same for maximum 1-cc dose-rates and attenuation in the photon-dominated regions; for thicker targets, however, the dose-rate no longer depends only on photon attenuation, as photoneutrons (PNs) begin to dominate. The GB radiation-induced photoneutron measurements from four different metals (Fe, Cu, W, and Pb) are compared with MARS predictions. The simulated dose-rates for beamline 6-ID are approximately 3-5 times larger than the measured values, whereas those for beamline 11-ID are much closer. Given the uncertainty in local values of pressure and Z, the degree of agreement between MARS and the PN measurements is good. MARS simulations of GB-induced radiation in and around the FOE show the importance of using actual pressure and gas composition (Z{sub eff}) to obtain accurate PN dose. For a beam current of 300 mA, extrapolating pressure data measured in previously published studies predicts an average background gas pressure of 27 nTorr. An average atomic number of Z{sub eff} = 4.0 is obtained from the same studies. In addition, models of copper masks presently in use at the APS are included. Simulations show that inclusion of exit masks make significant differences in both the radiation spatial distribution within the FOE, as well as the peak intensity. Two studies have been conducted with MARS to assess shielding requirements. First, dose levels in contact with the outside wall of the FOE are examined when GB radiation strikes Pb or W beam stops of varying transverse size within the FOE. Four separate phantom regions are utilized to measure the dose, two at beam elevation and two at the horizontal beam position. The first two phantoms are used for scoring FOE dose along the outside and back walls, horizontally; the second two collect dose on the roof and vertically on the back wall. In all cases, the beam stop depth is maintained at 30 cm. Inclusion of front end (FE) exit masks typically cause a 1-2 order-of-magnitude increase in the dose-rates relative to the case with no masks. Masks place secondary bremsstrahlung sources inside the FOE, and therefore they must be shielded appropriately. The MARS model does not fully account for all shielding present

  5. Effect of aerosols and NO2 concentration on ultraviolet actinic flux near Mexico City during MILAGRO: Measurements and model calculations

    SciTech Connect (OSTI)

    Palancar, Gustavo G.; Lefer, Barry; Hall, Samual R.; Shaw, William J.; Corr, Chelsea A.; Herndon, Scott C.; Slusser, J. R.; Madronich, Sasha

    2013-01-24T23:59:59.000Z

    Ultraviolet (UV) actinic ?uxes (AF) measured with three Scanning Actinic Flux Spectroradiometers (SAFS) are compared with the Tropospheric Ultraviolet-Visible (TUV) model v.5 in order to assess the effects of aerosols and NO2 concentrations on the radiation. Measurements were made during the MILAGRO campaign near Mexico City in March 2006, at a ground-based station near Mexico City (the T1 supersite) and from the NSF/NCAR C-130 aircraft. At the surface, measurements are typically smaller by up to 25 % in the morning, 10% at noon, and 40% in the afternoon, than actinic flux modeled for clean, cloud-free conditions. When measurements of PBL height, NO2 concentration and aerosols optical properties are included in the model, the agreement improves to within ±10% in the morning and afternoon, and ±3% at noon. Based on daily averages, aerosols account for 68%, NO2 for 25%, and residual uncertainties for 7% of these AF reductions observed at the surface. Several overpasses from the C-130 aircraft provided the opportunity to examine the actinic flux perturbations aloft, and also show better agreement with the model when aerosol and NO2 effects are included above and below the flight altitude. TUV model simulations show that the vertical structure of the actinic flux is sensitive to the choice of the aerosol single scattering albedo (SSA) at UV wavelengths. Typically, aerosols caused enhanced AF above the PBL and reduced AF near the surface. However, for highly scattering aerosols (SSA > 0.95), enhancements can penetrate well into the PBL, while for strongly absorbing aerosols (SSA<0.7) reductions in AF are computed in the free troposphere as well as in the PBL. Additional measurements of the SSA at these wavelengths are needed to better constrain the effect of aerosols on the vertical structure of the actinic flux.

  6. SU-E-T-167: Evaluation of Mobius Dose Calculation Engine Using Out of the Box Preconfigured Beam Data

    SciTech Connect (OSTI)

    Cardan, R [UAB University of Alabama, Birmingham, Birmingham, AL (United States); Faught, A [MD Anderson Cancer Center, Houston, TX (United States); Huang, M; Benhabib, S [University of Alabama at Birmingham, Birmingham, AL (United States); Brezovich, I; Popple, R [University of Alabama Birmingham, Birmingham, AL (United States); Followill, D [UT MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Determine the dose calculation accuracy of a preconfigured Mobius server for use in secondary checks of a treatment planning system. Methods: 10 plans were created for irradiation on two of the IROC (formerly RPC) accreditation phantoms: 4 for the head and neck phantom and 6 for the lung phantom. The plans each were created using one of four different photon energies (6FFF, 10 FFF, 6X, and 15X) and were varied in treatment type including VMAT, step and shoot IMRT, dynamic MLC IMRT (DMLC), and conformal RT (CRT). The TLDs in the phantoms were contoured, and each plan was sent for calculation to Mobius software (Mobius Medical Systems, Houston, TX) with a default configuration. Each plan was then irradiated on the planned phantom 3 times to create an average reading across 56 TLDs. These readings were then compared against the corresponding Mobius calculation at each TLD location. Results: The mean difference (MD) normalized to the plan prescription dose between each TLD and Mobius calculation for all measurements was 0.5 ± 3.3%, with a maximum difference of 8.4%. The MD was 0.6 ± 3.8%, ? 2.0 ± 1.9%, 1.7 ± 3.7%, and 1.9 ± 1.2% across the 6FFF, 10FFF, 6X and 15X energies respectively. The MD was ?1.2 ± 2.3% for lung plans and 1.8 ± 3.5% for head/neck plans. Across treatment types, the MD ranged from ? 1.8 ± 1.7% for CRT to 4.3 ± 2.4 % for DMLC. Conclusion: Out of the box and preconfigured, Mobius provides accurate dose calculations with respect to beam energy, treatment type, and treatment site.

  7. Type A verification report for the high flux beam reactor stack and grounds, Brookhaven National Laboratory, Upton, New York

    SciTech Connect (OSTI)

    Harpenau, Evan M.

    2012-01-13T23:59:59.000Z

    The U.S. Department of Energy (DOE) Order 458.1 requires independent verification (IV) of DOE cleanup projects (DOE 2011). The Oak Ridge Institute for Science and Education (ORISE) has been designated as the responsible organization for IV of the High Flux Beam Reactor (HFBR) Stack and Grounds area at Brookhaven National Laboratory (BNL) in Upton, New York. The IV evaluation may consist of an in-process inspection with document and data reviews (Type A Verification) or a confirmatory survey of the site (Type B Verification). DOE and ORISE determined that a Type A verification of the documents and data for the HFBR Stack and Grounds: Survey Units (SU) 6, 7, and 8 was appropriate based on the initial survey unit classification, the walkover surveys, and the final analytical results provided by the Brookhaven Science Associates (BSA). The HFBR Stack and Grounds surveys began in June 2011 and were completed in September 2011. Survey activities by BSA included gamma walkover scans and sampling of the as-left soils in accordance with the BSA Work Procedure (BNL 2010a). The Field Sampling Plan - Stack and Remaining HFBR Outside Areas (FSP) stated that gamma walk-over surveys would be conducted with a bare sodium iodide (NaI) detector, and a collimated detector would be used to check areas with elevated count rates to locate the source of the high readings (BNL 2010b). BSA used the Mult- Agency Radiation Survey and Site Investigation Manual (MARSSIM) principles for determining the classifications of each survey unit. Therefore, SUs 6 and 7 were identified as Class 1 and SU 8 was deemed Class 2 (BNL 2010b). Gamma walkover surveys of SUs 6, 7, and 8 were completed using a 2?2 NaI detector coupled to a data-logger with a global positioning system (GPS). The 100% scan surveys conducted prior to the final status survey (FSS) sampling identified two general soil areas and two isolated soil locations with elevated radioactivity. The general areas of elevated activity identified were investigated further with a collimated NaI detector. The uncollimated average gamma count rate was less than 15,000 counts per minute (cpm) for the SU 6, 7, and 8 composite area (BNL 2011a). Elevated count rates were observed in portions of each survey unit. The general areas of elevated counts near the Building 801 ventilation and operations and the entry to the Stack were determined to be directly related to the radioactive processes in those structures. To compensate for this radioactive shine, a collimated or shielded detector was used to lower the background count rate (BNL 2011b and c). This allowed the surveyor(s) to distinguish between background and actual radioactive contamination. Collimated gamma survey count rates in these shine affected areas were below 9,000 cpm (BNL 2011a). The average background count rate of 7,500 cpm was reported by BSA for uncollimated NaI detectors (BNL 2011d). The average collimated background ranged from 4,500-6,500 cpm in the westernmost part of SU 8 and from 2,000-3,500 cpm in all other areas (BNL 2011e). Based on these data, no further investigations were necessary for these general areas. SU 8 was the only survey unit that exhibited verified elevated radioactivity levels. The first of two isolated locations of elevated radioactivity had an uncollimated direct measurement of 50,000 cpm with an area background of 7,500 cpm (BNL 2011f). The second small area exhibiting elevated radiation levels was identified at a depth of 6 inches from the surface. The maximum reported count rate of 28,000 cpm was observed during scanning (BNL 2011g). The affected areas were remediated, and the contaminated soils were placed in an intermodal container for disposal. BSA's post-remediation walkover surveys were expanded to include a 10-foot radius around the excavated locations, and it was determined that further investigation was not required for these areas (BNL 2011 f and g). The post-remediation soil samples were collected and analyzed with onsite gamma spectroscopy equipment. These samples were also included with the FSS s

  8. TYPE A VERIFICATION REPORT FOR THE HIGH FLUX BEAM REACTOR STACK AND GROUNDS, BROOKHAVEN NATIONAL LABORATORY, UPTON, NEW YORK DCN 5098-SR-08-0

    SciTech Connect (OSTI)

    Evan Harpenau

    2011-11-30T23:59:59.000Z

    The U.S. Department of Energy (DOE) Order 458.1 requires independent verification (IV) of DOE cleanup projects (DOE 2011). The Oak Ridge Institute for Science and Education (ORISE) has been designated as the responsible organization for IV of the High Flux Beam Reactor (HFBR) Stack and Grounds area at Brookhaven National Laboratory (BNL) in Upton, New York. The IV evaluation may consist of an in-process inspection with document and data reviews (Type A Verification) or a confirmatory survey of the site (Type B Verification). DOE and ORISE determined that a Type A verification of the documents and data for the HFBR Stack and Grounds: Survey Units (SU) 6, 7, and 8 was appropriate based on the initial survey unit classification, the walkover surveys, and the final analytical results provided by the Brookhaven Science Associates (BSA).

  9. Design and characterization of 2.45 GHz electron cyclotron resonance plasma source with magnetron magnetic field configuration for high flux of hyperthermal neutral beam

    SciTech Connect (OSTI)

    Kim, Seong Bong [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Kim, Dae Chul; Yoo, Suk Jae [Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Namkung, Won; Cho, Moohyun [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of)

    2010-08-15T23:59:59.000Z

    A 2.45 GHz electron cyclotron resonance (ECR) source with a magnetron magnetic field configuration was developed to meet the demand of a hyperthermal neutral beam (HNB) flux on a substrate of more than 1x10{sup 15} cm{sup -2} s{sup -1} for industrial applications. The parameters of the operating pressure, ion density, electron temperature, and distance between the neutralization plate and the substrate for the HNB source are specified in a theoretical analysis. The electron temperature and the ion density are measured to characterize the ECR HNB source using a Langmuir probe and optical emission spectroscopy. The parameters of the ECR HNB source are in good agreement with the theoretically specified parameters.

  10. Calculation and Verification of a Planar Pencil Beam Kernel Through the Hankel Transform of Measured OARs for a Radiosurgery System with Cones

    SciTech Connect (OSTI)

    Vargas Verdesoto, Milton X. [Centro Oncologico de Chihuahua, Hacienda de la Esperanza 6304, Chihuahua, Chihuahua (Mexico); Alvarez Romero, Jose T. [SSDL, Departamento de Metrologia de Radiaciones Ionizantes, Instituto Nacional de Investigaciones Nucleares, La Marquesa, Ocoyoacac, Estado de Mexico 52750 (Mexico)

    2010-12-07T23:59:59.000Z

    A planar multienergetic pencil beam kernel with rotational symmetry is calculated for a stereotactic radiosurgery system, SRS, BrainLAB with cones, employing the deconvolution method of the off axis ratio profile, OAR, corresponding to the cone of 35 mm in diameter for a 6 MV photon beam produced by a linear accelerator Varian 2100 C/D. Before the deconvolution, the experimental OAR is corrected for beam divergence and variations of the spectral fluence {Phi}, using a boundary function BF. The function BF and the fluence {Phi} are transformed to the conjugate space with the zero order Hankel function, which is the appropriate transform due to the radial symmetry of the circular beams generated by the cones. The kernel in the conjugate space is obtained as the ratio of the transform of BF to the transform of {Phi}, therefore the kernel in the real space is calculated as the inverse transform of the kernel in the conjugate space. To validate the kernel in the real space, it is convolved with the fluence of the cones of 7.5, 12.5, 15, 17.5, 20, 22.5, 25, 30 and 35 mm in diameter. The comparison of the OARs calculated and measured shows a maximum difference of 4.5% in the zones of high gradient of dose, and a difference less than 2% in the regions of low gradient of dose. Finally, the expanded uncertainty of the kernel is estimated and reported.

  11. Atmospheric Neutrino Fluxes

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2005-02-18T23:59:59.000Z

    Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.

  12. Quantitative assessment of the accuracy of dose calculation using pencil beam and Monte Carlo algorithms and requirements for clinical quality assurance

    SciTech Connect (OSTI)

    Ali, Imad, E-mail: iali@ouhsc.edu [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Ahmad, Salahuddin [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2013-10-01T23:59:59.000Z

    To compare the doses calculated using the BrainLAB pencil beam (PB) and Monte Carlo (MC) algorithms for tumors located in various sites including the lung and evaluate quality assurance procedures required for the verification of the accuracy of dose calculation. The dose-calculation accuracy of PB and MC was also assessed quantitatively with measurement using ionization chamber and Gafchromic films placed in solid water and heterogeneous phantoms. The dose was calculated using PB convolution and MC algorithms in the iPlan treatment planning system from BrainLAB. The dose calculation was performed on the patient's computed tomography images with lesions in various treatment sites including 5 lungs, 5 prostates, 4 brains, 2 head and necks, and 2 paraspinal tissues. A combination of conventional, conformal, and intensity-modulated radiation therapy plans was used in dose calculation. The leaf sequence from intensity-modulated radiation therapy plans or beam shapes from conformal plans and monitor units and other planning parameters calculated by the PB were identical for calculating dose with MC. Heterogeneity correction was considered in both PB and MC dose calculations. Dose-volume parameters such as V95 (volume covered by 95% of prescription dose), dose distributions, and gamma analysis were used to evaluate the calculated dose by PB and MC. The measured doses by ionization chamber and EBT GAFCHROMIC film in solid water and heterogeneous phantoms were used to quantitatively asses the accuracy of dose calculated by PB and MC. The dose-volume histograms and dose distributions calculated by PB and MC in the brain, prostate, paraspinal, and head and neck were in good agreement with one another (within 5%) and provided acceptable planning target volume coverage. However, dose distributions of the patients with lung cancer had large discrepancies. For a plan optimized with PB, the dose coverage was shown as clinically acceptable, whereas in reality, the MC showed a systematic lack of dose coverage. The dose calculated by PB for lung tumors was overestimated by up to 40%. An interesting feature that was observed is that despite large discrepancies in dose-volume histogram coverage of the planning target volume between PB and MC, the point doses at the isocenter (center of the lesions) calculated by both algorithms were within 7% even for lung cases. The dose distributions measured with EBT GAFCHROMIC films in heterogeneous phantoms showed large discrepancies of nearly 15% lower than PB at interfaces between heterogeneous media, where these lower doses measured by the film were in agreement with those by MC. The doses (V95) calculated by MC and PB agreed within 5% for treatment sites with small tissue heterogeneities such as the prostate, brain, head and neck, and paraspinal tumors. Considerable discrepancies, up to 40%, were observed in the dose-volume coverage between MC and PB in lung tumors, which may affect clinical outcomes. The discrepancies between MC and PB increased for 15 MV compared with 6 MV indicating the importance of implementation of accurate clinical treatment planning such as MC. The comparison of point doses is not representative of the discrepancies in dose coverage and might be misleading in evaluating the accuracy of dose calculation between PB and MC. Thus, the clinical quality assurance procedures required to verify the accuracy of dose calculation using PB and MC need to consider measurements of 2- and 3-dimensional dose distributions rather than a single point measurement using heterogeneous phantoms instead of homogenous water-equivalent phantoms.

  13. Optimal beam pattern to maximize inclusion residence time in an electron beam melting hearth

    SciTech Connect (OSTI)

    Powell, A.; Pal, U. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Avyle, J. van den [Sandia National Labs., Albuquerque, NM (United States)

    1997-02-01T23:59:59.000Z

    Approximate probabilities of inclusion survival through an electron beam melting hearth are computed from nitride dissolution rates, flotation velocities, and residence times. Dissolution rates were determined by measuring shrinkage rates of pure TiN and nitrided sponge in small pools of molten titanium in an electron beam melting hearth. Flotation velocities were calculated using correlations for fluid flow around spheres, and show that particles sink or float unless their densities are extremely close to that of molten titanium. Flow field characteristics which lead to effective inclusion removal are discussed in terms of heat flux pattern required to produce them, based on the electron beam`s unique ability to impart a nearly arbitrary heat flux pattern to the melt surface.

  14. Verification of TG-61 dose for synchrotron-produced monochromatic x-ray beams using fluence-normalized MCNP5 calculations

    SciTech Connect (OSTI)

    Brown, Thomas A. D.; Hogstrom, Kenneth R.; Alvarez, Diane; Matthews, Kenneth L. II; Ham, Kyungmin [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 and Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Center for Advanced Microstructures and Devices, Louisiana State University and A and M College, 6980 Jefferson Highway, Baton Rouge, Louisiana 70806 (United States)

    2012-12-15T23:59:59.000Z

    Purpose: Ion chamber dosimetry is being used to calibrate dose for cell irradiations designed to investigate photoactivated Auger electron therapy at the Louisiana State University Center for Advanced Microstructures and Devices (CAMD) synchrotron facility. This study performed a dosimetry intercomparison for synchrotron-produced monochromatic x-ray beams at 25 and 35 keV. Ion chamber depth-dose measurements in a polymethylmethacrylate (PMMA) phantom were compared with the product of MCNP5 Monte Carlo calculations of dose per fluence and measured incident fluence. Methods: Monochromatic beams of 25 and 35 keV were generated on the tomography beamline at CAMD. A cylindrical, air-equivalent ion chamber was used to measure the ionization created in a 10 Multiplication-Sign 10 Multiplication-Sign 10-cm{sup 3} PMMA phantom for depths from 0.6 to 7.7 cm. The American Association of Physicists in Medicine TG-61 protocol was applied to convert measured ionization into dose. Photon fluence was determined using a NaI detector to make scattering measurements of the beam from a thin polyethylene target at angles 30 Degree-Sign -60 Degree-Sign . Differential Compton and Rayleigh scattering cross sections obtained from xraylib, an ANSI C library for x-ray-matter interactions, were applied to derive the incident fluence. MCNP5 simulations of the irradiation geometry provided the dose deposition per photon fluence as a function of depth in the phantom. Results: At 25 keV the fluence-normalized MCNP5 dose overestimated the ion-chamber measured dose by an average of 7.2 {+-} 3.0%-2.1 {+-} 3.0% for PMMA depths from 0.6 to 7.7 cm, respectively. At 35 keV the fluence-normalized MCNP5 dose underestimated the ion-chamber measured dose by an average of 1.0 {+-} 3.4%-2.5 {+-} 3.4%, respectively. Conclusions: These results showed that TG-61 ion chamber dosimetry, used to calibrate dose output for cell irradiations, agreed with fluence-normalized MCNP5 calculations to within approximately 7% and 3% at 25 and 35 keV, respectively.

  15. Atmospheric neutrino flux at INO site

    SciTech Connect (OSTI)

    Honda, Morihiro [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan)

    2011-11-23T23:59:59.000Z

    To illustrate the calculation of the atmospheric neutrino flux, we briefly explain our calculation scheme and important components, such as primary cosmic ray spectra, interaction model, and geomagnetic model. Then, we calculate the atmospheric neutrino flux at INO site in our calculation scheme. We compare the calculated atmospheric neutrino fluxes predicted at INO with those at other major neutrino detector sites, especially that at SK site.

  16. Determining Reactor Neutrino Flux

    E-Print Network [OSTI]

    Jun Cao

    2012-03-08T23:59:59.000Z

    Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

  17. Beam geometry selection using sequential beam addition

    SciTech Connect (OSTI)

    Popple, Richard A., E-mail: rpopple@uabmc.edu; Brezovich, Ivan A.; Fiveash, John B. [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)] [Department of Radiation Oncology, The University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, Alabama 35294 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: The selection of optimal beam geometry has been of interest since the inception of conformal radiotherapy. The authors report on sequential beam addition, a simple beam geometry selection method, for intensity modulated radiation therapy. Methods: The sequential beam addition algorithm (SBA) requires definition of an objective function (score) and a set of candidate beam geometries (pool). In the first iteration, the optimal score is determined for each beam in the pool and the beam with the best score selected. In the next iteration, the optimal score is calculated for each beam remaining in the pool combined with the beam selected in the first iteration, and the best scoring beam is selected. The process is repeated until the desired number of beams is reached. The authors selected three treatment sites, breast, lung, and brain, and determined beam arrangements for up to 11 beams from a pool comprised of 25 equiangular transverse beams. For the brain, arrangements were additionally selected from a pool of 22 noncoplanar beams. Scores were determined for geometries comprised equiangular transverse beams (EQA), as well as two tangential beams for the breast case. Results: In all cases, SBA resulted in scores superior to EQA. The breast case had the strongest dependence on beam geometry, for which only the 7-beam EQA geometry had a score better than the two tangential beams, whereas all SBA geometries with more than two beams were superior. In the lung case, EQA and SBA scores monotonically improved with increasing number of beams; however, SBA required fewer beams to achieve scores equivalent to EQA. For the brain case, SBA with a coplanar pool was equivalent to EQA, while the noncoplanar pool resulted in slightly better scores; however, the dose-volume histograms demonstrated that the differences were not clinically significant. Conclusions: For situations in which beam geometry has a significant effect on the objective function, SBA can identify arrangements equivalent to equiangular geometries but using fewer beams. Furthermore, SBA provides the value of the objective function as the number of beams is increased, allowing the planner to select the minimal beam number that achieves the clinical goals. The method is simple to implement and could readily be incorporated into an existing optimization system.

  18. High Heat Flux Components Program

    SciTech Connect (OSTI)

    Whitley, J.B.

    1983-01-01T23:59:59.000Z

    Purpose is the development of the technologies necessary to design, build and operate high heat flux components such as actively cooled limiters, divertor collector plates, R.F. antennas, mirror end cells, mirror halo collectors, direct convertor collectors, and neutral beam dumps. These components require an integrated design that considers the plasma-materials interaction (PMI) issues, heat removal problems and materials issues (including possible low Z coatings and claddings). As a general definition, high heat flux components see heat fluxes ranging from 1 to 100 MW/m/sup 2/. Suitable materials include copper and copper alloys.

  19. Performance predictions for a laser intensified thermal beam for use in high resolution Focused Ion Beam instruments

    E-Print Network [OSTI]

    Wouters, S H W; Notermans, R P M J W; Debernardi, N; Mutsaers, P H A; Luiten, O J; Vredenbregt, E J D

    2014-01-01T23:59:59.000Z

    Photo-ionization of a laser-cooled and compressed atomic beam from a high-flux thermal source can be used to create a high-brightness ion beam for use in Focus Ion Beam (FIB) instruments. Here we show using calculations and Doppler cooling simulations that an atomic rubidium beam with a brightness of $2.1 \\times 10^7 A/(m^2\\,sr\\,eV)$ at a current of 1 nA can be created using a compact 5 cm long 2D magneto-optical compressor which is more than an order of magnitude better than the current state of the art Liquid Metal Ion Source.

  20. Calculational analysis of structural activation induced by 20-100 MeV proton beam loss in high-power linear accelerators 

    E-Print Network [OSTI]

    Lee, Stacey Kirsten

    1994-01-01T23:59:59.000Z

    to obtain dose rate estimates at several locations near the accelerator. To perform these calculations, simplified computer models were developed from detailed engineering drawings of a typical high-power accelerator design. This research focused on the 20...

  1. Temperture and composition dependence of the high flux plasma sputtering yield of Cu-Li binary alloys

    SciTech Connect (OSTI)

    Krauss, A.R.; Mendelsohn, M.H.; Gruen, D.M.; Conn, R.W.; Goebel, D.M.; Hirooka, Y.; Leung, W.K.; Bohdansky, J.

    1986-01-01T23:59:59.000Z

    High flux deuterium plasma sputtering and ion beam experiments have been performed on Cu-Li alloys to determine if the reduction in copper erosion previously predicted and observed in low flux ion beam experiments occurs at particle fluxes representative of an RFP first wall or tokamak limiter. Partial sputtering yields of the copper and lithium components have been measured as a function of alloy composition and sample temperature using optical plasma emission spectroscopy, weight loss and catcher foil techniques. It is found that the lithium sputtering yield increases with increasing sample temperature while the copper yield decreases by as much as two orders of magnitude. The temperature required to obtain the reduction in copper erosion is found to be a function of bulk lithium concentration. Consequences of these experimental results for anticipated erosion/redeposition properties are calculated, and the Cu-Li alloy in found to compare favorably with conventional low-Z materials.

  2. BEAMS3D Neutral Beam Injection Model

    SciTech Connect (OSTI)

    Lazerson, Samuel

    2014-04-14T23:59:59.000Z

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  3. Calculator Policy

    E-Print Network [OSTI]

    charlotb

    2014-08-24T23:59:59.000Z

    MA 16010 -- CALCULATOR POLICY. A ONE-LINE scientific calculator is REQUIRED. No other calculator is allowed. RECOMMENDED: TI-30Xa calculator

  4. Near beam-gas background for LHCb at 3.5 TeV

    E-Print Network [OSTI]

    Brett, D R; Corti, G; Alessio, F; Jacobsson, R; Talanov, V; Lieng, M H

    2011-01-01T23:59:59.000Z

    We consider the machine induced backgrounds for LHCb arising from collisions of the beam with residual gas in the long straight sections of the LHC close to the experiment. We concentrate on the background particle fluxes initiated by inelastic beam-gas interactions with a direct line of sight to the experiment, with the potential impact on the experiment increasing for larger beam currents and changing gas pressures. In this paper we calculate the background rates for parameters foreseen with LHC running in 2011, using realistic residual pressure profiles. We also discuss the effect of using a pressure profile formulated in terms of equivalent hydrogen, through weighting of other residual gases by their cross section, upon the radial fluxes from the machine and the detector response. We present the expected rates and the error introduced through this approximation.

  5. Calculator Policy

    E-Print Network [OSTI]

    charlotb

    2014-06-10T23:59:59.000Z

    MA 15800 – Calculators – GOOD AND BAD. ONLY ONE-LINE scientific calculators are permitted. *RECOMMENDED CALCULATOR: TI-30XA(See Below).

  6. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, John B. (Lansing, NY)

    1997-01-01T23:59:59.000Z

    An improved pulsed ion beam source having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center.

  7. Characterization of Dosimetry of the BMRR Horizontal Thimble Tubes and Broad Beam Facility.

    SciTech Connect (OSTI)

    Hu,J.P.; Reciniello, R.N.; Holden, N.E.

    2008-05-05T23:59:59.000Z

    The Brookhaven Medical Research Reactor was a 5 mega-watt, light-water cooled and heavy-graphite moderated research facility. It has two shutter-equipped treatment rooms, three horizontally extended thimble tubes, and an ex-core broad beam facility. The three experimental thimbles, or activation ports, external to the reactor tank were designed for several uses, including the investigations on diagnostic and therapeutic methods using radioactive isotopes of very short half-life, the analysis of radiation exposure on tissue-equivalent materials using a collimated neutron beam, and the evaluation of dose effects on biological cells to improve medical treatment. At the broad beam facility where the distribution of thermal neutrons was essential uniform, a wide variety of mammalian whole-body exposures were studied using animals such as burros or mice. Also studied at the broad beam were whole-body phantom experiments, involving the use of a neutron or photon beam streaming through a screen to obtain the flux spectrum suitable for dose analysis on the sugar-urea-water mixture, a tissue-equivalent material. Calculations of the flux and the dose at beam ports based on Monte Carlo particle-transport code were performed, and measurements conducted at the same tally locations were made using bare or cadmium-covered gold foils. Analytical results, which show good agreement with measurement data, are presented in the paper.

  8. Fast flux locked loop

    DOE Patents [OSTI]

    Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Independence, MO)

    2002-09-10T23:59:59.000Z

    A flux locked loop for providing an electrical feedback signal, the flux locked loop employing radio-frequency components and technology to extend the flux modulation frequency and tracking loop bandwidth. The flux locked loop of the present invention has particularly useful application in read-out electronics for DC SQUID magnetic measurement systems, in which case the electrical signal output by the flux locked loop represents an unknown magnetic flux applied to the DC SQUID.

  9. Calculator Policy

    E-Print Network [OSTI]

    charlotb

    2014-08-15T23:59:59.000Z

    MA 15300 Calculator Policy. ONLY a TI-30Xa scientific calculator is allowed on quizzes and exams. If you have questions, please email the course coordinator ...

  10. Calculator Policy

    E-Print Network [OSTI]

    charlotb

    2014-12-17T23:59:59.000Z

    MA 15910 Calculator Policy. ONLY a TI-30Xa scientific calculator is allowed on quizzes and exams. If you have questions, please email the course coordinator ...

  11. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Kirkby, Jasper

    2001-01-01T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual e...

  12. Photon beam position monitor

    DOE Patents [OSTI]

    Kuzay, T.M.; Shu, D.

    1995-02-07T23:59:59.000Z

    A photon beam position monitor is disclosed for use in the front end of a beamline of a high heat flux and high energy photon source such as a synchrotron radiation storage ring detects and measures the position and, when a pair of such monitors are used in tandem, the slope of a photon beam emanating from an insertion device such as a wiggler or an undulator inserted in the straight sections of the ring. The photon beam position monitor includes a plurality of spaced blades for precisely locating the photon beam, with each blade comprised of chemical vapor deposition (CVD) diamond with an outer metal coating of a photon sensitive metal such as tungsten, molybdenum, etc., which combination emits electrons when a high energy photon beam is incident upon the blade. Two such monitors are contemplated for use in the front end of the beamline, with the two monitors having vertically and horizontally offset detector blades to avoid blade ''shadowing''. Provision is made for aligning the detector blades with the photon beam and limiting detector blade temperature during operation. 18 figs.

  13. Recent advances of strong-strong beam-beam simulation

    SciTech Connect (OSTI)

    Qiang, Ji; Furman, Miguel A.; Ryne, Robert D.; Fischer, Wolfram; Ohmi,Kazuhito

    2004-09-15T23:59:59.000Z

    In this paper, we report on recent advances in strong-strong beam-beam simulation. Numerical methods used in the calculation of the beam-beam forces are reviewed. A new computational method to solve the Poisson equation on nonuniform grid is presented. This method reduces the computational cost by a half compared with the standard FFT based method on uniform grid. It is also more accurate than the standard method for a colliding beam with low transverse aspect ratio. In applications, we present the study of coherent modes with multi-bunch, multi-collision beam-beam interactions at RHIC. We also present the strong-strong simulation of the luminosity evolution at KEKB with and without finite crossing angle.

  14. Beam characterization by wavefront sensor

    DOE Patents [OSTI]

    Neal, D.R.; Alford, W.J.; Gruetzner, J.K.

    1999-08-10T23:59:59.000Z

    An apparatus and method are disclosed for characterizing an energy beam (such as a laser) with a two-dimensional wavefront sensor, such as a Shack-Hartmann lenslet array. The sensor measures wavefront slope and irradiance of the beam at a single point on the beam and calculates a space-beamwidth product. A detector array such as a charge coupled device camera is preferably employed. 21 figs.

  15. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    designs (relatively) Photovoltaic Solar P a n e l AtmosphereCALIFORNIA, SAN DIEGO Photovoltaic Roof Heat Flux A ThesisABSTRACT OF T H E THESIS Photovoltaic Roof Heat Flux by

  16. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Jasper Kirkby

    2001-04-27T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual effect on global temperatures of the burning of fossil fuels, an issue of profound importance to society. Furthermore, light radio-isotope records indicate a correlation has existed between global climate and the cosmic ray flux extending back over the present inter-glacial and perhaps earlier. This suggests it may eventually become possible to make long-term (10-1,000 year) predictions of changes in the Earth's climate, provided a deeper understanding can be achieved of the ``geomagnetic climate'' of the Sun and Earth that modulates the cosmic-ray flux.

  17. Luminosity and beam-beam

    E-Print Network [OSTI]

    Papotti, G; Trad, G

    We report on observations on luminosity evolution and beam-beam interaction from the 2011 physics run. Extrapolations for 2012 are attempted and a list of desired studies and machine developments is included.

  18. High Gradient Two-Beam Electron Accelerator

    SciTech Connect (OSTI)

    Jiang, Y. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Kazakov, S. Yu. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Kuzikov, S. V. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Institute of Applied Physics, Nizhny Novgorod, 603600 (Russian Federation); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States)

    2010-11-04T23:59:59.000Z

    A high-gradient two-beam electron accelerator structure using detuned cavities is described. A self-consistent theory based on a circuit model is presented to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam. Experimental efforts are being carried out to demonstrate this acceleration concept.

  19. Distribution of electric field and energy flux around the cracks on the surfaces of Nd-doped phosphate glasses

    SciTech Connect (OSTI)

    Zhang Lei; Huang Li; Fan Sijun; Bai Gongxun; Li Kefeng; Chen Wei; Hu Lili

    2010-12-10T23:59:59.000Z

    We simulate and calculate numerically the electromagnetic field and energy flux around a surface crack of an Nd-doped phosphate laser glass by using the finite-difference time-domain method. Because of a strong interference between the incident wave and the total internal reflections from the crack and the glass surface, the electric field is redistributed and enhanced. The results show that the electric-field distribution and corresponding energy flux component depend sensitively on the light polarization and crack geometry, such as orientation and depth. The polarization of the incident laser beam relative to the crack surfaces will determine the profile of the electric field around the crack. Under TE wave incidence, the energy flux peak is always inside the glass. But under TM wave incidence, the energy flux peak will be located inside the glass or inside the air gap. For both incident modes, the light intensification factor increases with the crack depth, especially for energy flux along the surface. Because cracks on the polished surfaces are the same as the roots extending down, the probability for much larger intensification occurring is high. The results suggest that the surface laser-damage threshold of Nd-doped phosphate may decrease dramatically with subsurface damage.

  20. Optical remote diagnostics of atmospheric propagating beams of ionizing radiation

    DOE Patents [OSTI]

    Karl, Jr., Robert R. (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    Data is obtained for use in diagnosing the characteristics of a beam of ionizing radiation, such as charged particle beams, neutral particle beams, and gamma ray beams. In one embodiment the beam is emitted through the atmosphere and produces nitrogen fluorescence during passage through air. The nitrogen fluorescence is detected along the beam path to provide an intensity from which various beam characteristics can be calculated from known tabulations. Optical detecting equipment is preferably located orthogonal to the beam path at a distance effective to include the entire beam path in the equipment field of view.

  1. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, J.B.

    1997-08-12T23:59:59.000Z

    An improved pulsed ion beam source is disclosed having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center. 12 figs.

  2. Neutral beam dump with cathodic arc titanium gettering

    SciTech Connect (OSTI)

    Smirnov, A.; Korepanov, S. A.; Putvinski, S. [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States); Krivenko, A. S.; Murakhtin, S. V.; Savkin, V. Ya. [Budker Institute of Nuclear Physics, Novosibirsk 630090 (Russian Federation)

    2011-03-15T23:59:59.000Z

    An incomplete neutral beam capture can degrade the plasma performance in neutral beam driven plasma machines. The beam dumps mitigating the shine-through beam recycling must entrap and retain large particle loads while maintaining the beam-exposed surfaces clean of the residual impurities. The cathodic arc gettering, which provides high evaporation rate coupled with a fast time response, is a powerful and versatile technique for depositing clean getter films in vacuum. A compact neutral beam dump utilizing the titanium arc gettering was developed for a field-reversed configuration plasma sustained by 1 MW, 20-40 keV neutral hydrogen beams. The titanium evaporator features a new improved design. The beam dump is capable of handling large pulsed gas loads, has a high sorption capacity, and is robust and reliable. With the beam particle flux density of 5 x 10{sup 17} H/(cm{sup 2}s) sustained for 3-10 ms, the beam recycling coefficient, defined as twice the ratio of the hydrogen molecular flux leaving the beam dump to the incident flux of high-energy neutral atoms, is {approx}0.7. The use of the beam dump allows us to significantly reduce the recycling of the shine-through neutral beam as well as to improve the vacuum conditions in the machine.

  3. PHELIX for flux compression studies

    SciTech Connect (OSTI)

    Turchi, Peter J [Los Alamos National Laboratory; Rousculp, Christopher L [Los Alamos National Laboratory; Reinovsky, Robert E [Los Alamos National Laboratory; Reass, William A [Los Alamos National Laboratory; Griego, Jeffrey R [Los Alamos National Laboratory; Oro, David M [Los Alamos National Laboratory; Merrill, Frank E [Los Alamos National Laboratory

    2010-06-28T23:59:59.000Z

    PHELIX (Precision High Energy-density Liner Implosion eXperiment) is a concept for studying electromagnetic implosions using proton radiography. This approach requires a portable pulsed power and liner implosion apparatus that can be operated in conjunction with an 800 MeV proton beam at the Los Alamos Neutron Science Center. The high resolution (< 100 micron) provided by proton radiography combined with similar precision of liner implosions driven electromagnetically can permit close comparisons of multi-frame experimental data and numerical simulations within a single dynamic event. To achieve a portable implosion system for use at high energy-density in a proton laboratory area requires sub-megajoule energies applied to implosions only a few cms in radial and axial dimension. The associated inductance changes are therefore relatively modest, so a current step-up transformer arrangement is employed to avoid excessive loss to parasitic inductances that are relatively large for low-energy banks comprising only several capacitors and switches. We describe the design, construction and operation of the PHELIX system and discuss application to liner-driven, magnetic flux compression experiments. For the latter, the ability of strong magnetic fields to deflect the proton beam may offer a novel technique for measurement of field distributions near perturbed surfaces.

  4. Stability of Single Particle Motion with Head-On Beam-Beam Compensation in the RHIC

    SciTech Connect (OSTI)

    Luo,Y.; Fischer, W.; Abreu, N.

    2008-05-01T23:59:59.000Z

    To compensate the large tune shift and tune spread generated by the head-on beam-beam interactions in the polarized proton run in the Relativistic Heavy Ion Collider (RHIC), we proposed a low energy electron beam with a Gaussian transverse profiles to collide head-on with the proton beam. In this article, with a weak-strong beam-beam interaction model, we investigate the stability of single particle motion in the presence of head-on beam-beam compensation. Tune footprints, tune diffusion, Lyapunov exponents, and 10{sup 6} turn dynamic apertures are calculated and compared between the cases without and with beam-beam compensation. A tune scan is performed and the possibility of increasing the bunch intensity is studied. The cause of tune footprint foldings is discussed, and the tune diffusion and Lyapunov exponent analysis are compared.

  5. Measurements and model calculations of radiative fluxes for the Cabauw

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals from a NewCuneo Matthew1, 20121 H( 7radialMHD

  6. Synchrotron radiation damping, intrabeam scattering and beam-beam simulations for HE-LHC

    SciTech Connect (OSTI)

    Valishev, A.; /Fermilab

    2011-03-01T23:59:59.000Z

    The proposed High-Energy LHC project presents an unusual combination of strong synchrotron radiation damping and intrabeam scattering, which is not seen in present-day hadron colliders. The subject of investigation reported in this paper was the simulation of beam-beam effect for the HE-LHC parameters. Parameters of SR and IBS are calculated, and the luminosity evolution is simulated in the absence of beam-beam interaction. Then, a weak-strong numerical simulation is used to predict the effect of beam-beam interaction on particle losses and emittance evolution.

  7. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    e l Atmosphere ceiling, back panel roof, exposed roof insideSAN DIEGO Photovoltaic Roof Heat Flux A Thesis submitted i no n Convection Exposed Roof Temperature Seasonal Temperature

  8. Beams 92: Proceedings. Volume 2, Ion beams, electron beams, diagnostics

    SciTech Connect (OSTI)

    Mosher, D.; Cooperstein, G. [eds.] [Naval Research Lab., Washington, DC (United States)] [eds.; Naval Research Lab., Washington, DC (United States)

    1993-12-31T23:59:59.000Z

    This report contains papers on the following topics. Ion beam papers; electron beam papers; and these papers have been indexed separately elsewhere.

  9. absolute beam current: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (FBCCM) is an example. It is based on analogue signals from fast beam current transformers (FBCT) used nominally to measure the LHC bunch intensities. The FBCCM calculates...

  10. amp beam currents: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (FBCCM) is an example. It is based on analogue signals from fast beam current transformers (FBCT) used nominally to measure the LHC bunch intensities. The FBCCM calculates...

  11. Low energy beam line at the AGOR facility

    SciTech Connect (OSTI)

    Toprek, Dragan; Formanoy, Iwo; Brandenburg, Sytze [VINCA Institute of Nuclear Sciences, Laboratory for Nuclear and Plasma Physics, B.O. Box 522, 11001 Belgrade (Serbia and Montenegro); Kernfysisch Versneller Instituut (KVI), Zernikelaan 25, 9747 AA, Groningen (Netherlands)

    2005-01-01T23:59:59.000Z

    The origin of the low transmission through the low energy beam line between the electron cyclotron resonance source and the AGOR cyclotron has been investigated. Measurements of beam size and emittance, determined with the ''varying quadrupole method,'' are compared with calculations including fringe fields up to third order with the code COSY INFINITY. Calculations and measurements qualitatively agree; the calculations exhibit the large beam losses observed. On the basis of the calculations new settings have been determined, resulting in a significant increase of the transmission. To achieve full transmission a complete redesign of the beam line, in particular of the bending magnets, is needed.

  12. Investigation of edge neutral flux on the ISX-B tokamak using a low-energy charge-exchange analyzer

    SciTech Connect (OSTI)

    Thomas, D. M.

    1983-08-01T23:59:59.000Z

    To study the emission of D/sup 0/ from the periphery of a tokamak plasma, a low-energy neutral particle spectrometer optimized for (16 < E < 500 eV) has been built and employed on the Impurity Study Experiment (ISX-B) tokamak. The diagnostic utilizes a cesium vapor cell to form negative ions from the incident D/sup 0/ neutrals and a four-channel electrostatic analyzer to energy analyze the negative ions. The spectrometer was absolutely calibrated using D/sup 0/ beams formed by electron capture by positive ions in a gas cell and by photo-detachment of negative ions by a yttrium-aluminum-garnet laser. For the observation region chosen on ISX-B (120/sup 0/ toroidally away from the limiter, near the gas puff), the neutral particle flux has a two-component nature. These data are well fit by two separate exponential distributions of equivalent temperatures 6 to 8 eV for particle energies below about 80 eV and 70 to 80 eV for particle energies above 80 eV. For ohmically heated discharges, the measured particle flux in the energy range 25 to 700 eV is approx. 2.5 x 10/sup 15/ cm/sup -2/.s/sup -1/; the mean particle energy is approx. 70 eV, and the calculated flux at the wall is approx. 30 mW/cm/sup 2/. The major effect of neutral beam heating is to increase the particle flux in the 25- to 700-eV range by a factor of 3.

  13. Beam current controller for laser ion source

    DOE Patents [OSTI]

    Okamura, Masahiro

    2014-10-28T23:59:59.000Z

    The present invention relates to the design and use of an ion source with a rapid beam current controller for experimental and medicinal purposes. More particularly, the present invention relates to the design and use of a laser ion source with a magnetic field applied to confine a plasma flux caused by laser ablation.

  14. Characterization of X-ray generator beam profiles.

    SciTech Connect (OSTI)

    Mitchell, Dean J; Harding, Lee T.; Thoreson, Gregory G.; Theisen, Lisa Anne; Parmeter, John Ethan; Thompson, Kyle Richard

    2013-07-01T23:59:59.000Z

    T to compute the radiography properties of various materials, the flux profiles of X-ray sources must be characterized. This report describes the characterization of X-ray beam profiles from a Kimtron industrial 450 kVp radiography system with a Comet MXC-45 HP/11 bipolar oil-cooled X-ray tube. The empirical method described here uses a detector response function to derive photon flux profiles based on data collected with a small cadmium telluride detector. The flux profiles are then reduced to a simple parametric form that enables computation of beam profiles for arbitrary accelerator energies.

  15. ARM Energy Balance Bowen Ratio (EBBR) station: surf. heat flux and related data, 30-min

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Cook, David

    The Energy Balance Bowen Ratio (EBBR) system produces 30-min estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity. Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

  16. Radiative Flux Analysis

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Long, Chuck [NOAA

    The Radiative Flux Analysis is a technique for using surface broadband radiation measurements for detecting periods of clear (i.e. cloudless) skies, and using the detected clear-sky data to fit functions which are then used to produce continuous clear-sky estimates. The clear-sky estimates and measurements are then used in various ways to infer cloud macrophysical properties.

  17. Atmospheric State, Cloud Microphysics and Radiative Flux

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mace, Gerald

    Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.

  18. Accelerator beam profile analyzer

    DOE Patents [OSTI]

    Godel, Julius B. (Bayport, NY); Guillaume, Marcel (Grivegnee, BE); Lambrecht, Richard M. (East Quogue, NY); Withnell, Ronald (East Setauket, NY)

    1976-01-01T23:59:59.000Z

    A beam profile analyzer employing sector or quadrant plates each servo controlled to outline the edge of a beam.

  19. Beam Characterization at the Neutron Radiography Facility

    SciTech Connect (OSTI)

    Sarah Morgan; Jeffrey King

    2013-01-01T23:59:59.000Z

    The quality of a neutron imaging beam directly impacts the quality of radiographic images produced using that beam. Fully characterizing a neutron beam, including determination of the beam’s effective length-to-diameter ratio, neutron flux profile, energy spectrum, image quality, and beam divergence, is vital for producing quality radiographic images. This project characterized the east neutron imaging beamline at the Idaho National Laboratory Neutron Radiography Reactor (NRAD). The experiments which measured the beam’s effective length-to-diameter ratio and image quality are based on American Society for Testing and Materials (ASTM) standards. An analysis of the image produced by a calibrated phantom measured the beam divergence. The energy spectrum measurements consist of a series of foil irradiations using a selection of activation foils, compared to the results produced by a Monte Carlo n-Particle (MCNP) model of the beamline. Improvement of the existing NRAD MCNP beamline model includes validation of the model’s energy spectrum and the development of enhanced image simulation methods. The image simulation methods predict the radiographic image of an object based on the foil reaction rate data obtained by placing a model of the object in front of the image plane in an MCNP beamline model.

  20. MA 22400 -- CALCULATOR POLICY

    E-Print Network [OSTI]

    OwenDavis

    2014-08-22T23:59:59.000Z

    MA 22400 -- CALCULATOR POLICY. A ONE-LINE scientific calculator is REQUIRED. No other calculator is allowed. RECOMMENDED: TI-30Xa calculator

  1. Portable radiography system using a relativistic electron beam

    DOE Patents [OSTI]

    Hoeberling, R.F.

    1987-09-22T23:59:59.000Z

    A portable radiographic generator is provided with an explosive magnetic flux compression generator producing the high voltage necessary to generate a relativistic electron beam. The relativistic electron beam is provided with target materials which generates the desired radiographic pulse. The magnetic flux compression generator may require at least two conventional explosively driven generators in series to obtain a desired output voltage of at least 1 MV. The cathode and anode configuration of the diode are selected to provide a switching action wherein a high impedance load is presented to the magnetic flux compression generator when the high voltage is being generated, and thereafter switching to a low impedance load to generate the relativistic electron beam. Magnetic flux compression generators can be explosively driven and provided in a relatively compact, portable form for use with the relativistic x-ray equipment. 8 figs.

  2. Magnetic Flux Dynamics in Horizontally Cooled Superconducting Cavities

    E-Print Network [OSTI]

    Martinello, M; Grassellino, A; Crawford, A C; Melnychuk, O; Romanenko, A; Sergatkov, D A

    2015-01-01T23:59:59.000Z

    Previous studies on magnetic flux expulsion as a function of cooling details have been performed for superconducting niobium cavities with the cavity beam axis placed parallel respect to the helium cooling flow, and findings showed that for sufficient cooling thermogradients all magnetic flux could be expelled and very low residual resistance could be achieved. In this paper we investigate the flux trapping and its impact on radio frequency surface resistance when the resonators are positioned perpendicularly to the helium cooling flow, which is representative of how superconducting radio-frequency (SRF) cavities are cooled in an accelerator. We also extend the studies to different directions of applied magnetic field surrounding the resonator. Results show that in the cavity horizontal configuration there is a different impact of the various field components on the final surface resistance, and that several parameters have to be considered to understand flux dynamics. A newly discovered phenomenon of concent...

  3. Effect of Diffusion on Bunched Beam Echo

    SciTech Connect (OSTI)

    Stupakov, G.V.; Chao, A.W.; /SLAC

    2011-09-01T23:59:59.000Z

    When a beam receives a dipole kick, its centroid signal decoheres due to the betatron tune spread in the beam. Long after the signal has decohered, however, a followup quadrupole kick to the beam brings a pronounced echo back to the centroid signal. This echo effect has been analyzed for the case of a bunched beam in Ref. [1]. In this work, the perturbation calculation of Ref. [1] is extended to include a diffusion in betatron amplitude. The effect of diffusion on the magnitude of the echo is then parameterized and studied.

  4. Optical heat flux gauge

    DOE Patents [OSTI]

    Noel, B.W.; Borella, H.M.; Cates, M.R.; Turley, W.D.; MacArthur, C.D.; Cala, G.C.

    1991-04-09T23:59:59.000Z

    A heat flux gauge is disclosed comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable. 9 figures.

  5. Beam Status

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMForms About Batteries Batteries An error occurred. TryRing CurrentBeam

  6. Beam History

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplex historian ...BESFor Users LiveBattling birdBeam

  7. Beam History

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplex historian ...BESFor Users LiveBattlingBeam

  8. Estimates of the effect of a plasma momentum flux on the free surface of a thin film of liquid metal

    SciTech Connect (OSTI)

    Morley, N.B.; Gaizer, A.A.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)

    1994-12-31T23:59:59.000Z

    The idea of using a flowing thin film of liquid metal (LM) to protect the divertor surface of a tokamak from untimely erosion and radiation damage has gained some attention over the years but has met with criticism on several key issues. One such issue in particular is the effect the momentum flux of a very obliquely incident plasma particle stream on the shape of the free surface of LM. This momentum may push to LM to one side of the duct and cause the formation of dry spots no longer protected from the plasma beam. It is this issue that this paper addresses in the air of a first approximation. Estimates are made of the magnitude and direction of the flux of plasma momentum at the LM divertor surface. The effect of this flux is modeled with a modified version of the ordinary fluid dynamics code RIPPLE, designed for transient free surface fluid flow problems in which surface tension plays an important role. Initial results indicate that in the OHD approximation, ITER-like magnitudes of the momentum flux are comparable to the hydrostatic pressure of a thin LM film. The momentum can have a significant effect on the form of the free surface, causing both significant splashing as well as shifting of the LM to one side of the channel. Due to the inertial nature of this problem, movement of the metal cannot occur instantaneously and a maximum exposure time of the LM to the plasma, as a function of momentum flux magnitude and direction, is defined and estimated from the results of RIPPLE predictions. Full MHD calculations, while beyond the scope of this initial assessment, will be required to more fully and accurately characterize this effect.

  9. Divertor Heat Flux Mitigation in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D A; Menard, J E; Paul, S F; Raman, R; Roquemore, A L; Bell, M G; Bell, R E; Boedo, J A; Bush, C E; Kaita, R; Kugel, H W; LeBlanc, B P; Mueller, D

    2008-08-04T23:59:59.000Z

    Steady-state handling of divertor heat flux is a critical issue for both ITER and spherical torus-based devices with compact high power density divertors. Significant reduction of heat flux to the divertor plate has been achieved simultaneously with favorable core and pedestal confinement and stability properties in a highly-shaped lower single null configuration in the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 2000] using high magnetic flux expansion at the divertor strike point and the radiative divertor technique. A partial detachment of the outer strike point was achieved with divertor deuterium injection leading to peak flux reduction from 4-6 MW m{sup -2} to 0.5-2 MW m{sup -2} in small-ELM 0.8-1.0 MA, 4-6 MW neutral beam injection-heated H-mode discharges. A self-consistent picture of outer strike point partial detachment was evident from divertor heat flux profiles and recombination, particle flux and neutral pressure measurements. Analytic scrape-off layer parallel transport models were used for interpretation of NSTX detachment experiments. The modeling showed that the observed peak heat flux reduction and detachment are possible with high radiated power and momentum loss fractions, achievable with divertor gas injection, and nearly impossible to achieve with main electron density, divertor neutral density or recombination increases alone.

  10. Protostellar Accretion Flows Destabilized by Magnetic Flux Redistribution

    E-Print Network [OSTI]

    Krasnopolsky, Ruben; Shang, Hsien; Zhao, Bo

    2012-01-01T23:59:59.000Z

    Magnetic flux redistribution lies at the heart of the problem of star formation in dense cores of molecular clouds that are magnetized to a realistic level. If all of the magnetic flux of a typical core were to be dragged into the central star, the stellar field strength would be orders of magnitude higher than the observed values. This well-known "magnetic flux problem" can in principle be resolved through non-ideal MHD effects. Two dimensional (axisymmetric) calculations have shown that ambipolar diffusion, in particular, can transport magnetic flux outward relative to matter, allowing material to enter the central object without dragging the field lines along. We show through simulations that such axisymmetric protostellar accretion flows are unstable in three dimensions to magnetic interchange instability in the azimuthal direction. The instability is driven by the magnetic flux redistributed from the matter that enters the central object. It typically starts to develop during the transition from the pres...

  11. Stabilization of moduli by fluxes

    SciTech Connect (OSTI)

    Behrndt, Klaus [Albert-Einstein-Institute, Am Muehlenberg 1, 14476 Golm (Germany)

    2004-12-10T23:59:59.000Z

    In order to fix the moduli, non-trivial fluxes might the essential input. We summarize different aspects of compactifications in the presence of fluxes, as there is the relation to generalized Scherk-Schwarz reductions and gauged supergravity but also the description of flux-deformed geometries in terms of G-structures and intrinsic torsion.

  12. Method of automatic measurement and focus of an electron beam and apparatus therefore

    DOE Patents [OSTI]

    Giedt, W.H.; Campiotti, R.

    1996-01-09T23:59:59.000Z

    An electron beam focusing system, including a plural slit-type Faraday beam trap, for measuring the diameter of an electron beam and automatically focusing the beam for welding is disclosed. Beam size is determined from profiles of the current measured as the beam is swept over at least two narrow slits of the beam trap. An automated procedure changes the focus coil current until the focal point location is just below a workpiece surface. A parabolic equation is fitted to the calculated beam sizes from which optimal focus coil current and optimal beam diameter are determined. 12 figs.

  13. Solar wind driven plasma fluxes from the Venus ionosphere

    E-Print Network [OSTI]

    Perez-de-Tejada, H; Barabash, S; Zhang, T L; Sauvaud, J A; Durand-Manterola, H J; Reyes-Ruiz, M

    2012-01-01T23:59:59.000Z

    Measurements conducted with the ASPERA-4 instrument and the magnetometer of the Venus Express spacecraft show that the dynamic pressure of planetary O+ ion fluxes measured in the Venus wake can be significantly larger than the local magnetic pressure and, as a result, those ions are not being driven by magnetic forces but by the kinetic energy of the solar wind. Beams of planetary O+ ions with those properties have been detected in several orbits of the Venus Express through the wake as the spacecraft traverses by the noon-midnight plane along its near polar trajectory. The momentum flux of the O+ ions leads to superalfvenic flow conditions. It is suggested that such O+ ion beams are produced in the vicinity of the magnetic polar regions of the Venus ionosphere where the solar wind erodes the local plasma leading to plasma channels that extend downstream from those regions.

  14. Characterization of local heat fluxes around ICRF antennas on JET

    SciTech Connect (OSTI)

    Campergue, A.-L. [Ecole Nationale des Ponts et Chaussées, F77455 Marne-la-Vallée (France); Jacquet, P.; Monakhov, I.; Arnoux, G.; Brix, M.; Sirinelli, A. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Milanesio, D. [Politecnico di Torino, Department of Electronics, Torino (Italy); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Collaboration: JET-EFDA Contributors

    2014-02-12T23:59:59.000Z

    When using Ion Cyclotron Range of Frequency (ICRF) heating, enhanced power deposition on Plasma-Facing Components (PFCs) close to the antennas can occur. Experiments have recently been carried out on JET with the new ITER-Like-Wall (ILW) to characterize the heat fluxes on the protection of the JET ICRF antennas, using Infra-Red (IR) thermography measurement. The measured heat flux patterns along the poloidal limiters surrounding powered antennas were compared to predictions from a simple RF sheath rectification model. The RF electric field, parallel to the static magnetic field in front of the antenna, was evaluated using the TOPICA code, integrating a 3D flattened model of the JET A2 antennas. The poloidal density variation in front of the limiters was obtained from the mapping of the Li-beam or edge reflectometry measurements using the flux surface geometry provided by EFIT equilibrium reconstruction. In many cases, this simple model can well explain the position of the maximum heat flux on the different protection limiters and the heat-flux magnitude, confirming that the parallel RF electric field and the electron plasma density in front of the antenna are the main driving parameters for ICRF-induced local heat fluxes.

  15. Improved Calculation of Thermal Fission Energy

    E-Print Network [OSTI]

    Ma, X B; Wang, L Z; Chen, Y X; Cao, J

    2013-01-01T23:59:59.000Z

    Thermal fission energy is one of the basic parameters needed in the calculation of antineutrino flux for reactor neutrino experiments. It is useful to improve the precision of the thermal fission energy calculation for current and future reactor neutrino experiments, which are aimed at more precise determination of neutrino oscillation parameters. In this article, we give new values for thermal fission energies of some common thermal reactor fuel iso-topes, with improvements on two aspects. One is more recent input data acquired from updated nuclear databases. The other, which is unprecedented, is a consideration of the production yields of fission fragments from both thermal and fast incident neutrons for each of the four main fuel isotopes. The change in calculated antineutrino flux due to the new values of thermal fission energy is about 0.33%, and the uncertainties of the new values are about 30% smaller.

  16. Physics of String Flux Compactifications

    E-Print Network [OSTI]

    Frederik Denef; Michael R. Douglas; Shamit Kachru

    2007-01-06T23:59:59.000Z

    We provide a qualitative review of flux compactifications of string theory, focusing on broad physical implications and statistical methods of analysis.

  17. Fluxes, Gaugings and Gaugino Condensates

    E-Print Network [OSTI]

    J. -P. Derendinger; C. Kounnas; P. M. Petropoulos

    2006-02-10T23:59:59.000Z

    Based on the correspondence between the N = 1 superstring compactifications with fluxes and the N = 4 gauged supergravities, we study effective N = 1 four-dimensional supergravity potentials arising from fluxes and gaugino condensates in the framework of orbifold limits of (generalized) Calabi-Yau compactifications. We give examples in heterotic and type II orientifolds in which combined fluxes and condensates lead to vacua with small supersymmetry breaking scale. We clarify the respective roles of fluxes and condensates in supersymmetry breaking, and analyze the scaling properties of the gravitino mass.

  18. LATTICE/hor ellipsis/a beam transport program

    SciTech Connect (OSTI)

    Staples, J.

    1987-06-01T23:59:59.000Z

    LATTICE is a computer program that calculates the first order characteristics of synchrotrons and beam transport systems. The program uses matrix algebra to calculate the propagation of the betatron (Twiss) parameters along a beam line. The program draws on ideas from several older programs, notably Transport and Synch, adds many new ones and incorporates them into an interactive, user-friendly program. LATTICE will calculate the matched functions of a synchrotron lattice and display them in a number of ways, including a high resolution Tektronix graphics display. An optimizer is included to adjust selected element parameters so the beam meets a set of constraints. LATTICE is a first order program, but the effect of sextupoles on the chromaticity of a synchrotron lattice is included, and the optimizer will set the sextupole strengths for zero chromaticity. The program will also calculate the characteristics of beam transport systems. In this mode, the beam parameters, defined at the start of the transport line, are propagated through to the end. LATTICE has two distinct modes: the lattice mode which finds the matched functions of a synchrotron, and the transport mode which propagates a predefined beam through a beam line. However, each mode can be used for either type of problem: the transport mode may be used to calculate an insertion for a synchrotron lattice, and the lattice mode may be used to calculate the characteristics of a long periodic beam transport system.

  19. Neutron measurements from beam-target reactions at the ELISE neutral beam test facility

    SciTech Connect (OSTI)

    Xufei, X., E-mail: xiexufei@pku.edu.cn; Fan, T. [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Nocente, M.; Gorini, G. [Dipartimento di Fisica “G. Occhialini”, Università di Milano-Bicocca, Milano 20216 (Italy); Istituto di Fisica del Plasma “P. Caldirola”, Milano 20216 (Italy); Bonomo, F. [Consorzio RFX, Padova 35100 (Italy); Istituto Gas Ionizzati, CNR, Padova 35100 (Italy); Franzen, P.; Fröschle, M. [Max-Planck-Institut für Plasmaphysik, Garching 84518 (Germany); Grosso, G.; Tardocchi, M. [Istituto di Fisica del Plasma “P. Caldirola”, Milano 20216 (Italy); Grünauer, F. [Physics Consulting, Zorneding 85604 (Germany); Pasqualotto, R. [Consorzio RFX, Padova 35100 (Italy)

    2014-11-15T23:59:59.000Z

    Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understand neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes.

  20. Reactor Neutrino Flux Uncertainty Suppression on Multiple Detector Experiments

    E-Print Network [OSTI]

    Cucoanes, Andi; Cabrera, Anatael; Fallot, Muriel; Onillon, Anthony; Obolensky, Michel; Yermia, Frederic

    2015-01-01T23:59:59.000Z

    This publication provides a coherent treatment for the reactor neutrino flux uncertainties suppression, specially focussed on the latest $\\theta_{13}$ measurement. The treatment starts with single detector in single reactor site, most relevant for all reactor experiments beyond $\\theta_{13}$. We demonstrate there is no trivial error cancellation, thus the flux systematic error can remain dominant even after the adoption of multi-detector configurations. However, three mechanisms for flux error suppression have been identified and calculated in the context of Double Chooz, Daya Bay and RENO sites. Our analysis computes the error {\\it suppression fraction} using simplified scenarios to maximise relative comparison among experiments. We have validated the only mechanism exploited so far by experiments to improve the precision of the published $\\theta_{13}$. The other two newly identified mechanisms could lead to total error flux cancellation under specific conditions and are expected to have major implications o...

  1. Solar Model Parameters and Direct Measurements of Solar Neutrino Fluxes

    E-Print Network [OSTI]

    Abhijit Bandyopadhyay; Sandhya Choubey; Srubabati Goswami; S. T. Petcov

    2006-08-30T23:59:59.000Z

    We explore a novel possibility of determining the solar model parameters, which serve as input in the calculations of the solar neutrino fluxes, by exploiting the data from direct measurements of the fluxes. More specifically, we use the rather precise value of the $^8B$ neutrino flux, $\\phi_B$ obtained from the global analysis of the solar neutrino and KamLAND data, to derive constraints on each of the solar model parameters on which $\\phi_B$ depends. We also use more precise values of $^7Be$ and $pp$ fluxes as can be obtained from future prospective data and discuss whether such measurements can help in reducing the uncertainties of one or more input parameters of the Standard Solar Model.

  2. Beam position monitor

    DOE Patents [OSTI]

    Alkire, Randy W.; Rosenbaum, Gerold; Evans, Gwyndaf

    2003-07-22T23:59:59.000Z

    An apparatus for determining the position of an x-ray beam relative to a desired beam axis. Where the apparatus is positioned along the beam path so that a thin metal foil target intersects the x-ray beam generating fluorescent radiation. A PIN diode array is positioned so that a portion of the fluorescent radiation is intercepted by the array resulting in an a series of electrical signals from the PIN diodes making up the array. The signals are then analyzed and the position of the x-ray beam is determined relative to the desired beam path.

  3. Advanced Online Flux Mapping of CANDU PHWR by Least-Squares Method

    SciTech Connect (OSTI)

    Hong, In Seob [Seoul National University (Korea, Republic of); Kim, Chang Hyo [Seoul National University (Korea, Republic of); Suk, Ho Chun [Korea Atomic Energy Research Institute (Korea, Republic of)

    2005-07-15T23:59:59.000Z

    A least-squares method that solves both the core neutronics design equations and the in-core detector response equations on the least-squares principle is presented as a new advanced online flux-mapping method for CANada Deuterium Uranium (CANDU) pressurized heavy water reactors (PHWRs). The effectiveness of the new flux-mapping method is examined in terms of online flux-mapping calculations with numerically simulated true flux distribution and detector signals and those with the actual core-follow data for the Wolsong CANDU PHWRs in Korea. The effects of core neutronics models as well as the detector failures and uncertainties of measured detector signals on the effectiveness of the least-squares flux-mapping calculations are also examined.The following results are obtained. The least-squares method predicts the flux distribution in better agreement with the simulated true flux distribution than the standard core neutronics calculations by the finite difference method (FDM) computer code without using the detector signals. The adoption of the nonlinear nodal method based on the unified nodal method formulation instead of the FDM results in a significant improvement in prediction accuracy of the flux-mapping calculations. The detector signals estimated from the least-squares flux-mapping calculations are much closer to the measured detector signals than those from the flux synthesis method (FSM), the current online flux-mapping method for CANDU reactors. The effect of detector failures is relatively small so that the plant can tolerate up to 25% of detector failures without seriously affecting the plant operation. The detector signal uncertainties aggravate accuracy of the flux-mapping calculations, yet the effects of signal uncertainties of the order of 1% standard deviation can be tolerable without seriously degrading the prediction accuracy of the least-squares method. The least-squares method is disadvantageous because it requires longer CPU time than the existing FSM. Considering ever-increasing computer speed and the improved operational safety margin of CANDU reactors gained by accurate flux-mapping calculations, however, it is concluded that the least-squares method presents an effective alternative to the existing flux-mapping method for CANDU reactors.

  4. Original Impact Calculations

    Broader source: Energy.gov [DOE]

    Original Impact Calculations, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  5. Novel rubidium atomic beam with an alkali dispenser source

    SciTech Connect (OSTI)

    Roach, Timothy M.; Henclewood, Dwayne [College of the Holy Cross, Worcester, Massachusetts 01610 (United States)

    2004-11-01T23:59:59.000Z

    We describe a novel atomic beam apparatus with a resistively heated alkali dispenser source and a cold-pumped intermediate chamber. Using laser fluorescence spectroscopy we have measured the atomic density to be 3x10{sup 11} atoms/m{sup 3} and the total flux to be 5x10{sup 8} atoms/s in a 0.3 cm diameter beam. We have also characterized the velocity distribution of the source based on the Doppler-shifted fluorescence spectrum. The compact geometry, flexibility, and simplicity of the beam may make it useful as an optical frequency reference or for experiments on atom-cooling.

  6. The Solar Wind Energy Flux

    E-Print Network [OSTI]

    Chat, G Le; Meyer-Vernet, N

    2012-01-01T23:59:59.000Z

    The solar-wind energy flux measured near the ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10%, and that this quantity varies weakly over the solar cycle. In other words the energy flux appears as a global solar constant. We also show that the very high speed solar-wind (VSW > 700 km/s) has the same mean energy flux as the slower wind (VSW < 700 km/s), but with a different histogram. We use this result to deduce a relation between the solar-wind speed and density, which formalizes the anti-correlation between these quantities.

  7. Fermilab Hadron Test Beam and Irradia3on Facili3es

    E-Print Network [OSTI]

    McDonald, Kirk

    ­32 GeV Mixed Beam · Broadband Muons from Steel absorber/target Flux can go from beams on- site) with 3me-of- flight. #12;Booking is solid for FTBF · Experiments typically ask for 3me in 1-3 week chunks. · Ogen come back for further runs

  8. Nonclassicality of vortex Airy beams in the Wigner representation

    SciTech Connect (OSTI)

    Chen Ruipin [School of Sciences, Zhejiang A and F University, Lin'an, Zhejiang Province 311300 (China); Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Ooi, C. H. Raymond [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2011-10-15T23:59:59.000Z

    The Wigner distribution function (WDF) of a vortex Airy beam is calculated analytically. The WDF provides intuitive pictures of the intriguing features of vorticity in phase space. The nonclassical property of the vortex Airy beam and the Airy beam is analyzed through the negative parts of the WDF. The study shows that destructive interference of certain classical waves can mimic nonclassical lights such as those due to quantum effects.

  9. Observation of Disappearance of Muon Neutrinos in the NuMI Beam

    SciTech Connect (OSTI)

    Pavlovic, Zarko; /Texas U.

    2008-05-01T23:59:59.000Z

    The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation hypothesis and measure precisely {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the beam is measured at two locations, one close to the source and the other 735 km down-stream in the Soudan Mine Underground Laboratory in northern Minnesota. The precision measurement of the oscillation parameters requires an accurate prediction of the neutrino flux at the Far Detector. This thesis discusses the calculation of the neutrino flux at the Far Detector and its uncertainties. A technique that uses the Near Detector data to constrain the uncertainties in the calculation of the flux is described. The data corresponding to an exposure of 2.5 x 10{sup 20} protons on the NuMI target is presented and an energy dependent disappearance pattern predicted by neutrino oscillation hypotheses is observed in the Far Detector data. The fit to MINOS data, for given exposure, yields the best fit values for {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} to be (2.38{sub -0.16}{sup +0.20}) x 10{sup -3} eV{sup 2}/c{sup 4} and 1.00{sub -0.08}, respectively.

  10. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01T23:59:59.000Z

    interactions, ultra-high intensity lasers, 3D Laser Imagingconcepts, ultra-high intensity lasers, x-ray generation,interests: Ultra-high vacuum, particle beam and laser beam

  11. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01T23:59:59.000Z

    FEL Collaboration: Photocathode/SCRF Collaboration: Two-BeamUniversity on Photocathode/ SCRF technology, LBNL-BNL on

  12. Beam Dynamics for ARIA

    E-Print Network [OSTI]

    Ekdahl, Carl

    2015-01-01T23:59:59.000Z

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  13. Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

    E-Print Network [OSTI]

    Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

    2013-01-01T23:59:59.000Z

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  14. Effect of a spectrometer magnet on the beam-beam interaction

    SciTech Connect (OSTI)

    Cornacchia, M; Parzen, G

    1981-01-01T23:59:59.000Z

    The presence of experimental apparatus in the interaction regions of an intersecting beam accelerator changes the configuration of the crossing beams. This changes the space-charge forces with respect to the standard, magnet-free crossing. The question is: what is the maximum allowable perturbation caused by the spectrometer magnet that can be tolerated from the point of view of the beam dynamics. This paper is limited to the perturbations that the curved trajectories cause the beam-beam space charge nonlinearities. The question has arisen of how one defines the strength of the perturbation. The only solution is to compute the strength of the most important nonlinear resources. In what follows, the computational method used in calculating these resonances is described, and compared with those induced by random orbit errors.

  15. Method for measuring and controlling beam current in ion beam processing

    DOE Patents [OSTI]

    Kearney, Patrick A. (Livermore, CA); Burkhart, Scott C. (Livermore, CA)

    2003-04-29T23:59:59.000Z

    A method for producing film thickness control of ion beam sputter deposition films. Great improvements in film thickness control is accomplished by keeping the total current supplied to both the beam and suppressor grids of a radio frequency (RF) in beam source constant, rather than just the current supplied to the beam grid. By controlling both currents, using this method, deposition rates are more stable, and this allows the deposition of layers with extremely well controlled thicknesses to about 0.1%. The method is carried out by calculating deposition rates based on the total of the suppressor and beam currents and maintaining the total current constant by adjusting RF power which gives more consistent values.

  16. A High Count Rate Beam Monitor for Thermal Neutrons

    SciTech Connect (OSTI)

    Barnett, Amanda [University of Tennessee, Knoxville (UTK); Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Funk, Loren L [ORNL; Hayward, J P [University of Tennessee, Knoxville (UTK); Menhard, Kocsis [European Synchrotron Radiation Facility (ESRF); Sedov, Vladislav N [ORNL

    2012-01-01T23:59:59.000Z

    Beam monitors are an important diagnostic tool in neutron science facilities. Present beam monitors use either ionization chambers in integration mode, which are slow and have no timing information, or pulse counters which can easily be saturated by high beam intensities. Neutron beam monitors indicate the number of neutrons incident on a scattering sample and allow neutron experimental data to be analyzed even when the source strength varies with time. At high flux neutron scattering facilities, neutron beam monitors with very low efficiency (10-5) are presently selected to keep the counting rate within a feasible range, even when a higher efficiency would improve the counting statistics and yield a better measurement of the incident beam. In this work, we report on a high count rate neutron beam monitor which also offers position sensitivity to provide a beam profile. This beam monitor offers good timing (less than 1 s) in addition to position resolution and will therefore improve the counting statistics at neutron energies up to 10 eV and allow moderator studies. The detector s main characteristics will be presented including its background rate, its count rate capability which is an order of magnitude higher than present counting monitors, and its efficiency for thermal neutrons.

  17. Diffusion Simulation and Lifetime Calculation at RHIC

    SciTech Connect (OSTI)

    Abreu,N.P.; Fischer, W.; Luo, Y.; Robert-Demolaize, G.

    2009-01-02T23:59:59.000Z

    The beam lifetime is an important parameter for any storage ring. For protons in RHIC it is dominated by the non-linear nature of the head-on collisions that causes the particles to diffuse outside the stable area in phase space. In this report we show results from diffusion simulation and lifetime calculation for the 2006 and 2008 polarized proton runs in RHIC.

  18. Calculation method for safe ?* in the LHC

    E-Print Network [OSTI]

    Bruce, R; Herr, W; Wollmann, D

    2011-01-01T23:59:59.000Z

    One way of increasing the peak luminosity in the LHC is to decrease the beam size at the interaction points by squeezing to smaller values of ?*. The LHC is now in a regime where safety and stability determines the limit on ?*, as opposed to traditional optics limits. In this paper, we derive a calculation model to determine the safe ?*-values based on collimator settings and operational stability of the LHC. This model was used to calculate the settings for the LHC run in 2011. It was found that ?* could be decreased from 3.5 m to 1.5 m, which has now successfully been put into operation.

  19. The Measurement, interpretation and use of unsteady momentum fluxes in two-phase flow.

    E-Print Network [OSTI]

    Yih, Tien Sieh

    1967-01-01T23:59:59.000Z

    The steady and unsteady components of the momentum flux in a two-phase flow have been measured at the exit of a vertical pipe by means of an impulse technique using a turning tee and beam. Different electrical filters have ...

  20. Dynamic Bowtie for Fan-beam CT

    E-Print Network [OSTI]

    Liu, Fenglin; Cong, Wenxiang; Hsieh, Scott; Pelc, Norbert

    2013-01-01T23:59:59.000Z

    A bowtie is a filter used to shape an x-ray beam and equalize its flux reaching different detector channels. For development of spectral CT with energy-discriminative photon-counting (EDPC) detectors, here we propose and evaluate a dynamic bowtie for performance optimization based on a patient model or a scout scan. Our dynamic bowtie modifies an x-ray beam intensity profile by mechanical rotation and adaptive adjustment of the x-ray source flux. First, a mathematical model for dynamic bowtie filtering is established for an elliptical section in fan-beam geometry, and the contour of the optimal bowtie is derived. Then, numerical simulation is performed to compare the performance of the dynamic bowtie in the cases of an ideal phantom and a realistic cross-section relative to the counterparts without any bowtie and with a fixed bowtie respectively. Our dynamic bowtie can equalize the expected numbers of photons in the case of an ideal phantom. In practical cases, our dynamic bowtie can effectively reduce the dy...

  1. Thermality of the Hawking flux

    E-Print Network [OSTI]

    Matt Visser

    2015-02-09T23:59:59.000Z

    Is the Hawking flux "thermal"? Unfortunately, the answer to this seemingly innocent question depends on a number of often unstated, but quite crucial, technical assumptions built into modern (mis-)interpretations of the word "thermal". The original 1850's notions of thermality --- based on classical thermodynamic reasoning applied to idealized "black bodies" or "lamp black surfaces" --- when supplemented by specific basic quantum ideas from the early 1900's, immediately led to the notion of the black-body spectrum, (the Planck-shaped spectrum), but "without" any specific assumptions or conclusions regarding correlations between the quanta. Many (not all) modern authors (often implicitly and unintentionally) add an extra, and quite unnecessary, assumption that there are no correlations in the black-body radiation; but such usage is profoundly ahistorical and dangerously misleading. Specifically, the Hawking flux from an evaporating black hole, (just like the radiation flux from a leaky furnace or a burning lump of coal), is only "approximately" Planck-shaped over a bounded frequency range. Standard physics (phase space and adiabaticity effects) explicitly bound the frequency range over which the Hawking flux is "approximately" Planck-shaped from both above and below --- the Hawking flux is certainly not exactly Planckian, and there is no compelling physics reason to assume the Hawking photons are uncorrelated.

  2. Fate of False Vacuum in Superconducting Flux Qubits

    E-Print Network [OSTI]

    Ali Izadi Rad; Hesam Zandi; Mehdi Fardmanesh

    2014-11-26T23:59:59.000Z

    We propose a similarity between the scenario of fate of false vacuum in cosmology at early universe and the situation in where the quantum state decays in superconducting Flux qubit. This is due to the fact that both cases have two homogeneous stable equilibrium states in scalar field, which in quantum theory, could penetrate through the barrier in different possibilities and hence considered unstable decaying in time. In quantum computation, decay rate is among the most important factors in characteristics of the system like coherency, reliability, measurement fidelity, etc. In this considered potential, the decay rate from the penetrating (False vacuum) state to the stable (absolute minimum) state is achieved to leading order in Planck constant by the approach of Instanton model. In case of the superconducting flux qubit having thin barrier potential, the decay rate is calculated and its relations with actual set of parameters in flux qubit design are introduced.

  3. Stochastic Boundary, Diffusion, Emittance Growth and Lifetime calculation for the RHIC e-lens

    SciTech Connect (OSTI)

    Abreu,N.P.; Fischer, W.; Luo, Y.; Robert-Demolaize, G.

    2009-01-20T23:59:59.000Z

    To compensate the large tune shift and tune spread generated by the head-on beam-beam interactions in polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), a low energy electron beam with proper Gaussian transverse profiles was proposed to collide head-on with the proton beam. In this article, using a modified version of SixTrack [1], we investigate stability of the single particle in the presence of head-on beam-beam compensation. The Lyapunov exponent and action diffusion are calculated and compared between the cases without and with beam-beam compensation for two different working points and various bunch intensities. Using the action diffusion results the emittance growth rate and lifetime of the proton beam is also estimated for the different scenarios.

  4. Entanglement-assisted electron microscopy based on a flux qubit

    SciTech Connect (OSTI)

    Okamoto, Hiroshi, E-mail: okamoto@akita-pu.ac.jp [Department of Electronics and Information Systems, Akita Prefectural University, Yurihonjo 015-0055 (Japan); Nagatani, Yukinori [National Institute for Physiological Sciences, Okazaki 444-8787 (Japan)

    2014-02-10T23:59:59.000Z

    A notorious problem in high-resolution biological electron microscopy is radiation damage caused by probe electrons. Hence, acquisition of data with minimal number of electrons is of critical importance. Quantum approaches may represent the only way to improve the resolution in this context, but all proposed schemes to date demand delicate control of the electron beam in highly unconventional electron optics. Here we propose a scheme that involves a flux qubit based on a radio-frequency superconducting quantum interference device, inserted in a transmission electron microscope. The scheme significantly improves the prospect of realizing a quantum-enhanced electron microscope for radiation-sensitive specimens.

  5. LBNL-46223, CBP Note 350 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS IN THE LHC

    E-Print Network [OSTI]

    Furman, Miguel

    LBNL-46223, CBP Note 350 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS IN THE LHC M. A. Furman, W. C. Turner, Center for Beam Physics, LBNL, Berkeley, CA 94720, USA Abstract We present beam-beam simulation of simulations: (a) to as- sess undesirable effects from LBNL's luminosity monitor- ing scheme for the LHC [2

  6. LBNL-45363, CBP Note 333 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS

    E-Print Network [OSTI]

    Furman, Miguel

    LBNL-45363, CBP Note 333 BEAM-BEAM SIMULATIONS FOR SEPARATED BEAMS Miguel A. Furman, Center for Beam Physics, LBNL, Berkeley, CA 94720 Abstract We present beam-beam simulation results from a strong undesirable effects from LBNL's sweeping lumi- nosity monitoring scheme for the LHC [1], and (b) to assess

  7. High flux solar energy transformation

    DOE Patents [OSTI]

    Winston, Roland (Chicago, IL); Gleckman, Philip L. (Chicago, IL); O'Gallagher, Joseph J. (Flossmoor, IL)

    1991-04-09T23:59:59.000Z

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes.

  8. High flux solar energy transformation

    DOE Patents [OSTI]

    Winston, R.; Gleckman, P.L.; O'Gallagher, J.J.

    1991-04-09T23:59:59.000Z

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes. 7 figures.

  9. Beta ray flux measuring device

    DOE Patents [OSTI]

    Impink, Jr., Albert J. (Murrysville, PA); Goldstein, Norman P. (Murrysville, PA)

    1990-01-01T23:59:59.000Z

    A beta ray flux measuring device in an activated member in-core instrumentation system for pressurized water reactors. The device includes collector rings positioned about an axis in the reactor's pressure boundary. Activated members such as hydroballs are positioned within respective ones of the collector rings. A response characteristic such as the current from or charge on a collector ring indicates the beta ray flux from the corresponding hydroball and is therefore a measure of the relative nuclear power level in the region of the reactor core corresponding to the specific exposed hydroball within the collector ring.

  10. Quantitative high dynamic range beam profiling for fluorescence microscopy

    SciTech Connect (OSTI)

    Mitchell, T. J., E-mail: t.j.mitchell@dur.ac.uk; Saunter, C. D.; O’Nions, W.; Girkin, J. M.; Love, G. D. [Centre for Advanced Instrumentation and Biophysical Sciences Institute, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)

    2014-10-15T23:59:59.000Z

    Modern developmental biology relies on optically sectioning fluorescence microscope techniques to produce non-destructive in vivo images of developing specimens at high resolution in three dimensions. As optimal performance of these techniques is reliant on the three-dimensional (3D) intensity profile of the illumination employed, the ability to directly record and analyze these profiles is of great use to the fluorescence microscopist or instrument builder. Though excitation beam profiles can be measured indirectly using a sample of fluorescent beads and recording the emission along the microscope detection path, we demonstrate an alternative approach where a miniature camera sensor is used directly within the illumination beam. Measurements taken using our approach are solely concerned with the illumination optics as the detection optics are not involved. We present a miniature beam profiling device and high dynamic range flux reconstruction algorithm that together are capable of accurately reproducing quantitative 3D flux maps over a large focal volume. Performance of this beam profiling system is verified within an optical test bench and demonstrated for fluorescence microscopy by profiling the low NA illumination beam of a single plane illumination microscope. The generality and success of this approach showcases a widely flexible beam amplitude diagnostic tool for use within the life sciences.

  11. High Flux Isotope Reactor cold neutron source reference design concept

    SciTech Connect (OSTI)

    Selby, D.L.; Lucas, A.T.; Hyman, C.R. [and others

    1998-05-01T23:59:59.000Z

    In February 1995, Oak Ridge National Laboratory`s (ORNL`s) deputy director formed a group to examine the need for upgrades to the High Flux Isotope Reactor (HFIR) system in light of the cancellation of the Advanced neutron Source Project. One of the major findings of this study was that there was an immediate need for the installation of a cold neutron source facility in the HFIR complex. In May 1995, a team was formed to examine the feasibility of retrofitting a liquid hydrogen (LH{sub 2}) cold source facility into an existing HFIR beam tube. The results of this feasibility study indicated that the most practical location for such a cold source was the HB-4 beam tube. This location provides a potential flux environment higher than the Institut Laue-Langevin (ILL) vertical cold source and maximizes the space available for a future cold neutron guide hall expansion. It was determined that this cold neutron beam would be comparable, in cold neutron brightness, to the best facilities in the world, and a decision was made to complete a preconceptual design study with the intention of proceeding with an activity to install a working LH{sub 2} cold source in the HFIR HB-4 beam tube. During the development of the reference design the liquid hydrogen concept was changed to a supercritical hydrogen system for a number of reasons. This report documents the reference supercritical hydrogen design and its performance. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and testing, (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the conceptual design phase and establishes the baseline reference concept.

  12. Connection stiffness and dynamical docking process of flux pinned spacecraft modules

    SciTech Connect (OSTI)

    Lu, Yong; Zhang, Mingliang, E-mail: niudun12@126.com; Gao, Dong [School of Mechatronics Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001 (China)

    2014-02-14T23:59:59.000Z

    This paper describes a novel kind of potential flux pinned docking system that consists of guidance navigation and control system, the traditional extrusion type propulsion system, and a flux pinned docking interface. Because of characteristics of passive stability of flux pinning, the docking control strategy of flux pinned docking system only needs a series of sequential control rather than necessary active feedback control, as well as avoidance of hazardous collision accident. The flux pinned force between YBaCuO (YBCO) high temperature superconductor bulk and permanent magnet is able to be given vent based on the identical current loop model and improved image dipole model, which can be validated experimentally. Thus, the connection stiffness between two flux pinned spacecraft modules can be calculated based on Hooke's law. This connection stiffness matrix at the equilibrium position has the positive definite performance, which can validate the passively stable connection of two flux pinned spacecraft modules theoretically. Furthermore, the relative orbital dynamical equation of two flux pinned spacecraft modules can be established based on Clohessy-Wiltshire's equations and improved image dipole model. The dynamical docking process between two flux pinned spacecraft modules can be obtained by way of numerical simulation, which suggests the feasibility of flux pinned docking system.

  13. A FLUX SCALE FOR SOUTHERN HEMISPHERE 21 cm EPOCH OF REIONIZATION EXPERIMENTS

    SciTech Connect (OSTI)

    Jacobs, Daniel C.; Bowman, Judd [School of Earth and Space Exploration, Arizona State University, Tempe, AZ (United States); Parsons, Aaron R.; Ali, Zaki; Pober, Jonathan C. [Astronomy Department, University of California, Berkeley, CA (United States); Aguirre, James E.; Moore, David F. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA (United States); Bradley, Richard F. [Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA (United States); Carilli, Chris L. [National Radio Astronomy Observatory, Socorro, NM (United States); DeBoer, David R.; Dexter, Matthew R.; MacMahon, Dave H. E. [Radio Astronomy Lab., University of California, Berkeley, CA (United States); Gugliucci, Nicole E.; Klima, Pat [National Radio Astronomy Observatory, Charlottesville, VA (United States); Manley, Jason R.; Walbrugh, William P. [Square Kilometer Array, South Africa Project, Cape Town (South Africa); Stefan, Irina I. [Cavendish Laboratory, Cambridge (United Kingdom)

    2013-10-20T23:59:59.000Z

    We present a catalog of spectral measurements covering a 100-200 MHz band for 32 sources, derived from observations with a 64 antenna deployment of the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER) in South Africa. For transit telescopes such as PAPER, calibration of the primary beam is a difficult endeavor and errors in this calibration are a major source of error in the determination of source spectra. In order to decrease our reliance on an accurate beam calibration, we focus on calibrating sources in a narrow declination range from –46° to –40°. Since sources at similar declinations follow nearly identical paths through the primary beam, this restriction greatly reduces errors associated with beam calibration, yielding a dramatic improvement in the accuracy of derived source spectra. Extrapolating from higher frequency catalogs, we derive the flux scale using a Monte Carlo fit across multiple sources that includes uncertainty from both catalog and measurement errors. Fitting spectral models to catalog data and these new PAPER measurements, we derive new flux models for Pictor A and 31 other sources at nearby declinations; 90% are found to confirm and refine a power-law model for flux density. Of particular importance is the new Pictor A flux model, which is accurate to 1.4% and shows that between 100 MHz and 2 GHz, in contrast with previous models, the spectrum of Pictor A is consistent with a single power law given by a flux at 150 MHz of 382 ± 5.4 Jy and a spectral index of –0.76 ± 0.01. This accuracy represents an order of magnitude improvement over previous measurements in this band and is limited by the uncertainty in the catalog measurements used to estimate the absolute flux scale. The simplicity and improved accuracy of Pictor A's spectrum make it an excellent calibrator in a band important for experiments seeking to measure 21 cm emission from the epoch of reionization.

  14. Magnetic field-line lengths inside interplanetary magnetic flux ropes

    E-Print Network [OSTI]

    Hu, Qiang; Krucker, Sam

    2015-01-01T23:59:59.000Z

    We report on the detailed and systematic study of field-line twist and length distributions within magnetic flux ropes embedded in Interplanetary Coronal Mass Ejections (ICMEs). The Grad-Shafranov reconstruction method is utilized together with a constant-twist nonlinear force-free (Gold-Hoyle) flux rope model to reveal the close relation between the field-line twist and length in cylindrical flux ropes, based on in-situ Wind spacecraft measurements. We show that the field-line twist distributions within interplanetary flux ropes are inconsistent with the Lundquist model. In particular we utilize the unique measurements of magnetic field-line lengths within selected ICME events as provided by Kahler et al. (2011) based on energetic electron burst observations at 1 AU and the associated type III radio emissions detected by the Wind spacecraft. These direct measurements are compared with our model calculations to help assess the flux-rope interpretation of the embedded magnetic structures. By using the differen...

  15. QUANTIFICATION OF HEAT FLUX FROM A REACTING THERMITE SPRAY

    SciTech Connect (OSTI)

    Eric Nixon; Michelle Pantoya

    2009-07-01T23:59:59.000Z

    Characterizing the combustion behaviors of energetic materials requires diagnostic tools that are often not readily or commercially available. For example, a jet of thermite spray provides a high temperature and pressure reaction that can also be highly corrosive and promote undesirable conditions for the survivability of any sensor. Developing a diagnostic to quantify heat flux from a thermite spray is the objective of this study. Quick response sensors such as thin film heat flux sensors can not survive the harsh conditions of the spray, but more rugged sensors lack the response time for the resolution desired. A sensor that will allow for adequate response time while surviving the entire test duration was constructed. The sensor outputs interior temperatures of the probes at known locations and utilizes an inverse heat conduction code to calculate heat flux values. The details of this device are discussed and illustrated. Temperature and heat flux measurements of various thermite spray conditions are reported. Results indicate that this newly developed energetic material heat flux sensor provides quantitative data with good repeatability.

  16. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14T23:59:59.000Z

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  17. Higher order treatment on temporal derivative of angular flux for time-dependent MOC

    SciTech Connect (OSTI)

    Tsujita, K.; Endo, T.; Yamamoto, A. [Nagoya University, Department of Material, Physics and Energy Engineering, Furo-cho, Chikusa-ku, Nagoya, 464-8603 (Japan); Kamiyama, Y.; Kirimura, K. [Mitsubishi Heavy Industries, Ltd., Wadasakicho1-1-1, Hyogo-ku, Kobe, 652-8585 (Japan)

    2013-07-01T23:59:59.000Z

    A new kinetic analysis method, whose angular dependence of temporal derivative for angular flux is accurately treated within practical memory requirement, is proposed. The method of characteristics (MOC) is being widely used for reactor analysis thanks to the advances of numerical algorithms and computer hardware. However, the computational resources, i.e., the memory capacity, can be still a crucial problem for rigorous kinetic calculations using MOC. In the straightforward approach for kinetic calculation using MOC, the segment-averaged angular fluxes should be stored on the memory in order to explicitly calculate the temporal derivative of the angular flux, which would require huge memory. Thus, in the conventional kinetic calculation code using MOC, the temporal derivative of the angular flux has been approximated as angularly isotropic in order to reduce the memory requirement (isotropic assumption). However, the approximation error caused by the conventional isotropic assumption has not been thoroughly and quantitatively investigated so far and an accurate kinetic calculation method, which can quantitatively estimate the above approximation error within practical memory storage, has not been developed. The present study tries to address this issue with a newly developed approach. Effect of the approximate treatment for the temporal derivative of angular flux is evaluated through benchmark calculations. (authors)

  18. Rate constants from the reaction path Hamiltonian. I. Reactive flux simulations for dynamically correct rates

    E-Print Network [OSTI]

    Bell, Alexis T.

    As ab initio electronic structure calculations become more accurate, inherent sources of error, facilitate reactive flux calculations. As an example we compute the dynamically corrected rate constant on which the reaction occurs. A large number of electronic structure theo- ries are available

  19. Methods of Beam Cooling

    E-Print Network [OSTI]

    Sessler, A. M.

    2008-01-01T23:59:59.000Z

    of Optical Stochastic Cooling", presented at PAC, (1995).1991). Hangst, J. , "Laser Cooling of a Stored Ion Beam - ATheorem and Phase Space Cooling", Proceedings of the

  20. Broad beam ion implanter

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    1996-01-01T23:59:59.000Z

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes.

  1. Courses on Beam Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is an incomplete listing of course available for beam physics. United States Particle Accelerator School The US Particle Accelerator School provides educational programs in the...

  2. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

  3. Quantum Fusion of Domain Walls with Fluxes

    E-Print Network [OSTI]

    S. Bolognesi; M. Shifman; M. B. Voloshin

    2009-07-20T23:59:59.000Z

    We study how fluxes on the domain wall world volume modify quantum fusion of two distant parallel domain walls into a composite wall. The elementary wall fluxes can be separated into parallel and antiparallel components. The parallel component affects neither the binding energy nor the process of quantum merger. The antiparallel fluxes, instead, increase the binding energy and, against naive expectations, suppress quantum fusion. In the small flux limit we explicitly find the bounce solution and the fusion rate as a function of the flux. We argue that at large (antiparallel) fluxes there exists a critical value of the flux (versus the difference in the wall tensions), which switches off quantum fusion altogether. This phenomenon of flux-related wall stabilization is rather peculiar: it is unrelated to any conserved quantity. Our consideration of the flux-related all stabilization is based on substantiated arguments that fall short of complete proof.

  4. Beam Test of a Segmented Foil SEM Grid

    E-Print Network [OSTI]

    S. Kopp; D. Indurthy; Z. Pavlovich; M. Proga; R. Zwaska; S. Childress; R. Ford; C. Kendziora; T. Kobilarcik; C. Moore; G. Tassotto

    2005-07-29T23:59:59.000Z

    A prototype Secondary-electron Emission Monitor (SEM) was installed in the 8 GeV proton transport line for the MiniBooNE experiment at Fermilab. The SEM is a segmented grid made with 5 um Ti foils, intended for use in the 120 GeV NuMI beam at Fermilab. Similar to previous workers, we found that the full collection of the secondary electron signal requires a bias voltage to draw the ejected electrons cleanly off the foils, and this effect is more pronounced at larger beam intensity. The beam centroid and width resolutions of the SEM were measured at beam widths of 3, 7, and 8 mm, and compared to calculations. Extrapolating the data from this beam test, we expect a centroid and width resolutions of 20um and 25 um, respectively, in the NuMI beam which has 1 mm spot size.

  5. A High Count Rate Neutron Beam Monitor for Neutron Scattering Facilities

    SciTech Connect (OSTI)

    Barnett, Amanda [University of Tennessee, Knoxville (UTK); Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Hayward, J P [University of Tennessee, Knoxville (UTK); Hayward, Jason P [ORNL; Menhard, Kocsis [European Synchrotron Radiation Facility (ESRF); Sedov, Vladislav N [ORNL; Funk, Loren L [ORNL

    2013-01-01T23:59:59.000Z

    Abstract Beam monitors are an important diagnostic tool in neutron science facilities. Present beam monitors use either ionization chambers in integration mode, which are slow and have no timing information, or pulse counters which can easily be saturated by high beam intensities. At high flux neutron scattering facilities, neutron beam monitors with very low intrinsic efficiency (10-5) are presently selected to keep the counting rate within a feasible range, even when a higher efficiency would improve the counting statistics and yield a better measurement of the incident beam. In this work, we report on a high count rate neutron beam monitor. This beam monitor offers good timing with an intrinsic efficiency of 10-3 and a counting rate capability of over 1,000,000 cps without saturation.

  6. Scaling of solid state lasers for satellite power beaming applications

    SciTech Connect (OSTI)

    Friedman, H.W.; Albrecht, G.F.; Beach, R.J.

    1994-01-01T23:59:59.000Z

    The power requirements for a satellite power beaming laser system depend upon the diameter of the beam director, the performance of the adaptive optics system, and the mission requirements. For an 8 meter beam director and overall Strehl ratio of 50%, a 30 kW laser at 850 nm can deliver an equivalent solar flux to a satellite at geostationary orbit. Advances in Diode Pumped Solid State Lasers (DPSSL) have brought these small, efficient and reliable devices to high average power and they should be considered for satellite power beaming applications. Two solid state systems are described: a diode pumped Alexandrite and diode pumped Thulium doped YAG. Both can deliver high average power at 850 nm in a single aperture.

  7. An Analysis of Fluxes by Duality

    E-Print Network [OSTI]

    Paul S. Aspinwall

    2005-04-05T23:59:59.000Z

    M-theory on K3xK3 with non-supersymmetry-breaking G-flux is dual to M-theory on a Calabi-Yau threefold times a 2-torus without flux. This allows for a thorough analysis of the effects of flux without relying on supergravity approximations. We discuss several dual pairs showing that the usual rules of G-flux compactifications work well in detail. We discuss how a transition can convert M2-branes into G-flux. We see how new effects can arise at short distances allowing fluxes to obstruct more moduli than one expects from the supergravity analysis.

  8. Spatially resolved temperature and heat flux measurements for slow evaporating droplets heated by a microfabricated heater array

    E-Print Network [OSTI]

    Paik, Sokwon

    2006-08-16T23:59:59.000Z

    flux datum per one droplet. No spatial or temporal heat flux information was given. Klassen et al. [12] and di Marzo et al. [13] were the first to use an infrared thermography technique to attempt to measure the spatially and temporally resolved... infrared thermography. Because of the aforementioned limitation of the IR thermography, measurements were only possible outside of the droplets. Michiyoshi and Makino [15] used a dual beam synchroscope to measure the variation of the heater supply...

  9. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1994-02-15T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus is described. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 7 figures.

  10. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, B.E.; Duncan, D.B.

    1993-12-28T23:59:59.000Z

    Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 11 figures.

  11. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    SciTech Connect (OSTI)

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20T23:59:59.000Z

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  12. First Beam to FACET

    SciTech Connect (OSTI)

    Erickson, R.; Clarke, C.; Colocho, W.; Decker, F.-J.; Hogan, M.; Kalsi, S.; Lipkowitz, N.; Nelson, J.; Phinney, N.; Schuh, P.; Sheppard, J.; Smith, H.; Smith, T.; Stanek, M.; Turner, J.; Warren, J.; Weathersby, S.; Wienands, U.; Wittmer, W.; Woodley, M.; Yocky, G.; /SLAC

    2011-12-13T23:59:59.000Z

    The SLAC 3km linear electron accelerator has been reconfigured to provide a beam of electrons to the new Facility for Advanced Accelerator Experimental Tests (FACET) while simultaneously providing an electron beam to the Linac Coherent Light Source (LCLS). On June 23, 2011, the first electron beam was transported through this new facility. Commissioning of FACET is in progress. On June 23, 2011, an electron beam was successfully transported through the new FACET system to a dump in Sector 20 in the linac tunnel. This was achieved while the last third of the linac, operating from the same control room, but with a separate injector system, was providing an electron beam to the Linac Coherent Light Source (LCLS), demonstrating that concurrent operation of the two facilities is practical. With the initial checkout of the new transport line essentially complete, attention is now turning toward compressing the electron bunches longitudinally and focusing them transversely to support a variety of accelerator science experiments.

  13. Heisenberg groups and noncommutative fluxes

    SciTech Connect (OSTI)

    Freed, Daniel S. [Department of Mathematics, University of Texas at Austin, TX 78712 (United States)]. E-mail: dafr@math.utexas.edu; Moore, Gregory W. [Department of Physics, Rutgers University, Piscataway, NJ 08854-8019 (United States); Segal, Graeme [All Souls College, Oxford (United Kingdom)

    2007-01-15T23:59:59.000Z

    We develop a group-theoretical approach to the formulation of generalized abelian gauge theories, such as those appearing in string theory and M-theory. We explore several applications of this approach. First, we show that there is an uncertainty relation which obstructs simultaneous measurement of electric and magnetic flux when torsion fluxes are included. Next, we show how to define the Hilbert space of a self-dual field. The Hilbert space is Z{sub 2}-graded and we show that, in general, self-dual theories (including the RR fields of string theory) have fermionic sectors. We indicate how rational conformal field theories associated to the two-dimensional Gaussian model generalize to (4k+2)-dimensional conformal field theories. When our ideas are applied to the RR fields of string theory we learn that it is impossible to measure the K-theory class of a RR field. Only the reduction modulo torsion can be measured.

  14. Beam optics issues for the antiproton decelerator

    E-Print Network [OSTI]

    Belochitskii, P; Eriksson, T; Giannini, R; Maury, S; Möhl, D; Pedersen, F

    1998-01-01T23:59:59.000Z

    The deceleration of the beam down to 0.1 GeV/c in the ring previously used as Antiproton Collector (AC) at 3.5 GeV/c, requires a number of modifications to the lattice. The insertion of the electron cooling, needed to cool the antiproton beam at low energy, implies the re-arrange-ment of quadrupoles. The optical functions then need to be readjusted in order to keep the large acceptance and to cope with the electron and stochastic cooling environ-ment. Calculations of the linear optics and of the accep-tance are reported. Tests of beam deceleration in the AC show the need for closed-orbit correction at low momentum in addition to the static correction by the movement of the quadrupoles available in the present configuration. The deceleration tests will be discussed and a correction system, which includes trim supplies on the main bending magnets, will be described.

  15. BEAM EMITTANCE MEASUREMENT TOOL FOR CEBAF OPERATIONS

    SciTech Connect (OSTI)

    Chevtsov, Pavel; Tiefenback, Michael

    2008-10-01T23:59:59.000Z

    A new software tool was created at Jefferson Lab to measure the emittance of the CEBAF electron beams. The tool consists of device control and data analysis applications. The device control application handles the work of wire scanners and writes their measurement results as well as the information about accelerator settings during these measurements into wire scanner data files. The data analysis application reads these files and calculates the beam emittance on the basis of a wire scanner data processing model. Both applications are computer platform independent but are mostly used on LINUX PCs recently installed in the accelerator control room. The new tool significantly simplifies beam emittance measurement procedures for accelerator operations and contributes to a very high availability of the CEBAF machine for the nuclear physics program at Jefferson Lab.

  16. ARM - Measurement - Soil moisture flux

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat flux ARM Data Discovery Browse Data

  17. Scanning Tunneling Microscopy Study of Cr-doped GaN Surface Grown by RF Plasma Molecular Beam Epitaxy

    E-Print Network [OSTI]

    on sapphire substrate [2]. Park et al. performed the growth of Cr doped GaN single crystal by sodium fluxScanning Tunneling Microscopy Study of Cr-doped GaN Surface Grown by RF Plasma Molecular Beam Orleans, New Orleans, LA 70148, USA Abstract: Cr doped GaN was grown by rf N-plasma molecular beam epitaxy

  18. STOCHASTIC COOLING OF BUNCHED BEAMS

    E-Print Network [OSTI]

    Bisognano, J.J.

    2010-01-01T23:59:59.000Z

    March 11-13, 1981 STOCHASTIC COOLING OF BUNCHED BEAMS J.J.W-7406-BW-48 STOCHASTIC COOLING OF BUNCHED BEAMS* J.J.longitudinal stochastic cooling of bunched particle beams.

  19. Center vortices as composites of monopole fluxes

    E-Print Network [OSTI]

    Deldar, Sedigheh

    2015-01-01T23:59:59.000Z

    We study the relation between the flux of a center vortex obtained from the center vortex model and the flux formed between monopoles obtained from the Abelian gauge fixing method. Motivated by the Monte Carlo simulations which have shown that almost all monopoles are sitting on the top of vortices, we construct the fluxes of center vortices for $SU(2)$ and $SU(3)$ gauge groups using fractional fluxes of monopoles. Then, we compute the potentials in the fundamental representation induced by center vortices and fractional fluxes of monopoles. We show that by combining the fractional fluxes of monopoles one can produce the center vortex fluxes for $SU(3)$ gauge group in a "center vortex model". Comparing the potentials, we conclude that the fractional fluxes of monopoles attract each other.

  20. Reactor Neutrino Flux Uncertainty Suppression on Multiple Detector Experiments

    E-Print Network [OSTI]

    Andi Cucoanes; Pau Novella; Anatael Cabrera; Muriel Fallot; Anthony Onillon; Michel Obolensky; Frederic Yermia

    2015-01-02T23:59:59.000Z

    This publication provides a coherent treatment for the reactor neutrino flux uncertainties suppression, specially focussed on the latest $\\theta_{13}$ measurement. The treatment starts with single detector in single reactor site, most relevant for all reactor experiments beyond $\\theta_{13}$. We demonstrate there is no trivial error cancellation, thus the flux systematic error can remain dominant even after the adoption of multi-detector configurations. However, three mechanisms for flux error suppression have been identified and calculated in the context of Double Chooz, Daya Bay and RENO sites. Our analysis computes the error {\\it suppression fraction} using simplified scenarios to maximise relative comparison among experiments. We have validated the only mechanism exploited so far by experiments to improve the precision of the published $\\theta_{13}$. The other two newly identified mechanisms could lead to total error flux cancellation under specific conditions and are expected to have major implications on the global $\\theta_{13}$ knowledge today. First, Double Chooz, in its final configuration, is the only experiment benefiting from a negligible reactor flux error due to a $\\sim$90\\% geometrical suppression. Second, Daya Bay and RENO could benefit from their partial geometrical cancellation, yielding a potential $\\sim$50\\% error suppression, thus significantly improving the global $\\theta_{13}$ precision today. And third, we illustrate the rationale behind further error suppression upon the exploitation of the inter-reactor error correlations, so far neglected. So, our publication is a key step forward in the context of high precision neutrino reactor experiments providing insight on the suppression of their intrinsic flux error uncertainty, thus affecting past and current experimental results, as well as the design of future experiments.

  1. Uncertainty of calorimeter measurements at NREL's high flux solar furnace

    SciTech Connect (OSTI)

    Bingham, C.E.

    1991-12-01T23:59:59.000Z

    The uncertainties of the calorimeter and concentration measurements at the High Flux Solar Furnace (HFSF) at the National Renewable Energy Laboratory (NREL) are discussed. Two calorimeter types have been used to date. One is an array of seven commercially available circular foil calorimeters (gardon or heat flux gages) for primary concentrator peak flux (up to 250 W/cm{sup 2}). The second is a cold-water calorimeter designed and built by the University of Chicago to measure the average exit power of the reflective compound parabolic secondary concentrator used at the HFSF (over 3.3 kW across a 1.6cm{sup {minus}2} exit aperture, corresponding to a flux of about 2 kW/cm{sup 2}). This paper discussed the uncertainties of the calorimeter and pyrheliometer measurements and resulting concentration calculations. The measurement uncertainty analysis is performed according to the ASME/ANSI standard PTC 19.1 (1985). Random and bias errors for each portion of the measurement are analyzed. The results show that as either the power or the flux is reduced, the uncertainties increase. Another calorimeter is being designed for a new, refractive secondary which will use a refractive material to produce a higher average flux (5 kW/cm{sup 2}) than the reflective secondary. The new calorimeter will use a time derivative of the fluid temperature as a key measurement of the average power out of the secondary. A description of this calorimeter and test procedure is also presented, along with a pre-test estimate of major sources of uncertainty. 8 refs., 4 figs., 3 tabs.

  2. Calculating LHC Tuning Knobs using Various Methods

    E-Print Network [OSTI]

    Wittmer, W; Zimmermann, Frank

    2004-01-01T23:59:59.000Z

    By measuring and adjusting the beta-functions at the IP the luminosity is being optimized. In LEP this was done with the two closest doublet magnets. This approach is not applicable for the LHC due to the asymmetric lattice and common beam pipe through the triplet magnets. To control and change the beta-functions quadrupole groups situated on both sides further away from the IP have to be used where the two beams are already separated. The quadrupoles are excited in specific linear combinations, forming the socalled “tuning knobs” for the IP beta functions. We compare the performance of such knobs calculated by different methods: (1) matching in MAD, (2) inversion of the response matrix and singular value decomposition inversion and conditioning and (3) conditioning the response matrix by multidimensional minimization using an Adapted Moore Penrose Method.

  3. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-06-16T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a challenging endeavor. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6$\\,$s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1$\\,$Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based BEC experiments while offering significantly higher repetition rates. Additionally, the flux is approaching those of current interferometers employing Raman-type velocity selection of laser-cooled atoms. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for transportable high-precision quantum sensors.

  4. Single Crystal Diamond Beam Position Monitors with Radiofrequency Electronic Readout

    SciTech Connect (OSTI)

    Solar, B.; Graafsma, H.; Potdevin, G.; Trunk, U. [Hasylab, Deutsches Elektronen Synchroton, Hamburg (Germany); Morse, J.; Salome, M. [Instrumentation Services and Development Division, European Synchroton Radiation Facility, Grenoble (France)

    2010-06-23T23:59:59.000Z

    Over the energy range 5{approx}30 keV a suitably contacted, thin ({approx}100 {mu}m) diamond plate can be operated in situ as a continuous monitor of X-ray beam intensity and position as the diamond absorbs only a small percentage of the incident beam. Single crystal diamond is a completely homogeneous material showing fast (ns), spatially uniform signal response and negligible (beams. We report on tests made at ESRF and DESY using diamond beam position monitors of simple quadrant electrode designs with metal contacts, operated using wideband electronic readout corresponding to the RF accelerator frequency. The instrumentation for these monitors must cover a large range of operating conditions: different beam sizes, fluxes, energies and time structure corresponding to the synchrotron fill patterns. Sophisticated new RF sampling electronics can satisfy most requirements: using a modified Libera Brilliance readout system, we measured the center of gravity position of a 25 {mu}m beam at the DORIS III F4 beam line at a rate of 130 Msample/s with narrowband filtering of a few MHz bandwidth. Digitally averaging the signal further provided a spatial resolution {approx}20 nm.

  5. FFTF (Fast Flux Test Facility) cobalt test assembly results

    SciTech Connect (OSTI)

    Rawlins, J.A.; Wootan, D.W.; Carter, L.L.; Brager, H.R.; Schenter, R.E.

    1987-10-01T23:59:59.000Z

    A cobalt test assembly containing yttrium hydride pins for neutron moderation was irradiated in the Fast Flux Test Facility during Cycle 9A for 137.7 equivalent full power days at a power level of 291 MW. The 36 test pins consisted of a batch of 32 pins containing cobalt metal to produce Co-60, and a set of 4 pins with europium oxide to produce Gd-153, a radioisotope used in detection of the bone disease Osteoporosis. Post-irradiation examination of the cobalt pins determined the Co-60 produced with an accuracy of about 5%. The measured Co-60 spatially distributed concentrations were within 20% of the calculated concentrations. The assembly average Co-60 measured activity was 4% less than the calculated value. The europium oxide pins were gamma scanned for the europium isotopes Eu-152 and Eu-154 to an absolute accuracy of about 10%. The measured europium radioisotope and Gd-153 concentrations were within 20% of calculated values. In conclusion, the hydride assembly performed well and is an excellent vehicle for many Fast Flux Test Facility isotope production applications. The results also demonstrate that the calculational methods developed by the Westinghouse Hanford Company are very accurate. 4 refs., 3 figs., 1 tab.

  6. Solar radiation intensity calculations

    E-Print Network [OSTI]

    Levine, Randolph Steven

    1978-01-01T23:59:59.000Z

    SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Submitted to the Graduate College of Texas A&M University in partia'l fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject...: Physics SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Approved as to style and content by: (Chairman of Committee) (Member) (Member) ( member) (Head of Department) December 1978 f219 037 ABSTRACT Solar Radiation...

  7. Source Terms for HFIR Beam Tube Shielding Analyses, and a Complete Shielding Analysis of the HB-3 Tube

    SciTech Connect (OSTI)

    Bucholz, J.A.

    2000-07-01T23:59:59.000Z

    The High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory is in the midst of a massive upgrade program to enhance experimental facilities. The reactor presently has four horizontal experimental beam tubes, all of which will be replaced or redesigned. The HB-2 beam tube will be enlarged to support more guide tubes, while the HB-4 beam tube will soon include a cold neutron source.

  8. Validation of the Read Out Electronics for the CMS Muon Drift Chambers at Tests Beam in CERN/GIF

    E-Print Network [OSTI]

    Fernández, C; Fouz-Iglesias, M C; Marin, J; Oller, J C; Willmott, C

    2002-01-01T23:59:59.000Z

    Part of the readout system for the CMS muon drift chambers has been tested in test beams at CERN/GIF. Read Out Board (ROB) and HPTD have been validated with signals from a real muon beam, with an structure and flux similar to LHC operating conditions and using one of the chambers produced in CIEMAT already located in the test beam area under normal gas and voltage conditions. (Author) 5 refs.

  9. Simulations of beam-beam and beam-wire interactions in RHIC

    SciTech Connect (OSTI)

    Kim, Hyung J.; Sen, Tanaji; /Fermilab; Abreu, Natalia P.; Fischer, Wolfram; /Brookhaven

    2009-02-01T23:59:59.000Z

    The beam-beam interaction is one of the dominant sources of emittance growth and luminosity lifetime deterioration. A current carrying wire has been proposed to compensate long-range beam-beam effects in the LHC and strong localized long-range beam-beam effects are experimentally investigated in the RHIC collider. Tune shift, beam transfer function, and beam loss rate are measured in dedicated experiments. In this paper, they report on simulations to study the effect of beam-wire interactions based on diffusive apertures, beam loss rates, and beam transfer function using a parallelized weak-strong beam simulation code (BBSIMC). The simulation results are compared with measurements performed in RHIC during 2007 and 2008.

  10. Ion beam lithography system

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-08-02T23:59:59.000Z

    A maskless plasma-formed ion beam lithography tool provides for patterning of sub-50 nm features on large area flat or curved substrate surfaces. The system is very compact and does not require an accelerator column and electrostatic beam scanning components. The patterns are formed by switching beamlets on or off from a two electrode blanking system with the substrate being scanned mechanically in one dimension. This arrangement can provide a maskless nano-beam lithography tool for economic and high throughput processing.

  11. Airborne flux measurements of Biogenic Isoprene over California

    SciTech Connect (OSTI)

    Misztal, P.; Karl, Thomas G.; Weber, Robin; Jonsson, H. H.; Guenther, Alex B.; Goldstein, Allen H.

    2014-10-10T23:59:59.000Z

    Biogenic Volatile Organic Compound (BVOC) fluxes were measured onboard the CIRPAS Twin Otter aircraft as part of the California Airborne BVOC Emission Research in Natural Ecosystem Transects (CABERNET) campaign during June 2011. The airborne virtual disjunct eddy covariance (AvDEC) approach used measurements from a PTR-MS and a wind radome probe to directly determine fluxes of isoprene, MVK+MAC, methanol, monoterpenes, and MBO over ~10,000-km of flight paths focusing on areas of California predicted to have the largest emissions of isoprene. The Fast Fourier Transform (FFT) approach was used to calculate fluxes over long transects of more than 15 km, most commonly between 50 and 150 km. The Continuous Wavelet Transformation (CWT) approach was used over the same transects to also calculate "instantaneous" fluxes with localization of both frequency and time independent of non-stationarities. Vertical flux divergence of isoprene is expected due to its relatively short lifetime and was measured directly using "racetrack" profiles at multiple altitudes. It was found to be linear and in the range 5% to 30% depending on the ratio of aircraft altitude to PBL height (z/zi). Fluxes were generally measured by flying consistently 1 at 400 m ±50 m (a.g.l.) altitude, and extrapolated to the surface according to the determined flux divergence. The wavelet-derived surface fluxes of isoprene averaged to 2 km spatial resolution showed good correspondence to Basal Emission Factor (BEF) landcover datasets used to drive biogenic VOC (BVOC) emission models. The surface flux of isoprene was close to zero over Central Valley crops and desert shrublands, but was very high (up to 15 mg m-2 h-1) above oak woodlands, with clear dependence of emissions on temperature and oak density. Isoprene concentrations of up to 8 ppb were observed at aircraft height on the hottest days and over the dominant source regions. While isoprene emissions from agricultural crop regions, shrublands, and coniferous forests were extremely low, high concentrations of methanol and monoterpenes were found above some of these regions. These observations demonstrate the ability to measure fluxes from specific sources by eddy covariance from an aircraft, and suggest the utility of measurements using fast response chemical sensors to constrain emission inventories and map out source distributions for a much broader array of trace gases than was observed in this study. This paper reports the first regional direct eddy covariance fluxes of isoprene. The emissions of VOCs measured from aircraft with 2 km spatial resolution can quantify the distribution of major sources providing the observations required for testing statewide emission inventories of these important trace gases. These measurements will be used in a future study to assess BVOC emission models and their driving variable datasets.

  12. High Heat Flux Thermoelectric Module Using Standard Bulk Material...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat Flux Thermoelectric Module Using Standard Bulk Material High Heat Flux Thermoelectric Module Using Standard Bulk Material Presents high heat flux thermoelectric module design...

  13. Estimation of advective fluxes from CO2 flux profile observations at the Cabauw Tower

    E-Print Network [OSTI]

    Stoffelen, Ad

    Estimation of advective fluxes from CO2 flux profile observations at the Cabauw Tower Kasper O profile observations at the Cabauw Tower Version 1.0 Date April 2012 Status Final #12;#12;Estimation of Advective Fluxes from CO2 Flux Profile Observations at the Cabauw Tower Master of Science Thesis Kasper O

  14. Coherent beam-beam mode in the LHC

    E-Print Network [OSTI]

    Buffat, X; Giachino, R; Herr, W; Papotti, G; Pieloni, T; White, S

    2014-01-01T23:59:59.000Z

    Observations of single bunch beam-beam coherent modes during dedicated experiments in the LHC are presented. Their role in standard operation for physics is discussed and, in particular, candidates of beam-beam coherent mode driven unstable by the machine impedance are presented.

  15. Polarization diagnostics of proton beams in solar flares

    E-Print Network [OSTI]

    Jiri Stepan

    2007-02-02T23:59:59.000Z

    We review the problem of proton beam bombardment of solar chromosphere considering the self-consistent NLTE polarized radiation transfer in hydrogen lines. Several observations indicate a linear polarization of the H-alpha line of the order of 5% or higher and preferentially in radial direction. This polarization is often explained as anisotropic collisional excitation of the n=3 level by vertical proton beams. Our calculations indicate that deceleration of the proton beam with initial power-law energy distribution together with increased electron and proton densities in the H-alpha forming layers lead to a negligible line polarization. Thus the proton beams seem not to be a good candidate for explanation of the observed polarization degree. On the other hand, the effect of electric return currents could perhaps provide a better explanation of the observed linear polarization. We report the new calculations of this effect.

  16. Focused ion beam system

    DOE Patents [OSTI]

    Leung, K.; Gough, R.A.; Ji, Q.; Lee, Y.Y.

    1999-08-31T23:59:59.000Z

    A focused ion beam (FIB) system produces a final beam spot size down to 0.1 {mu}m or less and an ion beam output current on the order of microamps. The FIB system increases ion source brightness by properly configuring the first (plasma) and second (extraction) electrodes. The first electrode is configured to have a high aperture diameter to electrode thickness aspect ratio. Additional accelerator and focusing electrodes are used to produce the final beam. As few as five electrodes can be used, providing a very compact FIB system with a length down to only 20 mm. Multibeamlet arrangements with a single ion source can be produced to increase throughput. The FIB system can be used for nanolithography and doping applications for fabrication of semiconductor devices with minimum feature sizes of 0.1 m or less. 13 figs.

  17. Final focus test beam

    SciTech Connect (OSTI)

    Not Available

    1991-03-01T23:59:59.000Z

    This report discusses the following: the Final Focus Test Beam Project; optical design; magnets; instrumentation; magnetic measurement and BPM calibration; mechanical alignment and stabilization; vacuum system; power supplies; control system; radiation shielding and personnel protection; infrastructure; and administration.

  18. ARM - Measurement - Soil heat flux

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat flux ARM Data Discovery Browse Data Comments? We

  19. LHC beam behaviour

    E-Print Network [OSTI]

    Herr, W

    2010-01-01T23:59:59.000Z

    An attempt is made to extract information on the LHC beam behaviour and dynamics from the observations made during the first runs in 2009. Although no systematic studies have been made, some basic properties can be established and in particular the observations in the presence of two beams and in collision are studied. They are analyzed in view of the foreseen runs at higher energy and possible improvements are proposed.

  20. Wire Scanner Beam Profile Measurements: LANSCE Facility Beam Development

    SciTech Connect (OSTI)

    Gilpatrick, John D. [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gonzales, Fermin [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Kutac, Vincent G. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

    2012-05-15T23:59:59.000Z

    The Los Alamos Neutron Science Center (LANSCE) is replacing Wire Scanner (WS) beam profile measurement systems. Three beam development tests have taken place to test the new wire scanners under beam conditions. These beam development tests have integrated the WS actuator, cable plant, electronics processors and associated software and have used H{sup -} beams of different beam energy and current conditions. In addition, the WS measurement-system beam tests verified actuator control systems for minimum profile bin repeatability and speed, checked for actuator backlash and positional stability, tested the replacement of simple broadband potentiometers with narrow band resolvers, and tested resolver use with National Instruments Compact Reconfigurable Input and Output (cRIO) Virtual Instrumentation. These beam tests also have verified how trans-impedance amplifiers react with various types of beam line background noise and how noise currents were not generated. This paper will describe these beam development tests and show some resulting data.

  1. Fan-beam intensity modulated proton therapy

    SciTech Connect (OSTI)

    Hill, Patrick [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States)] [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Westerly, David [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Mackie, Thomas [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)] [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques.Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets.Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal falloff of a proton depth-dose distribution was found to provide sufficient control over the dose distribution to meet objectives, even with coarse lateral resolution and channel widths as large as 2 cm. Treatment plans on both phantom and patient data show that dose conformity suffers when treatments are delivered from less than approximately ten angles. Treatment time for a sample prostate delivery is estimated to be on the order of 10 min, and neutron production is estimated to be comparable to that found for existing collimated systems.Conclusions: Fan beam proton therapy is a method of delivering intensity modulated proton therapy which may be employed as an alternative to magnetic scanning systems. A fan beam of protons can be created by a set of quadrupole magnets and modified by a dual-purpose range and intensity modulator. This can be used to deliver inversely planned treatments, with spot intensities optimized to meet user defined dose objectives. Additionally, the ability of a fan beam delivery system to effectively treat multiple beam spots simultaneously may provide advantages as compared to spot scanning deliveries.

  2. Method of fission heat flux determination from experimental data

    DOE Patents [OSTI]

    Paxton, Frank A. (Schenectady, NY)

    1999-01-01T23:59:59.000Z

    A method is provided for determining the fission heat flux of a prime specimen inserted into a specimen of a test reactor. A pair of thermocouple test specimens are positioned at the same level in the holder and a determination is made of various experimental data including the temperature of the thermocouple test specimens, the temperature of bulk water channels located in the test holder, the gamma scan count ratios for the thermocouple test specimens and the prime specimen, and the thicknesses of the outer clads, the fuel fillers, and the backclad of the thermocouple test specimen. Using this experimental data, the absolute value of the fission heat flux for the thermocouple test specimens and prime specimen can be calculated.

  3. Single element laser beam shaper

    DOE Patents [OSTI]

    Zhang, Shukui (Yorktown, VA); Michelle D. Shinn (Newport News, VA)

    2005-09-13T23:59:59.000Z

    A single lens laser beam shaper for converting laser beams from any spatial profile to a flat-top or uniform spatial profile. The laser beam shaper includes a lens having two aspheric surfaces. The beam shaper significantly simplifies the overall structure in comparison with conventional 2-element systems and therefore provides great ease in alignment and reduction of cost.

  4. Geothermal Life Cycle Calculator

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sullivan, John

    This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

  5. Geothermal Life Cycle Calculator

    SciTech Connect (OSTI)

    Sullivan, John

    2014-03-11T23:59:59.000Z

    This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

  6. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, Henry W. (Somerset, NJ); Hand, Jr, Samuel W. (Hopewell Township, Mercer County, NJ); Ksayian, Haig (Titusville, NJ)

    1986-01-01T23:59:59.000Z

    For use in a tokamak fusion reactor having a midplane magnetic coil on the inner wall of an evacuated toriodal chamber within which a neutral beam heated, fusing plasma is magnetically confined, a neutral beam armor shield and plasma limiter is provided on the inner wall of the toroidal chamber to shield the midplane coil from neutral beam shine-thru and plasma deposition. The armor shield/plasma limiter forms a semicircular enclosure around the midplane coil with the outer surface of the armor shield/plasma limiter shaped to match, as closely as practical, the inner limiting magnetic flux surface of the toroidally confined, indented, bean-shaped plasma. The armor shield/plasma limiter includes a plurality of semicircular graphite plates each having a pair of coupled upper and lower sections with each plate positioned in intimate contact with an adjacent plate on each side thereof so as to form a closed, planar structure around the entire outer periphery of the circular midplane coil. The upper and lower plate sections are adapted for coupling to heat sensing thermocouples and to a circulating water conduit system for cooling the armor shield/plasma limiter.The inner center portion of each graphite plate is adapted to receive and enclose a section of a circular diagnostic magnetic flux loop so as to minimize the power from the plasma confinement chamber incident upon the flux loop.

  7. Etalon-induced Baseline Drift And Correction In Atom Flux Sensors Based On Atomic Absorption Spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20T23:59:59.000Z

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific, real-time flux sensing and control. The ultimate sensitivity and performance of the sensors are strongly affected by the long-term and short term baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability which has not been previously considered or corrected by existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5%, which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  8. The effect of head-on beam-beam compensation on the stochastic boundaries and particle diffusion in RHIC.

    SciTech Connect (OSTI)

    Abreu,N.; Beebe-Wang, J.; FischW; Luo, Y.; Robert-Demolaize, G.

    2008-06-23T23:59:59.000Z

    To compensate the effects from the head-on beam-beam interactions in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), an electron lens (elens) is proposed to collide head-on with the proton beam. We used an extended version of SixTrack for multiparticle beam-beam simulation in order to study the effect of the e-lens on the stochastic boundary and also on diffusion. The stochastic boundary was analyzed using Lyapunov exponents and the diffusion was characterized as the increase in the rms spread of the action. For both studies the simulations were performed with and without the e-lens and with full and partial compensation. Using the simulated values of the diffusion an attempt to calculate the emittance growth rate is presented.

  9. Beam Fields and Energy Dissipation Inside the the BE Beam Pipe of the Super-B Detector

    SciTech Connect (OSTI)

    Novokhatski, Alexander; /SLAC; Sullivan, Michael; /SLAC; ,

    2010-09-10T23:59:59.000Z

    We study the bunch field diffusion and energy dissipation in the beam pipe of the Super-B detector, which consists of two coaxial Be thin pipes (half a millimeter). Cooling water will run between these two pipes. Gold and nickel will be sputtered (several microns) onto the beryllium pipe at different sides. The Maxwell equations for the beam fields in these thin layers are solved numerically for the case of infinite pipes. We also calculate the amplitude of the electromagnetic fields outside the beam pipe, which may be noticeable as the beam current can reach 4 A in each beam. Results of simulations are used for the design of this central part of the Super-B detector.

  10. Carbon Footprint Calculator

    Broader source: Energy.gov [DOE]

    This calculator estimates the amount of carbon emissions you and members of your household are responsible for. It does not include emissions associated with your work or getting to work if you commute by public transportation. It was developed by IEEE Spectrum magazine.

  11. PROPOSED RESIDENTIAL ALTERNATIVE CALCULATION

    E-Print Network [OSTI]

    PROPOSED RESIDENTIAL ALTERNATIVE CALCULATION MANUAL (ACM) APPROVAL METHOD for the 2013 2012 CEC400201200715DAY #12;201308 Residential ACM Approval Manual 2-2 1. Overview Minimum Modeling Capabilities 1. Overview This Manual explains the requirements for approval of residential Alternative

  12. Plutonium 239 Equivalency Calculations

    SciTech Connect (OSTI)

    Wen, J

    2011-05-31T23:59:59.000Z

    This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.

  13. A two-dimensional, semi-analytic expansion method for nodal calculations

    SciTech Connect (OSTI)

    Palmtag, S.P. [Univ. of Missouri, Rolla, MO (United States). Dept. of Nuclear Engineering

    1995-08-01T23:59:59.000Z

    Most modern nodal methods used today are based upon the transverse integration procedure in which the multi-dimensional flux shape is integrated over the transverse directions in order to produce a set of coupled one-dimensional flux shapes. The one-dimensional flux shapes are then solved either analytically or by representing the flux shape by a finite polynomial expansion. While these methods have been verified for most light-water reactor applications, they have been found to have difficulty predicting the large thermal flux gradients near the interfaces of highly-enriched MOX fuel assemblies. A new method is presented here in which the neutron flux is represented by a non-seperable, two-dimensional, semi-analytic flux expansion. The main features of this method are (1) the leakage terms from the node are modeled explicitly and therefore, the transverse integration procedure is not used, (2) the corner point flux values for each node are directly edited from the solution method, and a corner-point interpolation is not needed in the flux reconstruction, (3) the thermal flux expansion contains hyperbolic terms representing analytic solutions to the thermal flux diffusion equation, and (4) the thermal flux expansion contains a thermal to fast flux ratio term which reduces the number of polynomial expansion functions needed to represent the thermal flux. This new nodal method has been incorporated into the computer code COLOR2G and has been used to solve a two-dimensional, two-group colorset problem containing uranium and highly-enriched MOX fuel assemblies. The results from this calculation are compared to the results found using a code based on the traditional transverse integration procedure.

  14. Modeling of the recycling particle flux and electron particle transport in the DIII-D tokamak

    SciTech Connect (OSTI)

    Baker, D.R.; Jackson, G.L. [General Atomics, San Diego, CA (United States); Maingi, R. [Oak Ridge Associated Universities, Inc., TN (United States); Owen, L.W. [Oak Ridge National Lab., TN (United States); Porter, G.D. [Lawrence Livermore National Lab., CA (United States)

    1996-10-01T23:59:59.000Z

    One of the most difficult aspects of performing an equilibrium particle transport analysis in a diverted tokamak is the determination of the particle flux which enters the plasma after recycling from the divertor plasma, the divertor target plates or the vessel wall. An approach which has been utilized in the past is to model the edge, scrape-off layer (SOL), and divertor plasma to match measured plasma parameters and then use a neutral transport code to obtain an edge recycling flux while trying to match the measured divertor D(x emissivity. Previous simulations were constrained by electron density (n{sub e}) and temperature (T{sub e}), ion temperature (T{sub i}) data at the outer midplane, divertor heat flux from infrared television cameras, and n{sub e}, T{sub e} and particle flux at the target from fixed Langmuir probes, along with the divertor D{sub {alpha}} emissivity. In this paper, we present results of core fueling calculations from the 2-D modeling for ELM-free discharges, constrained by data from the new divertor diagnostics. In addition, we present a simple technique for estimating the recycling flux just after the L-H transition and demonstrate how this technique is supported by the detailed modeling. We will show the effect which inaccuracies in the recycling flux have on the calculated particle flux in the plasma core. For some specific density profiles, it is possible to separate the convective flux from the conductive flux. The diffusion coefficients obtained show a sharp decrease near a normalized radius of 0.9 indicating the presence of a transport barrier.

  15. Magnetic topology of coronal mass ejections based on ISEE-3 observations of bidirectional electron fluxes at 1 AU

    SciTech Connect (OSTI)

    Phillips, J.L.; Gosling, J.T.; McComas, D.J.; Bame, S.J.; Feldman, W.C.

    1991-01-01T23:59:59.000Z

    The solar wind electron heat flux is carried primarily by superthermal halo'' electrons with energies at 1 AU of {approximately}80 eV and greater. These halo electrons typically are beamed antisunward along the IMF, indicating effective magnetic connection to the Sun only in one direction. However, ISEE-3 electron observations at 1 AU show that counterstreaming halo beams, suggesting closed magnetic structures, prevail within CMEs. These structures might be magnetic tongues,'' tied to the Sun at both ends, magnetically detached plasmoids, or perhaps complex flux rope structures. We present the results of analysis of ISEE-3 electron observations within 39 CMEs. Parameters analyzed include: the asymmetry between the counterstreaming beams, control by the IMF orientation, and the variation of the electron distributions as a particular CME convects past the spacecraft. We find that some CMEs contain nearly symmetric electron beams, while others are strongly asymmetric, and that beam propagating most nearly antisunward is generally dominant. The more nearly radial the IMF the greater is the symmetry between outward and inward beams. Trends observed as CMEs propagate past the spacecraft probably result primarily from the compression of the leading edge. We present examples of a previously unreported strahl-on-strahl'' distribution, suggesting continued magnetic connection to the corona, in which a narrow antisunward beam is superimposed on a broader beam. Preliminary results show that such spectra are present in a substantial fraction of the observed CMEs. Taken as a whole, our results appear to favor a tongue or flux rope scenario rather than a detached plasmoid.

  16. ICFA Beam Dynamics Newsletter

    SciTech Connect (OSTI)

    Ben-Zvi I.; Kuczewski A.; Altinbas, Z.; Beavis, D.; Belomestnykh,; Dai, J. et al

    2012-07-01T23:59:59.000Z

    The Collider-Accelerator Department at Brookhaven National Laboratory is building a high-brightness 500 mA capable Energy Recovery Linac (ERL) as one of its main R&D thrusts towards eRHIC, the polarized electron - hadron collider as an upgrade of the operating RHIC facility. The ERL is in final assembly stages, with injection commisioning starting in October 2012. The objective of this ERL is to serve as a platform for R&D into high current ERL, in particular issues of halo generation and control, Higher-Order Mode (HOM) issues, coherent emissions for the beam and high-brightness, high-power beam generation and preservation. The R&D ERL features a superconducting laser-photocathode RF gun with a high quantum efficiency photoccathode served with a load-lock cathode delivery system, a highly damped 5-cell accelerating cavity, a highly flexible single-pass loop and a comprehensive system of beam instrumentation. In this ICFA Beam Dynamics Newsletter article we will describe the ERL in a degree of detail that is not usually found in regular publications. We will discuss the various systems of the ERL, following the electrons from the photocathode to the beam dump, cover the control system, machine protection etc and summarize with the status of the ERL systems.

  17. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test

    SciTech Connect (OSTI)

    Jana, M.R.; Bross, A.; Chung, M.; Greer, S.; Johnstone, C.; Kobilarcik, T.; Koizumi, G.; Leonova, M.; Moretti, A.; Popovic, M.; Schwartz, T.; /Fermilab /IIT, Chicago /PDT, Torino

    2012-05-15T23:59:59.000Z

    Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is {approx} 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.

  18. The COMPASS Setup for Physics with Hadron Beams

    E-Print Network [OSTI]

    Abbon, Ph.; Akhunzyanov, R.; Alexandrov, Yu.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Ciliberti, P.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Cotte, D.; Crespo, M.L.; Curiel, Q.; Dafni, T.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Desforge, D.; Dinkelbach, A.M.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Durand, D.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Finger, M.; M. Finger jr; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Gatignon, L.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giganon, A.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Gregori, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Hoppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Jorg, P.; Joosten, R.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kuchinski, N.; Kuhn, R.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Menon, G.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Moinester, M.A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nunes, Ana Sofia; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesaro, G.; Pesaro, V.; Peshekhonov, D.V.; Pires, C.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Reymond, J-M.; Rocco, E.; Rossiyskaya, N.S.; Rousse, J.Y.; Ryabchikov, D.I.; Rychter, A.; Samartsev, A.; Samoylenko, V.D.; Sandacz, A.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Wolbeek, J. ter; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tskhay, V.; Uhl, S.; Uman, I.; Virius, M.; Wang, L.; Weisrock, T.; Weitzel, Q.; Wilfert, M.; Windmolders, R.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.

    2014-01-01T23:59:59.000Z

    The main characteristics of the COMPASS experimental setup for physics with hadron beams are described. This setup was designed to perform exclusive measurements of processes with several charged and/or neutral particles in the final state. Making use of a large part of the apparatus that was previously built for spin structure studies with a muon beam, it also features a new target system as well as new or upgraded detectors. The hadron setup is able to operate at the high incident hadron flux available at CERN. It is characterised by large angular and momentum coverages, large and nearly flat acceptances, and good two and three-particle mass resolutions. In 2008 and 2009 it was successfully used with positive and negative hadron beams and with liquid hydrogen and solid nuclear targets. This article describes the new and upgraded detectors and auxiliary equipment, outlines the reconstruction procedures used, and summarises the general performance of the setup.

  19. Brachytherapy structural shielding calculations using Monte Carlo generated, monoenergetic data

    SciTech Connect (OSTI)

    Zourari, K.; Peppa, V.; Papagiannis, P., E-mail: ppapagi@phys.uoa.gr [Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 11527 Athens (Greece); Ballester, Facundo [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain)] [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Siebert, Frank-André [Clinic of Radiotherapy, University Hospital of Schleswig-Holstein, Campus Kiel 24105 (Germany)] [Clinic of Radiotherapy, University Hospital of Schleswig-Holstein, Campus Kiel 24105 (Germany)

    2014-04-15T23:59:59.000Z

    Purpose: To provide a method for calculating the transmission of any broad photon beam with a known energy spectrum in the range of 20–1090 keV, through concrete and lead, based on the superposition of corresponding monoenergetic data obtained from Monte Carlo simulation. Methods: MCNP5 was used to calculate broad photon beam transmission data through varying thickness of lead and concrete, for monoenergetic point sources of energy in the range pertinent to brachytherapy (20–1090 keV, in 10 keV intervals). The three parameter empirical model introduced byArcher et al. [“Diagnostic x-ray shielding design based on an empirical model of photon attenuation,” Health Phys. 44, 507–517 (1983)] was used to describe the transmission curve for each of the 216 energy-material combinations. These three parameters, and hence the transmission curve, for any polyenergetic spectrum can then be obtained by superposition along the lines of Kharrati et al. [“Monte Carlo simulation of x-ray buildup factors of lead and its applications in shielding of diagnostic x-ray facilities,” Med. Phys. 34, 1398–1404 (2007)]. A simple program, incorporating a graphical user interface, was developed to facilitate the superposition of monoenergetic data, the graphical and tabular display of broad photon beam transmission curves, and the calculation of material thickness required for a given transmission from these curves. Results: Polyenergetic broad photon beam transmission curves of this work, calculated from the superposition of monoenergetic data, are compared to corresponding results in the literature. A good agreement is observed with results in the literature obtained from Monte Carlo simulations for the photon spectra emitted from bare point sources of various radionuclides. Differences are observed with corresponding results in the literature for x-ray spectra at various tube potentials, mainly due to the different broad beam conditions or x-ray spectra assumed. Conclusions: The data of this work allow for the accurate calculation of structural shielding thickness, taking into account the spectral variation with shield thickness, and broad beam conditions, in a realistic geometry. The simplicity of calculations also obviates the need for the use of crude transmission data estimates such as the half and tenth value layer indices. Although this study was primarily designed for brachytherapy, results might also be useful for radiology and nuclear medicine facility design, provided broad beam conditions apply.

  20. Beam Profile Monitor With Accurate Horizontal And Vertical Beam Profiles

    DOE Patents [OSTI]

    Havener, Charles C [Knoxville, TN; Al-Rejoub, Riad [Oak Ridge, TN

    2005-12-26T23:59:59.000Z

    A widely used scanner device that rotates a single helically shaped wire probe in and out of a particle beam at different beamline positions to give a pair of mutually perpendicular beam profiles is modified by the addition of a second wire probe. As a result, a pair of mutually perpendicular beam profiles is obtained at a first beamline position, and a second pair of mutually perpendicular beam profiles is obtained at a second beamline position. The simple modification not only provides more accurate beam profiles, but also provides a measurement of the beam divergence and quality in a single compact device.

  1. Grazing incidence beam expander

    SciTech Connect (OSTI)

    Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

    1985-01-01T23:59:59.000Z

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  2. Beam characteristics of energy-matched flattening filter free beams

    SciTech Connect (OSTI)

    Paynter, D.; Weston, S. J.; Cosgrove, V. P. [St James Institute of Oncology The Leeds Teaching Hospitals NHS Trust, Medical Physics, Leeds LS9 7TF (United Kingdom)] [St James Institute of Oncology The Leeds Teaching Hospitals NHS Trust, Medical Physics, Leeds LS9 7TF (United Kingdom); Evans, J. A. [LIGHT Institute University of Leeds Leeds LS2 9JT, Division of Medical Physics, Leeds (United Kingdom)] [LIGHT Institute University of Leeds Leeds LS2 9JT, Division of Medical Physics, Leeds (United Kingdom); Thwaites, D. I. [LIGHT Institute University of Leeds Leeds LS2 9JT, Division of Medical Physics, Leeds, United Kingdom and Institute of Medical Physics, School of Physics, University of Sydney (Australia)] [LIGHT Institute University of Leeds Leeds LS2 9JT, Division of Medical Physics, Leeds, United Kingdom and Institute of Medical Physics, School of Physics, University of Sydney (Australia)

    2014-05-15T23:59:59.000Z

    Purpose: Flattening filter free (FFF) linear accelerators can increase treatment efficiency and plan quality. There are multiple methods of defining a FFF beam. The Elekta control system supports tuning of the delivered FFF beam energy to enable matching of the percentage depth-dose (PDD) of the flattened beam at 10 cm depth. This is compared to FFF beams where the linac control parameters are identical to those for the flattened beam. All beams were delivered on an Elekta Synergy accelerator with an Agility multi-leaf collimator installed and compared to the standard, flattened beam. The aim of this study is to compare “matched” FFF beams to both “unmatched” FFF beams and flattened beams to determine the benefits of matching beams. Methods: For the three modes of operation 6 MV flattened, 6 MV matched FFF, 6 MV unmatched FFF, 10 MV flattened, 10 MV matched FFF, and 10 MV unmatched FFF beam profiles were obtained using a plotting tank and were measured in steps of 0.1 mm in the penumbral region. Beam penumbra was defined as the distance between the 80% and 20% of the normalized dose when the inflection points of the unflattened and flattened profiles were normalized with the central axis dose of the flattened field set as 100%. PDD data was obtained at field sizes ranging from 3 cm × 3 cm to 40?cm × 40 cm. Radiation protection measurements were additionally performed to determine the head leakage and environmental monitoring through the maze and primary barriers. Results: No significant change is made to the beam penumbra for FFF beams with and without PDD matching, the maximum change in penumbra for a 10 cm × 10 cm field was within the experimental error of the study. The changes in the profile shape with increasing field size are most significant for the matched FFF beam, and both FFF beams showed less profile shape variation with increasing depth when compared to flattened beams, due to consistency in beam energy spectra across the radiation field. The PDDs of the FFF beams showed less variation with field size, the d{sub max} value was deeper for the matched FFF beam than the FFF beam and deeper than the flattened beam for field sizes greater than 5 cm × 5 cm. The head leakage when using the machine in FFF mode is less than half that for a flattened beam, but comparable for both FFF modes. The radiation protection dose-rate measurements show an increase of instantaneous dose-rates when operating the machines in FFF mode but that increase is less than the ratio of MU/min produced by the machine. Conclusions: The matching of a FFF beam to a flattened beam at a depth of 10 cm in water by increasing the FFF beam energy does not reduce any of the reported benefits of FFF beams. Conversely, there are a number of potential benefits resulting from matching the FFF beam; the depth of maximum dose is deeper, the out of field dose is potentially reduced, and the beam quality and penetration more closely resembles the flattened beams currently used in clinical practice, making dose distributions in water more alike. Highlighted in this work is the fact that some conventional specifications and methods for measurement of beam parameters such as penumbra are not relevant and further work is required to address this situation with respect to “matched” FFF beams and to determine methods of measurement that are not reliant on an associated flattened beam.

  3. Monte Carlo based beam model using a photon MLC for modulated electron radiotherapy

    SciTech Connect (OSTI)

    Henzen, D., E-mail: henzen@ams.unibe.ch; Manser, P.; Frei, D.; Volken, W.; Born, E. J.; Vetterli, D.; Chatelain, C.; Fix, M. K. [Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, CH-3010 Berne (Switzerland)] [Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, CH-3010 Berne (Switzerland); Neuenschwander, H. [Clinic for Radiation-Oncology, Lindenhofspital Bern, CH-3012 Berne (Switzerland)] [Clinic for Radiation-Oncology, Lindenhofspital Bern, CH-3012 Berne (Switzerland); Stampanoni, M. F. M. [Institute for Biomedical Engineering, ETH Zürich and Paul Scherrer Institut, CH-5234 Villigen (Switzerland)] [Institute for Biomedical Engineering, ETH Zürich and Paul Scherrer Institut, CH-5234 Villigen (Switzerland)

    2014-02-15T23:59:59.000Z

    Purpose: Modulated electron radiotherapy (MERT) promises sparing of organs at risk for certain tumor sites. Any implementation of MERT treatment planning requires an accurate beam model. The aim of this work is the development of a beam model which reconstructs electron fields shaped using the Millennium photon multileaf collimator (MLC) (Varian Medical Systems, Inc., Palo Alto, CA) for a Varian linear accelerator (linac). Methods: This beam model is divided into an analytical part (two photon and two electron sources) and a Monte Carlo (MC) transport through the MLC. For dose calculation purposes the beam model has been coupled with a macro MC dose calculation algorithm. The commissioning process requires a set of measurements and precalculated MC input. The beam model has been commissioned at a source to surface distance of 70 cm for a Clinac 23EX (Varian Medical Systems, Inc., Palo Alto, CA) and a TrueBeam linac (Varian Medical Systems, Inc., Palo Alto, CA). For validation purposes, measured and calculated depth dose curves and dose profiles are compared for four different MLC shaped electron fields and all available energies. Furthermore, a measured two-dimensional dose distribution for patched segments consisting of three 18 MeV segments, three 12 MeV segments, and a 9 MeV segment is compared with corresponding dose calculations. Finally, measured and calculated two-dimensional dose distributions are compared for a circular segment encompassed with a C-shaped segment. Results: For 15 × 34, 5 × 5, and 2 × 2 cm{sup 2} fields differences between water phantom measurements and calculations using the beam model coupled with the macro MC dose calculation algorithm are generally within 2% of the maximal dose value or 2 mm distance to agreement (DTA) for all electron beam energies. For a more complex MLC pattern, differences between measurements and calculations are generally within 3% of the maximal dose value or 3 mm DTA for all electron beam energies. For the two-dimensional dose comparisons, the differences between calculations and measurements are generally within 2% of the maximal dose value or 2 mm DTA. Conclusions : The results of the dose comparisons suggest that the developed beam model is suitable to accurately reconstruct photon MLC shaped electron beams for a Clinac 23EX and a TrueBeam linac. Hence, in future work the beam model will be utilized to investigate the possibilities of MERT using the photon MLC to shape electron beams.

  4. On solar neutrino fluxes in radiochemical experiments

    E-Print Network [OSTI]

    R. N. Ikhsanov; Yu. N. Gnedin; E. V. Miletsky

    2005-12-08T23:59:59.000Z

    We analyze fluctuations of the solar neutrino flux using data from the Homestake, GALLEX, GNO, SAGE and Super Kamiokande experiments. Spectral analysis and direct quantitative estimations show that the most stable variation of the solar neutrino flux is a quasi-five-year periodicity. The revised values of the mean solar neutrino flux are presented in Table 4. They were used to estimate the observed pp-flux of the solar electron neutrinos near the Earth. We consider two alternative explanations for the origin of a variable component of the solar neutrino deficit.

  5. Fluxing agent for metal cast joining

    DOE Patents [OSTI]

    Gunkel, Ronald W. (Lower Burrell, PA); Podey, Larry L. (Greensburg, PA); Meyer, Thomas N. (Murrysville, PA)

    2002-11-05T23:59:59.000Z

    A method of joining an aluminum cast member to an aluminum component. The method includes the steps of coating a surface of an aluminum component with flux comprising cesium fluoride, placing the flux coated component in a mold, filling the mold with molten aluminum alloy, and allowing the molten aluminum alloy to solidify thereby joining a cast member to the aluminum component. The flux preferably includes aluminum fluoride and alumina. A particularly preferred flux includes about 60 wt. % CsF, about 30 wt. % AlF.sub.3, and about 10 wt. % Al.sub.2 O.sub.3.

  6. Steep Slope Calculator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary900Steep Slope Calculator Estimates Cooling and Heating

  7. PURIFICATION OF IRIDIUM BY ELECTRON BEAM MELTING

    SciTech Connect (OSTI)

    Ohriner, Evan Keith [ORNL

    2008-01-01T23:59:59.000Z

    The purification of iridium metal by electron beam melting has been characterized for 48 impurity elements. Chemical analysis was performed by glow discharge mass spectrographic (GDMS) analysis for all elements except carbon, which was analyzed by combustion. The average levels of individual elemental impurities in the starting powder varied from 37 g/g to 0.02 g/g. The impurity elements Li, Na, Mg, P, S, Cl, K, Ca, Mn, Co, Ni, Cu, Zn, As, Pd, Ag, Cd, Sn, Sb, Te, Ba, Ce, Tl, Pb, and Bi were not detectable following the purification. No significant change in concentration of the elements Ti, V, Zr, Nb, Mo, and Re was found. The elements B, C, Al, Si, Cr, Fe, Ru, Rh, and Pt were partially removed by vaporization during electron beam melting. Langmuir's equation for ideal vaporization into a vacuum was used to calculate for each impurity element the expected ratio of impurity content after melting to that before melting. Equilibrium vapor pressures were calculated using Henry's law, with activity coefficients obtained from published data for the elements Fe, Ti, and Pt. Activity coefficients were estimated from enthalpy data for Al, Si, V, Cr, Mn, Co, Ni, Zr, Nb, Mo, and Hf and an ideal solution model was used for the remaining elements. The melt temperature was determined from measured iridium weight loss. Excellent agreement was found between measured and calculated impurity ratios for all impurity elements. The results are consistent with some localized heating of the melt pool due to rastering of the electron beam, with an average vaporization temperature of 3100 K as compared to a temperature of 2965 K calculated for uniform heating of the melt pool. The results are also consistent with ideal mixing in the melt pool.

  8. Neutron beam characterization at the Neutron Radiography Reactor (NRAD)

    SciTech Connect (OSTI)

    Imel, G.R.; Urbatsch, T.; Pruett, D.P.; Ross, J.R.

    1990-01-01T23:59:59.000Z

    The Neutron Radiography Reactor (NRAD) is a 250-kW TRIGA Reactor operated by Argonne National Laboratory and is located near Idaho Falls, Idaho. The reactor and its facilities regarding radiography are detailed in another paper at this conference; this paper summarizes neutron flux measurements and calculations that have been performed to better understand and potentially improve the neutronics characteristics of the reactor.

  9. Issues concerning high current lower energy electron beams required for ion cooling between EBIS LINAC and booster

    SciTech Connect (OSTI)

    Hershcovitch,A.

    2009-03-01T23:59:59.000Z

    Some issues, regarding a low energy high current electron beam that will be needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, are examined. Options for propagating such an electron beam, as well as the effect of neutralizing background plasma on electron and ion beam parameters are calculated. Computations and some experimental data indicate that none of these issues is a show stopper.

  10. Comparison of the high temperature heat flux sensor to traditional heat flux gages under high heat flux conditions.

    SciTech Connect (OSTI)

    Blanchat, Thomas K.; Hanks, Charles R.

    2013-04-01T23:59:59.000Z

    Four types of heat flux gages (Gardon, Schmidt-Boelter, Directional Flame Temperature, and High Temperature Heat Flux Sensor) were assessed and compared under flux conditions ranging between 100-1000 kW/m2, such as those seen in hydrocarbon fire or propellant fire conditions. Short duration step and pulse boundary conditions were imposed using a six-panel cylindrical array of high-temperature tungsten lamps. Overall, agreement between all gages was acceptable for the pulse tests and also for the step tests. However, repeated tests with the HTHFS with relatively long durations at temperatures approaching 1000%C2%B0C showed a substantial decrease (10-25%) in heat flux subsequent to the initial test, likely due to the mounting technique. New HTHFS gages have been ordered to allow additional tests to determine the cause of the flux reduction.

  11. Observation of Coherent Beam-beam Effects in the LHC

    E-Print Network [OSTI]

    Buffat, X; Giachino, R; Herr, W; Papotti, G; Pieloni, T; Calaga, R; White, S M

    2011-01-01T23:59:59.000Z

    Early collisions in the LHC with a very limited number of bunches with high intensities indicated the presence of coherent beam-beam driven oscillations. Here we discuss the experimental results and compare with the expectations.

  12. Electron beam dynamics for the ISIS bremsstrahlung beam generation system

    E-Print Network [OSTI]

    Block, Robert E. (Robert Edward)

    2011-01-01T23:59:59.000Z

    An electron beam transport system was designed for use in the Bremsstrahlung Beam Generation System of the Integrated Stand-off Inspection System (ISIS). The purpose of this electron transport system was to provide for ...

  13. Heavy Oil Upgrading from Electron Beam (E-Beam) Irradiation 

    E-Print Network [OSTI]

    Yang, Daegil

    2011-02-22T23:59:59.000Z

    hydrocarbons. Second, we studied the energy transfer mechanism of E-Beam upgrading to optimize the process. Third, we conducted a preliminary economic analysis based on energy consumption and compared the economics of E-Beam upgrading with conventional...

  14. E × B shear pattern formation by radial propagation of heat flux waves

    SciTech Connect (OSTI)

    Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of); IAS and RIAM, Kyushu University, Fukuoka (Japan); Diamond, P. H. [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of) [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of); CASS and CMTFO, University of California, San Diego, California 92093 (United States); Dif-Pradalier, G. [CEA, IRFM, Paul-lez-Durance Cedex (France)] [CEA, IRFM, Paul-lez-Durance Cedex (France); Gürcan, Ö. D. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Palaiseau (France)] [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Palaiseau (France)

    2014-05-15T23:59:59.000Z

    A novel theory to describe the formation of E×B flow patterns by radially propagating heat flux waves is presented. A model for heat avalanche dynamics is extended to include a finite delay time between the instantaneous heat flux and the mean flux, based on an analogy between heat avalanche dynamics and traffic flow dynamics. The response time introduced here is an analogue of the drivers' response time in traffic dynamics. The microscopic foundation for the time delay is the time for mixing of the phase space density. The inclusion of the finite response time changes the model equation for avalanche dynamics from Burgers equation to a nonlinear telegraph equation. Based on the telegraph equation, the formation of heat flux jams is predicted. The growth rate and typical interval of jams are calculated. The connection of the jam interval to the typical step size of the E×B staircase is discussed.

  15. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-01-02T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for portable high-precision quantum sensors.

  16. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Rudolph, Jan; Grzeschik, Christoph; Sternke, Tammo; Grote, Alexander; Popp, Manuel; Becker, Dennis; Müntinga, Hauke; Ahlers, Holger; Peters, Achim; Lämmerzahl, Claus; Sengstock, Klaus; Gaaloul, Naceur; Ertmer, Wolfgang; Rasel, Ernst M

    2015-01-01T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of...

  17. Colliding beams of light

    E-Print Network [OSTI]

    B. V. Ivanov

    2002-12-28T23:59:59.000Z

    The stationary gravitational field of two identical counter-moving beams of pure radiation is found in full generality. The solution depends on an arbitrary function and a parameter which sets the scale of the energy density. Some of its properties are studied. Previous particular solutions are derived as subcases.

  18. Ion-beam technologies

    SciTech Connect (OSTI)

    Fenske, G.R. [Argonne National Lab., IL (United States)

    1993-01-01T23:59:59.000Z

    This compilation of figures and diagrams reviews processes for depositing diamond/diamond-like carbon films. Processes addressed are chemical vapor deposition (HFCVD, PACVD, etc.), plasma vapor deposition (plasma sputtering, ion beam sputtering, evaporation, etc.), low-energy ion implantation, and hybrid processes (biased sputtering, IBAD, biased HFCVD, etc.). The tribological performance of coatings produced by different means is discussed.

  19. Multi-transmission-line-beam interactive system

    SciTech Connect (OSTI)

    Figotin, Alexander; Reyes, Guillermo [Department of Mathematics, University of California at Irvine, Irvine, California 92697-3875 (United States)] [Department of Mathematics, University of California at Irvine, Irvine, California 92697-3875 (United States)

    2013-11-15T23:59:59.000Z

    We construct here a Lagrangian field formulation for a system consisting of an electron beam interacting with a slow-wave structure modeled by a possibly non-uniform multiple transmission line (MTL). In the case of a single line we recover the linear model of a traveling wave tube due to J. R. Pierce. Since a properly chosen MTL can approximate a real waveguide structure with any desired accuracy, the proposed model can be used in particular for design optimization. Furthermore, the Lagrangian formulation provides: (i) a clear identification of the mathematical source of amplification, (ii) exact expressions for the conserved energy and its flux distributions obtained from the Noether theorem. In the case of uniform MTLs we carry out an exhaustive analysis of eigenmodes and find sharp conditions on the parameters of the system to provide for amplifying regimes.

  20. Data system for automatic flux mapping applications

    SciTech Connect (OSTI)

    Couch, R.D.; Kasinoff, A.M.; Neuner, J.A.; Oates, R.M.

    1980-12-16T23:59:59.000Z

    In an automatic flux mapping system utilizing a microprocessor for control and data information processing, signals from the incore detectors providing the flux mapping operation are converted to a frequency link and are made available to the microprocessor via a programmable timer thus minimizing the participation of the microprocessor so that the microprocessor can be made more available to satisfy other tasks.

  1. Evaporative cooling of a guided rubidium atomic beam T. Lahaye, Z. Wang, G. Reinaudi, S. P. Rath, J. Dalibard, and D. Gury-Odelin

    E-Print Network [OSTI]

    Dalibard, Jean

    Evaporative cooling of a guided rubidium atomic beam T. Lahaye, Z. Wang, G. Reinaudi, S. P. Rath, J Received 30 May 2005; published 19 September 2005 We report on our recent progress in the manipulation and cooling of a magnetically guided, high-flux beam of 87 Rb atoms. Typically, 7 109 atoms per second

  2. Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling; Is Single Pass Cooling Possible?

    SciTech Connect (OSTI)

    Hershcovitch,A.

    2008-04-01T23:59:59.000Z

    Electron beam cooling is examined as an option to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster. Electron beam parameters are based on experimental data (obtained at BNL) of electron beams extracted from a plasma cathode. Preliminary calculations indicate that single pass cooling is feasible; momentum spread can be reduced by more than an order of magnitude in less than one meter.

  3. Computer simulation of the processes at electron beam technologies

    SciTech Connect (OSTI)

    Mladenov, G.M.; Vutova, K.; Sabchevsky, S. [Institute of Electronics, Sofia (Bulgaria)

    1994-12-31T23:59:59.000Z

    The computer software packages developed in Bulgaria are among our important research results concerning EB melting and refining. (i) In the field of the gun and the beam improvement optimisation: A new approach, based on beam phase analysis, has been proposed and applied in a computer software package. The computer simulation of beam formation and transport permit to optimize technology electron guns and predict some features of the processes. A investigation of the ion compensation of the electron space charge in the beam at different technology conditions is in progress. (ii) In the electron beam refining technology. The kinetics of the impurities evaporation and refining of the low density contaminants at the drip or cold hearth melting has been investigated. Computer calculation of the component concentration changes during refinement had been developed. Analysis of main processes of the impurity transport can be studied. (iii) In the field of beam heating of the materials: Computer simulation of the heat transport is done. Deep of the melted pool, thermal distribution in the casted ingot as the temperature loading of the equipment parts are possible to be calculated.

  4. The Cooling of Particle Beams

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    67, 15. Hangst, J "Laser Cooling of a Stored Ion Beam - ATheorem an.d Phase Space Cooling", Proceedings of theWorkshop on Beam Cooling and Related Topics, Montreaux, CERN

  5. Hadron beams session-summary

    SciTech Connect (OSTI)

    Terwilliger, K.M. (University of Michigan, Ann Arbor, MI 48109-1120, USA (US))

    1989-05-05T23:59:59.000Z

    The status of presently operating polarized beams at Fermilab, the AGS, and KEK is discussed. Other schemes such as Siberian Snakes and self-polarization of a beam in situ are briefly analyzed.(AIP)

  6. Laser beam pulse formatting method

    DOE Patents [OSTI]

    Daly, T.P.; Moses, E.I.; Patterson, R.W.; Sawicki, R.H.

    1994-08-09T23:59:59.000Z

    A method for formatting a laser beam pulse using one or more delay loops is disclosed. The delay loops have a partially reflective beam splitter and a plurality of highly reflective mirrors arranged such that the laser beam pulse enters into the delay loop through the beam splitter and circulates therein along a delay loop length defined by the mirrors. As the laser beam pulse circulates within the delay loop a portion thereof is emitted upon each completed circuit when the laser beam pulse strikes the beam splitter. The laser beam pulse is thereby formatted into a plurality of sub-pulses. The delay loops are used in combination to produce complex waveforms by combining the sub-pulses using additive waveform synthesis. 8 figs.

  7. Be7(p,gamma)B8 and the high-energy solar neutrino flux

    E-Print Network [OSTI]

    Attila Csoto

    1997-04-23T23:59:59.000Z

    The importance of the Be7(p,gamma)B8 reaction in predicting the high-energy solar neutrino flux is discussed. I present a microscopic eight-body model and a potential model for the calculation of the Be7(p,gamma)B8 cross section.

  8. Comparison of different global information sources used in surface radiative flux calculation

    E-Print Network [OSTI]

    ), the Laboratoire de Me´te´orologie Dynamique, NOAA/NASA Pathfinder Advanced Very High Resolution Radiometer project Spectroradiometer product, the NASA Global Energy and Water Cycle Experiment Surface Radiation Budget project surface albedos in the near-infrared remain poorly constrained (highly uncertain), they do not cause too

  9. Understanding Supernova Neutrino Physics using Low-Energy Beta-Beams

    E-Print Network [OSTI]

    N. Jachowicz; G. C. McLaughlin

    2005-11-24T23:59:59.000Z

    We show that fitting linear combinations of low-energy beta-beam spectra to supernova-neutrino energy-distributions reconstructs the response of a nuclear target to a supernova flux in a very accurate way. This allows one to make direct predictions about the supernova-neutrino signal in a terrestrial neutrino detector.

  10. BETA BEAMS: AN ACCELERATOR BASED FACILITY TO EXPLORE NEUTRINO OSCILLATION PHYSICS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    them decay in a race-track shaped stor- age ring. EURO Beta Beams are based on CERNs infras- tructure to get high neutrino flux at a gamma boost of 100. INTRODUCTION Production of (anti-)neutrinos from beta facility, using the isotope pair 6 He/18 Ne and detector in the Fr´ejus tunnel (France) has been studied

  11. High flux isotope reactor cold source preconceptual design study report

    SciTech Connect (OSTI)

    Selby, D.L.; Bucholz, J.A.; Burnette, S.E. [and others

    1995-12-01T23:59:59.000Z

    In February 1995, the deputy director of Oak Ridge National Laboratory (ORNL) formed a group to examine the need for upgrades to the High Flux Isotope Reactor (HFIR) system in light of the cancellation of the Advanced Neutron Source Project. One of the major findings of this study was that there was an immediate need for the installation of a cold neutron source facility in the HFIR complex. The anticipated cold source will consist of a cryogenic LH{sub 2} moderator plug, a cryogenic pump system, a refrigerator that uses helium gas as a refrigerant, a heat exchanger to interface the refrigerant with the hydrogen loop, liquid hydrogen transfer lines, a gas handling system that includes vacuum lines, and an instrumentation and control system to provide constant system status monitoring and to maintain system stability. The scope of this project includes the development, design, safety analysis, procurement/fabrication, testing, and installation of all of the components necessary to produce a working cold source within an existing HFIR beam tube. This project will also include those activities necessary to transport the cold neutron beam to the front face of the present HFIR beam room. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and research and development (R and D), (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the preconceptual phase and establishes the concept feasibility. The information presented includes the project scope, the preliminary design requirements, the preliminary cost and schedule, the preliminary performance data, and an outline of the various plans for completing the project.

  12. Measuring the Magnetic Flux Density in the CMS Steel Yoke

    E-Print Network [OSTI]

    V. I. Klyukhin; N. Amapane; A. Ball; B. Curé; A. Gaddi; H. Gerwig; A. Hervé; M. Mulders; R. Loveless

    2012-12-06T23:59:59.000Z

    The Compact Muon Solenoid (CMS) is a general purpose detector, designed to run at the highest luminosity at the CERN Large Hadron Collider (LHC). Its distinctive features include a 4 T superconducting solenoid with 6-m-diameter by 12.5-m-length free bore, enclosed inside a 10000-ton return yoke made of construction steel. The return yoke consists of five dodecagonal three-layered barrel wheels and four end-cap disks at each end comprised of steel blocks up to 620 mm thick, which serve as the absorber plates of the muon detection system. Accurate characterization of the magnetic field everywhere in the CMS detector is required. To measure the field in and around the steel, a system of 22 flux-loops and 82 3-D Hall sensors is installed on the return yoke blocks. Fast discharges of the solenoid (190 s time-constant) made during the CMS magnet surface commissioning test at the solenoid central fields of 2.64, 3.16, 3.68 and 4.01 T were used to induce voltages in the flux-loops. The voltages are measured on-line and integrated off-line to obtain the magnetic flux in the steel yoke close to the muon chambers at full excitations of the solenoid. The 3-D Hall sensors installed on the steel-air interfaces give supplementary information on the components of magnetic field and permit to estimate the remanent field in steel to be added to the magnetic flux density obtained by the voltages integration. A TOSCA 3-D model of the CMS magnet is developed to describe the magnetic field everywhere outside the tracking volume measured with the field-mapping machine. The results of the measurements and calculations are presented, compared and discussed.

  13. Ion beam characteristics of the controlatron/zetatron family of the gas filled neutron tubes

    SciTech Connect (OSTI)

    Berg, R.S.; Shope, L.A.; O'Neal, M.L.; Boers, J.E.; Bickes, R.W. Jr.

    1981-03-01T23:59:59.000Z

    A gas filled tube used to produce a neutron flux with the D(T,He/sup 4/)n reaction is described. Deuterium and tritium ions generated in a reflex discharge are extracted and accelerated to 100 keV by means of an accelerator electrode onto a deutero-tritide target electrode. The electrodes are designed to focus the ion beam onto the target. Total tube currents consisting of extracted ions, unsuppressed secondary electrons, and ions generated by interactions with the background gas are typically 100 mA. The characteristics of the extracted ion beam are discussed. Accelerating voltages greater than 50 kV are required to focus the beam through the accelerator aperture for configurations that give beams with the proper energy density onto the target. The perveance of the beam is discussed. Maximum perveance values are 2 to 20 nanopervs. Tube focusing and neutron production characteristics are described.

  14. Four-Button BPM Coefficients in Cylindrical and Elliptic Beam Chambers February 17, 1999

    E-Print Network [OSTI]

    Kemner, Ken

    Four-Button BPM Coefficients in Cylindrical and Elliptic Beam Chambers S. H. Kim February 17, 1999 Beam position monitor (BPM) coefficients are calculated from induced charges on four-button BPMs ring is different from an exact elliptic geometry, numerical values of the BPM coefficients

  15. New solar opacities, abundances, helioseismology, and neutrino fluxes

    E-Print Network [OSTI]

    John N. Bahcall; Aldo M. Serenelli; Sarbani Basu

    2005-01-19T23:59:59.000Z

    We construct solar models with the newly calculated radiative opacities from the Opacity Project (OP) and recently determined (lower) heavy element abundances. We compare results from the new models with predictions of a series of models that use OPAL radiative opacities, older determinations of the surface heavy element abundances, and refinements of nuclear reaction rates. For all the variations we consider, solar models that are constructed with the newer and lower heavy element abundances advocated by Asplund et al. (2005) disagree by much more than the estimated measuring errors with helioseismological determinations of the depth of the solar convective zone, the surface helium composition, the internal sound speeds, and the density profile. Using the new OP radiative opacities, the ratio of the 8B neutrino flux calculated with the older and larger heavy element abundances (or with the newer and lower heavy element abundances) to the total neutrino flux measured by the Sudbury Neutrino Observatory is 1.09 (0.87) with a 9% experimental uncertainty and a 16% theoretical uncertainty, 1 sigma errors.

  16. Energy spectrum control for modulated proton beams

    SciTech Connect (OSTI)

    Hsi, Wen C.; Moyers, Michael F.; Nichiporov, Dmitri; Anferov, Vladimir; Wolanski, Mark; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E.; Schreuder, Andries N. [Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); Proton Therapy, Inc., Colton, California 92324 (United States); Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States) and Westdeutsches Protonentherapiezentrum, Universitaetsklinikum, Hufelandstrasse 55, 45147 Essen (Germany); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States) and ProCure Treatment Centers, Inc., Bloomington, Indiana 47404 (United States)

    2009-06-15T23:59:59.000Z

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to {+-}21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than {+-}3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies.

  17. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    SciTech Connect (OSTI)

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland)] [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico)] [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland) [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15T23:59:59.000Z

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup ?} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  18. Summary of working group g: beam material interaction

    SciTech Connect (OSTI)

    Kiselev, D.; /PSI, Villigen; Mokhov, N.V.; /Fermilab; Schmidt, R.; /CERN

    2010-11-01T23:59:59.000Z

    For the first time, the workshop on High-Intensity and High-Brightness Hadron Beams (HB2010), held at Morschach, Switzerland and organized by the Paul Scherrer Institute, included a Working group dealing with the interaction between beam and material. Due to the high power beams of existing and future facilities, this topic is already of great relevance for such machines and is expected to become even more important in the future. While more specialized workshops related to topics of radiation damage, activation or thermo-mechanical calculations, already exist, HB2010 provided the occasion to discuss the interplay of these topics, focusing on components like targets, beam dumps and collimators, whose reliability are crucial for a user facility. In addition, a broader community of people working on a variety of issues related to the operation of accelerators could be informed and their interest sparked.

  19. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-12T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 Ap to 0.6 .Ap in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  20. Beam-driven acceleration in ultra-dense plasma media

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  1. Measurements of Beam Ion Loss from the Compact Helical System

    SciTech Connect (OSTI)

    D. S. Darrow, M. Isobe, Takashi Kondo, M. Sasao, and the CHS Group National Institute for Fusion Science, Toki, Gifu, Japan

    2010-02-03T23:59:59.000Z

    Beam ion loss from the Compact Helical System (CHS) has been measured with a scintillator-type probe. The total loss to the probe, and the pitch angle and gyroradius distributions of that loss, have been measured as various plasma parameters were scanned. Three classes of beam ion loss were observed at the probe position: passing ions with pitch angles within 10o of those of transition orbits, ions on transition orbits, and ions on trapped orbits, typically 15o or more from transition orbits. Some orbit calculations in this geometry have been performed in order to understand the characteristics of the loss. Simulation of the detector signal based upon the following of orbits from realistic beam deposition profiles is not able to reproduce the pitch angle distribution of the losses measured. Consequently it is inferred that internal plasma processes, whether magnetohydrodynamic modes, radial electric fields, or plasma turbulence, move previously confined beam ions to transition orbits, resulting in their loss.

  2. Beam-driven acceleration in ultra-dense plasma media

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shin, Young-Min

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r)more »from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.« less

  3. LHC Beam Loss Measurements and Quench Level Abort Threshold Accuracy

    E-Print Network [OSTI]

    Dehning, B; Sapinski, M

    2010-01-01T23:59:59.000Z

    The LHC beam loss measurement system is designed to trigger the beam abort in case the magnet coil transition level from the superconducting to normal conducting sate is approached. The predicted heat deposition in the superconducting coils of the magnets has been determined by particle shower simulation codes, while for transient losses the enthalpy has been calculated. The results have been combined to determine the abort thresholds. Transient loss measurements of the energy depositions of lost protons with injected beams in the LHC are used to determine the accuracy of the beam abort threshold settings. The simulation predictions are reviewed and compared with the measurement results. The relative difference between measurements and simulation are between 30 to 50 %.

  4. Contribution of GRB Emission to the GeV Extragalactic Diffuse Gamma-Ray Flux

    E-Print Network [OSTI]

    S. Casanova; B. L. Dingus; Bing Zhang

    2006-11-03T23:59:59.000Z

    TeV gamma rays emitted by GRBs are converted into electron-positron pairs via interactions with the extragalactic infrared radiation fields. In turn the pairs produced, whose trajectories are randomized by magnetic fields, will inverse Compton scatter off the cosmic microwave background photons. The beamed TeV gamma ray flux from GRBs is thus transformed into a GeV isotropic gamma ray flux, which contributes to the total extragalactic gamma-ray background emission. Assuming a model for the extragalactic radiation fields, for the GRB redshift distribution and for the GRB luminosity function, we evaluate the contribution of the GRB prompt and scattered emissions to the measured extragalactic gamma-ray flux. To estimate this contribution we optimistically require that the energy flux at TeV energies is about 10 times stronger than the energy flux at MeV energies. The resulting gamma-ray diffuse background is only a small fraction of what is observed, allowing blazars and other sources to give the dominant contribution.

  5. Metallic beam development for the Facility for Rare Isotope Beam

    SciTech Connect (OSTI)

    Machicoane, Guillaume, E-mail: machicoa@nscl.msu.edu; Cole, Dallas; Leitner, Daniela; Neben, Derek; Tobos, Larry [Facility for Rare Isotope Beam, Michigan State University, East Lansing, Michigan 48824 (United States)] [Facility for Rare Isotope Beam, Michigan State University, East Lansing, Michigan 48824 (United States)

    2014-02-15T23:59:59.000Z

    The Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU) will accelerate a primary ion beam to energies beyond 200 MeV/u using a superconducting RF linac and will reach a maximum beam power of 400 kW on the fragmentation target. The beam intensity needed from the ECR ion source is expected to be between 0.4 and 0.5 emA for most medium mass to heavy mass elements. Adding to the challenge of reaching the required intensity, an expanded list of primary beams of interest has been established based on the production rate and the number of isotope beams that could be produced with FRIB. We report here on the development done for some of the beam in the list including mercury (natural), molybdenum ({sup 98}Mo), and selenium ({sup 82}Ser)

  6. DESIGN OF BEAM-EXTRACTION SEPTUM MAGNET FOR THE SNS.

    SciTech Connect (OSTI)

    TSOUPAS,N.; LEE,Y.Y.; RANK,J.; TUOZZOLO,J.

    2001-06-18T23:59:59.000Z

    The beam-extraction process from the SNS accumulator ring [1,2] requires a Lambertson septum magnet. In this paper we discuss the geometrical and magnetic field requirements of the magnet and present results obtained from two and three dimensional magnetic field calculations that shows the field quality in the regions of interest of the septum magnet.

  7. Radiative component and combined heat transfer in the thermal calculation of finned tube banks

    SciTech Connect (OSTI)

    Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering

    1999-01-01T23:59:59.000Z

    For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.

  8. Results of long-range beam-beam studies - scaling with beam separation and intensity

    E-Print Network [OSTI]

    Assmann, R; Buffat, X; Calaga, R; Giachino, R; Herr, W; Metral, E; Papotti, G; Pieloni, T; Roy, G; Trad, G; Kaltchev, D; CERN. Geneva. ATS Department

    2012-01-01T23:59:59.000Z

    We studied possible limitations due to the long-range beam-beam effects in the LHC. With a large number of bunches and collisions in all interaction points, we have reduced the crossing angles to enhance long-range beam-beam effects to evaluate their influence on dynamic aperture and losses. Different beta* and intensities have been used in two dedicated experiments and allow the test of the expected scaling laws.

  9. Calculation of Accurate Hexagonal Discontinuity Factors for PARCS

    SciTech Connect (OSTI)

    Pounders. J., Bandini, B. R. , Xu, Y, and Downar, T. J.

    2007-11-01T23:59:59.000Z

    In this study we derive a methodology for calculating discontinuity factors consistent with the Triangle-based Polynomial Expansion Nodal (TPEN) method implemented in PARCS for hexagonal reactor geometries. The accuracy of coarse-mesh nodal methods is greatly enhanced by permitting flux discontinuities at node boundaries, but the practice of calculating discontinuity factors from infinite-medium (zero-current) single bundle calculations may not be sufficiently accurate for more challenging problems in which there is a large amount of internodal neutron streaming. The authors therefore derive a TPEN-based method for calculating discontinuity factors that are exact with respect to generalized equivalence theory. The method is validated by reproducing the reference solution for a small hexagonal core.

  10. A computer program for HVDC converter station RF noise calculations

    SciTech Connect (OSTI)

    Kasten, D.G.; Caldecott, R.; Sebo, S.A. (Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering); Liu, Y. (Virginia Polytechnic Inst. State Univ., Blacksburg, VA (United States). Bradley Dept. of Electrical Engineering)

    1994-04-01T23:59:59.000Z

    HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

  11. Intense Ion Beam for Warm Dense Matter Physics

    SciTech Connect (OSTI)

    Coleman, Joshua Eugene

    2008-05-23T23:59:59.000Z

    The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam intensity. We present results of beam transport through a solenoid matching section and simultaneous focusing of a singly charged K{sup +} ion bunch at an ion energy of 0.3 MeV. The results include a qualitative comparison of experimental and calculated results after the solenoid matching section, which include time resolved current density, transverse distributions, and phase-space of the beam at different diagnostic planes. Electron cloud and gas measurements in the solenoid lattice and in the vicinity of intercepting diagnostics are also presented. Finally, comparisons of improved experimental and calculated axial focus (> 100 x axial compression, < 2 ns pulses) and higher peak energy deposition on target are also presented. These achievements demonstrate the capabilities for near term target heating experiments to T{sub e} {approx} 0.1 eV and for future ion accelerators to heat targets to T{sub e} > 1 eV.

  12. TRACKING CODE DEVELOPMENT FOR BEAM DYNAMICS OPTIMIZATION

    SciTech Connect (OSTI)

    Yang, L.

    2011-03-28T23:59:59.000Z

    Dynamic aperture (DA) optimization with direct particle tracking is a straight forward approach when the computing power is permitted. It can have various realistic errors included and is more close than theoretical estimations. In this approach, a fast and parallel tracking code could be very helpful. In this presentation, we describe an implementation of storage ring particle tracking code TESLA for beam dynamics optimization. It supports MPI based parallel computing and is robust as DA calculation engine. This code has been used in the NSLS-II dynamics optimizations and obtained promising performance.

  13. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); Galvin, James (2 Commodore #276, Emeryville, CA 94608)

    1987-01-01T23:59:59.000Z

    An ion generating apparatus utilizing a vacuum chamber, a cathode and an anode in the chamber. A source of electrical power produces an arc or discharge between the cathode and anode. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma is directed to an extractor which separates the electrons from the plasma, and accelerates the ions to produce an ion beam.

  14. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, I.G.; Galvin, J.

    1987-12-22T23:59:59.000Z

    An ion generating apparatus utilizing a vacuum chamber, a cathode and an anode in the chamber. A source of electrical power produces an arc or discharge between the cathode and anode. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma is directed to an extractor which separates the electrons from the plasma, and accelerates the ions to produce an ion beam. 10 figs.

  15. Stationary nonlinear Airy beams

    SciTech Connect (OSTI)

    Lotti, A. [Dipartimento di Fisica e Matematica, Universita del'Insubria, Via Valleggio 11, I-22100 Como (Italy); Centre de Physique Theorique, CNRS, Ecole Polytechnique, F-91128 Palaiseau (France); Faccio, D. [Dipartimento di Fisica e Matematica, Universita del'Insubria, Via Valleggio 11, I-22100 Como (Italy); School of Engineering and Physical Sciences, SUPA, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Couairon, A. [Centre de Physique Theorique, CNRS, Ecole Polytechnique, F-91128 Palaiseau (France); Papazoglou, D. G. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Materials Science and Technology Department, University of Crete, GR-71003 Heraklion (Greece); Panagiotopoulos, P.; Tzortzakis, S. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Abdollahpour, D. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1527, GR-71110 Heraklion (Greece); Physics Department, University of Crete, GR-71003 Heraklion (Greece)

    2011-08-15T23:59:59.000Z

    We demonstrate the existence of an additional class of stationary accelerating Airy wave forms that exist in the presence of third-order (Kerr) nonlinearity and nonlinear losses. Numerical simulations and experiments, in agreement with the analytical model, highlight how these stationary solutions sustain the nonlinear evolution of Airy beams. The generic nature of the Airy solution allows extension of these results to other settings, and a variety of applications are suggested.

  16. Axion beams at HERA?

    E-Print Network [OSTI]

    K. Piotrzkowski

    2007-01-09T23:59:59.000Z

    If the recently observed anomaly in the PVLAS experiment is due to the axion, then the powerful beams of synchrotron photons, propagating through high magnetic field of the HERA beamline, become strong axion sources. This gives a unique opportunity of detection of the axion-photon interactions by installing a small detector in the HERA tunnel, and to corroborate the axion hypothesis within a few days of running.

  17. High-Flux Microchannel Solar Receiver

    Broader source: Energy.gov [DOE]

    This fact sheet describes a high-flux, microchannel solar receiver project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by Oregon State University, is working to demonstrate a microchannel-based solar receiver capable of absorbing high solar flux, while using a variety of liquid and gaseous working fluids. High-flux microchannel receivers have the potential to dramatically reduce the size and cost of a solar receiver by minimizing re-radiation and convective losses.

  18. Eddy Correlation Flux Measurement System (ECOR) Handbook

    SciTech Connect (OSTI)

    Cook, DR

    2011-01-31T23:59:59.000Z

    The eddy correlation (ECOR) flux measurement system provides in situ, half-hour measurements of the surface turbulent fluxes of momentum, sensible heat, latent heat, and carbon dioxide (CO2) (and methane at one Southern Great Plains extended facility (SGP EF) and the North Slope of Alaska Central Facility (NSA CF). The fluxes are obtained with the eddy covariance technique, which involves correlation of the vertical wind component with the horizontal wind component, the air temperature, the water vapor density, and the CO2 concentration.

  19. Calculating kinetics parameters and reactivity changes with continuous-energy Monte Carlo

    SciTech Connect (OSTI)

    Kiedrowski, Brian C [Los Alamos National Laboratory; Brown, Forrest B [Los Alamos National Laboratory; Wilson, Paul [UNIV. WISCONSIN

    2009-01-01T23:59:59.000Z

    The iterated fission probability interpretation of the adjoint flux forms the basis for a method to perform adjoint weighting of tally scores in continuous-energy Monte Carlo k-eigenvalue calculations. Applying this approach, adjoint-weighted tallies are developed for two applications: calculating point reactor kinetics parameters and estimating changes in reactivity from perturbations. Calculations are performed in the widely-used production code, MCNP, and the results of both applications are compared with discrete ordinates calculations, experimental measurements, and other Monte Carlo calculations.

  20. Understanding the Poor Resolution from Test Beam RunUnderstanding the Poor Resolution from Test Beam Run 2004 Straw Test beam results2004 Straw Test beam results

    E-Print Network [OSTI]

    1 Understanding the Poor Resolution from Test Beam RunUnderstanding the Poor Resolution from Test Beam Run aah #12;2 2004 Straw Test beam results2004 Straw Test beam results ! Doc # 3308 v#3 by A. Ledovskoy " Using Data from 2004 Test Beam " Used "triplet" method for beam nominally perpendicular to Straw

  1. Beam quality conversion factors for parallel-plate ionization chambers in MV photon beams

    SciTech Connect (OSTI)

    Muir, B. R.; McEwen, M. R.; Rogers, D. W. O. [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada); Institute for National Measurement Standards, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2012-03-15T23:59:59.000Z

    Purpose: To investigate the behavior of plane-parallel ion chambers in high-energy photon beams through measurements and Monte Carlo simulations. Methods: Ten plane-parallel ion chamber types were obtained from the major ion chamber manufacturers. Absorbed dose-to-water calibration coefficients are measured for these chambers and k{sub Q} factors are determined. In the process, the behaviors of the chambers are characterized through measurements of leakage currents, chamber settling in cobalt-60, polarity and ion recombination behavior, and long-term stability. Monte Carlo calculations of the absorbed dose to the air in the ion chamber and absorbed dose to water are obtained to calculate k{sub Q} factors. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors are investigated by varying material properties and chamber dimensions. Results: Chamber behavior was variable in MV photon beams, especially with regard to chamber leakage and ion recombination. The plane-parallel chambers did not perform as well as cylindrical chambers. Significant differences up to 1.5% were observed in calibration coefficients after a period of eight months although k{sub Q} factors were consistent on average within 0.17%. Chamber-to-chamber variations in k{sub Q} factors for chambers of the same type were at the 0.2% level. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors ranged between 0.34% and 0.50% depending on the chamber type. Average percent differences between measured and calculated k{sub Q} factors were - 0.02%, 0.18%, and - 0.16% for 6, 10, and 25 MV beams, respectively. Conclusions: Excellent agreement is observed on average at the 0.2% level between measured and Monte Carlo calculated k{sub Q} factors. Measurements indicate that the behavior of these chambers is not adequate for their use for reference dosimetry of high-energy photon beams without a more extensive QA program than currently used for cylindrical reference-class ion chambers.

  2. Tetrakis-amido high flux membranes

    DOE Patents [OSTI]

    McCray, S.B.

    1989-10-24T23:59:59.000Z

    Composite RO membranes of a microporous polymeric support and a polyamide reaction product of a tetrakis-aminomethyl compound and a polyacylhalide are disclosed, said membranes exhibiting high flux and good chlorine resistance.

  3. A low cost high flux solar simulator

    E-Print Network [OSTI]

    Codd, Daniel S.

    A low cost, high flux, large area solar simulator has been designed, built and characterized for the purpose of studying optical melting and light absorption behavior of molten salts. Seven 1500 W metal halide outdoor ...

  4. The Role and Detectability of the Charm Contribution to Ultra High Energy Neutrino Fluxes

    E-Print Network [OSTI]

    Raj Gandhi; Abhijit Samanta; Atsushi Watanabe

    2009-08-27T23:59:59.000Z

    It is widely believed that charm meson production and decay may play an important role in high energy astrophysical sources of neutrinos, especially those that are baryon-rich, providing an environment conducive to pp interactions. Using slow-jet supernovae (SJS) as an example of such a source, we study the detectability of high-energy neutrinos, paying particular attention to those produced from charmed-mesons. We highlight important distinguishing features in the ultra-high energy neutrino flux which would act as markers for the role of charm in the source. In particular, charm leads to significant event rates at higher energies, after the conventional (pi, K) neutrino fluxes fall off. We calculate event rates both for a nearby single source and for diffuse SJS fluxes for an IceCube-like detector. By comparing muon event rates for the conventional and prompt fluxes in different energy bins, we demonstrate the striking energy dependence in the rates induced by the presence of charm. We also show that it leads to an energy dependant flux ratio of shower to muon events, providing an additional important diagnostic tool for the presence of prompt neutrinos. Motivated by the infusion of high energy anti-electron neutrinos into the flux by charm decay, we also study the detectability of the Glashow resonance due to these sources.

  5. Magnetic flux noise in q-bits and SQUIDS from primordial density fluctuations

    E-Print Network [OSTI]

    Christian Beck

    2014-09-16T23:59:59.000Z

    The understanding of the origin of $1/f$ magnetic flux noise commonly observed in superconducting devices such as SQUIDS and q-bits is still a major unsolved puzzle. Here we show that a significant part of the flux noise in superconducting Josephson devices may have a cosmological origin: As the Earth moves through a surrounding axionic dark matter condensate that has conserved the primordial power spectrum of density fluctuations, spatial fluctuations of the axion misalignment angle generate mirror temporal fluctuations of the superconducting phase difference in the junction. Our theory predicts the existence of flux noise with a power spectrum given by an $1/f^{2-n_s}$ spectrum, where $n_s=0.96$ is the spectral index of the near-scale invariant primordial density fluctuations. For the typical amplitude of this cosmologically generated universal flux noise we theoretically calculate the average value $\\delta \\Phi /\\Phi_0 =3.37 \\cdot 10^{-6}$ at 1Hz. These theoretical predictions are in excellent agreement with recent low-frequency flux noise measurements of various experimental groups. Magnetic flux noise, so far mainly considered as a nuisance for electronic devices, may thus contain valuable information about fluctuation spectra in the very early universe.

  6. Plasma-beam traps and radiofrequency quadrupole beam coolers

    SciTech Connect (OSTI)

    Maggiore, M., E-mail: mario.maggiore@lnl.infn.it; Cavenago, M.; Comunian, M.; Chirulotto, F.; Galatà, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S. [INFN-LNL, viale dell’Università 2, 35020 Legnaro (Italy)] [INFN-LNL, viale dell’Università 2, 35020 Legnaro (Italy); Caruso, A.; Longhitano, A. [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy)] [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy); Cavaliere, F.; Maero, G.; Paroli, B.; Pozzoli, R.; Romé, M. [INFN Sezione di Milano and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)] [INFN Sezione di Milano and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)

    2014-02-15T23:59:59.000Z

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  7. A scanning wire beam profile monitor

    SciTech Connect (OSTI)

    Steinbach, Ch.; van Rooij, M.

    1985-10-01T23:59:59.000Z

    The transverse profile of the circulating beam of the CERN PS is obtained from the interaction between the particles and a thin wire rapidly moving through it. The signal from a secondary particles monitor or the secondary emission current of the wire is sampled against the wire position every four beam revolutions in the machine. A stand-alone desk computer performs the real-time control of the wire displacement as well as the acquisitions and calculations necessary to display the profiles and the corresponding emittances. A traversing speed of 20 m/s in the measurement area is reached, using a high torque motor rigidly linked to a U shaped wire holder. All elements are carefully designed and chosen for low inertia and minimum load on the wire. This enables measurements of high energy beams of more than 10/sup 13/ p/p in the PS with negligible emittance blow-up due to multiple scattering. This blow-up is still acceptable at injection energy. A link to the PS main computer allows operation from any one of the main consoles.

  8. Sensitivity analysis of coupled criticality calculations

    SciTech Connect (OSTI)

    Perko, Z.; Kloosterman, J. L.; Lathouwers, D. [Delft Univ. of Technology, Faculty of Applied Physics, Dept. of Radiation, Radionuclides and Reactors, Mekelweg 15, 2629 JB, Delft (Netherlands)

    2012-07-01T23:59:59.000Z

    Perturbation theory based sensitivity analysis is a vital part of todays' nuclear reactor design. This paper presents an extension of standard techniques to examine coupled criticality problems with mutual feedback between neutronics and an augmenting system (for example thermal-hydraulics). The proposed procedure uses a neutronic and an augmenting adjoint function to efficiently calculate the first order change in responses of interest due to variations of the parameters describing the coupled problem. The effect of the perturbations is considered in two different ways in our study: either a change is allowed in the power level while maintaining criticality (power perturbation) or a change is allowed in the eigenvalue while the power is constrained (eigenvalue perturbation). The calculated response can be the change in the power level, the reactivity worth of the perturbation, or the change in any functional of the flux, the augmenting dependent variables and the input parameters. To obtain power- and criticality-constrained sensitivities power- and k-reset procedures can be applied yielding identical results. Both the theoretical background and an application to a one dimensional slab problem are presented, along with an iterative procedure to compute the necessary adjoint functions using the neutronics and the augmenting codes separately, thus eliminating the need of developing new programs to solve the coupled adjoint problem. (authors)

  9. Comparison of cosmic ray flux at sqrt(s) > 14 TeV with LHC luminosity

    E-Print Network [OSTI]

    Frank E. Taylor

    2008-05-29T23:59:59.000Z

    The high energy cosmic ray flux impinging on the sun and earth for 4 Gyr is compared to the operation of the CERN Large Hadron Collider (LHC) at design energy and luminosity. It is shown by two different calculations that both the integrated luminosity and the total hadronic interaction rate from the cosmic ray flux of comparable energy are many orders of magnitude larger than that of the LHC operated for 10 years. This study indicates that it is extremely unlikely that pernicious exotic particles, such as mini-black holes, would be produced by the LHC that would destroy the earth.

  10. Contribution to the local cosmic-ray flux from the Geminga supernova

    E-Print Network [OSTI]

    P. A. Johnson

    1994-04-06T23:59:59.000Z

    The contribution to the local cosmic-ray flux from the Geminga supernova is calculated assuming shock acceleration to 10^14 eV in a remnant which was formed several 10^5 years ago along with the Geminga pulsar. The particles are propagated to Earth using a simple diffusion model. In the region below the knee in the spectrum, it is found the supernova may contribute 10% of the local cosmic-ray flux, assuming plausible explosion parameters. The contribution to the amplitude of the anisotropy is not in conflict with the data in this energy region.

  11. au flux diffus: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    contribution of the GRB prompt and scattered emissions to the measured extragalactic gamma-ray flux. To estimate this contribution we optimistically require that the energy flux...

  12. Integration of Novel Flux Coupling Motor and Current Source Inverter...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Merit Review and Peer Evaluation ape034hsu2011p.pdf More Documents & Publications Integration of Novel Flux Coupling Motor and Current Source Inverter Novel Flux Coupling...

  13. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

    Broader source: Energy.gov (indexed) [DOE]

    Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR...

  14. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

    Broader source: Energy.gov (indexed) [DOE]

    Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of Appendix C to DOE G...

  15. A transport based one-dimensional perturbation code for reactivity calculations in metal systems

    SciTech Connect (OSTI)

    Wenz, T.R.

    1995-02-01T23:59:59.000Z

    A one-dimensional reactivity calculation code is developed using first order perturbation theory. The reactivity equation is based on the multi-group transport equation using the discrete ordinates method for angular dependence. In addition to the first order perturbation approximations, the reactivity code uses only the isotropic scattering data, but cross section libraries with higher order scattering data can still be used with this code. The reactivity code obtains all the flux, cross section, and geometry data from the standard interface files created by ONEDANT, a discrete ordinates transport code. Comparisons between calculated and experimental reactivities were done with the central reactivity worth data for Lady Godiva, a bare uranium metal assembly. Good agreement is found for isotopes that do not violate the assumptions in the first order approximation. In general for cases where there are large discrepancies, the discretized cross section data is not accurately representing certain resonance regions that coincide with dominant flux groups in the Godiva assembly. Comparing reactivities calculated with first order perturbation theory and a straight {Delta}k/k calculation shows agreement within 10% indicating the perturbation of the calculated fluxes is small enough for first order perturbation theory to be applicable in the modeled system. Computation time comparisons between reactivities calculated with first order perturbation theory and straight {Delta}k/k calculations indicate considerable time can be saved performing a calculation with a perturbation code particularly as the complexity of the modeled problems increase.

  16. Observations of beam-beam effects at the LHC

    E-Print Network [OSTI]

    Papotti, G; Herr, W; Giachino, R; Pieloni, T

    2014-01-01T23:59:59.000Z

    This paper introduces a list of observations related to the beam-beam interaction that were collected over the first years of LHC proton physics operation (2010-12). Beam-beam related effects not only have been extensively observed and recorded, but have also shaped the operation of the LHC for high-intensity proton running in a number of ways: the construction of the filling scheme, the choice of luminosity levelling techniques, measures to mitigate instabilities, and the choice of settings for improving performance (e.g. to reduce losses), among others.

  17. Precision Absolute Beam Current Measurement of Low Power Electron Beam

    SciTech Connect (OSTI)

    Ali, M. M.; Bevins, M. E.; Degtiarenko, P.; Freyberger, A.; Krafft, G. A.

    2012-11-01T23:59:59.000Z

    Precise measurements of low power CW electron beam current for the Jefferson Lab Nuclear Physics program have been performed using a Tungsten calorimeter. This paper describes the rationale for the choice of the calorimeter technique, as well as the design and calibration of the device. The calorimeter is in use presently to provide a 1% absolute current measurement of CW electron beam with 50 to 500 nA of average beam current and 1-3 GeV beam energy. Results from these recent measurements will also be presented.

  18. Neutral Beam Excitation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337, 2011 at3, Issue 30 NewNetworks,Beam

  19. Nanostructuring superconductors by ion beams: A path towards materials engineering

    SciTech Connect (OSTI)

    Gerbaldo, Roberto; Ghigo, Gianluca; Gozzelino, Laura; Laviano, Francesco [Department of Applied Science and Technology, Politecnico di Torino c.so Duca degli Abruzzi 24, 10129 Torino, Italy and INFN Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Amato, Antonino; Rovelli, Alberto [INFN Laboratori Nazionali del Sud, via S. Sofia 62, 95125 Catania (Italy); Cherubini, Roberto [INFN Laboratori Nazionali di Legnaro, viale dell'Universita 2, 35020 Legnaro (Italy)

    2013-07-18T23:59:59.000Z

    The paper deals with nanostructuring of superconducting materials by means of swift heavy ion beams. The aim is to modify their structural, optical and electromagnetic properties in a controlled way, to provide possibility of making them functional for specific applications. Results are presented concerning flux pinning effects (implantation of columnar defects with nanosize cross section to enhance critical currents and irreversibility fields), confined flux-flow and vortex guidance, design of devices by locally tailoring the superconducting material properties, analysis of disorder-induced effects in multi-band superconductors. These studies were carried out on different kinds of superconducting samples, from single crystals to thin films, from superconducting oxides to magnesium diboride, to recently discovered iron-based superconductors.

  20. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    E-Print Network [OSTI]

    Suerfu, Burkhant

    2015-01-01T23:59:59.000Z

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pio...

  1. Beam emittance measurements at Fermilab

    SciTech Connect (OSTI)

    Wendt, Manfred; Eddy, Nathan; Hu, Martin; Scarpine, Victor; Syphers, Mike; Tassotto, Gianni; Thurman-Keup, Randy; Yang, Ming-Jen; Zagel, James; /Fermilab

    2008-01-01T23:59:59.000Z

    We give short overview of various beam emittance measurement methods, currently applied at different machine locations for the Run II collider physics program at Fermilab. All these methods are based on beam profile measurements, and we give some examples of the related instrumentation techniques. At the end we introduce a multi-megawatt proton source project, currently under investigation at Fermilab, with respect to the beam instrumentation challenges.

  2. Modified floor response spectra for the Brookhaven National Laboratory High Flux Beam Reactor (HFBR)

    SciTech Connect (OSTI)

    Morante, R.J.; Skonieczny, J.

    1994-03-01T23:59:59.000Z

    This report documents the modified floor response spectra that will be used for future seismic evaluations of structures, systems, and components (SSC`s) within the HFBR and the technical basis for the modified floor response spectra. When used within this report, the term ``current spectra`` refers to the 1978 spectra developed in BNL Informal Report BNL-26019.

  3. Production flux of sea spray aerosol

    SciTech Connect (OSTI)

    de Leeuw, G.; Lewis, E.; Andreas, E. L.; Anguelova, M. D.; Fairall, C. W.; O’Dowd, C.; Schulz, M.; Schwartz, S. E.

    2011-05-07T23:59:59.000Z

    Knowledge of the size- and composition-dependent production flux of primary sea spray aerosol (SSA) particles and its dependence on environmental variables is required for modeling cloud microphysical properties and aerosol radiative influences, interpreting measurements of particulate matter in coastal areas and its relation to air quality, and evaluating rates of uptake and reactions of gases in sea spray drops. This review examines recent research pertinent to SSA production flux, which deals mainly with production of particles with r{sub 80} (equilibrium radius at 80% relative humidity) less than 1 {micro}m and as small as 0.01 {micro}m. Production of sea spray particles and its dependence on controlling factors has been investigated in laboratory studies that have examined the dependences on water temperature, salinity, and the presence of organics and in field measurements with micrometeorological techniques that use newly developed fast optical particle sizers. Extensive measurements show that water-insoluble organic matter contributes substantially to the composition of SSA particles with r{sub 80} < 0.25 {micro}m and, in locations with high biological activity, can be the dominant constituent. Order-of-magnitude variation remains in estimates of the size-dependent production flux per white area, the quantity central to formulations of the production flux based on the whitecap method. This variation indicates that the production flux may depend on quantities such as the volume flux of air bubbles to the surface that are not accounted for in current models. Variation in estimates of the whitecap fraction as a function of wind speed contributes additional, comparable uncertainty to production flux estimates.

  4. Low energy beta-beams

    E-Print Network [OSTI]

    Cristina Volpe

    2009-11-13T23:59:59.000Z

    The main goal of a beta-beam facility is to determine the possible existence of CP violation in the lepton sector, the value of the third neutrino mixing angle and the mass hierarchy. Here we argue that a much broader physics case can be covered since the beta-beam concept can also be used to establish a low energy beta-beam facility. We discuss that the availability of neutrino beams in the 100 MeV energy range offers a unique opportunity to perform neutrino scattering experiments of interest for nuclear physics, for the study of fundamental interactions and of core-collapse supernova physics.

  5. First LHC Beams in ATLAS

    E-Print Network [OSTI]

    Krieger, P

    2009-01-01T23:59:59.000Z

    This is a talk on the ATLAS single beam running, to be given on February 9th at the Aspen Winter Conference.

  6. ANL Beams and Applications Seminar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    characterization of the laser and electron beams of the Cornell Energy Recovery Linac Heng Li Cornell University June 18 Interbeam Scattering Studies at CesrTA Michael Ehrlichman...

  7. Broad-band beam buncher

    DOE Patents [OSTI]

    Goldberg, David A. (Walnut Creek, CA); Flood, William S. (Berkeley, CA); Arthur, Allan A. (Martinez, CA); Voelker, Ferdinand (Orinda, CA)

    1986-01-01T23:59:59.000Z

    A broad-band beam buncher is disclosed, comprising an evacuated housing, an electron gun therein for producing an electron beam, a buncher cavity having entrance and exit openings through which the beam is directed, grids across such openings, a source providing a positive DC voltage between the cavity and the electron gun, a drift tube through which the electron beam travels in passing through such cavity, grids across the ends of such drift tube, gaps being provided between the drift tube grids and the entrance and exit grids, a modulator for supplying an ultrahigh frequency modulating signal to the drift tube for producing velocity modulation of the electrons in the beam, a drift space in the housing through which the velocity modulated electron beam travels and in which the beam is bunched, and a discharge opening from such drift tube and having a grid across such opening through which the bunched electron beam is discharged into an accelerator or the like. The buncher cavity and the drift tube may be arranged to constitute an extension of a coaxial transmission line which is employed to deliver the modulating signal from a signal source. The extended transmission line may be terminated in its characteristic impedance to afford a broad-band response and the device as a whole designed to effect broad-band beam coupling, so as to minimize variations of the output across the response band.

  8. Transition between wurtzite and zinc-blende GaN: An effect of deposition condition of molecular-beam epitaxy

    SciTech Connect (OSTI)

    Shi, B. M.; Xie, M. H.; Wu, H. S.; Wang, N.; Tong, S. Y. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tang, Hong Kong (China)

    2006-10-09T23:59:59.000Z

    GaN exists in both wurtzite and zinc-blende phases and the growths of the two on its (0001) or (111) surfaces are achieved by choosing proper deposition conditions of molecular-beam epitaxy (MBE). At low substrate temperatures but high gallium fluxes, metastable zinc-blende GaN films are obtained, whereas at high temperatures and/or using high nitrogen fluxes, equilibrium wurtzite phase GaN epilayers resulted. This dependence of crystal structure on substrate temperature and source flux is not affected by deposition rate. Rather, the initial stage nucleation kinetics plays a primary role in determining the crystallographic structures of epitaxial GaN by MBE.

  9. CALCULATING INTERIOR DAYLIGHT ILLUMINATION WITH A PROGRAMMABLE HAND CALCULATOR

    E-Print Network [OSTI]

    Bryan, Harvey J.

    2013-01-01T23:59:59.000Z

    Committee E-3.2, "Daylight: International RecommendationsCalculation of Natural Daylight," CIE PUBLICATION No. 16,Committee E-3.2, "Natural Daylight: Official Recommenda-

  10. CALCULATING INTERIOR DAYLIGHT ILLUMINATION WITH A PROGRAMMABLE HAND CALCULATOR

    E-Print Network [OSTI]

    Bryan, Harvey J.

    2013-01-01T23:59:59.000Z

    Committee E-3.2, "Daylight: International Recommendationsthe Calculation of Natural Daylight, 11 CIE PUBLICATION No.Committee E-3.2 1 "Natural Daylight: Official Recommenda-

  11. Comparison of laser-induced surface damage density measurements with small and large beams: toward representativeness

    SciTech Connect (OSTI)

    Lamaignere, Laurent; Dupuy, Gabriel; Donval, Thierry; Grua, Pierre; Bercegol, Herve

    2011-02-01T23:59:59.000Z

    Pulsed laser damage density measurements obtained with diverse facilities are difficult to compare, due to the interplay of numerous parameters, such as beam area and pulse geometry, which, in operational large beam conditions, are very different from laboratory measurements. This discrepancy could have a significant impact; if so, one could not even pretend that laser damage density control is a real measurement process. In this paper, this concern is addressed. Tests with large beams of centimeter size on a high-power laser facility have beam performed according to a parametric study and are compared to small beam laboratory tests. It is shown that laser damage densities obtained with large and small beams are equal, within calculated error bars.

  12. SU-E-T-50: Automatic Validation of Megavoltage Beams Modeled for Clinical Use in Radiation Therapy

    SciTech Connect (OSTI)

    Melchior, M [Terapia Radiante S.A., La Plata, Buenos Aires (Argentina); Salinas Aranda, F [Vidt Centro Medico, Ciudad Autonoma De Buenos Aires (Argentina); 21st Century Oncology, Ft. Myers, FL (United States); Sciutto, S [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Dodat, D [Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina); Larragueta, N [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina)

    2014-06-01T23:59:59.000Z

    Purpose: To automatically validate megavoltage beams modeled in XiO™ 4.50 (Elekta, Stockholm, Sweden) and Varian Eclipse™ Treatment Planning Systems (TPS) (Varian Associates, Palo Alto, CA, USA), reducing validation time before beam-on for clinical use. Methods: A software application that can automatically read and analyze DICOM RT Dose and W2CAD files was developed using MatLab integrated development environment.TPS calculated dose distributions, in DICOM RT Dose format, and dose values measured in different Varian Clinac beams, in W2CAD format, were compared. Experimental beam data used were those acquired for beam commissioning, collected on a water phantom with a 2D automatic beam scanning system.Two methods were chosen to evaluate dose distributions fitting: gamma analysis and point tests described in Appendix E of IAEA TECDOC-1583. Depth dose curves and beam profiles were evaluated for both open and wedged beams. Tolerance parameters chosen for gamma analysis are 3% and 3 mm dose and distance, respectively.Absolute dose was measured independently at points proposed in Appendix E of TECDOC-1583 to validate software results. Results: TPS calculated depth dose distributions agree with measured beam data under fixed precision values at all depths analyzed. Measured beam dose profiles match TPS calculated doses with high accuracy in both open and wedged beams. Depth and profile dose distributions fitting analysis show gamma values < 1. Relative errors at points proposed in Appendix E of TECDOC-1583 meet therein recommended tolerances.Independent absolute dose measurements at points proposed in Appendix E of TECDOC-1583 confirm software results. Conclusion: Automatic validation of megavoltage beams modeled for their use in the clinic was accomplished. The software tool developed proved efficient, giving users a convenient and reliable environment to decide whether to accept or not a beam model for clinical use. Validation time before beam-on for clinical use was reduced to a few hours.

  13. Absolute Calibration of the Radio Astronomy Flux Density Scale at 22 to 43 GHz Using Planck

    E-Print Network [OSTI]

    Partridge, B; Perley, R A; Stevens, J; Butler, B J; Rocha, G; Walter, B; Zacchei, A

    2015-01-01T23:59:59.000Z

    The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite's annual motion around the Sun and the temperature of the cosmic microwave background), and its beams are well characterized at sub-percent levels. Thus Planck's flux density measurements of compact sources are absolute in the same sense. We have made coordinated VLA and ATCA observations of 65 strong, unresolved Planck sources in order to transfer Planck's calibration to ground-based instruments at 22, 28, and 43 GHz. The results are compared to microwave flux density scales currently based on planetary observations. Despite the scatter introduced by the variability of many of the sources, the flux density scales are determined to 1-2% accuracy. At 28 GHz, the flux density scale used by the VLA runs 3.6% +- 1.0% below Planck values; at 43 GHz, the discrepancy increases to 6.2% +- 1.4% for both ATCA and the VLA.

  14. Combining tissue-phantom ratios to provide a beam-quality specifier for flattening filter free photon beams

    SciTech Connect (OSTI)

    Dalaryd, Mårten, E-mail: Marten.Dalaryd@med.lu.se; Knöös, Tommy [Department of Clinical Sciences, Medical Radiation Physics, Lund University, P.O. Box 117, Lund SE-221 00, Sweden and Radiation Physics, Skåne University Hospital, Lund SE-221 85 (Sweden); Ceberg, Crister [Department of Clinical Sciences, Medical Radiation Physics, Lund University, P.O. Box 117, Lund SE-221 00 (Sweden)

    2014-11-01T23:59:59.000Z

    Purpose: There are currently several commercially available radiotherapy treatment units without a flattening filter in the beam line. Unflattened photon beams have an energy and lateral fluence distribution that is different from conventional beams and, thus, their attenuation properties differ. As a consequence, for flattening filter free (FFF) beams, the relationship between the beam-quality specifier TPR{sub 20,10} and the Spencer–Attix restricted water-to-air mass collision stopping-power ratios, (L{sup -}/?){sub air}{sup water}, may have to be refined in order to be used with equivalent accuracy as for beams with a flattening filter. The purpose of this work was twofold. First, to study the relationship between TPR{sub 20,10} and (L{sup -}/?){sub air}{sup water} for FFF beams, where the flattening filter has been replaced by a metal plate as in most clinical FFF beams. Second, to investigate the potential of increasing the accuracy in determining (L{sup -}/?){sub air}{sup water} by adding another beam-quality metric, TPR{sub 10,5}. The relationship between (L{sup -}/?){sub air}{sup water} and %dd(10){sub x} for beams with and without a flattening filter was also included in this study. Methods: A total of 24 realistic photon beams (10 with and 14 without a flattening filter) from three different treatment units have been used to calculate (L{sup -}/?){sub air}{sup water}, TPR{sub 20,10}, and TPR{sub 10,5} using the EGSnrc Monte Carlo package. The relationship between (L{sup -}/?){sub air}{sup water} and the dual beam-quality specifier TPR{sub 20,10} and TPR{sub 10,5} was described by a simple bilinear equation. The relationship between the photon beam-quality specifier %dd(10){sub x} used in the AAPM’s TG-51 dosimetry protocol and (L{sup -}/?){sub air}{sup water} was also investigated for the beams used in this study, by calculating the photon component of the percentage depth dose at 10 cm depth with SSD 100 cm. Results: The calculated (L{sup -}/?){sub air}{sup water} for beams without a flattening filter was 0.3% lower, on average, than for beams with a flattening filter and comparable TPR{sub 20,10}. Using the relationship in IAEA, TRS-398 resulted in a root mean square deviation (RMSD) of 0.0028 with a maximum deviation of 0.0043 (0.39%) from Monte Carlo calculated values. For all beams in this study, the RMSD between the proposed model and the Monte Carlo calculated values was 0.0006 with a maximum deviation of 0.0013 (0.1%). Using an earlier proposed relationship [Xiong and Rogers, Med. Phys. 35, 2104–2109 (2008)] between %dd(10){sub x} and (L{sup -}/?){sub air}{sup water} gave a RMSD of 0.0018 with a maximum deviation of 0.0029 (0.26%) for all beams in this study (compared to RMSD 0.0015 and a maximum deviation of 0.0048 (0.47%) for the relationship used in AAPM TG-51 published by Almond et al. [Med. Phys. 26, 1847–1870 (1999)]). Conclusions: Using TPR{sub 20,10} as a beam-quality specifier, for the flattening filter free beams used in this study, gave a maximum difference of 0.39% between (L{sup -}/?){sub air}{sup water} predicted using IAEA TRS-398 and Monte Carlo calculations. An additional parameter for determining (L{sup -}/?){sub air}{sup water} has been presented. This parameter is easy to measure; it requires only an additional dose measurement at 5 cm depth with SSD 95 cm, and provides information for accurate determination of the (L{sup -}/?){sub air}{sup water} ratio for beams both with and without a flattening filter at the investigated energies.

  15. NEUTRAL-BEAM INJECTION

    SciTech Connect (OSTI)

    Kunkel, W.B.

    1980-06-01T23:59:59.000Z

    The emphasis in the preceding chapters has been on magnetic confinement of high temperature plasmas. The question of production and heating of such plasmas has been dealt with relatively more briefly. It should not be inferred, however, that these matters must therefore be either trivial or unimportant. A review of the history reveals that in the early days all these aspects of the controlled fusion problem were considered to be on a par, and were tackled simultaneously and with equal vigor. Only the confinement problem turned out to be much more complex than initially anticipated, and richer in challenge to the plasma physicist than the questions of plasma production and heating. On the other hand, the properties of high-temperature plasmas and plasma confinement can only be studied experimentally after the problems of production and of heating to adequate temperatures are solved. It is the purpose of this and the next chapter to supplement the preceding discussions with more detail on two important subjects: neutral-beam injection and radio-frequency heating. These are the major contenders for heating in present and future tokamak and mirror fusion experiments, and even in several proposed reactors. For neutral beams we emphasize here the technology involved, which has undergone a rather remarkable development. The physics of particle and energy deposition in the plasma, and the discussion of the resulting effects on the confined plasma, have been included in previous chapters, and some experimental results are quoted there. Other heating processes of relevance to fusion are mentioned elsewhere in this book, in connection with the experiments where they are used: i.e. ohmic heating, adiabatic compression heating, and alpha-particle heating in Chapter 3 by H.P. Furth; more ohmic heating in Chapter 7, and shock-implosion heating, laser heating, and relativistic-electron beam heating in Chapter 8, both by W. E. Quinn. These methods are relatively straightforward in their physics and their technology, or in any case they are considered to be adequately covered by these other authors.

  16. FFTF (Fast Flux Test Facility) reactor shutdown system reliability reevaluation

    SciTech Connect (OSTI)

    Pierce, B.F.

    1986-07-01T23:59:59.000Z

    The reliability analysis of the Fast Flux Test Facility reactor shutdown system was reevaluated. Failure information based on five years of plant operating experience was used to verify original reliability numbers or to establish new ones. Also, system modifications made subsequent to performance of the original analysis were incorporated into the reevaluation. Reliability calculations and sensitivity analyses were performed using a commercially available spreadsheet on a personal computer. The spreadsheet was configured so that future failures could be tracked and compared with expected failures. A number of recommendations resulted from the reevaluation including both increased and decreased surveillance intervals. All recommendations were based on meeting or exceeding existing reliability goals. Considerable cost savings will be incurred upon implementation of the recommendations.

  17. A high power beam-on-target test of liquid lithium target for RIA.

    SciTech Connect (OSTI)

    Nolen, J.; Reed, C.; Novick, V.; Specht, J.; Plotkin, P.; Momozaki,Y.; Gomes, I.

    2005-08-29T23:59:59.000Z

    Experiments were conducted to demonstrate the stable operation of a windowless liquid lithium target under extreme thermal loads that are equivalent to uranium beams from the proposed Rare Isotope Accelerator (RIA) driver linac. The engineering and safety issues accompanying liquid lithium systems are first discussed. The liquid metal technology knowledge base generated primarily for fast reactors, and liquid metal cooled fusion reactors, was applied to the development of these systems in a nuclear physics laboratory setting. The use of a high energy electron beam for simulating a high power uranium beam produced by the RIA driver linac is also described. Calculations were performed to obtain energy deposition profiles produced by electron beams at up to a few MeV to compare with expected uranium beam energy deposition profiles. It was concluded that an experimental simulation using a 1-MeV electron beam would be a valuable tool to assess beam-jet interaction. In the experiments, the cross section of the windowless liquid lithium target was 5 mm x 10 mm, which is a 1/3rd scale prototype target, and the velocity of the liquid lithium was varied up to 6 m/s. Thermal loads up to 20 kW within a beam spot diameter of 1mm were applied on the windowless liquid lithium target by the 1-MeV electron beam. The calculations showed that the maximum power density and total power deposited within the target, from the electron beam, was equivalent to that of a 200-kW, 400-MeV/u uranium beam. It was demonstrated that the windowless liquid lithium target flowing at velocities as low as 1.8 m/s stably operated under beam powers up to 20 kW without disruption or excessive vaporization.

  18. Coronal mass ejections and magnetic flux buildup in the heliosphere

    E-Print Network [OSTI]

    California at Berkeley, University of

    electron heat flux. The first panel shows the preeruption heliospheric flux, which consists of the an open the observed doubling in the magnetic field intensity at 1 AU over the solar cycle. Such timescales signatures; no flux buildup results. The dynamic simulation yields a solar cycle flux variation with high

  19. Calculation of the transverse kicks generated by the bends of a hollow electron lens

    SciTech Connect (OSTI)

    Stancari, Giulio

    2014-03-25T23:59:59.000Z

    Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam in high-energy accelerators. They were used in the Fermilab Tevatron collider for abort-gap clearing, beam-beam compensation, and halo scraping. A beam-beam compensation scheme based upon electron lenses is currently being implemented in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. This work is in support of a conceptual design of hollow electron beam scraper for the Large Hadron Collider. It also applies to the implementation of nonlinear integrable optics with electron lenses in the Integrable Optics Test Accelerator at Fermilab. We consider the axial asymmetries of the electron beam caused by the bends that are used to inject electrons into the interaction region and to extract them. A distribution of electron macroparticles is deposited on a discrete grid enclosed in a conducting pipe. The electrostatic potential and electric fields are calculated using numerical Poisson solvers. The kicks experienced by the circulating beam are estimated by integrating the electric fields over straight trajectories. These kicks are also provided in the form of interpolated analytical symplectic maps for numerical tracking simulations, which are needed to estimate the effects of the electron lens imperfections on proton lifetimes, emittance growth, and dynamic aperture. We outline a general procedure to calculate the magnitude of the transverse proton kicks, which can then be generalized, if needed, to include further refinements such as the space-charge evolution of the electron beam, magnetic fields generated by the electron current, and longitudinal proton dynamics.

  20. Wide dynamic range neutron flux monitor having fast time response for the Large Helical Device

    SciTech Connect (OSTI)

    Isobe, M., E-mail: isobe@nifs.ac.jp; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan); Department of Fusion Science, The Graduate University for Advanced Studies, Toki 509-5292 (Japan); Ogawa, K.; Miyake, H.; Hayashi, H.; Kobuchi, T. [National Institute for Fusion Science, Toki 509-5292 (Japan); Nakano, Y.; Watanabe, K.; Uritani, A. [Department of Materials, Physics and Energy Engineering, Nagoya University, Nagoya 464-8603 (Japan); Misawa, T. [Kyoto University Research Reactor Institute, Kumatori 590-0494 (Japan); Nishitani, T. [Japan Atomic Energy Agency, Rokkasho 039-3212 (Japan); Tomitaka, M.; Kumagai, T.; Mashiyama, Y.; Ito, D.; Kono, S. [Toshiba Corporation, Fuchu 183-8511 (Japan); Yamauchi, M. [Toshiba Nuclear Engineering Services Corporation, Yokohama 235-8523 (Japan)

    2014-11-15T23:59:59.000Z

    A fast time response, wide dynamic range neutron flux monitor has been developed toward the LHD deuterium operation by using leading-edge signal processing technologies providing maximum counting rate up to ?5 × 10{sup 9} counts/s. Because a maximum total neutron emission rate over 1 × 10{sup 16} n/s is predicted in neutral beam-heated LHD plasmas, fast response and wide dynamic range capabilities of the system are essential. Preliminary tests have demonstrated successful performance as a wide dynamic range monitor along the design.

  1. Laser acceleration of ion beams

    E-Print Network [OSTI]

    I. A. Egorova; A. V. Filatov; A. V. Prozorkevich; S. A. Smolyansky; D. B. Blaschke; M. Chubaryan

    2007-02-01T23:59:59.000Z

    We consider methods of charged particle acceleration by means of high-intensity lasers. As an application we discuss a laser booster for heavy ion beams provided, e.g. by the Dubna nuclotron. Simple estimates show that a cascade of crossed laser beams would be necessary to provide additional acceleration to gold ions of the order of GeV/nucleon.

  2. Head-on beam-beam collisions with high intensities and long range beam-beam studies in the LHC

    E-Print Network [OSTI]

    Albert, M; Assmann, R; Buffat, X; Calaga, R; Cornelis, K; Fitterer, M; Giachino, R; Herr, W; Miyamoto, R; Norman, L; Papotti, G; Pieloni, T; Ponce, L; Redaelli, S; Schaumann, M; Trad, G; Wollmann, D

    2011-01-01T23:59:59.000Z

    In two experiments we studied possible limitations due to the beam-beam effects in the LHC. In the first experiment we collided high intensity bunches head-on to explore the region for high luminosity collisions. In the second test we reduced the crossing angle in the presence of long range encounters to increase their effects.

  3. Uniform flux dish concentrators for photovoltaic application

    SciTech Connect (OSTI)

    Jorgensen, G; Wendelin, T

    1992-05-01T23:59:59.000Z

    Researchers at the National Renewable Energy Laboratory (NREL) have designed a unique and innovative molded dish concentrator capable of producing a uniform flux profile on a flat target plane. Concentration levels of 100--200 suns, which are uniform over an area of several square inches, can be directly achieved for collection apertures of a reasonable size ({approximately}1.5-m diameter). Such performance would be immediately applicable to photovoltaic (PV) use. Economic concerns have shown that the proposed approach would be less expensive thatn Fresnel lens concepts or other dish concentrator designs that require complicated and costly receivers to mix the flux to obtain a uniform distribution. 12 refs.

  4. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, Fulvio (Rome, IT); Cohen, Samuel A. (Hopewell, NJ); Bennett, Timothy (Princeton, NJ); Timberlake, John R. (Allentown, NJ)

    1993-01-01T23:59:59.000Z

    Invention comprises an instrument in which momentum flux onto a biasable target plate is transferred via a suspended quartz tube onto a sensitive force transducer--a capacitance-type pressure gauge. The transducer is protected from thermal damage, arcing and sputtering, and materials used in the target and pendulum are electrically insulating, rigid even at elevated temperatures, and have low thermal conductivity. The instrument enables measurement of small forces (10.sup.-5 to 10.sup.3 N) accompanied by high heat fluxes which are transmitted by energetic particles with 10's of eV of kinetic energy in a intense magnetic field and pulsed plasma environment.

  5. Dual neutron flux/temperature measurement sensor

    DOE Patents [OSTI]

    Mihalczo, J.T.; Simpson, M.L.; McElhaney, S.A.

    1994-10-04T23:59:59.000Z

    Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive 6LiF and the second is a rare-earth activated Y203 thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination. 3 figs.

  6. Studies of beam dynamics in relativistic klystron two-beam accelerators

    SciTech Connect (OSTI)

    Lidia, Steven M.

    1999-11-01T23:59:59.000Z

    Two-beam accelerators (TBAs) based upon free-electron lasers (FELs) or relativistic klystrons (RK-TBAs) have been proposed as efficient power sources for next generation high-energy linear colliders. Studies have demonstrated the possibility of building TBAs from X-band ({approximately}8-12 GHz) through Ka band ({approximately} 30-35 GHz) frequency regions. Provided that further prototyping shows stable beam propagation with minimal current loss and production of good quality, high-power rf fields, this technology is compatible with current schemes for electron-positron colliders in the multi-TeV center-of-mass scale. A new method of simulating the beam dynamics in accelerators of this type has been developed in this dissertation. There are three main components to this simulation. The first is a tracking algorithm to generate nonlinear transfer maps for pushing noninteracting particles through the external fields. The second component is a 3D Particle-In-Cell (PIC) algorithm that solves a set of Helmholtz equations for the self-fields, including the conducting boundary condition, and generates impulses that are interleaved with the nonlinear maps by means of a split-operation algorithm. The Helmholtz equations are solved by a multi-grid algorithm. The third component is an equivalent circuit equation solver that advances the modal rf cavity fields in time due to excitation by the modulated beam. The RTA project is described, and the simulation code is used to design the latter portions of the experiment. Detailed calculations of the beam dynamics and of the rf cavity output are presented and discussed. A beamline design is presented that will generate nearly 1.2 GW of power from 40 input, gain, and output rv cavities over a 10 m distance. The simulations show that beam current losses are acceptable, and that longitudinal and transverse focusing techniques are sufficient capable of maintaining a high degree of beam quality along the entire beamline. Additional experimental efforts are also described.

  7. Toward automated beam optics control

    SciTech Connect (OSTI)

    Silbar, R.R.; Schultz, D.E.

    1987-01-01T23:59:59.000Z

    We have begun a program aiming toward automatic control of charged-particle beam optics using artificial intelligence programming techniques. In developing our prototype, we are working with LISP machines and the KEE expert system shell. Our first goal was to develop a ''mouseable'' representation of a typical beam line. This responds actively to changes entered from the mouse or keyboard, giving an updated display of the beam line itself, its optical properties, and the instrumentation and control devices as seen by the operater. We have incorporated TRANSPORT, written in Fortran but running as a callable procedure in the LISP environment, for simulation of the beam-line optics. This paper describes the experience gained in meeting our first goal and discusses plans to extend the work so that it is usable, in realtime, on an operating beam line. 11 refs.

  8. Constraints on GRB TeV Emission from the GeV Extragalactic Diffuse Gamma-Ray Flux

    E-Print Network [OSTI]

    Casanova, S; Zhang, B; Zhang, Bing

    2006-01-01T23:59:59.000Z

    TeV gamma rays emitted by GRBs are converted into electron-positron pairs via interactions with the extragalactic infrared radiation fields. In turn the pairs produced, whose trajectories are randomized by magnetic fields, will inverse Compton scatter off the cosmic microwave background photons. The beamed TeV gamma ray flux from GRBs is thus transformed into a GeV isotropic gamma ray flux, which contributes to the total extragalactic gamma-ray background emission. Assuming a model for the extragalactic radiation fields, for the GRB redshift distribution and for the GRB luminosity function, we use the measured GeV extragalactic gamma-ray flux to set upper limits on the GRB emission in TeV gamma rays that is predicted in several models.

  9. Global variance reduction for Monte Carlo reactor physics calculations

    SciTech Connect (OSTI)

    Zhang, Q.; Abdel-Khalik, H. S. [Department of Nuclear Engineering, North Carolina State University, P.O. Box 7909, Raleigh, NC 27695-7909 (United States)

    2013-07-01T23:59:59.000Z

    Over the past few decades, hybrid Monte-Carlo-Deterministic (MC-DT) techniques have been mostly focusing on the development of techniques primarily with shielding applications in mind, i.e. problems featuring a limited number of responses. This paper focuses on the application of a new hybrid MC-DT technique: the SUBSPACE method, for reactor analysis calculation. The SUBSPACE method is designed to overcome the lack of efficiency that hampers the application of MC methods in routine analysis calculations on the assembly level where typically one needs to execute the flux solver in the order of 10{sup 3}-10{sup 5} times. It places high premium on attaining high computational efficiency for reactor analysis application by identifying and capitalizing on the existing correlations between responses of interest. This paper places particular emphasis on using the SUBSPACE method for preparing homogenized few-group cross section sets on the assembly level for subsequent use in full-core diffusion calculations. A BWR assembly model is employed to calculate homogenized few-group cross sections for different burn-up steps. It is found that using the SUBSPACE method significant speedup can be achieved over the state of the art FW-CADIS method. While the presented speed-up alone is not sufficient to render the MC method competitive with the DT method, we believe this work will become a major step on the way of leveraging the accuracy of MC calculations for assembly calculations. (authors)

  10. FLUX SENSOR EVALUATIONS AT THE ATR CRITICAL FACILITY

    SciTech Connect (OSTI)

    Troy Unruh; Joy Rempe; David Nigg; George Imel; Jason Harris; Eric Bonebrake

    2010-11-01T23:59:59.000Z

    The Advanced Test Reactor (ATR) and the ATR Critical (ATRC) facilities lack real-time methods for detecting thermal neutron flux and fission reaction rates for irradiation capsules. Direct measurements of the actual power deposited into a test are now possible without resorting to complicated correction factors. In addition, it is possible to directly measure minor actinide fission reaction rates and to provide time-dependent monitoring of the fission reaction rate or fast/thermal flux during transient testing. A joint Idaho State University /Idaho National Laboratory ATR National Scientific User Facility (ATR NSUF) project was recently initiated to evaluate new real-time state-of-the-art in-pile flux detection sensors. Initially, the project is comparing the accuracy, response time, and long duration performance of French Atomic Energy Commission (CEA)-developed miniature fission chambers, specialized self-powered neutron detectors (SPNDs) by the Argentinean National Energy Commission (CNEA), specially developed commercial SPNDs, and back-to-back fission (BTB) chambers developed by Argonne National Laboratory (ANL). As discussed in this paper, specialized fixturing and software was developed by INL to facilitate these joint ISU/INL evaluations. Calculations were performed by ISU to assess the performance of and reduce uncertainties in flux detection sensors and compare data obtained from these sensors with existing integral methods employed at the ATRC. Ultimately, project results will be used to select the detector that can provide the best online regional ATRC power measurement. It is anticipated that project results may offer the potential to increase the ATRC’s current power limit and its ability to perform low-level irradiation experiments. In addition, results from this effort will provide insights about the viability of using these detectors in the ATR. Hence, this effort complements current activities to improve ATR software tools, computational protocols and in-core instrumentation under the ATR Modeling, Simulation and V&V Upgrade initiative, as well as the work to replace nuclear instrumentation under the ATR Life Extension Project (LEP) and provide support to the ATR NSUF.

  11. Calculating differential cross sections for electron-impact ionization without explicit use of the asymptotic form

    SciTech Connect (OSTI)

    McCurdy, C.W. [Computing Sciences, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Computing Sciences, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Rescigno, T.N. [Physics and Space Technology Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Physics and Space Technology Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1997-12-01T23:59:59.000Z

    We describe the calculation of singly differential (energy-sharing) cross sections for electron-impact ionization. First, using exterior complex scaling, we calculate the outgoing portion of the scattering wave function without explicit use of asymptotic boundary conditions. Once that wave function is known for a finite region of space, the outgoing flux can be calculated and extrapolated to large distances according to behavior that is specific to the ionization problem. The differential cross section is proportional to the outgoing flux in specific directions of a hyperspherical angle in the coordinates. Calculations on the singlet s-wave radial limit (Temkin-Poet and collinear) models of electron-hydrogen atom ionization are presented. {copyright} {ital 1997} {ital The American Physical Society}

  12. High-flux neutron source based on a liquid-lithium target

    SciTech Connect (OSTI)

    Halfon, S. [Soreq NRC, Yavne, 81800 (Israel) and Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Feinberg, G. [Soreq NRC, Yavne, 81800 (Israel) and Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Arenshtam, A.; Berkovits, D.; Kijel, D.; Nagler, A.; Eliyahu, I.; Silverman, I. [Soreq NRC, Yavne, 81800 (Israel)

    2013-04-19T23:59:59.000Z

    A prototype compact Liquid Lithium Target (LiLiT), able to constitute an accelerator-based intense neutron source, was built. The neutron source is intended for nuclear astrophysical research, boron neutron capture therapy (BNCT) in hospitals and material studies for fusion reactors. The LiLiT setup is presently being commissioned at Soreq Nuclear research Center (SNRC). The lithium target will produce neutrons through the {sup 7}Li(p,n){sup 7}Be reaction and it will overcome the major problem of removing the thermal power generated by a high-intensity proton beam, necessary for intense neutron flux for the above applications. The liquid-lithium loop of LiLiT is designed to generate a stable lithium jet at high velocity on a concave supporting wall with free surface toward the incident proton beam (up to 10 kW). During off-line tests, liquid lithium was flown through the loop and generated a stable jet at velocity higher than 5 m/s on the concave supporting wall. The target is now under extensive test program using a high-power electron-gun. Up to 2 kW electron beam was applied on the lithium flow at velocity of 4 m/s without any flow instabilities or excessive evaporation. High-intensity proton beam irradiation will take place at SARAF (Soreq Applied Research Accelerator Facility) superconducting linear accelerator currently in commissioning at SNRC.

  13. Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam

    E-Print Network [OSTI]

    McDonald, Kirk

    11 Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam: Lessons for the NextFACT08NuFACT08 ­­ 4 July4 July S. ChildressS. Childress ­­ Proton BeamsProton Beams 22 Presentation OutlinePresentation Outline Key Proton Beam ConsiderationsKey Proton Beam Considerations The First

  14. Remarks on D_p and D_{p-2} with each carrying a flux

    E-Print Network [OSTI]

    J. X. Lu; Shan-Shan Xu

    2009-09-04T23:59:59.000Z

    We explore various properties of interaction between D$_p$ and D$_{p'}$ with each carrying a worldvolume flux and with the $p'$-branes placed along $p'$ spatial worldvolume directions of the p-branes at a separation when $p - p' = 2$. Carefully analyzing the annulus amplitudes calculated via the boundary state approach, we find that many features of amplitudes remain similar to those studied when $p = p'$ such as the nature of force on the brane separation, the onset of various instabilities when the brane-separation is on the order of string scale and the occurrence of pair production of open strings when there is a relevant electric flux present. In addition, we have also found many new features of interaction which don't appear in the absence of fluxes or when $p = p'$ in the presence of fluxes, for examples, the nature of interaction can be repulsive and there is no onset of tachyonic instability under certain conditions. Even in the absence of a magnetic flux, we can have an exponential enhancement of the rate of pair production of open strings in certain cases, which may be significant enough to give observational consequences.

  15. Laser beam alignment apparatus and method

    DOE Patents [OSTI]

    Gruhn, Charles R. (Martinez, CA); Hammond, Robert B. (Los Alamos, NM)

    1981-01-01T23:59:59.000Z

    The disclosure relates to an apparatus and method for laser beam alignment. Thermoelectric properties of a disc in a laser beam path are used to provide an indication of beam alignment and/or automatic laser alignment.

  16. Computational Tools for Supersymmetry Calculations

    E-Print Network [OSTI]

    Howard Baer

    2009-12-16T23:59:59.000Z

    I present a brief overview of a variety of computational tools for supersymmetry calculations, including: spectrum generators, cross section and branching fraction calculators, low energy constraints, general purpose event generators, matrix element event generators, SUSY dark matter codes, parameter extraction codes and Les Houches interface tools.

  17. January 1983 / Vol. 8, No. 1 / OPTICS LETTERS 21 Dichroic beam splitter for extreme-ultraviolet and visible

    E-Print Network [OSTI]

    Bokor, Jeffrey

    and UV laser beamsis demonstrated. The devicehas high XUV reflection efficiency(R - 44%)and highdam- age the generatedharmonic inthe XUV. This intense fundamental beam can destroy a sample or saturate detectors of absorbing largeenergy fluxes from pulsed lasers used to generate the XLUV radiation. A typical damage limit

  18. A Comparison of Magnesium and Beryllium Acceptors in GaN Grown by rf-Plasma Assisted Molecular Beam Epitaxy

    E-Print Network [OSTI]

    Myers, Tom

    as a function of substrate temperature and dopant flux for Ga-polarity and N-polarity GaN. Incorporation GaN templates on (0001) sapphire substrates. The doped layers were grown at a rate of 0.25 µmA Comparison of Magnesium and Beryllium Acceptors in GaN Grown by rf-Plasma Assisted Molecular Beam

  19. IRRADIATION CONTROL OF THE "SPIRAL" TARGET BY MEASURING THE ION BEAM INTENSITY VIA A FAST CURRENT TRANSFORMER

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by the target (integrated flux) should not exceed a certain level, function of the radiological risk. In order of measurement will handle the signal of each sensor so that they can be digitized by a computing system received the maximum dose (new safety criterion). PRINCIPLE OF THE MEASUREMENT OF THE BEAM INTENSITY

  20. Production of fullerenes using concentrated solar flux

    DOE Patents [OSTI]

    Fields, Clark L. (Greeley, CO); Pitts, John Roland (Lakewood, CO); King, David E. (Lakewood, CO); Hale, Mary Jane (Golden, CO); Bingham, Carl E. (Denver, CO); Lewandowski, Allan A. (Evergreen, CO)

    2000-01-01T23:59:59.000Z

    A method of producing soot containing high amounts of fullerenes comprising: providing a primary concentrator capable of impingement of a concentrated beam of sunlight onto a carbon source to cause vaporization of carbon and subsequent formation of fullerenes, or providing a solar furnace having a primary concentrator with a focal point that concentrates a solar beam of sunlight; providing a reflective secondary concentrator having an entrance aperture and an exit aperture at the focal point of the solar furnace; providing a carbon source at the exit aperture of the secondary concentrator; supplying an inert gas over the carbon source to keep the secondary concentrator free from vaporized carbon; and impinging a concentrated beam of sunlight from the secondary concentrator on the carbon source to vaporize the carbon source into a soot containing high amounts of fullerenes.

  1. Electrostatic wire stabilizing a charged particle beam

    DOE Patents [OSTI]

    Prono, D.S.; Caporaso, G.J.; Briggs, R.J.

    1983-03-21T23:59:59.000Z

    In combination with a charged particle beam generator and accelerator, apparatus and method are provided for stabilizing a beam of electrically charged particles. A guiding means, disposed within the particle beam, has an electric charge induced upon it by the charged particle beam. Because the sign of the electric charge on the guiding means and the sign of the particle beam are opposite, the particles are attracted toward and cluster around the guiding means to thereby stabilize the particle beam as it travels.

  2. SYNOPTIC MAPPING OF CHROMOSPHERIC MAGNETIC FLUX

    SciTech Connect (OSTI)

    Jin, C. L. [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Harvey, J. W.; Pietarila, A., E-mail: cljin@nao.cas.cn, E-mail: jharvey@nso.edu, E-mail: apietarila@nso.edu [National Solar Observatory, Tucson, AZ 85719 (United States)

    2013-03-10T23:59:59.000Z

    We used daily full-disk Ca II 854.2 nm magnetograms from the Synoptic Optical Long Term Investigations of the Sun (SOLIS) facility to study the chromospheric magnetic field from 2006 April through 2009 November. We determined and corrected previously unidentified zero offsets in the SOLIS magnetograms. By tracking the disk passages of stable unipolar regions, the measured net flux densities were found to systematically decrease from the disk center to the limb by a factor of about two. This decrease was modeled using a thin flux tube model with a difference in signal formation height between the center and limb sides. Comparison of photospheric and chromospheric observations shows that their differences are largely due to horizontal spreading of magnetic flux with increasing height. The north polar magnetic field decreased nearly linearly with time during our study period while the south polar field was nearly constant. We used the annual change in the viewing angle of the polar regions to estimate the radial and meridional components of the polar fields and found that the south polar fields were tilted away from the pole. Synoptic maps of the chromospheric radial flux density distribution were used as boundary conditions for extrapolation of the field from the chromosphere into the corona. A comparison of modeled and observed coronal hole boundaries and coronal streamer positions showed better agreement when using the chromospheric rather than the photospheric synoptic maps.

  3. EUV mirror based absolute incident flux detector

    DOE Patents [OSTI]

    Berger, Kurt W.

    2004-03-23T23:59:59.000Z

    A device for the in-situ monitoring of EUV radiation flux includes an integrated reflective multilayer stack. This device operates on the principle that a finite amount of in-band EUV radiation is transmitted through the entire multilayer stack. This device offers improvements over existing vacuum photo-detector devices since its calibration does not change with surface contamination.

  4. Energies of Quantum QED Flux Tubes

    E-Print Network [OSTI]

    H Weigel

    2006-01-26T23:59:59.000Z

    In this talk I present recent studies on vacuum polarization energies and energy densities induced by QED flux tubes. I focus on comparing three and four dimensional scenarios and the discussion of various approximation schemes in view of the exact treatment.

  5. Flux tubes in the SU(3) vacuum

    E-Print Network [OSTI]

    Mario S. Cardaci; Paolo Cea; Leonardo Cosmai; Rossella Falcone; Alessandro Papa

    2011-09-30T23:59:59.000Z

    We analyze the distribution of the chromoelectric field generated by a static quark-antiquark pair in the SU(3) vacuum. We find that the transverse profile of the flux tube resembles the dual version of the Abrikosov vortex field distribution and give an estimate of the London penetration length in the confined vacuum.

  6. Flux Exclusion Superconducting Quantum Metamaterial: Towards

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Flux Exclusion Superconducting Quantum Metamaterial: Towards Quantum-level Switching V. Savinov1, they require extremely high levels of nanofabrication. Here we introduce a new quantum superconducting properties of the mac- roscopic quantum state of superconducting carriers1 , and essentially plasmonic nature

  7. Orbit and optics improvement by evaluating the nonlinear beam position monitor response in the Cornell Electron Storage Ring

    E-Print Network [OSTI]

    Hoffstaetter, Georg

    by inverting the nonlinear functions, giving us beam position as a function of the pickup signals, and how signals as nonlinear functions of beam position using Greens reciprocity theorem with a two this is also used to improve our calculation of the betatron phase advance. Measurements are presented

  8. Estimated IR and phosphorescence emission fluxes for specific Polycyclic Aromatic Hydrocarbons in the Red Rectangle

    E-Print Network [OSTI]

    G. Mulas; G. Malloci; C. Joblin; D. Toublanc

    2005-09-20T23:59:59.000Z

    Following the tentative identification of the blue luminescence in the Red Rectangle by Vijh et al. (2005), we compute absolute fluxes for the vibrational IR emission and phosphorescence bands of three small polycyclic aromatic hydrocarbons. The calculated IR spectra are compared with available ISO observations. A subset of the emission bands are predicted to be observable using presently available facilities, and can be used for an immediate, independent, discriminating test on their alleged presence in this well-known astronomical object.

  9. High Resolution Muon Computed Tomography at Neutrino Beam Facilities

    E-Print Network [OSTI]

    Burkhant Suerfu; Christopher G. Tully

    2015-01-28T23:59:59.000Z

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pion decay pipe at a neutrino beam facility and what can be achieved for momentum resolution in a muon spectrometer. Such an imaging system can be applied in archaeology, art history, engineering, material identification and whenever there is a need to image inside a transportable object constructed of dense materials.

  10. Melt and vapor characteristics in an electron beam evaporator

    SciTech Connect (OSTI)

    Blumenfeld, L.; Fleche, J.L.; Gonella, C. [DCC/DPE/SPEA Centre d`Etudes de Saclay, Gif-sur-Yvette (France)

    1994-12-31T23:59:59.000Z

    We compare the free surface temperatures T{sub s}, calculated by two methods, in cerium or copper evaporation experiments. The first method considers properties of the melt: by an empirical law we take into account turbulent thermal convection, instabilities and craterization of the free surface. The second method considers the vapor flow expansion and connects T{sub s} to the measured terminal parallel temperature and the terminal mean parallel velocity of the vapor jet, by Direct Simulation Monte Carlo calculations including an atom-atom inelastic collision algorithm. The agreement between the two approaches is better for cerium than for copper in the high craterization case. The analysis, from the point of view of the properties of the melt, of the terminal parameters of the vapor jet for the high beam powers shows that T{sub s} and the Knudsen number at the vapor source reach a threshold when the beam power increases.

  11. Neutral beam heating of a RFP plasma in MST

    SciTech Connect (OSTI)

    Waksman, J.; Anderson, J. K.; Nornberg, M. D.; Parke, E.; Reusch, J. A. [Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706-1390 (United States); Liu, D. [Department of Physics and Astronomy, University of California, Irvine, California 92697-4575 (United States); Fiksel, G. [Laboratory for Laser Energetics, University of Rochester, 250 E. River Rd, Rochester, New York 14623-1299 (United States); Davydenko, V. I.; Ivanov, A. A.; Stupishin, N.; Deichuli, P. P. [Budker Institute of Nuclear Physics, 11, Akademika Lavrentieva Prospect, Novosibirsk 630090 (Russian Federation); Sakakita, H. [National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

    2012-12-15T23:59:59.000Z

    Electron temperature is observed to rise due to neutral beam injection (NBI) in the Madison Symmetric Torus (MST). Heating is observed to be 100 {+-} 50 eV in the core of 200 kA plasmas. This is the first definitive measurement of auxiliary heating of a reversed-field pinch (RFP). This heating is consistent with a 1D classical model which was developed. This 1D model calculates the evolving thermal conductivity and ohmic power input profiles during enhanced confinement, and can calculate NBI deposition and classical fast ion diffusion and slowing. The predicted temperature change is consistent with measured beam heating both during and after enhanced confinement, which is consistent with previous observations that fast ions are well confined and behave roughly classically in the RFP.

  12. Effect of improved target designs on the sup 238 Pu production at the Fast Flux Test Reactor

    SciTech Connect (OSTI)

    Karnesky, R.A.; Wootan, D.W.; Jordheim, D.P. (Westinghouse Hanford Co., Richland, WA (United States))

    1991-11-01T23:59:59.000Z

    This paper present the results of a series of calculations made to determine the {sup 238}Pu production potential of several advanced target assembly designs in the Fast Flux Test Facility (FFTF). These calculations show that by using advanced target designs the intimately mix the {sup 237}Np target material with an yttrium hydride moderator, the FFTF has the potential of producing up to 30 kg of high-quality {sup 238}Pu per year.

  13. Investigation of an electron beam evaporative source: Part 1, Theory; Part 2, Measurements

    SciTech Connect (OSTI)

    Sze, J.S.; Self, S.A. (Lawrence Livermore National Lab., CA (USA))

    1989-09-14T23:59:59.000Z

    A theory for evaluating the performance parameters of linear electron beam evaporative source is presented. The electron beam is considered to be generated from a linear gun and its trajectory is curved by a uniform magnetic field onto a target. A model has been developed to estimate the trajectory of the electron beam. The performance of the electron gun is characterized by two coefficients: {alpha}, the divergence effect of the beam as it enters into the electric field free space region, and {Beta}, the space charge parameter, which is proportional to the magnitude of the current density of the beam. These two parameters determine the location (angular position) of the beam waist and the current density at the target. In addition, neutralization of the electron space charge by vapor ions generated near the target is considered. A discussion is also given of the shape of the depression in the surface of the molten metal, which is due to the pressure on the surface associated with the momentum recoil from the evaporative vapor flux. By relating the characteristic depth and width of the depression to magnitude and the shape of the pressure profile, useful analytical and numerical results are presented for a given pressure profile. The implication of the results for the design of electron beam evaporative sources are also discussed. Measurements are discussed a the end of the paper. 11 refs., 15 figs.

  14. Identifying and bounding uncertainties in nuclear reactor thermal power calculations

    SciTech Connect (OSTI)

    Phillips, J.; Hauser, E.; Estrada, H. [Cameron, 1000 McClaren Woods Drive, Coraopolis, PA 15108 (United States)

    2012-07-01T23:59:59.000Z

    Determination of the thermal power generated in the reactor core of a nuclear power plant is a critical element in the safe and economic operation of the plant. Direct measurement of the reactor core thermal power is made using neutron flux instrumentation; however, this instrumentation requires frequent calibration due to changes in the measured flux caused by fuel burn-up, flux pattern changes, and instrumentation drift. To calibrate the nuclear instruments, steam plant calorimetry, a process of performing a heat balance around the nuclear steam supply system, is used. There are four basic elements involved in the calculation of thermal power based on steam plant calorimetry: The mass flow of the feedwater from the power conversion system, the specific enthalpy of that feedwater, the specific enthalpy of the steam delivered to the power conversion system, and other cycle gains and losses. Of these elements, the accuracy of the feedwater mass flow and the feedwater enthalpy, as determined from its temperature and pressure, are typically the largest contributors to the calorimetric calculation uncertainty. Historically, plants have been required to include a margin of 2% in the calculation of the reactor thermal power for the licensed maximum plant output to account for instrumentation uncertainty. The margin is intended to ensure a cushion between operating power and the power for which safety analyses are performed. Use of approved chordal ultrasonic transit-time technology to make the feedwater flow and temperature measurements (in place of traditional differential-pressure- based instruments and resistance temperature detectors [RTDs]) allows for nuclear plant thermal power calculations accurate to 0.3%-0.4% of plant rated power. This improvement in measurement accuracy has allowed many plant operators in the U.S. and around the world to increase plant power output through Measurement Uncertainty Recapture (MUR) up-rates of up to 1.7% of rated power, while also decreasing the probability of significant over-power events. This paper will examine the basic elements involved in calculation of thermal power using ultrasonic transit-time technology and will discuss the criteria for bounding uncertainties associated with each element in order to achieve reactor thermal power calculations to within 0.3% to 0.4%. (authors)

  15. MEASUREMENT OF BEAM CHARACTERISTICS FOR PHOTO- ELECTRON BEAM...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electron beam is expected to be used in a wide field, such as X-ray generation by inverse Compton scattering, pulse radiolysis, etc. The laser driven photo cathode rf gun system is...

  16. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, J.W.; O`Brien, D.W.

    1996-07-09T23:59:59.000Z

    An apparatus and method are disclosed for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: (1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and (2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1,000 {micro}m (1 mm or larger), compared to the 250 {micro}m diameter of laser drilling. 5 figs.

  17. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, John W. (Pleasanton, CA); O'Brien, Dennis W. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    An apparatus and method for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: 1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and 2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1000 .mu.m (1 mm or larger), compared to the 250 .mu.m diameter of laser drilling.

  18. Alight a beam and beaming light: A theme with variations

    SciTech Connect (OSTI)

    Chattopadhyay, S. [Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, California94720 (United States)] [Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, California94720 (United States)

    1998-05-01T23:59:59.000Z

    The interaction of light (coherent and incoherent) with charged particle beams is explored in various configurations: incoherent scattering of coherent light (laser) from an incoherent particle beam (high temperature), coherent scattering of coherent light (laser) from a {open_quotes}cold{close_quotes} (bunched) beam, femtosecond generation of particle and light beams via {open_quotes}optical slicing{close_quotes} and Thomson/Compton scattering techniques, etc. The domains of ultrashort temporal duration (femtoseconds) as well as ultrashort wavelengths (x rays and shorter), with varying degrees of coherence, are explored. The relevance to a few critical areas of research in the natural sciences, e.g., ultrafast material, chemical and biological processes, protein folding, particle phase space cooling, etc. are touched upon. All the processes discussed involve proper interpretation and understanding of coherent states of matter and radiation, as well as the quality and quantity of information and energy embedded in them. {copyright} {ital 1998 American Institute of Physics.}

  19. Field calculation of D0 toroids and comparison with measurement

    SciTech Connect (OSTI)

    Yamada, R.; Ostiguy, F.; Brzezniak, J.

    1992-06-01T23:59:59.000Z

    The magnetic structure of the D0 detector is described in an earlier report. The two-dimensional code POISSON was used for the initial design of the magnetic structures and the magnetic properties of the D0 toroids. During the construction, the two-dimensional code ANSYS was used to perform more detailed calculations. Full three-dimensional analysis was also performed using the code TOSCA. These new results are reported here and compared with measurements. In this study the magnetic flux in all toroids, CF, EF, and SAMUS is set in the same direction.

  20. Calculation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z C o . C l a r8.0

  1. Thermal stresses in laminated beams

    E-Print Network [OSTI]

    Marcano, Victor Manuel

    1983-01-01T23:59:59.000Z

    Stresses Acting on a Section of the Laminated Beam -------- 15 5. Loading Geometry and Material Characteristics of the Test Problem 21 6. Simply-Supported Beam with a Sinusoidal Load--------- 30 7. Shear Stress Distribution for a Simply- Supported... 24. Normal Stress Distribution for a Cantilever Laminated Beam, T-Z sinzx/L --------------- 58 m. i 25. Axial Stress Distribution for a Cantilever Laminated Bearq, T-T (2z/8+1) 2 mi 27. Normal Stress Distribution for ("/L) ? ---- 6O 2 a...

  2. Thermal stresses in laminated beams 

    E-Print Network [OSTI]

    Marcano, Victor Manuel

    1983-01-01T23:59:59.000Z

    Stresses Acting on a Section of the Laminated Beam -------- 15 5. Loading Geometry and Material Characteristics of the Test Problem 21 6. Simply-Supported Beam with a Sinusoidal Load--------- 30 7. Shear Stress Distribution for a Simply- Supported... 24. Normal Stress Distribution for a Cantilever Laminated Beam, T-Z sinzx/L --------------- 58 m. i 25. Axial Stress Distribution for a Cantilever Laminated Bearq, T-T (2z/8+1) 2 mi 27. Normal Stress Distribution for ("/L) ? ---- 6O 2 a...

  3. Impact of solar EUV flux on CO Cameron band and CO2+ UV doublet emissions in the dayglow of Mars

    E-Print Network [OSTI]

    Jain, Sonal Kumar

    2011-01-01T23:59:59.000Z

    This study is aimed at making a calculation about the impact of the two most commonly used solar EUV flux models -- SOLAR2000 (S2K) of \\cite{Tobiska04} and EUVAC model of \\cite{Richards94} -- on photoelectron fluxes, volume emission rates, ion densities and CO Cameron and CO$_2^+$ UV doublet band dayglow emissions on Mars in three solar activity conditions: minimum, moderate, and maximum. Calculated limb intensities profiles are compared with SPICAM/Mars Express and Mariner observations. Analytical yield spectrum (AYS) approach has been used to calculate photoelectron fluxes in Martian upper atmosphere. Densities of prominent ions and CO molecule in excited triplet a$^3\\Pi$ state are calculated using major ion-neutral reactions. Volume emission rates of CO Cameron and CO$_2^+$ UV doublet bands have been calculated for dif{}ferent observations (Viking condition, Mariner and Mars Express SPICAM observations) on Mars. For the low solar activity condition, dayglow intensities calculated using the S2K model are $\\...

  4. Pressure tensor and heat flux vector for inhomogeneous nonequilibrium fluids under the influence of three-body forces

    E-Print Network [OSTI]

    coupled with the Axilrod-Teller three-body force. Our method of planes calculations agree perfectlyPressure tensor and heat flux vector for inhomogeneous nonequilibrium fluids under the influence of three-body forces Junfang Zhang and B. D. Todd* Centre for Molecular Simulation, Swinburne University

  5. SB EE Calculator | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Calculator Energy Efficiency Decision Support Calculator Argonne's Energy Efficiency Decision Support Calculator is a simple tool that small business owners can use to quickly...

  6. Circular, confined distribution for charged particle beams

    DOE Patents [OSTI]

    Garnett, R.W.; Dobelbower, M.C.

    1995-11-21T23:59:59.000Z

    A charged particle beam line is formed with magnetic optics that manipulate the charged particle beam to form the beam having a generally rectangular configuration to a circular beam cross-section having a uniform particle distribution at a predetermined location. First magnetic optics form a charged particle beam to a generally uniform particle distribution over a square planar area at a known first location. Second magnetic optics receive the charged particle beam with the generally square configuration and affect the charged particle beam to output the charged particle beam with a phase-space distribution effective to fold corner portions of the beam toward the core region of the beam. The beam forms a circular configuration having a generally uniform spatial particle distribution over a target area at a predetermined second location. 26 figs.

  7. Circular, confined distribution for charged particle beams

    DOE Patents [OSTI]

    Garnett, Robert W. (Los Alamos, NM); Dobelbower, M. Christian (Toledo, OH)

    1995-01-01T23:59:59.000Z

    A charged particle beam line is formed with magnetic optics that manipulate the charged particle beam to form the beam having a generally rectangular configuration to a circular beam cross-section having a uniform particle distribution at a predetermined location. First magnetic optics form a charged particle beam to a generally uniform particle distribution over a square planar area at a known first location. Second magnetic optics receive the charged particle beam with the generally square configuration and affect the charged particle beam to output the charged particle beam with a phase-space distribution effective to fold corner portions of the beam toward the core region of the beam. The beam forms a circular configuration having a generally uniform spatial particle distribution over a target area at a predetermined second location.

  8. The effect of nonuniform axial heat flux distribution on the critical heat flux

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01T23:59:59.000Z

    A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

  9. Design of CCD camera system for use inside electron beam furnace

    SciTech Connect (OSTI)

    Sze, J.S.

    1992-10-01T23:59:59.000Z

    The design of a wide dynamic range camera system for use inside Electron Beam furnaces is presented. The camera system is designed for used in high vacuum and in a high radiant heat flux environment looking directly into a high metallic vapor flux. In addition, the camera is designed to have a dynamic range that can provide a good image in both low light level conditions as well as in high brightness situations as when the electron beam impinging on the melt surface. An analysis is given for estimating the dynamic range of the camera imaging system and the camera cooling requirements. Techniques for capturing and recording video images are also presented. The application of various optical filters and liquid crystal variable attenuators for the camera imaging system is discussed.

  10. Confined energy distribution for charged particle beams

    DOE Patents [OSTI]

    Jason, Andrew J. (Los Alamos, NM); Blind, Barbara (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    A charged particle beam is formed to a relatively larger area beam which is well-contained and has a beam area which relatively uniformly deposits energy over a beam target. Linear optics receive an accelerator beam and output a first beam with a first waist defined by a relatively small size in a first dimension normal to a second dimension. Nonlinear optics, such as an octupole magnet, are located about the first waist and output a second beam having a phase-space distribution which folds the beam edges along the second dimension toward the beam core to develop a well-contained beam and a relatively uniform particle intensity across the beam core. The beam may then be expanded along the second dimension to form the uniform ribbon beam at a selected distance from the nonlinear optics. Alternately, the beam may be passed through a second set of nonlinear optics to fold the beam edges in the first dimension. The beam may then be uniformly expanded along the first and second dimensions to form a well-contained, two-dimensional beam for illuminating a two-dimensional target with a relatively uniform energy deposition.

  11. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, H.W.; Hand, S.W. Jr.; Ksayian, H.

    1985-05-31T23:59:59.000Z

    This invention contemplates an armor shield/plasma limiter positioned upon the inner wall of a toroidal vacuum chamber within which is magnetically confined an energetic plasma in a tokamak nuclear fusion reactor. The armor shield/plasma limiter is thus of a general semi-toroidal shape and is comprised of a plurality of adjacent graphite plates positioned immediately adjacent to each other so as to form a continuous ring upon and around the toroidal chamber's inner wall and the reactor's midplane coil. Each plate has a generally semi-circular outer circumference and a recessed inner portion and is comprised of upper and lower half sections positioned immediately adjacent to one another along the midplane of the plate. With the upper and lower half sections thus joined, a channel or duct is provided within the midplane of the plate in which a magnetic flux loop is positioned. The magnetic flux loop is thus positioned immediately adjacent to the fusing toroidal plasma and serves as a diagnostic sensor with the armor shield/plasma limiter minimizing the amount of power from the energetic plasma as well as from the neutral particle beams heating the plasma incident upon the flux loop.

  12. STOCHASTIC COOLING FOR BUNCHED BEAMS.

    SciTech Connect (OSTI)

    BLASKIEWICZ, M.

    2005-05-16T23:59:59.000Z

    Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.

  13. Stability diagram of colliding beams

    E-Print Network [OSTI]

    Buffat, X; Mounet, N; Pieloni, T

    2014-01-01T23:59:59.000Z

    The effect of the beam-beam interactions on the stability of impedance mode is discussed. The detuning is evaluated by the means of single particle tracking in arbitrarily complex collision configurations, including lattice non-linearities, and used to numerically evaluate the dispersion integral. This approach also allows the effect of non-Gaussian distributions to be considered. Distributions modified by the action of external noise are discussed.

  14. Single lens laser beam shaper

    DOE Patents [OSTI]

    Liu, Chuyu (Newport News, VA); Zhang, Shukui (Yorktown, VA)

    2011-10-04T23:59:59.000Z

    A single lens bullet-shaped laser beam shaper capable of redistributing an arbitrary beam profile into any desired output profile comprising a unitary lens comprising: a convex front input surface defining a focal point and a flat output portion at the focal point; and b) a cylindrical core portion having a flat input surface coincident with the flat output portion of the first input portion at the focal point and a convex rear output surface remote from the convex front input surface.

  15. An experimental investigation of a large-flange, thin-web, tapered beam

    E-Print Network [OSTI]

    Duncan, John Van

    1962-01-01T23:59:59.000Z

    Test Procedure 3 5 6 9 10 16 I6 20 V DISCUSSION-EXPERIMENTAL AND THEORETICAL RESULTS Deflectlons Stresses V I CONCLUS I ONS AND RECOMMENDAT I ONS APPEND IX SAMPLE CALCULATIONS Design . Fabrication Loads Web Stresses . Stiffener Design... functions of position on the beam. This suggests an iterative type of Integration for solution. l. owery has programmed Equation 4 for 6 the IBM 709 computer specifically for a three-span overhanging beam. (See Figure &) The results of a thorough design...

  16. An experimental investigation of a large-flange, thin-web, tapered beam 

    E-Print Network [OSTI]

    Duncan, John Van

    1962-01-01T23:59:59.000Z

    Test Procedure 3 5 6 9 10 16 I6 20 V DISCUSSION-EXPERIMENTAL AND THEORETICAL RESULTS Deflectlons Stresses V I CONCLUS I ONS AND RECOMMENDAT I ONS APPEND IX SAMPLE CALCULATIONS Design . Fabrication Loads Web Stresses . Stiffener Design... functions of position on the beam. This suggests an iterative type of Integration for solution. l. owery has programmed Equation 4 for 6 the IBM 709 computer specifically for a three-span overhanging beam. (See Figure &) The results of a thorough design...

  17. Electron beam diagnostic for profiling high power beams

    DOE Patents [OSTI]

    Elmer, John W. (Danville, CA); Palmer, Todd A. (Livermore, CA); Teruya, Alan T. (Livermore, CA)

    2008-03-25T23:59:59.000Z

    A system for characterizing high power electron beams at power levels of 10 kW and above is described. This system is comprised of a slit disk assembly having a multitude of radial slits, a conducting disk with the same number of radial slits located below the slit disk assembly, a Faraday cup assembly located below the conducting disk, and a start-stop target located proximate the slit disk assembly. In order to keep the system from over-heating during use, a heat sink is placed in close proximity to the components discussed above, and an active cooling system, using water, for example, can be integrated into the heat sink. During use, the high power beam is initially directed onto a start-stop target and after reaching its full power is translated around the slit disk assembly, wherein the beam enters the radial slits and the conducting disk radial slits and is detected at the Faraday cup assembly. A trigger probe assembly can also be integrated into the system in order to aid in the determination of the proper orientation of the beam during reconstruction. After passing over each of the slits, the beam is then rapidly translated back to the start-stop target to minimize the amount of time that the high power beam comes in contact with the slit disk assembly. The data obtained by the system is then transferred into a computer system, where a computer tomography algorithm is used to reconstruct the power density distribution of the beam.

  18. Measuring of plasma properties induced by non-vacuum electron beam welding

    SciTech Connect (OSTI)

    Reisgen, U.; Schleser, M.; Abdurakhmanov, A. [RWTH Aachen University ISF-Welding and Joining Institute, 52062 Aachen (Germany); Gumenyuk, A. [BAM Federal Institute for Materials Research and Testing, 12205 Berlin (Germany)

    2012-01-15T23:59:59.000Z

    Electron beam plasma measurement was realised by means of DIABEAM system invented by ISF RWTH Aachen. The Langmuir probe method is used for measurement. The relative simplicity of the method and the possibility of dispersion of high power on the probe allow its application for the investigation of high-power electron beams. The key element of the method is a rotating thin tungsten wire, which intersects the beam transversely on its axis and collects part of the current by itself. The signals, which are registered in the DIABEAM as a voltage, were taken in the form of amplitude. The conversion of the probe current into the distribution along the beam radius was realised using the Abel's method. A voltage-current characteristic was built for the beam current. The local electron density as well as the electron temperature, the floating potential and the plasma potential were measured and calculated by means of this characteristic.

  19. ARM - PI Product - Radiative Flux Analysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheatProductsISDACProductsRadiative Flux Analysis ARM

  20. KTeV beam systems design report

    SciTech Connect (OSTI)

    Bocean, V.; Childress, S.; Coleman, R. [and others

    1997-09-01T23:59:59.000Z

    The primary and secondary beams for the KTeV experiments E799-II and E832 are discussed. The specifications are presented and justified. The technical details of the implementation of the primary beam transport and stability are detailed. The target, beam dump, and radiation safety issues are discussed. The details of the collimation system for the pair of secondary beams are presented.

  1. Neutron/gamma coupled library generation and gamma transport calculation with KARMA 1.2

    SciTech Connect (OSTI)

    Hong, S. G. [Dept. of Nuclear Engineering, Kyung Hee Univ., 446-701 Deogyeong-daero, GiHeung-gu, Yongin, Gyeonggi-do (Korea, Republic of); Kim, K. S.; Cho, J. Y.; Lee, K. H. [Korea Atomic Energy Research Inst., 305-353 Duckjin-dong, Yuseong-gu, Daejon (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    KAERI has developed a lattice transport calculation code KARMA and its multi-group cross section library generation system. Recently, the multi-group cross section library generation system has included a gamma cross section generation capability and KARMA also has been improved to include a gamma transport calculation module. This paper addresses the multi-group gamma cross section generation capability for the KARMA 1.2 code and the preliminary test results of the KARMA 1.2 gamma transport calculations. The gamma transport calculation with KARMA 1.2 gives the gamma flux, gamma smeared power, and gamma energy deposition distributions. The results of the KARMA gamma calculations were compared with those of HELIOS and they showed that KARMA 1.2 gives reasonable gamma transport calculation results. (authors)

  2. Surface Magnetic Flux Maintenance In Quiet Sun

    E-Print Network [OSTI]

    Y. Iida

    2012-12-27T23:59:59.000Z

    We investigate surface processes of magnetic patches, namely merging, splitting, emergence, and cancellation, by using an auto-detection technique. We find that merging and splitting are locally predominant in the surface level, while the frequencies of the other two are less by one or two orders of magnitude. The frequency dependences on flux con- tent of surface processes are further investigated. Based on these observations, we discuss a possible whole picture of the maintenance. Our conclusion is that the photospheric magnetic field structure, especially its power-law nature, is maintained by the processes locally in the surface not by the interactions between different altitudes. We suggest a scenario of the flux maintenance as follows: The splitting and merging play a crucial role for the generation of the power-law distribution, not the emergence nor cancellation do. This power-law distribution results in another power-law one of the cancellation with an idea of the random convective transport. The cancellation and emergence have a common value for the power-law indices in their frequency distributions, which may suggest a "recycle of fluxes by submergence and re-emergence".

  3. Coupling spin ensembles via superconducting flux qubits

    E-Print Network [OSTI]

    Yueyin Qiu; Wei Xiong; Lin Tian; J. Q. You

    2014-09-10T23:59:59.000Z

    We study a hybrid quantum system consisting of spin ensembles and superconducting flux qubits, where each spin ensemble is realized using the nitrogen-vacancy centers in a diamond crystal and the nearest-neighbor spin ensembles are effectively coupled via a flux qubit.We show that the coupling strengths between flux qubits and spin ensembles can reach the strong and even ultrastrong coupling regimes by either engineering the hybrid structure in advance or tuning the excitation frequencies of spin ensembles via external magnetic fields. When extending the hybrid structure to an array with equal coupling strengths, we find that in the strong-coupling regime, the hybrid array is reduced to a tight-binding model of a one-dimensional bosonic lattice. In the ultrastrong-coupling regime, it exhibits quasiparticle excitations separated from the ground state by an energy gap. Moreover, these quasiparticle excitations and the ground state are stable under a certain condition that is tunable via the external magnetic field. This may provide an experimentally accessible method to probe the instability of the system.

  4. Proton induced activation in mercury: Comparison of measurements and calculations

    SciTech Connect (OSTI)

    Remec, Igor [ORNL; Glasgow, David C [ORNL; Haines, John R [ORNL; Johnson, Jeffrey O [ORNL

    2008-01-01T23:59:59.000Z

    Measurements and simulations of the proton beam interaction with the mercury target were performed to support Spallation Neutron Source design. Due to the abundance of isotopes produced in mercury, the long delay between the irradiation and the measurements, and the self-shielding of the mercury sample, the measurements were difficult to perform and the activities of several isotopes have large uncertainties. Calculations predicted the activities of the most reliably measured isotopes within 20%/40%; however, some large discrepancies were observed for some isotopes for which the measurements were considered less reliable. Predicted dose rates were in very good agreement with the measurements.

  5. Experimental and numerical study of e-beam evaporation of titanium

    SciTech Connect (OSTI)

    McClelland, M.A.; Westerberg, K.W.; Meier, T.C. [Lawrence Livermore National Lab., CA (United States)] [and others

    1996-12-31T23:59:59.000Z

    An experimental and numerical study is performed for the electron-beam evaporation of pure titanium from a bottom fed vapor source. In the experiments, an electron beam operating in the nominal range of 30-40 [kW] was used to evaporate metal from the top of a 3 [in] diameter rod. Variations were made in the e-beam power, sweep pattern, and sweep frequency, and the total evaporation rate was measured from feed consumption and laser absorption. The solid-pool interface was obtained from metallographic cross sections of the metal rod. A two-dimensional finite element model was developed for the melt which includes the effect of fluid flow and energy transport in the pool and conduction in the solid. The deformation of the liquid-vapor and solid-liquid interfaces are tracked using a mesh which stretches along spines parallel to the axis of the rod. For the cases considered, high evaporative fluxes and vapor pressures generate significant depressions in the top surface of the pool. Predicted and measured evaporation rates are in good agreement for moderate evaporation fluxes, but discrepancies are larger for the case involving the highest flux and deepest depression.

  6. Experimental and numerical study of E-beam evaporation of titanium

    SciTech Connect (OSTI)

    McClelland, M.A.; Westerberg, K.W.; Meier, T.C.; Braun, D.G.; Berrins, L.V.; Anklam, T.M. Storer, J.

    1997-11-26T23:59:59.000Z

    An experimental and numerical study is performed for the electron- beam evaporation of pure titanium from a bottom fed vapor source. In the experiments, an electron beam operating in the nominal range of 30-40 [kW] was used to evaporate metal from the top of a 3 inch diameter rod. Variations were made in the e-beam power, sweep pattern, and sweep frequency, and the total evaporation rate was measured from feed consumption and laser absorption. The solid-pool interface was obtained from metallographic cross sections of the metal rod. A two-dimensional finite element model was developed for the melt which includes the effect of fluid flow and energy transport in the pool and conduction in the solid. The deformation of the liquid-vapor and solid-liquid interfaces are tracked using a mesh which stretches along spines parallel to the axis of the rod. For the cases considered, high evaporative fluxes and vapor pressures generate significant depressions in the top surface of the pool. Predicted and measured evaporation rates are in good agreement for moderate evaporation fluxes, but discrepancies are larger for the case involving the highest flux and deepest depression.

  7. High Flux Isotope Reactor named Nuclear Historic Landmark | ornl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    High Flux Isotope Reactor named Nuclear Historic Landmark The High Flux Isotope Reactor vessel at Oak Ridge National Laboratory resides in a pool of water illuminated by the blue...

  8. Head-on beam-beam tune shifts with high brightness beams in the LHC

    E-Print Network [OSTI]

    Alemany, R; Calaga, R; Cornelis, K; Fitterer, M; Giachino, R; Herr, W; McPherson, A; Miyamoto, R; Papotti, G; Pieloni, T; Redaelli, S; Roncarolo, F; Schaumann, M; Suykerbuyk, R; Trad, G; Paret, S

    2011-01-01T23:59:59.000Z

    In this experiment (fills 1765, 1766) we have collided bunches with highest brightness, i.e. small emittances and high intensities, to explore the achievable beam-beam tune shift for head-on collisions. Different parameters and filling schemes have been used for this experiment and tune shifts above 0.015 have been achieved in single collisions and above 0.030 for two collision points.

  9. eRHIC ring-ring design with head-on beam-beam compensation

    SciTech Connect (OSTI)

    Montag,C.; Blaskiewicz, M.; Pozdeyev, E.; Fischer, W.; MacKay, W. W.

    2009-05-04T23:59:59.000Z

    The luminosity of the eRHIC ring-ring design is limited by the beam-beam effect exerted on the electron beam. Recent simulation studies have shown that the beam-beam limit can be increased by means of an electron lens that compensates the beam-beam effect experienced by the electron beam. This scheme requires proper design of the electron ring, providing the correct betatron phase advance between interaction point and electron lens. We review the performance of the eRHIC ring-ring version and discuss various parameter sets, based on different cooling schemes for the proton/ion beam.

  10. Commissioning of output factors for uniform scanning proton beams

    SciTech Connect (OSTI)

    Zheng Yuanshui; Ramirez, Eric; Mascia, Anthony; Ding Xiaoning; Okoth, Benny; Zeidan, Omar; Hsi Wen; Harris, Ben; Schreuder, Andries N.; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

    2011-04-15T23:59:59.000Z

    Purpose: Current commercial treatment planning systems are not able to accurately predict output factors and calculate monitor units for proton fields. Patient-specific field output factors are thus determined by either measurements or empirical modeling based on commissioning data. The objective of this study is to commission output factors for uniform scanning beams utilized at the ProCure proton therapy centers. Methods: Using water phantoms and a plane parallel ionization chamber, the authors first measured output factors with a fixed 10 cm diameter aperture as a function of proton range and modulation width for clinically available proton beams with ranges between 4 and 31.5 cm and modulation widths between 2 and 15 cm. The authors then measured the output factor as a function of collimated field size at various calibration depths for proton beams of various ranges and modulation widths. The authors further examined the dependence of the output factor on the scanning area (i.e., uncollimated proton field), snout position, and phantom material. An empirical model was developed to calculate the output factor for patient-specific fields and the model-predicted output factors were compared to measurements. Results: The output factor increased with proton range and field size, and decreased with modulation width. The scanning area and snout position have a small but non-negligible effect on the output factors. The predicted output factors based on the empirical modeling agreed within 2% of measurements for all prostate treatment fields and within 3% for 98.5% of all treatment fields. Conclusions: Comprehensive measurements at a large subset of available beam conditions are needed to commission output factors for proton therapy beams. The empirical modeling agrees well with the measured output factor data. This investigation indicates that it is possible to accurately predict output factors and thus eliminate or reduce time-consuming patient-specific output measurements for proton treatments.

  11. Nufact 2008 The Beta Beam WP Beta beam R&D status

    E-Print Network [OSTI]

    McDonald, Kirk

    Nufact 2008 The Beta Beam WP Nufact 08 1 Beta beam R&D status Elena Wildner, CERN on behalf of the Beta Beam Study Group EURISOL/Euronu #12;Nufact 2008 The Beta Beam WP Nufact08Nufact08 Outline Recall, EURISOL Ion Production Loss Management Improvements New Program, EuroNu 2 #12;Nufact 2008 The Beta Beam WP

  12. Energy deposition in t in films calculated using ellectron transport theory Theodore Biewer and Peter Rez

    E-Print Network [OSTI]

    Biewer, Theodore

    Energy deposition in t in films calculated using ellectron transport theory Theodore Biewer damage which can be related to the energy deposited in the specimen. We derive an expression for the energy deposition using the electron transport equation and give results for beam energies of l-10 k

  13. D-Cluster Converter Foil for Laser-Accelerated Deuteron Beams: Towards Deuteron-Beam-Driven Fast Ignition

    SciTech Connect (OSTI)

    Miley, George H.

    2012-10-24T23:59:59.000Z

    Fast Ignition (FI) uses Petawatt laser generated particle beam pulse to ignite a small volume called a pre-compressed Inertial Confinement Fusion (ICF) target, and is the favored method to achieve the high energy gain per target burn needed for an attractive ICF power plant. Ion beams such as protons, deuterons or heavier carbon ions are especially appealing for FI as they have relative straight trajectory, and easier to focus on the fuel capsule. But current experiments have encountered problems with the 'converter-foil' which is irradiated by the Petawatt laser to produce the ion beams. The problems include depletion of the available ions in the convertor foils, and poor energy efficiency (ion beam energy/ input laser energy). We proposed to develop a volumetrically-loaded ultra-high-density deuteron deuterium cluster material as the basis for converter-foil for deuteron beam generation. The deuterons will fuse with the ICF DT while they slow down, providing an extra 'bonus' energy gain in addition to heating the hot spot. Also, due to the volumetric loading, the foil will provide sufficient energetic deuteron beam flux for 'hot spot' ignition, while avoiding the depletion problem encountered by current proton-driven FI foils. After extensive comparative studies, in Phase I, high purity PdO/Pd/PdO foils were selected for the high packing fraction D-Cluster converter foils. An optimized loading process has been developed to increase the cluster packing fraction in this type of foil. As a result, the packing fraction has been increased from 0.1% to 10% - meeting the original Phase I goal and representing a significant progress towards the beam intensities needed for both FI and pulsed neutron applications. Fast Ignition provides a promising approach to achieve high energy gain target performance needed for commercial Inertial Confinement Fusion (ICF). This is now a realistic goal for near term in view of the anticipated ICF target burn at the National Ignition Facility (NIF) in CA within a year. This will usher in the technology development Phase of ICF after years of research aimed at achieving breakeven experiment. Methods to achieve the high energy gain needed for a competitive power plant will then be a key developmental issue, and our D-cluster target for Fast Ignition (FI) is expected to meet that need.

  14. Spheromak reactor with poloidal flux-amplifying transformer

    DOE Patents [OSTI]

    Furth, Harold P. (Princeton, NJ); Janos, Alan C. (East Windsor, NJ); Uyama, Tadao (Osaka, JP); Yamada, Masaaki (Lawrenceville, NJ)

    1987-01-01T23:59:59.000Z

    An inductive transformer in the form of a solenoidal coils aligned along the major axis of a flux core induces poloidal flux along the flux core's axis. The current in the solenoidal coil is then reversed resulting in a poloidal flux swing and the conversion of a portion of the poloidal flux to a toroidal flux in generating a spheromak plasma wherein equilibrium approaches a force-free, minimum Taylor state during plasma formation, independent of the initial conditions or details of the formation. The spheromak plasma is sustained with the Taylor state maintained by oscillating the currents in the poloidal and toroidal field coils within the plasma-forming flux core. The poloidal flux transformer may be used either as an amplifier stage in a moving plasma reactor scenario for initial production of a spheromak plasma or as a method for sustaining a stationary plasma and further heating it. The solenoidal coil embodiment of the poloidal flux transformer can alternately be used in combination with a center conductive cylinder aligned along the length and outside of the solenoidal coil. This poloidal flux-amplifying inductive transformer approach allows for a relaxation of demanding current carrying requirements on the spheromak reactor's flux core, reduces plasma contamination arising from high voltage electrode discharge, and improves the efficiency of poloidal flux injection.

  15. Analysis and results of a hydrogen moderated isotope production assembly in the Fast Flux Test Facility

    SciTech Connect (OSTI)

    Wootan, D.W.; Rawlins, J.A.; Carter, L.L.; Brager, H.R.; Schenter, R.E.

    1988-06-01T23:59:59.000Z

    A cobalt test assembly containing yttrium hydride pins for neutron moderation was irradiated in the Fast Flux Test Facility during Cycle 9A for 137.7 equivalent full-power days at a power level of 291 MW. The 36 test pins consisted of a batch of 32 pins containing cobalt metal used to produce /sup 60/Co and a set of four pins with europium oxide to produce /sup 153/Gd, a radioisotope used in detection of the bone disease osteoporosis. Postirradiation examination of the cobalt pins determined the /sup 60/Co was produced with an accuracy of about 5%. The measured /sup 60/Co spatially distributed concentrations were within 20% of the calculated concentrations. The assembly average /sup 60/Co measured activity was 4% less than the calculated value. The europium oxide pins were gamma scanned for the europium isotopes /sup 152/Eu and /sup 154/Eu to an absolute accuracy of about 10%. The measured europium radioisotope and /sup 153/Gd concentrations were within 20% of calculated values. The hydride assembly performed well and is an excellent vehicle for many Fast Flux Test Facility isotope production applications. The results also demonstrate the accuracy of the calculational methods developed by the Westinghouse Hanford Company for predicting isotope production rates in this type of assembly. 4 refs., 5 figs., 2 tabs.

  16. Generate Uniform Transverse Distributed Electron Beam along a Beam Line

    E-Print Network [OSTI]

    Jiao, Y

    2015-01-01T23:59:59.000Z

    It has been reported that transverse distribution shaping can help to further enhance the energy extraction efficiency in a terawatt, tapered X-ray free-electron laser. Thus, methods of creating and keeping almost uniform transverse distributed (UTD) beam within undulators are required. This study shows that a UTD electron beam can be generated within evenly distributed drift sections where undulators can be placed, by means of octupoles and particular optics. A concrete design is presented, and numerical simulations are done to verify the proposed method.

  17. The Role and Detectability of the Charm Contribution to Ultra High Energy Neutrino Fluxes

    E-Print Network [OSTI]

    Gandhi, Raj; Watanabe, Atsushi

    2009-01-01T23:59:59.000Z

    It is widely believed that charm meson production and decay may play an important role in high energy astrophysical sources of neutrinos, especially those that are baryon-rich, providing an environment conducive to pp interactions. Using slow-jet supernovae (SJS) as an example of such a source, we study the detectability of high-energy neutrinos, paying particular attention to those produced from charmed-mesons. We highlight important distinguishing features in the ultra-high energy neutrino flux which would act as markers for the role of charm in the source. In particular, charm leads to significant event rates at higher energies, after the conventional (pi, K) neutrino fluxes fall off. We calculate event rates both for a nearby single source and for diffuse SJS fluxes for an IceCube-like detector. By comparing muon event rates for the conventional and prompt fluxes in different energy bins, we demonstrate the striking energy dependence in the rates induced by the presence of charm. We also show that it lead...

  18. Channeling Effect in Polycrystalline Deuterium-Saturated CVD Diamond Target Bombarded by Deuterium Ion Beam

    E-Print Network [OSTI]

    Bagulya, A V; Negodaev, M A; Rusetskii, A S; Chubenko, A P; Ralchenko, V G; Bolshakov, A P

    2014-01-01T23:59:59.000Z

    At the ion accelerator HELIS at the LPI, the neutron yield is investigated in DD reactions within a polycrystalline deuterium-saturated CVD diamond, during an irradiation of its surface by a deuterium ion beam with the energy less than 30 keV. The measurements of the neutron flux in the beam direction are performed in dependence on the target angle, \\b{eta}, with respect to the beam axis. These measurements are performed using a multichannel detector based on He3 counters. A significant anisotropy in neutron yield is observed, it was higher by a factor of 3 at \\b{eta}=0 compared to that at \\b{eta} = +-45{\\deg}. The possible reasons for the anisotropy, including ion channeling, are discussed.

  19. Channeling Effect in Polycrystalline Deuterium-Saturated CVD Diamond Target Bombarded by Deuterium Ion Beam

    E-Print Network [OSTI]

    A. V. Bagulya; O. D. Dalkarov; M. A. Negodaev; A. S. Rusetskii; A. P. Chubenko; V. G. Ralchenko; A. P. Bolshakov

    2014-09-08T23:59:59.000Z

    At the ion accelerator HELIS at the LPI, the neutron yield is investigated in DD reactions within a polycrystalline deuterium-saturated CVD diamond, during an irradiation of its surface by a deuterium ion beam with the energy less than 30 keV. The measurements of the neutron flux in the beam direction are performed in dependence on the target angle, \\b{eta}, with respect to the beam axis. These measurements are performed using a multichannel detector based on He3 counters. A significant anisotropy in neutron yield is observed, it was higher by a factor of 3 at \\b{eta}=0 compared to that at \\b{eta} = +-45{\\deg}. The possible reasons for the anisotropy, including ion channeling, are discussed.

  20. Diamond pixel detector for beam profile monitoring in COMET experiment at J-PARC

    E-Print Network [OSTI]

    M. Cerv; P. Sarin; H. Pernegger; P. Vageesvaran; E. Griesmayer

    2014-11-15T23:59:59.000Z

    We present the design and initial prototype results of a pixellized proton beam profile monitor for the COMET experiment at J-PARC. The goal of COMET is to look for charged lepton flavor violation by direct muon to electron conversion at a sensitivity of $0^{-19}$. An 8 GeV proton beam pulsed at 100 ns with $10^{10}$ protons/s will be used to create muons through pion production and decay. In the final experiment, the proton flux will be raised to $10^{14}$ protons/sec to increase the sensitivity. These requirements of harsh radiation tolerance and fast readout make diamond a good choice for constructing a beam profile monitor in COMET. We present first results of the characterization of single crystal diamond (scCVD) sourced from a new company, 2a systems Singapore. Our measurements indicate excellent charge collection efficiency and high carrier mobility down to cryogenic temperatures.

  1. On the Sensitivity of ?/? Prediction to Dose Calculation Methodology in Prostate Brachytherapy

    SciTech Connect (OSTI)

    Afsharpour, Hossein [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada); Centre Intégré de Cancérologie de la Montérégie, Hôpital Charles-LeMoyne, Greenfield Park, QC (Canada); Walsh, Sean [Department of Radiation Oncology Maastricht Radiation Oncology (MAASTRO), GROW, University Hospital Maastricht, Maastricht (Netherlands); Gray Institute for Radiation Oncology and Biology, The University of Oxford, The United Kingdom (United Kingdom); Collins Fekete, Charles-Antoine; Vigneault, Eric [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada); Verhaegen, Frank [Department of Radiation Oncology Maastricht Radiation Oncology (MAASTRO), GROW, University Hospital Maastricht, Maastricht (Netherlands); Medical Physics Unit, Department of Oncology, McGill University, Montréal, Québec (Canada); Beaulieu, Luc, E-mail: Luc.Beaulieu@phy.ulaval.ca [Centre de Recherche sur le Cancer, Université Laval and Département de Radio-Oncologie, Centre Hospitalier Universitaire de Québec, Québec, QC (Canada)

    2014-02-01T23:59:59.000Z

    Purpose: To study the relationship between the accuracy of the dose calculation in brachytherapy and the estimations of the radiosensitivity parameter, ?/?, for prostate cancer. Methods and Materials: In this study, Monte Carlo methods and more specifically the code ALGEBRA was used to produce accurate dose calculations in the case of prostate brachytherapy. Equivalent uniform biologically effective dose was calculated for these dose distributions and was used in an iso-effectiveness relationship with external beam radiation therapy. Results: By considering different levels of detail in the calculations, the estimation for the ?/? parameter varied from 1.9 to 6.3 Gy, compared with a value of 3.0 Gy suggested by the American Association of Physicists in Medicine Task Group 137. Conclusions: Large variations of the ?/? show the sensitivity of this parameter to dose calculation modality. The use of accurate dose calculation engines is critical for better evaluating the biological outcomes of treatments.

  2. The neutrino signal at HALO: learning about the primary supernova neutrino fluxes and neutrino properties

    SciTech Connect (OSTI)

    Väänänen, Daavid; Volpe, Cristina, E-mail: vaananen@ipno.in2p3.fr, E-mail: volpe@ipno.in2p3.fr [Institut de Physique Nucléaire, F-91406 Orsay cedex, CNRS/IN2P3 and University of Paris-XI (France)

    2011-10-01T23:59:59.000Z

    Core-collapse supernova neutrinos undergo a variety of phenomena when they travel from the high neutrino density region and large matter densities to the Earth. We perform analytical calculations of the supernova neutrino fluxes including collective effects due to the neutrino-neutrino interactions, the Mikheev-Smirnov-Wolfenstein (MSW) effect due to the neutrino interactions with the background matter and decoherence of the wave packets as they propagate in space. We predict the numbers of one- and two-neutron charged and neutral-current electron-neutrino scattering on lead events. We show that, due to the energy thresholds, the ratios of one- to two-neutron events are sensitive to the pinching parameters of neutrino fluxes at the neutrinosphere, almost independently of the presently unknown neutrino properties. Besides, such events have an interesting sensitivity to the spectral split features that depend upon the presence/absence of energy equipartition among neutrino flavors. Our calculations show that a lead-based observatory like the Helium And Lead Observatory (HALO) has the potential to pin down important characteristics of the neutrino fluxes at the neutrinosphere, and provide us with information on the neutrino transport in the supernova core.

  3. Monte Carlo calculations of nuclei

    SciTech Connect (OSTI)

    Pieper, S.C. [Argonne National Lab., IL (United States). Physics Div.

    1997-10-01T23:59:59.000Z

    Nuclear many-body calculations have the complication of strong spin- and isospin-dependent potentials. In these lectures the author discusses the variational and Green`s function Monte Carlo techniques that have been developed to address this complication, and presents a few results.

  4. AmeriFlux Network Data from the ORNL AmeriFlux Website

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The AmeriFlux network was established in 1996 to provide continuous observations of ecosystem level exchanges of CO2, water, energy and momentum spanning diurnal, synoptic, seasonal, and interannual time scales. It is fed by sites from North America, Central America, and South America. DOE's CDIAC stores and maintains AmeriFlux data, and this web site explains the different levels of data available there, with links to the CDIAC ftp site. A separate web-based data interface is also provided; it allows users to graph, query, and download Level 2 data for up to four sites at a time. Data may be queried by site, measurement period, or parameter. More than 550 site-years of level 2 data are available from AmeriFlux sites through the interface.

  5. Physics Opportunities with Meson Beams

    E-Print Network [OSTI]

    Briscoe, William J; Haberzettl, Helmut; Manley, D Mark; Naruki, Megumi; Strakovsky, Igor I; Swanson, Eric S

    2015-01-01T23:59:59.000Z

    Over the past two decades, meson photo- and electro-production data of unprecedented quality and quantity have been measured at electromagnetic facilities worldwide. By contrast, the meson-beam data for the same hadronic final states are mostly outdated and largely of poor quality, or even nonexistent, and thus provide inadequate input to help interpret, analyze, and exploit the full potential of the new electromagnetic data. To reap the full benefit of the high-precision electromagnetic data, new high-statistics data from measurements with meson beams, with good angle and energy coverage for a wide range of reactions, are critically needed to advance our knowledge in baryon and meson spectroscopy and other related areas of hadron physics. To address this situation, a state of-the-art meson-beam facility needs to be constructed. The present paper summarizes unresolved issues in hadron physics and outlines the vast opportunities and advances that only become possible with such a facility.

  6. Divergence of optical vortex beams

    E-Print Network [OSTI]

    Reddy, Salla Gangi; Prabhakar, Shashi; Anwar, Ali; Banerji, J; Singh, R P

    2015-01-01T23:59:59.000Z

    We show, both theoretically and experimentally, that the propagation of optical vortices in free space can be analysed by using the width ($w(z)$) of the host Gaussian beam and the inner and outer radii of the vortex beam at the source plane ($z=0$) as defined in \\textit{Optics Letters \\textbf{39,} 4364-4367 (2014)}. We also studied the divergence of vortex beams, considered as the rate of change of inner or outer radius with the propagation distance, and found that it varies with the order in the same way as that of the inner and outer radii at zero propagation distance. These results may be useful in designing optical fibers for orbital angular momentum modes that play a crucial role in quantum communication.

  7. CO2 CH4 flux Air temperature Soil temperature and Soil moisture, Barrow, Alaska 2013 ver. 1

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Margaret Torn

    This dataset consists of field measurements of CO2 and CH4 flux, as well as soil properties made during 2013 in Areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Included are i) measurements of CO2 and CH4 flux made from June to September (ii) Calculation of corresponding Gross Primary Productivity (GPP) and CH4 exchange (transparent minus opaque) between atmosphere and the ecosystem (ii) Measurements of Los Gatos Research (LGR) chamber air temperature made from June to September (ii) measurements of surface layer depth, type of surface layer, soil temperature and soil moisture from June to September.

  8. Measurement of the curvature of a surface using parallel light beams

    DOE Patents [OSTI]

    Chason, E.H.; Floro, J.A.; Seager, C.H.; Sinclair, M.B.

    1999-06-15T23:59:59.000Z

    Apparatus is disclosed for measuring curvature of a surface wherein a beam of collimated light is passed through a means for producing a plurality of parallel light beams each separated by a common distance which then reflect off the surface to fall upon a detector that measures the separation of the reflected beams of light. This means can be an etalon and the combination of a diffractive element and a converging lens. The curvature of the surface along the line onto which the multiple beams fall can be calculated from this information. A two-dimensional map of the curvature can be obtained by adding a second etalon (or a second combination of a diffractive element and a converging lens) which is rotated 90[degree] about the optical axis relative to the first etalon and inclined at the same angle. The second etalon creates an individual set of parallel light beams from each of the individual beams created by the first etalon with the sets of parallel light beams from the second etalon rotated 90[degree] relative to the line onto which the single set of parallel beams from the first etalon would have fallen. 5 figs.

  9. Measurement of the curvature of a surface using parallel light beams

    DOE Patents [OSTI]

    Chason, Eric H. (Sandia Park, NM); Floro, Jerrold A. (Edgewood, NM); Seager, Carleton H. (Albuquerque, NM); Sinclair, Michael B. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    Apparatus for measuring curvature of a surface wherein a beam of collimated light is passed through means for producing a plurality of parallel light beams each separated by a common distance which then reflect off the surface to fall upon a detector that measures the separation of the reflected beams of light. This means can be an etalon and the combination of a diffractive element and a converging lens. The curvature of the surface along the line onto which the multiple beams fall can be calculated from this information. A two-dimensional map of the curvature can be obtained by adding a second etalon (or a second combination of a diffractive element and a converging lens) which is rotated 90.degree. about the optical axis relative to the first etalon and inclined at the same angle. The second etalon creates an individual set of parallel light beams from each of the individual beams created by the first etalon with the sets of parallel light beams from the second etalon rotated 90.degree. relative to the line onto which the single set of parallel beams from the first etalon would have fallen.

  10. The effect of anterior proton beams in the setting of a prostate-rectum spacer

    SciTech Connect (OSTI)

    Christodouleas, John P., E-mail: christojo@uphs.upenn.edu [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Tang, Shikui [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Susil, Robert C.; McNutt, Todd R.; Song, Danny Y. [Department of Radiation Oncology and Radiation Molecular Sciences, Johns Hopkins Hospital, Baltimore, MD (United States); Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); DeWeese, Theodore L. [Department of Radiation Oncology and Radiation Molecular Sciences, Johns Hopkins Hospital, Baltimore, MD (United States); Lu, Hsiao-Ming [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Both, Stefan [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States)

    2013-10-01T23:59:59.000Z

    Studies suggest that anterior beams with in vivo range verification would improve rectal dosimetry in proton therapy for prostate cancer. We investigated whether prostate-rectum spacers would enhance or diminish the benefits of anterior proton beams in these treatments. Twenty milliliters of hydrogel was injected between the prostate and rectum of a cadaver using a transperineal approach. Computed tomography (CT) and magnetic resonance (MR) images were used to generate 7 uniform scanning (US) and 7 single-field uniform dose pencil-beam scanning (PBS) plans with different beam arrangements. Pearson correlations were calculated between rectal, bladder, and femoral head dosimetric outcomes and beam arrangement anterior scores, which characterize the degree to which dose is delivered anteriorly. The overall quality of each plan was compared using a virtual dose-escalation study. For US plans, rectal mean dose was inversely correlated with anterior score, but for PBS plans there was no association between rectal mean dose and anterior score. For both US and PBS plans, full bladder and empty bladder mean doses were correlated with anterior scores. For both US and PBS plans, femoral head mean doses were inversely correlated with anterior score. For US plans and a full bladder, 4 beam arrangements that included an anterior beam tied for the highest maximum prescription dose (MPD). For US plans and an empty bladder, the arrangement with 1 anterior and 2 anterior oblique beams achieved the highest MPD in the virtual dose-escalation study. The dose-escalation study did not differentiate beam arrangements for PBS. All arrangements in the dose-escalation study were limited by bladder constraints except for the arrangement with 2 posterior oblique beams. The benefits of anterior proton beams in the setting of prostate-rectum spacers appear to be proton modality dependent and may not extend to PBS.

  11. SU(2) Flux Distributions on Finite Lattices

    E-Print Network [OSTI]

    Peng, Y; Peng, Yingcai; Haymaker, Richard W.

    1993-01-01T23:59:59.000Z

    We studied SU(2) flux distributions on four dimensional euclidean lattices with one dimension very large. By choosing the time direction appropriately we can study physics in two cases: one is finite volume in the zero temperature limit, another is finite temperature in the the intermediate to large volume limit. We found that for cases of beta > beta crit there is no intrinsic string formation. Our lattices with beta > beta crit belong to intermediate volume region, and the string tension in this region is due to finite volume effects. In large volumes we found evidence for intrinsic string formation.

  12. Semiconducting glasses with flux pinning inclusions

    DOE Patents [OSTI]

    Johnson, William L. (Pasadena, CA); Poon, Siu-Joe (Palo Alto, CA); Duwez, Pol E. (Pasadena, CA)

    1981-01-01T23:59:59.000Z

    A series of amorphous superconducting glassy alloys containing 1% to 10% by volume of flux pinning crystalline inclusions have been found to have potentially useful properties as high field superconducting magnet materials. The alloys are prepared by splat cooling by the piston and anvil technique. The alloys have the composition (TM).sub.90-70 (M).sub.10-30 where TM is a transition metal selected from at least one metal of Groups IVB, VB, VIB, VIIB or VIIIB of the Periodic Table such as Nb, Mo, Ru, Zr, Ta, W or Re and M is at least one metalloid such as B, P, C, N, Si, Ge or Al.

  13. Resonant absorption in dissipative flux tubes

    E-Print Network [OSTI]

    Safari, H; Karami, K; Sobouti, Y

    2005-01-01T23:59:59.000Z

    Oscillations of coronal loops are believed to be the primary cause of the solar corona heating. We study the resonant absorbtion of MHD waves in magnetized flux tubes with graded densities across the cross section of the tube. Within the approximation that resistive and viscous processes are operative in thin layers surrounding the singularities of the MHD equations, we give the full spectrum of the eigenfrequencies, damping rates, as well as, the eigenfields of the normal MHD modes of the tube. Both surface and body modes are analyzed and the contribution of each class to heating of the corona is commented on.

  14. Cosmic-ray Muon Flux In Belgrade

    SciTech Connect (OSTI)

    Banjanac, R.; Dragic, A.; Jokovic, D.; Udovicic, V. [Institute of Physics, University of Belgrade, Belgrade (Serbia and Montenegro); Puzovic, J.; Anicin, I. [Faculty of Physics, University of Belgrade, Belgrade (Serbia and Montenegro)

    2007-04-23T23:59:59.000Z

    Two identical plastic scintillator detectors, of prismatic shape (50x23x5)cm similar to NE102, were used for continuous monitoring of cosmic-ray intensity. Muon {delta}E spectra have been taken at five minute intervals, simultaneously from the detector situated on the ground level and from the second one at the depth of 25 m.w.e in the low-level underground laboratory. Sum of all the spectra for the years 2002-2004 has been used to determine the cosmic-ray muon flux at the ground level and in the underground laboratory.

  15. Contactless heat flux control with photonic devices

    E-Print Network [OSTI]

    Ben-Abdallah, Philippe

    2015-01-01T23:59:59.000Z

    The ability to control electric currents in solids using diodes and transistors is undoubtedly at the origin of the main developments in modern electronics which have revolutionized the daily life in the second half of 20th century. Surprisingly, until the year 2000 no thermal counterpart for such a control had been proposed. Since then, based on pioneering works on the control of phononic heat currents new devices were proposed which allow for the control of heat fluxes carried by photons rather than phonons or electrons. The goal of the present paper is to summarize the main advances achieved recently in the field of thermal energy control with photons.

  16. Flux Power Incorporated | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489Information Hydro IncEnergyInformationOpenOpenFlux Power

  17. ARM - Field Campaign - ISDAC - Hemispheric Flux Spectroradiometer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8LigovCampaignsCLEX-5govCampaignsFall- Hemispheric Flux

  18. ATA injector-gun calculations

    SciTech Connect (OSTI)

    Paul, A.C.

    1981-08-03T23:59:59.000Z

    ATA is a pulsed, 50 ns 10 KA, 50 MeV linear induction electron accelerator at LLNL. The ETA could be used as an injector for ATA. However the possibility of building a new injector gun for ATA, raised the question as to what changes from the ETA gun in electrode dimensions or potentials, if any, should be considered. In this report the EBQ code results for the four electrode configurations are reviewed and an attempt is made to determine the geometrical scaling laws appropriate to these ETA type gun geometries. Comparison of these scaling laws will be made to ETA operation. The characteristic operating curves for these geometries will also be presented and the effect of washer position determined. It will be shown that emittance growth will impose a limitation on beam current for a given anode potential before the virtual cathode limit is reached.

  19. Shimmed electron beam welding process

    DOE Patents [OSTI]

    Feng, Ganjiang (Clifton Park, NY); Nowak, Daniel Anthony (Alplaus, NY); Murphy, John Thomas (Niskayuna, NY)

    2002-01-01T23:59:59.000Z

    A modified electron beam welding process effects welding of joints between superalloy materials by inserting a weldable shim in the joint and heating the superalloy materials with an electron beam. The process insures a full penetration of joints with a consistent percentage of filler material and thereby improves fatigue life of the joint by three to four times as compared with the prior art. The process also allows variable shim thickness and joint fit-up gaps to provide increased flexibility for manufacturing when joining complex airfoil structures and the like.

  20. Finding beam focus errors automatically

    SciTech Connect (OSTI)

    Lee, M.J.; Clearwater, S.H.; Kleban, S.D.

    1987-01-01T23:59:59.000Z

    An automated method for finding beam focus errors using an optimization program called COMFORT-PLUS. The steps involved in finding the correction factors using COMFORT-PLUS has been used to find the beam focus errors for two damping rings at the SLAC Linear Collider. The program is to be used as an off-line program to analyze actual measured data for any SLC system. A limitation on the application of this procedure is found to be that it depends on the magnitude of the machine errors. Another is that the program is not totally automated since the user must decide a priori where to look for errors. (LEW)

  1. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  2. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Department of Physics, Northern Illinois University, Dekalb, Illinois 60115 (United States); Accelerator Physics Center (APC), Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510 (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 10{sup 25?}m{sup ?3} and 1.6?×?10{sup 28?}m{sup ?3} plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers ?20% higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?{sub p} to 0.6 ?{sub p} in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g., nanotubes) of high electron plasma density.

  3. Calculation of wakefields in a 17 GHz beam-driven photonic band-gap accelerator structure

    E-Print Network [OSTI]

    Hu, Min

    We present the theoretical analysis and computer simulation of the wakefields in a 17 GHz photonic band-gap (PBG) structure for accelerator applications. Using the commercial code CST Particle Studio, the fundamental ...

  4. Transverse beam shape measurements of intense proton beams using optical transition radiation

    SciTech Connect (OSTI)

    Scarpine, Victor E.; /Fermilab

    2012-03-01T23:59:59.000Z

    A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.

  5. Thermographic calorimetry of the neutral beam injectors heating beams at TJ-II

    SciTech Connect (OSTI)

    Fuentes, C.; Liniers, M.; Guasp, J.; Doncel, J.; Botija, J.; Wolfers, G.; Alonso, J.; Acedo, M.; Sanchez, E.; Marcon, G.; Weber, M.; Carrasco, R.; Sarasola, X.; Zurro, B.; Tera, J. [Laboratorio Nacional de Fusion/Asociacion EURATOM-CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain)

    2006-10-15T23:59:59.000Z

    A new beam diagnostic based on infrared thermography has been developed for the neutral beam injectors of the stellarator TJ-II. A highly anisotropic movable target intercepts the beam at its entrance into the stellarator. The thermal print of the beam is captured with a high resolution infrared camera. The infrared images of the target can be translated, with the appropriate analysis, into power density patterns of the beam. The system is calibrated in situ with two thermocouples adiabatically mounted in the target. The two-dimensional beam power density distribution can be accurately characterized allowing beam optimization with respect to the different parameters involved in the beam formation and transport.

  6. Polarimetric Properties of Flux-Ropes and Sheared Arcades in Coronal Prominence Cavities

    E-Print Network [OSTI]

    Rachmeler, L A; Dove, J B; DeVore, C R; Fan, Y

    2013-01-01T23:59:59.000Z

    The coronal magnetic field is the primary driver of solar dynamic events. Linear and circular polarization signals of certain infrared coronal emission lines contain information about the magnetic field, and to access this information, either a forward or an inversion method must be used. We study three coronal magnetic configurations that are applicable to polar-crown filament cavities by doing forward calculations to produce synthetic polarization data. We analyze these forward data to determine the distinguishing characteristics of each model. We conclude that it is possible to distinguish between cylindrical flux ropes, spheromak flux ropes, and sheared arcades using coronal polarization measurements. If one of these models is found to be consistent with observational measurements, it will mean positive identification of the magnetic morphology that surrounds certain quiescent filaments, which will lead to a greater understanding of how they form and why they erupt.

  7. High energy laser beam dump

    DOE Patents [OSTI]

    Halpin, John (Tracy, CA)

    2004-09-14T23:59:59.000Z

    The laser beam dump is positioned in a housing. An absorbing glass plate means is operatively connected to the housing. A heat sync means for extracting heat from the absorbing glass plate means is operatively connected to the housing and operatively connected to the absorbing glass plate means.

  8. Relativistic atomic beam spectroscopy II

    SciTech Connect (OSTI)

    NONE

    1991-12-31T23:59:59.000Z

    We are requesting support for a postdoctoral person to participate in H{sup -} studies at Los Alamos. In addition, we are requesting funding for a state-of-the-art YAG laser system that would allow us to obtain data at three times our present rate with improved beam quality.

  9. Inverse Modeling of Hydrologic Parameters Using Surface Flux and Runoff Observations in the Community Land Model

    SciTech Connect (OSTI)

    Sun, Yu; Hou, Zhangshuan; Huang, Maoyi; Tian, Fuqiang; Leung, Lai-Yung R.

    2013-12-10T23:59:59.000Z

    This study demonstrates the possibility of inverting hydrologic parameters using surface flux and runoff observations in version 4 of the Community Land Model (CLM4). Previous studies showed that surface flux and runoff calculations are sensitive to major hydrologic parameters in CLM4 over different watersheds, and illustrated the necessity and possibility of parameter calibration. Two inversion strategies, the deterministic least-square fitting and stochastic Markov-Chain Monte-Carlo (MCMC) - Bayesian inversion approaches, are evaluated by applying them to CLM4 at selected sites. The unknowns to be estimated include surface and subsurface runoff generation parameters and vadose zone soil water parameters. We find that using model parameters calibrated by the least-square fitting provides little improvements in the model simulations but the sampling-based stochastic inversion approaches are consistent - as more information comes in, the predictive intervals of the calibrated parameters become narrower and the misfits between the calculated and observed responses decrease. In general, parameters that are identified to be significant through sensitivity analyses and statistical tests are better calibrated than those with weak or nonlinear impacts on flux or runoff observations. Temporal resolution of observations has larger impacts on the results of inverse modeling using heat flux data than runoff data. Soil and vegetation cover have important impacts on parameter sensitivities, leading to the different patterns of posterior distributions of parameters at different sites. Overall, the MCMC-Bayesian inversion approach effectively and reliably improves the simulation of CLM under different climates and environmental conditions. Bayesian model averaging of the posterior estimates with different reference acceptance probabilities can smooth the posterior distribution and provide more reliable parameter estimates, but at the expense of wider uncertainty bounds.

  10. Bunch length effects in the beam-beam compensation with an electron lens

    SciTech Connect (OSTI)

    Fischer, W.; Luo, Y.; Montag, C.

    2010-02-25T23:59:59.000Z

    Electron lenses for the head-on beam-beam compensation are under construction at the Relativistic Heavy Ion Collider. The bunch length is of the same order as the {beta}-function at the interaction point, and a proton passing through another proton bunch experiences a substantial phase shift which modifies the beam-beam interaction. We review the effect of the bunch length in the single pass beam-beam interaction, apply the same analysis to a proton passing through a long electron lens, and study the single pass beam-beam compensation with long bunches. We also discuss the beam-beam compensation of the electron beam in an electron-ion collider ring.

  11. antinucleon beams: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interaction of fields induced by the beam with their environment. Beam current transformers as well as beam position monitors are based on this principle. The signals induced...

  12. automatic beam alignment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interaction of fields induced by the beam with their environment. Beam current transformers as well as beam position monitors are based on this principle. The signals induced...

  13. accidental beam loss: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interaction of fields induced by the beam with their environment. Beam current transformers as well as beam position monitors are based on this principle. The signals induced...

  14. antiparticle beams: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interaction of fields induced by the beam with their environment. Beam current transformers as well as beam position monitors are based on this principle. The signals induced...

  15. accelerating beam stability: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    particle beams (beam intercepting devices BIDs). For the design of BIDs, the increasing heat load onto these devices due to energetic and focused beams and - in most cases -...

  16. accelerated oxygen-14 beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    particle beams (beam intercepting devices BIDs). For the design of BIDs, the increasing heat load onto these devices due to energetic and focused beams and - in most cases -...

  17. accelerator school beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    particle beams (beam intercepting devices BIDs). For the design of BIDs, the increasing heat load onto these devices due to energetic and focused beams and - in most cases -...

  18. Comparative study of 2-group P1 and diffusion theories for the calculation of the neutron noise in 1D 2-region systems

    E-Print Network [OSTI]

    Demazière, Christophe

    Comparative study of 2-group P1 and diffusion theories for the calculation of the neutron noise of the neutron flux around its mean value, is calculated in 2-group P1 and diffusion theories for a 2-region slab reactor using Green's function technique. The applicability of diffusion theory for different types

  19. R E S E A R C H A R T I C L E Calculation of total free energy yield as an alternative

    E-Print Network [OSTI]

    Ahmad, Sajjad

    R E S E A R C H A R T I C L E Calculation of total free energy yield as an alternative approach Sobecky Keywords thermodynamics; chemolithotrophy; energy flux; free energy yield; ammonia oxidation in geothermal environments, we calculated free energy yields of 26 chemical reactions potentially supporting

  20. R E S E A R C H A R T I C L E Calculation of total free energy yield as an alternative

    E-Print Network [OSTI]

    Ahmad, Sajjad

    R E S E A R C H A R T I C L E Calculation of total free energy yield as an alternative approach flux; free energy yield; ammonia oxidation. Abstract To inform hypotheses regarding the relative importance of chemolithotrophic metabolisms in geothermal environments, we calculated free energy yields

  1. AmeriFlux Measurement Network: Science Team Research

    SciTech Connect (OSTI)

    Law, B E

    2012-12-12T23:59:59.000Z

    Research involves analysis and field direction of AmeriFlux operations, and the PI provides scientific leadership of the AmeriFlux network. Activities include the coordination and quality assurance of measurements across AmeriFlux network sites, synthesis of results across the network, organizing and supporting the annual Science Team Meeting, and communicating AmeriFlux results to the scientific community and other users. Objectives of measurement research include (i) coordination of flux and biometric measurement protocols (ii) timely data delivery to the Carbon Dioxide Information and Analysis Center (CDIAC); and (iii) assurance of data quality of flux and ecosystem measurements contributed by AmeriFlux sites. Objectives of integration and synthesis activities include (i) integration of site data into network-wide synthesis products; and (ii) participation in the analysis, modeling and interpretation of network data products. Communications objectives include (i) organizing an annual meeting of AmeriFlux investigators for reporting annual flux measurements and exchanging scientific information on ecosystem carbon budgets; (ii) developing focused topics for analysis and publication; and (iii) developing data reporting protocols in support of AmeriFlux network goals.

  2. FLUX MEASUREMENTS FROM A TALL TOWER IN A COMPLEX LANDSCAPE

    SciTech Connect (OSTI)

    Kurzeja, R.; Weber, A.; Chiswell, S.; Parker, M.

    2010-07-22T23:59:59.000Z

    The accuracy and representativeness of flux measurements from a tall tower in a complex landscape was assessed by examining the vertical and sector variability of the ratio of wind speed to momentum flux and the ratio of vertical advective to eddy flux of heat. The 30-60 m ratios were consistent with theoretical predictions which indicate well mixed flux footprints. Some variation with sector was observed that were consistent with upstream roughness. Vertical advection was negligible compared with vertical flux except for a few sectors at night. This implies minor influence from internal boundary layers. Flux accuracy is a function of sector and stability but 30-60 m fluxes were found to be generally representative of the surrounding landscape. This paper will study flux data from a 300 m tower, with 4 levels of instruments, in a complex landscape. The surrounding landscape will be characterized in terms of the variation in the ratio of mean wind speed to momentum flux as a function of height and wind direction. The importance of local advection will be assessed by comparing vertical advection with eddy fluxes for momentum and heat.

  3. Analysis of Shot Noise Suppression for Electron Beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ratner, Daniel; Huang, Zhirong; Stupakov, Gennady

    2015-02-02T23:59:59.000Z

    Shot noise can affect the performance of free-electron lasers (FELs) by driving instabilities (e.g., the microbunching instability) or by competing with seeded density modulations. Recent papers have proposed suppressing shot noise to enhance FEL performance. In this paper we use a onedimensional (1D) model to calculate the noise amplification from an energy modulation (e.g., electron interactions from space charge or undulator radiation) followed by a dispersive section. We show that, for a broad class of interactions, selecting the correct dispersive strength suppresses shot noise across a wide range of frequencies. The final noise level depends on the beam’s energy spread and the properties of the interaction potential. We confirm and illustrate our analytical results with 1D simulations.

  4. Upgrade of the lithium beam diagnostic at JET

    SciTech Connect (OSTI)

    Brix, M.; Korotkov, A.; Morgan, P.; Meigs, A.; Vince, J. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Dodt, D.; Fischer, R.; Schweinzer, J. [Max Planck Institut fuer Plasmaphysik, EURATOM-Association IPP, D-85748 Garching (Germany); Dunai, D.; Zoletnik, S. [KFKI RMKI, EURATOM Association, P.O. Box 49, H-1525 Budapest (Hungary); Nedzelskiy, I. S. [Association EURATOM/IST, Instituto de Plasma e FuSao Nuclear, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal); Collaboration: JET-EFDA Contributors

    2010-10-15T23:59:59.000Z

    A 60 kV neutral Li beam is injected into the edge plasma of JET to measure the electron density. The beam observation system has been improved by replacing a Czerny-Turner spectrometer with a high-resolution transmission-grating spectrometer and a fast back-illuminated frame-transfer camera. The larger throughput of the spectrometer, the increased sensitivity, and the faster readout of the new camera allow inter-ELM (edge localized mode) measurements (frame rate of 100 Hz). The calibration of the setup, as well as an improved spectral fitting technique in the presence of carbon background radiation, is discussed in detail. The density calculation is based on a statistical analysis method. Results are presented for different plasma scenarios.

  5. Monte Carlo uncertainty reliability and isotope production calculations for a fast reactor

    SciTech Connect (OSTI)

    Miles, T.L.

    1992-01-01T23:59:59.000Z

    Statistical uncertainties in Monte Carlo calculations are typically determined by the first and second moments of the tally. For certain types of calculations, there is concern that the uncertainty estimate is significantly non-conservative. This is typically seen in reactor eigenvalue problems where the uncertainty estimate is aggravated by the generation-to-generation fission source. It has been speculated that optimization of the random walk, through biasing techniques, may increase the non-conservative nature of the uncertainty estimate. A series of calculations are documented here which quantify the reliability of the Monte Carlo Neutron and Photon (MCNP) mean and uncertainty estimates by comparing these estimates to the true mean. These calculations were made with a liquid metal fast reactor model, but every effort was made to isolate the statistical nature of the uncertainty estimates so that the analysis of the reliability of the MCNP estimates should be relevant for small thermal reactors as well. Also, preliminary reactor physics calculations for two different special isotope production test assemblies for irradiation in the Fast Flux Test Facility (FFTF) were performed using MCNP and are documented here. The effect of an yttrium-hydride moderator to tailor the neutron flux incident on the targets to maximize isotope production for different designs in different locations within the reactor is discussed. These calculations also demonstrate the useful application of MCNP in design iterations by utilizing many of the codes features.

  6. Low-Enriched Uranium Fuel Design with Two-Dimensional Grading for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Ilas, Germina [ORNL; Primm, Trent [ORNL

    2011-05-01T23:59:59.000Z

    An engineering design study of the conversion of the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel is ongoing at Oak Ridge National Laboratory. The computational models developed during fiscal year 2010 to search for an LEU fuel design that would meet the requirements for the conversion and the results obtained with these models are documented and discussed in this report. Estimates of relevant reactor performance parameters for the LEU fuel core are presented and compared with the corresponding data for the currently operating HEU fuel core. The results obtained indicate that the LEU fuel design would maintain the current performance of the HFIR with respect to the neutron flux to the central target region, reflector, and beam tube locations under the assumption that the operating power for the reactor fueled with LEU can be increased from the current value of 85 MW to 100 MW.

  7. SU?C?105?05: Reference Dosimetry of High?Energy Electron Beams with a Farmer?Type Ionization Chamber

    SciTech Connect (OSTI)

    Muir, B; Rogers, D [Carleton University, Ottawa, ON (Canada)] [Carleton University, Ottawa, ON (Canada)

    2013-06-15T23:59:59.000Z

    Purpose: To investigate gradient effects and provide Monte Carlo calculated beam quality conversion factors to characterize the Farmer?type NE2571 ion chamber for high?energy reference dosimetry of clinical electron beams. Methods: The EGSnrc code system is used to calculate the absorbed dose to water and to the gas in a fully modeled NE2571 chamber as a function of depth in a water phantom. Electron beams incident on the surface of the phantom are modeled using realistic BEAMnrc accelerator simulations and electron beam spectra. Beam quality conversion factors are determined using calculated doses to water and to air in the chamber in high?energy electron beams and in a cobalt?60 reference field. Calculated water?to?air stopping power ratios are employed for investigation of the overall ion chamber perturbation factor. Results: An upstream shift of 0.3–0.4 multiplied by the chamber radius, r-cav, both minimizes the variation of the overall ion chamber perturbation factor with depth and reduces the difference between the beam quality specifier (R{sub 5} {sub 0}) calculated using ion chamber simulations and that obtained with simulations of dose?to?water in the phantom. Beam quality conversion factors are obtained at the reference depth and gradient effects are optimized using a shift of 0.2r-cav. The photon?electron conversion factor, k-ecal, amounts to 0.906 when gradient effects are minimized using the shift established here and 0.903 if no shift of the data is used. Systematic uncertainties in beam quality conversion factors are investigated and amount to between 0.4 to 1.1% depending on assumptions used. Conclusion: The calculations obtained in this work characterize the use of an NE2571 ion chamber for reference dosimetry of high?energy electron beams. These results will be useful as the AAPM continues to review their reference dosimetry protocols.

  8. Transport of elliptic intense charged -particle beams

    E-Print Network [OSTI]

    Zhou, J. (Jing), 1978-

    2006-01-01T23:59:59.000Z

    The transport theory of high-intensity elliptic charged-particle beams is presented. In particular, the halo formation and beam loss problem associated with the high space charge and small-aperture structure is addressed, ...

  9. Neutral particle beam sensing and steering

    DOE Patents [OSTI]

    Maier, II, William B. (Los Alamos, NM); Cobb, Donald D. (Los Alamos, NM); Robiscoe, Richard T. (Los Alamos, NM)

    1991-01-01T23:59:59.000Z

    The direction of a neutral particle beam (NPB) is determined by detecting Ly.alpha. radiation emitted during motional quenching of excited H(2S) atoms in the beam during movement of the atoms through a magnetic field. At least one detector is placed adjacent the beam exit to define an optical axis that intercepts the beam at a viewing angle to include a volume generating a selected number of photons for detection. The detection system includes a lens having an area that is small relative to the NPB area and a pixel array located in the focal plane of the lens. The lens viewing angle and area pixel array are selected to optimize the beam tilt sensitivity. In one embodiment, two detectors are placed coplanar with the beam axis to generate a difference signal that is insensitive to beam variations other than beam tilt.

  10. On Gaussian Beams Described by Jacobi's Equation

    E-Print Network [OSTI]

    Smith, Steven T.

    Gaussian beams describe the amplitude and phase of rays and are widely used to model acoustic propagation. This paper describes four new results in the theory of Gaussian beams. (1) A new version of the ?ervený equations ...

  11. Autogenerator of beams of charged particles

    DOE Patents [OSTI]

    Adler, R.J.; Mazarakis, M.G.; Miller, R.M.; Shope, S.L.; Smith, D.L.

    1983-10-31T23:59:59.000Z

    An autogenerating apparatus provides secondary intense relativistic current beam pulses in response to an injected beam pulse. One or more electromagnetic energy storage devices are provided in conjunction with gaps along a beam propagation path for the injected beam pulse. For injected beam pulses which are no longer than double the transit time of electromagnetic waves within the storage devices (which may be resonant cavities), distinct secondary beam pulses are generated by each of the energy storage devices. The beam propagation path, together with the one or more gaps provided therein, operates as a pulse forming transmission line cavity, in which the separate cavities associated with the gaps provide delays for electromagnetic waves generated at the gaps. After doubly traversing the cavity, the electromagnetic waves cause the gap to generate the secondary beam pulses, which are thus delayed by a time interval equal to the double transit time for the induced wave within the cavity.

  12. Autogenerator of beams of charged particles

    DOE Patents [OSTI]

    Adler, Richard J. (Albuquerque, NM); Mazarakis, Michael G. (Albuquerque, NM); Miller, Robert B. (Albuquerque, NM); Shope, Steven L. (Albuquerque, NM); Smith, David L. (Albuquerque, NM)

    1986-01-01T23:59:59.000Z

    An autogenerating apparatus provides secondary intense relativistic current beam pulses in response to an injected beam pulse. One or more electromagnetic energy storage devices are provided in conjunction with gaps along a beam propagation path for the injected beam pulse. For injected beam pulses which are no longer than double the transit time of electromagnetic waves within the storage devices (which may be resonant cavities), distinct secondary beam pulses are generated by each of the energy storage devices. The beam propagation path, together with the one or more gaps provided therein, operates as a pulse forming transmission line cavity, in which the separate cavities associated with the gaps provide delays for electromagnetic waves generated at the gaps. After doubly traversing the cavity, the electromagnetic waves cause the gap to generate the secondary beam pulses, which are thus delayed by a time interval equal to the double transit time for the induced wave within the cavity.

  13. Harmonic Analysis Errors in Calculating Dipole,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to reduce the harmonic field calculation errors. A conformal transfor- mation of a multipole magnet into a dipole reduces these errors. Dipole Magnet Calculations A triangular...

  14. Cost Recovery Charge (CRC) Calculation Tables

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cost Recovery Charge (CRC) Calculation Table Updated: March 20, 2015 FY 2016 February 2015 CRC Calculation Table (pdf) Final FY 2015 CRC Letter & Table (pdf) Note: The Cost...

  15. NERSC Calculations Provide Independent Confirmation of Global...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Calculations Provide Independent Confirmation of Global Land Warming Since 1901 NERSC Calculations Provide Independent Confirmation of Global Land Warming Since 1901 September 9,...

  16. Calculation of shielding door thicknesses for radiation therapy facilities using the ITS Monte Carlo program

    SciTech Connect (OSTI)

    Biggs, P.J. (Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston (United States))

    1991-10-01T23:59:59.000Z

    Shielding calculations for door thicknesses for megavoltage radiotherapy facilities with mazes are generally straightforward. To simplify the calculations, the standard formalism adopts several approximations relating to the average beam path, scattering coefficients, and the mean energy of the spectrum of scattered radiation. To test the accuracy of these calculations, the Monte Carlo program, ITS, was applied to this problem by determining the dose and energy spectrum of the radiation at the door for 4- and 10-MV bremsstrahlung beams incident on a phantom at isocenter. This was performed for mazes, one termed 'standard' and the other a shorter maze where the primary beam is incident on the wall adjacent to the door. The peak of the photon-energy spectrum at the door was found to be the same for both types of maze, independent of primary beam energy, and also, in the case of the conventional maze, of the primary beam orientation. The spectrum was harder for the short maze and for 10 MV vs. 4 MV. The thickness of the lead door for a short maze configuration was 1.5 cm for 10 MV and 1.2 cm for 4 MV vs. approximately less than 1 mm for a conventional maze. For the conventional maze, the Monte Carlo calculation predicts the dose at the door to be lower than given by NCRP 49 and NCRP 51 by about a factor of 2 at 4 MV but to be the same at 10 MV. For the short maze, the Monte Carlo predicts the dose to be a factor of 3 lower for 4 MV and about a factor of 1.5 lower for 10 MV. Experimental results support the Monte Carlo findings for the short maze.

  17. Maskless, resistless ion beam lithography

    SciTech Connect (OSTI)

    Ji, Qing

    2003-03-10T23:59:59.000Z

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O{sub 2}{sup +}, BF{sub 2}{sup +}, P{sup +} etc., for surface modification and doping applications. With optimized source condition, around 85% of BF{sub 2}{sup +}, over 90% of O{sub 2}{sup +} and P{sup +} have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He{sup +} beam is as high as 440 A/cm{sup 2} {center_dot} Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O{sub 2}{sup +} ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O{sub 2}{sup +} ions with the dose of 10{sup 15} cm{sup -2}. The oxide can then serve as a hard mask for patterning of the Si film. The process flow and the experimental results for directly patterned poly-Si features are presented. The formation of shallow pn-junctions in bulk silicon wafers by scanning focused P{sup +} beam implantation at 5 keV is also presented. With implantation dose of around 10{sup 16} cm{sup -2}, the electron concentration is about 2.5 x 10{sup 18} cm{sup -3} and electron mobility is around 200 cm{sup 2}/V{center_dot}s. To demonstrate the suitability of scanning FIB lithography for the manufacture of integrated circuit devices, SOI MOSFET fabrication using the maskless, resistless ion beam lithography is demonstrated. An array of microcolumns can be built by stacking multi-aperture electrode and insulator layers. Because the multicusp plasma source can achieve uniform ion density over a large area, it can be used in conjunction with the array of microcolumns, for massively parallel FIB processing to achieve reasonable exposure throughput.

  18. Turbulent Fluxes in Stably Stratified Boundary Layers

    E-Print Network [OSTI]

    L'vov, Victor S; Rudenko, Oleksii; 10.1088/0031-8949/2008/T132/014010

    2008-01-01T23:59:59.000Z

    We present an extended version of an invited talk given on the International Conference "Turbulent Mixing and Beyond". The dynamical and statistical description of stably stratified turbulent boundary layers with the important example of the stable atmospheric boundary layer in mind is addressed. Traditional approaches to this problem, based on the profiles of mean quantities, velocity second-order correlations, and dimensional estimates of the turbulent thermal flux run into a well known difficulty, predicting the suppression of turbulence at a small critical value of the Richardson number, in contradiction with observations. Phenomenological attempts to overcome this problem suffer from various theoretical inconsistencies. Here we present an approach taking into full account all the second-order statistics, which allows us to respect the conservation of total mechanical energy. The analysis culminates in an analytic solution of the profiles of all mean quantities and all second-order correlations removing t...

  19. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, F.; Cohen, S.A.; Bennett, T.; Timberlake, J.R.

    1993-08-24T23:59:59.000Z

    An apparatus is described for measuring momentum flux from an intense plasma stream, comprising: refractory target means oriented normal to the flow of said plasma stream for bombardment by said plasma stream where said bombardment by said plasma stream applies a pressure to said target means, pendulum means for communicating a translational displacement of said target to a force transducer where said translational displacement of said target is transferred to said force transducer by an elongated member coupled to said target, where said member is suspended by a pendulum configuration means and where said force transducer is responsive to said translational displacement of said member, and force transducer means for outputting a signal representing pressure data corresponding to said displacement.

  20. Permanent-magnet switched-flux machine

    DOE Patents [OSTI]

    Trzynadlowski, Andrzej M.; Qin, Ling

    2010-01-12T23:59:59.000Z

    A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

  1. Tracking heat flux sensors for concentrating solar applications

    DOE Patents [OSTI]

    Andraka, Charles E; Diver, Jr., Richard B

    2013-06-11T23:59:59.000Z

    Innovative tracking heat flux sensors located at or near the solar collector's focus for centering the concentrated image on a receiver assembly. With flux sensors mounted near a receiver's aperture, the flux gradient near the focus of a dish or trough collector can be used to precisely position the focused solar flux on the receiver. The heat flux sensors comprise two closely-coupled thermocouple junctions with opposing electrical polarity that are separated by a thermal resistor. This arrangement creates an electrical signal proportional to heat flux intensity, and largely independent of temperature. The sensors are thermally grounded to allow a temperature difference to develop across the thermal resistor, and are cooled by a heat sink to maintain an acceptable operating temperature.

  2. Laser Telecommunication timeLaser beam

    E-Print Network [OSTI]

    La Rosa, Andres H.

    Laser Telecommunication Experiment Laser time Laser beam intensity timeLaser beam Laser battery Laser connected to a circuit without a modulator. Bottom graph illustrates what happen when a modulating signal is superimposed to the DC voltage driving the laser Laser beam intensity DC Input voltage DC

  3. Nondestructive Damage Detection in General Beams 

    E-Print Network [OSTI]

    Dincal, Selcuk

    2010-12-08T23:59:59.000Z

    Representation of the First Damage Case on the Finite Element Mesh of the Slender Beam ...................................................... 41 Figure 3.12 Schematic Representation of the Second Damage Case on the Finite Element Mesh... of the Slender Beam ...................................................... 42 Figure 3.13 Schematic Representation of the Third Damage Case on the Finite Element Mesh of the Slender Beam ...................................................... 44...

  4. JET neutral beam power upgrade Introduction

    E-Print Network [OSTI]

    JET neutral beam power upgrade Introduction A tokamak is a complex assembly, a system of systems the challenging requirements that fusion demands. The neutral beam heating system and its upgrade for the JET systems) are the main plasma heating scheme on fusion devices such as JET and ITER. The JET neutral beam

  5. Beam heat load in superconducting wigglers

    E-Print Network [OSTI]

    Casalbuoni, S

    2013-01-01T23:59:59.000Z

    The beam heat load is a fundamental input parameter for the design of superconducting wigglers since it is needed to specify the cooling power. In this presentation I will review the possible beam heat load sources and the measurements of beam heat load performed and planned onto the cold vacuum chambers installed at different synchrotron light sources.

  6. Lateral stability of long precast concrete beams

    E-Print Network [OSTI]

    Burgoyne, Chris

    buckling L length of beam vx lateral de¯ection measured in the minor- axis direction (which rotates with yLateral stability of long precast concrete beams T. J. Stratford, BA, BEng, and C. J. Burgoyne, BA, making them more susceptible to buckling failure. This paper shows that once the beam is positioned

  7. Bounding Radionuclide Inventory and Accident Consequence Calculation for the 1L Target

    SciTech Connect (OSTI)

    Kelsey, Charles T. IV [Los Alamos National Laboratory

    2011-01-01T23:59:59.000Z

    A bounding radionuclide inventory for the tungsten of the Los Alamos Neutron Science Center (LANSCE) IL Target is calculated. Based on the bounding inventory, the dose resulting from the maximum credible incident (MCI) is calculated for the maximally exposed offsite individual (MEOl). The design basis accident involves tungsten target oxidation following a loss of cooling accident. Also calculated for the bounding radionuclide inventory is the ratio to the LANSCE inventory threshold for purposes of inventory control as described in the target inventory control policy. A bounding radionuclide inventory calculation for the lL Target was completed using the MCNPX and CINDER'90 codes. Continuous beam delivery at 200 {micro}A to 2500 mA{center_dot}h was assumed. The total calculated activity following this irradiation period is 205,000 Ci. The dose to the MEOI from the MCI is 213 mrem for the bounding inventory. The LANSCE inventory control threshold ratio is 132.

  8. Techniques for evaluation of e-beam evaporative processes

    SciTech Connect (OSTI)

    Meier, T.C.; Nelson, C.M. [Lawrence Livermore National Lab., CA (United States)

    1996-12-31T23:59:59.000Z

    Efforts to evaluate and characterize electron beam evaporative processes at LLNL have produced a number of techniques and capabilities which have proven useful in advancing the process understanding. One of these diagnostic tools, high dynamic range video imaging of the molten pool surface, has provided insight regarding process responses at the melt pool liquid-vapor interface. A water cooled video camera provides continuous high resolution imaging of the pool surface from a low angle position within 20 cm of the liquid-vapor interface. From this vantage point, the e-beam footprint is clearly defined and melt pool free surface shape can be observed. Effects of changes in e-beam footprint, power distribution and sweep frequency on pool surface shape and stability of vaporization are immediately shown. Other electron beam melting and vaporization events have been observed and recorded. These include: formation of the pool and dissipation of {open_quotes}rafts{close_quotes} on the pool surface during startup, behavior of feed material as it enters the pool, effects of feed configuration changes on the mixing of feed entering the pool volume and behaviors of co-evaporated materials of different vapor pressures at the feed/pool boundary. When used in conjunction with laser vapor monitoring capabilities (presented at the 1994 Electron Beam Melting and Refining Conference, Reno, NV), correlation between pool surface phenomena and vaporizer performance has been identified. This video capability was used in verifying the titanium evaporation model results presented at this conference by confirming the calculated melt pool surface deformations caused by vapor pressure of the departing evaporant at the liquid-vapor interface.

  9. Results of long range beam-beam studies and observations during operation in the LHC

    E-Print Network [OSTI]

    Alemany, R; Buffat, X; Calaga, R; Fitterer, M; Giachino, R; Hemelsoet, GH; Herr, W; Papotti, G; Pieloni, T; Poyer, M; Schaumann, M; Trad, G; Wollmann, D

    2011-01-01T23:59:59.000Z

    We studied possible limitations due to the long range beam-beam effects in the LHC. With a larger number of bunches and collisions in all interaction points, we have reduced the crossing angles to enhance long range beam-beam effects to evaluate their influence on dynamic aperture and losses. Experience from operation with reduced separation was analysed and provides additional evidence.

  10. Exact-to-precision generalized perturbation for neutron transport calculation

    SciTech Connect (OSTI)

    Wang, C.; Abdel-Khalik, H. S. [North Carolina State University, 911 Oval Dr., Centennial Campus, Raleigh, NC 27606 (United States)

    2013-07-01T23:59:59.000Z

    This manuscript extends the exact-to-precision generalized perturbation theory (E{sub P}GPT), introduced previously, to neutron transport calculation whereby previous developments focused on neutron diffusion calculation only. The E{sub P}GPT collectively denotes new developments in generalized perturbation theory (GPT) that place premium on computational efficiency and defendable accuracy in order to render GPT a standard analysis tool in routine design and safety reactor calculations. EPGPT constructs a surrogate model with quantifiable accuracy which can replace the original neutron transport model for subsequent engineering analysis, e.g. functionalization of the homogenized few-group cross sections in terms of various core conditions, sensitivity analysis and uncertainty quantification. This is achieved by reducing the effective dimensionality of the state variable (i.e. neutron angular flux) by projection onto an active subspace. Confining the state variations to the active subspace allows one to construct a small number of what is referred to as the 'active' responses which are solely dependent on the physics model rather than on the responses of interest, the number of input parameters, or the number of points in the state phase space. (authors)

  11. Physical Programm and Acceleration of Polarized Light Nuclei Beams at Jinr Nuclotron

    E-Print Network [OSTI]

    S. Vokal; A. D. Kovalenko; A. M. Kondratenko; M. A. Kondratenko; V. A. Mikhailov; Yu. N. Filatov; S. S. Shimanskiy

    2008-02-28T23:59:59.000Z

    The physical spin program at high $p_T$ region and energies $s^{1/2}_{NN} \\sim 10 GeV$ is discussed. It's shown that cumulative processes, color transparency problem and polarization phenomenons directly connect with properties new form of the nuclear matter as Color Quark Condensate(CQC). Studies of CQC one of the most important physical problem and can be realized using polarized ion beams at JINR nuclotron-M (and in future at NICA). The calculations of spin resonance strengthes in the linear approximation for p, d, t and $^3He$ beams in the JINR nuclotron are presented. The methods to preserve the degree of polarization during crossing the spin resonances are examined. The method of matching the direction of polarization vector during the beam injection in to the ring of the nuclotron is given. These methods of spin resonance crossing can be used to accelerate polarized beams in the other cyclic accelerators.

  12. Numerical simulation of material and energy flow in an e-beam melt furnace

    SciTech Connect (OSTI)

    Westerberg, K.W.; McClelland, M.A. [Lawrence Livermore National Lab., CA (United States); Finlayson, B.A. [Washington Univ., Seattle, WA (United States). Dept. of Chemical Engineering

    1993-12-01T23:59:59.000Z

    A numerical analysis is made of the material and energy flow in an electron-beam furnace. Energy from an electron beam vaporizes metal confined in a water-cooled crucible. At the beam impact site a. recirculating liquid metal pool is surrounded by a shell of its own solid. A Galerkin finite element method is modified to solve for the flow and temperature fields along with interface locations. The deforming mesh is parameterized using spines that pivot and stretch as the interfaces move. Results are given for an aluminum vaporizer in which parametric variations are made in the e-beam power and liquid viscosity. The calculations reveal the importance of the coupling between the free boundaries and the flow and energy fields.

  13. A simple algorithm for beam profile diagnostics using a thermographic camera

    SciTech Connect (OSTI)

    Katagiri, Ken; Hojo, Satoru; Honma, Toshihiro; Suzuki, Kazutoshi; Noda, Akira; Noda, Koji [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)] [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2014-03-15T23:59:59.000Z

    A new algorithm for digital image processing apparatuses is developed to evaluate profiles of high-intensity DC beams from temperature images of irradiated thin foils. Numerical analyses are performed to examine the reliability of the algorithm. To simulate the temperature images acquired by a thermographic camera, temperature distributions are numerically calculated for 20 MeV proton beams with different parameters. Noise in the temperature images which is added by the camera sensor is also simulated to account for its effect. Using the algorithm, beam profiles are evaluated from the simulated temperature images and compared with exact solutions. We find that niobium is an appropriate material for the thin foil used in the diagnostic system. We also confirm that the algorithm is adaptable over a wide beam current range of 0.11–214 ?A, even when employing a general-purpose thermographic camera with rather high noise (?T{sub NETD} ? 0.3 K; NETD: noise equivalent temperature difference)

  14. Flux avalanches in superconducting films with periodic arrays of holes.

    SciTech Connect (OSTI)

    Vlasko-Vlasov, V.; Welp, U.; Metlushko, V.; Crabtree, G. W.; Materials Science Division; Inst. of Solid State Physics RAS

    2000-01-01T23:59:59.000Z

    The magnetic flux dynamics in Nb films with periodic hole arrays is studied magneto-optically. Flux motion in the shape of microavalanches along {l_brace}100{r_brace} and {l_brace}110{r_brace} directions of the hole lattice is observed. At lower temperatures anisotropic large scale thermo-magnetic avalanches dominate flux entry and exit. At T-T{sub c} critical-state-like field patterns periodically appear at fractions of the matching field.

  15. Shifting the Position of Focal Point of Proton Beam Relative to Intersection Point with

    E-Print Network [OSTI]

    McDonald, Kirk

    .5 cm, then we can estimate the Twiss parameters at z = 37.5 from = L/*, = *+ L2/*, = *sqrt(1+L2, with the estimated Twiss parameters at z = 37.5 cm without the HG target in the IDS120h configuration, back to find the beam distribution at different planes in z, and calculate the corresponding Twiss parameters in each

  16. The Effect of Thermal Load Configurations on Passive Chilled Beam Performance

    E-Print Network [OSTI]

    Nelson, Ian 1982-

    2012-11-15T23:59:59.000Z

    dynamics (CFD) model was developed in Star CCM+ v6.06 and used for further analysis of the flow field and to predict additional spatial arrangements of the beam, interior dimensions, and heat source configurations. The CFD model implemented a calculation...

  17. Electron beam diagnostic for space charge measurement of an ion beam

    SciTech Connect (OSTI)

    Roy, Prabir K.; Yu, Simon S.; Henestroza, Enrique; Eylon, Shmuel; Shuman, Derek B.; Ludvig, Jozsef; Bieniosek, Frank M.; Waldron, William L.; Greenway, Wayne G.; Vanecek, David L.; Hannink, Ryan; Amezcua, Monserrat

    2004-09-25T23:59:59.000Z

    A non-perturbing electron beam diagnostic system for measuring the charge distribution of an ion beam is developed for Heavy Ion Fusion (HIF) beam physics studies. Conventional diagnostics require temporary insertion of sensors into the beam, but such diagnostics stop the beam, or significantly alter its properties. In this diagnostic a low energy, low current electron beam is swept transversely across the ion beam; the measured electron beam deflection is used to infer the charge density profile of the ion beam. The initial application of this diagnostic is to the Neutralized Transport Experiment (NTX), which is exploring the physics of space-charge-dominated beam focusing onto a small spot using a neutralizing plasma. Design and development of this diagnostic and performance with the NTX ion beamline is presented.

  18. Calculate viscosities for 355 liquids

    SciTech Connect (OSTI)

    Yaws, C.L.; Lin, Xiaoyan; Li Bu (Lamar Univ., TX (United States))

    1994-04-01T23:59:59.000Z

    Liquid viscosities are important factors in process design and operation. The viscosity of a liquid determines its flow properties, such as velocity and pressure drop. In addition, the heat- and mass-transfer characteristics of a liquid are affected by its viscosity. An equation can be used to calculate liquid viscosities as a function of temperature. In the accompanying table, regression coefficients are included for 355 compounds with five, six or seven carbon atoms--generally the most-widely used in the chemical and petroleum industries. To calculate the viscosity of a liquid at any temperature between its melting and critical points (T[sub min] and T[sub max]), use the following equation: log[sub 10] [eta][sub liq] = A + B/T + CT + DT[sup 2] where [eta][sub liq] = viscosity, cP, A,B,C and D = regression coefficients, and T = liquid temperature, K. Insert the temperature into the equation along with the corresponding regression coefficients from the table. The chemical formulae are listed by the number of carbon atoms.

  19. Nonlinear Plasma Waves Excitation by Intense Ion Beams in Background Plasma

    SciTech Connect (OSTI)

    Igor D. Kaganovich; Edward A. Startsev; Ronald C. Davidson

    2004-04-15T23:59:59.000Z

    Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration {tau}{sub b} is much longer than the electron plasma period 2{pi}/{omega}{sub p}, where {omega}{sub p} = (4{pi}e{sup 2}n{sub p}/m){sup 1/2} is the electron plasma frequency and n{sub p} is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma.

  20. Summary of session 3 on synchrotron radiation and beam dynamics

    SciTech Connect (OSTI)

    Shiltsev, V.; /Fermilab; Metral, E.; /CERN

    2010-12-01T23:59:59.000Z

    We summarize presentations, discussions and general conclusions of the Workshop session on 'Beam Dynamics Issues'. Major subjects include effects due to synchrotron radiation (SR), cryogenic loads, electron cloud, impedances, intra-beam scattering (IBS) and beam-beam interactions.