National Library of Energy BETA

Sample records for beam calculated flux

  1. SNS Sample Activation Calculator Flux Recommendations and Validation

    SciTech Connect (OSTI)

    McClanahan, Tucker C.; Gallmeier, Franz X.; Iverson, Erik B.; Lu, Wei

    2015-02-01

    The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) uses the Sample Activation Calculator (SAC) to calculate the activation of a sample after the sample has been exposed to the neutron beam in one of the SNS beamlines. The SAC webpage takes user inputs (choice of beamline, the mass, composition and area of the sample, irradiation time, decay time, etc.) and calculates the activation for the sample. In recent years, the SAC has been incorporated into the user proposal and sample handling process, and instrument teams and users have noticed discrepancies in the predicted activation of their samples. The Neutronics Analysis Team validated SAC by performing measurements on select beamlines and confirmed the discrepancies seen by the instrument teams and users. The conclusions were that the discrepancies were a result of a combination of faulty neutron flux spectra for the instruments, improper inputs supplied by SAC (1.12), and a mishandling of cross section data in the Sample Activation Program for Easy Use (SAPEU) (1.1.2). This report focuses on the conclusion that the SAPEU (1.1.2) beamline neutron flux spectra have errors and are a significant contributor to the activation discrepancies. The results of the analysis of the SAPEU (1.1.2) flux spectra for all beamlines will be discussed in detail. The recommendations for the implementation of improved neutron flux spectra in SAPEU (1.1.3) are also discussed.

  2. Updated flux information for neutron scattering and irradiation facilities at the BNL High Flux Beam Reactor

    SciTech Connect (OSTI)

    Holden, N.E.; Hu, J.P.; Reciniello, R.N.; Sengupta, S.; Greenwood, L.R.; Farrell, K.

    1997-08-01

    The HFBR is a heavy water, D{sub 2}O, cooled and moderated reactor with twenty-eight fuel elements containing a maximum of 9.8 kilograms of {sup 235}U. While most reactors attempt to minimize the escape of neutrons from the core, the HFBR`s D{sub 2}O design allows the thermal neutron flux to peak in the reflector region and maximizes the number of thermal neutrons available to nine horizontal external beams, H-1 to H-9, used for neutron scattering and capture reactions, supporting physics, chemistry and biology experiments. All horizontal beam tubes were built tangential to the direction of the emerging neutrons, except for the H-2 beam tube, which looks directly at the core and has been used for neutron cross section measurements utilizing fast neutrons and for the TRISTAN fission product studies. In recent years, there have been some beam modifications and new instrumentation introduced at the HFBR. A high resolution neutron powder diffractometer instrument is now operating with a resolution of 5 {times} 10{sup {minus}4} at horizontal beam line H-1. To study scattering from liquid surfaces, a neutron reflection spectrometer was introduced on the CNF beam line at H-9. In the past year, a fourth beam line has been added to the CNF line at H-9. The existing beam plug at the H-6 beam line has recently been removed and a new plug, which will feature super mirrored surfaces, is now being installed. Last year, the vertical beam thimble, V-13, a fixed port filled with thirty year old samples used for HFBR material surveillance studies was replaced by a new thimble and charging station at the core edge creating an irradiation facility to substitute for the original V-13. A neutron dosimetry program has begun to measure and calculate the energy dependent neutron and gamma ray flux densities and/or dose rates at horizontal beam lines and vertical irradiation thimbles.

  3. HFBR handbook, 1992: High flux beam reactor

    SciTech Connect (OSTI)

    Axe, J.D.; Greenberg, R.

    1992-10-01

    Welcome to the High Flux Beam Reactor (HFBR), one of the world premier neutron research facilities. This manual is intended primarily to acquaint outside users (and new Brookhaven staff members) with (almost) everything they need to know to work at the HFBR and to help make the stay at Brookhaven pleasant as well as profitable. Safety Training Programs to comply with US Department of Energy (DOE) mandates are in progress at BNL. There are several safety training requirements which must be met before users can obtain unescorted access to the HFBR. The Reactor Division has prepared specific safety training manuals which are to be sent to experimenters well in advance of their expected arrival at BNL to conduct experiments. Please familiarize yourself with this material and carefully pay strict attention to all the safety and security procedures that are in force at the HFBR. Not only your safety, but the continued operation of the facility, depends upon compliance.

  4. Temperature measurements during high flux ion beam irradiations

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

    Crespillo, Miguel L.; Graham, Joseph T.; Zhang, Yanwen; Weber, William J.

    2016-02-16

    A systematic study of the ion beam heating effect was performed in a temperature range of –170 to 900 °C using a 10 MeV Au3+ ion beam and a Yttria stabilized Zirconia (YSZ) sample at a flux of 5.5 × 1012 cm–2 s–1. Different geometric configurations of beam, sample, thermocouple positioning, and sample holder were compared to understand the heat/charge transport mechanisms responsible for the observed temperature increase. The beam heating exhibited a strong dependence on the background (initial) sample temperature with the largest temperature increases occurring at cryogenic temperatures and decreasing with increasing temperature. Comparison with numerical calculations suggestsmore » that the observed heating effect is, in reality, a predominantly electronic effect and the true temperature rise is small. Furthermore, a simple model was developed to explain this electronic effect in terms of an electrostatic potential that forms during ion irradiation. Such an artificial beam heating effect is potentially problematic in thermostated ion irradiation and ion beamanalysis apparatus, as the operation of temperature feedback systems can be significantly distorted by this effect.« less

  5. Radiation dosimetry at the BNL High Flux Beam Reactor

    SciTech Connect (OSTI)

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

    1998-02-01

    The HFBR is a heavy water, D{sub 2}O, cooled and moderated reactor with twenty-eight fuel elements containing a maximum of 9.8 kilograms of {sup 235}U. The core is 53 cm high and 48 cm in diameter and has an active volume of 97 liters. The HFBR, which was designed to operate at forty mega-watts, 40 NW, was upgraded to operate at 60 NW. Since 1991, it has operated at 30 MW. In a normal 30 MW operating cycle the HFBR operates 24 hours a day for thirty days, with a six to fourteen day shutdown period for refueling and maintenance work. While most reactors attempts to minimize the escape of neutrons from the core, the HFBR`s D{sub 2}O design allows the thermal neutron flux to peak in the reflector region and maximizes the number of thermal neutrons available to nine horizontal external beams, H-1 to H-9. The HFBR neutron dosimetry effort described here compares measured and calculated energy dependent neutron and gamma ray flux densities and/or dose rates at horizontal beam lines and vertical irradiation thimbles.

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

    DOE Patents [OSTI]

    Shu, Deming; Kuzay, Tuncer M.

    1995-01-01

    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. Measurements and model calculations of radiative fluxes for the Cabauw

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

    Experimental Site for Atmospheric Research, the Netherlands Measurements and model calculations of radiative fluxes for the Cabauw Experimental Site for Atmospheric Research, the Netherlands Knap, Wouter Royal Netherlands Meteorological Institute KNMI Los, Alexander KNMI Boers, Reinout KNMI Category: Radiation The Cabauw Experimental Site for Atmospheric Research (CESAR), the Netherlands (52.0N, 4.9E), contains an extensive set of instruments for atmospheric research, such as radar, lidar

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

    SciTech Connect (OSTI)

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

    1994-05-01

    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. Errors in response calculations for beams

    SciTech Connect (OSTI)

    Wada, H.; Wurburton, G.B.

    1985-05-01

    When the finite element method is used to idealize a structure, its dynamic response can be determined from the governing matrix equation by the normal mode method or by one of the many approximate direct integration methods. In either method the approximate data of the finite element idealization are used, but further assumptions are introduced by the direct integration scheme. It is the purpose of this paper to study these errors for a simple structure. The transient flexural vibrations of a uniform cantilever beam, which is subjected to a transverse force at the free end, are determined by the Laplace transform method. Comparable responses are obtained for a finite element idealization of the beam, using the normal mode and Newmark average acceleration methods; the errors associated with the approximate methods are studied. If accuracy has priority and the quantity of data is small, the normal mode method is recommended; however, if the quantity of data is large, the Newmark method is useful.

  10. The wave energy flux of high frequency diffracting beams in complex geometrical optics

    SciTech Connect (OSTI)

    Maj, Omar; Poli, Emanuele; Mariani, Alberto; Farina, Daniela

    2013-04-15

    We consider the construction of asymptotic solutions of Maxwell's equations for a diffracting wave beam in the high frequency limit and address the description of the wave energy flux transported by the beam. With this aim, the complex eikonal method is applied. That is a generalization of the standard geometrical optics method in which the phase function is assumed to be complex valued, with the non-negative imaginary part accounting for the finite width of the beam cross section. In this framework, we propose an argument which simplifies significantly the analysis of the transport equation for the wave field amplitude and allows us to derive the wave energy flux. The theoretical analysis is illustrated numerically for the case of electron cyclotron beams in tokamak plasmas by using the GRAY code [D. Farina, Fusion Sci. Technol. 52, 154 (2007)], which is based upon the complex eikonal theory. The results are compared to those of the paraxial beam tracing code TORBEAM [E. Poli et al., Comput. Phys. Commun. 136, 90 (2001)], which provides an independent calculation of the energy flow.

  11. Linear beam-beam tune shift calculations for the Tevatron Collider

    SciTech Connect (OSTI)

    Johnson, D.

    1989-01-12

    A realistic estimate of the linear beam-beam tune shift is necessary for the selection of an optimum working point in the tune diagram. Estimates of the beam-beam tune shift using the ''Round Beam Approximation'' (RBA) have over estimated the tune shift for the Tevatron. For a hadron machine with unequal lattice functions and beam sizes, an explicit calculation using the beam size at the crossings is required. Calculations for various Tevatron lattices used in Collider operation are presented. Comparisons between the RBA and the explicit calculation, for elliptical beams, are presented. This paper discusses the calculation of the linear tune shift using the program SYNCH. Selection of a working point is discussed. The magnitude of the tune shift is influenced by the choice of crossing points in the lattice as determined by the pbar ''cogging effects''. Also discussed is current cogging procedures and presents results of calculations for tune shifts at various crossing points in the lattice. Finally, a comparison of early pbar tune measurements with the present linear tune shift calculations is presented. 17 refs., 13 figs., 3 tabs.

  12. Ray tracing flux calculation for the small and wide angle x-ray...

    Office of Scientific and Technical Information (OSTI)

    Ray tracing flux calculation for the small and wide angle x-ray scattering diffraction station at the SESAME synchrotron radiation facility Citation Details In-Document Search ...

  13. Plasma focus ion beam fluence and fluxFor 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)

    2013-06-15

    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.

  14. Fast optimization and dose calculation in scanned ion beam therapy

    SciTech Connect (OSTI)

    Hild, S.; Graeff, C.; Trautmann, J.; Kraemer, M.; Zink, K.; Durante, M.; Bert, C.

    2014-07-15

    Purpose: Particle therapy (PT) has advantages over photon irradiation on static tumors. An increased biological effectiveness and active target conformal dose shaping are strong arguments for PT. However, the sensitivity to changes of internal geometry complicates the use of PT for moving organs. In case of interfractionally moving objects adaptive radiotherapy (ART) concepts known from intensity modulated radiotherapy (IMRT) can be adopted for PT treatments. One ART strategy is to optimize a new treatment plan based on daily image data directly before a radiation fraction is delivered [treatment replanning (TRP)]. Optimizing treatment plans for PT using a scanned beam is a time consuming problem especially for particles other than protons where the biological effective dose has to be calculated. For the purpose of TRP, fast optimization and fast dose calculation have been implemented into the GSI in-house treatment planning system (TPS) TRiP98. Methods: This work reports about the outcome of a code analysis that resulted in optimization of the calculation processes as well as implementation of routines supporting parallel execution of the code. To benchmark the new features, the calculation time for therapy treatment planning has been studied. Results: Compared to the original version of the TPS, calculation times for treatment planning (optimization and dose calculation) have been improved by a factor of 10 with code optimization. The parallelization of the TPS resulted in a speedup factor of 12 and 5.5 for the original version and the code optimized version, respectively. Hence the total speedup of the new implementation of the authors' TPS yielded speedup factors up to 55. Conclusions: The improved TPS is capable of completing treatment planning for ion beam therapy of a prostate irradiation considering organs at risk in this has been overseen in the review process. Also see below 6 min.

  15. Calculates Flux and Dose Rate from the Scattering of Radiation in Air.

    Energy Science and Technology Software Center (OSTI)

    1990-08-01

    Version 00 The program LSHINSE is used to calculate flux and dose rate caused by gamma radiation emanating from a point source and being scattered in the surrounding air.

  16. Supplementary neutron-flux calculations for the ORNL Pool Critical Assembly Pressure Vessel Facility

    SciTech Connect (OSTI)

    Maudlin, P.J.; Maerker, R.E.

    1982-01-01

    A three-dimensional Monte Carlo calculation using the MORSE code was performed to validate a procedure previously adopted in the ORNL discrete ordinate analysis of measurements made in the ORNL Pool Critical Assembly Pressure Vessel Facility. The results of these flux calculations agree, within statistical undertainties of about 5%, with those obtained from a discrete ordinate analysis employing the same procedure. This study therefore concludes that the procedure for combining several one- and two-dimensional discrete ordinate calculations into a three-dimensional flux is sufficiently accurate that it does not account for the existing discrepancies observed between calculations and measurements in this facility.

  17. ORBIT : BEAM DYNAMICS CALCULATIONS FOR HIGH - INTENSITY RINGS.

    SciTech Connect (OSTI)

    HOLMES,J.A.; DANILOV,V.; GALAMBOS,J.; SHISHLO,A.; COUSINEAU,S.; CHOU,W.; MICHELOTTI,L.; OSTIGUY,F.; WEI,J.

    2002-06-03

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK the introduction of a treatment magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings.

  18. BOXER: Fine-flux Cross Section Condensation, 2D Few Group Diffusion and Transport Burnup Calculations

    Energy Science and Technology Software Center (OSTI)

    2010-02-01

    Neutron transport, calculation of multiplication factor and neutron fluxes in 2-D configurations: cell calculations, 2-D diffusion and transport, and burnup. Preparation of a cross section library for the code BOXER from a basic library in ENDF/B format (ETOBOX).

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

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-10-22

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

  1. 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

    2010-12-15

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

  2. RADIATION DOSIMETRY AT THE BNL HIGH FLUX BEAM REACTOR AND MEDICAL RESEARCH REACTOR.

    SciTech Connect (OSTI)

    HOLDEN,N.E.

    1999-09-10

    RADIATION DOSIMETRY MEASUREMENTS HAVE BEEN PERFORMED OVER A PERIOD OF MANY YEARS AT THE HIGH FLUX BEAM REACTOR (HFBR) AND THE MEDICAL RESEARCH REACTOR (BMRR) AT BROOKHAVEN NATIONAL LABORATORY TO PROVIDE INFORMATION ON THE ENERGY DISTRIBUTION OF THE NEUTRON FLUX, NEUTRON DOSE RATES, GAMMA-RAY FLUXES AND GAMMA-RAY DOSE RATES. THE MCNP PARTICLE TRANSPORT CODE PROVIDED MONTE CARLO RESULTS TO COMPARE WITH VARIOUS DOSIMETRY MEASUREMENTS PERFORMED AT THE EXPERIMENTAL PORTS, AT THE TREATMENT ROOMS AND IN THE THIMBLES AT BOTH HFBR AND BMRR.

  3. Calculations Of Damage To Rotating Targets Under Intense Beams...

    Office of Scientific and Technical Information (OSTI)

    modest melting point andor high sputtering yield material will eventually melt or destroy the target. Defocused or 'wobbled' beams enhance target survival only to a modest degree. ...

  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

    2010-07-09

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

    DOE Patents [OSTI]

    Lasche, G.P.

    1983-09-29

    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.

  6. Development of Aerosol Models for Radiative Flux Calculations at ARM Sites

    SciTech Connect (OSTI)

    Ogren, John A.; Dutton, Ellsworth G.; McComiskey, Allison C.

    2006-09-30

    The direct radiative forcing (DRF) of aerosols, the change in net radiative flux due to aerosols in non-cloudy conditions, is an essential quantity for understanding the human impact on climate change. Our work has addressed several key issues that determine the accuracy, and identify the uncertainty, with which aerosol DRF can be modeled. These issues include the accuracy of several radiative transfer models when compared to measurements and to each other in a highly controlled closure study using data from the ARM 2003 Aerosol IOP. The primary focus of our work has been to determine an accurate approach to assigning aerosol properties appropriate for modeling over averaged periods of time and space that represent the observed regional variability of these properties. We have also undertaken a comprehensive analysis of the aerosol properties that contribute most to uncertainty in modeling aerosol DRF, and under what conditions they contribute the most uncertainty. Quantification of these issues enables the community to better state accuracies of radiative forcing calculations and to concentrate efforts in areas that will decrease uncertainties in these calculations in the future.

  7. 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

    2010-12-15

    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

  8. 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

    2010-11-03

    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

  9. High active nitrogen flux growth of GaN by plasma assisted molecular beam epitaxy

    SciTech Connect (OSTI)

    McSkimming, Brian M. Speck, James S.; Chaix, Catherine

    2015-09-15

    In the present study, the authors report on a modified Riber radio frequency (RF) nitrogen plasma source that provides active nitrogen fluxes more than 30 times higher than those commonly used for plasma assisted molecular beam epitaxy (PAMBE) growth of gallium nitride (GaN) and thus a significantly higher growth rate than has been previously reported. GaN films were grown using N{sub 2} gas flow rates between 5 and 25 sccm while varying the plasma source's RF forward power from 200 to 600 W. The highest growth rate, and therefore the highest active nitrogen flux, achieved was ∼7.6 μm/h. For optimized growth conditions, the surfaces displayed a clear step-terrace structure with an average RMS roughness (3 × 3 μm) on the order of 1 nm. Secondary ion mass spectroscopy impurity analysis demonstrates oxygen and hydrogen incorporation of 1 × 10{sup 16} and ∼5 × 10{sup 17}, respectively. In addition, the authors have achieved PAMBE growth of GaN at a substrate temperature more than 150 °C greater than our standard Ga rich GaN growth regime and ∼100 °C greater than any previously reported PAMBE growth of GaN. This growth temperature corresponds to GaN decomposition in vacuum of more than 20 nm/min; a regime previously unattainable with conventional nitrogen plasma sources. Arrhenius analysis of the decomposition rate shows that samples with a flux ratio below stoichiometry have an activation energy greater than decomposition of GaN in vacuum while samples grown at or above stoichiometry have decreased activation energy. The activation energy of decomposition for GaN in vacuum was previously determined to be ∼3.1 eV. For a Ga/N flux ratio of ∼1.5, this activation energy was found to be ∼2.8 eV, while for a Ga/N flux ratio of ∼0.5, it was found to be ∼7.9 eV.

  10. Ion species control in high flux deuterium plasma beams produced by a linear plasma generator

    SciTech Connect (OSTI)

    Luo, G.-N.; Shu, W.M.; Nakamura, H.; O'Hira, S.; Nishi, M.

    2004-11-01

    The ion species ratios in low energy high flux deuterium plasma beams formed in a linear plasma generator were measured by a quadrupole mass spectrometer. And the species control in the plasma generator was evaluated by changing the operational parameters like neutral pressure, arc current, and axial magnetic confinement to the plasma column. The measurements reveal that the lower pressures prefer to form more D{sup +} ions, and the medium magnetic confinement at the higher pressures results in production of more D{sub 2}{sup +}, while the stronger confinement and/or larger arc current are helpful to D{sub 2}{sup +} conversion into D{sub 3}{sup +}. Therefore, the ion species can be controlled by adjusting the operational parameters of the plasma generator. With suitable adjustment, we can achieve plasma beams highly enriched with a single species of D{sup +}, D{sub 2}{sup +}, or D{sub 3}{sup +}, to a ratio over 80%. It has been found that the axial magnetic configuration played a significant role in the formation of D{sub 3}{sup +} within the experimental pressure range.

  11. SU-E-T-386: A Monte Carlo Dose Calculation Framework for Electron Beams On Varian TrueBeam

    SciTech Connect (OSTI)

    Rodrigues, A; Yin, F; Wu, Q; Sawkey, D

    2014-06-01

    Purpose: The design of the linac head is different for TrueBeam than Clinac, and there are differences in measured dose distributions in water phantoms between TrueBeam and Clinac for electron beams. Therefore, MC models for Clinac may not be applied directly to the Truebeam linac. The purpose of this study is to validate a Monte Carlo (MC) dose calculation framework for electron beams on Varian TrueBeam with phase space files provided by Varian. Methods: The particle histories from the phase space file were used as input for the down-stream simulation including jaws, applicators, and water phantom. MC packages BEAMnrc/DOSYXZnrc were used. The down-stream beam components were modeled according to manufacturer specifications and the dose distributions were compared with the measured data of standard cones. The measurements were performed in a water phantom with a p-type electron field diode (diameter 0.2cm) and ion chamber (CC13). Depth dose and orthogonal profiles at depths defined by R{sub 1} {sub 0} {sub 0}, R{sub 5} {sub 0}, Rp were compared. Results: Preliminary results for a 16 MeV phase space and 10x10, 15x15, and 20x20 cm{sup 2} applicator are presented. Simulations were run for a statistical uncertainty of <2% at depth of maximum dose for a voxel resolution of 0.5x0.5x0.2cm{sup 2}. Dose and range differences for the PDD profiles were within 2% and 1 mm, respectively. Dose differences within the central 80% of the beam width for the orthogonal profiles at depth of maximum dose were less than 2% for the 10x10, 15x15, and 20x20 cm{sup 2} applicator, respectively. Conclusion: Varian electron phase space files simulations are in agreement with measured commissioning data. These phase space files can be used in the simulation of TrueBeam linacs, and will provide reproducibility across publications. Analyses for all electron energies and standard applicators are under way and results will be included in the presentation.

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

    SciTech Connect (OSTI)

    Vandervoort, Eric J. Cygler, Joanna E.; The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5; Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 ; Tchistiakova, Ekaterina; Department of Medical Biophysics, University of Toronto, Ontario M5G 2M9; Heart and Stroke Foundation Centre for Stroke Recovery, Sunnybrook Research Institute, University of Toronto, Ontario M4N 3M5 ; La Russa, Daniel J.; The Faculty of Medicine, The University of Ottawa, Ottawa, Ontario K1H 8M5

    2014-02-15

    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.

  13. A Monte Carlo simulation framework for electron beam dose calculations using Varian phase space files for TrueBeam Linacs

    SciTech Connect (OSTI)

    Rodrigues, Anna; Yin, Fang-Fang; Wu, Qiuwen; Sawkey, Daren

    2015-05-15

    Purpose: To develop a framework for accurate electron Monte Carlo dose calculation. In this study, comprehensive validations of vendor provided electron beam phase space files for Varian TrueBeam Linacs against measurement data are presented. Methods: In this framework, the Monte Carlo generated phase space files were provided by the vendor and used as input to the downstream plan-specific simulations including jaws, electron applicators, and water phantom computed in the EGSnrc environment. The phase space files were generated based on open field commissioning data. A subset of electron energies of 6, 9, 12, 16, and 20 MeV and open and collimated field sizes 3 × 3, 4 × 4, 5 × 5, 6 × 6, 10 × 10, 15 × 15, 20 × 20, and 25 × 25 cm{sup 2} were evaluated. Measurements acquired with a CC13 cylindrical ionization chamber and electron diode detector and simulations from this framework were compared for a water phantom geometry. The evaluation metrics include percent depth dose, orthogonal and diagonal profiles at depths R{sub 100}, R{sub 50}, R{sub p}, and R{sub p+} for standard and extended source-to-surface distances (SSD), as well as cone and cut-out output factors. Results: Agreement for the percent depth dose and orthogonal profiles between measurement and Monte Carlo was generally within 2% or 1 mm. The largest discrepancies were observed within depths of 5 mm from phantom surface. Differences in field size, penumbra, and flatness for the orthogonal profiles at depths R{sub 100}, R{sub 50}, and R{sub p} were within 1 mm, 1 mm, and 2%, respectively. Orthogonal profiles at SSDs of 100 and 120 cm showed the same level of agreement. Cone and cut-out output factors agreed well with maximum differences within 2.5% for 6 MeV and 1% for all other energies. Cone output factors at extended SSDs of 105, 110, 115, and 120 cm exhibited similar levels of agreement. Conclusions: We have presented a Monte Carlo simulation framework for electron beam dose calculations for

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

    SciTech Connect (OSTI)

    Muir, B. R.; Rogers, D. W. O.

    2014-11-01

    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

  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.; Rebai, M.; Cippo, E. Perelli; Gorini, G.; Cazzaniga, C.; Palma, M. Dalla; Pasqualotto, R.; Tollin, M.; Grosso, G.; Muraro, A.; Murtas, F.; Claps, G.; Cavenago, M.

    2014-08-21

    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.

    2012-05-20

    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. Calculating survival curves in spread-peaks of heavy ion beams and comparison with experiment

    SciTech Connect (OSTI)

    Curtis, S.B.; Chu, W.T.; Llacer, J.; Renner, T.R.; Rodriguez, A.; Yang, T.C.H.

    1995-08-01

    In preparing for treating patients with high-energy ion beams, it is important first to determine the composition of the beam, that is, the relative mixes of the various primary and secondary particles and their LET spectra, and secondly to estimate the cell killing expected during a treatment schedule. This requires measurements of the beam composition at various depths through the spread-peak region, and a calculation of cell survival using a cell-killing model designed to accommodate the mixed LET nature of the beam in the spread-peak region. This talk presents results of an experiment in which a particle identification telescope, the BEPKLET, was used to measure the LET spectra of the primary and secondary particles at two positions in a 12-cm-spread-peak of a 585 MeV/amu neon ion beam at the Bevalac. Cell survival measurements were made at the same positions at which the LET-spectra were measured. The survival curves obtained were compared with calculations using the LPL (Lethal, Potentially Lethal) model of cell-killing. Results agree quite well at doses up to about 4 Gy. A quantity proportional to the RBE at 10% survival, when plotted against dose-averaged LET for a number of different beams and energies, appears to be a fairly good predictor of biological effect. This would not be expected if the difference in biological effect due to differences in track structure between various ions at the same LET played a significant role in modifying cell-killing in the range of LETs covered by this experiment.

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

    SciTech Connect (OSTI)

    Muir, B. R. Rogers, D. W. O.

    2013-12-15

    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

  19. 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; Sanchez del Rio, M.; Hoorani, H.

    2009-09-15

    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).

  20. High-flux low-divergence positron beam generation from ultra-intense laser irradiated a tapered hollow target

    SciTech Connect (OSTI)

    Liu, Jian-Xun; Ma, Yan-Yun; Zhao, Jun; Yu, Tong-Pu Yang, Xiao-Hu; Gan, Long-Fei; Zhang, Guo-Bo; Yan, Jian-Feng; Zhuo, Hong-Bin; Liu, Jin-Jin; Zhao, Yuan; Kawata, Shigeo

    2015-10-15

    By using two-dimensional particle-in-cell simulations, we demonstrate high-flux dense positrons generation by irradiating an ultra-intense laser pulse onto a tapered hollow target. By using a laser with an intensity of 4 × 10{sup 23 }W/cm{sup 2}, it is shown that the Breit-Wheeler process dominates the positron production during the laser-target interaction and a positron beam with a total number >10{sup 15} is obtained, which is increased by five orders of magnitude than in the previous work at the same laser intensity. Due to the focusing effect of the transverse electric fields formed in the hollow cone wall, the divergence angle of the positron beam effectively decreases to ∼15° with an effective temperature of ∼674 MeV. When the laser intensity is doubled, both the positron flux (>10{sup 16}) and temperature (963 MeV) increase, while the divergence angle gets smaller (∼13°). The obtained high-flux low-divergence positron beam may have diverse applications in science, medicine, and engineering.

  1. Self-corrected Sensors Based On Atomic Absorption Spectroscopy For Atom Flux Measurements In Molecular Beam Epitaxy

    SciTech Connect (OSTI)

    Du, Yingge; Droubay, Timothy C.; Liyu, Andrey V.; Li, Guosheng; Chambers, Scott A.

    2014-04-24

    A high sensitivity atom flux sensor based on atomic absorption spectroscopy has been designed and implemented to control electron beam evaporators and effusion cells in a molecular beam epitaxy system. Using a high-resolution spectrometer and a two-dimensional charge coupled device (CCD) detector in a double-beam configuration, we employ a non-resonant line or a resonant line with lower absorbance from the same hollow cathode lamp as the reference for nearly perfect background correction and baseline drift removal. This setup also significantly shortens the warm-up time needed compared to other sensor technologies and drastically reduces the noise coming from the surrounding environment. In addition, the high-resolution spectrometer allows the most sensitive resonant line to be isolated and used to provide excellent signal-to-noise ratio.

  2. Self-corrected sensors based on atomic absorption spectroscopy for atom flux measurements in molecular beam epitaxy

    SciTech Connect (OSTI)

    Du, Y. E-mail: scott.chambers@pnnl.gov; Liyu, A. V.; Droubay, T. C.; Chambers, S. A. E-mail: scott.chambers@pnnl.gov; Li, G.

    2014-04-21

    A high sensitivity atom flux sensor based on atomic absorption spectroscopy has been designed and implemented to control electron beam evaporators and effusion cells in a molecular beam epitaxy system. Using a high-resolution spectrometer and a two-dimensional charge coupled device detector in a double-beam configuration, we employ either a non-resonant line or a resonant line with low cross section from the same hollow cathode lamp as the reference for nearly perfect background correction and baseline drift removal. This setup also significantly shortens the warm-up time needed compared to other sensor technologies and drastically reduces the noise coming from the surrounding environment. In addition, the high-resolution spectrometer allows the most sensitive resonant line to be isolated and used to provide excellent signal-to-noise ratio.

  3. Ion beam measurement of deuterium in palladium and calculation of hydrogen isotope separation factors

    SciTech Connect (OSTI)

    Gullinger, T.R.; Kelly, M.J.; Knapp, J.A.; Walsh, D.S.; Doyle, B.L. )

    1991-08-01

    In this paper, the authors demonstrate a new technique for measuring hydrogen isotope separation factors in hydrogen-absorbing metals. Using external ion beam nuclear reaction analysis of metal electrodes in an operating electrochemical cell, the authors monitor in situ the deuterium content of the electrode. changing the deuterium/hydrogen ratio in the electrolyte changes the observed deuterium content of the metal electrode, and, assuming identical ultimate total metal loading for deuterium, hydrogen, and any mixture of deuterium and hydrogen, a simple calculation yields the separation factor.

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

    SciTech Connect (OSTI)

    Shibata, Y. Manabe, T.; Ohno, N.; Takagi, M.; Kajita, S.; Tsuchiya, H.; Morisaki, T.

    2014-09-15

    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. Calculating tumor trajectory and dose-of-the-day using cone-beam CT projections

    SciTech Connect (OSTI)

    Jones, Bernard L. Westerly, David; Miften, Moyed

    2015-02-15

    Purpose: Cone-beam CT (CBCT) projection images provide anatomical data in real-time over several respiratory cycles, forming a comprehensive picture of tumor movement. The authors developed and validated a method which uses these projections to determine the trajectory of and dose to highly mobile tumors during each fraction of treatment. Methods: CBCT images of a respiration phantom were acquired, the trajectory of which mimicked a lung tumor with high amplitude (up to 2.5 cm) and hysteresis. A template-matching algorithm was used to identify the location of a steel BB in each CBCT projection, and a Gaussian probability density function for the absolute BB position was calculated which best fit the observed trajectory of the BB in the imager geometry. Two modifications of the trajectory reconstruction were investigated: first, using respiratory phase information to refine the trajectory estimation (Phase), and second, using the Monte Carlo (MC) method to sample the estimated Gaussian tumor position distribution. The accuracies of the proposed methods were evaluated by comparing the known and calculated BB trajectories in phantom-simulated clinical scenarios using abdominal tumor volumes. Results: With all methods, the mean position of the BB was determined with accuracy better than 0.1 mm, and root-mean-square trajectory errors averaged 3.8% ± 1.1% of the marker amplitude. Dosimetric calculations using Phase methods were more accurate, with mean absolute error less than 0.5%, and with error less than 1% in the highest-noise trajectory. MC-based trajectories prevent the overestimation of dose, but when viewed in an absolute sense, add a small amount of dosimetric error (<0.1%). Conclusions: Marker trajectory and target dose-of-the-day were accurately calculated using CBCT projections. This technique provides a method to evaluate highly mobile tumors using ordinary CBCT data, and could facilitate better strategies to mitigate or compensate for motion during

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

    DOE Patents [OSTI]

    Lasche, G.P.

    1987-02-20

    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.

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

    DOE Patents [OSTI]

    Lasche, George P.

    1988-01-01

    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.

  8. SU-E-T-209: Independent Dose Calculation in FFF Modulated Fields with Pencil Beam Kernels Obtained by Deconvolution

    SciTech Connect (OSTI)

    Azcona, J; Burguete, J

    2014-06-01

    Purpose: To obtain the pencil beam kernels that characterize a megavoltage photon beam generated in a FFF linac by experimental measurements, and to apply them for dose calculation in modulated fields. Methods: Several Kodak EDR2 radiographic films were irradiated with a 10 MV FFF photon beam from a Varian True Beam (Varian Medical Systems, Palo Alto, CA) linac, at the depths of 5, 10, 15, and 20cm in polystyrene (RW3 water equivalent phantom, PTW Freiburg, Germany). The irradiation field was a 50 mm diameter circular field, collimated with a lead block. Measured dose leads to the kernel characterization, assuming that the energy fluence exiting the linac head and further collimated is originated on a point source. The three-dimensional kernel was obtained by deconvolution at each depth using the Hankel transform. A correction on the low dose part of the kernel was performed to reproduce accurately the experimental output factors. The kernels were used to calculate modulated dose distributions in six modulated fields and compared through the gamma index to their absolute dose measured by film in the RW3 phantom. Results: The resulting kernels properly characterize the global beam penumbra. The output factor-based correction was carried out adding the amount of signal necessary to reproduce the experimental output factor in steps of 2mm, starting at a radius of 4mm. There the kernel signal was in all cases below 10% of its maximum value. With this correction, the number of points that pass the gamma index criteria (3%, 3mm) in the modulated fields for all cases are at least 99.6% of the total number of points. Conclusion: A system for independent dose calculations in modulated fields from FFF beams has been developed. Pencil beam kernels were obtained and their ability to accurately calculate dose in homogeneous media was demonstrated.

  9. Two-dimensional DORT discrete ordinates X-Y geometry neutron flux calculations for the Halden Heavy Boiling Water Reactor core configurations

    SciTech Connect (OSTI)

    Slater, C.O.

    1990-07-01

    Results are reported for two-dimensional discrete ordinates, X-Y geometry calculations performed for seven Halden Heavy Boiling Water Reactor core configurations. The calculations were performed in support of an effort to reassess the neutron fluence received by the reactor vessel. Nickel foil measurement data indicated considerable underprediction of fluences by the previously used multigroup removal- diffusion method. Therefore, calculations by a more accurate method were deemed appropriate. For each core configuration, data are presented for (1) integral fluxes in the core and near the vessel wall, (2) neutron spectra at selected locations, (3) isoflux contours superimposed on the geometry models, (4) plots of the geometry models, and (5) input for the calculations. The initial calculations were performed with several mesh sizes. Comparisons of the results from these calculations indicated that the uncertainty in the calculated fluxes should be less than 10%. However, three-dimensional effects (such as axial asymmetry in the fuel loading) could contribute to much greater uncertainty in the calculated neutron fluxes. 7 refs., 22 figs., 11 tabs.

  10. Calculation

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

    Calculation of resistive magnetohydrodynamics and two-fluid tearing modes by example of reversed-field-pinch-like plasma V. A. Svidzinski and H. Li Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA ͑Received 26 November 2007; accepted 7 April 2008; published online 15 May 2008͒ An algorithm suitable for numerical solution of linear eigenmode problems in resistive magnetohydrodynamics ͑MHD͒ and two-fluid MHD models without prior approximations is presented. For these plasma

  11. Development of a golden beam data set for the commissioning of a proton double-scattering system in a pencil-beam dose calculation algorithm

    SciTech Connect (OSTI)

    Slopsema, R. L. Flampouri, S.; Yeung, D.; Li, Z.; Lin, L.; McDonough, J. E.; Palta, J.

    2014-09-15

    Purpose: The purpose of this investigation is to determine if a single set of beam data, described by a minimal set of equations and fitting variables, can be used to commission different installations of a proton double-scattering system in a commercial pencil-beam dose calculation algorithm. Methods: The beam model parameters required to commission the pencil-beam dose calculation algorithm (virtual and effective SAD, effective source size, and pristine-peak energy spread) are determined for a commercial double-scattering system. These parameters are measured in a first room and parameterized as function of proton energy and nozzle settings by fitting four analytical equations to the measured data. The combination of these equations and fitting values constitutes the golden beam data (GBD). To determine the variation in dose delivery between installations, the same dosimetric properties are measured in two additional rooms at the same facility, as well as in a single room at another facility. The difference between the room-specific measurements and the GBD is evaluated against tolerances that guarantee the 3D dose distribution in each of the rooms matches the GBD-based dose distribution within clinically reasonable limits. The pencil-beam treatment-planning algorithm is commissioned with the GBD. The three-dimensional dose distribution in water is evaluated in the four treatment rooms and compared to the treatment-planning calculated dose distribution. Results: The virtual and effective SAD measurements fall between 226 and 257 cm. The effective source size varies between 2.4 and 6.2 cm for the large-field options, and 1.0 and 2.0 cm for the small-field options. The pristine-peak energy spread decreases from 1.05% at the lowest range to 0.6% at the highest. The virtual SAD as well as the effective source size can be accurately described by a linear relationship as function of the inverse of the residual energy. An additional linear correction term as function of

  12. 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.

    2011-06-24

    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.

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

    SciTech Connect (OSTI)

    Dooling, J.; Accelerator Systems Division

    2010-11-01

    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

  14. Calculation of the Beam Field in the LCLS Bunch Length Monitor

    SciTech Connect (OSTI)

    Stupakov, G.; Ding, Y.; Huang, Z.; /SLAC

    2006-06-07

    Maintaining a stable bunch length and peak current is a critical step for the reliable operation of a SASE based x-ray source. In the LCLS, relative bunch length monitors (BLM) right after both bunch compressors are proposed based on the coherent radiation generated by the short electron bunch. Due to its diagnostic setup, the standard far field synchrotron radiation formula and well-developed numerical codes do not apply for the analysis of the BLM performance. In this paper, we develop a calculation procedure to take into account the near field effect, the effect of a short bending magnet, and the diffraction effect of the radiation transport optics. We find the frequency response of the BLM after the first LCLS bunch compressor and discuss its expected performance.

  15. Exact and variational calculations of eigenmodes for three-dimensional free electron laser interaction with a warm electron beam

    SciTech Connect (OSTI)

    Xie, M.

    1995-12-31

    I present an exact calculation of free-electron-laser (FEL) eigenmodes (fundamental as well as higher order modes) in the exponential-gain regime. These eigenmodes specify transverse profiles and exponential growth rates of the laser field, and they are self-consistent solutions of the coupled Maxwell-Vlasov equations describing the FEL interaction taking into account the effects due to energy spread, emittance and betatron oscillations of the electron beam, and diffraction and guiding of the laser field. The unperturbed electron distribution is assumed to be of Gaussian shape in four dimensional transverse phase space and in the energy variable, but uniform in longitudinal coordinate. The focusing of the electron beam is assumed to be matched to the natural wiggler focusing in both transverse planes. With these assumptions the eigenvalue problem can be reduced to a numerically manageable integral equation and solved exactly with a kernel iteration method. An approximate, but more efficient solution of the integral equation is also obtained for the fundamental mode by a variational technique, which is shown to agree well with the exact results. Furthermore, I present a handy formula, obtained from interpolating the numerical results, for a quick calculation of FEL exponential growth rate. Comparisons with simulation code TDA will also be presented. Application of these solutions to the design and multi-dimensional parameter space optimization for an X-ray free electron laser driven by SLAC linac will be demonstrated. In addition, a rigorous analysis of transverse mode degeneracy and hence the transverse coherence of the X-ray FEL will be presented based on the exact solutions of the higher order guided modes.

  16. SU-E-T-586: Field Size Dependence of Output Factor for Uniform Scanning Proton Beams: A Comparison of TPS Calculation, Measurement and Monte Carlo Simulation

    SciTech Connect (OSTI)

    Zheng, Y; Singh, H; Islam, M

    2014-06-01

    Purpose: Output dependence on field size for uniform scanning beams, and the accuracy of treatment planning system (TPS) calculation are not well studied. The purpose of this work is to investigate the dependence of output on field size for uniform scanning beams and compare it among TPS calculation, measurements and Monte Carlo simulations. Methods: Field size dependence was studied using various field sizes between 2.5 cm diameter to 10 cm diameter. The field size factor was studied for a number of proton range and modulation combinations based on output at the center of spread out Bragg peak normalized to a 10 cm diameter field. Three methods were used and compared in this study: 1) TPS calculation, 2) ionization chamber measurement, and 3) Monte Carlos simulation. The XiO TPS (Electa, St. Louis) was used to calculate the output factor using a pencil beam algorithm; a pinpoint ionization chamber was used for measurements; and the Fluka code was used for Monte Carlo simulations. Results: The field size factor varied with proton beam parameters, such as range, modulation, and calibration depth, and could decrease over 10% from a 10 cm to 3 cm diameter field for a large range proton beam. The XiO TPS predicted the field size factor relatively well at large field size, but could differ from measurements by 5% or more for small field and large range beams. Monte Carlo simulations predicted the field size factor within 1.5% of measurements. Conclusion: Output factor can vary largely with field size, and needs to be accounted for accurate proton beam delivery. This is especially important for small field beams such as in stereotactic proton therapy, where the field size dependence is large and TPS calculation is inaccurate. Measurements or Monte Carlo simulations are recommended for output determination for such cases.

  17. 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.

    2012-01-13

    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

  18. Heat Flux Calculation and Problem of Flaking of Boron Carbide Coatings on the Faraday Screen of the ICRH Antennas During Tore Supra High Power, Long Pulse Operation

    SciTech Connect (OSTI)

    Corre, Y.; Lipa, M.; Agarici, G.; Basiuk, V.; Colas, L.; Courtois, X.; Dumont, R. J.; Ekedahl, A.; Gardarein, J. L.; Klepper, C Christopher; Martin, V.; Moncada, V.; Portafaix, C.; Rigollet, F.; Tawizgant, R.; Travere, J. M.; Valliez, K.

    2011-01-01

    Reliable and repetitive high power and long pulse tokamak operation is strongly dependant of the ability to secure the Plasma Facing Components (PFCs). In Tore Supra, a network of 7 infrared (IR) video cameras is routinely used to prevent PFCs overheating and damage in selected regions. Real time feedback control and offline analysis are essential for basic protection and understanding of abnormal thermal events. One important limitation detected by the IR real time feed-back loop during high power RF operation (injected power of 9.5 MW over 26 s and 12 MW over 10 s have been achieved respectively in 2006 and 2008) is due to the interaction between fast ions which increase the power flux density and flaking of the boron carbide coatings on the Faraday screen box of the ICRH antennas. An IR-based experimental procedure is proposed in order to detect new flakes during plasma operation. The thermal response of the B4C coating is studied with and without flaking during plasma operation. The experimental heat flux deposited by fast ion losses on the Faraday screen is calculated for high (3.8 T) and low magnetic field (2 T) during high RF power operation (with fundamental hydrogen minority and second harmonic ICRH heating schemes respectively). The paper addresses both thermal science issues applied to machine protection and limitation due to fast ions issues during high RF power, long pulse operation. Safety margin to critical heat flux and number of fatigue cycles under heat load are presented in the paper.

  19. 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

    2011-11-30

    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).

  20. Design of a High Resolution and High Flux Beam line for VUV Angle-Resolved Photoemission at UVSOR-II

    SciTech Connect (OSTI)

    Kimura, Shin-ichi; Ito, Takahiro; Nakamura, Eiken; Hosaka, Masahito; Katoh, Masahiro

    2007-01-19

    A high-energy-resolution angle-resolved photoemission beamline in the vacuum-ultraviolet (VUV) region has been designed for a 750 MeV synchrotron light source UVSOR-II. The beamline equips an APPLE-II-type undulator with the horizontally/vertically linear and right/left circular polarizations, a modified Wadsworth-type monochromator and a high-resolution photoelectron analyzer. The monochromator covers the photon energy range of 6 - 40 eV. The energy resolution (hv/{delta}hv) and the photon flux on samples are expected to be 2 x 104 and 1012 photons/sec at 10 eV, 4 x 104 and 5 x 1011 photons/sec at 20 eV, and 6 x 104 and 1011 photons/sec at 40 eV, respectively. The beamline provides the high-resolution angle-resolved photoemission spectroscopy less than 1 meV in the whole VUV energy range.

  1. SU-E-T-71: Commissioning and Acceptance Testing of a Commercial Monte Carlo Electron Dose Calculation Model (eMC) for TrueBeam

    SciTech Connect (OSTI)

    Sheu, R; Tseng, T; Powers, A; Lo, Y

    2014-06-01

    Purpose: To provide commissioning and acceptance test data of the Varian Eclipse electron Monte Carlo model (eMC v.11) for TrueBeam linac. We also investigated the uncertainties in beam model parameters and dose calculation results for different geometric configurations. Methods: For beam commissioning, PTW CC13 thimble chamber and IBA Blue Phantom2 were used to collect PDD and dose profiles in air. Cone factors were measured with a parallel plate chamber (PTW N23342) in solid water. GafChromic EBT3 films were used for dose calculation verifications to compare with parallel plate chamber results in the following test geometries: oblique incident, extended distance, small cutouts, elongated cutouts, irregular surface, and heterogeneous layers. Results: Four electron energies (6e, 9e, 12e, and 15e) and five cones (66, 1010, 1515, 2020, and 2525) with standard cutouts were calculated for different grid sizes (1, 1.5,2, and 2.5 mm) and compared with chamber measurements. The results showed calculations performed with a coarse grid size underestimated the absolute dose. The underestimation decreased as energy increased. For 6e, the underestimation (max 3.3 %) was greater than the statistical uncertainty level (3%) and was systematically observed for all cone sizes. By using a 1mm grid size, all the calculation results agreed with measurements within 5% for all test configurations. The calculations took 21s and 46s for 6e and 15e (2.5mm grid size) respectively distributed on 4 calculation servants. Conclusion: In general, commissioning the eMC dose calculation model on TrueBeam is straightforward and thedose calculation is in good agreement with measurements for all test cases. Monte Carlo dose calculation provides more accurate results which improves treatment planning quality. However, the normal acceptable grid size (2.5mm) would cause systematic underestimation in absolute dose calculation for lower energies, such as 6e. Users need to be cautious in this

  2. Field calculations, single-particle tracking, and beam dynamics with space charge in the electron lens for the Fermilab Integrable Optics Test Accelerator

    SciTech Connect (OSTI)

    Noll, Daniel; Stancari, Giulio

    2015-11-17

    An electron lens is planned for the Fermilab Integrable Optics Test Accelerator as a nonlinear element for integrable dynamics, as an electron cooler, and as an electron trap to study space-charge compensation in rings. We present the main design principles and constraints for nonlinear integrable optics. A magnetic configuration of the solenoids and of the toroidal section is laid out. Singleparticle tracking is used to optimize the electron path. Electron beam dynamics at high intensity is calculated with a particle-in-cell code to estimate current limits, profile distortions, and the effects on the circulating beam. In the conclusions, we summarize the main findings and list directions for further work.

  3. DARK MATTER IN THE CLASSICAL DWARF SPHEROIDAL GALAXIES: A ROBUST CONSTRAINT ON THE ASTROPHYSICAL FACTOR FOR {gamma}-RAY FLUX CALCULATIONS

    SciTech Connect (OSTI)

    Walker, M. G.; Combet, C.; Hinton, J. A.; Maurin, D.; Wilkinson, M. I. E-mail: dmaurin@lspc.in2p3.fr

    2011-06-01

    We present a new analysis of the relative detectability of dark matter annihilation in the Milky Way's eight 'classical' dwarf spheroidal (dSph) satellite galaxies. Ours is similar to previous analyses in that we use Markov-Chain Monte Carlo techniques to fit dark matter halo parameters to empirical velocity dispersion profiles via the spherical Jeans equation, but more general in the sense that we do not adopt priors derived from cosmological simulations. We show that even without strong constraints on the shapes of dSph dark matter density profiles (we require only that the inner profile satisfies -liM{sub r {yields} 0} dln {rho}/dln r {<=} 1), we obtain a robust and accurate constraint on the astrophysical component of a prospective dark matter annihilation signal, provided that the integration angle is approximately twice the projected half-light radius of the dSph divided by distance to the observer, {alpha}{sub int} {approx} 2r{sub h} /d. Using this integration angle, which represents a compromise between maximizing prospective flux and minimizing uncertainty in the dSph's dark matter distribution, we calculate the relative detectability of the classical dSphs by ground- and space-based {gamma}-ray observatories.

  4. LCLS Spectral Flux Viewer

    Energy Science and Technology Software Center (OSTI)

    2005-10-25

    This application (FluxViewer) is a tool for displaying spectral flux data for the Linac Coherent Light Source (LCLS). This tool allows the user to view sliced spatial and energy distributions of the photons selected for specific energies and positions transverse to the beam axis.

  5. 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; Ahmad, Salahuddin

    2013-10-01

    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

  6. Study the sensitivity of dose calculation in prism treatment planning system using Monte Carlo simulation of 6 MeV electron beam

    SciTech Connect (OSTI)

    Hardiansyah, D.; Haryanto, F.; Male, S.

    2014-09-30

    Prism is a non-commercial Radiotherapy Treatment Planning System (RTPS) develop by Ira J. Kalet from Washington University. Inhomogeneity factor is included in Prism TPS dose calculation. The aim of this study is to investigate the sensitivity of dose calculation on Prism using Monte Carlo simulation. Phase space source from head linear accelerator (LINAC) for Monte Carlo simulation is implemented. To achieve this aim, Prism dose calculation is compared with EGSnrc Monte Carlo simulation. Percentage depth dose (PDD) and R50 from both calculations are observed. BEAMnrc is simulated electron transport in LINAC head and produced phase space file. This file is used as DOSXYZnrc input to simulated electron transport in phantom. This study is started with commissioning process in water phantom. Commissioning process is adjusted Monte Carlo simulation with Prism RTPS. Commissioning result is used for study of inhomogeneity phantom. Physical parameters of inhomogeneity phantom that varied in this study are: density, location and thickness of tissue. Commissioning result is shown that optimum energy of Monte Carlo simulation for 6 MeV electron beam is 6.8 MeV. This commissioning is used R50 and PDD with Practical length (R{sub p}) as references. From inhomogeneity study, the average deviation for all case on interest region is below 5 %. Based on ICRU recommendations, Prism has good ability to calculate the radiation dose in inhomogeneity tissue.

  7. Relative efficiency calculations of biological and physical systems exposed to charged particle beams through Monte Carlo simulation

    SciTech Connect (OSTI)

    Avila, Olga; Brandan, Maria-Ester

    1998-08-28

    A theoretical investigation of thermoluminescence response of Lithium Fluoride after heavy ion irradiation has been performed through Monte Carlo simulation of the energy deposition process. Efficiencies for the total TL signal of LiF irradiated with 0.7, 1.5 and 3 MeV protons and 3, 5.3 and 7.5 MeV helium ions have been calculated using the radial dose distribution profiles obtained from the MC procedure and applying Track Structure Theory and Modified Track Structure Theory. Results were compared with recent experimental data. The models correctly describe the observed decrease in efficiency as a function of the ion LET.

  8. SU-E-I-05: A Correction Algorithm for Kilovoltage Cone-Beam Computed Tomography Dose Calculations in Cervical Cancer Patients

    SciTech Connect (OSTI)

    Zhang, J; Zhang, W; Lu, J

    2015-06-15

    Purpose: To investigate the accuracy and feasibility of dose calculations using kilovoltage cone beam computed tomography in cervical cancer radiotherapy using a correction algorithm. Methods: The Hounsfield units (HU) and electron density (HU-density) curve was obtained for both planning CT (pCT) and kilovoltage cone beam CT (CBCT) using a CIRS-062 calibration phantom. The pCT and kV-CBCT images have different HU values, and if the HU-density curve of CBCT was directly used to calculate dose in CBCT images may have a deviation on dose distribution. It is necessary to normalize the different HU values between pCT and CBCT. A HU correction algorithm was used for CBCT images (cCBCT). Fifteen intensity-modulated radiation therapy (IMRT) plans of cervical cancer were chosen, and the plans were transferred to the pCT and cCBCT data sets without any changes for dose calculations. Phantom and patient studies were carried out. The dose differences and dose distributions were compared between cCBCT plan and pCT plan. Results: The HU number of CBCT was measured by several times, and the maximum change was less than 2%. To compare with pCT, the CBCT and cCBCT has a discrepancy, the dose differences in CBCT and cCBCT images were 2.48%±0.65% (range: 1.3%∼3.8%) and 0.48%±0.21% (range: 0.1%∼0.82%) for phantom study, respectively. For dose calculation in patient images, the dose differences were 2.25%±0.43% (range: 1.4%∼3.4%) and 0.63%±0.35% (range: 0.13%∼0.97%), respectively. And for the dose distributions, the passing rate of cCBCT was higher than the CBCTs. Conclusion: The CBCT image for dose calculation is feasible in cervical cancer radiotherapy, and the correction algorithm offers acceptable accuracy. It will become a useful tool for adaptive radiation therapy.

  9. Code System to Calculate Neutron and Gamma-Ray Skyshine Doses Using the Integral Line-Beam Method.

    Energy Science and Technology Software Center (OSTI)

    2000-11-16

    Version 03 This package includes the SKYNEUT 1.1, SKYDOSE 2.3, MCSKY 2.3 and SKYCONES 1.1 codes plus the DLC-188/SKYDATA library to form a comprehensive system for calculating skyshine doses. See the author's web site for related information: http://athena.mne.ksu.edu/~jks/ SKYNEUT evaluates the neutron and neutron-induced secondary gamma-ray skyshine doses from an isotropic, point, neutron source collimated by three simple geometries: an open silo, a vertical black (perfectly absorbing) wall, and a rectangular building. The source maymore » emit monoenergetic neutrons or neutrons with an arbitrary multigroup spectrum of energies. SKYDOSE evaluates the gamma-ray skyshine dose from an isotropic, monoenergetic, point gamma-photon source collimated by three simple geometries: (1) a source in a silo, (2) a source behind an infinitely long, vertical, black wall, and (3) a source in a rectangular building. In all three geometries an optional overhead slab shield may be specified. MCSKY evaluates the gamma-ray skyshine dose from an isotropic, monoenergetic, point gamma-photon source collimated into either a vertical cone (i.e., silo geometry) or into a vertically oriented structure with an N-sided polygon cross section. An overhead laminate shield composed of two different materials is assumed, although shield thicknesses of zero may be specified to model an unshielded SKYSHINE source. SKYCONES evaluates the skyshine doses produced by a point neutron or gamma-photon source emitting, into the atmosphere, radiation that is collimated into an upward conical annulus between two arbitrary polar angles. The source is assumed to be axially (azimuthally) symmetric about a vertical axis through the source and can have an arbitrary polyenergetic spectrum. Nested contiguous annular cones can thus be used to represent the energy and polar-angle dependence of a skyshine source emitting radiation into the atmosphere.« less

  10. Beam Status

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

    Beam Status Beam Status Print Loading... You can also view the Operations Group's Beam History archives.

  11. TURTLE with MAD input (Trace Unlimited Rays Through Lumped Elements) -- A computer program for simulating charged particle beam transport systems and DECAY TURTLE including decay calculations

    SciTech Connect (OSTI)

    Carey, D.C.

    1999-12-09

    TURTLE is a computer program useful for determining many characteristics of a particle beam once an initial design has been achieved, Charged particle beams are usually designed by adjusting various beam line parameters to obtain desired values of certain elements of a transfer or beam matrix. Such beam line parameters may describe certain magnetic fields and their gradients, lengths and shapes of magnets, spacings between magnetic elements, or the initial beam accepted into the system. For such purposes one typically employs a matrix multiplication and fitting program such as TRANSPORT. TURTLE is designed to be used after TRANSPORT. For convenience of the user, the input formats of the two programs have been made compatible. The use of TURTLE should be restricted to beams with small phase space. The lumped element approximation, described below, precludes the inclusion of the effect of conventional local geometric aberrations (due to large phase space) or fourth and higher order. A reading of the discussion below will indicate clearly the exact uses and limitations of the approach taken in TURTLE.

  12. Beam geometry selection using sequential beam addition

    SciTech Connect (OSTI)

    Popple, Richard A. Brezovich, Ivan A.; Fiveash, John B.

    2014-05-15

    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

  13. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, John B.

    1996-01-01

    An improved magnetically-confined anode plasma pulsed ion beam source. Beam rotation effects and power efficiency are improved by a magnetic design which places the separatrix between the fast field flux structure and the slow field structure near the anode of the ion beam source, by a gas port design which localizes the gas delivery into the gap between the fast coil and the anode, by a pre-ionizer ringing circuit connected to the fast coil, and by a bias field means which optimally adjusts the plasma formation position in the ion beam source.

  14. Beam Status

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

    Beam Status Print Loading... You can also view the Operations Group's Beam History archives

  15. Beam/seam alignment control for electron beam welding

    DOE Patents [OSTI]

    Burkhardt, Jr., James H.; Henry, J. James; Davenport, Clyde M.

    1980-01-01

    This invention relates to a dynamic beam/seam alignment control system for electron beam welds utilizing video apparatus. The system includes automatic control of workpiece illumination, near infrared illumination of the workpiece to limit the range of illumination and camera sensitivity adjustment, curve fitting of seam position data to obtain an accurate measure of beam/seam alignment, and automatic beam detection and calculation of the threshold beam level from the peak beam level of the preceding video line to locate the beam or seam edges.

  16. Beam current sensor

    DOE Patents [OSTI]

    Kuchnir, M.; Mills, F.E.

    1984-09-28

    A current sensor for measuring the dc component of a beam of charged particles employs a superconducting pick-up loop probe, with twisted superconducting leads in combination with a Superconducting Quantum Interference Device (SQUID) detector. The pick-up probe is in the form of a single-turn loop, or a cylindrical toroid, through which the beam is directed and within which a first magnetic flux is excluded by the Meisner effect. The SQUID detector acts as a flux-to-voltage converter in providing a current to the pick-up loop so as to establish a second magnetic flux within the electrode which nulls out the first magnetic flux. A feedback voltage within the SQUID detector represents the beam current of the particles which transit the pick-up loop. Meisner effect currents prevent changes in the magnetic field within the toroidal pick-up loop and produce a current signal independent of the beam's cross-section and its position within the toroid, while the combination of superconducting elements provides current measurement sensitivities in the nano-ampere range.

  17. Beam current sensor

    DOE Patents [OSTI]

    Kuchnir, Moyses; Mills, Frederick E.

    1987-01-01

    A current sensor for measuring the DC component of a beam of charged particles employs a superconducting pick-up loop probe, with twisted superconducting leads in combination with a Superconducting Quantum Interference Device (SQUID) detector. The pick-up probe is in the form of a single-turn loop, or a cylindrical toroid, through which the beam is directed and within which a first magnetic flux is excluded by the Meisner effect. The SQUID detector acts as a flux-to-voltage converter in providing a current to the pick-up loop so as to establish a second magnetic flux within the electrode which nulls out the first magnetic flux. A feedback voltage within the SQUID detector represents the beam current of the particles which transit the pick-up loop. Meisner effect currents prevent changes in the magnetic field within the toroidal pick-up loop and produce a current signal independent of the beam's cross-section and its position within the toroid, while the combination of superconducting elements provides current measurement sensitivites in the nano-ampere range.

  18. Beam-beam simulations for separated beams

    SciTech Connect (OSTI)

    Furman, Miguel A.

    2000-04-10

    We present beam-beam simulation results from a strong-strong gaussian code for separated beams for the LHC and RHIC. The frequency spectrum produced by the beam-beam collisions is readily obtained and offers a good opportunity for experimental comparisons. Although our results for the emittance blowup are preliminary, we conclude that, for nominal parameter values, there is no significant difference between separated beams and center-on-center collisions.

  19. Computational study of ion beam extraction phenomena through multiple apertures

    SciTech Connect (OSTI)

    Hu, Wanpeng; Sang, Chaofeng; Tang, Tengfei; Wang, Dezhen, E-mail: wangdez@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Li, Ming; Jin, Dazhi; Tan, Xiaohua [Institute of Electronic Engineering, Mianyang, 621900 (China)] [Institute of Electronic Engineering, Mianyang, 621900 (China)

    2014-03-15

    The process of ion extraction through multiple apertures is investigated using a two-dimensional particle-in-cell code. We consider apertures with a fixed diameter with a hydrogen plasma background, and the trajectories of electrons, H{sup +} and H{sub 2}{sup +} ions in the self-consistently calculated electric field are traced. The focus of this work is the fundamental physics of the ion extraction, and not particular to a specific device. The computed convergence and divergence of the extracted ion beam are analyzed. We find that the extracted ion flux reaching the extraction electrode is non-uniform, and the peak flux positions change according to operational parameters, and do not necessarily match the positions of the apertures in the y-direction. The profile of the ion flux reaching the electrode is mainly affected by the bias voltage and the distance between grid wall and extraction electrode.

  20. SU-E-J-100: The Combination of Deformable Image Registration and Regions-Of-Interest Mapping Technique to Accomplish Accurate Dose Calculation On Cone Beam Computed Tomography for Esophageal Cancer

    SciTech Connect (OSTI)

    Huang, B-T; Lu, J-Y

    2015-06-15

    Purpose: We introduce a new method combined with the deformable image registration (DIR) and regions-of-interest mapping (ROIM) technique to accurately calculate dose on daily CBCT for esophageal cancer. Methods: Patients suffered from esophageal cancer were enrolled in the study. Prescription was set to 66 Gy/30 F and 54 Gy/30 F to the primary tumor (PTV66) and subclinical disease (PTV54) . Planning CT (pCT) were segmented into 8 substructures in terms of their differences in physical density, such as gross target volume (GTV), venae cava superior (SVC), aorta, heart, spinal cord, lung, muscle and bones. The pCT and its substructures were transferred to the MIM software to readout their mean HU values. Afterwards, a deformable planning CT to daily KV-CBCT image registration method was then utilized to acquire a new structure set on CBCT. The newly generated structures on CBCT were then transferred back to the treatment planning system (TPS) and its HU information were overridden manually with mean HU values obtained from pCT. Finally, the treatment plan was projected onto the CBCT images with the same beam arrangements and monitor units (MUs) to accomplish dose calculation. Planning target volume (PTV) and organs at risk (OARs) from both of the pCT and CBCT were compared to evaluate the dose calculation accuracy. Results: It was found that the dose distribution in the CBCT showed little differences compared to the pCT, regardless of whether PTV or OARs were concerned. Specifically, dose variation in GTV, PTV54, PTV66, SVC, lung and heart were within 0.1%. The maximum dose variation was presented in the spinal cord, which was up to 2.7% dose difference. Conclusion: The proposed method combined with DIR and ROIM technique to accurately calculate dose distribution on CBCT for esophageal cancer is feasible.

  1. Co: clqrt. Beam

    Office of Legacy Management (LM)

    Co: clqrt. Beam*/:

  2. Muon fluxes and showers from dark matter annihilation in the...

    Office of Scientific and Technical Information (OSTI)

    We consider both the upward muon flux, when muons are created in the rock below the detector, and the contained flux when muons are created in the (ice) detector. We also calculate ...

  3. Fast flux locked loop

    DOE Patents [OSTI]

    Ganther, Jr., Kenneth R.; Snapp, Lowell D.

    2002-09-10

    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.

  4. 43 PARTICLE ACCELERATORS; ELECTRON GUNS; BEAM EMITTANCE; CHARGE

    Office of Scientific and Technical Information (OSTI)

    SPACE 430200* -- Particle Accelerators-- Beam Dynamics, Field Calculations, & Ion Optics The evolution of the electron-beam phase space distribution in laser-driven rf guns is...

  5. Using E-beam Mapping to Detect Coil Misalignment in NCSX

    SciTech Connect (OSTI)

    Fredrickson, E.; Georgiyevskiy, A.; Rudakov, V.; Zarnstorff, M. C.

    2005-10-18

    Following assembly of the NCSX device, a program of e-beam mapping experiments is planned to validate the accuracy of the construction and assembly of the NCSX coil systems. To aid in the development of requirements for the e-beam mapping hardware and machine requirements, simulations of the e-beam mapping experiments, including various coil misalignments, have been done. The magnetic flux surface configuration was constructed using a numerical code, based on the Biot-Savart law, to calculate the magnetic field components and trace the field line trajectory many times around the torus. Magnetic surfaces are then mapped by recording the field line intersections with toroidal cross-sections of the magnetic system, much as in an actual e-beam mapping experiment.

  6. Pulse flux measuring device

    DOE Patents [OSTI]

    Riggan, William C.

    1985-01-01

    A device for measuring particle flux comprises first and second photodiode detectors for receiving flux from a source and first and second outputs for producing first and second signals representing the flux incident to the detectors. The device is capable of reducing the first output signal by a portion of the second output signal, thereby enhancing the accuracy of the device. Devices in accordance with the invention may measure distinct components of flux from a single source or fluxes from several sources.

  7. Ion Beam Simulator

    Energy Science and Technology Software Center (OSTI)

    2005-11-08

    IBSimu(Ion Beam Simulator) is a computer program for making two and three dimensional ion optical simulations. The program can solve electrostatic field in a rectangular mesh using Poisson equation using Finite Difference method (FDM). The mesh can consist of a coarse and a fine part so that the calculation accuracy can be increased in critical areas of the geometry, while most of the calculation is done quickly using the coarse mesh. IBSimu can launch ionmore » beam trajectories into the simulation from an injection surface or fomo plasma. Ion beam space charge of time independent simulations can be taken in account using Viasov iteration. Plasma is calculated by compensating space charge with electrons having Boltzmann energy distribution. The simulation software can also be used to calculate time dependent cases if the space charge is not calculated. Software includes diagnostic tools for plotting the geometry, electric field, space charge map, ion beam trajectories, emittance data and beam profiles.« less

  8. NuMI Low Energy Flux Prediction Release

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

    NuMI Low Energy Flux Prediction Release Neutrino Flux Predictions for the NuMI Beam hep-ex/1607.00704 Data Ancillary data files for this result are available on arXiv at http://arxiv.org/src/1607.00704/anc.< /li> Among the available data files are: pdf file describing format of all the available files root file of all the available fluxes python code to read and process MINERvA's flux predictions Text Files of the flux, uncertainties, and covariance matrix, with units of neutrinos/m^2/POT,

  9. Photon beam position monitor

    DOE Patents [OSTI]

    Kuzay, T.M.; Shu, D.

    1995-02-07

    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.

  10. Photon beam position monitor

    DOE Patents [OSTI]

    Kuzay, Tuncer M.; Shu, Deming

    1995-01-01

    A photon beam position monitor 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.

  11. Beam Transport

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

    Beam Transport A simplified drawing of the beam transport system from the linac to Target-1 (Lujan Center), Target-2 (Blue Room) and Target-4 is shown below. In usual operation ...

  12. 6-D weak-strong beam-beam simulation study of proton lifetime in presence of head-on beam-beam compensation in the RHIC

    SciTech Connect (OSTI)

    Luo, Y.; Fischer, W.

    2010-08-01

    In this note we summarize the calculated particle loss of a proton bunch in the presence of head-on beam-beam compensation in the Relativistic Heavy Ion Collider (RHIC). To compensate the head-on beam-beam effect in the RHIC 250 GeV polarized proton run, we are introducing a DC electron beam with the same transverse profile as the proton beam to collide with the proton beam. Such a device is called an electron lens (e-lens). In this note we first present the optics and beam parameters and the tracking setup. Then we calculate and compare the particle loss of a proton bunch with head-on beam-beam compensation, phase advance of k{pi} between IP8 and the center of the e-lens and second order chromaticity correction. We scanned the proton beam's linear chromaticity, working point and bunch intensity. We also scanned the electron beam's intensity, transverse beam size. The effect of the electron-proton transverse offset in the e-lens was studied. In the study 6-D weak-strong beam-beam interaction model a la Hirata is used for proton collisions at IP6 and IP8. The e-lens is modeled as 8 slices. Each slice is modeled with as drift - (4D beam-beam kick) - drift.

  13. SRU Calculator

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

    Calculator SRU Calculator About SRUs You can use this form to estimate your mass storage charges (in SRUs). SRUs are calculated on a daily basis. Enter your estimated daily average number of files and data storage and your yearly estimate of data transferred to and from the HPSS system. Click on Calculate and your SRU charge will appear in the light blue boxes. Enter average daily values for the allocation year Number of files*: Amount of data stored*: GB Enter total HPSS I/O for the allocation

  14. Beam characterization by wavefront sensor

    DOE Patents [OSTI]

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

    1999-08-10

    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. Beam characterization by wavefront sensor

    DOE Patents [OSTI]

    Neal, Daniel R.; Alford, W. J.; Gruetzner, James K.

    1999-01-01

    An apparatus and method 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.

  16. Heat flux viscosity in collisional magnetized plasmas

    SciTech Connect (OSTI)

    Liu, C.; Fox, W.; Bhattacharjee, A.

    2015-05-15

    Momentum transport in collisional magnetized plasmas due to gradients in the heat flux, a “heat flux viscosity,” is demonstrated. Even though no net particle flux is associated with a heat flux, in a plasma there can still be momentum transport owing to the velocity dependence of the Coulomb collision frequency, analogous to the thermal force. This heat-flux viscosity may play an important role in numerous plasma environments, in particular, in strongly driven high-energy-density plasma, where strong heat flux can dominate over ordinary plasma flows. The heat flux viscosity can influence the dynamics of the magnetic field in plasmas through the generalized Ohm's law and may therefore play an important role as a dissipation mechanism allowing magnetic field line reconnection. The heat flux viscosity is calculated directly using the finite-difference method of Epperlein and Haines [Phys. Fluids 29, 1029 (1986)], which is shown to be more accurate than Braginskii's method [S. I. Braginskii, Rev. Plasma Phys. 1, 205 (1965)], and confirmed with one-dimensional collisional particle-in-cell simulations. The resulting transport coefficients are tabulated for ease of application.

  17. ARM - Measurement - Methane flux

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

    flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Methane flux Vertical flux of methane near the surface due to turbulent transport. Categories Surface Properties, Atmospheric Carbon Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including

  18. BEAM PROPAGATOR

    Energy Science and Technology Software Center (OSTI)

    003691MLTPL00 Beam Propagator for Weather Radars, Modules 1 and 2 http://www.exelisvis.com/ProductsServices/IDL.aspx

  19. Beam History

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

    Beam Status Beam History Print Beamline History Request Form To request a beam current histograph from the ALS storage ring beam histograph database, select the year, month, and day, then click on "Submit Request". Histographs are available as far back as February 2, 1994. Year 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day 01 02 03 04 05 06 07 08 09 10 11 12 13

  20. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, J.B.

    1997-08-12

    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.

  1. HIGS Flux Performance Projection

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

    HIGS flux performance table for high-flux, quasi-CW operation, DFELL/TUNL, Nov. 9, 2010 (Version 2.3). HIGS Flux Performance Projection (2010 - 2011) Total Flux [g/s] CW Operation Two-Bunch (*) Collimated Flux (∆E γ /E γ = 5% FWHM) (#), (@) FEL λ [nm] Comment No-loss Mode : < 20 MeV Linear Pol. with OK-4 Circular Pol with OK-5 E γ = 1 - 2 MeV (E e = 237 - 336 MeV) 1 x 10 8 - 4 x 10 8 6 x 10 6 - 2.4 x 10 7 1064 Linear and Circular (a), (b) E γ = 2 - 2.9 MeV (E e = 336 - 405 MeV) 4 x 10

  2. PHELIX for flux compression studies

    SciTech Connect (OSTI)

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

    2010-06-28

    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.

  3. Measurement of neutrino flux from neutrino-electron elastic scattering

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

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; et al

    2016-06-10

    In muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ~10% due to uncertainties in hadron production and focusing. We also isolated a sample of 135±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux frommore » 9% to 6%. Finally, our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.« less

  4. Neutral beam dump with cathodic arc titanium gettering

    SciTech Connect (OSTI)

    Smirnov, A.; Korepanov, S. A.; Putvinski, S.; Krivenko, A. S.; Murakhtin, S. V.; Savkin, V. Ya.

    2011-03-15

    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.

  5. Remarks on calculation of positron flux from galactic dark matter...

    Office of Scientific and Technical Information (OSTI)

    ANTIPARTICLES; BASIC INTERACTIONS; BOSONS; ELASTIC SCATTERING; ELECTROMAGNETIC INTERACTIONS; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; FERMIONS; GALAXIES; INTERACTIONS; ...

  6. Development of Aerosol Models for Radiative Flux Calculations...

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

    Plains (SGP), and North Slope of Alaska (NSA) sites to begin development of a set of ... Aerosol properties at the SGP and NSA sites show considerable variability on multiple time ...

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

    DOE Patents [OSTI]

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

    1990-01-01

    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.

  8. Beam tuning

    SciTech Connect (OSTI)

    Pardo, R.C.; Zinkann, G.P.

    1995-08-01

    A program for configuring the linac, based on previously run configurations for any desired beam was used during the past year. This program uses only a small number of empirical tunes to scale resonator fields to properly accelerate a beam with a different charge-to-mass (q/A) ratio from the original tune configuration. The program worked very well for the PII linac section where we can easily match a new beam`s arrival phase and velocity to the tuned value. It was also fairly successful for the Booster and ATLAS sections of the linac, but not as successful as for the PII linac. Most of the problems are associated with setting the beam arrival time correctly for each major linac section. This problem is being addressed with the development of the capacitive pickup beam phase monitor discussed above. During the next year we expect to improve our ability to quickly configure the linac for new beams and reduce the time required for linac tuning. Already the time required for linac tuning as a percentage of research hours has decreased from 22% in FY 1993 to 15% in the first quarter of FY 1995.

  9. Beam History

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

    Beam History Print Beamline History Request Form To request a beam current histograph from the ALS storage ring beam histograph database, select the year, month, and day, then click on "Submit Request". Histographs are available as far back as February 2, 1994. Year 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17

  10. Beam History

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

    Beam History Print Beamline History Request Form To request a beam current histograph from the ALS storage ring beam histograph database, select the year, month, and day, then click on "Submit Request". Histographs are available as far back as February 2, 1994. Year 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17

  11. ARM - Measurement - Actinic flux

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

    would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Actinic flux The quantity of light in the atmosphere available to molecules at a...

  12. WBGT Calculator

    Energy Science and Technology Software Center (OSTI)

    2000-05-22

    This software calculates a Wet Bulb Globe Temperature (WBGT) using standard measurements from a meteorological station. WBGT is used by Industrial Hygenists (IH) to determine heat stress potential to outdoor workers. Through the mid 1990''s, SRS technicians were dispatched several times daily to measure WBGT with a custom hand held instrument and results were dessiminated via telephone. Due to workforce reductions, the WSRC IH Department asked for the development of an automated method to simulatemore » the WBGT measurement using existing real time data from the Atmospheric Technologies Group''s meteorological monitoring network.« less

  13. Beam Test Facility

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

    Beam Test Facility Beam Test Facility Print Tuesday, 20 October 2009 09:36 Coming Soon

  14. Measurements - Ion Beams - Radiation Effects Facility / Cyclotron Institute

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

    / Texas A&M University Ion Beams Available Beams / Beam Change Times / Measurements / Useful Graphs Measurements The beam uniformity and flux are determined using an array of five detectors. Each detector is made up with a plastic scintillator coupled to photo-multiplier tubes. Four of the detectors are fixed in position and set up to measure beam particle counting rates continuously at four characteristic points 1.64 inches (4.71 mm) away from the beam axis. The fifth scintillator can

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

    SciTech Connect (OSTI)

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

    2008-05-01

    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.

  16. Muon fluxes from dark matter annihilation (Journal Article) ...

    Office of Scientific and Technical Information (OSTI)

    We calculate the muon flux from annihilation of the dark matter in the core of the Sun, in the ... We illustrate how muon energy distribution from dark matter annihilation ...

  17. Quantum flux parametron

    SciTech Connect (OSTI)

    Hioe, W. ); Goto, E. )

    1991-01-01

    The quantum flux parametron (QFP) is an offspring of the parametron, an early flux-based logic device, and the Josephson junction. It is a single flux quantum device that works completely in the superconductive mode. While it has the speed of other Josephson devices that work on switching between the voltage and superconductive modes, its power is about one thousand times less. Hence, it promises to be an attractive alternative to both transistors and other Josephson devices. This book reports the latest research results on QFP applications as a logic device. In particular, a number of auxiliary circuits and a new logic gate are proposed for improving the device margin. Samples of these circuits and logic gate have been fabricated.

  18. Simulation study of dynamic aperture with head-on beam-beam compensation in the RHIC

    SciTech Connect (OSTI)

    Luo, Y.; Fischer, W.

    2010-08-01

    In this note we summarize the calculated 10{sup 6} turn dynamic apertures with the proposed head-on beam-beam compensation in the Relativistic Heavy Ion Collider (RHIC). To compensate the head-on beam-beam effect in the RHIC 250 GeV polarized proton run, we are planning to introduce a DC electron beam with the same transverse profile as the proton beam to collide with the proton beam. Such a device to provide the electron beam is called an electron lens (e-lens). In this note we first present the optics and beam parameters and the tracking setup. Then we compare the calculated dynamic apertures without and with head-on beam-beam compensation. The effects of adjusted phase advances between IP8 and the center of e-lens and second order chromaticity correction are checked. In the end we will scan the proton and electron beam parameters with head-on beam-beam compensation.

  19. A new luminescence beam profile monitor for intense proton and heavy ion beams

    SciTech Connect (OSTI)

    Tsang,T.; Bellavia, S.; Connolly, R.; Gassner, D.; Makdisi, Y.; Russo, T.; Thieberger, P.; Trbojevic, D.; Zelenski, A.

    2008-10-01

    A new luminescence beam profile monitor is realized in the polarized hydrogen gas jet target at the Relativistic Heavy Ion Collider (RHIC) facility. In addition to the spin polarization of the proton beam being routinely measured by the hydrogen gas jet, the luminescence produced by beam-hydrogen excitation leads to a strong Balmer series lines emission. A selected hydrogen Balmer line is spectrally filtered and imaged to produce the transverse RHIC proton beam shape with unprecedented details on the RHIC beam profile. Alternatively, when the passage of the high energy RHIC gold ion beam excited only the residual gas molecules in the beam path, sufficient ion beam induced luminescence is produced and the transverse gold ion beam profile is obtained. The measured transverse beam sizes and the calculated emittances provide an independent confirmation of the RHIC beam characteristics and to verify the emittance conservation along the RHIC accelerator. This optical beam diagnostic technique by making use of the beam induced fluorescence from injected or residual gas offers a truly noninvasive particle beam characterization, and provides a visual observation of proton and heavy ion beams. Combined with a longitudinal bunch measurement system, a 3-dimensional spatial particle beam profile can be reconstructed tomographically.

  20. Radiative Flux Analysis

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

    Long, Chuck [NOAA

    2008-05-14

    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.

  1. Asymptotic, multigroup flux reconstruction and consistent discontinuity factors

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

    Trahan, Travis J.; Larsen, Edward W.

    2015-05-12

    Recent theoretical work has led to an asymptotically derived expression for reconstructing the neutron flux from lattice functions and multigroup diffusion solutions. The leading-order asymptotic term is the standard expression for flux reconstruction, i.e., it is the product of a shape function, obtained through a lattice calculation, and the multigroup diffusion solution. The first-order asymptotic correction term is significant only where the gradient of the diffusion solution is not small. Inclusion of this first-order correction term can significantly improve the accuracy of the reconstructed flux. One may define discontinuity factors (DFs) to make certain angular moments of the reconstructed fluxmore » continuous across interfaces between assemblies in 1-D. Indeed, the standard assembly discontinuity factors make the zeroth moment (scalar flux) of the reconstructed flux continuous. The inclusion of the correction term in the flux reconstruction provides an additional degree of freedom that can be used to make two angular moments of the reconstructed flux continuous across interfaces by using current DFs in addition to flux DFs. Thus, numerical results demonstrate that using flux and current DFs together can be more accurate than using only flux DFs, and that making the second angular moment continuous can be more accurate than making the zeroth moment continuous.« less

  2. Atmospheric State, Cloud Microphysics and Radiative Flux

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

    Mace, Gerald

    2008-01-15

    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.

  3. 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.

  4. Beam current controller for laser ion source

    DOE Patents [OSTI]

    Okamura, Masahiro

    2014-10-28

    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.

  5. 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.

    1991-04-09

    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.

  6. High sensitivity charge amplifier for ion beam uniformity monitor

    DOE Patents [OSTI]

    Johnson, Gary W.

    2001-01-01

    An ion beam uniformity monitor for very low beam currents using a high-sensitivity charge amplifier with bias compensation. The ion beam monitor is used to assess the uniformity of a raster-scanned ion beam, such as used in an ion implanter, and utilizes four Faraday cups placed in the geometric corners of the target area. Current from each cup is integrated with respect to time, thus measuring accumulated dose, or charge, in Coulombs. By comparing the dose at each corner, a qualitative assessment of ion beam uniformity is made possible. With knowledge of the relative area of the Faraday cups, the ion flux and areal dose can also be obtained.

  7. NEUTRON FLUX INTENSITY DETECTION

    DOE Patents [OSTI]

    Russell, J.T.

    1964-04-21

    A method of measuring the instantaneous intensity of neutron flux in the core of a nuclear reactor is described. A target gas capable of being transmuted by neutron bombardment to a product having a resonance absorption line nt a particular microwave frequency is passed through the core of the reactor. Frequency-modulated microwave energy is passed through the target gas and the attenuation of the energy due to the formation of the transmuted product is measured. (AEC)

  8. 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

    2013-07-01

    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.

  9. ARM - Measurement - Sensible heat flux

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

    heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Sensible heat flux The time ...

  10. ARM - Measurement - Latent heat flux

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

    heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Latent heat flux The time ...

  11. CEBAF beam loss accounting

    SciTech Connect (OSTI)

    Ursic, R.; Mahoney, K.; Hovater, C.; Hutton, A.; Sinclair, C.

    1995-12-31

    This paper describes the design and implementation of a beam loss accounting system for the CEBAF electron accelerator. This system samples the beam curent throughout the beam path and measures the beam current accurately. Personnel Safety and Machine Protection systems use this system to turn off the beam when hazardous beam losses occur.

  12. Method for finding the beam waist through ABCD matrix element adjustment

    SciTech Connect (OSTI)

    Evans, J.D.

    1988-12-15

    Laser beam parameters includingbeam waist are calculated for laser cavities using an equivalent lens waveguide approach.(AIP)

  13. The distribution of ion orbit loss fluxes of ions and energy from the plasma edge across the last closed flux surface into the scrape-off layer

    SciTech Connect (OSTI)

    Stacey, Weston M.; Schumann, Matthew T.

    2015-04-15

    A more detailed calculation strategy for the evaluation of ion orbit loss of thermalized plasma ions in the edge of tokamaks is presented. In both this and previous papers, the direct loss of particles from internal flux surfaces is calculated from the conservation of canonical angular momentum, energy, and magnetic moment. The previous result that almost all of the ion energy and particle fluxes crossing the last closed flux surface are in the form of ion orbit fluxes is confirmed, and the new result that the distributions of these fluxes crossing the last closed flux surface into the scrape-off layer are very strongly peaked about the outboard midplane is demonstrated. Previous results of a preferential loss of counter current particles leading to a co-current intrinsic rotation peaking just inside of the last closed flux surface are confirmed. Various physical details are discussed.

  14. Canister Transfer Facility Criticality Calculations

    SciTech Connect (OSTI)

    J.E. Monroe-Rammsy

    2000-10-13

    The objective of this calculation is to evaluate the criticality risk in the surface facility for design basis events (DBE) involving Department of Energy (DOE) Spent Nuclear Fuel (SNF) standardized canisters (Civilian Radioactive Waste Management System [CRWMS] Management and Operating Contractor [M&O] 2000a). Since some of the canisters will be stored in the surface facility before they are loaded in the waste package (WP), this calculation supports the demonstration of concept viability related to the Surface Facility environment. The scope of this calculation is limited to the consideration of three DOE SNF fuels, specifically Enrico Fermi SNF, Training Research Isotope General Atomic (TRIGA) SNF, and Mixed Oxide (MOX) Fast Flux Test Facility (FFTF) SNF.

  15. Confined ion beam sputtering device and method

    DOE Patents [OSTI]

    Sharp, D.J.

    1986-03-25

    A hollow cylindrical target, lined internally with a sputter deposit material and open at both ends, surrounds a substrate on which sputtered deposition is to be obtained. An ion beam received through either one or both ends of the open cylindrical target is forced by a negative bias applied to the target to diverge so that ions impinge at acute angles at different points of the cylindrical target surface. The ion impingement results in a radially inward and downstream directed flux of sputter deposit particles that are received by the substrate. A positive bias applied to the substrate enhances divergence of the approaching ion beams to generate a higher sputtered deposition flux rate. Alternatively, a negative bias applied to the substrate induces the core portion of the ion beams to reach the substrate and provide ion polishing of the sputtered deposit thereon.

  16. Confined ion beam sputtering device and method

    DOE Patents [OSTI]

    Sharp, Donald J.

    1988-01-01

    A hollow cylindrical target, lined internally with a sputter deposit material and open at both ends, surrounds a substrate on which sputtered deposition is to be obtained. An ion beam received through either one or both ends of the open cylindrical target is forced by a negative bias applied to the target to diverge so that ions impinge at acute angles at different points of the cylindrical target surface. The ion impingement results in a radially inward and downstream directed flux of sputter deposit particles that are received by the substrate. A positive bias applied to the substrate enhances divergence of the approaching ion beams to generate a higher sputtered deposition flux rate. Alternatively, a negative bias applied to the substrate induces the core portion of the ion beams to reach the substrate and provide ion polishing of the sputtered deposit thereon.

  17. Portable radiography system using a relativistic electron beam

    DOE Patents [OSTI]

    Hoeberling, R.F.

    1987-09-22

    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.

  18. Portable radiography system using a relativistic electron beam

    DOE Patents [OSTI]

    Hoeberling, Robert F.

    1990-01-01

    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.

  19. High flux, narrow bandwidth compton light sources via extended laser-electron interactions

    DOE Patents [OSTI]

    Barty, V P

    2015-01-13

    New configurations of lasers and electron beams efficiently and robustly produce high flux beams of bright, tunable, polarized quasi-monoenergetic x-rays and gamma-rays via laser-Compton scattering. Specifically, the use of long-duration, pulsed lasers and closely-spaced, low-charge and low emittance bunches of electron beams increase the spectral flux of the Compton-scattered x-rays and gamma rays, increase efficiency of the laser-electron interaction and significantly reduce the overall complexity of Compton based light sources.

  20. Influence of polarization and a source model for dose calculation in MRT

    SciTech Connect (OSTI)

    Bartzsch, Stefan Oelfke, Uwe; Lerch, Michael; Petasecca, Marco; Bruer-Krisch, Elke

    2014-04-15

    Purpose: Microbeam Radiation Therapy (MRT), an alternative preclinical treatment strategy using spatially modulated synchrotron radiation on a micrometer scale, has the great potential to cure malignant tumors (e.g., brain tumors) while having low side effects on normal tissue. Dose measurement and calculation in MRT is challenging because of the spatial accuracy required and the arising high dose differences. Dose calculation with Monte Carlo simulations is time consuming and their accuracy is still a matter of debate. In particular, the influence of photon polarization has been discussed in the literature. Moreover, it is controversial whether a complete knowledge of phase space trajectories, i.e., the simulation of the machine from the wiggler to the collimator, is necessary in order to accurately calculate the dose. Methods: With Monte Carlo simulations in the Geant4 toolkit, the authors investigate the influence of polarization on the dose distribution and the therapeutically important peak to valley dose ratios (PVDRs). Furthermore, the authors analyze in detail phase space information provided byMartnez-Rovira et al. [Development and commissioning of a Monte Carlo photon model for the forthcoming clinical trials in microbeam radiation therapy, Med. Phys. 39(1), 119131 (2012)] and examine its influence on peak and valley doses. A simple source model is developed using parallel beams and its applicability is shown in a semiadjoint Monte Carlo simulation. Results are compared to measurements and previously published data. Results: Polarization has a significant influence on the scattered dose outside the microbeam field. In the radiation field, however, dose and PVDRs deduced from calculations without polarization and with polarization differ by less than 3%. The authors show that the key consequences from the phase space information for dose calculations are inhomogeneous primary photon flux, partial absorption due to inclined beam incidence outside the

  1. High flux reactor

    DOE Patents [OSTI]

    Lake, James A.; Heath, Russell L.; Liebenthal, John L.; DeBoisblanc, Deslonde R.; Leyse, Carl F.; Parsons, Kent; Ryskamp, John M.; Wadkins, Robert P.; Harker, Yale D.; Fillmore, Gary N.; Oh, Chang H.

    1988-01-01

    A high flux reactor is comprised of a core which is divided into two symetric segments housed in a pressure vessel. The core segments include at least one radial fuel plate. The spacing between the plates functions as a coolant flow channel. The core segments are spaced axially apart such that a coolant mixing plenum is formed between them. A channel is provided such that a portion of the coolant bypasses the first core section and goes directly into the mixing plenum. The outlet coolant from the first core segment is mixed with the bypass coolant resulting in a lower inlet temperature to the lower core segment.

  2. Specific features of measuring the isotopic composition of hydrogen ions in ITER plasma by using neutral particle diagnostics under neutral beam injection conditions

    SciTech Connect (OSTI)

    Afanasyev, V. I.; Goncharov, P. R.; Mironov, M. I.; Nesenevich, V. G. Petrov, M. P.; Petrov, S. Ya.; Sergeev, V. Yu.

    2015-12-15

    Results of numerical simulation of signals from neutral particle analyzers under injection of the heating and diagnostic neutral beams in different operating modes of the ITER tokamak are presented. The distribution functions of fast ions in plasma are simulated, and the corresponding neutral particle fluxes escaping from the plasma along the line of sight of the analyzers are calculated. It is shown that the injection of heating deuterium (D{sup 0}) beams results in the appearance of an intense background signal hampering measurements of the ratio between the densities of deuterium and tritium fuel ions in plasma in the thermal energy range. The injection of a diagnostic hydrogen (H{sup 0}) beam does not affect measurements owing to the high mass resolution of the analyzers.

  3. Neutrino Flux Prediction for the NuMI Beamline

    SciTech Connect (OSTI)

    Aliaga Soplin, Leonidas

    2016-01-01

    The determination of the neutrino flux in any conventional neutrino beam presents a challenge for the current and future short and long baseline neutrino experiments. The uncertainties associated with the production and attenuation of the hadrons in the beamline materials along with those associated with the beam optics have a big effect in the flux spectrum knowledge. For experiments like MINERvA, understanding the flux is crucial since it enters directly into every neutrino-nucleus cross-sections measurements. The foundation of this work is predicting the neutrino flux at MINERvA using dedicated measurements of hadron production in hadron-nucleus collisions and incorporating in-situ MINERvA data that can provide additional constraints. This work also includes the prospect for predicting the flux at other detectors like the NOvA Near detector. The procedure and conclusions of this thesis will have a big impact on future hadron production experiments and on determining the fl ux for the upcoming DUNE experiment.

  4. Mode selectivity in multiple-beam klystrons

    SciTech Connect (OSTI)

    Nusinovich, Gregory S.; Abe, David K.

    2006-09-15

    A general method is developed for calculating the coupling coefficients of multiple beamlets of an arbitrary geometry to resonator fields having an arbitrary transverse distribution. A number of examples illustrate the effectiveness of this method for calculating coupling coefficients and show the effect of device parameters on the coupling of a given multiple electron beam to competing modes of multiple-beam klystrons (MBKs) operating in high-order modes. The method can be used for evaluating the mode selectivity and the 'monotron instability' in MBKs. It can also be used for determining the Pierce gain parameter in multiple-beam traveling-wave tubes.

  5. Natural convection burnout heat flux limit for control rods

    SciTech Connect (OSTI)

    Britt, T.E.

    1986-04-14

    Technical Standard 105-3.05, Safety Circuits, does not require the Septifoil Supply Header Pressure Very Low safety circuit for current charges. This document develops a new requirement for this circuit based on the burnout heat flux of a control rod under natural convective cooling. Specifically, the Septifoil Supply Header Pressure Very Low safety circuit will be required whenever the calculated control rod operating heat flux exceeds 155,000 pcu/ft{sup 2}-hr.

  6. Scattered hard X-ray and γ-ray generation from a chromatic electron beam

    SciTech Connect (OSTI)

    Coleman, J. E.; Welch, D. R.; Miller, C. L.

    2015-11-14

    An array of photon diagnostics has been deployed on a high power relativistic electron beam diode. Electrons are extracted through a 17.8 cm diode from the surface discharge of a carbon fiber velvet cathode with a nominal diode voltage of 3.8 MV. <10% of the 100 ns electron pulse is composed of off energy electrons (1–3 MeV) accelerated during the rise and fall of the pulse that impact the stainless steel beam pipe and generate a Bremsstrahlung spectrum of 0.1–3 MeV photons with a total count of 10{sup 11}. The principal objective of these experiments is to quantify the electron beam dynamics and spatial dynamics of the hard X-ray and γ-ray flux generated in the diode region. A qualitative comparison of experimental and calculated results are presented, including time and energy resolved electron beam propagation and scattered photon measurements with X-ray PIN diodes and a photomultiplier tube indicating a dose dependence on the diode voltage >V{sup 4} and detected photon counts of nearly 10{sup 6} at a radial distance of 1 m which corresponds to dose ∼40 μrad at 1 m.

  7. Optics of ion beams for the neutral beam injection system on HL-2A Tokamak

    SciTech Connect (OSTI)

    Zou, G. Q.; Lei, G. J.; Cao, J. Y.; Duan, X. R.

    2012-07-15

    The ion beam optics for the neutral beam injection system on HL-2A Tokomak is studied by two- dimensional numerical simulation program firstly, where the emitting surface is taken at 100 Debye lengths from the plasma electrode. The mathematical formulation, computation techniques are described. Typical ion orbits, equipotential contours, and emittance diagram are shown. For a fixed geometry electrode, the effect of plasma density, plasma potential and plasma electron temperature on ion beam optics is examined, and the calculation reliability is confirmed by experimental results. In order to improve ion beam optics, the application of a small pre-acceleration voltage ({approx}100 V) between the plasma electrode and the arc discharge anode is reasonable, and a lower plasma electron temperature is desired. The results allow optimization of the ion beam optics in the neutral beam injection system on HL-2A Tokomak and provide guidelines for designing future neutral beam injection system on HL-2M Tokomak.

  8. Method of automatic measurement and focus of an electron beam and apparatus therefor

    DOE Patents [OSTI]

    Giedt, Warren H.; Campiotti, Richard

    1996-01-01

    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. 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.

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

    DOE Patents [OSTI]

    Giedt, W.H.; Campiotti, R.

    1996-01-09

    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.

  10. Laser beam monitoring system

    DOE Patents [OSTI]

    Weil, Bradley S.; Wetherington, Jr., Grady R.

    1985-01-01

    Laser beam monitoring systems include laser-transparent plates set at an angle to the laser beam passing therethrough and light sensor for detecting light reflected from an object on which the laser beam impinges.

  11. Laser beam monitoring system

    DOE Patents [OSTI]

    Weil, B.S.; Wetherington, G.R. Jr.

    Laser beam monitoring systems include laser-transparent plates set at an angle to the laser beam passing therethrough and light sensor for detecting light reflected from an object on which the laser beam impinges.

  12. Relativistic electron beam generator

    DOE Patents [OSTI]

    Mooney, L.J.; Hyatt, H.M.

    1975-11-11

    A relativistic electron beam generator for laser media excitation is described. The device employs a diode type relativistic electron beam source having a cathode shape which provides a rectangular output beam with uniform current density.

  13. BEAMS: Curiosity | Jefferson Lab

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

    BEAMS: Curiosity BEAMS: Curiosity January 9, 2013 BEAMS, Becoming Excited About Math and Science, is one of our education programs. In particular, it is the only one in which I ...

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

    SciTech Connect (OSTI)

    Campergue, A.-L.; Jacquet, P.; Monakhov, I.; Arnoux, G.; Brix, M.; Sirinelli, A.; Milanesio, D.; Colas, L.; Collaboration: JET-EFDA Contributors

    2014-02-12

    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. Beam imaging sensor

    DOE Patents [OSTI]

    McAninch, Michael D; Root, Jeffrey J

    2015-03-31

    The present invention relates generally to the field of sensors for beam imaging and, in particular, to a new and useful beam imaging sensor for use in determining, for example, the power density distribution of a beam including, but not limited to, an electron beam or an ion beam. In one embodiment, the beam imaging sensor of the present invention comprises, among other items, a circumferential slit that is either circular, elliptical or polygonal in nature.

  16. Beam imaging sensor

    DOE Patents [OSTI]

    McAninch, Michael D.; Root, Jeffrey J.

    2016-07-05

    The present invention relates generally to the field of sensors for beam imaging and, in particular, to a new and useful beam imaging sensor for use in determining, for example, the power density distribution of a beam including, but not limited to, an electron beam or an ion beam. In one embodiment, the beam imaging sensor of the present invention comprises, among other items, a circumferential slit that is either circular, elliptical or polygonal in nature.

  17. Interactive Beam-Dynamics Program

    Energy Science and Technology Software Center (OSTI)

    2001-01-08

    TRACE3D is an interactive program that calculates the envelopes of a bunched beam, including linear space-charge forces, through a user-defined system. The transport system may consist of the following elements: drift, thin lens, quadrupole, permanent magnet quadrupole, solenoid, doublet, triplet, bending magnet, edge angle (for bend), RF gap, radio-frequency-quadrupole cell, RF cavity, coupled-cavity tank, user-desired element, coordinate rotation, and identical element. The beam is represented by a 6X6 matrix defining a hyper-ellipsoid in six-dimensional phasemore » space. The projection of this hyperellipsoid on any two-dimensional plane is an ellipse that defines the boundary of the beam in that plane.« less

  18. BEAM INSTRUMENTATION FOR HIGH POWER HADRON BEAMS

    SciTech Connect (OSTI)

    Aleksandrov, Alexander V

    2013-01-01

    This presentation will describe developments in the beam diagnostics which support the understanding and operation of high power hadron accelerators. These include the measurement of large dynamic range transverse and longitudinal beam profiles, beam loss detection, and non-interceptive diagnostics.

  19. Development of the beam extraction synchronization system at the Fermilab Booster

    SciTech Connect (OSTI)

    Seiya, K.; Chaurize, S.; Drennan, C. C.; Pellico, W.; Sullivan, T.; Triplett, A. K.; Waller, A. M.

    2015-07-28

    The new beam extraction synchronization control system called “Magnetic Cogging” was developed at the Fermilab Booster and it replaces a system called “RF Cogging” as part of the Proton Improvement Plan (PIP). [1] The flux throughput goal for the PIP is 2.2×1017 protons per hour, which is double the present flux. Thus, the flux increase will be accomplished by doubling the number of beam cycles which, in turn, will double the beam loss in the Booster accelerator if nothing else is done.

  20. Development of the beam extraction synchronization system at the Fermilab Booster

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

    Seiya, K.; Chaurize, S.; Drennan, C. C.; Pellico, W.; Sullivan, T.; Triplett, A. K.; Waller, A. M.

    2015-07-28

    The new beam extraction synchronization control system called “Magnetic Cogging” was developed at the Fermilab Booster and it replaces a system called “RF Cogging” as part of the Proton Improvement Plan (PIP). [1] The flux throughput goal for the PIP is 2.2×1017 protons per hour, which is double the present flux. Thus, the flux increase will be accomplished by doubling the number of beam cycles which, in turn, will double the beam loss in the Booster accelerator if nothing else is done.

  1. Development of the beam extraction synchronization system at the Fermilab Booster

    SciTech Connect (OSTI)

    Seiya, K.; Chaurize, S.; Drennan, C. C.; Pellico, W.; Sullivan, T.; Triplett, A. K.; Waller, A. M.

    2015-07-28

    The new beam extraction synchronization control system called Magnetic Cogging was developed at the Fermilab Booster and it replaces a system called RF Cogging as part of the Proton Improvement Plan (PIP). [1] The flux throughput goal for the PIP is 2.21017 protons per hour, which is double the present flux. Thus, the flux increase will be accomplished by doubling the number of beam cycles which, in turn, will double the beam loss in the Booster accelerator if nothing else is done.

  2. The New Uppsala Neutron Beam Facility

    SciTech Connect (OSTI)

    Pomp, S.; Blomgren, J.; Hildebrand, A.; Johansson, C.; Mermod, P.; Oesterlund, M.; Prokofiev, A.V.; Bystroem, O.; Ekstroem, C.; Haag, N.; Jonsson, O.; Reistad, D.; Renberg, P.-U.; Wessman, D.; Ziemann, V.; Nilsson, L.; Olsson, N.; Tippawan, U.

    2005-05-24

    A new quasi-monoenergetic neutron beam facility has been constructed at the The Svedberg Laboratory (TSL) in Uppsala, Sweden. Key features include an energy range of 20 to 175 MeV, high fluxes, and the possibility of large-area fields. Besides cross-section measurements, the new facility has been designed specifically to provide optimal conditions for testing of single-event effects in electronics and for dosimetry development. First results of the beam characterization measurements performed in early 2004 are reported.

  3. Beam halo in mismatched proton beams.

    SciTech Connect (OSTI)

    Wangler, Thomas P.,; Allen, C. K.; Chan, D.; Colestock, P. L. ,; Crandall, K. R.; Qiang, J.; Garnett, R. W.; Lysenko, W. P.; Gilpatrick, J. D.; Schneider, J. D.; Schulze, M. E.; Sheffield, R. L.; Smith, H. V.

    2002-01-01

    Progress was made during the past decade towards a better understanding of halo formation caused by beam mismatch in high-intensity beams. To test these ideas an experiment was carried out at Los Alamos with proton beams in a 52-quadrupole focusing channel. Rms emittances and beam widths were obtained from measured beam profiles for comparison with the maximum emittance growth predictions of a free-energy model and the maximum haloamplitude predictions of a particle-core model. The experimental results are also compared with multiparticle simulations. In this paper we will present the experimental results and discuss the implications with respect to the validity of both the models and the simulations. Keywords: beam halo, emittance growth, beam profiles, simulations, space charge, mismatch

  4. PHLUX: Photographic Flux Tools for Solar Glare and Flux

    Energy Science and Technology Software Center (OSTI)

    2010-12-02

    A web-based tool to a) analytically and empirically quantify glare from reflected light and determine the potential impact (e.g., temporary flash blindness, retinal burn), and b) produce flux maps for central receivers. The tool accepts RAW digital photographs of the glare source (for hazard assessment) or the receiver (for flux mapping), as well as a photograph of the sun for intensity and size scaling. For glare hazard assessment, the tool determines the retinal irradiance (W/cm2)more » and subtended source angle for an observer and plots the glare source on a hazard spectrum (i.e., low-potential for flash blindness impact, potential for flash blindness impact, retinal burn). For flux mapping, the tool provides a colored map of the receiver scaled by incident solar flux (W/m2) and unwraps the physical dimensions of the receiver while accounting for the perspective of the photographer (e.g., for a flux map of a cylindrical receiver, the horizontal axis denotes receiver angle in degrees and the vertical axis denotes vertical position in meters; for a flat panel receiver, the horizontal axis denotes horizontal position in meters and the vertical axis denotes vertical position in meters). The flux mapping capability also allows the user to specify transects along which the program plots incident solar flux on the receiver.« less

  5. Flux growth utilizing the reaction between flux and crucible

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

    Yan, J. -Q.

    2015-01-22

    Flux growth involves dissolving the components of the target compound in an appropriate flux at high temperatures and then crystallizing under supersaturation controlled by cooling or evaporating the flux. A refractory crucible is generally used to contain the high temperature melt. Moreover, the reaction between the melt and crucible materials can modify the composition of the melt, which typically results in growth failure, or contaminates the crystals. Thus one principle in designing a flux growth is to select suitable flux and crucible materials thus to avoid any reaction between them. In this paper, we review two cases of flux growthmore » in which the reaction between flux and Al2O3 crucible tunes the oxygen content in the melt and helps the crystallization of desired compositions. For the case of La5Pb3O, the Al2O3 crucible oxidizes La to form a passivating La2O3 layer which not only prevents further oxidization of La in the melt but also provides [O] to the melt. Finally, in the case of La0.4Na0.6Fe2As2, it is believed that the Al2O3 crucible reacts with NaAsO2 and the reaction consumes oxygen in the melt thus maintaining an oxygen-free environment.« less

  6. Optimum focusing of Gaussian laser beams: Beam waist shift in spot size minimization

    SciTech Connect (OSTI)

    Li, Y.; Katz, J. )

    1994-04-01

    Optimum focusing of Gaussian laser beams is first discussed by Dickson, who described the change in beam radius under the effect of focusing system parameters. The purpose of this study is to present a formulation for calculating the waist shift under various optimum conditions. Because the variations of beam waist can be measured directly, the waist shift in a focused Gaussian beam is a more practical parameter than the movement of the intensity maximum that is the subject for investigators of the well-known focal shift problem.

  7. An advective atmospheric mixed layer model for ocean modeling purposes: Global simulation of surface heat fluxes

    SciTech Connect (OSTI)

    Seager, jR., Benno Blumenthal, M.; Kushnir, Y.

    1995-08-01

    A simple model of the lowest layer of the atmosphere is developed for coupling to ocean models used to simulate sea surface temperature (SST). The model calculates the turbulent fluxes of sensible and latent heat in terms of variables that an ocean model either calculates (SST) or is forced by (winds). It is designed to avoid the need to specify observed atmospheric data (other than surface winds), or the SST, in the surface flux calculations of ocean models and, hence, to allow a realistic representation of the feedbacks between SST and the fluxes. The modeled layer is considered to be either a dry convective layer or the subcloud layer that underlies marine clouds. The turbulent fluxes are determined through a balance of horizontal advection and diffusion, the surface flux and the flux at the mixed layer top, and, for temperature, radiative cooling. Reasonable simulations of the global distribution of latent and sensible heat flux are obtained. This includes the large fluxes that occur east of the Northern Hemisphere continents in winter that were found to be related to both diffusion (taken to be a parameterization of baroclinic eddies) and advection of cold, dry air from the continent. However, east of North America during winter the sensible heat flux is underestimated and, generally, the region of enhanced fluxes does not extend far enough east compared to observations. Reasons for these discrepancies are discussed and remedies suggested. 47 refs., 10 figs.

  8. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  9. Telecommunication using muon beams

    DOE Patents [OSTI]

    Arnold, Richard C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

  10. Ion Beam Materials Lab

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

    Ion Beam Materials Lab Ion Beam Materials Lab A new research frontier awaits! Our door is open and we thrive on mutually beneficial partnerships, collaborations that drive innovations and new technologies. April 12, 2012 Ion Beam Danfysik Implanter High Voltage Terminal. Contact Yongqiang Wang (505) 665-1596 Email Devoted to the characterization and modification of surfaces through the use of ion beams The Ion Beam Materials Laboratory (IBML) is a Los Alamos National Laboratory resource devoted

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

    SciTech Connect (OSTI)

    Xufei, X. Fan, T.; Nocente, M.; Gorini, G.; Bonomo, F.; Franzen, P.; Fröschle, M.; Grosso, G.; Tardocchi, M.; Grünauer, F.; Pasqualotto, R.

    2014-11-15

    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.

  12. BEAM HALO IN PROTON LINAC BEAMS

    SciTech Connect (OSTI)

    T. WANGLER; K. CRANDALL

    2000-08-01

    In this paper we review the present picture of km halo in proton linacs. Space-charge forces acting in mismatched beams have been identified as a major cause of beam-halo. We present a definition of halo based on a ratio of moments of the distribution of the beam coordinates. We find from our initial studies that for halo detined in this way, a beam can have rms emittance growth without halo growth, but halo growth is always accompanied by rms emittance growth. We describe the beam-halo experiment that is in preparation at Los Alamos, which will address questions about the beam profiles, maximum particle amplitudes, and rms emittance growth associated with the halo.

  13. Theoretical analysis of integral neutron transport equation using collision probability method with quadratic flux approach

    SciTech Connect (OSTI)

    Shafii, Mohammad Ali Meidianti, Rahma Wildian, Fitriyani, Dian; Tongkukut, Seni H. J.; Arkundato, Artoto

    2014-09-30

    Theoretical analysis of integral neutron transport equation using collision probability (CP) method with quadratic flux approach has been carried out. In general, the solution of the neutron transport using the CP method is performed with the flat flux approach. In this research, the CP method is implemented in the cylindrical nuclear fuel cell with the spatial of mesh being conducted into non flat flux approach. It means that the neutron flux at any point in the nuclear fuel cell are considered different each other followed the distribution pattern of quadratic flux. The result is presented here in the form of quadratic flux that is better understanding of the real condition in the cell calculation and as a starting point to be applied in computational calculation.

  14. ARM - Measurement - Soil moisture flux

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

    moisture flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Soil moisture flux A quantity measured according to the formula B = {lambda}(dq/dz), where {lambda} is the conductivity of the soil that the moisture is moving through. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file

  15. Original Impact Calculations

    Broader source: Energy.gov [DOE]

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

  16. Design of a Modular E-Core Flux Concentrating Axial Flux Machine...

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

    Design of a Modular E-Core Flux Concentrating Axial Flux Machine Preprint Tausif Husain, 1 ... Design of a Modular E-Core Flux Concentrating Axial Flux Machine Tausif Husain (1) Yilmaz ...

  17. ION BEAM COLLIMATOR

    DOE Patents [OSTI]

    Langsdorf, A.S. Jr.

    1957-11-26

    A device is described for defining a beam of high energy particles wherein the means for defining the beam in the horizontal and vertical dimension are separately adjustable and the defining members are internally cooled. In general, the device comprises a mounting block having a central opening through which the beam is projected, means for rotatably supporting two pairs of beam- forming members, passages in each member for the flow of coolant; the beam- forming members being insulated from each other and the block, and each having an end projecting into the opening. The beam-forming members are adjustable and may be cooperatively positioned to define the beam passing between the end of the members. To assist in projecting and defining the beam, the member ends have individual means connected thereto for indicating the amount of charge collected thereon due to beam interception.

  18. Flux growth utilizing the reaction between flux and crucible

    SciTech Connect (OSTI)

    Yan, J. -Q.

    2015-01-22

    Flux growth involves dissolving the components of the target compound in an appropriate flux at high temperatures and then crystallizing under supersaturation controlled by cooling or evaporating the flux. A refractory crucible is generally used to contain the high temperature melt. Moreover, the reaction between the melt and crucible materials can modify the composition of the melt, which typically results in growth failure, or contaminates the crystals. Thus one principle in designing a flux growth is to select suitable flux and crucible materials thus to avoid any reaction between them. In this paper, we review two cases of flux growth in which the reaction between flux and Al2O3 crucible tunes the oxygen content in the melt and helps the crystallization of desired compositions. For the case of La5Pb3O, the Al2O3 crucible oxidizes La to form a passivating La2O3 layer which not only prevents further oxidization of La in the melt but also provides [O] to the melt. Finally, in the case of La0.4Na0.6Fe2As2, it is believed that the Al2O3 crucible reacts with NaAsO2 and the reaction consumes oxygen in the melt thus maintaining an oxygen-free environment.

  19. Beam position monitor

    DOE Patents [OSTI]

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

    2003-07-22

    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.

  20. Pyramid beam splitter

    DOE Patents [OSTI]

    McKeown, Mark H.; Beason, Steven C.; Fairer, George

    1992-01-01

    The apparatus of the present invention provides means for obtaining accurate, dependable, measurement of bearings and directions for geologic mapping in subterranean shafts, such as, for example, nuclear waste storage investigations. In operation, a laser beam is projected along a reference bearing. A pyramid is mounted such that the laser beam is parallel to the pyramid axis and can impinge on the apex of the pyramid thus splitting the beam several ways into several beams at right angles to each other and at right angles to the reference beam. The pyramid is also translatable and rotatable in a plane perpendicular to the reference beam.

  1. W-Band Sheet Beam Klystron Simulation

    SciTech Connect (OSTI)

    Colby, E.R.; Caryotakis, G.; Fowkes, W.R.; /SLAC; Smithe, D.N.; /Mission Res., Newington

    2005-09-12

    With the development of ever higher energy particle accelerators comes the need for compactness and high gradient, which in turn require very high frequency high power rf sources. Recent development work in W-band accelerating techniques has spurred the development of a high-power W-band source. Axisymmetric sources suffer from fundamental power output limitations (P{sub sat} {approx} {lambda}{sup 2}) brought on by the conflicting requirements of small beam sizes and high beam current. The sheet beam klystron allows for an increase in beam current without substantial increase in the beam current density, allowing for reduced cathode current densities and focusing field strengths. Initial simulations of a 20:1 aspect ratio sheet beam/cavity interaction using the 3 dimensional particle-in-cell code Magic3D have demonstrated a 35% beam-power to RF power extraction efficiency. Calculational work and numerical simulations leading to a prototype W-band sheet beam klystron will be presented, together with preliminary cold test structure studies of a proposed RF cavity geometry.

  2. W-band sheet beam klystron simulation

    SciTech Connect (OSTI)

    Colby, E.R.; Caryotakis, G.; Fowkes, W.R. [Stanford Linear Accelerator Center, 2575 Sand Hill Rd., Menlo Park, California 94025 (United States); Smithe, D.N. [Mission Research Corporation, 8560 Cinderbed Road, Ste. 700, Newington, Virginia 22122 (United States)

    1999-05-01

    With the development of ever higher energy particle accelerators comes the need for compactness and high gradient, which in turn require very high frequency high power rf sources. Recent development work in W-band accelerating techniques has spurred the development of a high-power W-band source. Axisymmetric sources suffer from fundamental power output limitations (P{sub sat}{approximately}{lambda}{sup 2}) brought on by the conflicting requirements of small beam sizes and high beam current. The sheet beam klystron allows for an increase in beam current without substantial increase in the beam current density, allowing for reduced cathode current densities and focussing field strengths. Initial simulations of a 20:1 aspect ratio sheet beam/cavity interaction using the 3 dimensional particle-in-cell code Magic3D have demonstrated a 35{percent} beam-power to RF power extraction efficiency. Calculational work and numerical simulations leading to a prototype W-band sheet beam klystron will be presented, together with preliminary cold test structure studies of a proposed RF cavity geometry. {copyright} {ital 1999 American Institute of Physics.}

  3. AmeriFlux US-Sta Saratoga

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

    Ewers, Brent [University of Wyoming; Pendall, Elise [University of Wyoming

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Sta Saratoga. Site Description - Sagebrush steppe ecosystem

  4. AmeriFlux US-Wdn Walden

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

    Ewers, Brent [University of Wyoming; Pendall, Elise [University of Wyoming

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Wdn Walden. Site Description - Sagebrush steppe ecosystem

  5. Bismuth-induced phase control of GaAs nanowires grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Lu, Zhenyu; Chen, Pingping E-mail: luwei@mail.sitp.ac.cn; Shi, Suixing; Yao, Luchi; Zhou, Xiaohao; Lu, Wei E-mail: luwei@mail.sitp.ac.cn; Zhang, Zhi; Zhou, Chen; Zou, Jin

    2014-10-20

    In this work, the crystal structure of GaAs nanowires grown by molecular beam epitaxy has been tailored only by bismuth without changing the growth temperature and V/III flux ratio. The introduction of bismuth can lead to the formation of zinc-blende GaAs nanowires, while the removal of bismuth changes the structure into a 4H polytypism before it turns back to the wurtzite phase eventually. The theoretical calculation shows that it is the steadiest for bismuth to adsorb on the GaAs(111){sub B} surface compared to the liquid gold catalyst surface and the interface between the gold catalyst droplet and the nanowire, and these adsorbed bismuth could decrease the diffusion length of adsorbed Ga and hence the supersaturation of Ga in the gold catalyst droplet.

  6. Molecular-beam scattering

    SciTech Connect (OSTI)

    Vernon, M.F.

    1983-07-01

    The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N/sub 2/ from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HCl ..-->.. NaCl + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(2/sup 2/P/sub 3/2/) and Na(3/sup 2/P/sub 3/2/) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included.

  7. Design of a differential radiometer for atmospheric radiative flux measurements

    SciTech Connect (OSTI)

    LaDelfe, P.C.; Weber, P.G.; Rodriguez, C.W.

    1994-11-01

    The Hemispherical Optimized NEt Radiometer (HONER) is an instrument under development at the Los Alamos National Laboratory for deployment on an unmanned aerospace vehicle as part of the Atmospheric Radiation Measurements (ARM/UAV) program. HONER is a differential radiometer which will measure the difference between the total upwelling and downwelling fluxes and is intended to provide a means of measuring the atmospheric radiative flux divergence. Unlike existing instruments which measure the upwelling and downwelling fluxes separately, HONER will achieve an optical difference by chopping the two fluxes alternately onto a common pyroelectric detector. HONER will provide data resolved into two spectral bands; one covering the solar dominated region from less than 0.4 micrometer to approximately 4.5 micrometers and the other covering the region from approximately 4.5 micrometers to greater than 50 micrometers, dominated by thermal radiation. The means of separating the spectral regions guarantees seamless summation to calculate the total flux. The fields-of-view are near-hemispherical, upward and downward. The instrument can be converted, in flight, from the differential mode to absolute mode, measuring the upwelling and downwelling fluxes separately and simultaneously. The instrument also features continuous calibration from on-board sources. We will describe the design and operation of the sensor head and the on-board reference sources as well as the means of deployment.

  8. Neutral Beam Excitation

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

    ... the presence of a small fast ion population are one area ... This research is highly relevant to fusion reactors as beam ... 100 A beam of < 200 keV sodium or potassium ions which ...

  9. Improved approximate formulas for flux from cylindrical and rectangular sources

    SciTech Connect (OSTI)

    Wallace, O.J.; Bokharee, S.A.

    1993-03-01

    This report provides two new approximate formulas for the flux at detector points outside the radial and axial extensions of a homogeneous cylindrical source and improved approximate formulas for the flux at points opposite rectangular surface sources. These formulas extend the range of geometries for which analytic approximations may be used by shield design engineers to make rapid scoping studies and check more extensive calculations for reasonableness. These formulas can be used to support skeptical, independent evaluations and are also valuable teaching tools for introducing shield designers to complex shield analyses.

  10. Microsoft Word - beam characterization and verification.doc

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

    Beam Characterization and Verification Detector Components and Arrangement The beam uniformity and flux are determined using an array of five particle detectors. Each detector consists of Bicron BC-400 scintillator, a Bicron BC-634A optical coupling pad, a Hamamatsu R1635 photomultiplier tube, and a Hamamatsu E1761-04 tube base. Four of the detectors are fixed in position as show in Figure 1 and set up to measure beam particle counting rates continuously at four characteristic points, each 1.64

  11. PARTICLE BEAM TRACKING CIRCUIT

    DOE Patents [OSTI]

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  12. Beam Dynamics for ARIA

    SciTech Connect (OSTI)

    Ekdahl, Carl August Jr.

    2014-10-14

    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. Expansion solution of Laplace`s equation: Technique and application to hollow beam gun design

    SciTech Connect (OSTI)

    Jackson, R.H.; Taccetti, J.M.

    1996-12-31

    This paper presents a flexible algorithm for the general calculation of expansion solutions to Laplace`s equation. The limiting factor in application of the technique is shown to be series truncation error and not errors in calculating numerical derivatives. Application of the algorithm to the accurate computation of arbitrary magnetic fields in cylindrical geometry from on-axis or coil data will be presented. For an ideal current loop, magnetic field accuracies of better than 0.01% of the exact elliptic integral solution can be obtained out to approximately 70--80% of the loop radius. Accuracy improves dramatically for radii closer to the axis. Results also is shown for thin current disks, thin solenoids and thick coils. Other aspects of the technique is illustrated by application to the design of a coil system for a hollow beam electron gun. With some reasonable assumptions about the overlay of the electron trajectories and the magnetic flux contours, it is possible to generate an estimate for the on-axis profile of the gun magnetic field. The expansion technique can then be applied to calculate the off-axis field and its impact on the trajectories without assuming any particular coil system. The initial estimate can then be refined and retested. Finally, an optimization technique is used to develop a coil system which closely reproduces the refined field. The results of carrying out this set of calculations on a 150 kV, 20 A hollow electron gun design for an FEL experiment is reported.

  14. Utility Potential Calculator

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

    for Potential Studies in the Northwest V1.0 Utility Potential Calculator V1.0 for Excel 2007 Utility Potential Calculator V1.0 for Excel 2003 Note: BPA developed the Utility...

  15. ARM - Wind Chill Calculations

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

    CalculatorsWind Chill Calculations Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Wind Chill Calculations Wind Chill is the apparent temperature felt on the exposed human body owing to the combination of temperature and wind speed. From 1945 to 2001, Wind Chill was calculated by the Siple

  16. RELAP5 model of the high flux isotope reactor with low enriched fuel thermal flux profiles

    SciTech Connect (OSTI)

    Banfield, J.; Mervin, B.; Hart, S.; Ritchie, J.; Walker, S.; Ruggles, A.; Maldonado, G. I.

    2012-07-01

    The High Flux Isotope Reactor (HFIR) currently uses highly enriched uranium (HEU) fabricated into involute-shaped fuel plates. It is desired that HFIR be able to use low enriched uranium (LEU) fuel while preserving the current performance capability for its diverse missions in material irradiation studies, isotope production, and the use of neutron beam lines for basic research. Preliminary neutronics and depletion simulations of HFIR with LEU fuel have arrived to feasible fuel loadings that maintain the neutronics performance of the reactor. This article illustrates preliminary models developed for the analysis of the thermal-hydraulic characteristics of the LEU core to ensure safe operation of the reactor. The beginning of life (BOL) LEU thermal flux profile has been modeled in RELAP5 to facilitate steady state simulation of the core cooling, and of anticipated and unanticipated transients. Steady state results are presented to validate the new thermal power profile inputs. A power ramp, slow depressurization at the outlet, and flow coast down transients are also evaluated. (authors)

  17. Numerical calculation of the ion polarization in MEIC

    SciTech Connect (OSTI)

    Derbenev, Yaroslav; Lin, Fanglei; Morozov, Vasiliy; Zhang, Yuhong; Kondratenko, Anatoliy; Kondratenko, M A; Filatov, Yury

    2015-09-01

    Ion polarization in the Medium-energy Electron-Ion Collider (MEIC) is controlled by means of universal 3D spin rotators designed on the basis of "weak" solenoids. We use numerical calculations to demonstrate that the 3D rotators have negligible effect on the orbital properties of the ring. We present calculations of the polarization dynamics along the collider's orbit for both longitudinal and transverse polarization directions at a beam interaction point. We calculate the degree of depolarization due to the longitudinal and transverse beam emittances in case when the zero-integer spin resonance is compensated.

  18. High flux solar energy transformation

    DOE Patents [OSTI]

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

    1991-04-09

    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.

  19. ARM - Measurement - Soil heat flux

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

    heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Soil heat flux A quantity measured according to the formula B = {lambda}(dT/dz), where {lambda} is the conductivity of the soil that the heat is moving through. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each

  20. Beta ray flux measuring device

    DOE Patents [OSTI]

    Impink, Jr., Albert J.; Goldstein, Norman P.

    1990-01-01

    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.

  1. High flux solar energy transformation

    DOE Patents [OSTI]

    Winston, Roland; Gleckman, Philip L.; O'Gallagher, Joseph J.

    1991-04-09

    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.

  2. Toward design of the Collider Beam Collimation System

    SciTech Connect (OSTI)

    Drozhdin, A.; Mokhov, N.; Soundranayagam, R.; Tompkins, J.

    1994-02-01

    A multi-component beam collimation system for the Superconducting Super Collider is described. System choice justification and design requirements are presented. System consists of targets, scrapers, and collimators with appropriate cooling and radiation shielding. Each component has an independent control for positioning and aligning with respect to the beam. Results of beam loss distribution, energy deposition calculations, and thermal analyses, as well as cost estimate, are presented.

  3. Neutral beam monitoring

    DOE Patents [OSTI]

    Fink, Joel H.

    1981-08-18

    Method and apparatus for monitoring characteristics of a high energy neutral beam. A neutral beam is generated by passing accelerated ions through a walled cell containing a low energy neutral gas, such that charge exchange neutralizes the high energy ion beam. The neutral beam is monitored by detecting the current flowing through the cell wall produced by low energy ions which drift to the wall after the charge exchange. By segmenting the wall into radial and longitudinal segments various beam conditions are further identified.

  4. BEAM CONTROL PROBE

    DOE Patents [OSTI]

    Chesterman, A.W.

    1959-03-17

    A probe is described for intercepting a desired portion of a beam of charged particles and for indicating the spatial disposition of the beam. The disclosed probe assembly includes a pair of pivotally mounted vanes moveable into a single plane with adjacent edges joining and a calibrated mechanical arrangement for pivoting the vancs apart. When the probe is disposed in the path of a charged particle beam, the vanes may be adjusted according to the beam current received in each vane to ascertain the dimension of the beam.

  5. Beam Characterization at the Neutron Radiography Facility

    SciTech Connect (OSTI)

    Sarah Morgan; Jeffrey King

    2013-01-01

    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.

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

    DOE Patents [OSTI]

    Kearney, Patrick A.; Burkhart, Scott C.

    2003-04-29

    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.

  7. Gated beam imager for heavy ion beams

    SciTech Connect (OSTI)

    Ahle, Larry; Hopkins, Harvey S.

    1998-12-10

    As part of the work building a small heavy-ion induction accelerator ring, or recirculator, at Lawrence Livermore National Laboratory, a diagnostic device measuring the four-dimensional transverse phase space of the beam in just a single pulse has been developed. This device, the Gated Beam Imager (GBI), consists of a thin plate filled with an array of 100-micron diameter holes and uses a Micro Channel Plate (MCP), a phosphor screen, and a CCD camera to image the beam particles that pass through the holes after they have drifted for a short distance. By time gating the MCP, the time evolution of the beam can also be measured, with each time step requiring a new pulse.

  8. Gated beam imager for heavy ion beams

    SciTech Connect (OSTI)

    Ahle, L.; Hopkins, H.S.

    1998-12-01

    As part of the work building a small heavy-ion induction accelerator ring, or recirculator, at Lawrence Livermore National Laboratory, a diagnostic device measuring the four-dimensional transverse phase space of the beam in just a single pulse has been developed. This device, the Gated Beam Imager (GBI), consists of a thin plate filled with an array of 100-micron diameter holes and uses a Micro Channel Plate (MCP), a phosphor screen, and a CCD camera to image the beam particles that pass through the holes after they have drifted for a short distance. By time gating the MCP, the time evolution of the beam can also be measured, with each time step requiring a new pulse. {copyright} {ital 1998 American Institute of Physics.}

  9. Laser diagnostic for high current H{sup {minus}} beams

    SciTech Connect (OSTI)

    Shafer, R.E.

    1998-12-01

    In the last 5 years, significant technology advances have been made in the performance, size, and cost of solid-state diode-pumped lasers. These developments enable the use of compact Q-switched Nd:YAG lasers as a beam diagnostic for high current H{sup {minus}} beams. Because the threshold for photodetachment is only 0.75 eV, and the maximum detachment cross section is 4{times}10{sup {minus}17}cm{sup 2} at 1.5 eV, A 50 mJ/pulse Q-switched Nd:YAG laser can neutralize a significant fraction of the beam in a single 10 ns wide pulse. The neutral beam maintains nearly identical parameters as the parent H{sup {minus}} beam, including size, divergence, energy, energy spread, and phase spread. A dipole magnet can separate the neutral beam from the H{sup {minus}} beam to allow diagnostics on the neutral beam without intercepting the high-current H{sup {minus}} beam. Such a laser system can also be used to extract a low current proton beam, or to induce fluorescence in partially stripped heavy ion beams. Possible beamline diagnostic systems will be reviewed, and the neutral beam yields will be calculated. {copyright} {ital 1998 American Institute of Physics.}

  10. Laser diagnostic for high current H{sup {minus}} beams

    SciTech Connect (OSTI)

    Shafer, R.E.

    1998-05-05

    In the last 5 years, significant technology advances have been made in the performance, size, and cost of solid-state diode-pumped lasers. These developments enable the use of compact Q-switched Nd:YAG lasers as a beam diagnostic for high current H{sup {minus}} beams. Because the threshold for photodetachment is only 0.75 eV, and the maximum detachment cross section is 4 {times} 10{sup {minus}17} cm{sup 2} at 1.5 eV, a 50 mJ/pulse Q-switched Nd:YAG laser can neutralize a significant fraction of the beam in a single 10-ns wide pulse. The neutral beam maintains nearly identical parameters as the parent H{sup {minus}} beam, including size, divergence, energy, energy spread, and phase spread. A dipole magnet can separate the neutral beam from the H{sup {minus}} beam to allow diagnostics on the neutral beam without intercepting the high-current H{sup {minus}} beam. Such a laser system can also be used to extract a low current proton beam, or to induce fluorescence in partially stripped heavy ion beams. Possible beamline diagnostic systems will be reviewed, and the neutral beam yields will be calculated.

  11. Laser diagnostic for high current H{sup -} beams

    SciTech Connect (OSTI)

    Shafer, Robert E.

    1998-12-10

    In the last 5 years, significant technology advances have been made in the performance, size, and cost of solid-state diode-pumped lasers. These developments enable the use of compact Q-switched Nd:YAG lasers as a beam diagnostic for high current H{sup -} beams. Because the threshold for photodetachment is only 0.75 eV, and the maximum detachment cross section is 4x10{sup -17} cm{sup 2} at 1.5 eV, A 50 mJ/pulse Q-switched Nd:YAG laser can neutralize a significant fraction of the beam in a single 10 ns wide pulse. The neutral beam maintains nearly identical parameters as the parent H{sup -} beam, including size, divergence, energy, energy spread, and phase spread. A dipole magnet can separate the neutral beam from the H{sup -} beam to allow diagnostics on the neutral beam without intercepting the high-current H{sup -} beam. Such a laser system can also be used to extract a low current proton beam, or to induce fluorescence in partially stripped heavy ion beams. Possible beamline diagnostic systems will be reviewed, and the neutral beam yields will be calculated.

  12. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, Vincent M.; Martens, Jon S.; Zipperian, Thomas E.

    1995-01-01

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). 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.

  13. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

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

    1995-02-14

    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.

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

    SciTech Connect (OSTI)

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

    1998-05-01

    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.

  15. ARM - Relative Humidity Calculations

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

    CalculatorsRelative Humidity Calculations Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Relative Humidity Calculations Heat Index is an index that combines air temperature and relative humidity to estimate how hot it actually feels. The human body cools off through perspiration, which

  16. 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.

    2009-01-20

    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.

  17. QUANTIFICATION OF HEAT FLUX FROM A REACTING THERMITE SPRAY

    SciTech Connect (OSTI)

    Eric Nixon; Michelle Pantoya

    2009-07-01

    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.

  18. Waste Package Lifting Calculation

    SciTech Connect (OSTI)

    H. Marr

    2000-05-11

    The objective of this calculation is to evaluate the structural response of the waste package during the horizontal and vertical lifting operations in order to support the waste package lifting feature design. The scope of this calculation includes the evaluation of the 21 PWR UCF (pressurized water reactor uncanistered fuel) waste package, naval waste package, 5 DHLW/DOE SNF (defense high-level waste/Department of Energy spent nuclear fuel)--short waste package, and 44 BWR (boiling water reactor) UCF waste package. Procedure AP-3.12Q, Revision 0, ICN 0, calculations, is used to develop and document this calculation.

  19. Calculation note review

    SciTech Connect (OSTI)

    Ramble, A.L.

    1996-09-30

    This document contains a review of the calculation notes which were prepared for the Tank Waste Remediation System Basis for Interim Operation.

  20. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R.

    2003-04-15

    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.

  1. RADIATION DOSE CALCULATION FOR FUEL HANDLING FACILITY CLOSURE CELL EQUIPMENT

    SciTech Connect (OSTI)

    D. Musat

    2005-03-07

    This calculation evaluates the energy deposition rates in silicon, gamma and neutron flux spectra at various locations of interest throughout FHF closure cell. The physical configuration features a complex geometry, with particle flux attenuation of many orders of magnitude that cannot be modeled by computer codes that use deterministic methods. Therefore, in this calculation the Monte Carlo method was used to solve the photon and neutron transport. In contrast with the deterministic methods, Monte Carlo does not solve an explicit transport equation, but rather obtain answers by simulating individual particles, recording the aspects of interest of their average behavior, and estimates the statistical precision of the results.

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

    SciTech Connect (OSTI)

    Lu, Yong; Zhang, Mingliang Gao, Dong

    2014-02-14

    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.

  3. Transmutation calculations for the accelerator transmutation of waste (ATW) program

    SciTech Connect (OSTI)

    Wilson, W.B.; Arthur, E.D.; Bowman, C.D.; Engel, L.N.; England, T.R.; Hughes, H.G.; Lisowski, P.W.; Perry, R.T.

    1991-01-01

    The disposal of radioactive waste by the transmutation of long-lived radionuclides is being considered; now using neutrons produced with an intense beam of 1.6-GeV protons on a Pb-Bi target. Study teams have been active in the areas of accelerator design, beam transport, radiation transport, transmutation, fluid flow and heat transfer, process chemistry and system analyses. Work is of a preliminary and developmental nature. Here we describe these preliminary efforts in transmutation calculations; the tools developed, status of basic nuclear data, and some early results. These calculations require the description of the intensity and spectrum of neutrons produced by the beam, the distribution of nuclides produced in the medium-energy reactions, the transport of particles produced by the beam, the transmutation of the target materials and transmutation products, and the decay properties of the inventory of radionuclides produced.

  4. Particle beam injection system

    DOE Patents [OSTI]

    Jassby, Daniel L.; Kulsrud, Russell M.

    1977-01-01

    This invention provides a poloidal divertor for stacking counterstreaming ion beams to provide high intensity colliding beams. To this end, method and apparatus are provided that inject high energy, high velocity, ordered, atomic deuterium and tritium beams into a lower energy, toroidal, thermal equilibrium, neutral, target plasma column that is magnetically confined along an endless magnetic axis in a strong restoring force magnetic field having helical field lines to produce counterstreaming deuteron and triton beams that are received bent, stacked and transported along the endless axis, while a poloidal divertor removes thermal ions and electrons all along the axis to increase the density of the counterstreaming ion beams and the reaction products resulting therefrom. By balancing the stacking and removal, colliding, strong focused particle beams, reaction products and reactions are produced that convert one form of energy into another form of energy.

  5. Beam Instrumentation Workshop

    SciTech Connect (OSTI)

    Shafer, R.E. )

    1994-01-01

    The fifth annual Beam Instrumentation Workshop was hosted by Los Alamos National Laboratory in Santa Fe, New Mexico. These proceedings represent the papers presented at the Workshop. A variety of topics were covered including beam emittance diagnostics, fluorescent screens, control systems for many accelerators and photon sources. Beam monitoring was discussed in great detail. There were thirty seven papers presented at the Workshop and all have been abstracted for the Energy and Science Technology database. (AIP)

  6. Draft PEI Calculator

    Broader source: Energy.gov [DOE]

    This Excel spreadsheet is designed to perform the calculations necessary to determine PEI -- a pump's energy index -- as proposed in DOE's Notices of Proposed Rulemaking (Dockets EERE-2011-BT-STD-0031 and EERE-2013-BT-TP-0055). DOE is providing this calculator as a convenience at the request of interested parties.

  7. Broad beam ion implanter

    DOE Patents [OSTI]

    Leung, K.N.

    1996-10-08

    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. 6 figs.

  8. Broad beam ion implanter

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    1996-01-01

    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.

  9. Accelerators AND Beams

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

    ... to energies far higher than usually found on earth. ... Implanting them very precisely in metal surfaces means ... of a Facility for Rare Isotope Beams (FRIB), an ...

  10. Beam Stability Complaint Form

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

    For New Users For Current Users For Administrators MX Users APS User Portal APS Data Management Practices Find a Beamline Apply for Beam Time ESAF Contacts Calendars User...

  11. Multiple Electron Stripping of Heavy Ion Beams

    SciTech Connect (OSTI)

    D. Mueller; L. Grisham; I. Kaganovich; R. L. Watson; V. Horvat; K. E. Zaharakis; Y. Peng

    2002-06-25

    One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 Mev/amu with charge state 1 currently do not exist. Hence, the stripping cross-sections used to model the performance of heavy ion fusion driver beams have, up to now, been based upon theoretical calculations. We have investigated experimentally the stripping of 3.4 Mev/amu Kr 7+ and Xe +11 in N2; 10.2 MeV/amu Ar +6 in He, N2, Ar and Xe; 19 MeV/amu Ar +8 in He, N2, Ar and Xe; 30 MeV He 1 + in He, N2, Ar and Xe; and 38 MeV/amu N +6 in He, N2, Ar and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

  12. A dynamic focusing x-ray monochromator for a wiggler beam line at the SRS of the SERC Daresbury Laboratory

    SciTech Connect (OSTI)

    De Bruijn, D.; Van Zuylen, P. ); Kruizinga, G. , P.O. Box 93138, 2509 AC Den Haag State University of Utrecht, Sorbonnelaan 16, 3508 TB Utrecht )

    1992-01-01

    A Si(220) double-crystal monochromator for the energy range 10--30 keV is presented. It will be used for EXAFS as well as powder diffraction measurements. To determine the requirements for this monochromator we looked, apart from mean considerations, at the requirements dictated by EXAFS in transmission mode. For good data analyses the proper shape, amplitude, and location at the energy axis of each wiggle is required. Moreover it is essential to separate the wiggles from background and noise. For the latter a high flux through the sample is desirable, which can be achieved by horizontal focusing of the beam. For that we have chosen to bend the second crystal sagitally. The sagittal bending radius is adjustable between 50 and 0.8 m, because for different energies different sagittal radii are necessary to focus the beam on the sample. The mean meridional radius of the second crystal is fixed at 130 m, which is an optimization for 20 keV. The meridional radius of the first crystal can be tuned between 100 and 500 m. When this radius is set to 130 m the energy resolution is calculated to be 6, 3, and 35 eV for 10, 20, and 30 keV (for perfectly bent crystals). By changing the meridional radius of the first crystal, future users of this monochromator can make the trade off between resolution and intensity. Movement of the monochromator exit beam, during a scan, will occur due to the monochromator geometry, but is reduced as much as possible by using an asymmetrically cut second crystal, with an asymmetry angle of 2.5{degree}. The average exit beam movement of the monochromator for a 1-keV scan is 20 {mu}m. For 40% of the energy range (10--30 keV) the exit beam position remains within 10 {mu}m. For the second crystal no translation stage is used.

  13. Influence of wind speed averaging on estimates of dimethylsulfide emission fluxes

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

    Chapman, E. G.; Shaw, W. J.; Easter, R. C.; Bian, X.; Ghan, S. J.

    2002-12-03

    The effect of various wind-speed-averaging periods on calculated DMS emission fluxes is quantitatively assessed. Here, a global climate model and an emission flux module were run in stand-alone mode for a full year. Twenty-minute instantaneous surface wind speeds and related variables generated by the climate model were archived, and corresponding 1-hour-, 6-hour-, daily-, and monthly-averaged quantities calculated. These various time-averaged, model-derived quantities were used as inputs in the emission flux module, and DMS emissions were calculated using two expressions for the mass transfer velocity commonly used in atmospheric models. Results indicate that the time period selected for averaging wind speedsmore » can affect the magnitude of calculated DMS emission fluxes. A number of individual marine cells within the global grid show DMS emissions fluxes that are 10-60% higher when emissions are calculated using 20-minute instantaneous model time step winds rather than monthly-averaged wind speeds, and at some locations the differences exceed 200%. Many of these cells are located in the southern hemisphere where anthropogenic sulfur emissions are low and changes in oceanic DMS emissions may significantly affect calculated aerosol concentrations and aerosol radiative forcing.« less

  14. MONO: A program to calculate synchrotron beamline monochromator throughputs

    SciTech Connect (OSTI)

    Chapman, D.

    1989-01-01

    A set of Fortran programs have been developed to calculate the expected throughput of x-ray monochromators with a filtered synchrotron source and is applicable to bending magnet and wiggler beamlines. These programs calculate the normalized throughput and filtered synchrotron spectrum passed by multiple element, flat un- focussed monochromator crystals of the Bragg or Laue type as a function of incident beam divergence, energy and polarization. The reflected and transmitted beam of each crystal is calculated using the dynamical theory of diffraction. Multiple crystal arrangements in the dispersive and non-dispersive mode are allowed as well as crystal asymmetry and energy or angle offsets. Filters or windows of arbitrary elemental composition may be used to filter the incident synchrotron beam. This program should be useful to predict the intensities available from many beamline configurations as well as assist in the design of new monochromator and analyzer systems. 6 refs., 3 figs.

  15. Vertical transport and sources in flux models

    SciTech Connect (OSTI)

    Canavan, G.H.

    1997-01-01

    Vertical transport in flux models in examined and shown to reproduce expected limits for densities and fluxes. Disparities with catalog distributions are derived and inverted to find the sources required to rectify them.

  16. Dose Calculation Spreadsheet

    Energy Science and Technology Software Center (OSTI)

    1997-06-10

    VENTSAR XL is an EXCEL Spreadsheet that can be used to calculate downwind doses as a result of a hypothetical atmospheric release. Both building effects and plume rise may be considered. VENTSAR XL will run using any version of Microsoft EXCEL version 4.0 or later. Macros (the programming language of EXCEL) was used to automate the calculations. The user enters a minimal amount of input and the code calculates the resulting concentrations and doses atmore » various downwind distances as specified by the user.« less

  17. High-flux solar photon processes

    SciTech Connect (OSTI)

    Lorents, D C; Narang, S; Huestis, D C; Mooney, J L; Mill, T; Song, H K; Ventura, S

    1992-06-01

    This study was commissioned by the National Renewable Energy Laboratory (NREL) for the purpose of identifying high-flux photoprocesses that would lead to beneficial national and commercial applications. The specific focus on high-flux photoprocesses is based on the recent development by NREL of solar concentrator technology capable of delivering record flux levels. We examined photolytic and photocatalytic chemical processes as well as photothermal processes in the search for processes where concentrated solar flux would offer a unique advantage. 37 refs.

  18. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, Bruce E. (Livermore, CA); Duncan, David B. (Auburn, CA)

    1994-01-01

    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).

  19. Laser beam generating apparatus

    DOE Patents [OSTI]

    Warner, Bruce E. (Livermore, CA); Duncan, David B. (Auburn, CA)

    1993-01-01

    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).

  20. Laser beam generating apparatus

    DOE Patents [OSTI]

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

    1994-02-15

    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.

  1. Laser beam generating apparatus

    DOE Patents [OSTI]

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

    1993-12-28

    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.

  2. Picosecond beam monitor

    DOE Patents [OSTI]

    Schutt, D.W.; Beck, G.O.

    1974-01-01

    The current in the beam of a particle accelerator is monitored with picosecond resolution by causing the beam to impinge upon the center conductor of a coaxial line, generating a pulse of electromagnetic energy in response thereto. This pulse is detected by means such as a sampling oscilloscope. (Official Gazette)

  3. Vehicle Cost Calculator

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Annual Fuel Cost gal Annual GHG Emissions (lbs of CO2) Vehicle Cost Calculator See Assumptions and Methodology Back Next U.S. Department of Energy Energy Efficiency and ...

  4. ARM - Heat Index Calculations

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

    Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Heat Index Calculations Heat Index is an index that ...

  5. Appliance Energy Calculator

    Broader source: Energy.gov [DOE]

    Our appliance and electronic energy use calculator allows you to estimate your annual energy use and cost to operate specific products. The wattage values provided are samples only; actual wattage...

  6. Beam director design report

    SciTech Connect (OSTI)

    Younger, F.C.

    1986-08-01

    A design and fabrication effort for a beam director is documented. The conceptual design provides for the beam to pass first through a bending and focusing system (or ''achromat''), through a second achromat, through an air-to-vacuum interface (the ''beam window''), and finally through the vernier steering system. Following an initial concept study for a beam director, a prototype permanent magnet 30/sup 0/ beam-bending achromat and prototype vernier steering magnet were designed and built. In volume II, copies are included of the funding instruments, requests for quotations, purchase orders, a complete set of as-built drawings, magnetic measurement reports, the concept design report, and the final report on the design and fabrication project. (LEW)

  7. Laser beam alignment system

    DOE Patents [OSTI]

    Kasner, William H.; Racki, Daniel J.; Swenson, Clark E.

    1984-01-01

    A plurality of pivotal reflectors direct a high-power laser beam onto a workpiece, and a rotatable reflector is movable to a position wherein it intercepts the beam and deflects a major portion thereof away from its normal path, the remainder of the beam passing to the pivotal reflectors through an aperture in the rotating reflector. A plurality of targets are movable to positions intercepting the path of light traveling to the pivotal reflectors, and a preliminary adjustment of the latter is made by use of a low-power laser beam reflected from the rotating reflector, after which the same targets are used to make a final adjustment of the pivotal reflectors with the portion of the high-power laser beam passed through the rotating reflector.

  8. Apparatus for measuring a flux of neutrons

    DOE Patents [OSTI]

    Stringer, James L.

    1977-01-01

    A flux of neutrons is measured by disposing a detector in the flux and applying electronic correlation techniques to discriminate between the electrical signals generated by the neutron detector and the unwanted interfering electrical signals generated by the incidence of a neutron flux upon the cables connecting the detector to the electronic measuring equipment at a remote location.

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

    SciTech Connect (OSTI)

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

    1994-01-01

    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.

  10. Electron Lens for Beam-Beam Compensation at LHC

    SciTech Connect (OSTI)

    Valishev, A.; Shiltsev, V.; /Fermilab

    2009-05-01

    Head-on beam-beam effect may become a major performance limitation for the LHC in some of the upgrade scenarios. Given the vast experience gained from the operation of Tevatron electron lenses, a similar device provides significant potential for mitigation of beam-beam effects at the LHC. In this report we present the results of simulation studies of beam-beam compensation and analyze potential application of electron lense at LHC and RHIC.

  11. The fluxes of CN neutrinos from the Sun in case of mixing in a spherical layer in the solar core

    SciTech Connect (OSTI)

    Kopylov, Anatoly; Petukhov, Valery E-mail: beril@inr.ru

    2012-03-01

    The results of the calculation are presented for the fluxes of CN neutrinos from the Sun in case of mixing in a spherical layer in the solar core, consistent with the seismic data and with the measured solar neutrino fluxes. It is shown that a substantial increase of the flux of {sup 13}N neutrinos can be gained in this case. The possible implications for experiment are discussed.

  12. STUDY OF ELECTRON -PROTON BEAM-BEAM INTERACTION IN ERHIC

    SciTech Connect (OSTI)

    HAO,Y.; LITVINENKO, V.N.; MONTAG, C.; POZDEYEV, E.; PTITSYN, V.

    2007-06-25

    Beam-beam effects present one of major factors limiting the luminosity of colliders. In the linac-ring option of eRHIC design, an electron beam accelerated in a superconducting energy recovery linac collides with a proton beam circulating in the RHIC ring. There are some features of beam-beam effects, which require careful examination in linac-ring configuration. First, the beam-beam interaction can induce specific head-tail type instability of the proton beam referred to as a ''kink'' instability. Thus, beam stability conditions should be established to avoid proton beam loss. Also, the electron beam transverse disruption by collisions has to be evaluated to ensure beam quality is good enough for the energy recovery pass. In addition, fluctuations of electron beam current and/or electron beam size, as well as transverse offset, can cause proton beam emittance growth. The tolerances for those factors should be determined and possible countermeasures should be developed to mitigate the emittance growth. In this paper, a soft Gaussian strong-strong simulation is used to study all of mentioned beam-beam interaction features and possible techniques to reduce the emittance growth.

  13. Measurements and simulations of focused beam for orthovoltage therapy

    SciTech Connect (OSTI)

    Abbas, Hassan; Mahato, Dip N.; Satti, Jahangir; MacDonald, C. A.

    2014-04-15

    Purpose: Megavoltage photon beams are typically used for therapy because of their skin-sparing effect. However, a focused low-energy x-ray beam would also be skin sparing, and would have a higher dose concentration at the focal spot. Such a beam can be produced with polycapillary optics. MCNP5 was used to model dose profiles for a scanned focused beam, using measured beam parameters. The potential of low energy focused x-ray beams for radiation therapy was assessed. Methods: A polycapillary optic was used to focus the x-ray beam from a tungsten source. The optic was characterized and measurements were performed at 50 kV. PMMA blocks of varying thicknesses were placed between optic and the focal spot to observe any variation in the focusing of the beam after passing through the tissue-equivalent material. The measured energy spectrum was used to model the focused beam in MCNP5. A source card (SDEF) in MCNP5 was used to simulate the converging x-ray beam. Dose calculations were performed inside a breast tissue phantom. Results: The measured focal spot size for the polycapillary optic was 0.2 mm with a depth of field of 5 mm. The measured focal spot remained unchanged through 40 mm of phantom thickness. The calculated depth dose curve inside the breast tissue showed a dose peak several centimeters below the skin with a sharp dose fall off around the focus. The percent dose falls below 10% within 5 mm of the focus. It was shown that rotating the optic during scanning would preserve the skin-sparing effect of the focused beam. Conclusions: Low energy focused x-ray beams could be used to irradiate tumors inside soft tissue within 5 cm of the surface.

  14. Influence of transverse diffusion within the proton beam fast-ignitor scenario

    SciTech Connect (OSTI)

    Barriga-Carrasco, Manuel D.; Maynard, Gilles; Kurilenkov, Yuri K.

    2004-12-01

    Fast ignition of an inertial confinement fusion target by an energetic proton beam is here re-examined. We put special emphasis on the role of the transverse dispersion of the beam induced during its travel between the proton source and the compressed deuterium-tritium (DT) fuel. The theoretical model and the computer code used in our calculations are presented. Different beam initial energy distributions are analyzed. We found that the beam exhibits small collective effects while multiple scattering collisions provide a substantial transverse dispersion of the beam. Therefore, the nuclear dispersion imposes severe restrictions on the schemes for fast ignitor even considering an ideal monoenergetic and noncorrelated proton beam.

  15. High bandwidth beam current monitor

    SciTech Connect (OSTI)

    Baltrusaitis, R.M.; Ekdahl, C.A. ); Cooper, R.G. . Santa Barbara Operations); Peterson, E.; Warn, C.E. . Las Vegas Operations)

    1993-01-01

    A stripline directional coupler beam current monitor capable of measuring the time structure of a 30-ps electron beam bunch has been developed. The time response performance of the monitor compares very well with Cherenkov light produced in quartz by the electron beam. The four-pickup monitor is now used on a routine basis for measuring the beam duration, tuning for optimized beam bunching, and centering the bunch in the beam pipe.

  16. High bandwidth beam current monitor

    SciTech Connect (OSTI)

    Baltrusaitis, R.M.; Ekdahl, C.A.; Cooper, R.G.; Peterson, E.; Warn, C.E.

    1993-06-01

    A stripline directional coupler beam current monitor capable of measuring the time structure of a 30-ps electron beam bunch has been developed. The time response performance of the monitor compares very well with Cherenkov light produced in quartz by the electron beam. The four-pickup monitor is now used on a routine basis for measuring the beam duration, tuning for optimized beam bunching, and centering the bunch in the beam pipe.

  17. Category:Gas Flux Sampling | Open Energy Information

    Open Energy Info (EERE)

    Gas Flux Sampling Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Gas Flux Sampling page? For detailed information on Gas Flux...

  18. Ion beam lithography system

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-08-02

    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.

  19. Jobs Calculator | Department of Energy

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

    Jobs Calculator Jobs Calculator owip_jobs_calculator_v11-0.xls (1.46 MB) More Documents & Publications WPN 10-14: Calculation of Job Creation through DOE Recovery Act Funding Progress Report Template Job Counting Guidelines

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

    SciTech Connect (OSTI)

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

    2009-02-01

    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.

  1. LEDA BEAM DIAGNOSTICS INSTRUMENTATION: BEAM POSITION MONITORS

    SciTech Connect (OSTI)

    D. BARR; ET AL

    2000-05-01

    The Low Energy Demonstration Accelerator (LEDA) facility located at Los Alamos National Laboratory (LANL) accelerates protons to an energy of 6.7-MeV and current of 100-mA operating in either a pulsed or cw mode. Of key importance to the commissioning and operations effort is the Beam Position Monitor system (BPM). The LEDA BPM system uses five micro-stripline beam position monitors processed by log ratio processing electronics with data acquisition via a series of custom TMS32OC40 Digital Signal Processing (DSP) boards. Of special interest to this paper is the operation of the system, the log ratio processing, and the system calibration technique. This paper will also cover the DSP system operations and their interaction with the main accelerator control system.

  2. Geothermal Life Cycle Calculator

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

    Sullivan, John

    2014-03-11

    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 DOEs 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.

  3. 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 DOEs 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.

  4. Three recent TDHF calculations

    SciTech Connect (OSTI)

    Weiss, M.S.

    1981-05-01

    Three applications of TDHF are discussed. First, vibrational spectra of a post grazing collision /sup 40/Ca nucleus is examined and found to contain many high energy components, qualitatively consistent with recent Orsay experiments. Second, the fusion cross section in energy and angular momentum are calculated for /sup 16/O + /sup 24/Mg to exhibit the parameters of the low l window for this system. A sensitivity of the fusion cross section to the effective two body potential is discussed. Last, a preliminary analysis of /sup 86/Kr + /sup 139/La at E/sub lab/ = 505 MeV calculated in the frozen approximation is displayed, compared to experiment and discussed.

  5. Geothermal Life Cycle Calculator

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

    Sullivan, John

    2014-03-11

    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. Neutral particle beam intensity controller

    DOE Patents [OSTI]

    Dagenhart, W.K.

    1984-05-29

    The neutral beam intensity controller is based on selected magnetic defocusing of the ion beam prior to neutralization. The defocused portion of the beam is dumped onto a beam dump disposed perpendicular to the beam axis. Selective defocusing is accomplished by means of a magnetic field generator disposed about the neutralizer so that the field is transverse to the beam axis. The magnetic field intensity is varied to provide the selected partial beam defocusing of the ions prior to neutralization. The desired focused neutral beam portion passes along the beam path through a defining aperture in the beam dump, thereby controlling the desired fraction of neutral particles transmitted to a utilization device without altering the kinetic energy level of the desired neutral particle fraction. By proper selection of the magnetic field intensity, virtually zero through 100% intensity control of the neutral beam is achieved.

  7. Beam! Magic! | Jefferson Lab

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

    with all the changes, the accelerator can be made to work. Beam Since my first serious introduction to nuclear and particle physics - when I worked for a few weeks one summer at...

  8. Focused ion beam system

    DOE Patents [OSTI]

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

    1999-08-31

    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.

  9. Focused ion beam system

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Gough, Richard A.; Ji, Qing; Lee, Yung-Hee Yvette

    1999-01-01

    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 .mu.m or less.

  10. Tunnel closure calculations

    SciTech Connect (OSTI)

    Moran, B.; Attia, A.

    1995-07-01

    When a deeply penetrating munition explodes above the roof of a tunnel, the amount of rubble that falls inside the tunnel is primarily a function of three parameters: first the cube-root scaled distance from the center of the explosive to the roof of the tunnel. Second the material properties of the rock around the tunnel, and in particular the shear strength of that rock, its RQD (Rock Quality Designator), and the extent and orientation of joints. And third the ratio of the tunnel diameter to the standoff distance (distance between the center of explosive and the tunnel roof). The authors have used CALE, a well-established 2-D hydrodynamic computer code, to calculate the amount of rubble that falls inside a tunnel as a function of standoff distance for two different tunnel diameters. In particular they calculated three of the tunnel collapse experiments conducted in an iron ore mine near Kirkeness, Norway in the summer of 1994. The failure model that they used in their calculations combines an equivalent plastic strain criterion with a maximum tensile strength criterion and can be calibrated for different rocks using cratering data as well as laboratory experiments. These calculations are intended to test and improve the understanding of both the Norway Experiments and the ACE (Array of conventional Explosive) phenomenology.

  11. 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.

  12. Performance and safety parameters for the high flux isotope reactor

    SciTech Connect (OSTI)

    Ilas, G. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States); Primm III, T. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States); Primm Consulting, LLC, 945 Laurel Hill Road, Knoxville, TN 37923 (United States)

    2012-07-01

    A Monte Carlo depletion model for the High Flux Isotope Reactor (HFIR) Cycle 400 and its use in calculating parameters of relevance to the reactor performance and safety during the reactor cycle are presented in this paper. This depletion model was developed to serve as a reference for the design of a low-enriched uranium (LEU) fuel for an ongoing study to convert HFIR from high-enriched uranium (HEU) to LEU fuel; both HEU and LEU depletion models use the same methodology and ENDF/B-VII nuclear data as discussed in this paper. The calculated HFIR Cycle 400 parameters, which are compared with measurement data from critical experiments performed at HFIR, data included in the HFIR Safety Analysis Report (SAR), or data reported by previous calculations, provide a basis for verification or updating of the corresponding SAR data. (authors)

  13. Performance and Safety Parameters for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Ilas, Germina [ORNL; Primm, Trent [Primm Consulting, LLC

    2012-01-01

    A Monte Carlo depletion model for the High Flux Isotope Reactor (HFIR) Cycle 400 and its use in calculating parameters of relevance to the reactor performance and safety during the reactor cycle are presented in this paper. This depletion model was developed to serve as a reference for the design of a low-enriched uranium (LEU) fuel for an ongoing study to convert HFIR from high-enriched uranium (HEU) to LEU fuel; both HEU and LEU depletion models use the same methodology and ENDV/B-VII nuclear data as discussed in this paper. The calculated HFIR Cycle 400 parameters, which are compared when available with measurement data from critical experiments performed at HFIR, data included in the HFIR Safety Analysis Report (SAR), or data reported by previous calculations, provide a basis for verification or updating of the corresponding SAR data.

  14. Plutonium 239 Equivalency Calculations

    SciTech Connect (OSTI)

    Wen, J

    2011-05-31

    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.

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

    SciTech Connect (OSTI)

    Bucholz, J.A.

    2000-07-01

    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.

  16. Method of fission heat flux determination from experimental data

    DOE Patents [OSTI]

    Paxton, Frank A.

    1999-01-01

    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.

  17. Study of heat flux gages using sensitivity analysis

    SciTech Connect (OSTI)

    Dowding, K.J.; Blackwell, B.F.; Cochran, R.J.

    1998-08-01

    The response and operation of a heat flux gage is studied using sensitivity analysis. Sensitivity analysis is the process by which one determines the sensitivity of a model output to changes in the model parameters. This process uses sensitivity coefficients that are defined as partial derivatives of field variables--e.g., temperature--with respect to model parameters--e.g., thermal properties and boundary conditions. Computing sensitivity coefficients, in addition to the response of a heat flux gage, aids in identifying model parameters that significantly impact the temperature response. A control volume, finite element-based code is used to implement numerical sensitivity coefficient calculations, allowing general problems to be studied. Sensitivity coefficients are discussed for the well known Gardon gage.

  18. Electron flux at the surface of titanium tritide films

    SciTech Connect (OSTI)

    Kherani, N.P.; Shmayda, W.T. . Research Center)

    1992-03-01

    Certain metal tritides have been investigated as reliable and quasi-constant sources of electrons for a number of practical purposes with particular attention to the dependence of the electron emission rate as a function of temperature. The objective of this paper is to carry out simple calculations that illustrate the relative ranking of a numbed of binary metal tritides with respect to the maximum achievable electron flux; examine semi-empirically the energy spectrum of the electrons emanating from the surface of a titanium tritide film; and present experimental measurements of the electron emission rate from the surface of titanium tritide films. THe results suggest that beryllium tritide would yield the greatest electron emission rate of all the metal tritides; the emitted flux has a significant component of secondary electrons; and, the total electron emission rate is quite sensitive to the condition of the emitting surface.

  19. Detector dose response in megavoltage small photon beams. II. Pencil beam perturbation effects

    SciTech Connect (OSTI)

    Bouchard, Hugo Duane, Simon; Kamio, Yuji; Palmans, Hugo; Seuntjens, Jan

    2015-10-15

    Purpose: To quantify detector perturbation effects in megavoltage small photon fields and support the theoretical explanation on the nature of quality correction factors in these conditions. Methods: In this second paper, a modern approach to radiation dosimetry is defined for any detector and applied to small photon fields. Fano’s theorem is adapted in the form of a cavity theory and applied in the context of nonstandard beams to express four main effects in the form of perturbation factors. The pencil-beam decomposition method is detailed and adapted to the calculation of perturbation factors and quality correction factors. The approach defines a perturbation function which, for a given field size or beam modulation, entirely determines these dosimetric factors. Monte Carlo calculations are performed in different cavity sizes for different detection materials, electron densities, and extracameral components. Results: Perturbation effects are detailed with calculated perturbation functions, showing the relative magnitude of the effects as well as the geometrical extent to which collimating or modulating the beam impacts the dosimetric factors. The existence of a perturbation zone around the detector cavity is demonstrated and the approach is discussed and linked to previous approaches in the literature to determine critical field sizes. Conclusions: Monte Carlo simulations are valuable to describe pencil beam perturbation effects and detail the nature of dosimetric factors in megavoltage small photon fields. In practice, it is shown that dosimetric factors could be avoided if the field size remains larger than the detector perturbation zone. However, given a detector and beam quality, a full account for the detector geometry is necessary to determine critical field sizes.

  20. FINE-SCALE STRUCTURES OF FLUX ROPES TRACKED BY ERUPTING MATERIAL

    SciTech Connect (OSTI)

    Li Ting; Zhang Jun E-mail: zjun@nao.cas.cn

    2013-06-20

    We present Solar Dynamics Observatory observations of two flux ropes tracked out by material from a surge and a failed filament eruption on 2012 July 29 and August 4, respectively. For the first event, the interaction between the erupting surge and a loop-shaped filament in the east seems to 'peel off' the filament and add bright mass into the flux rope body. The second event is associated with a C-class flare that occurs several minutes before the filament activation. The two flux ropes are, respectively, composed of 85 {+-} 12 and 102 {+-} 15 fine-scale structures, with an average width of about 1.''6. Our observations show that two extreme ends of the flux rope are rooted in opposite polarity fields and each end is composed of multiple footpoints (FPs) of fine-scale structures. The FPs of the fine-scale structures are located at network magnetic fields, with magnetic fluxes from 5.6 Multiplication-Sign 10{sup 18} Mx to 8.6 Multiplication-Sign 10{sup 19} Mx. Moreover, almost half of the FPs show converging motion of smaller magnetic structures over 10 hr before the appearance of the flux rope. By calculating the magnetic fields of the FPs, we deduce that the two flux ropes occupy at least 4.3 Multiplication-Sign 10{sup 20} Mx and 7.6 Multiplication-Sign 10{sup 20} Mx magnetic fluxes, respectively.

  1. Magnetohydrostatic equilibrium. II. Three-dimensional multiple open magnetic flux tubes in the stratified solar atmosphere

    SciTech Connect (OSTI)

    Gent, F. A.; Erdélyi, R.; Fedun, V.

    2014-07-01

    A system of multiple open magnetic flux tubes spanning the solar photosphere and lower corona is modeled analytically, within a realistic stratified atmosphere subject to solar gravity. This extends results for a single magnetic flux tube in magnetohydrostatic equilibrium, described in Gent et al. Self-similar magnetic flux tubes are combined to form magnetic structures, which are consistent with high-resolution observations. The observational evidence supports the existence of strands of open flux tubes and loops persisting in a relatively steady state. Self-similar magnetic flux tubes, for which an analytic solution to the plasma density and pressure distribution is possible, are combined. We calculate the appropriate balancing forces, applying to the equations of momentum and energy conservation to preserve equilibrium. Multiplex flux tube configurations are observed to remain relatively stable for up to a day or more, and it is our aim to apply our model as the background condition for numerical studies of energy transport mechanisms from the solar surface to the corona. We apply magnetic field strength, plasma density, pressure, and temperature distributions consistent with observational and theoretical estimates for the lower solar atmosphere. Although each flux tube is identical in construction apart from the location of the radial axis, combinations can be applied to generate a non-axisymmetric magnetic field with multiple non-uniform flux tubes. This is a considerable step forward in modeling the realistic magnetized three-dimensional equilibria of the solar atmosphere.

  2. Single element laser beam shaper

    DOE Patents [OSTI]

    Zhang, Shukui; Michelle D. Shinn

    2005-09-13

    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.

  3. Photodetachment process for beam neutralization

    DOE Patents [OSTI]

    Fink, J.H.; Frank, A.M.

    1979-02-20

    A process for neutralization of accelerated ions employing photo-induced charge detachment is disclosed. The process involves directing a laser beam across the path of a negative ion beam such as to effect photodetachment of electrons from the beam ions. The frequency of the laser beam employed is selected to provide the maximum cross-section for the photodetachment process. 2 figs.

  4. The Multi-Step CADIS method for shutdown dose rate calculations and uncertainty propagation

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

    Ibrahim, Ahmad M.; Peplow, Douglas E.; Grove, Robert E.; Peterson, Joshua L.; Johnson, Seth R.

    2015-12-01

    Shutdown dose rate (SDDR) analysis requires (a) a neutron transport calculation to estimate neutron flux fields, (b) an activation calculation to compute radionuclide inventories and associated photon sources, and (c) a photon transport calculation to estimate final SDDR. In some applications, accurate full-scale Monte Carlo (MC) SDDR simulations are needed for very large systems with massive amounts of shielding materials. However, these simulations are impractical because calculation of space- and energy-dependent neutron fluxes throughout the structural materials is needed to estimate distribution of radioisotopes causing the SDDR. Biasing the neutron MC calculation using an importance function is not simple becausemore » it is difficult to explicitly express the response function, which depends on subsequent computational steps. Furthermore, the typical SDDR calculations do not consider how uncertainties in MC neutron calculation impact SDDR uncertainty, even though MC neutron calculation uncertainties usually dominate SDDR uncertainty.« less

  5. The Multi-Step CADIS method for shutdown dose rate calculations and uncertainty propagation

    SciTech Connect (OSTI)

    Ibrahim, Ahmad M.; Peplow, Douglas E.; Grove, Robert E.; Peterson, Joshua L.; Johnson, Seth R.

    2015-12-01

    Shutdown dose rate (SDDR) analysis requires (a) a neutron transport calculation to estimate neutron flux fields, (b) an activation calculation to compute radionuclide inventories and associated photon sources, and (c) a photon transport calculation to estimate final SDDR. In some applications, accurate full-scale Monte Carlo (MC) SDDR simulations are needed for very large systems with massive amounts of shielding materials. However, these simulations are impractical because calculation of space- and energy-dependent neutron fluxes throughout the structural materials is needed to estimate distribution of radioisotopes causing the SDDR. Biasing the neutron MC calculation using an importance function is not simple because it is difficult to explicitly express the response function, which depends on subsequent computational steps. Furthermore, the typical SDDR calculations do not consider how uncertainties in MC neutron calculation impact SDDR uncertainty, even though MC neutron calculation uncertainties usually dominate SDDR uncertainty.

  6. Etalon-induced baseline drift and correction in atom flux sensors based on atomic absorption spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20

    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 these sensors are strongly affected by 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, and cannot be corrected using 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.

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

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20

    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. Beam Trail Tracking at Fermilab

    SciTech Connect (OSTI)

    Nicklaus, Dennis J.; Carmichael, Linden Ralph; Neswold, Richard; Yuan, Zongwei

    2015-01-01

    We present a system for acquiring and sorting data from select devices depending on the destination of each particular beam pulse in the Fermilab accelerator chain. The 15 Hz beam that begins in the Fermilab ion source can be directed to a variety of additional accelerators, beam lines, beam dumps, and experiments. We have implemented a data acquisition system that senses the destination of each pulse and reads the appropriate beam intensity devices so that profiles of the beam can be stored and analysed for each type of beam trail. We envision utilizing this data long term to identify trends in the performance of the accelerators

  9. Vehicle Cost Calculator

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Choose a vehicle to compare fuel cost and emissions with a conventional vehicle. Select Fuel/Technology Electric Hybrid Electric Plug-in Hybrid Electric Natural Gas (CNG) Flex Fuel (E85) Biodiesel (B20) Next Vehicle Cost Calculator Update Your Widget Code This widget version will stop working on March 31. Update your widget code. × Widget Code Select All Close U.S. Department of Energy Energy Efficiency and Renewable Energy

  10. Hydrogen Threshold Cost Calculation

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

    Program Record (Offices of Fuel Cell Technologies) Record #: 11007 Date: March 25, 2011 Title: Hydrogen Threshold Cost Calculation Originator: Mark Ruth & Fred Joseck Approved by: Sunita Satyapal Date: March 24, 2011 Description: The hydrogen threshold cost is defined as the hydrogen cost in the range of $2.00-$4.00/gge (2007$) which represents the cost at which hydrogen fuel cell electric vehicles (FCEVs) are projected to become competitive on a cost per mile basis with the competing

  11. Nuclear Material Variance Calculation

    Energy Science and Technology Software Center (OSTI)

    1995-01-01

    MAVARIC (Materials Accounting VARIance Calculations) is a custom spreadsheet that significantly reduces the effort required to make the variance and covariance calculations needed to determine the detection sensitivity of a materials accounting system and loss of special nuclear material (SNM). The user is required to enter information into one of four data tables depending on the type of term in the materials balance (MB) equation. The four data tables correspond to input transfers, output transfers,more » and two types of inventory terms, one for nondestructive assay (NDA) measurements and one for measurements made by chemical analysis. Each data entry must contain an identification number and a short description, as well as values for the SNM concentration, the bulk mass (or solution volume), the measurement error standard deviations, and the number of measurements during an accounting period. The user must also specify the type of error model (additive or multiplicative) associated with each measurement, and possible correlations between transfer terms. Predefined spreadsheet macros are used to perform the variance and covariance calculations for each term based on the corresponding set of entries. MAVARIC has been used for sensitivity studies of chemical separation facilities, fuel processing and fabrication facilities, and gas centrifuge and laser isotope enrichment facilities.« less

  12. Light beam frequency comb generator

    DOE Patents [OSTI]

    Priatko, G.J.; Kaskey, J.A.

    1992-11-24

    A light beam frequency comb generator uses an acousto-optic modulator to generate a plurality of light beams with frequencies which are uniformly separated and possess common noise and drift characteristics. A well collimated monochromatic input light beam is passed through this modulator to produce a set of both frequency shifted and unshifted optical beams. An optical system directs one or more frequency shifted beams along a path which is parallel to the path of the input light beam such that the frequency shifted beams are made incident on the modulator proximate to but separated from the point of incidence of the input light beam. After the beam is thus returned to and passed through the modulator repeatedly, a plurality of mutually parallel beams are generated which are frequency-shifted different numbers of times and possess common noise and drift characteristics. 2 figs.

  13. Light beam frequency comb generator

    DOE Patents [OSTI]

    Priatko, Gordon J.; Kaskey, Jeffrey A.

    1992-01-01

    A light beam frequency comb generator uses an acousto-optic modulator to generate a plurality of light beams with frequencies which are uniformly separated and possess common noise and drift characteristics. A well collimated monochromatic input light beam is passed through this modulator to produce a set of both frequency shifted and unshifted optical beams. An optical system directs one or more frequency shifted beams along a path which is parallel to the path of the input light beam such that the frequency shifted beams are made incident on the modulator proximate to but separated from the point of incidence of the input light beam. After the beam is thus returned to and passed through the modulator repeatedly, a plurality of mutually parallel beams are generated which are frequency-shifted different numbers of times and possess common noise and drift characteristics.

  14. Beam Characterizations at Femtosecond Electron Beam Facility

    SciTech Connect (OSTI)

    Rimjaem, S.; Jinamoon, V.; Kangrang, M.; Kusoljariyakul, K.; Saisut, J.; Thongbai, C.; Vilaithong, T.; Rhodes, M.W.; Wichaisirimongkol, P.; Wiedemann, H.; /SLAC

    2006-03-17

    The SURIYA project at the Fast Neutron Research Facility (FNRF) has been established and is being commissioning to generate femtosecond (fs) electron bunches. Theses short bunches are produced by a system consisting of an S-band thermionic cathode RF-gun, an alpha magnet (a-magnet) serving as a magnetic bunch compressor, and a SLAC-type linear accelerator (linac). The characteristics of its major components and the beam characterizations as well as the preliminary experimental results will be presented and discussed in this paper.

  15. Fluxing agent for metal cast joining

    DOE Patents [OSTI]

    Gunkel, Ronald W.; Podey, Larry L.; Meyer, Thomas N.

    2002-11-05

    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.

  16. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, Henry W.; Hand Jr, Samuel W.; Ksayian, Haig

    1986-02-04

    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.

  17. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, Henry W.; Hand, Jr, Samuel W.; Ksayian, Haig

    1986-01-01

    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.

  18. ICFA Beam Dynamics Newsletter

    SciTech Connect (OSTI)

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

    2012-07-01

    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.

  19. Beam-beam observations in the Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Luo, Y.; Fischer, W.; White, S.

    2015-06-24

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been operating since 2000. Over the past decade, thanks to the continuously increased bunch intensity and reduced β*s at the interaction points, the maximum peak luminosity in the polarized proton operation has been increased by more than two orders of magnitude. In this article, we first present the beam-beam observations in the previous RHIC polarized proton runs. Then we analyze the mechanisms for the beam loss and emittance growth in the presence of beam-beam interaction. The operational challenges and limitations imposed by beam-beam interaction and their remedies are also presented. In the end, we briefly introduce head-on beam-beam compensation with electron lenses in RHIC.

  20. LHC beam-beam compensation studies at RHIC

    SciTech Connect (OSTI)

    Fischer,W.; Abreu, N.; Calaga, R.; Robert-Demolaize, G.; Luo, Y.; Montag, C.

    2009-05-04

    Long-range and head-on beam-beam effects are expected to limit the LHC performance with design parameters. To mitigate long-range effects current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. To reduce the head-on beam-beam effect electron lenses were proposed for both the LHC and RHIC. We present the experimental long-range beam-beam program and report on head-on compensations studies at RHIC, which are based on simulations.

  1. 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.

    2013-04-01

    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.

  2. Laser beam characterization results for a high power CW Nd:YAG laser

    SciTech Connect (OSTI)

    Keicher, D.M.

    1994-12-31

    In an effort to understand multimode laser beam propagation characteristics for better development of laser material processing applications, beam diagnostic experiments were performed on a 1800 watt CW Nd:YAG laser. Beam diameter data were acquired at approximately 12 positions along the beam optical axis about the minimum waist created by a long focal length single element lens at several power levels. These data were then used to evaluate the laser output beam characteristics using two differing techniques. For the ISO technique, two data points from the beam diameter data were used in determining the output laser beam characteristics. These points were the beam minimum waist diameter and the diameter at a point along the beam optical axis where the beam diameter had increased to approximately 0.7 times that of the beam minimum waist diameter. The second analysis technique involved fitting the entire data set to theoretical equations used to describe the multimode laser beam propagation and points from the fitted curve fit were then used to determine the output beam characteristics from the laser. For all power levels evaluated, calculated results predicting the laser beam minimum waist location were in agreement with measured values and more consistent using the curve-fit technique than the two-point evaluation technique.

  3. 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.

    2008-06-23

    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.

  4. Zero Temperature Hope Calculations

    SciTech Connect (OSTI)

    Rozsnyai, B F

    2002-07-26

    The primary purpose of the HOPE code is to calculate opacities over a wide temperature and density range. It can also produce equation of state (EOS) data. Since the experimental data at the high temperature region are scarce, comparisons of predictions with the ample zero temperature data provide a valuable physics check of the code. In this report we show a selected few examples across the periodic table. Below we give a brief general information about the physics of the HOPE code. The HOPE code is an ''average atom'' (AA) Dirac-Slater self-consistent code. The AA label in the case of finite temperature means that the one-electron levels are populated according to the Fermi statistics, at zero temperature it means that the ''aufbau'' principle works, i.e. no a priory electronic configuration is set, although it can be done. As such, it is a one-particle model (any Hartree-Fock model is a one particle model). The code is an ''ion-sphere'' model, meaning that the atom under investigation is neutral within the ion-sphere radius. Furthermore, the boundary conditions for the bound states are also set at the ion-sphere radius, which distinguishes the code from the INFERNO, OPAL and STA codes. Once the self-consistent AA state is obtained, the code proceeds to generate many-electron configurations and proceeds to calculate photoabsorption in the ''detailed configuration accounting'' (DCA) scheme. However, this last feature is meaningless at zero temperature. There is one important feature in the HOPE code which should be noted; any self-consistent model is self-consistent in the space of the occupied orbitals. The unoccupied orbitals, where electrons are lifted via photoexcitation, are unphysical. The rigorous way to deal with that problem is to carry out complete self-consistent calculations both in the initial and final states connecting photoexcitations, an enormous computational task. The Amaldi correction is an attempt to address this problem by distorting the

  5. Calculation of Electron Trajectories

    Energy Science and Technology Software Center (OSTI)

    1982-06-01

    EGUN, the SLAC Electron Trajectory Program, computes trajectories of charged particles in electrostatic and magnetostatic focusing systems including the effects of space charge and self-magnetic fields. Starting options include Child''s Law conditions on cathodes of various shapes, user-specified initial conditions for each ray, and a combination of Child''s Law conditions and user specifications. Either rectangular or cylindrically symmetric geometry may be used. Magnetic fields may be specified using arbitrary configuration of coils, or the outputmore » of a magnet program, such as Poisson, or by an externally calculated array of the axial fields.« less

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

    DOE Patents [OSTI]

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

    2005-12-26

    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.

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

    SciTech Connect (OSTI)

    Zourari, K.; Peppa, V.; Papagiannis, P.; Ballester, Facundo; Siebert, Frank-Andr

    2014-04-15

    Purpose: To provide a method for calculating the transmission of any broad photon beam with a known energy spectrum in the range of 201090 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 (201090 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, 507517 (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, 13981404 (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

  8. SSRL BEAM PORT SCHEDULE

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

    5-1 Nov. 28, 2005 Nov. 29, 2005 Nov. 30, 2005 Dec. 01, 2005 Dec. 02, 2005 Dec. 03, 2005 Dec. 04, 2005 MA FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI BEAM LINE 5-2 Nov. 28, 2005 Nov. 29, 2005 Nov. 30, 2005 Dec. 01, 2005 Dec. 02, 2005 Dec. 03, 2005 Dec. 04, 2005 MA FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI FACI BEAM LINE 5-4 Nov. 28, 2005 Nov. 29, 2005 Nov. 30, 2005 Dec. 01, 2005 Dec. 02,

  9. SSRL BEAM PORT SCHEDULE

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

    7-1 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP BEAM LINE 9-2 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP BEAM LINE 11-1 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov.

  10. SSRL BEAM PORT SCHEDULE

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

    5-4 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP BEAM LINE 8-1 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN Unscheduled Unscheduled DOWN DOWN DOWN DOWN Unscheduled Unscheduled Unscheduled DOWN DOWN DOWN DOWN Unscheduled Unscheduled Unscheduled BEAM LINE 8-2 Nov.

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

    SciTech Connect (OSTI)

    Paynter, D.; Weston, S. J.; Cosgrove, V. P.; Evans, J. A.; Thwaites, D. I.

    2014-05-15

    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

  12. AmeriFlux US-Ivo Ivotuk

    SciTech Connect (OSTI)

    Oechel, Walter; Zona, Donatella

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ivo Ivotuk. Site Description - This site is 300 km south of Barrow and is located at the foothill of the Brooks Range and is classified as tussock sedge, dwarf-shrub, moss tundra.

  13. AmeriFlux US-Atq Atqasuk

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

    Oechel, Walt [San Diego State University; Zona, Donatella [San Diego State University

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Atq Atqasuk. Site Description - This site is 100 km south of Barrow, Alaska, Variety of moist-wet coastal sedge tundra, and moist-tussock tundra surfaces in the more well-drained upland.

  14. AmeriFlux US-Brw Barrow

    SciTech Connect (OSTI)

    Oechel, Walt; Zona, Donatella

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Brw Barrow. Site Description - The local landscape surrounding the Barrow site has a history absent of any disturbances. The terrain was not heavily glaciated during the last period of glaciation. The vegetation is mature in an unmanaged and undisturbed Arctic tundra.

  15. AmeriFlux US-Dia Diablo

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

    Wharton, Sonia [Lawrence Livermore National Laboratory

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Dia Diablo. Site Description - The site is on land owned by Lawrence Livermore National Laboratory (Site 300) and has no grazing or management history since the 1950's except for summer-time burning of selected acres for fire management (not included in the tower footprint).

  16. Ion Beam Analysis of Targets Used in Controlatron Neutron Generators

    SciTech Connect (OSTI)

    Banks, James C.; Doyle, Barney L.; Walla, Lisa A.; Walsh, David S.

    2009-03-10

    Controlatron neutron generators are used for testing neutron detection systems at Sandia National Laboratories. To provide for increased tube lifetimes for the moderate neutron flux output of these generators, metal hydride (ZrT{sub 2}) target fabrication processes have been developed. To provide for manufacturing quality control of these targets, ion beam analysis techniques are used to determine film composition. The load ratios (i.e. T/Zr concentration ratios) of ZrT{sub 2} Controlatron neutron generator targets have been successfully measured by simultaneously acquiring RBS and ERD data using a He{sup ++} beam energy of 10 MeV. Several targets were measured and the film thicknesses obtained from RBS measurements agreed within {+-}2% with Dektak profilometer measurements. The target fabrication process and ion beam analysis techniques will be presented.

  17. Beam position monitor sensitivity for low-{beta} beams

    SciTech Connect (OSTI)

    Shafer, R.E.

    1993-11-01

    At low velocities, the EM field of a particle in a conducting beam tube is no longer a TEM wave, but has a finite longitudinal extent. The net effect of this is to reduce the coupling of the high-frequency Fourier components of the beam current to BPM (beam position monitor) electrodes, which modifies the BPM sensitivity to beam displacement. This effect is especially pronounced for high-frequency, large-aperture pickups used for low-{beta} beams. Non-interceptive beam position monitors used in conjunction with high frequency RFQ (radio-frequency-quadrupole) and DTL (drift-tube-linac) accelerators fall into this category. When testing a BPM with a thin wire excited with either pulses or high-frequency sinusoidal currents, the EM wave represents the principal (TEM) mode in a coaxial transmission line, which is equivalent to a highly relativistic ({beta} = 1) beam. Thus wire measurements are not suitable for simulating slow particle beams in high bandwidth diagnostic devices that couple to the image currents in the beam tube wall. Attempts to load the tin wire either capacitively or inductively to slow the EM wave down have met with limited success. In general, the equations used to represent the 2-D response of cylindrical-geometry BPMs to charged-particle beams make several assumptions: (1) the BPM electrodes are flush with and grounded to the surface of the conducting beam tube; (2) the beam is a line source (pencil beam); (3) the longitudinal extent of the EM field of a beam particle at the beam tube wall is zero, corresponding to a highly relativistic beam. The purpose of this paper is to make some quantitative estimates of the corrections to the conventional approximations when a BPM is used to measure the position of low velocity (low-{beta}) beams.

  18. Sheet beam model for intense space-charge: with application to Debye screening and the distribution of particle oscillation frequencies in a thermal equilibrium beam

    SciTech Connect (OSTI)

    Lund, Steven M.; Friedman, Alex; Bazouin, Guillaume

    2011-01-10

    A one-dimensional Vlasov-Poisson model for sheet beams is reviewed and extended to provide a simple framework for analysis of space-charge effects. Centroid and rms envelope equations including image charge effects are derived and reasonable parameter equivalences with commonly employed 2D transverse models of unbunched beams are established. This sheet beam model is then applied to analyze several problems of fundamental interest. A sheet beam thermal equilibrium distribution in a continuous focusing channel is constructed and shown to have analogous properties to two- d three-dimensional thermal equilibrium models in terms of the equilibrium structure and Deybe screening properties. The simpler formulation for sheet beams is exploited to explicitly calculate the distribution of particle oscillation frequencies within a thermal equilibrium beam. It is shown that as space-charge intensity increases, the frequency distribution becomes broad, suggesting that beams with strong space-charge can have improved stability.

  19. Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy

    DOE Patents [OSTI]

    Brennan, T.M.; Hammons, B.E.; Tsao, J.Y.

    1992-12-15

    A method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth. 3 figs.

  20. Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy

    DOE Patents [OSTI]

    Brennan, Thomas M.; Hammons, B. Eugene; Tsao, Jeffrey Y.

    1992-01-01

    A method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.

  1. Beam imaging diagnostics for heavy ion beam fusion experiments

    SciTech Connect (OSTI)

    Bieniosek, F.M.; Prost, L.; Ghiorso, W.

    2003-05-01

    We are developing techniques for imaging beams in heavy-ion beam fusion experiments in the HIF-VNL in 2 to 4 transverse dimensions. The beams in current experiments range in energy from 50 keV to 2 MeV, with beam current densities from <10 to 200 mA/cm{sup 2}, and pulse lengths of 4 to 20 {micro}s. The beam energy will range up to 10 MeV in near-future beam experiments. The imaging techniques, based on kapton films and optical scintillators, complement and, in some cases, may replace mechanical slit scanners. The kapton film images represent a time-integrated image on the film exposed to the beam. The optical scintillator utilizes glass and ceramic scintillator material imaged by a fast, image-intensified CCD-based camera. We will discuss the techniques, results, and plans for implementation of the diagnostics on the beam experiments.

  2. Roof Savings Calculator Suite

    Energy Science and Technology Software Center (OSTI)

    2013-11-22

    The software options currently supported by the simulation engine can be seen/experienced at www.roofcalc.com. It defaults all values to national averages with options to test a base-case (residential or commercial) building versus a comparison building with inputs for building type, location, building vintage, conditioned area, number of floors, and window-to-wall ratio, cooling system efficiency, type of heating, heating system efficiency, duct location, roof/ceiling insulation level, above-sheathing ventilation, radiant barrier, roof thermal mass, roof solar reflectance,more » roof thermal emittance, utility costs, roof pitch. The Roof Savings Caculator Suite adds utilities and website/web service and the integration of AtticSim with DOE-2.1E, with the end-result being Roof Savings Calculator.« less

  3. Roof Savings Calculator Suite

    SciTech Connect (OSTI)

    New, Joshua R; Garrett, Aaron; Erdem, Ender; Huang, Yu

    2013-11-22

    The software options currently supported by the simulation engine can be seen/experienced at www.roofcalc.com. It defaults all values to national averages with options to test a base-case (residential or commercial) building versus a comparison building with inputs for building type, location, building vintage, conditioned area, number of floors, and window-to-wall ratio, cooling system efficiency, type of heating, heating system efficiency, duct location, roof/ceiling insulation level, above-sheathing ventilation, radiant barrier, roof thermal mass, roof solar reflectance, roof thermal emittance, utility costs, roof pitch. The Roof Savings Caculator Suite adds utilities and website/web service and the integration of AtticSim with DOE-2.1E, with the end-result being Roof Savings Calculator.

  4. SSRL Beam Lines Map | Stanford Synchrotron Radiation Lightsource

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

    SSRL Beam Lines Map Beam Line by Number | Beam Line by Techniques | Photon Source Parameters

  5. SSRL BEAM PORT SCHEDULE

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

    ... BEAM LINE 6-2 May 24, 2004 May 25, 2004 May 26, 2004 May 27, 2004 May 28, 2004 May 29, 2004 May 30, 2004 2664 D.STRAWN 2730 A.BELL 2699 R.SHAFER 2699 R.SHAFER 2648 F.BRIDGES 2648 ...

  6. SSRL BEAM PORT SCHEDULE

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

    ... BEAM LINE 8-2 Mar. 18, 2013 Mar. 19, 2013 Mar. 20, 2013 Mar. 21, 2013 Mar. 22, 2013 Mar. 23, 2013 Mar. 24, 2013 8053 D.NORDLUND 3769 S.Dupont 3769 S.Dupont 3769 S.Dupont 3731 ...

  7. Ion-beam technologies

    SciTech Connect (OSTI)

    Fenske, G.R.

    1993-01-01

    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.

  8. SSRL BEAM PORT SCHEDULE

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

    BEAM LINE 9-1 Feb. 14, 2005 Feb. 15, 2005 Feb. 16, 2005 Feb. 17, 2005 Feb. 18, 2005 Feb. 19, 2005 Feb. 20, 2005 8803 C.SMITH 8803 C.SMITHDOWN 9B01 A.DEACON 9B01 A.DEACON 1B00 ...

  9. SSRL BEAM PORT SCHEDULE

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

    BEAM LINE 7-1 Nov. 06, 2006 Nov. 07, 2006 Nov. 08, 2006 Nov. 09, 2006 Nov. 10, 2006 Nov. 11, 2006 Nov. 12, 2006 8803 C.SMITH 8803 C.SMITH 8803 C.SMITH 8803 C.SMITH 8803 C.SMITH ...

  10. SSRL BEAM PORT SCHEDULE

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

    BEAM LINE 7-1 Nov. 11, 2013 Nov. 12, 2013 Nov. 13, 2013 Nov. 14, 2013 Nov. 15, 2013 Nov. 16, 2013 Nov. 17, 2013 8803 C.Smith 8803 C.Smith 8803 C.Smith 8803 C.Smith 8803 C.Smith ...

  11. SSRL BEAM PORT SCHEDULE

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

    BEAM LINE 9-1 Nov. 07, 2011 Nov. 08, 2011 Nov. 09, 2011 Nov. 10, 2011 Nov. 11, 2011 Nov. 12, 2011 Nov. 13, 2011 DOWN DOWN DOWN DOWN 8803 C.SMITH 8803 C.SMITH 8803 C.SMITH DOWN DOWN ...

  12. Radiative accelerations for evolutionary model calculations

    SciTech Connect (OSTI)

    Richer, J.; Michaud, G.; Rogers, F.; Iglesias, C.; Turcotte, S.; LeBlanc, F.

    1998-01-01

    Monochromatic opacities from the OPAL database have been used to calculate radiative accelerations for the 21 included chemical species. The 10{sup 4} frequencies used are sufficient to calculate the radiative accelerations of many elements for T{gt}10{sup 5}K, using frequency sampling. This temperature limit is higher for less abundant elements. As the abundances of Fe, He, or O are varied, the radiative acceleration of other elements changes, since abundant elements modify the frequency dependence of the radiative flux and the Rosseland opacity. Accurate radiative accelerations for a given element can only be obtained by allowing the abundances of the species that contribute most to the Rosseland opacity to vary during the evolution and recalculating the radiative accelerations and the Rosseland opacity during the evolution. There are physical phenomena that cannot be included in the calculations if one uses only the OPAL data. For instance, one should correct for the momentum given to the electron in a photoionization. Such effects are evaluated using atomic data from Opacity Project, and correction factors are given. {copyright} {ital 1998} {ital The American Astronomical Society}

  13. Optimizing the electron beam parameters for head-on beam-beam compensation in RHIC

    SciTech Connect (OSTI)

    Luo, Y.; Fischer, W.; Pikin, A.; Gu, X.

    2011-03-28

    Head-on beam-beam compensation is adopted to compensate the large beam-beam tune spread from the protonproton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). Two e-lenses are being built and to be in stalled near IP10 in the end of 2011. In this article we perform numeric simulation to investigate the effect of the electron beam parameters on the proton dynamics. The electron beam parameters include its transverse profile, size, current, offset and random errors in them. In this article we studied the effect of the electron beam parameters on the proton dynamics. The electron beam parameters include its transverse shape, size, current, offset and their random errors. From the study, we require that the electron beam size can not be smaller than the proton beam's. And the random noise in the electron current should be better than 0.1%. The offset of electron beam w.r.t. the proton beam center is crucial to head-on beam-beam compensation. Its random errors should be below {+-}8{micro}m.

  14. Longitudinal Space Charge Effect in Slowly Converging/Diverging Relativistic Beams

    SciTech Connect (OSTI)

    Bane, Karl LF

    2002-07-22

    Beginning with the Green function for a rod beam in a round beam pipe we derive the space charge induced average energy change and rms spread for relativistic beams that are slowly converging or diverging in round beam pipes, a result that tends to be much larger than the 1/{gamma}{sup 2} dependence for parallel beams. Our results allow for beams with longitudinal-transverse correlation, and for slow variations in beam pipe radius. We calculate, in addition, the space charge component of energy change and spread in a chicane compressor. This component indicates source regions of coherent synchrotron radiation (CSR) energy change in systems with compression. We find that this component, at the end of example compressors, approximates the total induced voltage obtained by more detailed CSR calculations. Our results depend on beam pipe radius (although only weakly) whereas CSR calculations do not normally include this parameter, suggesting that results of such calculations, for systems with beam pipes, are not complete.

  15. DRIFT ORBITS OF ENERGETIC PARTICLES IN AN INTERPLANETARY MAGNETIC FLUX ROPE

    SciTech Connect (OSTI)

    Krittinatham, W.; Ruffolo, D. E-mail: scdjr@mahidol.ac.t

    2009-10-10

    Interplanetary magnetic flux ropes have significant effects on the distribution of energetic particles in space. Flux ropes can confine solar energetic particles (SEPs) for hours, and have relatively low densities of Galactic cosmic rays (GCRs), as seen during second-stage Forbush decreases. As particle diffusion is apparently inhibited across the flux rope boundary, we suggest that guiding center drifts could play a significant role in particle motion into and out of the flux ropes. We develop an analytic model of the magnetic field in an interplanetary magnetic flux rope attached to the Sun at both ends, in quasi-toroidal coordinates, with the realistic features of a flux rope cross section that is small near the Sun, expanding with distance from the Sun, and field lines that are wound less tightly close to the Sun due to stretching by the solar wind. We calculate the particle drift velocity field due to the magnetic field curvature and gradient as a function of position and pitch-angle cosine, and trace particle guiding center orbits numerically, assuming conservation of the first adiabatic invariant. We find that SEPs in the interior of a flux rope can have drift orbits that are trapped for long times, as in a tokamak configuration, with resonant escape features as a function of the winding number. For Forbush decreases of GCRs, the drifts should contribute to a unidirectional anisotropy and net flow from one leg of the loop to the other, in a direction determined by the poloidal field direction.

  16. Neutral particle beam intensity controller

    DOE Patents [OSTI]

    Dagenhart, William K. (Oak Ridge, TN)

    1986-01-01

    A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

  17. Beam position monitor sensitivity for low-[beta] beams

    SciTech Connect (OSTI)

    Shafer, R.E. )

    1994-10-10

    Design of a beam position monitor (BPM) which is sensitive to low velo charged particle beams is considered. Quantitative estimates are made for the corrections to the conventional approximations to solutions of the Laplace Equation in two-dimensions when a BPM is used to measure to position of low velocity (low-[beta]) beams. (AIP)

  18. Formation of compressed flat electron beams with high transverse-emittance ratios

    SciTech Connect (OSTI)

    Zhu, J.; Piot, P.; Mihalcea, D.; Prokop, C. R.

    2014-08-01

    Flat beamsbeams with asymmetric transverse emittanceshave important applications in novel light-source concepts and advanced-acceleration schemes and could possibly alleviate the need for damping rings in lepton colliders. Over the last decade, a flat beam generation technique based on the conversion of an angular-momentum-dominated beam was proposed and experimentally tested. In this paper we explore the production of compressed flat beams. We especially investigate and optimize the flat beam transformation for beams with substantial fractional energy spread. We use as a simulation example the photoinjector of Fermilabs Advanced Superconducting Test Accelerator. The optimizations of the flat beam generation and compression at Advanced Superconducting Test Accelerator were done via start-to-end numerical simulations for bunch charges of 3.2 nC, 1.0 nC, and 20 pC at ?37??MeV. The optimized emittances of flat beams with different bunch charges were found to be 0.25???m (emittance ratio is ?400), 0.13????m, 15 nm before compression, and 0.41???m, 0.20???m, 16 nm after full compression, respectively, with peak currents as high as 5.5 kA for a 3.2?nC flat beam. These parameters are consistent with requirements needed to excite wakefields in asymmetric dielectric-lined waveguides or produce significant photon flux using small-gap micro-undulators.

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

    SciTech Connect (OSTI)

    Henzen, D. Manser, P.; Frei, D.; Volken, W.; Born, E. J.; Vetterli, D.; Chatelain, C.; Fix, M. K.; Neuenschwander, H.; Stampanoni, M. F. M.

    2014-02-15

    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

  20. The Beam | Open Energy Information

    Open Energy Info (EERE)

    Name: The Beam Place: Brookline, Massachusetts Zip: 2446 Product: The Beam is a start-up company that looks to establish an online retail portal that would market and sell...

  1. ANL Beams and Applications Seminar

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

    2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 Seminar Sponsers AAI ASD ATLAS HEP PHY ANL Beams and Applications Seminar The ANL Beam and Applications Seminar is...

  2. Laser beam pulse formatting method

    DOE Patents [OSTI]

    Daly, Thomas P.; Moses, Edward I.; Patterson, Ralph W.; Sawicki, Richard H.

    1994-01-01

    A method for formatting a laser beam pulse (20) using one or more delay loops (10). The delay loops (10) have a partially reflective beam splitter (12) and a plurality of highly reflective mirrors (14) arranged such that the laser beam pulse (20) enters into the delay loop (10) through the beam splitter (12) and circulates therein along a delay loop length (24) defined by the mirrors (14). As the laser beam pulse (20) circulates within the delay loop (10) a portion thereof is emitted upon each completed circuit when the laser beam pulse (20) strikes the beam splitter (12). The laser beam pulse (20) is thereby formatted into a plurality of sub-pulses (50, 52, 54 and 56). The delay loops (10) are used in combination to produce complex waveforms by combining the sub-pulses (50, 52, 54 and 56) using additive waveform synthesis.

  3. PHOTOSPHERIC FLUX CANCELLATION AND THE BUILD-UP OF SIGMOIDAL FLUX ROPES ON THE SUN

    SciTech Connect (OSTI)

    Savcheva, A. S.; Van Ballegooijen, A. A.; DeLuca, E. E.; Green, L. M.

    2012-11-10

    In this study we explore the scenario of photospheric flux cancellation being the primary formation mechanism of sigmoidal flux ropes in decaying active regions. We analyze magnetogram and X-ray observations together with data-driven non-linear force-free field (NLFFF) models of observed sigmoidal regions to test this idea. We measure the total and canceled fluxes in the regions from MDI magnetograms, as well as the axial and poloidal flux content of the modeled NLFFF flux ropes for three sigmoids-2007 February, 2007 December, and 2010 February. We infer that the sum of the poloidal and axial flux in the flux ropes for most models amounts to about 60%-70% of the canceled flux and 30%-50% of the total flux in the regions. The flux measurements and the analysis of the magnetic field structure show that the sigmoids first develop a strong axial field manifested as a sheared arcade and then, as flux cancellation proceeds, form long S-shaped field lines that contribute to the poloidal flux. In addition, the dips in the S-shaped field lines are located at the sites of flux cancellation that have been identified from the MDI magnetograms. We find that the line-of-sight-integrated free energy is also concentrated at these locations for all three regions, which can be liberated in the process of eruption. Flare-associated brightenings and flare loops coincide with the location of the X-line topology that develops at the site of most vigorous flux cancellation.

  4. ARM - PI Product - Radiative Flux Analysis

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

    ProductsRadiative Flux Analysis ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Radiative Flux Analysis 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

  5. 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.

  6. MiniBooNE Flux Data Release

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

    The Neutrino Flux Prediction at MiniBooNE", arXiv:0806.1449 [hep-ex], Phys. Rev. D. 79, 072002 (2009) The following MiniBooNE information from the large flux paper in 2009 is made available to the public: Text files containing flux information for each neutrino species Positive horn polarity (neutrino-enhanced mode) Negative horn polarity (anti neutrino-enhanced mode) Contact Information For clarifications on how to use MiniBooNE public data or for enquiries about additional data not linked

  7. Eddy Correlation Flux Measurement System (ECOR) Handbook

    SciTech Connect (OSTI)

    Cook, DR

    2011-01-31

    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.

  8. Intensity of Upward Muon Flux Due to Cosmic-Ray Neutrinos Produced in the Atmosphere

    DOE R&D Accomplishments [OSTI]

    Lee, T. D.; Robinson, H.; Schwartz, M.; Cool, R.

    1963-06-01

    Calculations were performed to determine the upward going muon flux leaving the earth's surface after production by cosmic-ray neutrinos in the crust. Only neutrinos produced in the earth's atmosphere are considered. Rates of the order of one per 100 sq m/day might be expected if an intermediate boson exists and has a mass less than 2 Bev. (auth)

  9. CLASHING BEAM PARTICLE ACCELERATOR

    DOE Patents [OSTI]

    Burleigh, R.J.

    1961-04-11

    A charged-particle accelerator of the proton synchrotron class having means for simultaneously accelerating two separate contra-rotating particle beams within a single annular magnet structure is reported. The magnet provides two concentric circular field regions of opposite magnetic polarity with one field region being of slightly less diameter than the other. The accelerator includes a deflector means straddling the two particle orbits and acting to collide the two particle beams after each has been accelerated to a desired energy. The deflector has the further property of returning particles which do not undergo collision to the regular orbits whereby the particles recirculate with the possibility of colliding upon subsequent passages through the deflector.

  10. Laser beam guard clamps

    DOE Patents [OSTI]

    Dickson, Richard K.

    2010-09-07

    A quick insert and release laser beam guard panel clamping apparatus having a base plate mountable on an optical table, a first jaw affixed to the base plate, and a spring-loaded second jaw slidably carried by the base plate to exert a clamping force. The first and second jaws each having a face acutely angled relative to the other face to form a V-shaped, open channel mouth, which enables wedge-action jaw separation by and subsequent clamping of a laser beam guard panel inserted through the open channel mouth. Preferably, the clamping apparatus also includes a support structure having an open slot aperture which is positioned over and parallel with the open channel mouth.

  11. Tetrakis-amido high flux membranes

    DOE Patents [OSTI]

    McCray, S.B.

    1989-10-24

    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.

  12. Tetrakis-amido high flux membranes

    DOE Patents [OSTI]

    McCray, Scott B. (Bend, OR)

    1989-01-01

    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.

  13. Gas Flux Sampling | Open Energy Information

    Open Energy Info (EERE)

    the true flux of hydrothermal gases may affect the results of geochemical modeling of gas dispersion in the near-surface environment.3 References 1.0 1.1 Measuring...

  14. ARM - VAP Product - lblch2flux

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

    ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send VAP Output : LBLCH2FLUX AERI, line by line...

  15. SSRL BEAM PORT SCHEDULE

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

    5-1 Oct. 30, 2006 Oct. 31, 2006 Nov. 01, 2006 Nov. 02, 2006 Nov. 03, 2006 Nov. 04, 2006 Nov. 05, 2006 DOWN Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled BEAM LINE 5-2 Oct. 30, 2006 Oct. 31, 2006 Nov. 01, 2006 Nov. 02, 2006 Nov. 03, 2006 Nov. 04, 2006 Nov. 05, 2006 DOWN Unscheduled Unscheduled Unscheduled

  16. Stationary nonlinear Airy beams

    SciTech Connect (OSTI)

    Lotti, A.; Faccio, D.; Couairon, A.; Papazoglou, D. G.; Panagiotopoulos, P.; Tzortzakis, S.; Abdollahpour, D.

    2011-08-15

    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.

  17. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, I.G.; Galvin, J.

    1987-12-22

    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.

  18. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, Ian G.; Galvin, James

    1987-01-01

    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.

  19. AmeriFlux US-Bkg Brookings

    SciTech Connect (OSTI)

    Meyers, Tilden

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Bkg Brookings. Site Description - The Brookings site is located in a private pasture, consisting of a mixture of C3 and C4 species actively used for grazing. Belonging to the Northern Great Plains Rangelands, the grassland is representative of many in the north central United States, with seasonal winter conditions and a wet growing season.

  20. Effect of Nuclear Elastic Scattering on Neutral Beam Injection Heating in Thermonuclear Plasmas

    SciTech Connect (OSTI)

    Matsuura, H.; Nakao, Y.

    2005-04-15

    An effect of the nuclear elastic scattering (NES) on the neutral beam injection (NBI) plasma heating was examined by solving the Boltzmann-Fokker-Planck (BFP) equation for beam ion in the deuterium-tritium (DT) thermonuclear plasmas. The BFP calculations show that the enhancement in the fraction of the NBI heating power deposited to ions due to NES becomes appreciable when beam energy is larger than 1MeV, and the enhancement is strongly influenced by plasma parameters.

  1. Neutral particle beam intensity controller

    SciTech Connect (OSTI)

    Dagenhart, W.K.

    1988-01-01

    A method is proposed in which an amplitude-modulated, rotating magnetic field is applied to an accelerated ion beam in a gas neutralizer to defocus the resultant neutral and ion beam in a controlled manner to control the intensity of the neutral beam along the beam axis at constant beam energy. Adjustments in the gas pressure determine the fraction of ions that is neutralized. The rotating magnetic field alters the orbits of the ions in the gas neutralizer before they are neutralized. By adjusting the gas pressure and the amplitude of the rotating magnetic field, one can control the fraction of neutral and ion particles transmitted out of the neutralizer along the central beam axis to a fusion device or other application. This method can also be used for applications where no neutralization gas is used and thus most of the beam remains in the ion state. The defocused neutral or ion particles are sprayed onto an actively cooled beam dump, which intercepts the deflected particles. The beam dump has a central opening for passage of the remaining beam along the central axis of the beam line. 4 refs., 4 figs.

  2. TH-E-BRE-06: Challenges in the Dosimetry of Flattening Filter Free Beams

    SciTech Connect (OSTI)

    Czarnecki, D; Voigts-Rhetz, P von; Zink, K

    2014-06-15

    Purpose: In current dosimetry protocols [AAPM TG51, IAEA TRS-389] the beam quality correction factor kQ and the water-to-air restricted mass collision stopping-power ratio SPR are related to beam quality specifiers %dd(10){sub x} respectively TPR{sub 20,10} Determining kQ and SPR using these regular beam quality specifiers for conventional accelerators (WFF) and flattening filter free accelerators (FFF) similarly could lead to systemic bias.The influence of the flattening filter on the relationship between various beam quality specifiers and SPR respectively k{sub Q} was studied using Monte Carlo simulations with realistic beam sources. Methods: All Monte Carlo simulations were performed using the BEAMnrc/EGSnrc code system. Radiation transport through nine linear accelerator heads modeled according to technical drawings given by the manufactures and a {sup 60} Co therapy source was simulated with BEAMnrc and then used as a radiation source for further simulations. FFF beam sources were implemented by removing the fattening filter from the WFF model. SPR was calculated applying the user code SPRRZnrc. The mean photon energy below the accelerator head and the mean energies of photons and electrons at the measuring point within the water phantom were calculated using FLURZnrc. Dose calculations within a small water voxel and the thimble ionization chamber PTW-31010 in a water depth of 10 cm were made using the egs-chamber code. Results: SPR and k{sub Q} as a function of fluence spectra based beam quality specifiers as well as conventional beam quality specifiers differ systematically between FFF and WFF beams. According to the results the specifier %dd(10){sub x} revealed the smallest deviation (max. 0.4%) between FFF and WFF beams. Conclusion: The results show that %dd(10){sub x} is an acceptable beam quality specifier for FFF beams. Nevertheless the results confirm the expected bias between FFF and WFF beams which must by further investigated.

  3. How Are Momentum Savings Calculated?

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

    Simplifying the Math: How Are Momentum Savings Calculated? Many people have heard about Momentum savings but don't understand how these types of savings are calculated. The short...

  4. Fluorescence-based video profile beam diagnostics: Theory and experience

    SciTech Connect (OSTI)

    Sandoval, D.; Gilpatrick, D.; Shinas, M.; Garcia, R.; Yuan, V.; Zander, M.

    1994-05-01

    Inelastic collisions between accelerated particles and residual gas in the accelerator vessel can cause the residual gas to fluoresce. The gas fluorescence intensity is proportional to the current density of the particle beam. This process provides the foundation for a video diagnostic system to measure the profile and position of accelerated particle beams. This, in fact, has proven to be a useful diagnostic at several installations. This paper describes the light production process resulting from beam -- residual gas interactions and gives formulas for estimating the beam radiance for various conditions. Ground Test Accelerator (GTA) radiance calculations will be used as an example. In addition, measurement experiences with the GTA video diagnostics system will be discussed.

  5. Fluorescence-based video profile beam diagnostics: Theory and experience

    SciTech Connect (OSTI)

    Sandoval, D.P.; Garcia, R.C.; Gilpatrick, J.D.; Shinas, M.A.; Wright, R.; Yuan, V.; Zander, M.E. )

    1994-10-10

    Inelastic collisions between accelerated particles and residual gas in the accelerator vessel can cause the residual gas to fluoresce. The gas fluorescence intensity is proportional to the current density of the particle beam. This process provides the foundation for a video diagnostics system to measure the profile and position of accelerated particle beams. This, in fact, has proven to be a useful diagnostic at several installations. This paper describes the light production process resulting from beam-residual gas interactions and gives formulas for estimating the beam radiance for various conditions. Ground Test Accelerator (GTA) radiance calculations will be used as an example. In addition, measurement experiences with the GTA video diagnostics system will be discussed.

  6. First Beam Measurements with the LHC Synchrotron Light Monitors

    SciTech Connect (OSTI)

    Lefevre, Thibaut; Bravin, Enrico; Burtin, Gerard; Guerrero, Ana; Jeff, Adam; Rabiller, Aurelie; Roncarolo, Federico; Fisher, Alan; /SLAC

    2012-07-13

    The continuous monitoring of the transverse sizes of the beams in the Large Hadron Collider (LHC) relies on the use of synchrotron radiation and intensified video cameras. Depending on the beam energy, different synchrotron light sources must be used. A dedicated superconducting undulator has been built for low beam energies (450 GeV to 1.5 TeV), while edge and centre radiation from a beam-separation dipole magnet are used respectively for intermediate and high energies (up to 7 TeV). The emitted visible photons are collected using a retractable mirror, which sends the light into an optical system adapted for acquisition using intensified CCD cameras. This paper presents the design of the imaging system, and compares the expected light intensity with measurements and the calculated spatial resolution with a cross calibration performed with the wire scanners. Upgrades and future plans are also discussed.

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

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

    Shin, Young-Min

    2014-09-15

    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)morefrom 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

  8. SciDAC Advances and Applications in Computational Beam Dynamics

    SciTech Connect (OSTI)

    Ryne, R.; Abell, D.; Adelmann, A.; Amundson, J.; Bohn, C.; Cary, J.; Colella, P.; Dechow, D.; Decyk, V.; Dragt, A.; Gerber, R.; Habib, S.; Higdon, D.; Katsouleas, T.; Ma, K.-L.; McCorquodale, P.; Mihalcea, D.; Mitchell, C.; Mori, W.; Mottershead, C.T.; Neri, F.; Pogorelov, I.; Qiang, J.; Samulyak, R.; Serafini, D.; Shalf, J.; Siegerist, C.; Spentzouris, P.; Stoltz, P.; Terzic, B.; Venturini, M.; Walstrom, P.

    2005-06-26

    SciDAC has had a major impact on computational beam dynamics and the design of particle accelerators. Particle accelerators--which account for half of the facilities in the DOE Office of Science Facilities for the Future of Science 20 Year Outlook--are crucial for US scientific, industrial, and economic competitiveness. Thanks to SciDAC, accelerator design calculations that were once thought impossible are now carried routinely, and new challenging and important calculations are within reach. SciDAC accelerator modeling codes are being used to get the most science out of existing facilities, to produce optimal designs for future facilities, and to explore advanced accelerator concepts that may hold the key to qualitatively new ways of accelerating charged particle beams. In this poster we present highlights from the SciDAC Accelerator Science and Technology (AST) project Beam Dynamics focus area in regard to algorithm development, software development, and applications.

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

    SciTech Connect (OSTI)

    Valerio-Lizarraga, Cristhian A.; Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard; Leon-Monzon, Ildefonso; Midttun, ystein; University of Oslo, Oslo

    2014-02-15

    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.

  10. Target and orbit feedback simulations of a muSR beam line at BNL

    SciTech Connect (OSTI)

    MacKay, W.; Blaskiewicz, M.; Fischer, W.; Pile, P.

    2015-07-28

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. For a dc beam an ideal µSR flux for surface µ+ should be about 40 kHz/mm2. In this report we show how this flux could be achieved in a beam line using the AGS complex at BNL for a source of protons. We also determined that an orbit feedback system with a pair of thin silicon position monitors and kickers would miss the desired flux by at least an order of magnitude, even with perfect time resolution and no multiple scattering.

  11. BATMAN beam properties characterization by the beam emission spectroscopy diagnostic

    SciTech Connect (OSTI)

    Bonomo, F.; Ruf, B.; Schiesko, L.; Fantz, U.; Franzen, P.; Riedl, R.; Wünderlich, D.; Barbisan, M.; Pasqualotto, R.; Serianni, G.; Cristofaro, S.

    2015-04-08

    The ITER neutral beam heating systems are based on the production and acceleration of negative ions (H/D) up to 1 MV. The requirements for the beam properties are strict: a low core beam divergence (< 0.4 °) together with a low source pressure (≤ 0.3 Pa) would permit to reduce the ion losses along the beamline, keeping the stripping particle losses below 30%. However, the attainment of such beam properties is not straightforward. At IPP, the negative ion source testbed BATMAN (BAvarian Test MAchine for Negative ions) allows for deepening the knowledge of the determination of the beam properties. One of the diagnostics routinely used to this purpose is the Beam Emission Spectroscopy (BES): the H{sub α} light emitted in the beam is detected and the corresponding spectra are evaluated to estimate the beam divergence and the stripping losses. The BES number of lines of sight in BATMAN has been recently increased: five horizontal lines of sight providing a vertical profile of the beam permit to characterize the negative ion beam properties in relation to the source parameters. Different methods of H{sub α} spectra analysis are here taken into account and compared for the estimation of the beam divergence and the amount of stripping. In particular, to thoroughly study the effect of the space charge compensation on the beam divergence, an additional hydrogen injection line has been added in the tank, which allows for setting different background pressure values (one order of magnitude, from about 0.04 Pa up to the source pressure) in the beam drift region.

  12. TRACKING CODE DEVELOPMENT FOR BEAM DYNAMICS OPTIMIZATION

    SciTech Connect (OSTI)

    Yang, L.

    2011-03-28

    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. Intense Ion Beam for Warm Dense Matter Physics

    SciTech Connect (OSTI)

    Coleman, Joshua Eugene

    2008-05-23

    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

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

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

    More Documents & Publications Integration of Novel Flux Coupling Motor and Current Source Inverter Novel Flux Coupling Machine without Permanent Magnets John Hsu, Oak Ridge ...

  15. Gas Flux Sampling At Long Valley Caldera Geothermal Area (Lewicki...

    Open Energy Info (EERE)

    between chamber CO2 fluxes and the atmospheric parameters over a comparable time period. Energy balance closure was assessed by statistical regression of EC energy fluxes...

  16. Production of intense beams of singly charged radioactive ions

    SciTech Connect (OSTI)

    Kuznetsov, G.; Batazova, M.; Gubin, K.; Logachev, P.; Martyshkin, P.

    2006-03-15

    An apparatus for the production of intense beams of singly charged radioactive ions operating in on-line regime is proposed. The radioactive atoms are produced in a uranium-graphite (UC) target bombarded with neutrons. The neutron flux is generated by a graphite neutron converter, which is bombarded with protons. The atoms of the produced isotopes are ionized in the electron beam generated with the electron gun and the ions of interest are extracted in a separator. The apparatus consists of the following parts. (1) Rotating converter dissipating a substantial power of proton beam. (2) UC target placed in a graphite container at high temperature. The atoms of radioactive isotopes can be extracted with a flow of noble gas. (3) Triode electron gun with ionization channel is placed inside the solenoid forming a focusing magnetic field. The cathode of the electron gun is a spout of the graphite container. The atoms of radioactive isotopes are carried with gas flow through the spout into the electron beam. (4) Correction coil located near the gun matches the electron beam with the ionization channel. (5) The first anode has a potential of 1-4 kV with respect to the cathode, and the second anode has some lower potential than the first anode and it is the tube of ionization channel. (6) Electron collector dissipates the electron-beam power. (7) Uranium-graphite target, the gun, the ionization channel as well as solenoid are located on an isolated platform with potential of 30-60 kV with respect to ground. The beam of singly charged ions from the ionization channel passes the collector, goes through the extractor, acquires energy of 30-60 keV, and gets transported to the separator where the required species are selected.

  17. Control of post-disruption runaway electron beams in DIII-D

    SciTech Connect (OSTI)

    Eidietis, N. W.; Humphreys, D. A.; Strait, E. J.; VanZeeland, M. A.; Wesley, J. C.; Commaux, N.; Jernigan, T. C.; Hollmann, E. M.; Moyer, R. A.; Yu, J. H.

    2012-05-15

    Recent experiments in the DIII-D tokamak have demonstrated real-time control and dissipation of post-disruption runaway electron (RE) beams. In the event that disruption avoidance, control, and mitigation schemes fail to avoid or suppress RE generation, active control of the RE beam may be an important line of defense to prevent the rapid, localized deposition of RE beam energy onto vulnerable vessel sections. During and immediately after the current quench, excessive radial compression of the runaway beams is avoided by a combination of techniques, improving the likelihood of the beams surviving this dynamic period without a fast termination. Once stabilized, the runaway beams are held in a steady state (out to the ohmic flux limit) with the application of active plasma current and position controls. Beam interaction with the vessel wall is minimized by avoiding distinct thresholds for enhanced wall interaction at small and large radii, corresponding to inner wall and outer limiter interaction, respectively. Staying within the 'safe zone' between those radial thresholds allows for the sustainment of long-lived, quiescent runaway beams. The total beam energy and runaway electron population are then dissipated gradually by a controlled ramp-down of the runaway current.

  18. Sensitivity analysis of coupled criticality calculations

    SciTech Connect (OSTI)

    Perko, Z.; Kloosterman, J. L.; Lathouwers, D.

    2012-07-01

    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)

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

    SciTech Connect (OSTI)

    Lasche, G.P.

    1988-04-05

    A method for recovering energy in an inertial confinement fusion reactor having a reactor chamber and a sphere forming means positioned above an opening in the reactor chamber is described, comprising: embedding a fusion target fuel capsule having a predetermined yield in the center of a hollow solid lithium tube and subsequently embedding the hollow solid lithium tube in a liquid lithium medium; using the sphere forming means for forming the liquid lithium into a spherical shaped liquid lithium mass having a diameter smaller than the length of the hollow solid lithium tube with the hollow solid lithium tube being positioned along a diameter of the spherical shaped mass, providing the spherical shaped liquid lithium mass with the fusion fuel target capsule and hollow solid lithium tube therein as a freestanding liquid lithium shaped spherical shaped mass without any external means for maintaining the spherical shape by dropping the liquid lithium spherical shaped mass from the sphere forming means into the reactor chamber; producing a magnetic field in the reactor chamber; imploding the target capsule in the reactor chamber to produce fusion energy; absorbing fusion energy in the liquid lithium spherical shaped mass to convert substantially all the fusion energy to shock induced kinetic energy of the liquid lithium spherical shaped mass which expands the liquid lithium spherical shaped mass; and compressing the magnetic field by expansion of the liquid lithium spherical shaped mass and recovering useful energy.

  20. GENERATION OF MAGNETOHYDRODYNAMIC WAVES IN LOW SOLAR ATMOSPHERIC FLUX TUBES BY PHOTOSPHERIC MOTIONS

    SciTech Connect (OSTI)

    Mumford, S. J.; Fedun, V.; Erdlyi, R.

    2015-01-20

    Recent ground- and space-based observations reveal the presence of small-scale motions between convection cells in the solar photosphere. In these regions, small-scale magnetic flux tubes are generated via the interaction of granulation motion and the background magnetic field. This paper studies the effects of these motions on magnetohydrodynamic (MHD) wave excitation from broadband photospheric drivers. Numerical experiments of linear MHD wave propagation in a magnetic flux tube embedded in a realistic gravitationally stratified solar atmosphere between the photosphere and the low choromosphere (above ? = 1) are performed. Horizontal and vertical velocity field drivers mimic granular buffeting and solar global oscillations. A uniform torsional driver as well as Archimedean and logarithmic spiral drivers mimic observed torsional motions in the solar photosphere. The results are analyzed using a novel method for extracting the parallel, perpendicular, and azimuthal components of the perturbations, which caters to both the linear and non-linear cases. Employing this method yields the identification of the wave modes excited in the numerical simulations and enables a comparison of excited modes via velocity perturbations and wave energy flux. The wave energy flux distribution is calculated to enable the quantification of the relative strengths of excited modes. The torsional drivers primarily excite Alfvn modes (?60% of the total flux) with small contributions from the slow kink mode, and, for the logarithmic spiral driver, small amounts of slow sausage mode. The horizontal and vertical drivers primarily excite slow kink or fast sausage modes, respectively, with small variations dependent upon flux surface radius.

  1. Benthic fluxes and pore water studies from sediments of the central equatorial north Pacific: Nutrient diagenesis

    SciTech Connect (OSTI)

    Berelson, W.M.; Hammond, D.E.; Xu, X. ); O'Neill, D. Dames and Moore, Los Angeles, CA ); Chin, C. Moss Landing Marine Lab., CA ); Zukin, J. Dames and Moore, Goleta, CA )

    1990-11-01

    Benthic exchange rates of radon-222, oxygen, nitrate, ammonia, and silica were determined using an in situ benthic flux chamber and by modeling pore water profiles at three sites in the central equatorial north Pacific. A comparison of these results reveals several artifacts of pore water collection and processing. Whole-core squeezer (WCS) silica profiles are influenced by adsorption during squeezing and yield calculated fluxes that are too large. Pore water ammonia profiles show near-surface maxima that appear to be an artifact of core recovery. Near-surface nitrate measurements may also be suspect due to oxidation of the ammonia released, causing anomalously large nitrate gradients that yield over-estimates of benthic exchange rates. Fluxes of radon, oxygen, and nitrate calculated from WCS profiles agree with chamber fluxes to better than 40% at all sites. Fluxes of silica and nitrate calculated from pore water data collected at coarser scales (> 1 cm intervals) agree within 50% with chamber measurements. previous flux estimates from pore water and solid phase models established at two of these sites using data collected 6 years prior to this work differ from these chamber measurements, in some cases by up to a factor of 5 due to modeling uncertainties and temporal variabilities in the delivery of organic matter to a site. The benthic oxygen consumption rates measured at these sites are similar (they average 0.36 {plus minus} 0.03 mmol m{sup {minus}2} day{sup {minus}1}) and are consistent with a trend of oxygen uptake vs. water depth previously established by others on a transect through the oligotrophic north Pacific gyre.

  2. RECENT EXPERIENCE WITH ELECTRON LENS BEAM-BEAM COMPENSATION AT...

    Office of Scientific and Technical Information (OSTI)

    with use of bent crystals and pulsed dipole deflectors (orbit correctors). The angular beam deflection by the crystal - see Fig.2 - must be large enough to send the...

  3. Target design optimization for an electron accelerator driven subcritical facility with circular and square beam profiles.

    SciTech Connect (OSTI)

    Gohar, M. Y. A; Sofu, T.; Zhong, Z.; Belch, H.; Naberezhnev, D.; Nuclear Engineering Division

    2008-10-30

    and uranium are very similar allowing the use of either material in the subcritical assembly without changing its characteristics. However, the uranium target has a higher neutron yield, which increases the neutron flux of the subcritical assembly. Based on the considered dimensions and heat generation profiles, the commercial CFD software Star-CD is used for the thermal-hydraulic analysis of each target design to satisfy a set of thermal criteria, the most limiting of which being to maintain the water temperature 50 below the boiling point. It is found that the turbulence in the inlet channels dissipates quickly in narrow gaps between the target plates and, as a result, the heat transfer is limited by the laminar flow conditions. On average, 3-D CFD analyses of target assemblies agree well with 1-D calculations using RELAP (performed by KIPT). However, the recirculation and stagnation zones predicted with the CFD models prove the importance of a 3-D analysis to avoid the resulting hotspots. The calculated temperatures are subsequently used for the structural analysis of each target configuration to satisfy the other engineering design requirements. The thermo-structural calculations are performed mostly with NASTRAN and the results occasionally compared with the results from MARC. Both, NASTRAN and MARC are commercially available structural-mechanics analysis software. Although, a significant thermal gradient forms in target elements along the beam direction, the high thermal stresses are generally observed peripherally around the edge of thin target disks/plates. Due to its high thermal conductivity, temperatures and thermal stresses in tungsten target are estimated to be significantly lower than in uranium target. The deformations of the target disks/plates are found to be insignificant, which eliminate concerns for flow blockages in narrow coolant channels. Consistent with the specifications of the KIPT accelerator to be used in this facility, the electron beam

  4. A scintillating fission detector for neutron flux measurements

    SciTech Connect (OSTI)

    Stange, Sy; Esch, Ernst I; Burgett, Eric A; May, Iain; Muenchausen, Ross E; Taw, Felicia; Tovesson, Fredrik K

    2010-01-01

    Neutron flux monitors are commonly used for a variety of nuclear physics applications. A scintillating neutron detector, consisting of a liquid scintillator loaded with fissionable material, has been developed, characterized, and tested in the beam line at the Los Alamos Neutron Science Center, and shows a significant improvement in neutron sensitivity compared with a conventional fission chamber. Recent research on nanocomposite-based scintillators for gamma-ray detection indicates that this approach can be extended to load nanoparticles of fissionable material into a scintillating matrix, with up to three orders of magnitude higher loading than typical fission chambers. This will result in a rugged, cost-efficient detector with high efficiency, a short signal rise time, and the ability to be used in low neutron-flux environments. Initial efforts to utilize the luminescence of uranyl oxide to eliminate the need for wavelength-shifting dyes were unsuccessful. Excitation of uranyl compounds has been reported at wavelengths ranging from 266 nm to 532 nm. However, neither the 300 nm emission of toluene, nor the 350 nm emission of PPO, nor the 410 nm emission of POPOP resulted in significant excitation of and emission by uranyl oxide. As indicated by UV/visible spectroscopy, light emitted at these wavelengths was absorbed by the colored solution. {sup 235}U remains the most attractive candidate for a fissionable scintillator, due to its high fission cross-section and lack of a threshold fission energy, but all solutions containing molecular uranium compounds will be colored, most more highly than the U{sup 6+} compounds used here. Research is therefore continuing toward the fabrication of uranium nanoparticles, in which, due to Rayleigh scattering, the coloration should be less pronounced. The characterization of the thorium-loaded liquid scintillator and the fabrication of the 100 mL detectors for use at LANSCE demonstrated the feasibility of loading fissionable

  5. LANSCE Beam Current Limiter (XL)

    SciTech Connect (OSTI)

    Gallegos, F.R.; Hall, M.J.

    1997-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) is an engineered safety system that provides personnel protection from prompt radiation due to accelerated proton beams. The Beam Current Limiter (XL), as an active component of the RSS, limits the maximum average current in a beamline, thus the current available for a beam spill accident. Exceeding the pre-set limit initiates action by the RSS to mitigate the hazard (insertion of beam stoppers in the low energy beam transport). The beam limiter is an electrically isolated, toroidal transformer and associated electronics. The device was designed to continuously monitor beamline currents independent of any external timing. Fail-safe operation was a prime consideration in its development. Fail-safe operation is defined as functioning as intended (due to redundant circuitry), functioning with a more sensitive fault threshold, or generating a fault condition. This report describes the design philosophy, hardware, implementation, operation, and limitations of the device.

  6. Neutrino Fluxes from NUHM LSP Annihilations in the Sun

    SciTech Connect (OSTI)

    Olive, Keith

    2011-08-12

    We extend our previous studies of the neutrino fluxes expected from neutralino LSP annihilations inside the Sun to include variants of the minimal supersymmetric extension of the Standard Model (MSSM) with squark, slepton and gaugino masses constrained to be universal at the GUT scale, but allowing one or two non-universal supersymmetry-breaking parameters contributing to the Higgs masses (NUHM1,2). As in the constrained MSSM (CMSSM) with universal Higgs masses, there are large regions of the NUHM parameter space where the LSP density inside the Sun is not in equilibrium, so that the annihilation rate may be far below the capture rate, and there are also large regions where the capture rate is not dominated by spin-dependent LSP-proton scattering. The spectra possible in the NUHM are qualitatively similar to those in the CMSSM. We calculate neutrino-induced muon fluxes above a threshold energy of 10 GeV, appropriate for the IceCube/DeepCore detector, for points where the NUHM yields the correct cosmological relic density for representative choices of the NUHM parameters. We find that the IceCube/DeepCore detector can probe regions of the NUHM parameter space in addition to analogues of the focus-point strip and the tip of the coannihilation strip familiar from the CMSSM. These include regions with enhanced Higgsino-gaugino mixing in the LSP composition, that occurs where neutralino mass eigenstates cross over. On the other hand, rapid-annihilation funnel regions in general yield neutrino fluxes that are unobservably small.

  7. Simulation of beam-induced plasma for the mitigation of beam-beam effects

    SciTech Connect (OSTI)

    Ma, J.; Wang, G.; Samulyak, R.; Yu, K.; Litvinenko, V.

    2015-05-03

    One of the main challenges in the increase of luminosity of circular colliders is the control of the beam-beam effect. In the process of exploring beam-beam mitigation methods using plasma, we evaluated the possibility of plasma generation via ionization of neutral gas by proton beams, and performed highly resolved simulations of the beam-plasma interaction using SPACE, a 3D electromagnetic particle-in-cell code. The process of plasma generation is modelled using experimentally measured cross-section coefficients and a plasma recombination model that takes into account the presence of neutral gas and beam-induced electromagnetic fields. Numerically simulated plasma oscillations are consistent with theoretical analysis. In the beam-plasma interaction process, high-density neutral gas reduces the mean free path of plasma electrons and their acceleration. A numerical model for the drift speed as a limit of plasma electron velocity was developed. Simulations demonstrate a significant reduction of the beam electric field in the presence of plasma. Preliminary simulations using fully-ionized plasma have also been performed and compared with the case of beam-induced plasma.

  8. Beam experiments related to the head-on beam-beam compensation project at RHIC

    SciTech Connect (OSTI)

    Montag, C.; Bai, M.; Drees, A.; Fischer, W.; Marusic, A.; Wang, G.

    2011-03-28

    Beam experiments have been performed in RHIC to determine some key parameters of the RHIC electron lenses, and to test the capability of verifying lattice modifications by beam measurements. We report the status and recent results of these experiments. The Relativistic Heavy Ion Collider (RHIC) consists of two superconducting storage rings that intersect at six locations around its circumference. Beams collide in interaction points (IPs) 6 and 8, which are equipped with the detectors STAR and PHENIX, respectively (Fig. 1). With the polarized proton working point constrained between 2/3 and 7/10 to achieve good luminosity lifetime and maintain polarization, the proton bunch intensity is limited to 2 {center_dot} 10{sup 11} protons per bunch by the resulting beam-beam tuneshift. To overcome this limitation, installation of an electron lens in IP 10 is foreseen to partially compensate the beam-beam effect and reduce the beam-beam tuneshift parameter. As part of this project, beam experiments are being performed at RHIC to determine key parameters of the electron lens as well as to verify lattice modifications.

  9. Magnetically operated beam dump for dumping high power beams in a neutral beamline

    DOE Patents [OSTI]

    Dagenhart, W.K.

    1984-01-27

    It is an object of this invention to provide a beam dump system for a neutral beam generator which lowers the time-averaged power density of the beam dump impingement surface. Another object of this invention is to provide a beam dump system for a neutral particle beam based on reionization and subsequent magnetic beam position modulation of the beam onto a beam dump surface to lower the time-averaged power density of the beam dump ion impingement surface.

  10. Real Time Flux Control in PM Motors

    SciTech Connect (OSTI)

    Otaduy, P.J.

    2005-09-27

    Significant research at the Oak Ridge National Laboratory (ORNL) Power Electronics and Electric Machinery Research Center (PEEMRC) is being conducted to develop ways to increase (1) torque, (2) speed range, and (3) efficiency of traction electric motors for hybrid electric vehicles (HEV) within existing current and voltage bounds. Current is limited by the inverter semiconductor devices' capability and voltage is limited by the stator wire insulation's ability to withstand the maximum back-electromotive force (emf), which occurs at the upper end of the speed range. One research track has been to explore ways to control the path and magnitude of magnetic flux while the motor is operating. The phrase, real time flux control (RTFC), refers to this mode of operation in which system parameters are changed while the motor is operating to improve its performance and speed range. RTFC has potential to meet an increased torque demand by introducing additional flux through the main air gap from an external source. It can augment the speed range by diverting flux away from the main air gap to reduce back-emf at high speeds. Conventional RTFC technology is known as vector control [1]. Vector control decomposes the stator current into two components; one that produces torque and a second that opposes (weakens) the magnetic field generated by the rotor, thereby requiring more overall stator current and reducing the efficiency. Efficiency can be improved by selecting a RTFC method that reduces the back-emf without increasing the average current. This favors methods that use pulse currents or very low currents to achieve field weakening. Foremost in ORNL's effort to develop flux control is the work of J. S. Hsu. Early research [2,3] introduced direct control of air-gap flux in permanent magnet (PM) machines and demonstrated it with a flux-controlled generator. The configuration eliminates the problem of demagnetization because it diverts all the flux from the magnets instead of

  11. Neutron Beam Effects on Spin-Exchange-Polarized 3He

    SciTech Connect (OSTI)

    Sharma, M.; Babcock, E.; Anderson, K. H.; Barron-Palos, L.; Becker, M.; Boag, S.; Chen, W. C.; Chupp, T. E.; Danagoulian, A.; Gentile, T. R.; Klein, A.; Penttila, S.; Petoukhov, A.; Soldner, T.; Tardiff, E. R.; Walker, T. G.; Wilburn, W. S.

    2008-08-01

    We have observed depolarization effects when high intensity cold neutron beams are incident on alkali-metal spin-exchange-polarized {sup 3}He cells used as neutron spin filters. This was first observed as a reduction of the maximum attainable {sup 3}He polarization and was attributed to a decrease of alkali-metal polarization, which led us to directly measure alkali-metal polarization and spin relaxation over a range of neutron fluxes at Los Alamos Neutron Science Center and Institute Laue-Langevin. The data reveal a new alkali-metal spin-relaxation mechanism that approximately scales as {radical}{phi}{sub n}, where {phi}{sub n} is the neutron capture-flux density incident on the cell. This is consistent with an effect proportional to the concentration of electron-ion pairs but is much larger than expected from earlier work.

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

    SciTech Connect (OSTI)

    Gerbaldo, Roberto; Ghigo, Gianluca; Gozzelino, Laura; Laviano, Francesco; Amato, Antonino; Rovelli, Alberto; Cherubini, Roberto

    2013-07-18

    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.

  13. CURRENT BUILDUP IN EMERGING SERPENTINE FLUX TUBES

    SciTech Connect (OSTI)

    Pariat, E.; Masson, S.; Aulanier, G.

    2009-08-20

    The increase of magnetic flux in the solar atmosphere during active-region formation involves the transport of the magnetic field from the solar convection zone through the lowest layers of the solar atmosphere, through which the plasma {beta} changes from >1 to <1 with altitude. The crossing of this magnetic transition zone requires the magnetic field to adopt a serpentine shape also known as the sea-serpent topology. In the frame of the resistive flux-emergence model, the rising of the magnetic flux is believed to be dynamically driven by a succession of magnetic reconnections which are commonly observed in emerging flux regions as Ellerman bombs. Using a data-driven, three-dimensional (3D) magnetohydrodynamic numerical simulation of flux emergence occurring in active region 10191 on 2002 November 16-17, we study the development of 3D electric current sheets. We show that these currents buildup along the 3D serpentine magnetic-field structure as a result of photospheric diverging horizontal line-tied motions that emulate the observed photospheric evolution. We observe that reconnection can not only develop following a pinching evolution of the serpentine field line, as usually assumed in two-dimensional geometry, but can also result from 3D shearing deformation of the magnetic structure. In addition, we report for the first time on the observation in the UV domain with the Transition Region and Coronal Explorer (TRACE) of extremely transient loop-like features, appearing within the emerging flux domain, which link several Ellermam bombs with one another. We argue that these loop transients can be explained as a consequence of the currents that build up along the serpentine magnetic field.

  14. Eddy Correlation Flux Measurement System Handbook

    SciTech Connect (OSTI)

    Cook, D. R.

    2016-01-01

    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. The instruments used are: • a fast-response, three-dimensional (3D) wind sensor (sonic anemometer) to obtain the orthogonal wind components and the speed of sound (SOS) (used to derive the air temperature) • an open-path infrared gas analyzer (IRGA) to obtain the water vapor density and the CO2 concentration, and • an open-path infrared gas analyzer (IRGA) to obtain methane density and methane flux at one SGP EF and at the NSA CF. The ECOR systems are deployed at the locations where other methods for surface flux measurements (e.g., energy balance Bowen ratio [EBBR] systems) are difficult to employ, primarily at the north edge of a field of crops. A Surface Energy Balance System (SEBS) has been installed collocated with each deployed ECOR system in SGP, NSA, Tropical Western Pacific (TWP), ARM Mobile Facility 1 (AMF1), and ARM Mobile Facility 2 (AMF2). The surface energy balance system consists of upwelling and downwelling solar and infrared radiometers within one net radiometer, a wetness sensor, and soil measurements. The SEBS measurements allow the comparison of ECOR sensible and latent heat fluxes with the energy balance determined from the SEBS and provide information on wetting of the sensors for data quality purposes. The SEBS at one SGP and one NSA site also support upwelling and downwelling PAR measurements to qualify those two locations as Ameriflux sites.

  15. Equilibrium calculations of firework mixtures

    SciTech Connect (OSTI)

    Hobbs, M.L.; Tanaka, Katsumi; Iida, Mitsuaki; Matsunaga, Takehiro

    1994-12-31

    Thermochemical equilibrium calculations have been used to calculate detonation conditions for typical firework components including three report charges, two display charges, and black powder which is used as a fuse or launch charge. Calculations were performed with a modified version of the TIGER code which allows calculations with 900 gaseous and 600 condensed product species at high pressure. The detonation calculations presented in this paper are thought to be the first report on the theoretical study of firework detonation. Measured velocities for two report charges are available and compare favorably to predicted detonation velocities. However, the measured velocities may not be true detonation velocities. Fast deflagration rather than an ideal detonation occurs when reactants contain significant amounts of slow reacting constituents such as aluminum or titanium. Despite such uncertainties in reacting pyrotechnics, the detonation calculations do show the complex nature of condensed phase formation at elevated pressures and give an upper bound for measured velocities.

  16. Broad-band beam buncher

    DOE Patents [OSTI]

    Goldberg, David A.; Flood, William S.; Arthur, Allan A.; Voelker, Ferdinand

    1986-01-01

    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.

  17. Compact electron beam focusing column

    SciTech Connect (OSTI)

    Persaud, Arun; Leung, Ka-Ngo; Reijonen, Jani

    2001-07-13

    A novel design for an electron beam focusing column has been developed at LBNL. The design is based on a low-energy spread multicusp plasma source which is used as a cathode for electron beam production. The focusing column is 10 mm in length. The electron beam is focused by means of electrostatic fields. The column is designed for a maximum voltage of 50 kV. Simulations of the electron trajectories have been performed by using the 2-D simulation code IGUN and EGUN. The electron temperature has also been incorporated into the simulations. The electron beam simulations, column design and fabrication will be discussed in this presentation.

  18. ARM - Field Campaign - ISDAC - Hemispheric Flux Spectroradiometer

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

    - Hemispheric Flux Spectroradiometer ARM Data Discovery Browse Data Related Campaigns Indirect and Semi-Direct Aerosol Campaign (ISDAC) 2008.04.01, Ghan, AAF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : ISDAC - Hemispheric Flux Spectroradiometer 2008.03.31 - 2008.05.31 Lead Scientist : Dan Lubin For data sets, see below. Abstract In connection with ISDAC, this campaign further investigated the role of aerosol physics and chemistry

  19. Dual neutron flux/temperature measurement sensor

    DOE Patents [OSTI]

    Mihalczo, John T.; Simpson, Marc L.; McElhaney, Stephanie A.

    1994-01-01

    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.

  20. Dual neutron flux/temperature measurement sensor

    DOE Patents [OSTI]

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

    1994-10-04

    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.

  1. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, Fulvio; Cohen, Samuel A.; Bennett, Timothy; Timberlake, John R.

    1993-01-01

    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.

  2. AmeriFlux US-Akn Aiken

    SciTech Connect (OSTI)

    Leclerc, Monique

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Akn Aiken. Site Description - The Aiken site is located within the Atlantic Coastal Plain Providence on a U.S. Department of Energy reservation (806 sq km) at Savannah River National Laboratory. Areas of the site not used for industrial purposes were planted with forests starting in the early 1950s, including the site of the Aiken tower. The site measurements are representative of the southeastern US within a mixed agricultural, residential, and industrial zone.

  3. Effect of the electron lenses on the RHIC proton beam closed orbit

    SciTech Connect (OSTI)

    Gu, X.; Luo, Y.; Pikin, A.; Okamura, M.; Fischer, W.; Montag, C.; Gupta, R.; Hock, J.; Jain, A.; Raparia, D.

    2011-02-01

    We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed at RHIC IR10. The transverse fields of the E-lenses bending solenoids and the fringe field of the main solenoids will shift the proton beam. We calculate the transverse kicks that the proton beam receives in the electron lens via Opera. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.

  4. AmeriFlux US-Los Lost Creek

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

    Desai, Ankur [University of Wisconsin

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Los Lost Creek. Site Description - Shrub wetland site, chosen to be representative of the wetlands within the WLEF tall tower flux footprint. This is a deciduous shrub wetland. Coniferous and grassy stands also exist within the WLEF flux footprint. Solar power. The site has excellent micrometeorological characteristics.

  5. Compact steady-state and high-flux Falcon ion source for tests of plasma-facing materials

    SciTech Connect (OSTI)

    Girka, O.; Bizyukov, I.; Sereda, K.; Bizyukov, A.; Gutkin, M.; Sleptsov, V.

    2012-08-15

    This paper describes the design and operation of the Falcon ion source. It is based on conventional design of anode layer thrusters. This ion source is a versatile, compact, affordable, and highly functional in the research field of the fusion materials. The reversed magnetic field configuration of the source allows precise focusing of the ion beam into small spot of Almost-Equal-To 3 mm and also provides the limited capabilities for impurity mass-separation. As the result, the source generates steady-state ion beam, which irradiates surface with high heat (0.3 - 21 MW m{sup -2}) and particle fluxes (4 Multiplication-Sign 10{sup 21}- 3 Multiplication-Sign 10{sup 23} m{sup -2}s{sup -1}), which approaches the upper limit for the flux range expected in ITER.

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

    SciTech Connect (OSTI)

    Pierce, B.F.

    1986-07-01

    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.

  7. Si etching with reactive neutral beams of very low energy

    SciTech Connect (OSTI)

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Iwata, Naotaka; Hara, Tamio

    2014-12-14

    A Si etching process has been investigated with reactive neutral beams (NBs) extracted using a low acceleration voltage of less than 100 V from CF{sub 4} and Ar mixed plasmas. The etched Si profile shows that the etching process is predominantly anisotropic. The reactive NB has a constant Si etching rate in the acceleration voltage range from 20 V to 80 V. It is considered that low-energy NBs can trigger Si etching because F radicals adsorb onto the Si surface and weaken Si–Si bonds. The etching rate per unit beam flux is 33 times higher than that with Ar NB. These results show that the low-energy reactive NB is useful for damage-free high speed Si etching.

  8. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    SciTech Connect (OSTI)

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  9. Measurement of the density profile of pure and seeded molecular beams by femtosecond ion imaging

    SciTech Connect (OSTI)

    Meng, Congsen; Janssen, Maurice H. M.

    2015-02-15

    Here, we report on femtosecond ion imaging experiments to measure the density profile of a pulsed supersonic molecular beam. Ion images are measured for both a molecular beam and bulk gas under identical experimental conditions via femtosecond multiphoton ionization of Xe atoms. We report the density profile of the molecular beam, and the measured absolute density is compared with theoretical calculations of the centre line beam density. Subsequently, we discuss reasons accounting for the differences between measurements and calculations and propose that strong skimmer interference is the most probable cause for the differences. Furthermore, we report on experiments measuring the centre line density of seeded supersonic beams. The femtosecond ion images show that seeding the heavy Xe atom at low relative seed fractions (1%-10%) in a light carrier gas like Ne results in strong relative enhancements of up to two orders of magnitude.

  10. Experimental study of proton beam halo in mismatched beams

    SciTech Connect (OSTI)

    Allen, C. K.; Chan, K. D.; Colestock, P. L. ,; Garnett, R. W.; Gilpatrick, J. D.; Qiang, J.; Lysenko, W. P.; Smith, H. V.; Schneider, J. D.; Sheffield, R. L.; Wangler, Thomas P.,; Schulze, M. E.; Crandall, K. R.

    2002-01-01

    We report measurements of transverse beam-halo formation in mismatched proton beams in a 52-quadrupole FODO-transport channel following the 6.7 MeV RFQ at the Low-Energy Demonstration Accelerator (LEDA) at Los Alamos. Beam profiles in both transverse planes were measured using a new diagnostic device that consists of a movable carbon filament for measurement of the beam core, and scraper plates for measurement of the outer part of the distributions. The initial results indicate a surprisingly strong growth rate of the rms emittance even for the modest space-charge tune depressions of the experiment. Our results are consistent with the complete transfer of free energy of the mismatched beams into emittance growth within 10 envelope oscillations for both the breathing and the quadrupole modes.

  11. Cherenkov Light-based Beam Profiling for Ultrarelativistic Electron Beams

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

    Adli, E.; Gessner, S. J.; Corde, S.; Hogan, M. J.; Bjerke, H. H.

    2015-02-09

    We describe a beam profile monitor design based on Cherenkov light emitted from a charged particle beam in an air gap. The main components of the profile monitor are silicon wafers used to reflect Cherenkov light onto a camera lens system. The design allows for measuring large beam sizes, with large photon yield per beam charge and excellent signal linearity with beam charge. Furthermore, the profile monitor signal is independent of the particle energy for ultrarelativistic particles. Different design and parameter considerations are discussed. A Cherenkov light-based profile monitor has been installed at the FACET User Facility at SLAC. Finally,more » we report on the measured performance of this profile monitor.« less

  12. Quantifying sources and sinks of reactive gases in the lower atmosphere using airborne flux observations

    SciTech Connect (OSTI)

    Wolfe, Glenn; Hanisco, T. F.; Atkinson, H. L.; Bui, Thaopaul; Crounse, J. D.; Dean-Day, J.; Goldstein, Allen H.; Guenther, Alex B.; Hall, S. R.; Huey, L. G.; Jacob, D.; Karl, T.; Kim, P. S.; Liu, X.; Marvin, M. R.; Mikoviny, Tomas; Misztal, Pawel K.; Nguyen, Tran B.; Peischl, Jeff; Pollack, Ilana; Ryerson, T. B.; St Clair, J. M.; Teng, A. P.; Travis, Katherine; Ullmann, K.; Wennberg, P. O.; Wisthaler, Armin

    2015-10-16

    Atmospheric composition is governed by the interplay of emissions, chemistry, deposition, and transport. Substantial questions surround each of these processes, especially in forested environments with strong biogenic emissions. Utilizing aircraft observations acquired over a forest in the southeast U.S., we calculate eddy covariance fluxes for a suite of reactive gases and apply the synergistic information derived from this analysis to quantify emission and deposition fluxes, oxidant concentrations, aerosol uptake coefficients, and other key parameters. Evaluation of results against state-of-the-science models and parameterizations provides insight into our current understanding of this system and frames future observational priorities. As a near-direct measurement of fundamental process rates, airborne fluxes offer a new tool to improve biogenic and anthropogenic emissions inventories, photochemical mechanisms, and deposition parameterizations.

  13. Simulation of Electric Field in Semi Insulating Au/CdTe/Au Detector under Flux

    SciTech Connect (OSTI)

    Franc, J.; James, R.; Grill, R.; Kubat, J.; Belas, E.; Hoschl, P.; Moravec, P.; Praus, P.

    2009-08-02

    We report our simulations on the profile of the electric field in semi insulating CdTe and CdZnTe with Au contacts under radiation flux. The type of the space charge and electric field distribution in the Au/CdTe/Au structure is at high fluxes result of a combined influence of charge formed due to band bending at the electrodes and from photo generated carriers, which are trapped at deep levels. Simultaneous solution of drift-diffusion and Poisson equations is used for the calculation. We show, that the space charge originating from trapped photo-carriers starts to dominate at fluxes 10{sup 15}-10{sup 16}cm{sup -2}s{sup -1}, when the influence of contacts starts to be negligible.

  14. SSRL BEAM PORT SCHEDULE

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

    5-4 Nov. 05, 2007 Nov. 06, 2007 Nov. 07, 2007 Nov. 08, 2007 Nov. 09, 2007 Nov. 10, 2007 Nov. 11, 2007 Unscheduled 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU CHANGE/8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU BEAM LINE 8-1 Nov. 05, 2007 Nov. 06, 2007 Nov. 07, 2007 Nov. 08, 2007 Nov. 09, 2007 Nov. 10, 2007 Nov. 11, 2007 8821 D.Brehmer 8821 D.Brehmer 8821 D.Brehmer 3064* S.SUN 3075

  15. SSRL BEAM PORT SCHEDULE

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

    5-4 Nov. 10, 2008 Nov. 11, 2008 Nov. 12, 2008 Nov. 13, 2008 Nov. 14, 2008 Nov. 15, 2008 Nov. 16, 2008 DOWN 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU BEAM LINE 8-1 Nov. 10, 2008 Nov. 11, 2008 Nov. 12, 2008 Nov. 13, 2008 Nov. 14, 2008 Nov. 15, 2008 Nov. 16, 2008 DOWN DOWN DOWN DOWN DOWN 3064 S.SUN 3064 S.SUN DOWN DOWN DOWN DOWN VUV CHECKOUT

  16. SSRL BEAM PORT SCHEDULE

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

    5-4 Oct. 26, 2009 Oct. 27, 2009 Oct. 28, 2009 Oct. 29, 2009 Oct. 30, 2009 Oct. 31, 2009 Nov. 01, 2009 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU 8820* D.LU BEAM LINE 8-1 Oct. 26, 2009 Oct. 27, 2009 Oct. 28, 2009 Oct. 29, 2009 Oct. 30, 2009 Oct. 31, 2009 Nov. 01, 2009 Unscheduled Unscheduled Unscheduled Unscheduled

  17. SSRL BEAM PORT SCHEDULE

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

    5-4 Nov. 15, 2010 Nov. 16, 2010 Nov. 17, 2010 Nov. 18, 2010 Nov. 19, 2010 Nov. 20, 2010 Nov. 21, 2010 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU 8820 D.LU BEAM LINE 8-1 Nov. 15, 2010 Nov. 16, 2010 Nov. 17, 2010 Nov. 18, 2010 Nov. 19, 2010 Nov. 20, 2010 Nov. 21, 2010 Unscheduled Unscheduled Unscheduled 3269 S.SUN 3269 S.SUN 3269 S.SUN 3269

  18. SSRL BEAM PORT SCHEDULE

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

    1-4 Nov. 10, 2008 Nov. 11, 2008 Nov. 12, 2008 Nov. 13, 2008 Nov. 14, 2008 Nov. 15, 2008 Nov. 16, 2008 DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN DOWN BEAM LINE 2-1 Nov. 10, 2008 Nov. 11, 2008 Nov. 12, 2008 Nov. 13, 2008 Nov. 14, 2008 Nov. 15, 2008 Nov. 16, 2008 DOWN 8859 B.JOHNSON 8051* M.TONEY 8051* M.TONEY 8051* M.TONEY 3205 M.BIBEE 3205 M.BIBEE Xray CHECKOUT/8859 CHANGE/8051* M.TON 8051* M.TONEY 8051* M.TONEY Xray CHECKOUT/3205 3205

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

    SciTech Connect (OSTI)

    Isobe, M. Takeiri, Y.; Ogawa, K.; Miyake, H.; Hayashi, H.; Kobuchi, T.; Nakano, Y.; Watanabe, K.; Uritani, A.; Misawa, T.; Nishitani, T.; Tomitaka, M.; Kumagai, T.; Mashiyama, Y.; Ito, D.; Kono, S.; Yamauchi, M.

    2014-11-15

    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.

  20. Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

    SciTech Connect (OSTI)

    Osswald, F. Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A.

    2014-12-15

    The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

  1. Production of fullerenes using concentrated solar flux

    DOE Patents [OSTI]

    Fields, Clark L.; Pitts, John Roland; King, David E.; Hale, Mary Jane; Bingham, Carl E.; Lewandowski, Allan A.

    2000-01-01

    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.

  2. EUV mirror based absolute incident flux detector

    DOE Patents [OSTI]

    Berger, Kurt W.

    2004-03-23

    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.

  3. Defect-free ultrahigh flux asymmetric membranes

    DOE Patents [OSTI]

    Pinnau, Ingo; Koros, William J.

    1990-01-01

    Defect-free, ultrahigh flux integrally-skinned asymmetric membranes having extremely thin surface layers (<0.2 .mu.m) comprised of glassy polymers are disclosed. The membranes are formed by casting an appropriate drope followed by forced convective evaporation of solvent to obtain a dry phase separated asymmetrical structure. The structure is then washed in a precipitation liquid and dried.

  4. SYNOPTIC MAPPING OF CHROMOSPHERIC MAGNETIC FLUX

    SciTech Connect (OSTI)

    Jin, C. L.; Harvey, J. W.; Pietarila, A. E-mail: jharvey@nso.edu

    2013-03-10

    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.

  5. FLUX SENSOR EVALUATIONS AT THE ATR CRITICAL FACILITY

    SciTech Connect (OSTI)

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

    2010-11-01

    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 ATRCs 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

  6. Comparison of 10. 7 CM radio flux with SME solar Lyman alpha flux

    SciTech Connect (OSTI)

    Barth, C.A.; Tobiska, W.K.; Rottman, G.J. ); White, O.R.

    1990-04-01

    Measurements of the solar Lyman alpha flux that were made over a seven-and-one-half-year period between October 11, 1981 and April 13, 1989 have been compared with ground-based measurements of the solar 10.7 cm radio flux made over the same time period. There is a long-term correlation between these two measures of solar flux during the declining part of the solar cycle. During the solar minimum period, there is only a poor correlation between the two solar fluxes because the 10.7 cm radio flux reaches a minimum of 65 {times} 10{sup {minus}22} W m{sup {minus}2} Hz{sup {minus}1} and does not vary below this value while the Lyman alpha flux continues to decline and show long-term and short-term variations. During the early ascending phase of the new solar cycle, there is again a correlation between the two fluxes, although the constant of proportionality between the two is different from the constant during the declining phase of the previous solar cycle. Somewhat later, during the period November 25, 1988-April 13, 1989 a medium-term correlation exists and the proportionality of the two indices is once again similar to what it was during the declining phase of the previous solar cycle. A study of the correlation of the 10.7 cm flux with the Lyman alpha for a 999-day period during the declining phase showed that for the short-term (27-day) variation there is a correlation between the two fluxes but the proportionality between them varies from one solar rotation to the next.

  7. Broad-band beam buncher

    DOE Patents [OSTI]

    Goldberg, D.A.; Flood, W.S.; Arthur, A.A.; Voelker, F.

    1984-03-20

    A broad-band beam bunther 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-

  8. Dark matter beams at LBNF

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

    Coloma, Pilar; Dobrescu, Bogdan A.; Frugiuele, Claudia; Harnik, Roni

    2016-04-08

    High-intensity neutrino beam facilities may produce a beam of light dark matter when protons strike the target. Searches for such a dark matter beam using its scattering in a nearby detector must overcome the large neutrino background. We characterize the spatial and energy distributions of the dark matter and neutrino beams, focusing on their differences to enhance the sensitivity to dark matter. We find that a dark matter beam produced by a Zmore » $$^{'}$$ boson in the GeV mass range is both broader and more energetic than the neutrino beam. The reach for dark matter is maximized for a detector sensitive to hard neutral-current scatterings, placed at a sizable angle off the neutrino beam axis. In the case of the Long-Baseline Neutrino Facility (LBNF), a detector placed at roughly 6 degrees off axis and at a distance of about 200 m from the target would be sensitive to Z$$^{'}$$ couplings as low as 0.05. This search can proceed symbiotically with neutrino measurements. We also show that the MiniBooNE and MicroBooNE detectors, which are on Fermilab’s Booster beamline, happen to be at an optimal angle from the NuMI beam and could perform searches with existing data. As a result, this illustrates potential synergies between LBNF and the short-baseline neutrino program if the detectors are positioned appropriately.« less

  9. SU-E-T-464: On the Equivalence of the Quality Correction Factor for Pencil Beam Scanning Proton Therapy

    SciTech Connect (OSTI)

    Sorriaux, J; Paganetti, H; Testa, M; Giantsoudi, D; Schuemann, J; Bertrand, D; Orban de Xivry, J.; Lee, J; Palmans, H; Vynckier, S; Sterpin, E

    2014-06-01

    Purpose: In current practice, most proton therapy centers apply IAEA TRS-398 reference dosimetry protocol. Quality correction factors (kQ) take into account in the dose determination process the differences in beam qualities used for calibration unit and for treatment unit. These quality correction factors are valid for specific reference conditions. TRS-398 reference conditions should be achievable in both scattered proton beams (i.e. DS) and scanned proton beams (i.e. PBS). However, it is not a priori clear if TRS-398 kQ data, which are based on Monte Carlo (MC) calculations in scattered beams, can be used for scanned beams. Using TOPAS-Geant4 MC simulations, the study aims to determine whether broad beam quality correction factors calculated in TRS-398 can be directly applied to PBS delivery modality. Methods: As reference conditions, we consider a 101010 cm{sup 3} homogeneous dose distribution delivered by PBS system in a water phantom (32/10 cm range/modulation) and an air cavity placed at the center of the spread-out-Bragg-peak. In order to isolate beam differences, a hypothetical broad beam is simulated. This hypothetical beam reproduces exactly the same range modulation, and uses the same energy layers than the PBS field. Ion chamber responses are computed for the PBS and hypothetical beams and then compared. Results: For an air cavity of 220.2 cm{sup 3}, the ratio of ion chamber responses for the PBS and hypothetical beam qualities is 0.9991 0.0016. Conclusion: Quality correction factors are insensitive to the delivery pattern of the beam (broad beam or PBS), as long as similar dose distributions are achieved. This investigation, for an air cavity, suggests that broad beam quality correction factors published in TRS-398 can be applied for scanned beams. J. Sorriaux is financially supported by a public-private partnership involving the company Ion Beam Applications (IBA)

  10. Spectroscopic investigation of the spatiotemporal dynamics of an electric field in plasma of a beam-type high-voltage discharge in helium

    SciTech Connect (OSTI)

    Demkin, V. P.; Mel'nichuk, S. V.

    2015-02-15

    In the present work, a method of determining the spatiotemporal characteristics of the electric field strength in an accelerating gap and a plasma flare of a beam-type high-voltage pulsed discharge in He at moderate pressure is presented. The method is based on spectroscopic data on the Stark splitting of π-components of He 2P–4Q transitions; Q = D(4921.93 Å), F(4920.35 Å) in the near-cathode region of the discharge and on the spatiotemporal characteristics of intensities of He(2s{sup 1}S–3p{sup 1}P{sup 0}) spectral lines with λ = 5015 Å and He{sup +}(3d–4f) spectral lines with λ = 4685 Å measured experimentally and calculated from the data of statistical simulation of the electron kinetics by the Monte Carlo method. The shape and strength of the electric field of the space charge in the interelectrode gap and the drift region of the discharge are estimated. It is demonstrated that the electric field created by the current pulse of uncompensated space charge in the near-anode region changes the discharge regime and causes degradation of the electron beam in the plasma flare. It is established that the flux of secondary electrons from the drift region to the anode has significant effect on the radiation intensity distribution in this region of the discharge.

  11. Measurements of aperture and beam lifetime using movable beam scrapers in Indus-2 electron storage ring

    SciTech Connect (OSTI)

    Kumar, Pradeep; Ghodke, A. D.; Karnewar, A. K.; Holikatti, A. C.; Yadav, S.; Puntambekar, T. A.; Singh, G.; Singh, P.

    2013-12-15

    In this paper, the measurements of vertical and horizontal aperture which are available for stable beam motion in Indus-2 at beam energy 2.5 GeV using movable beam scrapers are presented. These beam scrapers are installed in one of the long straight sections in the ring. With the movement of beam scrapers towards the beam centre, the beam lifetime is measured. The beam lifetime data obtained from the movement of vertical and horizontal beam scrapers are analyzed. The contribution of beam loss due to beam-gas scattering (vacuum lifetime) and electron-electron scattering within a beam bunch (Touschek lifetime) is separated from the measured beam lifetime at different positions of the beam scrapers. Vertical and horizontal beam sizes at scrapers location are estimated from the scraper movement towards the beam centre in quantum lifetime limit and their values closely agree with measured value obtained using X-ray diagnostic beamline.

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

    SciTech Connect (OSTI)

    Halfon, S.; Feinberg, G.; Paul, M.; Arenshtam, A.; Berkovits, D.; Kijel, D.; Nagler, A.; Eliyahu, I.; Silverman, I.

    2013-04-19

    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. Beam loading in a laser-plasma accelerator using a near-hollow plasma channel

    SciTech Connect (OSTI)

    Schroeder, C. B.; Benedetti, C.; Esarey, E.; Leemans, W. P.

    2013-12-15

    Beam loading in laser-plasma accelerators using a near-hollow plasma channel is examined in the linear wake regime. It is shown that, by properly shaping and phasing the witness particle beam, high-gradient acceleration can be achieved with high-efficiency, and without induced energy spread or emittance growth. Both electron and positron beams can be accelerated in this plasma channel geometry. Matched propagation of electron beams can be achieved by the focusing force provided by the channel density. For positron beams, matched propagation can be achieved in a hollow plasma channel with external focusing. The efficiency of energy transfer from the wake to a witness beam is calculated for single ultra-short bunches and bunch trains.

  14. The effects of the RHIC E-lenses magnetic structure layout on the proton beam trajectory

    SciTech Connect (OSTI)

    Gu, X.; Pikin, A.; Luo, Y.; Okamura, M.; Fischer, W.; Gupta, R.; Hock, J.; Raparia, D.

    2011-03-28

    We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed in RHIC IR10. First, the layout of these two E-lenses is introduced. Then the effects of e-lenses on proton beam are discussed. For example, the transverse fields of the e-lens bending solenoids and the fringe field of the main solenoids will shift the proton beam. For the effects of the e-lens on proton beam trajectory, we calculate the transverse kicks that the proton beam receives in the electron lens via Opera at first. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.

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

    SciTech Connect (OSTI)

    Stancari, Giulio

    2014-03-25

    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.

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

    SciTech Connect (OSTI)

    Dalaryd, Mrten Kns, Tommy; Ceberg, Crister

    2014-11-01

    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 SpencerAttix 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 AAPMs 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

  17. Facility for high heat flux testing of irradiated fusion materials and components using infrared plasma arc lamps

    SciTech Connect (OSTI)

    Sabau, Adrian S; Ohriner, Evan Keith; Kiggans, Jim; Harper, David C; Snead, Lance Lewis; Schaich, Charles Ross

    2014-01-01

    A new high-heat flux testing facility using water-wall stabilized high-power high-pressure argon Plasma Arc Lamps (PALs) has been developed for fusion applications. It can handle irradiated plasma facing component materials and mock-up divertor components. Two PALs currently available at ORNL can provide maximum incident heat fluxes of 4.2 and 27 MW/m2 over a heated area of 9x12 and 1x10 cm2, respectively, which are fusion-prototypical steady state heat flux conditions. The facility will be described and the main differences between the photon-based high-heat flux testing facilities, such as PALs, and the e-beam and particle beam facilities more commonly used for fusion HHF testing are discussed. The components of the test chamber were designed to accommodate radiation safety and materials compatibility requirements posed by high-temperature exposure of low levels irradiated tungsten articles. Issues related to the operation and temperature measurements during testing are presented and discussed.

  18. Fundamental aspects of deuterium retention in tungsten at high flux plasma exposure

    SciTech Connect (OSTI)

    Ogorodnikova, O. V.

    2015-08-21

    An effect of enhanced trapping of deuterium in tungsten at high flux was discovered. It was shown analytically and confirmed experimentally that the deuterium trapping in a presence of high density of defects in tungsten (W) depends on the ion energy and ion flux. Newly developed analytical model explains experimentally observed discrepancy of deuterium trapping at radiation-induced defects in tungsten at different ion fluxes that significantly improves a prediction of hydrogen isotope accumulation in different plasma devices, including ITER and DEMO. The developed model can be used for many system of hydrogen in a metal in both normal and extreme environments (high fluxes, elevated temperatures, neutron irradiation, etc.). This new model allows, for the first time, to validate density function theory (DFT) predictions of multiple occupation of a defect with deuterium against experimental data that bridge the gap in length and time scale between DFT calculations and experiments. By comparing first-principle calculations based on DFT and semi-empirical “adsorption model,” it was proved that the mechanism of hydrogen isotope trapping in a vacancy cluster is similar to a chemisorption on a surface. Binding energies of deuterium with different types of defects in W were defined. Moreover, the surface barrier of deuterium to be chemisorbed on a clean W surface was found to be less than 1 eV and kinetics of deuterium release is limited by de-trapping from defects rather than to be limited by surface effects.

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

    SciTech Connect (OSTI)

    Melchior, M; Salinas Aranda, F; Sciutto, S; Dodat, D; Larragueta, N

    2014-06-01

    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

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

    SciTech Connect (OSTI)

    Lidia, Steven M.

    1999-11-01

    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

  1. Beam-halo measurements in high-current proton beams

    SciTech Connect (OSTI)

    Allen, C.K.; Chan, K.C.D.; Colestock, P.L.; Crandall, K.R.; Garnett, R.W.; Gilpatrick, J.D.; Lysenko, W.; Qiang, J.; Schneider, J.D.; Schulze, M.E.; Sheffield, R.L.; Smith, H.V.; Wangler, T.P.

    2002-01-11

    We present results from an experimental study of the beam halo in a high-current 6.7-MeV proton beam propagating through a 52-quadrupole periodic-focusing channel. The gradients of the first four quadrupoles were independently adjusted to match or mismatch the injected beam. Emittances and beamwidths were obtained from measured profiles for comparisons with maximum emittance-growth predictions of a free-energy model and maximum halo-amplitude predictions of a particle-core model. The experimental results support both models and the present theoretical picture of halo formation.

  2. BEAM-BEAM SIMULATIONS FOR THE ERHIC ELECTRON RING.

    SciTech Connect (OSTI)

    MONTAG, C.

    2005-05-16

    To study collisions between polarized electrons and heavy ions or polarized protons at high energy, adding a 10 GeV electron storage ring to the existing RHIC facility is currently under consideration. To achieve high luminosities of several 10{sup 33} cm{sup -2} sec{sup -1} range, a vertical beam-beam tuneshift parameter of {zeta}{sub y} = 0.08 is required for the electron beam. Simulation studies are being performed to study the feasibility of this high tuneshift parameter and explore the potential for even higher tuneshifts. Recent results of these studies are presented.

  3. 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.

    2005-08-29

    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.

  4. Laser beam alignment apparatus and method

    DOE Patents [OSTI]

    Gruhn, C.R.; Hammond, R.B.

    The disclosure related 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.

  5. Laser beam alignment apparatus and method

    DOE Patents [OSTI]

    Gruhn, Charles R.; Hammond, Robert B.

    1981-01-01

    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.

  6. Ion-beam-induced bending of freestanding amorphous nanowires: The importance of the substrate material and charging

    SciTech Connect (OSTI)

    Cui, Ajuan; Li, Wuxia; Liu, Zhe; Luo, Qiang; Gu, Changzhi; Fenton, J. C.; Shen, Tiehan H.

    2013-05-27

    Ion-beam irradiation offers great flexibility and controllability in the construction of freestanding nanostructures with multiple advanced functionalities. Here, we present and discuss the bending of free-standing nanowires, against, towards, and ultimately parallel to a flux of directional ion irradiation. Bending components both along and perpendicular to the incident ion beam were observed, and the bending behavior was found to depend both on the ion beam scanning strategy and on the conductivity of the supporting substrate. This behavior is explained by an ion-irradiation-related electrostatic interaction. Our findings suggest the prospect of exploiting this technique to engineer 3D nanostructures for advanced applications.

  7. Benchmark of numerical tools simulating beam propagation and secondary particles in ITER NBI

    SciTech Connect (OSTI)

    Sartori, E. Veltri, P.; Serianni, G.; Dlougach, E.; Hemsworth, R.; Singh, M.

    2015-04-08

    Injection of high energy beams of neutral particles is a method for plasma heating in fusion devices. The ITER injector, and its prototype MITICA (Megavolt ITER Injector and Concept Advancement), are large extrapolations from existing devices: therefore numerical modeling is needed to set thermo-mechanical requirements for all beam-facing components. As the power and charge deposition originates from several sources (primary beam, co-accelerated electrons, and secondary production by beam-gas, beam-surface, and electron-surface interaction), the beam propagation along the beam line is simulated by comprehensive 3D models. This paper presents a comparative study between two codes: BTR has been used for several years in the design of the ITER HNB/DNB components; SAMANTHA code was independently developed and includes additional phenomena, such as secondary particles generated by collision of beam particles with the background gas. The code comparison is valuable in the perspective of the upcoming experimental operations, in order to prepare a reliable numerical support to the interpretation of experimental measurements in the beam test facilities. The power density map calculated on the Electrostatic Residual Ion Dump (ERID) is the chosen benchmark, as it depends on the electric and magnetic fields as well as on the evolution of the beam species via interaction with the gas. Finally the paper shows additional results provided by SAMANTHA, like the secondary electrons produced by volume processes accelerated by the ERID fringe-field towards the Cryopumps.

  8. Home Energy Score Calculation Methodology

    Broader source: Energy.gov [DOE]

    A Qualified Assessor calculates the Home Energy Score by first conducting a brief walk-through of the home and collecting approximately 40 data points. Next, the Qualified Assessor uses the Home...

  9. Electrostatic wire stabilizing a charged particle beam

    DOE Patents [OSTI]

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

    1983-03-21

    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.

  10. Coherent instabilities of a relativistic bunched beam

    SciTech Connect (OSTI)

    Chao, A.W.

    1982-06-01

    A charge-particle beam contained in an accelerator vacuum chamber interacts electromagnetically with its environment to create a wake field. This field than acts back on the beam, perturbing the particle motion. If the beam intensity is high enough, this beam-environment interaction may lead to an instability and to subsequent beam loss. The beam and its environment form a dynamical system, and it is this system that will be studied. 84 references.

  11. Transfer Area Mechanical Handling Calculation

    SciTech Connect (OSTI)

    B. Dianda

    2004-06-23

    This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use of these components or their related

  12. TRACE3D. Interactive Beam-Dynamics Program

    SciTech Connect (OSTI)

    Singleton, L.; Yao, C.Y.

    1993-12-01

    TRACE3D is an interactive program that calculates the envelopes of a bunched beam, including linear space-charge forces, through a user-defined system. The transport system may consist of the following elements: drift, thin lens, quadrupole, permanent magnet quadrupole, solenoid, doublet, triplet, bending magnet, edge angle (for bend), RF gap, radio-frequency-quadrupole cell, RF cavity, coupled-cavity tank, user-desired element, coordinate rotation, and identical element. The beam is represented by a 6X6 matrix defining a hyper-ellipsoid in six-dimensional phase space. The projection of this hyperellipsoid on any two-dimensional plane is an ellipse that defines the boundary of the beam in that plane.

  13. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, John W.; O'Brien, Dennis W.

    1996-01-01

    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.

  14. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, J.W.; O`Brien, D.W.

    1996-07-09

    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.

  15. CONTINUOUS EXTRACTED BEAM IN THE AGS FAST EXTERNAL BEAM LINE.

    SciTech Connect (OSTI)

    GLENN,J.W.; TSOUPAS,N.; BROWN,K.A.; BIRYUKOV,V.M.

    2001-06-18

    A method to split off a few percent of the 6 x 10{sup 13} AGS beam delivered to the Slow External Beam (SEB) lines and send it down the Fast External Beam line (FEB) has been developed. The mission is to feed a counter experiment off the FEB that directly measures the neutrino mass using the muon storage ring. The use of normal thin septum splitters would have an excessive loss overhead and been optically difficult. The AGS Slow Extraction uses a third integer resonance with sextuple strength so the resonance width is a few percent of the beam width. This results in a low density tail which will be clipped by a bent crystal and deflected into the FEB channel. This clipping off of the tail should reduce losses in the SEB transport line. Details of modeled orbits, particle distribution and extraction trajectories into and out off the crystal will be given.

  16. Identifying and bounding uncertainties in nuclear reactor thermal power calculations

    SciTech Connect (OSTI)

    Phillips, J.; Hauser, E.; Estrada, H.

    2012-07-01

    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

  17. Reflected beam illumination microscopy using a microfluidics...

    Office of Scientific and Technical Information (OSTI)

    Reflected beam illumination microscopy using a microfluidics device - progress report 6152014. Citation Details In-Document Search Title: Reflected beam illumination microscopy ...

  18. Probing Organic Transistors with Infrared Beams

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

    Probing Organic Transistors with Infrared Beams Probing Organic Transistors with Infrared Beams Print Wednesday, 26 July 2006 00:00 Silicon-based transistors are well-understood,...

  19. Bayesian hierarchical models for soil CO{sub 2} flux and leak detection at geologic sequestration sites

    SciTech Connect (OSTI)

    Yang, Ya-Mei; Small, Mitchell J.; Junker, Brian; Bromhal, Grant S.; Strazisar, Brian; Wells, Arthur

    2011-10-01

    Proper characterizations of background soil CO{sub 2} respiration rates are critical for interpreting CO{sub 2} leakage monitoring results at geologic sequestration sites. In this paper, a method is developed for determining temperature-dependent critical values of soil CO{sub 2} flux for preliminary leak detection inference. The method is illustrated using surface CO{sub 2} flux measurements obtained from the AmeriFlux network fit with alternative models for the soil CO{sub 2} flux versus soil temperature relationship. The models are fit first to determine pooled parameter estimates across the sites, then using a Bayesian hierarchical method to obtain both global and site-specific parameter estimates. Model comparisons are made using the deviance information criterion (DIC), which considers both goodness of fit and model complexity. The hierarchical models consistently outperform the corresponding pooled models, demonstrating the need for site-specific data and estimates when determining relationships for background soil respiration. A hierarchical model that relates the square root of the CO{sub 2} flux to a quadratic function of soil temperature is found to provide the best fit for the AmeriFlux sites among the models tested. This model also yields effective prediction intervals, consistent with the upper envelope of the flux data across the modeled sites and temperature ranges. Calculation of upper prediction intervals using the proposed method can provide a basis for setting critical values in CO{sub 2} leak detection monitoring at sequestration sites.

  20. Energy flux density in a thermoacoustic couple

    SciTech Connect (OSTI)

    Cao, N.; Chen, S. |; Olson, R.; Swift, G.W.

    1996-06-01

    The hydro- and thermodynamical processes near and within a thermoacoustic couple are simulated and analyzed by numerical solution of the compressible Navier-Stokes, continuity, and energy equations for an ideal gas, concentrating on the time-averaged energy flux density in the gas. The numerical results show details of the heat sink at one end of the plates in the thermoacoustic couple. 15 refs., 10 figs., 1 tab.

  1. Monitoring external beam radiotherapy using real-time beam visualization

    SciTech Connect (OSTI)

    Jenkins, Cesare H.; Naczynski, Dominik J.; Yu, Shu-Jung S.; Xing, Lei

    2015-01-15

    Purpose: To characterize the performance of a novel radiation therapy monitoring technique that utilizes a flexible scintillating film, common optical detectors, and image processing algorithms for real-time beam visualization (RT-BV). Methods: Scintillating films were formed by mixing Gd{sub 2}O{sub 2}S:Tb (GOS) with silicone and casting the mixture at room temperature. The films were placed in the path of therapeutic beams generated by medical linear accelerators (LINAC). The emitted light was subsequently captured using a CMOS digital camera. Image processing algorithms were used to extract the intensity, shape, and location of the radiation field at various beam energies, dose rates, and collimator locations. The measurement results were compared with known collimator settings to validate the performance of the imaging system. Results: The RT-BV system achieved a sufficient contrast-to-noise ratio to enable real-time monitoring of the LINAC beam at 20 fps with normal ambient lighting in the LINAC room. The RT-BV system successfully identified collimator movements with sub-millimeter resolution. Conclusions: The RT-BV system is capable of localizing radiation therapy beams with sub-millimeter precision and tracking beam movement at video-rate exposure.

  2. Observations and open questions in beam-beam interactions

    SciTech Connect (OSTI)

    Sen, Tanaji; /Fermilab

    2010-08-01

    The first of the hadron colliders, ISR, started operation in 1970. In the following years, the hadron colliders to follow were the SPS (started 1980), the Tevatron (started 1987 first as a fixed target machine), RHIC (started 2000) and most recently the LHC, which started in 2008. HERA was a hybrid that collided electrons and protons. All of these accelerators had or have their performance limited by the effects of the beam-beam interactions. That has also been true for the electron-positron colliders such as LEP, CESR, KEKB and PEPII. In this article I will discuss how the beam-beam limitations arose in some of these machines. The discussion will be focused on common themes that span the different colliders. I will mostly discuss the hadron colliders but sometimes discuss the lepton colliders where relevant. Only a handful of common accelerator physics topics are chosen here, the list is not meant to be exhaustive. A comparative review of beam-beam performance in the ISR, SPS and Tevatron (ca 1989) can be found in reference. Table 1 shows the relevant parameters of colliders (excluding the LHC), which have accelerated protons.

  3. Design of An 18 MW Beam Dump for 500 GeV Electron/Positron Beams at An ILC

    SciTech Connect (OSTI)

    Amann, John; Arnold, Ray; Seryi, Andrei; Walz, Dieter; Kulkarni, Kiran; Rai, Pravin; Satyamurthy, Polepalle; Tiwari, Vikar; Vincke, Heinz; /CERN

    2012-07-05

    This article presents a report on the progress made in designing 18 MW water based Beam Dumps for electrons or positrons for an International Linear Collider (ILC). Multi-dimensional technology issues have to be addressed for the successful design of the Beam Dump. They include calculations of power deposition by the high energy electron/positron beam bunch trains, computational fluid dynamic analysis of turbulent water flow, mechanical design, process flow analysis, hydrogen/oxygen recombiners, handling of radioactive 7Be and 3H, design of auxiliary equipment, provisions for accident scenarios, remote window exchanger, radiation shielding, etc. The progress made to date is summarized, the current status, and also the issues still to be addressed.

  4. Adsorption calorimetry during metal vapor deposition on single crystal surfaces: Increased flux, reduced optical radiation, and real-time flux and reflectivity measurements

    SciTech Connect (OSTI)

    Sellers, Jason R. V.; James, Trevor E.; Hemmingson, Stephanie L.; Farmer, Jason A.; Campbell, Charles T.

    2013-12-15

    Thin films of metals and other materials are often grown by physical vapor deposition. To understand such processes, it is desirable to measure the adsorption energy of the deposited species as the film grows, especially when grown on single crystal substrates where the structure of the adsorbed species, evolving interface, and thin film are more homogeneous and well-defined in structure. Our group previously described in this journal an adsorption calorimeter capable of such measurements on single-crystal surfaces under the clean conditions of ultrahigh vacuum [J. T. Stuckless, N. A. Frei, and C. T. Campbell, Rev. Sci. Instrum. 69, 2427 (1998)]. Here we describe several improvements to that original design that allow for heat measurements with ∼18-fold smaller standard deviation, greater absolute accuracy in energy calibration, and, most importantly, measurements of the adsorption of lower vapor-pressure materials which would have previously been impossible. These improvements are accomplished by: (1) using an electron beam evaporator instead of a Knudsen cell to generate the metal vapor at the source of the pulsed atomic beam, (2) changing the atomic beam design to decrease the relative amount of optical radiation that accompanies evaporation, (3) adding an off-axis quartz crystal microbalance for real-time measurement of the flux of the atomic beam during calorimetry experiments, and (4) adding capabilities for in situ relative diffuse optical reflectivity determinations (necessary for heat signal calibration). These improvements are not limited to adsorption calorimetry during metal deposition, but also could be applied to better study film growth of other elements and even molecular adsorbates.

  5. Circular, confined distribution for charged particle beams

    DOE Patents [OSTI]

    Garnett, Robert W.; Dobelbower, M. Christian

    1995-01-01

    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.

  6. Circular, confined distribution for charged particle beams

    DOE Patents [OSTI]

    Garnett, R.W.; Dobelbower, M.C.

    1995-11-21

    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. The Fermilab neutrino beam program

    SciTech Connect (OSTI)

    Rameika, Regina A.; /Fermilab

    2007-01-01

    This talk presents an overview of the Fermilab Neutrino Beam Program. Results from completed experiments as well as the status and outlook for current experiments is given. Emphasis is given to current activities towards planning for a future program.

  8. Repetitively pumped electron beam device

    DOE Patents [OSTI]

    Schlitt, L.G.

    1979-07-24

    Disclosed is an apparatus for producing fast, repetitive pulses of controllable length of an electron beam by phased energy storage in a transmission line of length matched to the number of pulses and specific pulse lengths desired. 12 figs.

  9. Repetitively pumped electron beam device

    DOE Patents [OSTI]

    Schlitt, Leland G. [Livermore, CA

    1979-07-24

    Apparatus for producing fast, repetitive pulses of controllable length of an electron beam by phased energy storage in a transmission line of length matched to the number of pulses and specific pulse lengths desired.

  10. Quantum fluctuations in beam dynamics.

    SciTech Connect (OSTI)

    Kim, K.-J.

    1998-06-04

    Quantum effects could become important for particle and photon beams used in high-luminosity and high brightness applications in the current and next generation accelerators and radiation sources. This paper is a review of some of these effects.

  11. Confined energy distribution for charged particle beams

    DOE Patents [OSTI]

    Jason, Andrew J.; Blind, Barbara

    1990-01-01

    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.

  12. Traveling-wave device with mass flux suppression (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Traveling-wave device with mass flux suppression Title: Traveling-wave device with mass flux suppression A traveling-wave device is provided with the conventional moving pistons ...

  13. OSTIblog Articles in the High Flux Isotope Reactor Topic | OSTI...

    Office of Scientific and Technical Information (OSTI)

    High Flux Isotope Reactor Topic The NXS Class of 2014 by Kathy Chambers 19 Nov, 2014 in ... National Laboratory, High Flux Isotope Reactor, National School on Neutron and X-ray ...

  14. AmeriFlux US-FR3 Freeman Ranch- Woodland

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

    Heilman, Jim [Texas A& M University

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-FR3 Freeman Ranch- Woodland. Site Description - Dense canopy of live oak and Ashe juniper

  15. Single lens laser beam shaper

    DOE Patents [OSTI]

    Liu, Chuyu; Zhang, Shukui

    2011-10-04

    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.

  16. EXTERNAL CRITICALITY CALCULATION FOR DOE SNF CODISPOSAL WASTE PACKAGES

    SciTech Connect (OSTI)

    H. Radulescu

    2002-10-18

    The purpose of this document is to evaluate the potential for criticality for the fissile material that could accumulate in the near-field (invert) and in the far-field (host rock) beneath the U.S. Department of Energy (DOE) spent nuclear fuel (SNF) codisposal waste packages (WPs) as they degrade in the proposed monitored geologic repository at Yucca Mountain. The scope of this calculation is limited to the following DOE SNF types: Shippingport Pressurized Water Reactor (PWR), Enrico Fermi, Fast Flux Test Facility (FFTF), Fort St. Vrain, Melt and Dilute, Shippingport Light Water Breeder Reactor (LWBR), N-Reactor, and Training, Research, Isotope, General Atomics reactor (TRIGA). The results of this calculation are intended to be used for estimating the probability of criticality in the near-field and in the far-field. There are no limitations on use of the results of this calculation. The calculation is associated with the waste package design and was developed in accordance with the technical work plan, ''Technical Work Plan for: Department of Energy Spent Nuclear Fuel and Plutonium Disposition Work Packages'' (Bechtel SAIC Company, LLC [BSC], 2002a). This calculation is subject to the Quality Assurance Requirements and Description (QARD) per the activity evaluation under work package number P6212310Ml in the technical work plan TWP-MGR-MD-0000 10 REV 01 (BSC 2002a).

  17. Toroidal midplane neutral beam armor and plasma limiter

    DOE Patents [OSTI]

    Kugel, H.W.; Hand, S.W. Jr.; Ksayian, H.

    1985-05-31

    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.

  18. High heat flux engineering in solar energy applications

    SciTech Connect (OSTI)

    Cameron, C.P.

    1993-07-01

    Solar thermal energy systems can produce heat fluxes in excess of 10,000 kW/m{sup 2}. This paper provides an introduction to the solar concentrators that produce high heat flux, the receivers that convert the flux into usable thermal energy, and the instrumentation systems used to measure flux in the solar environment. References are incorporated to direct the reader to detailed technical information.

  19. Multigroup Reactor Lattice Cell Calculation

    Energy Science and Technology Software Center (OSTI)

    1990-03-01

    The Winfrith Improved Multigroup Scheme (WIMS), is a general code for reactor lattice cell calculations on a wide range of reactor systems. In particular, the code will accept rod or plate fuel geometries in either regular arrays or in clusters, and the energy group structure has been chosen primarily for thermal calculations. The basic library has been compiled with 14 fast groups, 13 resonance groups and 42 thermal groups, but the user is offered themore » choice of accurate solutions in many groups or rapid calculations in few groups. Temperature dependent thermal scattering matrices for a variety of scattering laws are available in the library for the principal moderators which include hydrogen, deuterium, graphite, beryllium and oxygen. WIMSD5 is a succesor version of WIMS-D/4.« less

  20. Insertion device calculations with mathematica

    SciTech Connect (OSTI)

    Carr, R.; Lidia, S.

    1995-02-01

    The design of accelerator insertion devices such as wigglers and undulators has usually been aided by numerical modeling on digital computers, using code in high level languages like Fortran. In the present era, there are higher level programming environments like IDL{reg_sign}, MatLab{reg_sign}, and Mathematica{reg_sign} in which these calculations may be performed by writing much less code, and in which standard mathematical techniques are very easily used. The authors present a suite of standard insertion device modeling routines in Mathematica to illustrate the new techniques. These routines include a simple way to generate magnetic fields using blocks of CSEM materials, trajectory solutions from the Lorentz force equations for given magnetic fields, Bessel function calculations of radiation for wigglers and undulators and general radiation calculations for undulators.

  1. Electron beam diagnostic for profiling high power beams

    DOE Patents [OSTI]

    Elmer, John W.; Palmer, Todd A.; Teruya, Alan T.

    2008-03-25

    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.

  2. Zero-flux planes, flux reversals and diffusion paths in ternary and quaternary diffusion

    SciTech Connect (OSTI)

    Dayananda, M.A.

    1986-05-23

    During isothermal multicomponent diffusion, interdiffusion fluxes of individual components can go to zero at zero-flux planes (ZFP) and exhibit flux reversals from one side to the other of such planes. Interdiffusion fluxes as well as the locations and compositions of ZFPs for components are determined directly from the concentration profiles of diffusion couples without the need for prior knowledge of interdiffusion coefficients. The development and identification of ZFPs is reviewed with the aid of single phase and two-phase diffusion couples investigated in the Cu-Ni-Zn system at 775/sup 0/C. ZFP locations in the diffusion zone nearly correspond to sections where the activity of a component is the same as its activity in either of the terminal alloys of a couple. Path slopes at ZFPs are uniquely dictated by the atomic mobility and thermodynamic data for the components. Discontinuous flux reversals for the components can also occur at interfaces in multiphase couples. Identification of ZFPs is also presented for diffusion in the Cu-Ni-Zn-Mn quaternary system. Analytical representation of diffusion paths for both ternary and quaternary diffusion couples is presented with the aid of characteristic path parameters.

  3. Design of a Modular E-Core Flux Concentrating Axial Flux Machine: Preprint

    SciTech Connect (OSTI)

    Husain, Tausif; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2015-08-24

    In this paper a novel E-Core axial flux machine is proposed. The machine has a double-stator, single-rotor configuration with flux-concentrating ferrite magnets and pole windings across each leg of an E-Core stator. E-Core stators with the proposed flux-concentrating rotor arrangement result in better magnet utilization and higher torque density. The machine also has a modular structure facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis. facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis.

  4. Spheromak reactor with poloidal flux-amplifying transformer

    DOE Patents [OSTI]

    Furth, Harold P.; Janos, Alan C.; Uyama, Tadao; Yamada, Masaaki

    1987-01-01

    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.

  5. Integration of Novel Flux Coupling Motor and Current Source Inverter |

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

    Department of Energy ape034_hsu_2011_p.pdf (317.88 KB) More Documents & Publications Integration of Novel Flux Coupling Motor and Current Source Inverter Novel Flux Coupling Machine without Permanent Magnets John Hsu, Oak Ridge National Laboratory, Flux Coupling Machines and Switched Reluctance Motors to Replace Permanent Magnets in Electric Vehicles

  6. Means for counteracting charged particle beam divergence

    DOE Patents [OSTI]

    Hooper, Jr., Edwin B.

    1978-01-01

    To counteract charge particle beam divergence, magnetic field-generating means are positioned along the edges of a charged particle beam to be controlled, such as to deflect and redirect particles tending to diverge from a desired beam direction. By selective arrangement of the magnetic field-generating means, the entire beam may be deflected and guided into different directions.

  7. 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.

  8. ITER Port Interspace Pressure Calculations

    SciTech Connect (OSTI)

    Carbajo, Juan J; Van Hove, Walter A

    2016-01-01

    The ITER Vacuum Vessel (VV) is equipped with 54 access ports. Each of these ports has an opening in the bioshield that communicates with a dedicated port cell. During Tokamak operation, the bioshield opening must be closed with a concrete plug to shield the radiation coming from the plasma. This port plug separates the port cell into a Port Interspace (between VV closure lid and Port Plug) on the inner side and the Port Cell on the outer side. This paper presents calculations of pressures and temperatures in the ITER (Ref. 1) Port Interspace after a double-ended guillotine break (DEGB) of a pipe of the Tokamak Cooling Water System (TCWS) with high temperature water. It is assumed that this DEGB occurs during the worst possible conditions, which are during water baking operation, with water at a temperature of 523 K (250 C) and at a pressure of 4.4 MPa. These conditions are more severe than during normal Tokamak operation, with the water at 398 K (125 C) and 2 MPa. Two computer codes are employed in these calculations: RELAP5-3D Version 4.2.1 (Ref. 2) to calculate the blowdown releases from the pipe break, and MELCOR, Version 1.8.6 (Ref. 3) to calculate the pressures and temperatures in the Port Interspace. A sensitivity study has been performed to optimize some flow areas.

  9. Petrophysical corner - calculating water cut

    SciTech Connect (OSTI)

    Elphick, R.Y. )

    1990-02-01

    The problem of determining the amount of water cut that can be expected from a well is discussed in conjunction with a program for making this calculation. The program was written for Amiga, Apple Macintosh, and MS DOS personal computers and source code for the program is provided.

  10. Semiconducting glasses with flux pinning inclusions

    DOE Patents [OSTI]

    Johnson, William L.; Poon, Siu-Joe; Duwez, Pol E.

    1981-01-01

    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.

  11. Overview of the APT high-energy beam transport and beam expanders

    SciTech Connect (OSTI)

    Shafer, R.E.; Blind, B.; Gray, E.R.

    1997-08-01

    The APT high energy beam transport (HEBT) and beam expanders convey the 1700-MeV, 100-mA cw proton beam from the linac to the tritium target/blanket assembly, or a tuning beam stop. The HEBT includes extensive beam diagnostics, collimators, and beam jitter correction, to monitor and control the 170-MW beam prior to expansion. A zero-degree beamline conveys the beam to the beam stop, and an achromatic bend conveys the beam to the tritium production target. Nonlinear beam expanders make use of higher-order multipole magnets and dithering dipoles to expand the beam to a uniform-density, 16-cm wide by 160-cm high rectangular profile on the tritium-production target. The overall optics design will be reviewed, and beam simulations will be presented.

  12. CALCULATING ENERGY STORAGE DUE TO TOPOLOGICAL CHANGES IN EMERGING ACTIVE REGION NOAA AR 11112

    SciTech Connect (OSTI)

    Tarr, Lucas; Longcope, Dana

    2012-04-10

    The minimum current corona model provides a way to estimate stored coronal energy using the number of field lines connecting regions of positive and negative photospheric flux. This information is quantified by the net flux connecting pairs of opposing regions in a connectivity matrix. Changes in the coronal magnetic field, due to processes such as magnetic reconnection, manifest themselves as changes in the connectivity matrix. However, the connectivity matrix will also change when flux sources emerge or submerge through the photosphere, as often happens in active regions. We have developed an algorithm to estimate the changes in flux due to emergence and submergence of magnetic flux sources. These estimated changes must be accounted for in order to quantify storage and release of magnetic energy in the corona. To perform this calculation over extended periods of time, we must additionally have a consistently labeled connectivity matrix over the entire observational time span. We have therefore developed an automated tracking algorithm to generate a consistent connectivity matrix as the photospheric source regions evolve over time. We have applied this method to NOAA Active Region 11112, which underwent a GOES M2.9 class flare around 19:00 on 2010 October 16th, and calculated a lower bound on the free magnetic energy buildup of {approx}8.25 Multiplication-Sign 10{sup 30} erg over 3 days.

  13. EXPERIMENTAL STUDY OF PROTON-BEAM HALO INDUCED BY BEAM MISMATCH IN LEDA.

    SciTech Connect (OSTI)

    Wangler, Thomas P.,; Allen, C. K.; Colestock, P. L. ,; Chan, K. D.; Crandall, K. R.; Garnett, R. W.; Gilpatrick, J. D.; Lysenko, W. P.; Qiang, J.; Schneider, J. D.; Sheffield, R. L.; Smith, H. V.; Schulze, M. E.

    2001-01-01

    We report measurements of transverse beam halo in mismatched proton beams in a 52-quadrupole FODO transport channel following the 6.7-MeV LEDA RFQ. Beam profiles in both transverse planes are measured using beam-profile diagnostic devices that consist of a movable carbon filament for measurement of the dense beam core, and scraper plates for measurement of the halo. The gradients of the first four quadrupoles can be independently adjusted to mismatch the RFQ output beam into the beam-transport channel. The properties of the measured mismatched beam profiles in the transport channel will be compared with predictions from multiparticle beam-dynamics simulations.

  14. eRHIC ring-ring design with head-on beam-beam compensation

    SciTech Connect (OSTI)

    Montag,C.; Blaskiewicz, M.; Pozdeyev, E.; Fischer, W.; MacKay, W. W.

    2009-05-04

    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.

  15. Multi-particle weak-strong simulation of RHIC head-on beam-beam compensation.

    SciTech Connect (OSTI)

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

    2008-06-23

    To compensate the large tune spread generated by the beam-beam interactions in the polarized proton (pp) run in the Relativistic Heavy Ion Collider (RHIC), a low energy round Gaussian electron beam or electron lens is proposed to collide head-on with the proton beam. Using a weakstrong beam-beam interaction model, we carry out multiparticle simulations to investigate the effects of head-on beam-beam compensation on the proton beam's lifetime and emittance growth. The simplectic 6-D element-by-element tracking code SixTrack is adopted and modified for this study. The code benchmarking and preliminary simulation results are presented.

  16. AmeriFlux US-WCr Willow Creek

    SciTech Connect (OSTI)

    Desai, Ankur

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-WCr Willow Creek. Site Description - Upland decduous broadleaf forest. Mainly sugar maple, also basswood. Uniform stand atop a very modest hill. Clearcut approximately 80 years ago. Chosen to be representative of the upland deciduous broadleaf forests within the WLEF tall tower flux footprint. It appears to be more heavily forested and more productive than most of the upland deciduous broadleaf forests in the WLEF flux footprint (see publications for more details). It is also important that SE winds are screened from the flux data (see Cook et al, 2004 for details). Propane generator power.

  17. An equivalent circuit model and power calculations for the APS SPX crab cavities.

    SciTech Connect (OSTI)

    Berenc, T. )

    2012-03-21

    An equivalent parallel resistor-inductor-capacitor (RLC) circuit with beam loading for a polarized TM110 dipole-mode cavity is developed and minimum radio-frequency (rf) generator requirements are calculated for the Advanced Photon Source (APS) short-pulse x-ray (SPX) superconducting rf (SRF) crab cavities. A beam-loaded circuit model for polarized TM110 mode crab cavities was derived. The single-cavity minimum steady-state required generator power has been determined for the APS SPX crab cavities for a storage ring current of 200mA DC current as a function of external Q for various vertical offsets including beam tilt and uncontrollable detuning. Calculations to aid machine protection considerations were given.

  18. Single pass electron beam cooling of gold ions between EBIS LINAC and booster is theoretically possible!

    SciTech Connect (OSTI)

    Hershcovitch, A.

    2011-01-01

    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. Many issues, regarding a low energy high current electron beam that is needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, were examined. Computations and some experimental data indicate that none of these issues is a show stopper. Preliminary calculations indicate that single pass cooling is feasible; momentum spread can be reduced by more than an order of magnitude in about one meter. Hence, this option cooling deserves further more serious considerations.

  19. 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)

    2012-01-15

    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.

  20. Interaction of nonthermal muon beam with electron-positron-photon plasma: A thermal field theory approach

    SciTech Connect (OSTI)

    Noorian, Zainab; Eslami, Parvin; Javidan, Kurosh

    2013-11-15

    Interaction of a muon beam with hot dense QED plasma is investigated. Plasma system contains electrons and positrons with Fermi-Dirac distribution and Bose-Einstein distributed photons while the beam particles have nonthermal distribution. The energy loss of the beam particles during the interaction with plasma is calculated to complete leading order of interaction in terms of the QED coupling constant using thermal field theory approach. The screening effects of the plasma are computed consistently using resummation of perturbation theory with hard thermal loop approximation according to the Braaten-Pisarski method. Time evolution of the plasma characteristics and also plasma identifications during the interaction are investigated. Effects of the nonthermal parameter of the beam distribution on the energy exchange and the evolution of plasma-beam system are also explained.