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1

Testing and Final Construction of the Superconducting Magnet for the Alpha Magnetic Spectrometer  

E-Print Network (OSTI)

The Alpha Magnetic Spectrometer (AMS) is a particle physics experiment based on the International Space Station (ISS). At the heart of the detector is a large superconducting magnet, cooled to a temperature of 1.8 K by ...

Harrison, Stephen

2

First Result from the Alpha Magnetic Spectrometer on the International Space Station: Precision Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5–350 GeV  

E-Print Network (OSTI)

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8×10[superscript 6] positron ...

Basil, A.

3

Associated Particle Tagging (APT) in Magnetic Spectrometers  

SciTech Connect

Summary In Brief The Associated Particle Tagging (APT) project, a collaboration of Pacific Northwest National Laboratory (PNNL), Idaho National Laboratory (INL) and the Idaho State University (ISU)/Idaho Accelerator Center (IAC), has completed an exploratory study to assess the role of magnetic spectrometers as the linchpin technology in next-generation tagged-neutron and tagged-photon active interrogation (AI). The computational study considered two principle concepts: (1) the application of a solenoidal alpha-particle spectrometer to a next-generation, large-emittance neutron generator for use in the associated particle imaging technique, and (2) the application of tagged photon beams to the detection of fissile material via active interrogation. In both cases, a magnetic spectrometer momentum-analyzes charged particles (in the neutron case, alpha particles accompanying neutron generation in the D-T reaction; in the tagged photon case, post-bremsstrahlung electrons) to define kinematic properties of the relevant neutral interrogation probe particle (i.e. neutron or photon). The main conclusions of the study can be briefly summarized as follows: Neutron generator: • For the solenoidal spectrometer concept, magnetic field strengths of order 1 Tesla or greater are required to keep the transverse size of the spectrometer smaller than 1 meter. The notional magnetic spectrometer design evaluated in this feasibility study uses a 5-T magnetic field and a borehole radius of 18 cm. • The design shows a potential for 4.5 Sr tagged neutron solid angle, a factor of 4.5 larger than achievable with current API neutron-generator designs. • The potential angular resolution for such a tagged neutron beam can be less than 0.5o for modest Si-detector position resolution (3 mm). Further improvement in angular resolution can be made by using Si-detectors with better position resolution. • The report documents several features of a notional generator design incorporating the alpha-particle spectrometer concept, and outlines challenges involved in the magnetic field design. Tagged photon interrogation: • We investigated a method for discriminating fissile from benign cargo-material response to an energy-tagged photon beam. The method relies upon coincident detection of the tagged photon and a photoneutron or photofission neutron produced in the target material. The method exploits differences in the shape of the neutron production cross section as a function of incident photon energy in order to discriminate photofission yield from photoneutrons emitted by non-fissile materials. Computational tests of the interrogation method as applied to material composition assay of a simple, multi-layer target suggest that the tagged-photon information facilitates precise (order 1% thickness uncertainty) reconstruction of the constituent thicknesses of fissile (uranium) and high-Z (Pb) constituents of the test targets in a few minutes of photon-beam exposure. We assumed an 18-MeV endpoint tagged photon beam for these simulations. • The report addresses several candidate design and data analysis issues for beamline infrastructure required to produce a tagged photon beam in a notional AI-dedicated facility, including the accelerator and tagging spectrometer.

Jordan, David V.; Baciak, James E.; Stave, Sean C.; Chichester, David; Dale, Daniel; Kim, Yujong; Harmon, Frank

2012-10-16T23:59:59.000Z

4

A new method of alpha ray measurement using a Quadrupole Mass Spectrometer  

E-Print Network (OSTI)

We propose a new method of alpha($\\alpha$)-ray measurement that detects helium atoms with a Quadrupole Mass Spectrometer(QMS). A demonstration is undertaken with a plastic-covered $^{241}$Am $\\alpha$-emitting source to detect $\\alpha$-rays stopped in the capsule. We successfully detect helium atoms that diffuse out of the capsule by accumulating them for one to 20 hours in a closed chamber. The detected amount is found to be proportional to the accumulation time. Our method is applicable to probe $\\alpha$-emitting radioactivity in bulk material.

Y. Iwata; Y. Inoue; M. Minowa

2007-04-16T23:59:59.000Z

5

Automated multispectra alpha spectrometer and data reduction system  

SciTech Connect

A complete hardware and software package for the accumulation and rapid analysis of multiple alpha pulse height spectra has been developed. The system utilizes a 4096-channel analyzer capable of accepting up to sixteen inputs from solid-state surface barrier detectors via mixer-router modules. The analyzer is interfaced to a desk-top programmable calculator and thermal line printer. A chained software package including spectrum printout, peak analysis, plutonium- 238 and plutonium-239 data reduction, and automatic energy calibration routines was written. With the chained program a complete printout, peak analysis, and plutonium data reduction of a 512-channel alpha spectrum are obtained in about three minutes with an accuracy within five percent of hand analyses. (auth)

Hochel, R.C.

1975-12-01T23:59:59.000Z

6

Performance of a short 'magnetic bottle' electron spectrometer  

Science Conference Proceedings (OSTI)

In this article, a newly constructed electron spectrometer of the magnetic bottle type is described. The instrument is part of an apparatus for measuring the electron spectra of free clusters using synchrotron radiation. Argon and helium outer valence photoelectron spectra have been recorded in order to investigate the characteristic features of the spectrometer. The energy resolution (E/{Delta}E) has been found to be {approx}30. Using electrostatic retardation of the electrons, it can be increased to at least 110. The transmission as a function of kinetic energy is flat, and is not impaired much by retardation with up to 80% of the initial kinetic energy. We have measured a detection efficiency of most probably 0.6{sub -0.1}{sup +0.05}, but at least of 0.4. Results from testing the alignment of the magnet, and from trajectory simulations, are also discussed.

Mucke, M.; Lischke, T.; Arion, T. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Foerstel, M. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Bradshaw, A. M. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany); Hergenhahn, U. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstr. 1, 17491 Greifswald (Germany)

2012-06-15T23:59:59.000Z

7

Calibration of a Thomson parabola ion spectrometer and Fujifilm imaging plate detectors for protons, deuterons, and alpha particles  

SciTech Connect

A Thomson parabola ion spectrometer has been designed for use at the Multiterawatt (MTW) laser facility at the Laboratory for Laser Energetics (LLE) at University of Rochester. This device uses parallel electric and magnetic fields to deflect particles of a given mass-to-charge ratio onto parabolic curves on the detector plane. Once calibrated, the position of the ions on the detector plane can be used to determine the particle energy. The position dispersion of both the electric and magnetic fields of the Thomson parabola was measured using monoenergetic proton and alpha particle beams from the SUNY Geneseo 1.7 MV tandem Pelletron accelerator. The sensitivity of Fujifilm BAS-TR imaging plates, used as a detector in the Thomson parabola, was also measured as a function of the incident particle energy over the range from 0.6 MeV to 3.4 MeV for protons and deuterons and from 0.9 MeV to 5.4 MeV for alpha particles. The device was used to measure the energy spectrum of laser-produced protons at MTW.

Freeman, C. G.; Canfield, M. J.; Graeper, G. B.; Lombardo, A. T.; Stillman, C. R.; Padalino, S. J. [Physics Department, SUNY Geneseo, Geneseo, New York 14454 (United States); Fiksel, G.; Stoeckl, C.; Mileham, C.; Sangster, T. C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Sinenian, N.; Frenje, J. A. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-07-15T23:59:59.000Z

8

A 4. pi. tracking TPC magnetic spectrometer for RHIC  

Science Conference Proceedings (OSTI)

The primary physics objective of the 4{pi} TPC magnetic spectrometer proposal is to search for the Quark-Gluon Plasma. In previous workshops we have discussed what the possible hadronic signatures of such a state of matter would be. Succinctly, the QGP is a direct prediction of non-perturbative QCD. Therefore the question of the existence of this new state of matter bears directly on the validity of non-perturbative QCD. However, since non-perturbative QCD has never been established, it is apparent that what may await us is a host of new phenomena that will go beyond the standard model.

Danby, G.; Eiseman, S.E.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Saulys, A.C.; Van Dijk, J.H. (Brookhaven National Lab., Upton, NY (USA)); Lindenbaum, S.J. (Brookhaven National Lab., Upton, NY (USA) City Coll., New York, NY (USA)); Chan, C.S.; Kramer, M.A.; Zhao, K. (City Coll., New York, NY (USA)); Biswas, N.; Kenney, P.; Piekarz, J. (Notre Dame Univ

1990-01-01T23:59:59.000Z

9

A HIGH-RESOLUTION HIGH-LUMINOSITY BETA-RAY SPECTROMETER DESIGN EMPLOYING AZIMUTHALLY VARYING MAGNETIC FIELDS  

E-Print Network (OSTI)

BETA-RAY SPECTROMETER DESIGN EMPLOYING AZIMUTHALLY VARYING MAGNETIC FIELDSBETA-RAY SPECTROMETER DESIGN EMPLOYING AZIMUTHALLY VARYING MAGNETIC FIELDSfield of the present type. UCRL-16802 Introduction In attempting to find an efficient magnetic beta-

Bergkvist, Karl-Erik

2008-01-01T23:59:59.000Z

10

PROBING PRIMORDIAL MAGNETIC FIELDS USING Ly{alpha} CLOUDS  

SciTech Connect

From previous studies of the effect of primordial magnetic fields on early structure formation, we know that the presence of primordial magnetic fields during early structure formation could induce more perturbations at small scales (at present 1-10 h {sup -1} Mpc) as compared to the usual {Lambda}CDM theory. Matter power spectra over these scales are effectively probed by cosmological observables such as shear correlation and Ly{alpha} clouds. In this paper we discuss the implications of primordial magnetic fields on the distribution of Ly{alpha} clouds. We simulate the line-of-sight density fluctuation including the contribution coming from the primordial magnetic fields. We compute the evolution of Ly{alpha} opacity for this case and compare our theoretical estimates of Ly{alpha} opacity with the existing data to constrain the parameters of the primordial magnetic fields. We also discuss the case when the two density fields are correlated. Our analysis yields an upper bound of roughly 0.3-0.6 nG on the magnetic field strength for a range of nearly scale-invariant models, corresponding to a magnetic field power spectrum index n {approx_equal} -3.

Pandey, Kanhaiya L.; Sethi, Shiv K. [Raman Research Institute, Bangalore 560080 (India)] [Raman Research Institute, Bangalore 560080 (India)

2013-01-01T23:59:59.000Z

11

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents (OSTI)

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

Fan, Non Q. (San Diego, CA); Clarke, John (Berkeley, CA)

1993-01-01T23:59:59.000Z

12

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers  

DOE Patents (OSTI)

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced. 7 figures.

Fan, N.Q.; Clarke, J.

1993-10-19T23:59:59.000Z

13

What Caused the Lead burn-out in Spectrometer Magnet 2B  

SciTech Connect

The spectrometer solenoids are supposed to be the first magnets installed in the MICE Cooling Channel. The results of the test of Spectrometer Magnet 2B are reported in a previous MICE Note. Magnet 2B was tested with all five coils connected in series. The magnet failed because a lead to coil M2 failed before it could be trained to its full design current of 275 A. First, this report describes the condition of the magnet when the lead failure occurred. The lead that failed was between the cold mass feed-through and the heavy lead that connected to coil M2 and the quench protection diodes. It is believed that the lead failed because the minimum propagation zone (MPZ) length was too short. The quench was probably triggered by lead motion in the field external to the magnet center coil. The effect of heat transfer on quench propagation and MPZ length is discussed. The MPZ length is compared for a number of cases that apply to the spectrometer solenoid 2B as built and as it has been repaired. The required heat transfer coefficient for cryogenic stability and the quench propagation velocity along the leads are compared for various parts of the Magnet leads inside the cold mass cryostat. The effect of the insulation on leads on heat transfer is and stability is discussed.

Green, Michael A

2010-11-29T23:59:59.000Z

14

MFTF-. cap alpha. +T end plug magnet design  

SciTech Connect

The conceptual design of the end-plug magnets for MFTF-..cap alpha..+T is described. MFTF-..cap alpha..+ T is a near-term upgrade of MFTF-B, which features new end plugs to improve performance. The Fusion Engineering Design Center has performed the engineering design of MFTF-..cap alpha..+T under the overall direction of Lawrence Livermore National Laboratory. Each end plug consists of two Yin-Yang pairs, each with approx.2.5:1 mirror ratio and approx.5-T peak field on axis; two transition coils; and a recircularizing solenoid. This paper describes the end-plug magnet system functional requirements and presents a conceptual design that meets them. The peak field at the windings of the end-plug coils is approx.6-T. These coils are designed using the NbTi MFTF-B conductor and cooled by a 4.2K liquid helium bath. All the end-plug magnets are designed to operate in the cryostable mode with adequate quench protection for safety. Shielding requirements are stated and a summary of heat loads is provided. Field and force calculations are discussed. The field on axis is shown to meet the functional requirements. Force resultants are reported in terms of winding running loads and resultant coil forces are also given. The magnet structural support is described. A trade study to determine the optimum end-cell coil internal nuclear shield thickness and the resulting coil size based on minimizing the end-cell life cycle cost is summarized.

Srivastava, V.C.; O'Toole, J.A.

1983-01-01T23:59:59.000Z

15

A Bayesian Method for Identifying Contaminated Detectors in Low-Level Alpha Spectrometers  

SciTech Connect

Analyses used for radiobioassay and other radiochemical tests are normally designed to meet specified quality objectives, such relative bias, precision, and minimum detectable activity (MDA). In the case of radiobioassay analyses for alpha emitting radionuclides, a major determiner of the process MDA is the instrument background. Alpha spectrometry detectors are often restricted to only a few counts over multi-day periods in order to meet required MDAs for nuclides such as plutonium-239 and americium-241. A detector background criterion is often set empirically based on experience, or frequentist or classical statistics are applied to the calculated background count necessary to meet a required MDA. An acceptance criterion for the detector background is set at the multiple of the estimated background standard deviation above the assumed mean that provides an acceptably small probability of observation if the mean and standard deviation estimate are correct. The major problem with this method is that the observed background counts used to estimate the mean, and thereby the standard deviation when a Poisson distribution is assumed, are often in the range of zero to three counts. At those expected count levels it is impossible to obtain a good estimate of the true mean from a single measurement. As an alternative, Bayesian statistical methods allow calculation of the expected detector background count distribution based on historical counts from new, uncontaminated detectors. This distribution can then be used to identify detectors showing an increased probability of contamination. The effect of varying the assumed range of background counts (i.e., the prior probability distribution) from new, uncontaminated detectors will be is discussed.

Maclellan, Jay A.; Strom, Daniel J.; Joyce, Kevin E.

2011-11-02T23:59:59.000Z

16

Detection of alpha radiation in a beta radiation field  

DOE Patents (OSTI)

An apparatus and method for detecting alpha particles in the presence of high activities of beta particles utilizing an alpha spectrometer. The apparatus of the present invention utilizes a magnetic field applied around the sample in an alpha spectrometer to deflect the beta particles from the sample prior to reaching the detector, thus permitting detection of low concentrations of alpha particles. In the method of the invention, the strength of magnetic field required to adequately deflect the beta particles and permit alpha particle detection is given by an algorithm that controls the field strength as a function of sample beta energy and the distance of the sample to the detector.

Mohagheghi, Amir H. (Albuquerque, NM); Reese, Robert P. (Edgewood, NM)

2001-01-01T23:59:59.000Z

17

Spectrometer sensitivity calibration in the extreme uv by means of branching ratios of magnetic dipole lines  

SciTech Connect

Relative intensity measurements of various line pairs resulting from magnetic dipole transitions within the configurations s/sup 2/p/sup 2/ and s/sup 2/p/sup 4/, in conjunction with calculated transition probabilities, have been used to determine the wavelength dependence of the sensitivity of a grazing incidence spectrometer, in the range 400 to 1000 A. Emissions from Cr XIX, Fe XXI, Ni XXI and XXIII, Cu XXIV, and Zr XXVII ions in PLT tokamak discharges were used for this purpose. Absolute sensitivity of the spectrometer at selected wavelengths had been determined by the traditional hydrogen, helium, carbon, and oxygen electric-dipole line pairs from the same discharges. Similar attempts to use transitions in the s/sup 2/p/sup 3/ configurations in Cr XVIII, Zr XXVI, and Mo XXVIII ions resulted in significant discrepancies that are ascribed to uncertainties in the corresponding calculated transition probabilities.

Denne, B.; Hinnov, E.

1984-04-01T23:59:59.000Z

18

Samuel C.C. Ting, the J/psi Particle (Charm), and the Alpha Magnetic  

Office of Scientific and Technical Information (OSTI)

Samuel C.C. Ting, the J/psi Particle (Charm), and Samuel C.C. Ting, the J/psi Particle (Charm), and the Alpha Magnetic Spectrometer (AMS) Resources with Additional Information Samuel C.C. Ting Credit: Courtesy of the Massachusetts Institute of Technology 'Samuel C.C. Ting was born ... in Ann Arbor, Michigan, ... [and] received his elementary and secondary education in China ... . He excelled in mathematics, science and history. In 1956, Ting returned to the United States to attend the University of Michigan as an engineering student, but he soon transferred his major to physics.'1 In 1959, he was awarded a BSE (in physics) and BSE (in mathematics), both from the University of Michigan and in 1962, he was awarded a Ph.D. (in physics), also from the University of Michigan. 'After receiving his Ph.D., Ting went to CERN as a Ford Foundation postdoctoral scholar, then joined the faculty at Columbia University where he became interested in the physics of electron-positron pair production. ...

19

Methyl quantum tunneling and nitrogen-14 NQR NMR studies using a SQUID magnetic resonance spectrometer  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) techniques have been very successful in obtaining molecular conformation and dynamics information. Unfortunately, standard NMR and NQR spectrometers are unable to adequately detect resonances below a few megahertz due to the frequency dependent sensitivity of their Faraday coil detectors. For this reason a new spectrometer with a dc SQUID (Superconducting Quantum Interference Device) detector, which has no such frequency dependence, has been developed. Previously, this spectrometer was used to observe {sup 11}B and {sup 27}Al NQR resonances. The scope of this study was increased to include {sup 23}Na, {sup 51}V, and {sup 55}Mn NQR transitions. Also, a technique was presented to observe {sup 14}N NQR resonances through cross relaxation of the nitrogen polarization to adjacent proton spins. When the proton Zeeman splitting matches one nitrogen quadrupoler transition the remaining two {sup 14}N transitions can be detected by sweeping a saturating rf field through resonance. Additionally, simultaneous excitation of two nitrogen resonances provides signal enhancement which helps to connect transitions from the same site. In this way, nitrogen-14 resonances were observed in several amino acids and polypeptides. This spectrometer has also been useful in the direct detection of methyl quantum tunneling splittings at 4.2 K. Tunneling, frequencies of a homologous series of carboxylic acids were measured and for solids with equivalent crystal structures, an exponential correlation between the tunneling frequency and the enthalpy of fusion is observed. This correlation provides information about the contribution of intermolecular interactions to the energy barrier for methyl rotation.

Black, B.E. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States)

1993-07-01T23:59:59.000Z

20

Measuring the absolute DT neutron yield using the Magnetic Recoil Spectrometer at OMEGA and the NIF  

SciTech Connect

A Magnetic Recoil Spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion (ICF) implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

Mackinnon, A; Casey, D; Frenje, J A; Johnson, M G; Seguin, F H; Li, C K; Petrasso, R D; Glebov, V Y; Katz, J; Knauer, J; Meyerhofer, D; Sangster, T; Bionta, R; Bleuel, D; Hachett, S P; Hartouni, E; Lepape, S; Mckernan, M; Moran, M; Yeamans, C

2012-05-03T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF  

SciTech Connect

The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Glebov, V. Yu.; Katz, J.; Magoon, J.; Meyerhofer, D. D.; Sangster, T. C.; Shoup, M.; Ulreich, J. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Ashabranner, R. C.; Bionta, R. M.; Carpenter, A. C.; Felker, B.; Khater, H. Y.; LePape, S.; MacKinnon, A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

2013-04-15T23:59:59.000Z

22

Magnetic Fields1 Increasingly, instruments that generate large static magnetic fields (e.g., NMR spectrometers,  

E-Print Network (OSTI)

been issued by the International Commission on Non-ionizing Radiation (ICNIRP, 2009), which internal shielding, which reduces the strength of the magnetic field outside of the instrument. Strong, the hazards associated with cryogenic liquids are of concern, as well. The health effects of exposure

Shull, Kenneth R.

23

Effect of milling time on magnetic properties and structures of bulk Sm-Co/{alpha}-(Fe, Co) nanocomposite magnets  

Science Conference Proceedings (OSTI)

Bulk Sm-Co/{alpha}-(Fe,Co) nanocomposite magnets were fabricated by hot pressing composite powders prepared by high-energy ball milling of magnetically hard SmCo{sub 5} powder and magnetically soft Fe powder. The bulk magnets had a nanocomposite structure consisting of Sm-Co matrix (1:5 H and 1:7 H phases) and {alpha}-(Fe,Co) phases. The Fe-Co particles were distributed uniformly in the Sm-Co matrix. The milling time strongly affects the structures and the magnetic properties of the bulk magnets. Increasing milling time led to a decrease of the amount of 1:5 H phase, an increase in the phase fraction of the 1:7 H phase, and a decrease in the amount of soft phase, which resulted in an increase in magnetization and a decrease in coercivity. Scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) analyses revealed that inter-diffusion took place between the Sm-Co matrix and Fe particles during the processing.

Shen, Y. [UDRI, University of Dayton, Dayton, Ohio 45469 (United States); AFRL, Wright-Patterson Air Force Base, Ohio 45433 (United States); Huang, M. Q.; Turgut, Z. [AFRL, Wright-Patterson Air Force Base, Ohio 45433 (United States); UES Inc., Dayton, Ohio 45432 (United States); Lucas, M. S. [AFRL, Wright-Patterson Air Force Base, Ohio 45433 (United States); UTC, Dayton, Ohio 45432 (United States); Michel, E. [AFRL, Wright-Patterson Air Force Base, Ohio 45433 (United States); Wright State University, Dayton, Ohio 45435 (United States); Horwath, J. C. [AFRL, Wright-Patterson Air Force Base, Ohio 45433 (United States)

2012-04-01T23:59:59.000Z

24

The Superconducting Horizontal Bend Magnet for the Jefferson Lab's 11 GeV/c Super High Momentum Spectrometer  

SciTech Connect

A collaboration between NSCL and Jlab has developed the reference design and coil winding for Jlab's Super High Momentum Spectrometer (SHMS) horizontal bend magnet. A warm iron ??C?? type superferric dipole magnet will bend the 12 GeV/c particles horizontally by 3?? to allow the SHMS to reach angles as low as 5.5??. This requires an integral field strength of up to 2.1 T.m. The major challenges are the tight geometry, high and unbalanced forces and a required low fringe field in primary beam path. A coil design based on flattened SSC Rutherford cable that provides a large current margin and commercially available fiberglass prepreg epoxy tape has been developed. A complete test coil has been wound and will be cold tested. This paper present the modified magnet design includes coil forces, coil restraint system and fringe field. In addition, coil properties, quench calculations and the full mechanical details are also presented.

S. Chouhan, J. DeKamp, A. Zeller, P. Brindza, S. Lassiter, M. Fowler, E. Sun

2010-06-01T23:59:59.000Z

25

Measuring the absolute deuteriumtritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF  

E-Print Network (OSTI)

neutron spectrometer at ASDEX Upgrade Rev. Sci. Instrum. 82, 123504 (2011) The new cold neutron chopper. Paguio8 1 Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139, USA 2 Laboratory confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion

26

Measuring the absolute deuterium-tritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF  

SciTech Connect

A magnetic recoil spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139 (United States); Glebov, V. Yu.; Katz, J.; Knauer, J. P.; Meyerhofer, D. D.; Sangster, T. C. [Laboratory for Laser Energetics, UR, Rochester, New York 14623 (United States); Bionta, R. M.; Bleuel, D. L.; Doeppner, T.; Glenzer, S.; Hartouni, E.; Hatchett, S. P.; Le Pape, S.; Ma, T.; MacKinnon, A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

2012-10-15T23:59:59.000Z

27

Study of the 30P({alpha},p){sup 33}S reaction using a gas-filled magnetic spectrograph  

Science Conference Proceedings (OSTI)

We have developed a technique using a gas-filled magnetic spectrograph which enables us to study ({alpha},p) transfer reactions of astrophysical interest in inverse kinematics and by means of the time-inverse reactions. We present preliminary experimental results of the reaction {sup 30}P({alpha},p){sup 33}S which confirm that the technique permits the study of these kinds of transfer reactions.

Figueira, J. M. [Laboratorio TANDAR, Comision Nacional de Energia Atomica, B1650KNA San Martin, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, C1033AAJ Buenos Aires (Argentina); Deibel, C. M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States); Fernandez Niello, J. O. [Laboratorio TANDAR, Comision Nacional de Energia Atomica, B1650KNA San Martin, Buenos Aires (Argentina); Universidad Nacional de General SanMartin, B1650BWA SanMartin, Buenos Aires (Argentina); Greene, J.; Jiang, C. L.; Lee, H. Y.; Pardo, R. C.; Rehm, K. E.; Ugalde, C.; Zinkann, G. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Marley, S. T. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Physics Department, Western Michigan University, Kalamazoo, MI 49008 (United States); Patel, N. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Department of Physics, Colorado School of Mines, Golden, CO 80401 (United States); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem (Israel)

2010-08-04T23:59:59.000Z

28

High-efficiency cross-beam magnetic electron-impact source for improved miniature Mattauch-Herzog mass spectrometer performance  

Science Conference Proceedings (OSTI)

We describe a newly designed cross-beam magnetic electron-impact ion source (CBM-EI). We demonstrate its superiority in comparison with a conventional source (CB-EI) when used with a commercial miniature sector-field-type, non-scanning mass spectrometer featuring Mattauch-Herzog geometry (MH-MS) and a permanent sector-field magnet. This paper clearly shows the value of the CBM-EI for enhancing MH-MS sensitivity. Unlike secondary electron-multiplier type detectors, the pixelated detector (IonCCD Trade-Mark-Sign ) used in the commercial MH-MS has no gain. The MH-MS/IonCCD system is therefore challenged to compete with time-of-flight and quadrupole MS systems due to their higher ion transmissions and detector gains. Using the new CBM-EI, we demonstrate an instrument sensitivity increase of 20-fold to 100-fold relative to the CB-EI-equipped instrument. This remarkable signal increase by the simple addition of the magnet assembly arises from the magnet-induced gyromotion of the thermionic electrons, which vastly increases the effective path length of the electrons through the ionization region, and the collimated nature of the electron flux, which optimizes the ion transmission through the 100-{mu}m object slit of the MH-MS. Some or all of the realized sensitivity increase may be exchanged for an increase in resolution and/or mass range through the use of a narrower object slit, or for a reduction in ion-source pressure to limit quenching. The CBM-EI should facilitate development of a differentially pumped ion source to extend the lifetime of the filament, especially in otherwise intractable applications associated with oxidizing and corrosive samples.

Hadjar, O.; Fowler, W. K. [OI Analytical/CMS Field Products, 2148 Pelham Parkway, Bldg. 400, Pelham, Alabama 35124 (United States)

2012-06-15T23:59:59.000Z

29

Nuclear magnetic flowmeter -- Spectrometer with fiber -optical communication line in cooling systems of atomic energy plants  

Science Conference Proceedings (OSTI)

Fiber-optic communication line for transmitting a signal of nuclear magnetic resonance of liquid medium in the ship's central computer was developed. This fiber-optic communication line allows us to give an NMR signal in digital or analog form without ... Keywords: FOCL transmission coefficient, Fiber optic communication line (FOCL), communication system, optical converter, optical modulator

V. V. Davydov; V. I. Dudkin; A. U. Karseev

2013-04-01T23:59:59.000Z

30

Nuclear Magnetic Resonance Laboratory  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance Laboratory. ... A 600 MHz Nuclear Magnetic Resonance Spectrometer. Analytical Data Compilation Reference Materials. ...

2012-10-01T23:59:59.000Z

31

Direct current superconducting quantum interference device spectrometer for pulsed nuclear magnetic resonance and nuclear quadrupole resonance at frequencies up to 5 MHz  

Science Conference Proceedings (OSTI)

A spectrometer based on a dc superconducting quantum interference device (SQUID) has been developed for the direct detection of nuclear magnetic resonance (NMR) or nuclear quadrupole resonance (NQR) at frequencies up to 5 MHz. The sample is coupled to the input coil of the niobium-based SQUID via a nonresonant superconducting circuit. The flux locked loop involves the direct offset integration technique with additional positive feedback in which the output of the SQUID is coupled directly to a low-noise preamplifier. Precession of the nuclear quadrupole spins is induced by a magnetic field pulse with the feedback circuit disabled; subsequently, flux locked operation is restored and the SQUID amplifies the signal produced by the nuclear free induction signal. The spectrometer has been used to detect {sup 27}Al NQR signals in ruby (Al{sub 2}O{sub 3}[Cr{sup 3+}]) at 359 and 714 kHz. {copyright} {ital 1996 American Institute of Physics.}

TonThat, D.M.; Clarke, J. [Department of Physics, University of , California (United States)]|[Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

1996-08-01T23:59:59.000Z

32

Monolithic spectrometer  

DOE Patents (OSTI)

A monolithic spectrometer is disclosed for use in spectroscopy. The spectrometer is a single body of translucent material with positioned surfaces for the transmission, reflection and spectral analysis of light rays.

Rajic, Slobodan (Knoxville, TN); Egert, Charles M. (Oak Ridge, TN); Kahl, William K. (Knoxville, TN); Snyder, Jr., William B. (Knoxville, TN); Evans, III, Boyd M. (Oak Ridge, TN); Marlar, Troy A. (Knoxville, TN); Cunningham, Joseph P. (Oak Ridge, TN)

1998-01-01T23:59:59.000Z

33

High magnetic shear gain in a liquid sodium stable couette flow experiment A prelude to an alpha - omega dynamo  

Science Conference Proceedings (OSTI)

The {Omega}-phase of the liquid sodium {alpha}-{Omega} dynamo experiment at NMIMT in cooperation with LANL has successfully demonstrated the production of a high toroidal field, B{sub {phi}} {approx_equal} 8 x B{sub r} from the radial component of an applied poloidal magnetic field, B{sub r}. This enhanced toroidal field is produced by rotational shear in stable Couette Row within liquid sodium at Rm {approx_equal} 120. The small turbulence in stable Taylor-Couette Row is caused by Ekman Row where ({delta}v/v){sup 2} {approx} 10{sup -3}. This high {Omega}-gain in low turbulence flow contrasts with a smaller {Omega}-gain in higher turbulence, Helmholtz-unstable shear flows. This result supports the ansatz that large scale astrophysical magnetic fields are created within semi-coherent large scale motions in which turbulence plays a diffusive role that enables magnetic flux linkage.

Colgate, Stirling [Los Alamos National Laboratory; Li, Jui [Los Alamos National Laboratory; Finn, John [Los Alamos National Laboratory; Pariev, Vladimir [Los Alamos National Laboratory; Beckley, Howard [NM INSTIT. OF MINING AND TECH; Si, Jiahe [NM INSTIT. OF MINING AND TECH.; Martinic, Joe [NM INSTIT. OF MINING AND TECH.; Westpfahl, David [NM INSTIT. OF TECH.; Slutz, James [NM INSTIT. OF MINING AND TECH.; Westrom, Zeb [NM INSTIT. OF TECH.; Klein, Brianna [NM INSTIT. OF MINING AND TECH.

2010-11-08T23:59:59.000Z

34

Direct Determination of the Magnetic Quadrupole Contribution to the Lyman-{alpha}{sub 1} Transition in a Hydrogenlike Ion  

Science Conference Proceedings (OSTI)

We report the observation of an interference between the electric dipole (E1) and the magnetic quadrupole (M2) amplitudes for the linear polarization of the Ly-{alpha}{sub 1} (2p{sub 3/2}{yields}1s{sub 1/2}) radiation of hydrogenlike uranium. This multipole mixing arises from the coupling of the ion to different multipole components of the radiation field. Our observation indicates a significant depolarization of the Ly-{alpha}{sub 1} radiation due to the E1-M2 amplitude mixing. It proves that a combined measurement of the linear polarization and of the angular distribution enables a very precise determination of the ratio of the E1 and the M2 transition amplitudes and the corresponding transition rates without any assumptions concerning the population mechanism for the 2p{sub 3/2} state.

Weber, G.; Stoehlker, Th. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Physikalisches Institut, Universitaet Heidelberg, 69120 Heidelberg (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany); Braeuning, H.; Hess, S.; Kozhuharov, C.; Spillmann, U. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Surzhykov, A.; Maertin, R.; Winters, D. F. A. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Physikalisches Institut, Universitaet Heidelberg, 69120 Heidelberg (Germany); Brandau, C. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Institut fuer Atom- und Molekuelphysik, Justus-Liebig-Universitaet, 35392 Giessen (Germany); Fritzsche, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); FIAS Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany); Department of Physics, University of Oulu, 90014 Oulu (Finland); Geyer, S. [Institut fuer Angewandte Physik, Universitaet Frankfurt, 60438 Frankfurt am Main (Germany); Hagmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Institut fuer Kernphysik, Universitaet Frankfurt, 60438 Frankfurt am Main (Germany); Petridis, N. [Institut fuer Kernphysik, Universitaet Frankfurt, 60438 Frankfurt am Main (Germany); Reuschl, R. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); FIAS Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany); ExtreMe Matter Institute EMMI, 64291 Darmstadt (Germany); Trotsenko, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany)

2010-12-10T23:59:59.000Z

35

Multidimensional spectrometer  

DOE Patents (OSTI)

A multidimensional spectrometer for the infrared, visible, and ultraviolet regions of the electromagnetic spectrum, and a method for making multidimensional spectroscopic measurements in the infrared, visible, and ultraviolet regions of the electromagnetic spectrum. The multidimensional spectrometer facilitates measurements of inter- and intra-molecular interactions.

Zanni, Martin Thomas (Madison, WI); Damrauer, Niels H. (Boulder, CO)

2010-07-20T23:59:59.000Z

36

High temperature magnetic properties of SmCo{sub 5}/{alpha}-Fe(Co) bulk nanocomposite magnets  

SciTech Connect

To find alternative high temperature magnets containing no heavy rare earths for power applications, SmCo{sub 5}/Fe bulk nanocomposite magnets with enhanced energy density and high thermal stability have been produced by using a ball-milling plus warm-compaction route. Up to 30% of the Fe soft magnetic phase has been added to the composites with grain size <20 nm distributed homogenously in the matrix of the SmCo{sub 5} hard magnetic phase. It was observed that the microstructure does not change with temperature up to 500 Degree-Sign C. It is also observed that the thermal stability of bulk nanocomposite samples is closely related to bulk density. Energy products above 11 MGOe have been obtained at 300 Degree-Sign C in fully dense bulk SmCo{sub 5}/Fe nanocomposite magnets, which is 65% higher than that of a single-phase counterpart at the same temperature.

Rong Chuanbing; Poudyal, Narayan; Liu, X. B.; Ping Liu, J. [Department of Physics, University of Texas at Arlington, Arlington, Texas 76019 (United States); Zhang Ying [Department of Physics, University of Texas at Arlington, Arlington, Texas 76019 (United States); Division of Materials Science and Engineering, Ames Laboratory, USDOE, Iowa State University, Ames, Iowa 50011 (United States); Kramer, M. J. [Division of Materials Science and Engineering, Ames Laboratory, USDOE, Iowa State University, Ames, Iowa 50011 (United States)

2012-10-08T23:59:59.000Z

37

Convergence Studies of Thermal and Electromagnetic Transient Quench Analysis of 11 GeV Super High Momentum Spectrometer Superconducting Magnets in Jefferson Lab  

Science Conference Proceedings (OSTI)

This paper presents results of convergence studies of transient thermal and electromagnetic quench analysis of five Super High Momentum Spectrometer (SHMS) superconducting magnets: HB, Q1, Q2, Q3, and Dipole, using Vector Fields Quench analysis codes. The convergence of the hot spot temperature and solution solve times were used to investigate the effects of element types, mesh densities, and tolerance criteria. The comparisons between tetrahedral elements and hexahedral elements was studied, and their advantages and disadvantages were discussed. Based on the results of convergence studies, a meshing guideline for coils is presented. The impact of iteration tolerance to the hot spot temperature was also explored, and it is found that tight tolerances result in extremely long solve times with only marginal improvements in the results.

Eric Sun, Paul Brindza, Steve Lassiter, Mike Fowler, E. Xu

2010-11-01T23:59:59.000Z

38

Spectrometer gun  

SciTech Connect

A hand-holdable, battery-operated, microprocessor-based spectrometer gun includes a low-power matrix display and sufficient memory to permit both real-time observation and extended analysis of detected radiation pulses. Universality of the incorporated signal processing circuitry permits operation with various detectors having differing pulse detection and sensitivity parameters.

Waechter, David A. (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM); Umbarger, C. John (Los Alamos, NM)

1985-01-01T23:59:59.000Z

39

Spectrometer gun  

DOE Patents (OSTI)

A hand-holdable, battery-operated, microprocessor-based spectrometer gun is described that includes a low-power matrix display and sufficient memory to permit both real-time observation and extended analysis of detected radiation pulses. Universality of the incorporated signal processing circuitry permits operation with various detectors having differing pulse detection and sensitivity parameters.

Waechter, D.A.; Wolf, M.A.; Umbarger, C.J.

1981-11-03T23:59:59.000Z

40

Cryogenic system design of 11 GEV/C super high momentum spectrometer superconducting magnets at Jefferson Lab  

SciTech Connect

The design of the cryogenic system for the 11 GeV/c Super High Momentum Spectrometer (SHMS) is presented. A description of the cryogenic control reservoir and the cryogenic transfer line is given. Details of the cryogenic control reservoirs, cryogenic transfer lines, and pressure piping are summarized. Code compliance is ensured through following the requirements of the ASME Pressure Vessel Code and Pressure Piping Code. An elastic-plastic-analysis-based combined safety factor approach is proposed to meet the low stress requirement of ASME 2007 Section VIII, Division 2 so that Charpy V-notch (CVN) impact testing can be avoided through analysis. Material toughness requirements in ASME 2007 Section VIII, Division 2 are adopted as CVN impact testing rules of stainless steel 304 piping at 4.2 K and 77 K. A formula-based combined safety factor approach for pressure piping is also proposed to check whether the impact testing can be avoided due to low stress. Analysis and calculation have shown that no CVN impact testing of base metal and heat affected zones is required for the helium reservoir, nitrogen reservoir, and their relevant piping. Total heat loads to liquid helium and liquid nitrogen are studied also. The total heat load to LHe for SHMS is estimated to be 137 W, and the total load to LN2 is calculated to be 420 W.

Eric Sun, Paul Brindza, Steven Lassister, Mike Fowler

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Spherical, Oscillatory $\\alpha^{2}$-Dynamo Induced by Magnetic Coupling Between a Fluid Shell and an Inner Electrically Conducting Core Relevance to the Solar Dynamo  

E-Print Network (OSTI)

A two-layer spherical $\\alpha^2$-dynamo model consisting of an innerelectrically conducting core (magnetic diffusivity $\\lambda_i$ and radius$r_i$) with $\\alpha = 0$ surrounded by an electrically conducting sphericalshell (magnetic diffusivity $\\lambda_o$ and radius $r_o$) with a constant$\\alpha$ is shown to exhibit oscillatory behavior for values of $\\beta =\\lambda_i/\\lambda_o$ and $r_i/r_o$ relevant to the solar dynamo. Time-dependentdynamo solutions require $r_i/r_o \\geq 0.55$ and $\\beta \\leq O(1)$. For theSun, $r_i/r_o$ is about 0.8 and $\\beta\\approx 10^{-3}$. The time scale of theoscillations matches the 22 year period of the sunspot cycle for $\\lambda_0 =O(10^2 km^2 s^{-1}$). It is unnecessary to hypothesize an $\\alpha\\omega$-dynamoto obtain oscillatory dynamo solutions; an $\\alpha^2$-dynamo suffices providedthe spherical shell region of dynamo action lies above a large, lessmagnetically diffusive core, as is the case for the solar dynamo.

Schubert, G

2000-01-01T23:59:59.000Z

42

Coupled Transient Finite Element Simulation of Quench in Jefferson Lab's 11 GeV Super High Momentum Spectrometer Superconducting Magnets  

Science Conference Proceedings (OSTI)

This paper presents coupled transient thermal and electromagnetic finite element analysis of quench in the Q2, Q3, and dipole superconducting magnets using Vector Fields Quench code. Detailed temperature distribution within coils and aluminum force collars were computed at each time step. Both normal (quench with dump resistor) and worst-case (quench without dump resistor) scenarios were simulated to investigate the maximum temperatures. Two simulation methods were utilized, and their algorithms, implementation, advantages, and disadvantages are discussed. The first method simulated the coil using nonlinear transient thermal analysis directly linked with the transient circuit analysis. It was faster because only the coil was meshed and no eddy current was modeled. The second method simulated the whole magnet including the coil, the force collar, and the iron yoke. It coupled thermal analysis with transient electromagnetic field analysis which modeled electromagnetic fields including eddy currents within the force collar. Since eddy currents and temperature in the force collars were calculated in various configurations, segmentation of the force collars was optimized under the condition of fast discharge.

E. Sun, P. Brindza, S. Lassiter, M. Fowler, E. Xu

2010-06-01T23:59:59.000Z

43

Glossary Term - Alpha Decay  

NLE Websites -- All DOE Office Websites (Extended Search)

Universe Previous Term (10 Most Abundant Elements in the Universe) Glossary Main Index Next Term (Alpha Particle) Alpha Particle Alpha Decay Alpha Decay Diagram Alpha decay is one...

44

HELIcal Orbit Spectrometer (HELIOS)  

NLE Websites -- All DOE Office Websites (Extended Search)

kinematics The HELIOS Spectrometer concept The Argonne implementation of HELIOS Commissioning experiment Planned upgrades Helios elsewhere B.B.Back, Argonne National Laboratory...

45

Mobile Ice Nucleus Spectrometer  

SciTech Connect

This first year report presents results from a computational fluid dynamics (CFD) study to assess the flow and temperature profiles within the mobile ice nucleus spectrometer.

Kulkarni, Gourihar R.; Kok, G. L.

2012-05-07T23:59:59.000Z

46

SNS backscattering spectrometer, BASIS  

Science Conference Proceedings (OSTI)

We describe the design and current performance of the backscattering silicon spectrometer (BASIS), a time-of-flight backscattering spectrometer built at the spallation neutron source (SNS) of the Oak Ridge National Laboratory (ORNL). BASIS is the first silicon-based backscattering spectrometer installed at a spallation neutron source. In addition to high intensity, it offers a high-energy resolution of about 3.5 {mu}eV and a large and variable energy transfer range. These ensure an excellent overlap with the dynamic ranges accessible at other inelastic spectrometers at the SNS.

Mamontov, Eugene [ORNL; Herwig, Kenneth W [ORNL

2011-01-01T23:59:59.000Z

47

Alpha Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Basics of Radiation Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements. 4. A civil defense instrument (CD V-700) cannot detect the presence of radioactive materials that produce alpha radiation unless the radioactive materials also produce beta and/or gamma radiation.

48

Microscopic evidence for a partially gapped density wave state in {alpha}-(BEDT-TTF){sub 2}KHg(SCN){sub 4} in high magnetic fields.  

Science Conference Proceedings (OSTI)

We present NMR measurements on {alpha}-(BEDt-TTF){sub 2}KHg(SCN){sub 4}, in which the six inner carbon sites of BEDT-TTF are labeled with the {sup 13}C isotope, at low temperatures and in magnetic fields up to 28.8 T. We find, based on microscopic measurements which probe the center of the primary molecular orbital, that the density wave ground state of this system persists up to fields well above the so-called 'kink field', a hysteretic transition observed in transport near 23 T below 6 K. The main implication of this result is that in the low temperature limit, the ground state of this material is not fully metallic, but still partially gapped, even to 28.8 T. We obtain a BCS-like relationship between the transition temperature and the energy gap, as derived from the spin relaxation measurements using a simple model. Further, the {sup 13}C NMR spectrum is relatively insensitive to crossing the phase boundary, a result that does not support the notion that the ground state is a conventional spin density wave ground state.

Kuhns, P. L.; Brooks, J. S.; Caldwell, T.; Moulton, W. G.; Reyes, A. P.; Biskup, N.; Kini, A. M.; Schlueter, J. A.; Wang, H. H.; Geiser, U.; Williams, J. M.; Florida State Univ.

1999-02-01T23:59:59.000Z

49

Imaging Fourier transform spectrometer  

DOE Patents (OSTI)

This invention is comprised of an imaging Fourier transform spectrometer having a Fourier transform infrared spectrometer providing a series of images to a focal plane array camera. The focal plane array camera is clocked to a multiple of zero crossing occurrences as caused by a moving mirror of the Fourier transform infrared spectrometer and as detected by a laser detector such that the frame capture rate of the focal plane array camera corresponds to a multiple of the zero crossing rate of the Fourier transform infrared spectrometer. The images are transmitted to a computer for processing such that representations of the images as viewed in the light of an arbitrary spectral ``fingerprint`` pattern can be displayed on a monitor or otherwise stored and manipulated by the computer.

Bennett, C.L.

1993-09-13T23:59:59.000Z

50

Real time Faraday spectrometer  

DOE Patents (OSTI)

This invention is comprised of a charged particle spectrometer that contains a detection system which embodies the benefits of both foil-light emissions and faraday cups, yet it does not interfere with the particle beam. 5 Figs. (GHH)

Smith, T.E. Jr.; Struve, K.W.; Colella, N.J.

1990-12-31T23:59:59.000Z

51

An Instantaneous CCN Spectrometer  

Science Conference Proceedings (OSTI)

A thermal gradient diffusion cloud chamber with a supersaturation field that increases along the path of the flow of sample is used as a cloud condensation nucleus (CCN) spectrometer. The CCN spectrum is derived from the final droplet size ...

James G. Hudson

1989-12-01T23:59:59.000Z

52

Glossary Term - Alpha Particle  

NLE Websites -- All DOE Office Websites (Extended Search)

Decay Previous Term (Alpha Decay) Glossary Main Index Next Term (Atomic Number) Atomic Number Alpha Particle alphaparticle.gif Produced during alpha decay, an alpha particle is a...

53

Broad band waveguide spectrometer  

DOE Patents (OSTI)

A spectrometer for analyzing a sample of material utilizing a broad band source of electromagnetic radiation and a detector. The spectrometer employs a waveguide possessing an entry and an exit for the electromagnetic radiation emanating from the source. The waveguide further includes a surface between the entry and exit portions which permits interaction between the electromagnetic radiation passing through the wave guide and a sample material. A tapered portion forms a part of the entry of the wave guide and couples the electromagnetic radiation emanating from the source to the waveguide. The electromagnetic radiation passing from the exit of the waveguide is captured and directed to a detector for analysis.

Goldman, Don S. (Folsom, CA)

1995-01-01T23:59:59.000Z

54

An Improved Raindrop Chemistry Spectrometer  

Science Conference Proceedings (OSTI)

A spectrometer allowing size-fractional chemical analysis of raindrops has been described previously by the authors. Modifications to this raindrop chemistry spectrometer now allow improved performance in windy conditions. Instrument ...

Stuart G. Bradley; Stephen J. Adams; C. David Stow; Stephen J. de Mora

1991-08-01T23:59:59.000Z

55

Alpha Channeling in Rotating Plasma with Stationary Waves  

SciTech Connect

An extension of the alpha channeling effect to supersonically rotating mirrors shows that the rotation itself can be driven using alpha particle energy. Alpha channeling uses radiofrequency waves to remove alpha particles collisionlessly at low energy. We show that stationary magnetic fields with high n? can be used for this purpose, and simulations show that a large fraction of the alpha energy can be converted to rotation energy.

A. Fetterman and N.J. Fisch

2010-02-15T23:59:59.000Z

56

Installation of a magnetic spectrometer on the  

E-Print Network (OSTI)

. HEDP facilities ­ The National Ignition Facility (NIF) ­ OMEGA laser 3. Known nuclear reactions used-36 cm-2 s-1) NIF OMEGA p p p d 3He p p p d 3He 4He p p 6Be ve e+ ve e+ g g Nucleosynthesis of light facilities ­ The National Ignition Facility (NIF) ­ OMEGA laser 3. Known nuclear reactions used to probe HEDP

57

What Happened with Spectrometer Magnet 2B  

E-Print Network (OSTI)

of Cold Mass at E2 End TSD1 (K) T Outside Condenser 1 TSD2 (K) T Outside Condenser 2 TSD3 (K) T Outside Condenser 3 TSD4 (K) T inside Cryostat Bottom

Green, Michael A

2010-01-01T23:59:59.000Z

58

MASS SPECTROMETER LEAK  

DOE Patents (OSTI)

An improved valve is described for precisely regulating the flow of a sample fluid to be analyzed, such as in a mass spectrometer, where a gas sample is allowed to "leak" into an evacuated region at a very low, controlled rate. The flow regulating valve controls minute flow of gases by allowing the gas to diffuse between two mating surfaces. The structure of the valve is such as to prevent the corrosive feed gas from contacting the bellows which is employed in the operation of the valve, thus preventing deterioration of the bellows.

Shields, W.R.

1960-10-18T23:59:59.000Z

59

Neutron range spectrometer  

DOE Patents (OSTI)

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

Manglos, S.H.

1988-03-10T23:59:59.000Z

60

Magnetic Resonance Facility (Fact Sheet)  

DOE Green Energy (OSTI)

This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

Not Available

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

I I Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

62

Method for calibrating mass spectrometers  

DOE Patents (OSTI)

A method whereby a mass spectra generated by a mass spectrometer is calibrated by shifting the parameters used by the spectrometer to assign masses to the spectra in a manner which reconciles the signal of ions within the spectra having equal mass but differing charge states, or by reconciling ions having known differences in mass to relative values consistent with those known differences. In this manner, the mass spectrometer is calibrated without the need for standards while allowing the generation of a highly accurate mass spectra by the instrument.

Anderson, Gordon A [Benton City, WA; Brands, Michael D [Richland, WA; Bruce, James E [Schwenksville, PA; Pasa-Tolic, Ljiljana [Richland, WA; Smith, Richard D [Richland, WA

2002-12-24T23:59:59.000Z

63

Electron source for a mini ion trap mass spectrometer  

DOE Patents (OSTI)

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Dietrich, D.D.; Keville, R.F.

1995-12-19T23:59:59.000Z

64

Measurement of the Alpha Asymmetry Parameter for the Omega- to Lambda K- Decay  

E-Print Network (OSTI)

We have measured the alpha parameter of the Omega- to Lambda K- decay using data collected with the HyperCP spectrometer during the 1997 fixed-target run at Fermilab. Analyzing a sample of 0.96 million Omega- to Lambda K^-, Lambda to p pi- decays, we obtain alpha_Omega*alpha_Lambda = [1.33+/-0.33(stat)+/-0.52(syst)] x 10^{-2}. With the accepted value of alpha_Lambda, alpha_Omega is found to be [2.07+/-0.51(stat)+/-0.81(syst)] x 10^{-2}.

HyperCP Collaboration; Y. C. Chen; R. A. Burnstein; A. Chakravorty; A. Chan; W. S. Choong; K. Clark; E. C. Dukes; C. Durandet; J. Felix; G. Gidal; P. Gu; H. R. Gustafson; C. Ho; T. Holmstrom; M. Huang; C. James; C. M. Jenkins; D. M. Kaplan; L. M. Lederman; N. Leros; M. J. Longo; F. Lopez; L. C. Lu; W. Luebke; K. B. Luk; K. S. Nelson; H. K. Park; J. P. Perroud; D. Rajaram; H. A. Rubin; P. K. Teng; J. Volk; C. G. White; S. L. White; P. Zyla

2005-02-25T23:59:59.000Z

65

Integration and commissioning of the ATLAS Muon spectrometer  

E-Print Network (OSTI)

The ATLAS experiment at the Large Hadron Collider (LHC) at CERN is currently waiting to record the first collision data in spring 2009. Its muon spectrometer is designed to achieve a momentum resolution of 10% pT(mu) = 1 TeV/c. The spectrometer consists of a system of three superconducting air-core toroid magnets and is instrumented with three layers of Monitored Drift Tube chambers (Cathode Strip Chambers in the extreme forward region) as precision detectors. Resistive Plate Chambers in the barrel and Thin Gap Chambers in the endcap regions provide a fast trigger system. The spectrometer passed important milestones in the last year. The most notable milestone was the installation of the inner layer of endcap muon chambers, which constituted the last big piece of the ATLAS detector to be lowered in the ATLAS cavern. In addition, during the last two years most of the muon detectors were commissioned with cosmic rays while being assembled in the underground experimental cavern. We will report on our experience with the precision and trigger chambers, the optical spectrometer alignment system, the level-1 trigger, and the ATLAS data acquisition system. Results of the global performance of the muon system from data with magnetic field will also be presented.

Alberto Belloni; for the ATLAS collaboration

2008-10-16T23:59:59.000Z

66

CTAX: the US/Japan Cold Neutron Triple-Axis Spectromete at HFIR | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

CTAX-US/Japan Cold Neutron Triple-Axis Spectrometer CTAX-US/Japan Cold Neutron Triple-Axis Spectrometer CTAX US/Japan Cold Neutron Triple-Axis Spectrometer (CG-4C). (larger image) The U.S.-Japan Cold Neutron Triple-Axis Spectrometer (CTAX) is a conventional triple-axis spectrometer with variable incident energy and variable monochromator-sample and sample-analyzer distances. The cold guide 4 bender and guide hall shielding reduce background levels at CG-4C, and the 15-cm-tall guide profile is well exploited by CG-4C's vertically focusing monochromator (PG 002). To enhance accommodation of strong magnetic fields at the sample position and to simplify future polarization analysis, the amount of ferromagnetic material has been minimized in the construction of this instrument. CG-4C is a collaboration of Oak Ridge National Laboratory, the Neutron

67

First Attempts at Antihydrogen Trapping in ALPHA  

SciTech Connect

The ALPHA apparatus is designed to produce and trap antihydrogen atoms. The device comprises a multifunction Penning trap and a superconducting, neutral atom trap having a minimum-B configuration. The atom trap features an octupole magnet for transverse confinement and solenoidal mirror coils for longitudinal confinement. The magnetic trap employs a fast shutdown system to maximize the probability of detecting the annihilation of released antihydrogen. In this article we describe the first attempts to observe antihydrogen trapping.

Andresen, G. B.; Bowe, P. D.; Hangst, J. S. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Bertsche, W.; Butler, E.; Charlton, M.; Humphries, A. J.; Jenkins, M. J.; Joergensen, L. V.; Madsen, N.; Werf, D. P. van der [Department of Physics, Swansea University, Swansea SA2 8PP (United Kingdom); Bray, C. C.; Chapman, S.; Fajans, J.; Povilus, A.; Wurtele, J. S. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Cesar, C. L.; Lambo, R.; Silveira, D. M. [Instituto de Fisica Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972 (Brazil); Fujiwara, M. C. [TRIUMF, 4004 Wesbrook Mall, Vancouver BC, V6T 2A3 (Canada)] (and others)

2008-08-08T23:59:59.000Z

68

Time of flight mass spectrometer  

DOE Patents (OSTI)

A time-of-flight mass spectrometer is described in which ions are desorbed from a sample by nuclear fission fragments, such that desorption occurs at the surface of the sample impinged upon by the fission fragments. This configuration allows for the sample to be of any thickness, and eliminates the need for complicated sample preparation.

Ulbricht, Jr., William H. (Arvada, CO)

1984-01-01T23:59:59.000Z

69

Electron Positron Proton Spectrometer for use at Laboratory for Laser Energetics  

Science Conference Proceedings (OSTI)

The Electron Positron Proton Spectrometer (EPPS) is mounted in a TIM (Ten-Inch Manipulator) system on the Omega-60 or Omega-EP laser facilities at the University of Rochester, Laboratory for Laser Energetics (LLE), when in use, see Fig. 1. The Spectrometer assembly, shown in Fig. 2, is constructed of a steel box containing magnets, surrounded by Lead 6% Antimony shielding with SS threaded insert, sitting on an Aluminum 6061-T6 plate.

Ayers, S L

2010-04-07T23:59:59.000Z

70

An omegatron mass spectrometer for plasma ion species analysis  

DOE Green Energy (OSTI)

An omegatron mass spectrometer which can be used to measure the ion species and charge state distribution in a magnetized plasma is described. In the conventional omegatron, ions are formed as the result of gas ionization by a fine electron beam passing through the center of the analyzer along the magnetic field. In the plasma omegatron, the plasma ions are entering the analyzer through a small floating aperture. We employ a biasing technique to reduce the ion velocity along the magnetic field and, thus, achieve improved ion collection and sensitivity. Experiments have been performed to demonstrate the instrument's operation in the PISCES-A linear plasma device, at a magnetic field {ital B}=1.3 kG. Mass spectra have been obtained in hydrogen, helium, and nitrogen plasmas, and typical results are presented.

Wang, E.Y.; Schmitz, L.; Ra, Y.; LaBombard, B.; Conn, R.W. (Institute of Plasma and Fusion Research, (USA) Department of Mechanical, Aerospace, and Nuclear Engineering, Los Angeles, CA (USA) University of California, Los Angeles, Los Angeles, CA (USA))

1990-08-01T23:59:59.000Z

71

Spin Spectrometer at the ALS and APS  

E-Print Network (OSTI)

5 Spin Spectrometer at the ALS and APS-NIM/SRI07 Figure 3 Ancollected on Beamline 7 at the ALS is shown here. The photonSpin Spectrometer at the ALS and APS-NIM/SRI07 Spin

Tobin, James G; Lawrence Livermore National Laboratory; University of Missouri-Rolla; Boyd Technologies

2008-01-01T23:59:59.000Z

72

THE NCNR NEUTRON SPIN ECHO SPECTROMETER  

Science Conference Proceedings (OSTI)

... The NSE spectrometer, developed in partnership with Exxon Research and Engineering and the Forschungszentrum Jülich in Germany [3], is ...

2000-02-29T23:59:59.000Z

73

Advanced Mass Spectrometers for Hydrogen Isotope Analyses  

DOE Green Energy (OSTI)

This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.

Chastagner, P.

2001-08-01T23:59:59.000Z

74

TAX: Backscattering Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

The Triple-Axis Spectrometer at HFIR Triple-Axis Spectrometer (HB-3) Triple-Axis Spectrometer (HB-3). HB-3 is a colossal flux thermal neutron three-axis spectrometer designed for...

75

Commissioning of the HELIOS spectrometer.  

Science Conference Proceedings (OSTI)

This paper describes the implementation and commissioning of a device based on a new concept for measurements of nuclear reactions in inverse kinematics. The HELIcal Orbit Spectrometer, HELIOS, was commissioned at Argonne National Laboratory by studying the {sup 28}Si(d,p){sup 29}Si reaction in inverse kinematics. This experiment served as a proof of principle for this previously untested concept, and was used to verify the response and performance characteristics of HELIOS.

Lighthall, J. C.; Back, B. B.; Baker, S. I.; Freeman, S. J.; Lee, H. Y.; Kay, B. P.; Marley, S. T.; Rehm, K. E.; Rohrer, J. E.; Schiffer, J. P.; Shetty, D. V.; Vann, A. W.; Winkelbauer, J. R.; Wuosmaa, A. H.; Physics; Western Michigan Univ.; Univ. of Manchester

2010-01-01T23:59:59.000Z

76

Compact mass spectrometer for plasma discharge ion analysis  

DOE Patents (OSTI)

A mass spectrometer and methods are disclosed for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector. 7 figs.

Tuszewski, M.G.

1997-07-22T23:59:59.000Z

77

Compact mass spectrometer for plasma discharge ion analysis  

DOE Patents (OSTI)

A mass spectrometer and methods for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector.

Tuszewski, Michel G. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

78

Portable neutron spectrometer and dosimeter  

DOE Patents (OSTI)

The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

Waechter, David A. (Los Alamos, NM); Erkkila, Bruce H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

79

Developing small vacuum spark as an x-ray source for calibration of an x-ray focusing crystal spectrometer  

SciTech Connect

A new technique of x-ray focusing crystal spectrometers' calibration is the desired result. For this purpose the spectrometer is designed to register radiated copper K{alpha} and K{beta} lines by using a flat {alpha}-quartz crystal. This experiment uses pre-breakdown x-ray emissions in low vacuum of about 2.5-3 mbar. At this pressure the pinch will not form so the plasma will not radiate. The anode material is copper and the capacity of the capacitor bank is 22.6 nF. This experiment designed and mounted a repetitive triggering system to save the operator time making hundreds of shots. This emission amount is good for calibration and geometrical adjustment of an optical crystal x-ray focusing spectrometer.

Ghomeishi, Mostafa; Adikan, Faisal Rafiq Mahamd [Photonic Research Group, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Karami, Mohammad [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2012-10-15T23:59:59.000Z

80

Imaging alpha particle detector  

DOE Patents (OSTI)

A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

Anderson, David F. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

The High-Acceptance Dielectron Spectrometer HADES  

E-Print Network (OSTI)

HADES is a versatile magnetic spectrometer aimed at studying dielectron production in pion, proton and heavy-ion induced collisions. Its main features include a ring imaging gas Cherenkov detector for electron-hadron discrimination, a tracking system consisting of a set of 6 superconducting coils producing a toroidal field and drift chambers and a multiplicity and electron trigger array for additional electron-hadron discrimination and event characterization. A two-stage trigger system enhances events containing electrons. The physics program is focused on the investigation of hadron properties in nuclei and in the hot and dense hadronic matter. The detector system is characterized by an 85% azimuthal coverage over a polar angle interval from 18 to 85 degree, a single electron efficiency of 50% and a vector meson mass resolution of 2.5%. Identification of pions, kaons and protons is achieved combining time-of-flight and energy loss measurements over a large momentum range. This paper describes the main features and the performance of the detector system.

The HADES Collaboration; G. Agakishiev; A. Balanda; B. Bannier; R. Bassini; D. Belver; A. V. Belyaev; A. Blanco; M. Boehmer; J. L. Boyard; P. Braun-Munzinger; P. Cabanelas; E. Castro; S. Chernenko; T. Christ; M. Destefanis; J. Diaz; F. Dohrmann; A. Dybczak; T. Eberl; W. Enghardt; L. Fabbietti; O. V. Fateev; P. Finocchiaro; P. Fonte; J. Friese; I. Froehlich; T. Galatyuk; J. A. Garzon; R. Gernhaeuser; A. Gil; C. Gilardi; M. Golubeva; D. Gonzalez-Diaz; F. Guber; M. Heilmann; T. Heinz; T. Hennino; R. Holzmann; A. Ierusalimov; I. Iori; A. Ivashkin; M. Jurkovic; B. Kaempfer; K. Kanaki; T. Karavicheva; D. Kirschner; I. Koenig; W. Koenig; B. W. Kolb; R. Kotte; F. Krizek; R. Kruecken; W. Kuehn; A. Kugler; A. Kurepin; S. Lang; J. S. Lange; K. Lapidus; T. Liu; L. Lopes; M. Lorenz; L. Maier; A. Mangiarotti; J. Markert; V. Metag; B. Michalska; J. Michel; D. Mishra; E. Moriniere; J. Mousa; C. Muentz; L. Naumann; J. Otwinowski; Y. C. Pachmayer; M. Palka; Y. Parpottas; V. Pechenov; O. Pechenova; T. PerezCavalcanti; J. Pietraszko; W. Przygoda; B. Ramstein; A. Reshetin; M. Roy-Stephan; A. Rustamov; A. Sadovsky; B. Sailer; P. Salabura; A. Schmah; E. Schwab; Yu. G. Sobolev; S. Spataro; B. Spruck; H. Stroebele; J. Stroth; C. Sturm; M. Sudol; A. Tarantola; K. Teilab; P. Tlusty; M. Traxler; R. Trebac; H. Tsertos; V. Wagner; M. Weber; M. Wisniowski; T. Wojcik; J. Wuestenfel; S. Yurevich; Y. V. Zanevsky; P. Zhou; P. Zumbruch

2009-02-19T23:59:59.000Z

82

Compact reflective imaging spectrometer utilizing immersed gratings  

DOE Patents (OSTI)

A compact imaging spectrometer comprising an entrance slit for directing light, a first mirror that receives said light and reflects said light, an immersive diffraction grating that diffracts said light, a second mirror that focuses said light, and a detector array that receives said focused light. The compact imaging spectrometer can be utilized for remote sensing imaging spectrometers where size and weight are of primary importance.

Chrisp, Michael P. (Danville, CA)

2006-05-09T23:59:59.000Z

83

Nuclear diagnostic for fast alpha particles  

DOE Patents (OSTI)

Measurement of the velocity distribution of confined energetic alpha particles resulting from deuterium-tritium fusion reactions in a magnetically contained plasma is provided. The fusion plasma is seeded with energetic boron neutrals for producing, by means of the reaction .sup.10 B (.alpha.,n) .sup.13 N reaction, radioactive nitrogen nuclei which are then collected by a probe. The radioactivity of the probe is then measured by conventional techniques in determining the energy distribution of the alpha particles in the plasma. In a preferred embodiment, diborane gas (B.sub.2 H.sub.6) is the source of the boron neutrals to produce .sup.13 N which decays almost exclusively by positron emission with a convenient half-life of 10 minutes.

Grisham, Larry R. (Lawrence Township, Mercer County, NJ); Post, Jr., Douglass E. (Belle Mead, NJ); Dawson, John M. (Pacific Palisades, CA)

1986-01-01T23:59:59.000Z

84

Miniaturized Mass Spectrometer - Energy Innovation Portal  

Technology Marketing Summary Sandia's invention relates to a miniaturized mass spectrometer using a silicon chip field emitter array as the source of ...

85

ATLAS Muon Spectrometer | Brookhaven and the LHC  

NLE Websites -- All DOE Office Websites (Extended Search)

ATLAS Muon Spectrometer small wheels Brookhaven National Laboratory led the development of the 32 muon detectors in the inner ring of the ATLAS detector's "small wheels." (A small...

86

Pulsed Ionization Source for Ion Mobility Spectrometers  

Mobility Spectrometers Potential Advantages ... ORNL’s new wave of detection devices based on ion mobility spectrometry offer enhanced sensitivity and

87

Calibrating the DARHT Electron Spectrometer with Negative Ions  

DOE Green Energy (OSTI)

Negative ions of hydrogen and oxygen have been used to calibrate the DARHT electron spectrometer over the momentum range of 2 to 20 MeV/c. The calibration was performed on September 1, 3, and 8, 2004, and it is good to 0.5% absolute, provided that instrument alignment is carefully controlled. The momentum in MeV/c as a function of magnetic field (B in Gauss) and position in the detector plane (X in mm) is: P = (B-6.28)/(108.404-0.1935*X)

R. Trainham (STL), A. P. Tipton (LAO), and R. R. Bartech (LANL)

2005-11-01T23:59:59.000Z

88

A Compact Lightweight Aerosol Spectrometer Probe (CLASP)  

Science Conference Proceedings (OSTI)

The Compact Lightweight Aerosol Spectrometer Probe (CLASP) is an optical particle spectrometer capable of measuring size-resolved particle concentrations in 16 user-defined size bins spanning diameters in the range 0.24 < D < 18.5 ?m at a rate of ...

Martin K. Hill; Barbara J. Brooks; Sarah J. Norris; Michael H. Smith; Ian M. Brooks; Gerrit de Leeuw

2008-11-01T23:59:59.000Z

89

Compact time-of-flight mass spectrometer  

SciTech Connect

This paper describes a time-of-flight mass spectrometer developed for measuring the parameters of a pulsed hydrogen beam. The duration of an electron-beam current pulse in the ionizer of the mass spectrometer can be varied within 2-20 usec, the pulse electron current is 0.6 mA, and the electron energy is 250 eV. The time resolution of the mass spectrometer is determined by the repetition period of the electron-beam current pulses and is 40 usec. The mass spectrometer has 100% transmission in the direction of motion of molecular-beam particles. The dimension of the mass spectrometer is 7 cm in this direction. The mass resolution is sufficient for determination of the composition of the hydrogen beam.

Belov, A.S.; Kubalov, S.A.; Kuzik, V.F.; Yakushev, V.P.

1986-02-01T23:59:59.000Z

90

E parallel B canted detector neutral-particle spectrometer  

DOE Green Energy (OSTI)

A multichannel, mass-discriminating, neutral-particle spectrometer using parallel E and B analyzer fields has been operational on the Doublet III tokamak. The device records 60 energy channels each of hydrogen and deuterium, simultaneously, during a shot with a dynamic range in energy of greater than 20. Its unique feature is a microchannel plate detector plane set at an angle to the exit face of the magnet. This angled detector plane linearizes the columns of each mass which simplifies the detector design, and permits the magnet gap to be very small. The narrow gap minimizes figure field effects on particle trajectories and simplifies power supply and cooling design. Details are given on the design, calibration, and instrumentation of the device, as well as on its operation and experimental results.

Armentrout, C.J.; Bramson, G.; Evanko, R.

1985-11-01T23:59:59.000Z

91

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Time-of-flight mass spectrometer comprising a first drift...

92

NON-THERMAL RESPONSE OF THE CORONA TO THE MAGNETIC FLUX DISPERSAL IN THE PHOTOSPHERE OF A DECAYING ACTIVE REGION  

Science Conference Proceedings (OSTI)

We analyzed Solar Dynamics Observatory line-of-sight magnetograms for a decaying NOAA active region (AR) 11451 along with co-temporal Extreme-Ultraviolet Imaging Spectrometer (EIS) data from the Hinode spacecraft. The photosphere was studied via time variations of the turbulent magnetic diffusivity coefficient, {eta}(t), and the magnetic power spectrum index, {alpha}, through analysis of magnetogram data from the Helioseismic and Magnetic Imager (HMI). These measure the intensity of the random motions of magnetic elements and the state of turbulence of the magnetic field, respectively. The time changes of the non-thermal energy release in the corona was explored via histogram analysis of the non-thermal velocity, v {sub nt}, in order to highlight the largest values at each time, which may indicate an increase in energy release in the corona. We used the 10% upper range of the histogram of v {sub nt} (which we called V {sup upp} {sub nt}) of the coronal spectral line of Fe XII 195 A. A 2 day time interval was analyzed from HMI data, along with the EIS data for the same field of view. Our main findings are the following. (1) The magnetic turbulent diffusion coefficient, {eta}(t), precedes the upper range of the v {sub nt} with the time lag of approximately 2 hr and the cross-correlation coefficient of 0.76. (2) The power-law index, {alpha}, of the magnetic power spectrum precedes V {sup upp} {sub nt} with a time lag of approximately 3 hr and the cross-correlation coefficient of 0.5. The data show that the magnetic flux dispersal in the photosphere is relevant to non-thermal energy release dynamics in the above corona. The results are consistent with the nanoflare mechanism of the coronal heating, due to the time lags being consistent with the process of heating and cooling the loops heated by nanoflares.

Harra, L. K. [UCL-Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Abramenko, V. I. [Big Bear Solar Observatory, 40386 N. Shore Lane, Big Bear City, CA 92314 (United States)

2012-11-10T23:59:59.000Z

93

The Vibrational Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Vibrational Spectrometer at SNS VISION VISION is best thought of as the neutron analogue of an infrared-Raman spectrometer. It is optimized to characterize molecular vibrations in...

94

HYSPEC: the Hybrid Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Spectrometer at SNS Hybrid Spectrometer Schematic of the HYSPEC instrument Developed by a team from leading U.S. universities and national laboratories and an international...

95

Gas sampling system for a mass spectrometer  

DOE Patents (OSTI)

The present invention relates generally to a gas sampling system, and specifically to a gas sampling system for transporting a hazardous process gas to a remotely located mass spectrometer. The gas sampling system includes a capillary tube having a predetermined capillary length and capillary diameter in communication with the supply of process gas and the mass spectrometer, a flexible tube surrounding and coaxial with the capillary tube intermediate the supply of process gas and the mass spectrometer, a heat transfer tube surrounding and coaxial with the capillary tube, and a heating device in communication the heat transfer tube for substantially preventing condensation of the process gas within the capillary tube.

Taylor, Charles E; Ladner, Edward P

2003-12-30T23:59:59.000Z

96

High-resolution crystal spectrometer for the 10-60 (angstrom) EUV region  

DOE Green Energy (OSTI)

A vacuum crystal spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines with wavelength in the extreme ultraviolet region up to 60 Angstroms. The instrument utilizes a flat octadecyl hydrogen maleate (OHM) crystal and a thin-window 1-D position-sensitive gas proportional detector. This detector employs a 1 {micro}m-thick 100 x8 mm{sup 2} aluminized polyimide window and operates at one atmosphere pressure. The spectrometer has been implemented on the Livermore electron beam ion traps. The performance of the instrument is illustrated in measurements of the newly discovered magnetic field-sensitive line in Ar{sup 8+}.

Beiersdorfer, P; Brown, G V; Goddard, R; Wargelin, B J

2004-02-20T23:59:59.000Z

97

Development of an Inexpensive Raindrop Size Spectrometer  

Science Conference Proceedings (OSTI)

The deployment of weather radar, notably in mountainous terrain with many microclimates, requires the use of several or even many drop size spectrometers to provide confidence in the quantitative relation between radar reflectivity and rainfall. ...

William Henson; Geoff Austin; Harry Oudenhoven

2004-11-01T23:59:59.000Z

98

LCLS Injector Straight-Ahead Spectrometer  

Science Conference Proceedings (OSTI)

The spectrometer design was modified to allow the measurement of uncorrelated energy spread for the nominal lattice. One bunch from every 120 each second would be sent to the straight ahead spectrometer while the transverse cavity is on. The implementation of this 'stealing mode' will not be available for the LCLS commissioning and the early stage of operation. However, the spectrometer was redesigned to retain that option. The energy feedback relies independently on the beam position of the beam in the dispersive section of dogleg 1 (DL1). The main modification of the spectrometer design is the Pole face rotation of 7.5 degrees on both entrance and exit faces. The location and range of operation of the 3 quadrupoles remains unchanged relative to those of the earlier design.

Limborg-Deprey , C.

2010-12-10T23:59:59.000Z

99

Multidetector calibration for mass spectrometers  

SciTech Connect

The International Atomic Energy Agency`s Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (1) peak-shift experiments and (2) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements were made by shifting the isotopes to various Faraday detectors. Two different peak-shifting schemes were used to measure plutonium (UK Pu5/92138) samples. For peak-jump experiments, ion intensities were measured in a reference Faraday detector for a single isotope and compared with those measured in the other Faraday detectors. Repeated measurements were made by switching back-and-forth between the reference Faraday detector and a selected Faraday detector. This switching procedure is repeated for all Faraday detectors. Peak-jump experiments were performed with replicate measurements of {sup 239}Pu, {sup 187}Re, and {sup 238}U. Detector efficiency factors were estimated for both peak-jump and peak-shift experiments using a flexible calibration model to statistically analyze both types of multidetector calibration experiments. Calculated detector efficiency factors were shown to depend on both the material analyzed and the experimental conditions. A single detector efficiency factor is not recommended for each detector that would be used to correct routine sample analyses. An alternative three-run peak-shift sample analysis should be considered. A statistical analysis of the data from this peak-shift experiment can adjust the isotopic ratio estimates for detector differences due to each sample analysis.

Bayne, C.K. [Oak Ridge National Lab., TN (United States); Donohue, D.L.; Fiedler, R. [IAEA, Seibersdorf (Austria). Safeguards Analytical Lab.

1994-06-01T23:59:59.000Z

100

1987 calibration of the TFTR neutron spectrometers  

SciTech Connect

The {sup 3}He neutron spectrometer used for measuring ion temperatures and the NE213 proton recoil spectrometer used for triton burnup measurements were absolutely calibrated with DT and DD neutron generators placed inside the TFTR vacuum vessel. The details of the detector response and calibration are presented. Comparisons are made to the neutron source strengths measured from other calibrated systems. 23 refs., 19 figs., 6 tabs.

Barnes, C.W.; Strachan, J.D. (Los Alamos National Lab., NM (USA); Princeton Univ., NJ (USA). Plasma Physics Lab.)

1989-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

BRAHMS (Broad Range Hadron Magnetic Spectrometer) Figures and Data Archive  

DOE Data Explorer (OSTI)

See also the complete list of publications, multimedia presentations, and related papers at http://www4.rcf.bnl.gov/brahms/WWW/publications.html

None

102

NSE: the Neutron Spin Echo Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Spin Echo Spectrometer at SNS Spin Echo Spectrometer at SNS NSE NSE is funded and operated by the Jülich Centre for Neutron Science. The SNS NSE instrument provides ultrahigh resolution spectroscopy with a Fourier time range that covers τ = 1 ps to a nominal 350 ns with a high effective neutron flux, aiming to be the best of its class in both resolution and dynamic range (please refer to the instrument fact sheet for a detailed current status). Researchers use this instrument to investigate soft condensed matter and complex fluids applications in a variety of fields. The planned optional ferromagnetic and intensity-modulated modes will allow for detailed investigation of magnetic samples and phenomena. The design of the NSE spectrometer takes full advantage of recent progress in neutron optics and polarizing supermirror microbenders,1,2 resulting in

103

CNCS: the Cold Neutron Chopper Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Cold Neutron Chopper Spectrometer at SNS Cold Neutron Chopper Spectrometer at SNS CNCS detector array Interior of the CNCS detector array. CNCS is a high-resolution, direct-geometry, multi-chopper inelastic spectrometer designed to provide flexibility in the choice of energy resolution and to perform best at low incident energies (2 to 50 meV). Although the detector coverage around the sample is 1.7 sr, a later upgrade to 3 sr is possible. Experiments at CNCS typically use energy resolutions between 10 and 500 µeV. A broad variety of scientific problems, ranging from complex and quantum fluids to magnetism and chemical spectroscopy, are being addressed through experiments at CNCS. Applications Schematic of CNCS (larger image). Complex fluids: dilute protein solutions, biological gels, selective

104

Long range alpha particle detector  

DOE Patents (OSTI)

An alpha particle detector capable of detecting alpha radiation from distant sources. A high voltage is generated near a conductive mesh while a fan draws air containing air molecules ionized by alpha particles across the mesh. The current in the mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

Wolf, M.A.; McAdtee, J.L. III; Unruh, W.P.; Cucchiadra, A.L.; Huchton, R.L.

1990-03-13T23:59:59.000Z

105

Simulation of Alpha Particles in Rotating Plasma Interacting with a Stationary Ripple  

SciTech Connect

Superthermal ExB rotation can provide magnetohydrodynamic (MHD) stability and enhanced confinement to axisymmetric mirrors. However, the rotation speed has been limited by phenomena at end electrodes. A new prediction is that rotation might instead be produced using a magnetic ripple and alpha particle kinetic energy, in an extension of the alpha channeling concept. The interaction of alpha particles with the ripple results in visually interesting and practically useful orbits.

Abraham J. Fetterman and Nathaniel J. Fisch

2011-01-11T23:59:59.000Z

106

Five-element Johann-type x-ray emission spectrometer with a single-photon-counting pixel detector  

Science Conference Proceedings (OSTI)

A Johann-type spectrometer with five spherically bent crystals and a pixel detector was constructed for a range of hard x-ray photon-in photon-out synchrotron techniques, covering a Bragg-angle range of 60 deg. - 88 deg. The spectrometer provides a sub emission line width energy resolution from sub-eV to a few eV and precise energy calibration, better than 1.5 eV for the full range of Bragg angles. The use of a pixel detector allows fast and easy optimization of the signal-to-background ratio. A concentration detection limit below 0.4 wt% was reached at the Cu K{alpha}{sub 1} line. The spectrometer is designed as a modular mobile device for easy integration in a multi-purpose hard x-ray synchrotron beamline, such as the SuperXAS beamline at the Swiss Light Source.

Kleymenov, Evgeny; Bokhoven, Jeroen A. van [Paul Scherrer Institut, 5232 Villigen (Switzerland); ETH Zurich, Institute for Chemical and Bioengineering, 8093 Zurich (Switzerland); David, Christian; Janousch, Markus; Studer, Marco; Willimann, Markus; Bergamaschi, Anna; Henrich, Beat; Nachtegaal, Maarten [Paul Scherrer Institut, 5232 Villigen (Switzerland); Glatzel, Pieter [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Alonso-Mori, Roberto [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States)

2011-06-15T23:59:59.000Z

107

Seven Channel Multi-collector Isotope Ratio Mass Spectrometer  

Science Conference Proceedings (OSTI)

A new magnetic sector mass spectrometer that utilizes seven full-sized discrete dynode electron multipliers operating simultaneously has been designed, constructed and is in preliminary testing. The instrument utilizes a newly developed ion dispersion lens that enables the mass dispersed individual isotope beams to be separated sufficiently (35 mm) to allow a full-sized discrete dynode pulse counting multiplier to be used for each beam. The ion dispersion lens is a two element electrostatic 90 degree sector device that causes the beam-to-beam dispersion to increase faster than the intra-beam dispersion. Each multiplier is contained in an isolated case with a deflector/condenser lens at the entrance. A 9-sample filament cartridge is mounted on a micro-manipulator two-axis stage that enables adjustment of the filament position with 10 micron resolution within the ion lens. Results of initial testing with actinides will be presented.

Anthony D. Appelhans

2008-07-01T23:59:59.000Z

108

Partial pressure measurements with an active spectrometer  

SciTech Connect

Partial pressure neutral ga measurements have been made using a commercial Penning gauge in conjunction with an active spectrometer. In prior work utilizing bandpass filters and conventional spectrometers, trace concentrations of the hydrogen isotopes H, D, T and of the noble gases He, Ne and Ar were determined from characteristic spectral lines in the light emitted by the neutral species of these elements. For all the elements mentioned, the sensitivity was limited by spectral contamination from a pervasive background of molecular hydrogen radiation. The active spectrometer overcomes this limitations by means of a digital lock-in method and correlation with reference spectra. Preliminary measurements of an admixture containing a trace amount of neon in deuterium show better than a factor of 20 improvement in sensitivity over conventional techniques. This can be further improved by correlating the relative intensities of multiple lines to sets of reference spectra.

Brooks, N.H.; Jensen, T.H. [General Atomics, San Diego, CA (United States); Colchin, R.J.; Maingi, R.; Wade, M.R. [Oak Ridge National Lab., TN (United States); Finkenthal, D.F. [Palomar Coll. (United States); Naumenko, N. [Inst. for Atomic and Molecular Physics (Japan); Tugarinov, S. [TRINITI (United States)

1998-07-01T23:59:59.000Z

109

A compact multichannel spectrometer for Thomson scattering  

Science Conference Proceedings (OSTI)

The availability of high-efficiency volume phase holographic (VPH) gratings and intensified CCD (ICCD) cameras have motivated a simplified, compact spectrometer for Thomson scattering detection. Measurements of T{sub e} 100 eV by a 2072 l/mm VPH grating. The spectrometer uses a fast-gated ({approx}2 ns) ICCD camera for detection. A Gen III image intensifier provides {approx}45% quantum efficiency in the visible region. The total read noise of the image is reduced by on-chip binning of the CCD to match the 8 spatial channels and the 10 spectral bins on the camera. Three spectrometers provide a minimum of 12 spatial channels and 12 channels for background subtraction.

Schoenbeck, N. L.; Schlossberg, D. J.; Dowd, A. S.; Fonck, R. J.; Winz, G. R. [Department of Engineering Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2012-10-15T23:59:59.000Z

110

Compact hydrogen/helium isotope mass spectrometer  

DOE Patents (OSTI)

The compact hydrogen and helium isotope mass spectrometer of the present invention combines low mass-resolution ion mass spectrometry and beam-foil interaction technology to unambiguously detect and quantify deuterium (D), tritium (T), hydrogen molecule (H.sub.2, HD, D.sub.2, HT, DT, and T.sub.2), .sup.3 He, and .sup.4 He concentrations and concentration variations. The spectrometer provides real-time, high sensitivity, and high accuracy measurements. Currently, no fieldable D or molecular speciation detectors exist. Furthermore, the present spectrometer has a significant advantage over traditional T detectors: no confusion of the measurements by other beta-emitters, and complete separation of atomic and molecular species of equivalent atomic mass (e.g., HD and .sup.3 He).

Funsten, Herbert O. (Los Alamos, NM); McComas, David J. (Los Alamos, NM); Scime, Earl E. (Morgantown, WV)

1996-01-01T23:59:59.000Z

111

Geochronology of recent sediments from the Cariaco Trench (Venezuela) by Alpha Spectrometry of {sup 210}Pb ({sup 210}Po)  

Science Conference Proceedings (OSTI)

210Pb concentration in marine sediments of the Cariaco Trench (North-East of Venezuela) was measured through the analysis of 210Po alpha emissions, which can be assumed to be in secular equilibrium with 210Pb. The analysed sediment core has a length of 1.9 m. The results allowed to apply the CF:CS dating model (Constant Flux and Constant Supply). The sedimentation rate was estimated to be 0.25 cm/y. As far as we know this is the first {alpha}- dating carried out in the country, performed with an alpha spectrometer recently funded by the IAEA.

Arriojas, A.; Barros, H.; Palacios, D.; Sajo-Bohus, L. [Laboratorio de Fisica Nuclear, Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of); Hurtado, S.; Villa, M. [Centro de Investigacion, Tecnologia e Innovacion de la Universidad de Sevilla (Spain); Perez, K.; Alfonso, J. [Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas (Venezuela, Bolivarian Republic of)

2010-08-04T23:59:59.000Z

112

Long range alpha particle detector  

DOE Patents (OSTI)

An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

MacArthur, Duncan W. (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM); McAtee, James L. (Los Alamos, NM); Unruh, Wesley P. (Los Alamos, NM); Cucchiara, Alfred L. (Los Alamos, NM); Huchton, Roger L. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

113

Long range alpha particle detector  

DOE Patents (OSTI)

An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

MacArthur, D.W.; Wolf, M.A.; McAtee, J.L.; Unruh, W.P.; Cucchiara, A.L.; Huchton, R.L.

1993-02-02T23:59:59.000Z

114

Use of /sup 3/He/sup + +/ ICRF minority heating to simulate alpha particle heating  

DOE Patents (OSTI)

It is an object of the present invention to provide a better understanding of alpha particle behavior in a magnetically confined, energetic plasma. Another object of the present invention is to provide an improved means and method for studying and measuring the energy distribution of heated alpha particles in a confined plasma. Yet another object of the present invention is to permit detailed analysis of energetic alpha particle behavior in a magnetically confined plasma for use in near term fusion reactor experiments. A still further object of the present invention is to simulate energetic alpha particle behavior in a deuterium-tritium plasma confined in a fusion reactor without producing the neutron activation associated with the thus produced alpha particles.

Post, D.E. Jr.; Hwang, D.Q.; Hovey, J.

1983-11-16T23:59:59.000Z

115

Development and performance of a miniature, low cost mass spectrometer  

E-Print Network (OSTI)

A miniature, low cost mass spectrometer has been developed that is capable of unit resolution over a mass range of 10 to 50 AMU. The design of the mass spectrometer incorporates several new features that enhance the ...

Hemond, Brian D. (Brian David Thomson)

2011-01-01T23:59:59.000Z

116

A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER  

E-Print Network (OSTI)

: Pauli exclusion . . . . 61 4.7.3 Fermi gas model . . . . . . . . . . . . . . . . . . . . 62 4.7.4 Termsanecke and Masson . . . . . . . . . . . . 82 V. Solenoid Ion Optics and Magnetic Dispersion . . . . . . . . . 88 5-aperture control of fractional magnetic dispersion with a solenoid

O'Donnell, Tom

117

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... The Primary Spectrometer High energy neutrons and gammas ... steradians and arranged in three banks: The middle bank detector scattering ...

118

Passive Millimeter-Wave Spectrometer for Remote Chemical Detection  

NLE Websites -- All DOE Office Websites (Extended Search)

Passive Millimeter-Wave Spectrometer for Remote Chemical Detection Multimedia Nuclear Systems Analysis Engineering Analysis Nonproliferation and National Security Detection &...

119

A TRANSISTORIZED ALPHA COUNTER FOR AN ALPHA GAUGE  

SciTech Connect

A transistorized instrument prototype was designed and constructed to replace a vacuum-tube instrument in an alpha gauge, which measures the thickness density of gases. The instrument amplifies, shapes, discriminates, and counts alpha pulses from a Au-Si surface-barrier detector exposed to an alpha source in a gas-filled chamber. The circuit consists of a charge-sensitive preamplifier, a main amplifier with pulse clipping, a Schmitt trigger, a diode pump, and a count rate meter. Preliminary tests gave results comparable to the vacuum-tube instrument. Accuracy of counting was within 10% for 0.5- to 10-Mev alpha particles emitted at a maximum rate of 10/sup 6 per sec. The instrument was stable at 25 to 55 deg C, is small and portable, and costs less than 0. An infinitely thick, alpha source that will give a high count rate is being constructed for final tests. (auth)

Kopp, M.C.

1962-08-23T23:59:59.000Z

120

HyperCP: A high-rate spectrometer for the study of charged hyperon and kaon decays  

E-Print Network (OSTI)

The HyperCP experiment (Fermilab E871) was designed to search for rare phenomena in the decays of charged strange particles, in particular CP violation in $\\Xi$ and $\\Lambda$ hyperon decays with a sensitivity of $10^{-4}$. Intense charged secondary beams were produced by 800 GeV/c protons and momentum-selected by a magnetic channel. Decay products were detected in a large-acceptance, high-rate magnetic spectrometer using multiwire proportional chambers, trigger hodoscopes, a hadronic calorimeter, and a muon-detection system. Nearly identical acceptances and efficiencies for hyperons and antihyperons decaying within an evacuated volume were achieved by reversing the polarities of the channel and spectrometer magnets. A high-rate data-acquisition system enabled 231 billion events to be recorded in twelve months of data-taking.

HyperCP collaboration; R. A. Burnstein; A. Chakravorty; A. Chan; Y. C. Chen; W. -S. Choong; K. Clark; E. C. Dukes; C. Durandet; J. Felix; R. Fuzesy; G. Gidal; P. Gu; H. R. Gustafson; C. Ho; T. Holmstrom; M. Huang; C. James; C. M. Jenkins; T. D. Jones; D. M. Kaplan; L. M. Lederman; N. Leros; M. J. Longo; F. Lopez; L. C. Lu; W. Luebke; K. -B. Luk; K. S. Nelson; H. K. Park; J. -P. Perroud; D. Rajaram; H. A. Rubin; P. K. Teng; B. Turko; J. Volk; C. G. White; S. L. White; P. Zyla

2004-05-14T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Compact imaging spectrometer utilizing immersed gratings  

DOE Patents (OSTI)

A compact imaging spectrometer with an immersive diffraction grating that compensates optical distortions. The imaging spectrometer comprises an entrance slit for transmitting light, means for receiving the light and directing the light, an immersion grating, and a detector array. The entrance slit, the means for receiving the light, the immersion grating, and the detector array are positioned wherein the entrance slit transmits light to the means for receiving the light and the means for receiving the light directs the light to the immersion grating and the immersion grating receives the light and directs the light to the means for receiving the light, and the means for receiving the light directs the light to the detector array.

Chrisp, Michael P. (Danville, CA); Lerner, Scott A. (Corvallis, OR); Kuzmenko, Paul J. (Livermore, CA); Bennett, Charles L. (Livermore, CA)

2007-07-03T23:59:59.000Z

122

Quench anaylsis of MICE spectrometer superconducting solenoid  

SciTech Connect

MICE superconducting spectrometer solenoids fabrication and tests are in progress now. First tests of the Spectrometer Solenoid discovered some issues which could be related to the chosen passive quench protection system. Both solenoids do not have heaters and quench propagation relied on the 'quench back' effect, cold diodes, and shunt resistors. The solenoids have very large inductances and stored energy which is 100% dissipated in the cold mass during a quench. This makes their protection a challenging task. The paper presents the quench analysis of these solenoids based on 3D FEA solution of coupled transient electromagnetic and thermal problems. The simulations used the Vector Fields QUENCH code. It is shown that in some quench scenarios, the quench propagation is relatively slow and some areas can be overheated. They describe ways of improving the solenoids quench protection in order to reduce the risk of possible failure.

Kashikhin, Vladimir; Bross, Alan; /Fermilab; Prestemon, Soren; / /LBL, Berkeley

2011-09-01T23:59:59.000Z

123

Portable gas chromatograph-mass spectrometer  

DOE Patents (OSTI)

A gas chromatograph-mass spectrometer (GC-MS) for use as a field portable organic chemical analysis instrument. The GC-MS is designed to be contained in a standard size suitcase, weighs less than 70 pounds, and requires less than 600 watts of electrical power at peak power (all systems on). The GC-MS includes: a conduction heated, forced air cooled small bore capillary gas chromatograph, a small injector assembly, a self-contained ion/sorption pump vacuum system, a hydrogen supply, a dual computer system used to control the hardware and acquire spectrum data, and operational software used to control the pumping system and the gas chromatograph. This instrument incorporates a modified commercial quadrupole mass spectrometer to achieve the instrument sensitivity and mass resolution characteristic of laboratory bench top units.

Andresen, B.D.; Eckels, J.D.; Kimmins, J.F.; Myers, D.W.

1994-12-31T23:59:59.000Z

124

Time Dispersive Spectrometer Using Digital Switching Means  

DOE Patents (OSTI)

Methods and apparatus are described for time dispersive spectroscopy. In particular, a modulated flow of ionized molecules of a sample are introduced into a drift region of an ion spectrometer. The ions are subsequently detected by an ion detector to produce an ion detection signal. The ion detection signal can be modulated to obtain a signal useful in assaying the chemical constituents of the sample.

Tarver, III, Edward E. (Livermore, CA); Siems, William F. (Spokane, WA)

2004-09-07T23:59:59.000Z

125

Expert overseer for mass spectrometer system  

DOE Patents (OSTI)

An expert overseer for the operation and real-time management of a mass spectrometer and associated laboratory equipment. The overseer is a computer-based expert diagnostic system implemented on a computer separate from the dedicated computer used to control the mass spectrometer and produce the analysis results. An interface links the overseer to components of the mass spectrometer, components of the laboratory support system, and the dedicated control computer. Periodically, the overseer polls these devices and as well as itself. These data are fed into an expert portion of the system for real-time evaluation. A knowledge base used for the evaluation includes both heuristic rules and precise operation parameters. The overseer also compares current readings to a long-term database to detect any developing trends using a combination of statistical and heuristic rules to evaluate the results. The overseer has the capability to alert lab personnel whenever questionable readings or trends are observed and provide a background review of the problem and suggest root causes and potential solutions, or appropriate additional tests that could be performed. The overseer can change the sequence or frequency of the polling to respond to an observation in the current data.

Filby, Evan E. (Idaho Falls, ID); Rankin, Richard A. (Ammon, ID)

1991-01-01T23:59:59.000Z

126

Expert overseer for mass spectrometer system  

DOE Patents (OSTI)

An expert overseer for the operation and real-time management of a mass spectrometer and associated laboratory equipment. The overseer is a computer-based expert diagnostic system implemented on a computer separate from the dedicated computer used to control the mass spectrometer and produce the analysis results. An interface links the overseer to components of the mass spectrometer, components of the laboratory support system, and the dedicated control computer. Periodically, the overseer polls these devices and as well as itself. These data are fed into an expert portion of the system for real-time evaluation. A knowledge base used for the evaluation includes both heuristic rules and precise operation parameters. The overseer also compares current readings to a long-term database to detect any developing trends using a combination of statistical and heuristic rules to evaluate the results. The overseer has the capability to alert lab personnel whenever questionable readings or trends are observed and provide a background review of the problem and suggest root causes and potential solutions, or appropriate additional tests that could be performed. The overseer can change the sequence or frequency of the polling to respond to an observation in the current data.

Filby, E.E.; Rankin, R.A.

1989-04-04T23:59:59.000Z

127

Results from a Prototype Chicane-Based Energy Spectrometer for a Linear Collider  

E-Print Network (OSTI)

The International Linear Collider and other proposed high energy e+ e- machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 1e-4. This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006--2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5e-4 was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance.

A. Lyapin; H. J. Schreiber; M. Viti; C. Adolphsen; R. Arnold; S. Boogert; G. Boorman; M. V. Chistiakova; F. Gournaris; V. Duginov; C. Hast; M. D. Hildreth; C. Hlaing; F. Jackson; O. Khainovsky; Yu. G. Kolomensky; S. Kostromin; K. Kumar; B. Maiheu; D. McCormick; D. J. Miller; N. Morozov; T. Orimoto; E. Petigura; M. Sadre-Bazzaz; M. Slater; Z. Szalata; M. Thomson; D. Ward; M. Wendt; M. Wing; M. Woods

2010-11-01T23:59:59.000Z

128

BT9 Triple-axis spectrometer  

Science Conference Proceedings (OSTI)

... translations, make sure that the motors are powered ... active if the rotating collimator motor is off ... SAFETY NOTE: When using high magnetic fields be ...

129

Use of .sup.3 He.sup.30 + ICRF minority heating to simulate alpha particle heating  

DOE Patents (OSTI)

Neutron activation due to high levels of neutron production in a first heated deuterium-tritium plasma is substantially reduced by using Ion Cyclotron Resonance Frequency (ICRF) heating of energetic .sup.3 He.sup.++ ions in a second deuterium-.sup.3 He.sup.++ plasma which exhibit an energy distribution and density similar to that of alpha particles in fusion reactor experiments to simulate fusion alpha particle heating in the first plasma. The majority of the fast .sup.3 He.sup.++ ions and their slowing down spectrum can be studied using either a modulated hydrogen beam source for producing excited states of He.sup.+ in combination with spectrometers or double charge exchange with a high energy neutral lithium beam and charged particle detectors at the plasma edge. The maintenance problems thus associated with neutron activation are substantially reduced permitting energetic alpha particle behavior to be studied in near term large fusion experiments.

Post, Jr., Douglass E. (Belle Mead, NJ); Hwang, David Q. (Lawrencevill, NJ); Hovey, Jane (Plainsboro, NJ)

1986-04-22T23:59:59.000Z

130

Isochronal annealing of radiation damage in (alpha)- and (delta)-Pu alloys  

Science Conference Proceedings (OSTI)

Magnetic isochronal annealing curves were measured on specimens of self damaged {alpha}-Pu and several {delta}-Pu alloys stabilized by Ga and Am. These results are compared to one another and to isochronal resistivity annealing curves, where distinct differences are observed between the magnetic and resistive annealing for the case of {delta}-Pu. The first stage of annealing observed in the resistivity measurements is largely missing from the magnetic measurements, indicating that interstitials contribute little if any signal to the magnetization, while the onset of vacancy migration is strongly reflected in the magnetization signal.

McCall, S K; Fluss, M J; Chung, B W; Haire, R G

2009-06-22T23:59:59.000Z

131

Compact proton spectrometers for measurements of shock  

Science Conference Proceedings (OSTI)

The compact Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the National Ignition Facility (NIF) as a National Ignition Campaign (NIC) diagnostic. The WRF measures the spectrum of protons from D-{sup 3}He reactions in tuning-campaign implosions containing D and {sup 3}He gas; in this work we report on the first proton spectroscopy measurement on the NIF using WRFs. The energy downshift of the 14.7-MeV proton is directly related to the total {rho}R through the plasma stopping power. Additionally, the shock proton yield is measured, which is a metric of the final merged shock strength.

Mackinnon, A; Zylstra, A; Frenje, J A; Seguin, F H; Rosenberg, M J; Rinderknecht, H G; Johnson, M G; Casey, D T; Sinenian, N; Manuel, M; Waugh, C J; Sio, H W; Li, C K; Petrasso, R D; Friedrich, S; Knittel, K; Bionta, R; McKernan, M; Callahan, D; Collins, G; Dewald, E; Doeppner, T; Edwards, M J; Glenzer, S H; Hicks, D; Landen, O L; London, R; Meezan, N B

2012-05-02T23:59:59.000Z

132

Ion mobility spectrometer with virtual aperture grid  

DOE Patents (OSTI)

An ion mobility spectrometer does not require a physical aperture grid to prevent premature ion detector response. The last electrodes adjacent to the ion collector (typically the last four or five) have an electrode pitch that is less than the width of the ion swarm and each of the adjacent electrodes is connected to a source of free charge, thereby providing a virtual aperture grid at the end of the drift region that shields the ion collector from the mirror current of the approaching ion swarm. The virtual aperture grid is less complex in assembly and function and is less sensitive to vibrations than the physical aperture grid.

Pfeifer, Kent B. (Los Lunas, NM); Rumpf, Arthur N. (Albuquerque, NM)

2010-11-23T23:59:59.000Z

133

Lead Slowing Down Spectrometer Status Report  

Science Conference Proceedings (OSTI)

This report documents the progress that has been completed in the first half of FY2012 in the MPACT-funded Lead Slowing Down Spectrometer project. Significant progress has been made on the algorithm development. We have an improve understanding of the experimental responses in LSDS for fuel-related material. The calibration of the ultra-depleted uranium foils was completed, but the results are inconsistent from measurement to measurement. Future work includes developing a conceptual model of an LSDS system to assay plutonium in used fuel, improving agreement between simulations and measurement, design of a thorium fission chamber, and evaluation of additional detector techniques.

Warren, Glen A.; Anderson, Kevin K.; Bonebrake, Eric; Casella, Andrew M.; Danon, Yaron; Devlin, M.; Gavron, Victor A.; Haight, R. C.; Imel, G. R.; Kulisek, Jonathan A.; O'Donnell, J. M.; Weltz, Adam

2012-06-07T23:59:59.000Z

134

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber. Available for thumbnail of Feynman Center (505) 665-9090 Email Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber; a means of introducing an analyte of interest into the first drift region; a pulsed ionization source which produces molecular ions from said analyte of interest; a first foil positioned between the first drift region and the second drift region, which dissociates said molecular ions into constituent

135

Electro-optic Phase Grating Streak Spectrometer  

SciTech Connect

The electro-optic phase grating streak spectrometer (EOPGSS) generates a time-resolved spectra equivalent to that obtained with a conventional spectrometer/streak camera combination, but without using a streak camera (by far the more expensive and problematic component of the conventional system). The EOPGSS is based on a phase, rather than an amplitude grating. Further, this grating is fabricated of electro-optic material such as, for example, KD*P, by either etching grooves into an E-O slab, or by depositing lines of the E-O material onto an optical flat. An electric field normal to the grating alters the material’s index of refraction and thus affects a shift (in angle) of the output spectrum. Ramping the voltage streaks the spectrum correspondingly. The streak and dispersion directions are the same, so a second (static, conventional) grating disperses the spectrum in the orthogonal direction to prevent different wavelengths from “overwriting” each other. Because the streaking is done by the grating, the streaked output spectrum is recorded with a time-integrating device, such as a CCD. System model, typical design, and performance expectations will be presented.

Goldin, F. J.

2012-08-02T23:59:59.000Z

136

Nanograting-based compact vacuum ultraviolet spectrometer and ...  

Nanograting-based compact vacuum ultraviolet spectrometer and beam pro?ler for in situ characterization of high-order harmonic generation light sources

137

The triple axis spectrometer at the new research reactor OPAL ...  

Science Conference Proceedings (OSTI)

... The triple axis spectrometer at the new research reactor OPAL in Australia. ... The TAS will be based on a thermal beam at the reactor face. ...

138

SEQUOIA: the Fine-Resolution Fermi Chopper Spectrometer at SNS...  

NLE Websites -- All DOE Office Websites (Extended Search)

of novel systems and materials that are currently unknown and complements the other main SNS chopper spectrometer, ARCS. In general, SEQUOIA is the instrument of choice for...

139

Passive Millimeter-Wave Spectrometer for Remote Chemical Detection...  

NLE Websites -- All DOE Office Websites (Extended Search)

Media format Windows Media Format - Low Bandwidth Passive Millimeter-Wave Spectrometer for Remote Chemical Detection shown in this movie clip. :: Please wait until video loads...

140

Workshop on Precision Measurements of $\\alpha_s$  

Science Conference Proceedings (OSTI)

These are the proceedings of the Workshop on Precision Measurements of {alpha}{sub s} held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of {alpha}{sub s}(m{sub Z}) in the {ovr MS} scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, {tau}-decays, electro-weak precision observables and Z-decays, event-shapes, and lattice QCD. These proceedings contain a short summary contribution from the speakers, as well as the lists of authors, conveners, participants, and talks.

Bethke, Siegfried; /Munich, Max Planck Inst.; Hoang, Andre H.; /Vienna U.; Kluth, Stefan; /Munich, Max Planck Inst.; Schieck, Jochen; /Munich U.; Stewart, Iain W.; Aoki, S.; Beneke, M.; Bethke, S.; Blumlein, J.; Brambilla, N.; Brodsky, S.; /MIT, LNS

2011-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Brett Parker | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Brett Parker Brett Parker Recent Presentations "BNL Direct Wind Magnets," (pdf) presentation dedicated to the memory of Pat Thompson given at the 22nd Magnet Technology Conference (MT22), September 11 - 16, 2011, Marseille, France A Review of BNL Direct-Wind Superconducting IR Magnet Experience, (pdf) presented at the 30th Advanced ICFA Beam Dynamics Workshop on High Luminosity e+e- Collisions, October 13 - 16, 2003, Stanford, California The Serpentine Coil Design for BEPC-II Superconducting IR Magnets, (pdf) presented at the "Mini-Workshop on BEPC-II IR Design", January 12 - 16, 2004, Beijing, P.R. China Ma nufacture of a Superconducting Octupole Magnet for the ALPHA Experiment at CERN using the Direct Wind Machine Presentations Prior to 2004 Superconducting Final Focus Magnet Issues (pdf), presented at

142

Gamma-ray spectrometer utilizing xenon at high pressure  

SciTech Connect

A prototype gamma-ray spectrometer utilizing xenon gas near the critical point (166{degrees}C, 58 atm) is under development. The spectrometer will function as a room-temperature ionization chamber detecting gamma rays in the energy range 100 keV2 MeV, with an energy resolution intermediate between semiconductor (Ge) and scintillation (NaI) spectrometers. The energy resolution is superior to that of a NaI scintillation spectrometer by a substantial margin (approximately a factor 5), and accordingly, much more information can be extracted from a given gamma-ray spectrum. Unlike germanium detectors, the spectrometer possesses the capability for sustained operation under ambient temperature conditions without a requirement for liquid nitrogen.

Smith, G.C.; Mahler, G.J.; Yu, B.; Kane, W.R. [Brookhaven National Lab., Upton, NY (United States); Markey, J.K. [Yale Univ., New Haven, CT (United States). School of Medicine

1994-08-01T23:59:59.000Z

143

Alpha-nucleus potential for alpha-decay and sub-barrier fusion  

E-Print Network (OSTI)

The set of parameters for alpha-nucleus potential is derived by using the data for both the alpha-decay half-lives and the fusion cross-sections around the barrier for reactions alpha+40Ca, alpha+59Co, alpha+208Pb. The alpha-decay half-lives are obtained in the framework of a cluster model using the WKB approximation. The evaluated alpha-decay half-lives and the fusion cross-sections agreed well with the data. Fusion reactions between alpha-particle and heavy nuclei can be used for both the formation of very heavy nuclei and spectroscopic studies of the formed compound nuclei.

V. Yu. Denisov; H. Ikezoe

2005-10-27T23:59:59.000Z

144

Economic analyses of alpha channeling in tokamak power plants.  

SciTech Connect

The hot-ion-mode of operation [1] has long been thought to offer optimized performance for long-pulse or steady-state magnetic fusion power plants. This concept was revived in recent years when theoretical considerations suggested that nonthermal fusion alpha particles could be made to channel their power density preferentially to the fuel ions [2,3]. This so-called anomalous alpha particle slowing down can create plasmas with fuel ion temperate T{sub i} somewhat larger than the electron temperature T{sub e}, which puts more of the beta-limited plasma pressure into the useful fuel species (rather than non-reacting electrons). As we show here, this perceived benefit may be negligible or nonexistent for tokamaks with steady state current drive. It has likewise been argued [2,3] that alpha channeling could be arranged such that little or no external power would be needed to generate the steady state toroidal current. Under optimistic assumptions we show that such alpha-channeling current drive would moderately improve the economic performance of a first stability tokamak like ARIES-I [4], however a reversed-shear (advanced equilibrium) tokamak would likely not benefit since traditional radio-wave (rf) electron-heating current drive power would already be quite small.

Ehst, D.A.

1998-09-17T23:59:59.000Z

145

PTAX: the Polarized Triple-Axis Spectrometer at HFIR | ORNL Neutron...  

NLE Websites -- All DOE Office Websites (Extended Search)

The Polarized Triple-Axis Spectrometer at HFIR HB-1 photo Polarized Triple-Axis Spectrometer (HB-1). Of the four triple-axis spectrometers installed at HFIR, the HB-1 instrument is...

146

A synopsis of collective alpha effects and implications for ITER  

SciTech Connect

This paper discusses the following: Alpha Interaction with Toroidal Alfven Eigenmodes; Alpha Interaction with Ballooning Modes; Alpha Interaction with Fishbone Oscillations; and Implications for ITER.

Sigmar, D.J.

1990-10-01T23:59:59.000Z

147

Constraining PCP Violating Varying Alpha Theory through Laboratory Experiments  

Science Conference Proceedings (OSTI)

In this report we have studied the implication of a parity and charge-parity (PCP) violating interaction in varying alpha theory. Due to this interaction, the state of photon polarization can change when it passes through a strong background magnetic field. We have calculated the optical rotation and ellipticity of the plane of polarization of an electromagnetic wave and tested our results against different laboratory experiments. Our model contains a PCP violating parameter {beta} and a scale of alpha variation {omega}. By analyzing the laboratory experimental data, we found the most stringent constraints on our model parameters to be 1 {le} {omega} {le} 10{sup 13} GeV{sup 2} and -0.5 {le} {beta} {le} 0.5. We also found that with the existing experimental input parameters it is very difficult to detect the ellipticity in the near future.

Maity, Debaprasad; /NCTS, Taipei /Taiwan, Natl. Taiwan U.; Chen, Pisin; /NCTS, Taipei /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC

2012-06-06T23:59:59.000Z

148

Determination of alpha_s from tau decays  

E-Print Network (OSTI)

Hadronic tau decays offer the possibility of determining the strong coupling alpha_s at relatively low energy. Precisely for this reason, however, good control over the perturbative QCD corrections, the non-perturbative condensate contributions in the framework of the operator product expansion (OPE), as well as the corrections going beyond the OPE, the duality violations (DVs), is required. On the perturbative QCD side, the contour-improved versus fixed-order resummation of the series is still an issue, and will be discussed. Regarding the analysis, self-consistent fits to the data including all theory parameters have to be performed, and this is also explained in some detail. The fit quantities are moment integrals of the tau spectral function data in a certain energy window and care should be taken to have acceptable perturbative behaviour of those moments as well as control over higher-dimensional operator corrections in the OPE.

Jamin, Matthias

2013-01-01T23:59:59.000Z

149

Al(26) Studies with INTEGRAL's Spectrometer SPI  

E-Print Network (OSTI)

Al(26) radioactivity traces recent nucleosynthesis throughout the Galaxy, and is known to be produced in massive stars and novae. The map from its decay gamma-ray line suggests massive stars to dominate, but high-resolution line spectroscopy is expected to supplement imaging of Al(26) source regions and thus to help decide about the Al(26) injection process and interstellar environment, hence about the specific massive-star subgroup and phase which produces interstellar Al(26). The INTEGRAL Spectrometer SPI has observed Galactic Al(26) radioactivity in its 1809 keV gamma-ray line during its first inner-Galaxy survey. Instrumental background lines make analysis difficult; yet, a clear signal from the inner Galaxy agrees with expectations. In particular, SPI has constrained the line width to exclude previously-reported line broadenings corresponding to velocities >500 km/s. The signal-to-background ratio of percent implies that detector response and background modeling need to be fine-tuned to eventually enable line shape deconvolution in order to extract source location information along the line of sight.

R. Diehl; K. Kretschmer; G. Lichti; V. Schönfelder; A. W. Strong; A. von Kienlin; J. Knödlseder; P. Jean; V. Lonjou; G. Weidenspointner; J. -P. Roques; G. Vedrenne; S. Schanne; N. Mowlavi; C. Winkler; C. Wunderer

2004-05-11T23:59:59.000Z

150

Refinement of the $n-\\alpha$ and $p-\\alpha$ fish-bone potential  

E-Print Network (OSTI)

The fishbone potential of composite particles simulates the Pauli effect by nonlocal terms. We determine the $n-\\alpha$ and $p-\\alpha$ fish-bone potential by simultaneously fitting to the experimental phase shifts. We found that with a double Gaussian parametrization of the local potential can describe the $n-\\alpha$ and $p-\\alpha$ phase shifts for all partial waves.

Smith, E; Papp, Z

2012-01-01T23:59:59.000Z

151

Comparison of a transmission grating spectrometer to a reflective grating spectrometer for standoff laser-induced breakdown spectroscopy measurements  

Science Conference Proceedings (OSTI)

We evaluate a new transmission grating spectrometer for standoff laser-induced breakdown spectroscopy (LIBS) measurements. LIBS spectra collected from standoff distances are often weak, with smaller peaks blending into the background and noise. Scattered light inside the spectrometer can also contribute to poor signal-to-background and signal-to-noise ratios for smaller emission peaks. Further, collecting standoff spectra can be difficult because most spectrometers are designed for laboratory environments and not for measurements in the field. To address these issues, a custom-designed small, lightweight transmission grating spectrometer with no moving parts was built that is well suited for standoff LIBS field measurements. The performance of the spectrometer was quantified through 10 m standoff LIBS measurements collected from aluminum alloy samples and measurements from spectra of a Hg-Ar lamp. The measurements were compared to those collected using a Czerny-Turner reflective grating spectrometer that covered a similar spectral range and used the same ICCD camera. Measurements using the transmission grating spectrometer had a 363% improved signal-to-noise ratio when measured using the 669 nm aluminum emission peak.

Weisberg, Arel; Craparo, Joseph; De Saro, Robert; Pawluczyk, Romuald

2010-05-01T23:59:59.000Z

152

Alpha Channeling in a Rotating Plasma  

E-Print Network (OSTI)

The wave-particle alpha-channeling effect is generalized to include rotating plasma. Specifically, radio frequency waves can resonate with alpha particles in a mirror machine with ExB rotation to diffuse the alpha particles along constrained paths in phase space. Of major interest is that the alpha-particle energy, in addition to amplifying the RF waves, can directly enhance the rotation energy which in turn provides additional plasma confinement in centrifugal fusion reactors. An ancillary benefit is the rapid removal of alpha particles, which increases the fusion reactivity.

Fetterman, Abraham J

2008-01-01T23:59:59.000Z

153

BASIS: Backscattering Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Backscattering Spectrometer Backscattering Spectrometer View inside the BAIS tank View inside the BASIS tank. BASIS is a near-backscattering, crystal-analyzer spectrometer that provides very fine energy resolution, as low as 3.0 to 3.5 µeV at the elastic peak (depending on sample size). This requires a long initial guide section of 84 m from moderator to sample in order to achieve the timing resolution necessary for obtaining the desired energy resolution. BASIS provides an excellent dynamic range near the elastic peak of about plus and minus 100 µeV in the standard high-intensity operation regime, which, if needed, could be extended to plus and minus 200 µeV and beyond. The spectrometer is optimized for quasielastic scattering but provides about 0.1% resolution in energy transfers up to ~40 meV; the inelastic excitations need to be

154

The FIRE infrared spectrometer at Magellan: construction and commissioning  

E-Print Network (OSTI)

We describe the construction and commissioning of FIRE, a new 0.8-2.5?m echelle spectrometer for the Magellan/ Baade 6.5 meter telescope. FIRE delivers continuous spectra over its full bandpass with nominal spectral ...

Simcoe, Robert A.

155

Study of electromagnetic processes with the dielectron spectrometer HADES  

Science Conference Proceedings (OSTI)

Dielectron production in pp and dp reactions at 1.25 A.GeV has been studied with the High Acceptance DiElectron Spectrometer (HADES) at GSI. Results obtained in inclusive and exclusive channels are shown

B. Ramstein; The HADES collaboration

2010-01-01T23:59:59.000Z

156

An acousto-optical correlation spectrometer for radio astronomy.  

E-Print Network (OSTI)

??The objective of this thesis research is to develop and construct a wide-band, high resolution, two-channel prototype acousto-optic correlation spectrometer (AOCS) to analyze signals received… (more)

Cheung, Kwok-wai

1987-01-01T23:59:59.000Z

157

On the Lyman-alpha and Lyman-beta lines in solar coronal streamers  

E-Print Network (OSTI)

We investigate the formation of the H I Lyman-alpha and Lyman-beta lines in an equatorial coronal streamer. Particular attention is paid to frequency redistribution for the scattering of the incident radiation. The properties of the spectral lines are studied. The coronal model is given by a global 2.5-D three fluid solar wind model with alpha particles. The emergent intensities and line profiles are calculated from the solution of the statistical equilibrium and radiative transfer equations for an hydrogen atom with 11 energy levels under non local thermodynamic equilibrium. The formation of the lines results from radiative excitation, collisional excitation, and takes into account the coupling with all other transitions between the hydrogen energy levels. We present new estimates of the radiative and collisional contributions of the Lyman line intensities within the streamer. It is also shown that within the streamer, the full width at half-maximum (FWHM) of the Lyman-beta line is a better indicator of the plasma temperature than that of Lyman-alpha. These results show that care should be taken when inferring the proton temperature from the Lyman-alpha line profile as observed in coronal streamers, e.g. by the Ultraviolet Coronagraph Spectrometer or the Solar Ultraviolet Measurements of Emitted Radiation experiments on board the Solar and Heliospheric Observatory.

Nicolas Labrosse; Xing Li; Bo Li

2006-06-05T23:59:59.000Z

158

Experimental investigations of electron capture from atomic hydrogen and deuterium by alpha particles  

DOE Green Energy (OSTI)

We have undertaken a program at the University of Missouri-Rolla to experimentally determine cross sections for ion-atom collisions of interest in fusion reactor development. During the last grant period, we have made measurements of total and singly-differential cross sections for the alpha double-capture reaction. He{sup ++} + He(ls{sup 2}) {yields} He({Sigma}n,{ell}) + He{sup ++}. Collisions of this type have been discussed as a basis for diagnostics in which alphas are neutralized in a single collisions either by a HeI beam or by the ablative cloud from mechanically introduced impurity pellets. We are now finishing measurements of cross sections for the alpha single capture reaction He{sup ++} + He(1s{sup 2}) {yields} He{sup +}(n) + He{sup +}(1s), and propose to study He{sup ++} + H(1s) {yields} He{sup +}(n) + H{sup +} during next year. Accurate knowledge of these cross sections is fundamental for modeling of neutral-hydrogen beam penetration in fusion plasmas as well as for spectroscopic diagnostics of alpha densities and velocity distributions, especially for the case of capture into the n = 4 state of the projectile He{sup +}. Our measurements are made using a unique collision spectrometer discussed in this paper.

Not Available

1990-01-01T23:59:59.000Z

159

Simple Model of the (alpha)(omega) Dynamo: Self-Excited Spheromaks  

Science Conference Proceedings (OSTI)

The astrophysical {alpha}{omega} dynamo converting angular momentum to magnetic energy can be interpreted as a self-excited Faraday dynamo together with magnetic relaxation coupling the dynamo poloidal field to the toroidal field produced by dynamo currents. Since both toroidal and poloidal fields are involved, the system can be modeled as helicity creation and transport, in a spheromak plasma configuration in quasi-equilibrium on the time scale of changes in magnetic energy. Neutral beams or plasma gun injection across field lines could create self-excited spheromaks in the laboratory.

Fowler, T K

2010-01-26T23:59:59.000Z

160

Nielsen-Olesen vortex in varying-alpha theories  

E-Print Network (OSTI)

We consider soliton solutions to Bekenstein's theory, for which the fine structure constant $\\alpha=e^2/(4\\pi\\hbar c)$ is allowed to vary due to the presence of a dielectric field pervading the vacuum. More specifically we investigate the effects of a varying $\\alpha$ upon a complex scalar field with a U(1) electromagnetic gauge symmetry subject to spontaneous symmetry breaking. We find vortex solutions to this theory, similar to the Nielsen-Olesen vortex. Near the vortex core the electric charge is typically much larger than far away from the string, lending these strings a superconducting flavour. In general the dielectric field coats the usual local string with a global string envelope. We discuss the cosmological implications of networks of such strings, with particular emphasis on their ability to generate inhomogeneous recombination scenarios. We also consider the possibility of the dielectric being a charged free field. Even though the vacuum of such a field is trivial, we find that the dielectric arranges itself in the shape of a local string, with a quantized magnetic flux at the core -- presumably borrowing these topological features from the underlying Nielsen-Olesen vortex.

J. Magueijo; H. Sandvik; T. W. B. Kibble

2001-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

magnet technology has allowed physicists to attain higher energies in circular accelerators. One can obtain higher magnetic fields because there is no resistance in a...

162

Hydrogen-Isotope Mass-Spectrometer Evaluation Program. Bimonthly progress report, July/September 1982  

SciTech Connect

The joint SRL-SRP Hydrogen Isotope Mass Spectrometer Evaluation Program was undertaken to: (1) evaluate a prototype hydrogen isotope mass spectrometer that was developed for the Mass Spectrometer Technical Group by VG-Isotopes, Ltd., and (2) obtain sufficient data to permit SRP personnel to specify the mass spectrometes that will be purchased under Schedule 44 Budget Project 81-SR-010 to replace obsolete mass spectrometers in Buildings 232-H and 224-H.

Chastagner, P.; Daves, H.L.; Hess, W.B.

1982-01-01T23:59:59.000Z

163

Beta/alpha continuous air monitor  

DOE Patents (OSTI)

A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

Becker, G.K.; Martz, D.E.

1988-06-27T23:59:59.000Z

164

TAX: Backscattering Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

2 to 100 meV. Typical applications include spin and lattice dynamics in high-temperature superconductors and related compounds; low-dimensional magnetic model systems; magnetic...

165

Available Technologies: Biological Production of Alpha Olefins ...  

APPLICATIONS OF TECHNOLOGY: Production of the following from sugar or starch: alpha olefins including 1-hexene, 1-decene, deca-1,5-diene, aromatic ...

166

SHOE V.1.5 ALPHA  

Energy Science and Technology Software Center (OSTI)

002913MLTPL00 Sandia Higher Order Elements (SHOE) v 0.5 alpha  http://midas3.kitware.com/midas/folder/10328 

167

Search for macroscopic CP violating forces using a neutron EDM spectrometer  

E-Print Network (OSTI)

The search for CP violating forces between nucleons in the so-called axion window of force ranges lam between 2x10^-5 m and 0.02 m is interesting because only little experimental information is available there. Axion-like particles would induce a pseudo-magnetic field for neutrons close to bulk matter. A laboratory search investigates neutron spin precession close to a heavy mirror using ultracold neutrons in a magnetic resonance spectrometer. From the absence of a shift of the magnetic resonance we established new constraints on the coupling strength of axion-like particles in terms of the product gs x gp of scalar and pseudo-scalar dimensionless constants, as a function of the force range lam, gs x gp x lam^2 <= 2x10-21 [cm^2] (C.L.95%) for 10^-4 cm < lam < 1 cm. For 0.1 cm < lam < 1 cm previous limits are improved by 4 to 5 orders of magnitude.

A. P. Serebrov; O. Zimmer; P. Geltenbort; A. K. Fomin; S. N. Ivanov; E. A. Kolomensky; I. A. Krasnoshekova; M. S. Lasakov; V. M. Lobashev; A. N. Pirozhkov; V. E. Varlamov; A. V. Vasiliev; O. M. Zherebtsov; E. B. Aleksandrov; S. P. Dmitriev; N. A. Dovator

2009-12-11T23:59:59.000Z

168

ASSIMILATING DATA INTO AN {alpha}{Omega} DYNAMO MODEL OF THE SUN: A VARIATIONAL APPROACH  

Science Conference Proceedings (OSTI)

We have developed a variational data assimilation technique for the Sun using a toy {alpha}{Omega} dynamo model. The purpose of this work is to apply modern data assimilation techniques to solar data using a physically based model. This work represents the first step toward a complete variational model of solar magnetism. We derive the adjoint {alpha}{Omega} dynamo code and use a minimization procedure to invert the spatial dependence of key physical ingredients of the model. We find that the variational technique is very powerful and leads to encouraging results that will be applied to a more realistic model of the solar dynamo.

Jouve, Laurene [Universite de Toulouse, UPS-OMP, CNRS, IRAP, 31400 Toulouse (France); Brun, Allan Sacha [Laboratoire AIM Paris-Saclay, CEA/IRFU Universite Paris-Diderot CNRS/INSU, 91191 Gif-Sur-Yvette (France); Talagrand, Olivier [Laboratoire de meteorologie dynamique, UMR 8539, Ecole Normale Superieure, Paris Cedex 05 (France)

2011-07-01T23:59:59.000Z

169

ARM - Field Campaign - ASSIST: Atmospheric Sounder Spectrometer for  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsASSIST: Atmospheric Sounder Spectrometer for Infrared govCampaignsASSIST: Atmospheric Sounder Spectrometer for Infrared Spectral Technology Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : ASSIST: Atmospheric Sounder Spectrometer for Infrared Spectral Technology 2008.07.08 - 2008.07.18 Lead Scientist : Michael Howard For data sets, see below. Description Goals of assist were to intercompare radiance spectra and profile retrievals from a new AERI-like instrument, called "ASSIST" with the SGP site AERI(s) and calculations from Radiosondes measurements. * To bring the ASSIST instrument to the SGP ACRF and perform simultaneous measurements of the sky radiation with those from the AERI. * On relatively cloud-free days, release a special radiosonde at the

170

CORELLI: the Elastic Diffuse Scattering Spectrometer at SNS | ORNL Neutron  

NLE Websites -- All DOE Office Websites (Extended Search)

The Elastic Diffuse Scattering Spectrometer The Elastic Diffuse Scattering Spectrometer CORELLI The CORELLI instrument. CORELLI is a statistical chopper spectrometer with energy discrimination. It's designed and optimized to probe complex disorder in crystalline materials through diffuse scattering of single-crystal samples. The momentum transfer ranges from 0.5 to 12 Ã…-1, and the energy of incident neutrons ranges from 10 to 200 meV. This instrument combines the high efficiency of white-beam Laue diffraction with energy discrimination by modulating the beam with a statistical chopper. A cross-correlation method is used to reconstruct the elastic signal from the modulated data. Accurate modeling of the short-range order associated with the diffuse scattering requires measurements over large volumes of three-dimensional reciprocal space, with sufficient momentum

171

Ultracold-neutron infrastructure for the gravitational spectrometer GRANIT  

E-Print Network (OSTI)

The gravitational spectrometer GRANIT will be set up at the Institut Laue Langevin. It will profit from the high ultracold neutron density produced by a dedicated source. A monochromator made of crystals from graphite intercalated with potassium will provide a neutron beam with 0.89 nm incident on the source. The source employs superthermal conversion of cold neutrons in superfluid helium, in a vessel made from BeO ceramics with Be windows. A special extraction technique has been tested which feeds the spectrometer only with neutrons with a vertical velocity component v < 20 cm/s, thus keeping the density in the source high. This new source is expected to provide a density of up to 800 1/cm3 for the spectrometer.

P. Schmidt-Wellenburg; K. H. Andersen; P. Courtois; M. Kreuz; S. Mironov; V. V. Nesvizhevsky; G. Pignol; K. V. Protasov; T. Soldner; F. Vezzu; O. Zimmer

2008-11-11T23:59:59.000Z

172

Photo-Spectrometer Realized In A Standard Cmos Ic Process  

DOE Patents (OSTI)

A spectrometer, comprises: a semiconductor having a silicon substrate, the substrate having integrally formed thereon a plurality of layers forming photo diodes, each of the photo diodes having an independent spectral response to an input spectra within a spectral range of the semiconductor and each of the photo diodes formed only from at least one of the plurality of layers of the semiconductor above the substrate; and, a signal processing circuit for modifying signals from the photo diodes with respective weights, the weighted signals being representative of a specific spectral response. The photo diodes have different junction depths and different polycrystalline silicon and oxide coverings. The signal processing circuit applies the respective weights and sums the weighted signals. In a corresponding method, a spectrometer is manufactured by manipulating only the standard masks, materials and fabrication steps of standard semiconductor processing, and integrating the spectrometer with a signal processing circuit.

Simpson, Michael L. (Knoxville, TN); Ericson, M. Nance (Knoxville, TN); Dress, William B. (Knoxville, TN); Jellison, Gerald E. (Oak Ridge, TN); Sitter, Jr., David N. (Tucson, AZ); Wintenberg, Alan L. (Knoxville, TN)

1999-10-12T23:59:59.000Z

173

Alpha Technologies | Open Energy Information  

Open Energy Info (EERE)

Technologies Technologies Jump to: navigation, search Name Alpha Technologies Place Bellingham, Washington State Zip 98226 Sector Services, Solar Product Bellingham (WA)-based firm offering, among other products, power conversion products designed specifically for the PV market, plus installation services for solar systems. Coordinates 48.75235°, -122.471219° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.75235,"lon":-122.471219,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

174

The Results of Recent MICE Superconducting Spectrometer Solenoid Test  

E-Print Network (OSTI)

Design of Current Leads for the MICE Coupling Magnet,” Proceedings International Conference of Cryogenics and Refrigeration

Green, Michael A

2010-01-01T23:59:59.000Z

175

Bragg x-ray survey spectrometer for ITER  

Science Conference Proceedings (OSTI)

Several potential impurity ions in the ITER plasmas will lead to loss of confined energy through line and continuum emission. For real time monitoring of impurities, a seven channel Bragg x-ray spectrometer (XRCS survey) is considered. This paper presents design and analysis of the spectrometer, including x-ray tracing by the Shadow-XOP code, sensitivity calculations for reference H-mode plasma and neutronics assessment. The XRCS survey performance analysis shows that the ITER measurement requirements of impurity monitoring in 10 ms integration time at the minimum levels for low-Z to high-Z impurity ions can largely be met.

Varshney, S. K.; Jakhar, S. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India); Barnsley, R. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); O'Mullane, M. G. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

2012-10-15T23:59:59.000Z

176

Alpha Channeling in Mirror Machines  

SciTech Connect

Because of their engineering simplicity, high-?, and steady-state operation, mirror machines and related open-trap machines such as gas dynamic traps, are an attractive concept for achieving controlled nuclear fusion. In these open-trap machines, the confinement occurs by means of magnetic mirroring, without the magnetic field lines closing upon themselves within the region of particle confinement. Unfortunately, these concepts have not achieved to date very spectacular laboratory results, and their reactor prospects are dimmed by the prospect of a low Q-factor, the ratio of fusion power produced to auxiliary power. Nonetheless, because of its engineering promise, over the years numerous improvements have been proposed to enhance the reactor prospects of mirror fusion, such as tandem designs, end-plugging, and electric potential barriers.

Fisch N.J.

2005-10-19T23:59:59.000Z

177

Alpha Renewable Energy | Open Energy Information  

Open Energy Info (EERE)

Renewable Energy Renewable Energy Jump to: navigation, search Name Alpha Renewable Energy Place Atlanta, Georgia Sector Biomass Product Manufacturer of biomass wood gas stoves and standalone power generators for rural areas. References Alpha Renewable Energy[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Alpha Renewable Energy is a company located in Atlanta, Georgia . References ↑ "Alpha Renewable Energy" Retrieved from "http://en.openei.org/w/index.php?title=Alpha_Renewable_Energy&oldid=342033" Categories: Clean Energy Organizations Companies Organizations Stubs What links here Related changes Special pages Printable version Permanent link Browse properties

178

Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression  

Science Conference Proceedings (OSTI)

Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

1998-06-29T23:59:59.000Z

179

Acousto-optical correlation spectrometer for radio astronomy  

Science Conference Proceedings (OSTI)

The objective of this thesis is to develop and construct a wide-band, high-resolution, two-channel prototype acousto-optic correlation spectrometer (AOCS) to analyze signals received by the three-element millimeter-wave interferometer at Caltech's Owens Valley Radio Observatory (OVRO), which may be used to study the distribution of carbon monoxide and other molecules in galaxies. The proposed correlation spectrometer has the main advantage of large time-bandwidth products and hence of low cost per frequency channel. Thus, it is suitable for many scientific objectives that require both large bandwidth and high resolution, such as mapping the distribution and temperature of the interstellar gases of galactic sources and extragalactic sources or studying the atmospheric conditions of planets in the solar system. Phase switching has been used to reduce the zero level variation of this instrument, and is found to be more effective than other schemes used by the single dish acousto-optical spectrometers. Both the frequency resolution and the frequency coverage of this instrument can be changed easily, and give it a flexibility not attainable by the filter-bank spectrometers.

Cheung, K.

1987-01-01T23:59:59.000Z

180

Optical system for high resolution spectrometer/monochromator  

DOE Patents (OSTI)

An optical system for use in a spectrometer or monochromator employing a mirror which reflects electromagnetic radiation from a source to converge with same in a plane. A straight grooved, varied-spaced diffraction grating receives the converging electromagnetic radiation from the mirror and produces a spectral image for capture by a detector, target or like receiver.

Hettrick, Michael C. (Berkeley, CA); Underwood, James H. (Walnut Creek, CA)

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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181

BRAHMS: Conceptual design report. Forward angle and midrapidity hadron spectrometers at RHIC  

SciTech Connect

The Broad RAnge Hadron Magnetic Spectrometers experiment (BRAHMS) is designed to measure charged hadrons over a wide range of rapidity and transverse momentum for all available beams and energies. This conceptual design report describes the BRAHMS detector and how it will be installed and operated at RHIC. Chapter 2 presents an overview of the physics program to be achieved with the BRAHMS Experiment. This is followed in Chapter 3 by an overview of the detector systems, a description which is close to earlier designs but changed to reflect updates. The magnet design is reviewed in Chapter 4. Chapter 5 describes the requirements that the BRAHMS Experiment sets for the intersection region. The arguments for the proposed positioning of the two magnet arms are presented. The needed support buildings and their possible placements are discussed. Chapter 6 examines the requirements on the elements of the forward arm, and demonstrates the feasibility of the proposed combination of magnets and tracking detectors. Most of the detectors are small TPC`s, and several features of a prototoye TPC and the testing thereof are describes. The particle identification in BRAHMS is achieved by time-of-flight techniques and Cerenkov counters. This is describes in Chapter 7. The global detectors, i.e., the beam-beam counters and the multiplicity detector, are described next in Chapter 8. The concept for a centrality detector based on silicon strips is presented; a backup scheme employs an array of proportional gas counters. Considerations on data aquisition and triggers, as given next in Chapter 9, are fairly conventional and shoud not pose any major problems for development. The cost estimate for the experiment is given last; the total budget for BRAHMS is within the original goal.

BRAHMS Collaboration

1995-07-01T23:59:59.000Z

182

Alpha-Particle Condensation in Nuclear Systems  

E-Print Network (OSTI)

The onset of quartetting, i.e. alpha-particle condensation, in symmetric nuclear matter is studied with the help of an in-medium modified four nucleon equation. It is found that at very low density quartetting wins over pairing, because of the strong binding of the alpha-particles. The critical temperature can reach values up to around 6 MeV. Also the disappearance of alpha-particles with increasing density, i.e. the Mott transition, is investigated. In finite nuclei the Hoyle state, that is the 0_2^+ of 12C, is identified as an "alpha-particle condensate" state. It is conjectured that such states also exist in heavier n alpha-nuclei, like 16O, 20Ne, etc. For instance the 6-th 0^+ state of 16O at 15.1 MeV is identified from a theoretical analysis as being a strong candidate for an alpha condensate state. Exploratory calculations are performed for the density dependence of the alpha condensate fraction at zero temperature to address the suppression of the four-particle condensate below nuclear-matter density. Possible quartet condensation in other systems is discussed briefly

Y. Funaki; T. Yamada; H. Horiuchi; G. Röpke; P. Schuck; A. Tohsaki

2008-09-03T23:59:59.000Z

183

Magnetic Storms  

Science Conference Proceedings (OSTI)

... magnetic reversal. As there is no predictive science of geomagnetism, we currently lack even simple forecasts. Our scientific ...

2010-10-05T23:59:59.000Z

184

Magnetic Imaging  

Science Conference Proceedings (OSTI)

... data-storage and permanent magnets with increased energy products, in ... Optimization of future materials, including improved yields, requires an ...

2012-10-02T23:59:59.000Z

185

Magnetic Properties  

Science Conference Proceedings (OSTI)

...Since the discovery of high-temperature superconductors in 1986 (Ref 10), the demonstration of magnetic flux exclusion

186

Alpha Energy formerly Altair Energy | Open Energy Information  

Open Energy Info (EERE)

Washington State . References "Alpha Energy (formerly Altair Energy)" Retrieved from "http:en.openei.orgwindex.php?titleAlphaEnergyformerlyAltairEnergy&oldid342032...

187

Improvements of Droplet Size Distribution Measurements with the Fast-FSSP (Forward Scattering Spectrometer Probe)  

Science Conference Proceedings (OSTI)

The basics of single particle measurements are discussed and illustrated with measurements of the droplet size distribution with an optical spectrometer, the Forward Scattering Spectrometer Probe (FSSP), and its improved version, the Fast-FSSP. ...

Jean-Louis Brenguier; Thierry Bourrianne; Afraniode Araujo Coelho; Jacques Isbert; Robert Peytavi; Dominique Trevarin; Perry Weschler

1998-10-01T23:59:59.000Z

188

A Microdrop Generator for the Calibration of a Water Vapor Isotope Ratio Spectrometer  

Science Conference Proceedings (OSTI)

A microdrop generator is described that produces water vapor with a known isotopic composition and volume mixing ratio for the calibration of a near-infrared diode laser water isotope ratio spectrometer. The spectrometer is designed to measure in ...

Rosario Q. Iannone; Daniele Romanini; Samir Kassi; Harro A. J. Meijer; Erik R. Th Kerstel

2009-07-01T23:59:59.000Z

189

Design and operation of the wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source  

Science Conference Proceedings (OSTI)

The wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source (SNS) is optimized to provide a high neutron flux at the sample position with a large solid angle of detector coverage. The instrument incorporates modern neutron instrumentation, such as an elliptically focused neutron guide, high speed magnetic bearing choppers, and a massive array of {sup 3}He linear position sensitive detectors. Novel features of the spectrometer include the use of a large gate valve between the sample and detector vacuum chambers and the placement of the detectors within the vacuum, both of which provide a window-free final flight path to minimize background scattering while allowing rapid changing of the sample and sample environment equipment. ARCS views the SNS decoupled ambient temperature water moderator, using neutrons with incident energy typically in the range from 15 to 1500 meV. This range, coupled with the large detector coverage, allows a wide variety of studies of excitations in condensed matter, such as lattice dynamics and magnetism, in both powder and single-crystal samples. Comparisons of early results to both analytical and Monte Carlo simulation of the instrument performance demonstrate that the instrument is operating as expected and its neutronic performance is understood. ARCS is currently in the SNS user program and continues to improve its scientific productivity by incorporating new instrumentation to increase the range of science covered and improve its effectiveness in data collection.

Abernathy, D. L.; Stone, M. B.; Loguillo, M. J.; Lucas, M. S.; Delaire, O. [Neutron Scattering Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831 (United States); Tang, X.; Lin, J. Y. Y.; Fultz, B. [California Institute of Technology, W. M. Keck Laboratory 138-78, Pasadena, California 91125 (United States)

2012-01-15T23:59:59.000Z

190

Design and operation of the wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source  

Science Conference Proceedings (OSTI)

The wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source (SNS) is optimized to provide a high neutron flux at the sample position with a large solid angle of detector coverage. The instrument incorporates modern neutron instrumentation, such as an elliptically-focused neutron guide, high speed magnetic bearing choppers and a massive array of 3He linear position sensitive detectors. Novel features of the spectrometer include the use of a large gate valve between the sample and detector vacuum chambers and the placement of the detectors within the vacuum, both of which provide a window-free final flight path to minimize background scattering while allowing rapid changing of the sample and sample environment equipment. ARCS views the SNS decoupled ambient temperature water moderator, using neutrons with incident energy typically in the range from 15 to 1500 meV. This range, coupled with the large detector coverage, allows a wide variety of studies of excitations in condensed matter, such as lattice dynamics and magnetism, in both powder and single-crystal samples. Comparisons of early results to both analytical and Monte Carlo simulation of the instrument performance demonstrate that the instrument is operating as expected and its neutronic performance is understood. ARCS is currently in the SNS user program, and continues to improve its scientific productivity by incorporating new instrumentation to increase the range of science covered and improve its effectiveness in data collection.

Abernathy, Douglas L [ORNL; Stone, Matthew B [ORNL; Loguillo, Mark [ORNL; Lucas, Matthew [Air Force Research Laboratory, Wright-Patterson AFB, OH; Delaire, Olivier A [ORNL; Tang, Xiaoli [California Institute of Technology, Pasadena; Lin, J. Y. Y. [California Institute of Technology, Pasadena; Fultz, B. [California Institute of Technology, Pasadena

2012-01-01T23:59:59.000Z

191

SEQUOIA: the Fine-Resolution Fermi Chopper Spectrometer at SNS...  

NLE Websites -- All DOE Office Websites (Extended Search)

areas such as the following: strongly correlated electrons systems high-temperature superconductors colossal magnetoresistive materials quantum and molecular magnetism...

192

MAGNETIC ENERGY SPECTRA IN SOLAR ACTIVE REGIONS  

SciTech Connect

Line-of-sight magnetograms for 217 active regions (ARs) with different flare rates observed at the solar disk center from 1997 January until 2006 December are utilized to study the turbulence regime and its relationship to flare productivity. Data from the SOHO/MDI instrument recorded in the high-resolution mode and data from the BBSO magnetograph were used. The turbulence regime was probed via magnetic energy spectra and magnetic dissipation spectra. We found steeper energy spectra for ARs with higher flare productivity. We also report that both the power index, {alpha}, of the energy spectrum, E(k) {approx} k{sup -}{alpha}, and the total spectral energy, W = {integral}E(k)dk, are comparably correlated with the flare index, A, of an AR. The correlations are found to be stronger than those found between the flare index and the total unsigned flux. The flare index for an AR can be estimated based on measurements of {alpha} and W as A = 10{sup b}({alpha}W){sup c}, with b = -7.92 {+-} 0.58 and c = 1.85 {+-} 0.13. We found that the regime of the fully developed turbulence occurs in decaying ARs and in emerging ARs (at the very early stage of emergence). Well-developed ARs display underdeveloped turbulence with strong magnetic dissipation at all scales.

Abramenko, Valentyna; Yurchyshyn, Vasyl [Big Bear Solar Observatory, 40386 N. Shore Lane, Big Bear City, CA 92314 (United States)

2010-09-01T23:59:59.000Z

193

Gold Coated Lanthanide Phosphate Nanoparticles for Targeted Alpha Generator Radiotherapy  

Science Conference Proceedings (OSTI)

Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo generators such as 225Ac, which emits four particles in its decay chain, can significantly amplify the radiation dose delivered to the target site. However, renal dose from unbound 213Bi escaping during the decay process limits the dose of 225Ac that can be administered. Traditional chelating moieties are unable to sequester the radioactive daughters because of the high recoil energy from alpha particle emission. To counter this, we demonstrate that an engineered multilayered nanoparticle-antibody conjugate can both deliver radiation and contain the decay daughters of the in vivo -generator 225Ac while targeting biologically relevant receptors. These multi-shell nanoparticles combine the radiation resistance of crystalline lanthanide phosphate to encapsulate and contain 225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established surface chemistry of gold for attachment of nanoparticles to targeting antibodies.

McLaughlin, Mark F [ORNL; Woodward, Jonathan [ORNL; Boll, Rose Ann [ORNL; Wall, Jonathan [University of Tennessee, Knoxville (UTK); Rondinone, Adam Justin [ORNL; Kennel, Steve J [ORNL; Mirzadeh, Saed [ORNL; Robertson, David J. [University of Missouri

2013-01-01T23:59:59.000Z

194

Stability of Relativistic Matter with Magnetic Fields for Nuclear Charges up to the Critical Value  

E-Print Network (OSTI)

We give a proof of stability of relativistic matter with magnetic fields all the way up to the critical value of the nuclear charge $Z\\alpha=2/\\pi$.

Rupert L. Frank; Elliott H. Lieb; Robert Seiringer

2006-10-24T23:59:59.000Z

195

How well do time-integrated K{sub {alpha}} images represent hot electron spatial distributions?  

SciTech Connect

A computational study is described, which addresses how well spatially resolved time-integrated K{sub {alpha}} images recorded in intense laser-plasma experiments correlate with the distribution of ''hot'' (>1 MeV) electrons as they propagate through the target. The hot electron angular distribution leaving the laser-plasma region is critically important for many applications such as Fast Ignition or laser based x-ray sources; and K{sub {alpha}} images are commonly used as a diagnostic. It is found that K{sub {alpha}} images can easily mislead due to refluxing and other effects. Using the particle-in-cell code LSP, it is shown that a K{sub {alpha}} image is not solely determined by the initial population of forward directed hot electrons, but rather also depends upon ''delayed'' hot electrons, and in fact continues to evolve long after the end of the laser interaction. Of particular note, there is a population of hot electrons created during the laser-plasma interaction that acquire a velocity direction opposite that of the laser and subsequently reflux off the front surface of the target, deflect when they encounter magnetic fields in the laser-plasma region, and then traverse the target in a wide spatial distribution. These delayed fast electrons create significant features in the K{sub {alpha}} time-integrated images. Electrons refluxing from the sides and the back of the target are also found to play a significant role in forming the final K{alpha} image. The relative contribution of these processes is found to vary depending on depth within target. These effects make efforts to find simple correlations between K{alpha} images and, for example, Fast Ignition relevant parameters prone to error. Suggestions for future target design are provided.

Ovchinnikov, V. M.; Kemp, G. E.; Schumacher, D. W.; Freeman, R. R.; Van Woerkom, L. D. [Physics Department, Ohio State University, Columbus, Ohio 43210 (United States)

2011-07-15T23:59:59.000Z

196

Nuclear diagnostic for fast alpha particles  

DOE Patents (OSTI)

This invention relates generally to high energy confined plasmas and more particularly is directed to measuring the velocity distribution of confined energetic alpha particles resulting from deuterium-tritium fusion reactions in a confined energetic plasma.

Grisham, L.R.; Post, D.E. Jr.; Dawson, J.M.

1983-11-23T23:59:59.000Z

197

Alpha-beta radiation detector  

DOE Patents (OSTI)

The invention is based in part on the discovery that a plastic housing that is lightweight is surprisingly efficient inasmuch as background signals from any gamma radiation are significantly reduced by using a plastic housing instead of a metal housing. A further aspect of the present invention is the profile of the housing as a bi-linear approximation to a parabola resulting in full optical response from any location on the scintillation material to the photomultiplier tube. A yet further aspect of the present invention is that the survey probe is resistant to magnetic fields. A yet further aspect of the present invention is the use of a snap-fit retaining bracket that overcomes the need for multiple screws.

Fleming, Dale M. (Richland, WA); Simmons, Kevin L. (Kennewick, WA); Froelich, Thomas J. (West Richland, WA); Carter, Gregory L. (Richland, WA)

1998-01-01T23:59:59.000Z

198

Measurements of alpha_s from hadronic event shapes in e+e- annihilation  

E-Print Network (OSTI)

New studies of hadronic event shape observables in e+ e- collisions between 13 and 183 GeV CM energy have enabled the running of alpha_s to be confirmed and the validity of non-perturbative power-law corrections to be investigated. A more precise value of alpha_s(M_Z) with reduced theoretical errors has been reported from fitting 18 oriented event shape distributions measured in one experiment at the Z.

J. C. Thompson

1998-12-02T23:59:59.000Z

199

Methods for the synthesis and polymerization of .alpha.,.alpha.'-dihalo-p-xylenes  

DOE Patents (OSTI)

The present invention describes an improved method for the polymerization of .alpha.,.alpha.-dihalo-p-xylene's such as the .alpha.,.alpha.'-dihalo-2-methoxy-5-(2-ethylhexyloxy)-xylene's. The procedure for synthesis is based on the specific order of addition of reagents and the use of an anionic initiator that allows control of the molecular weight of the polymer. The molecular weight control allows processability of the polymer which is important for its utility in applications including in light-emitting-diodes, field effect transistors and photovoltaic devices.

Ferraris, John P. (Coppell, TX); Neef, Charles J. (Garland, TX)

2002-07-30T23:59:59.000Z

200

ARM - Evaluation Product - Airborne Visible/Infrared Imaging Spectrometer  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsAirborne Visible/Infrared Imaging ProductsAirborne Visible/Infrared Imaging Spectrometer (AVIRIS) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) 1997.08.01 - 1997.08.01 Site(s) SGP General Description AVIRIS is an optical sensor that delivers calibrated images of the upwelling spectral radiance in 224 contiguous spectral channels (bands) with wavelengths from 400 to 2500 nanometers. AVIRIS has been flown on two aircraft platforms: a NASA ER-2 jet and the Twin Otter turboprop. The main objective of the AVIRIS project is to identify, measure, and monitor constituents of the Earth's surface and atmosphere based on molecular absorption and particle scattering signatures. Research with

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Analysis and System Design Framework for Infrared Spatial Heterodyne Spectrometers  

SciTech Connect

The authors present a preliminary analysis and design framework developed for the evaluation and optimization of infrared, Imaging Spatial Heterodyne Spectrometer (SHS) electro-optic systems. Commensurate with conventional interferometric spectrometers, SHS modeling requires an integrated analysis environment for rigorous evaluation of system error propagation due to detection process, detection noise, system motion, retrieval algorithm and calibration algorithm. The analysis tools provide for optimization of critical system parameters and components including : (1) optical aperture, f-number, and spectral transmission, (2) SHS interferometer grating and Littrow parameters, and (3) image plane requirements as well as cold shield, optical filtering, and focal-plane dimensions, pixel dimensions and quantum efficiency, (4) SHS spatial and temporal sampling parameters, and (5) retrieval and calibration algorithm issues.

Cooke, B.J.; Smith, B.W.; Laubscher, B.E.; Villeneuve, P.V.; Briles, S.D.

1999-04-05T23:59:59.000Z

202

Continuous sampling ion mobility spectrometers and methods therefor  

SciTech Connect

An ion mobility spectrometer may include a flow channel having an inlet end and an outlet end. A deflection electrode is positioned within the flow channel so that a non-linear electric field is created between at least a portion of the flow channel and at least a portion of the deflection electrode when an electrostatic potential is placed across the deflection electrode and the flow channel. The ion mobility spectrometer also includes means for producing ions at a position upstream from the leading edge of the deflection electrode, so that ions produced thereby are deflected by the deflection electrode into the non-linear electric field. A detector positioned within the flow channel for detects ions from the non-linear electric field.

Dahl, David A. (Idaho Falls, ID); Scott, Jill R. (Idaho Falls, ID); Appelhans, Anthony D. (Idaho Falls, ID); McJunkin, Timothy R. (Idaho Falls, ID); Olson, John E. (Rigby, ID)

2009-04-14T23:59:59.000Z

203

Ion mobility spectrometers and methods for ion mobility spectrometry  

SciTech Connect

An ion mobility spectrometer may include an inner electrode and an outer electrode arranged so that at least a portion of the outer electrode surrounds at least a portion of the inner electrode and defines a drift space therebetween. The inner and outer electrodes are electrically insulated from one another so that a non-linear electric field is created in the drift space when an electric potential is placed on the inner and outer electrodes. An ion source operatively associated with the ion mobility spectrometer releases ions to the drift space defined between the inner and outer electrodes. A detector operatively associated with at least a portion of the outer electrode detects ions from the drift space.

Dahl, David A. (Idaho Falls, ID); Scott, Jill R. (Idaho Falls, ID); Appelhans, Anthony D. (Idaho Falls, ID); McJunkin, Timothy R. (Idaho Falls, ID); Olson, John E. (Rigby, ID)

2009-04-14T23:59:59.000Z

204

Commissioning of the ATLAS Muon Spectrometer with Cosmic Rays  

E-Print Network (OSTI)

The ATLAS detector at the Large Hadron Collider has collected several hundred million cosmic ray events during 2008 and 2009. These data were used to commission the Muon Spectrometer and to study the performance of the trigger and tracking chambers, their alignment, the detector control system, the data acquisition and the analysis programs. We present the performance in the relevant parameters that determine the quality of the muon measurement. We discuss the single element efficiency, resolution and noise rates, the calibration method of the detector response and of the alignment system, the track reconstruction efficiency and the momentum measurement. The results show that the detector is close to the design performance and that the Muon Spectrometer is ready to detect muons produced in high energy proton-proton collisions.

The ATLAS Collaboration

2010-06-22T23:59:59.000Z

205

Time-of-flight direct recoil ion scattering spectrometer  

DOE Patents (OSTI)

A time of flight direct recoil and ion scattering spectrometer beam line (10). The beam line (10) includes an ion source (12) which injects ions into pulse deflection regions (14) and (16) separated by a drift space (18). A final optics stage includes an ion lens and deflection plate assembly (22). The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions (14) and (16).

Krauss, Alan R. (Naperville, IL); Gruen, Dieter M. (Downers Grove, IL); Lamich, George J. (Orland Park, IL)

1994-01-01T23:59:59.000Z

206

Polarization Measurements in Photoproduction with CEBAF Large Acceptance Spectrometer  

Science Conference Proceedings (OSTI)

A significant part of the experimental program in Hall-B of the Jefferson Lab is dedicated to the studies of the structure of baryons. CEBAF Large Acceptance Spectrometer (CLAS), availability of circularly and linearly polarized photon beams and recent addition of polarized targets provides remarkable opportunity for single, double and in some cases triple polarization measurements in photoproduction. An overview of the experiments will be presented.

E. Pasyuk

2010-05-01T23:59:59.000Z

207

Characterization of a New Lead Slowing Down Spectrometer  

Science Conference Proceedings (OSTI)

There is considerable interest in developing direct measurement methods to determine the plutonium content of spent nuclear fuel within a fuel assembly. One technique that may prove successful is lead slowing-down spectroscopy. Lead Slowing Down Spectroscopy (LSDS) has been used for decades to make cross-section measurements on relatively small isotopic samples of well know masses. For spent fuel assembly measurements, LSDS will be applied in reverse; unknown masses will be determined using well-know cross-sections. In the LSDS, a pulse of neutrons (on the order of 10-100 MeV) is injected into a large lead stack (~ 1m3). The neutrons quickly down-scatter but exhibit little spread in energy about the average, continually-decreasing neutron energy making for a strong correlation between the elapsed time from the initial pulse and the average energy of the neutron. By measuring this elapsed time, it is possible to measure interactions of the neutrons with the fuel in the 0.1 to 1,000 eV range. Many of the actinides have strong resonances in this region, making it possible, through careful measurements and analysis, to extract isotopic masses from LSDS measurements. Pacific Northwest National Laboratory is actively conducting research on both LSDS measurement and data analysis techniques. This paper will present results of the effort to construct and characterize a new lead slowing down spectrometer. The spectrometer was designed to begin testing both experimental measurement and data analysis techniques for determining the plutonium content of spent fuel. To characterize the spectrometer, a series of (n,?) experiments were conducted to measure the correlation between the time after the neutrons enter the lead and the energy of the interaction. Results from these measurements as well as plans for future development of the spectrometer will be discussed.

Casella, Andrew M.; Warren, Glen A.; Cantaloub, Michael G.; Mace, Emily K.; McDonald, Benjamin S.; Overman, Cory T.; Pratt, Sharon L.; Smith, Leon E.; Stave, Sean C.; Wittman, Richard S.

2011-10-01T23:59:59.000Z

208

Compact Refractive Imaging Spectrometer Designs Utilizing Immersed Gratings  

DOE Patents (OSTI)

A compact imaging spectrometer comprising an entrance slit for directing light, a first means for receiving the light and focusing the light, an immersed diffraction grating that receives the light from the first means and defracts the light, a second means for receiving the light from the immersed diffraction grating and focusing the light, and an image plane that receives the light from the second means

Lerner, Scott A. (Livermore, CA); Bennett, Charles L. (Livermore, CA); Bixler, Jay V. (Oakland, CA); Kuzmenko, Paul J. (Livermore, CA); Lewis, Isabella T. (San Jose, CA)

2005-07-26T23:59:59.000Z

209

Design of a Moderated Multidetector Neutron Spectrometer for Optimal Specificity  

Science Conference Proceedings (OSTI)

Neutron spectrometry can play an important role in the detection and identification of neutron-emitting sources in various security applications. In the present work, a portable filtered array neutron spectrometer, consisting of twelve 6LiF-based thermal neutron detectors embedded within a single heterogeneous volume was designed and its expected performance compared to that of a commercially available 12-sphere Bonner spheres spectrometer. Each detector within the volume was designed to optimally respond to a unique portion of the neutron spectrum by varying the type and thickness of materials used to filter the spectrum as well as the thickness of the moderator in front of the detector. The available design space was permuted and performance metrics developed to identify the optimal geometries. The top performing detector geometries were then combinatorially explored to identify the best array of geometries that yielded the most information about a neutron spectrum. The best performing filtered array was found to provide as much spectral information as, or more than, the commercially available 12-sphere Bonner spheres spectrometer to which it was compared.

Harrison, Mark J [ORNL; Cherel, Quentin [University of Florida, Gainesville; Monterial, Mateusz [ORNL

2011-01-01T23:59:59.000Z

210

A multi-crystal wavelength dispersive x-ray spectrometer  

Science Conference Proceedings (OSTI)

A multi-crystal wavelength dispersive hard x-ray spectrometer with high-energy resolution and large solid angle collection is described. The instrument is specifically designed for time-resolved applications of x-ray emission spectroscopy (XES) and x-ray Raman scattering (XRS) at X-ray Free Electron Lasers (XFEL) and synchrotron radiation facilities. It also simplifies resonant inelastic x-ray scattering (RIXS) studies of the whole 2d RIXS plane. The spectrometer is based on the Von Hamos geometry. This dispersive setup enables an XES or XRS spectrum to be measured in a single-shot mode, overcoming the scanning needs of the Rowland circle spectrometers. In conjunction with the XFEL temporal profile and high-flux, it is a powerful tool for studying the dynamics of time-dependent systems. Photo-induced processes and fast catalytic reaction kinetics, ranging from femtoseconds to milliseconds, will be resolvable in a wide array of systems circumventing radiation damage.

Alonso-Mori, Roberto; Montanez, Paul; Delor, James; Bergmann, Uwe [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Kern, Jan [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States); Sokaras, Dimosthenis; Weng, Tsu-Chien; Nordlund, Dennis [SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Tran, Rosalie; Yachandra, Vittal K.; Yano, Junko [Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States)

2012-07-15T23:59:59.000Z

211

The Large Area Lyman Alpha Survey  

E-Print Network (OSTI)

The Lyman-$\\alpha$ line is expected to be strong in the presence of active star formation and the absence of dust, making it a good tool for finding chemically primitive galaxies in the early universe. We report on a new survey for high redshift Lyman-$\\alpha$ sources, the Large Area Lyman Alpha (LALA) survey. Our survey achieves an unprecedented combination of volume and sensitivity by using narrow-band filters on the new $8192^2$ pixel CCD Mosaic Camera at the 4 meter Mayall telescope of Kitt Peak National Observatory. Well-detected sources with flux and equivalent width matching known high redshift Lyman-$\\alpha$ galaxies have an observed surface density corresponding to $11000 \\pm 700$ per square degree per unit redshift at $z=4.5$. Early spectroscopic followup from the Keck telescope suggests that $\\sim 1/3$ of these are actually at $z\\approx 4.5$, and has confirmed five $z > 4$ Lyman-$\\alpha$ emitters so far. Combining our photometric survey with spectroscopic results, we estimate a net density of $\\sim 4000 $ Lyman-$\\alpha$ emitters per square degree per unit redshift at $z\\approx 4.5$. The star formation rate density (estimated both from UV continuum and from line emission) is comparable to that of the Lyman break galaxy population within present uncertainties. The most extreme Lyman-$\\alpha$ emitters in our sample have rest frame equivalent widths $> 100\\AA$, consistent with the expectations for the first burst of star formation in a primitive, dust-free galaxy.

James E. Rhoads; Sangeeta Malhotra; Arjun Dey; Buell T. Jannuzi; Daniel Stern; Hyron Spinrad

2001-04-18T23:59:59.000Z

212

Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Extreme magnetic fields (>2 tesla), especially when combined with temperature, are being shown to revolutionize materials processing and ...

213

Review on the determination of alpha_s from the QCD static energy  

E-Print Network (OSTI)

We review the determination of the strong coupling alpha_s from the comparison of the perturbative expression for the Quantum Chromodynamics static energy with lattice data. We collect here all the perturbative expressions needed to evaluate the static energy at the currently known accuracy.

Tormo, Xavier Garcia i

2013-01-01T23:59:59.000Z

214

The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF  

E-Print Network (OSTI)

and the NIF D. T. Casey, J. A. Frenje, M. Gatu Johnson, F. H. Séguin, C. K. Li et al. Citation: Rev. Sci for measurements of the absolute neutron spectrum at OMEGA and the NIF D. T. Casey,1,a) J. A. Frenje,1 M. Gatu used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute

215

ALPHA ATTENUATION DUE TO DUST LOADING  

SciTech Connect

Previous studies had been done in order to show the attenuation of alpha particles in filter media. These studies provided an accurate correction for this attenuation, but there had not yet been a study with sufficient results to properly correct for attenuation due to dust loading on the filters. At the Savannah River Site, filter samples are corrected for attenuation due to dust loading at 20%. Depending on the facility the filter comes from and the duration of the sampling period, the proper correction factor may vary. The objective of this study was to determine self-absorption curves for each of three counting instruments. Prior work indicated significant decreases in alpha count rate (as much as 38%) due to dust loading, especially on filters from facilities where sampling takes place over long intervals. The alpha count rate decreased because of a decrease in the energy of the alpha. The study performed resulted in a set of alpha absorption curves for each of three detectors. This study also took into account the affects of the geometry differences in the different counting equipment used.

Dailey, A; Dennis Hadlock, D

2007-08-09T23:59:59.000Z

216

The Large Area Lyman Alpha Survey  

E-Print Network (OSTI)

The Lyman-$\\alpha$ line is expected to be strong in the presence of active star formation and the absence of dust, making it a good tool for finding chemically primitive galaxies in the early universe. We report on a new survey for high redshift Lyman-$\\alpha$ sources, the Large Area Lyman Alpha (LALA) survey. Our survey achieves an unprecedented combination of volume and sensitivity by using narrow-band filters on the new $8192^2$ pixel CCD Mosaic Camera at the 4 meter Mayall telescope of Kitt Peak National Observatory. Well-detected sources with flux and equivalent width matching known high redshift Lyman-$\\alpha$ galaxies have an observed surface density corresponding to $11000 \\pm 700$ per square degree per unit redshift at $z=4.5$. Early spectroscopic followup from the Keck telescope suggests that $\\sim 1/3$ of these are actually at $z\\approx 4.5$, and has confirmed five $z > 4$ Lyman-$\\alpha$ emitters so far. Combining our photometric survey with spectroscopic results, we estimate a net density of $\\sim...

Rhoads, J E; Dey, A; Jannuzi, B T; Stern, D; Spinrad, H; Rhoads, James E.; Malhotra, Sangeeta; Dey, Arjun; Jannuzi, Buell T.; Stern, Daniel

2001-01-01T23:59:59.000Z

217

Lyman-alpha Emission from Structure Formation  

E-Print Network (OSTI)

The nature of the interaction between galaxies and the intergalactic medium (IGM) is one of the most fundamental problems in astrophysics. The accretion of gas onto galaxies provides fuel for star formation, while galactic winds transform the nearby IGM in a number of ways. One exciting technique to study this gas is through the imaging of hydrogen Lyman-alpha emission. We use cosmological simulations to study the Lyman-alpha signals expected from the growth of cosmic structure from z=0-5. We show that if dust absorption is negligible, recombinations following the absorption of stellar ionizing photons dominate the total Lyman-alpha photon production rate. However, galaxies are also surrounded by "Lyman-alpha coronae" of diffuse IGM gas. These coronae are composed of a combination of accreting gas and material ejected from the central galaxy by winds. The Lyman-alpha emission from this phase is powered by a combination of gravitational processes and the photoionizing background. While the former dominates at ...

Furlanetto, S; Springel, V; Hernquist, L; Furlanetto, Steven; Schaye, Joop; Springel, Volker; Hernquist, Lars

2004-01-01T23:59:59.000Z

218

Alpha decay favoured isotopes of some superheavy nuclei: Spontaneous fission versus alpha decay  

E-Print Network (OSTI)

Spontaneous fission and alpha decay are the main decay modes for superheavy nuclei. The superheavy nuclei which have small alpha decay half-life compared to spontaneous fission half-life will survive fission and can be detected in the laboratory through alpha decay. We have studied the alpha decay half-life and spontaneous half-life of some superheavy elements in the atomic range Z = 100-130. Spontaneous fission half-lives of superheavy nuclei have been calculated using the phenomenological formula and the alpha decay half-lives using Viola-Seaborg-Sobiczewski formula (Sobiczewski et al. 1989), semi empirical relation of Brown (1992) and formula based on generalized liquid drop model proposed by Dasgupta-Schubert and Reyes (2007). The results are reported here.

O. V. Kiren; S. B. Gudennavar; S. G. Bubbly

2013-01-09T23:59:59.000Z

219

AlphaWatt Ltd | Open Energy Information  

Open Energy Info (EERE)

AlphaWatt Ltd AlphaWatt Ltd Jump to: navigation, search Name AlphaWatt Ltd Place London, United Kingdom Zip EC1V 4PY Sector Solar Product Solar project developer, plans to become an independent power provider. Coordinates 51.506325°, -0.127144° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":51.506325,"lon":-0.127144,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

220

Alternating current long range alpha particle detector  

DOE Patents (OSTI)

An alpha particle detector, utilizing alternating currents, which is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.

MacArthur, D.W.; McAtee, J.L.

1993-02-16T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Lyman-alpha Emission from Structure Formation  

E-Print Network (OSTI)

The nature of the interaction between galaxies and the intergalactic medium (IGM) is one of the most fundamental problems in astrophysics. The accretion of gas onto galaxies provides fuel for star formation, while galactic winds transform the nearby IGM in a number of ways. One exciting technique to study this gas is through the imaging of hydrogen Lyman-alpha emission. We use cosmological simulations to study the Lyman-alpha signals expected from the growth of cosmic structure from z=0-5. We show that if dust absorption is negligible, recombinations following the absorption of stellar ionizing photons dominate the total Lyman-alpha photon production rate. However, galaxies are also surrounded by "Lyman-alpha coronae" of diffuse IGM gas. These coronae are composed of a combination of accreting gas and material ejected from the central galaxy by winds. The Lyman-alpha emission from this phase is powered by a combination of gravitational processes and the photoionizing background. While the former dominates at z~0, collisional excitation following photo-heating may well dominate the total emission at higher redshifts. The central regions of these systems are dense enough to shield themselves from the metagalactic ionizing background; unfortunately, in this regime our simulations are no longer reliable. We therefore consider several scenarios for the emission from the central cores, including one in which self-shielded gas does not emit at all. We show that the combination of star formation and cooling IGM gas can explain most of the observed "Lyman-alpha blobs" at z~3, with the important exception of the largest sources. On the other hand, except under the most optimistic assumptions, cooling IGM gas cannot explain the observations on its own.

Steven Furlanetto; Joop Schaye; Volker Springel; Lars Hernquist

2004-09-29T23:59:59.000Z

222

Magnetic nanotubes  

DOE Patents (OSTI)

A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

2010-11-16T23:59:59.000Z

223

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

Mit Hilfe der Technologie supraleitender Magnete lassen sich in Mit Hilfe der Technologie supraleitender Magnete lassen sich in Ringbeschleunigern höhere Energien erreichen. Weil supraleitende Spulen keinen elektrischen Widerstand aufweisen, können damit stärkere Magnetfelder erzeugt werden. In normal leitenden Elektromagneten wird - wegen des elektrischen Widerstands der Drähte - die Spule aufgeheizt. Auf diese Weise geht sehr viel Energie in Form von Wärme verloren, was die Energiekosten dieser Magnete in die Höhe treibt. Supraleitende Spulen erlauben es, Magnete grosser Feldstärke unter günstigen Bedingungen zu betreiben und damit die Energiekosten zu senken. Durch den Einbau supraleitender Spulen in den Ringbeschleuniger von Fermilab konnte dessen Energie verdoppelt werden.Auch der im Bau befindliche "Large Hadron Collider" am CERN wird supraleitende Magnete

224

Fan-less long range alpha detector  

DOE Patents (OSTI)

A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

MacArthur, Duncan W. (Los Alamos, NM); Bounds, John A. (Los Alamos, NM)

1994-01-01T23:59:59.000Z

225

Fan-less long range alpha detector  

DOE Patents (OSTI)

A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

MacArthur, D.W.; Bounds, J.A.

1994-05-10T23:59:59.000Z

226

FTIR spectrometer with solid-state drive system  

DOE Patents (OSTI)

An FTIR spectrometer (10) and method using a solid-state drive system with thermally responsive members (27) that are subject to expansion upon heating and to contraction upon cooling. Such members (27) are assembled in the device (10) so as to move an angled, reflective surface (22) a small distance. The sample light beam (13) is received at a detector (24) along with a reference light beam (13) and there it is combined into a resulting signal. This allows the "interference" between the two beams to occur for spectral analysis by a processor (29).

Rajic, Slobodan (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Egert, Charles M. (Oak Ridge, TN)

1999-01-01T23:59:59.000Z

227

Bent solenoids for spectrometers and emittance exchange sections.  

Science Conference Proceedings (OSTI)

Bent solenoids can be used to transport low energy beams as they provide both confinement and dispersion of particle orbits. Solenoids are being considered both as emittance exchange sections and spectrometers in the muon cooling system as part of the study of the muon collider. They present the results of a study of bent solenoids which considers the design of coupling sections between bent solenoids to straight solenoids, drift compensation fields, aberrations, and factors relating to the construction, such as field ripple, stored energy, coil forces and field errors.

Norem, J.

1999-03-26T23:59:59.000Z

228

Light Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory  

Science Conference Proceedings (OSTI)

Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom underlying nucleon matter. High-energy electrons and photons are a remarkably clean probe of hadronic matter, providing a microscope for examining the nucleon and the strong nuclear force. Current experimental efforts with the CLAS spectrometer at Jefferson Laboratory utilize highly-polarized frozen-spin targets in combination with polarized photon beams. The status of the recent double-polarization experiments and some preliminary results are discussed in this contribution.

Volker Crede

2011-12-01T23:59:59.000Z

229

Chemical detection using the airborne thermal infrared imaging spectrometer (TIRIS)  

SciTech Connect

A methodology is described for an airborne, downlooking, longwave infrared imaging spectrometer based technique for the detection and tracking of plumes of toxic gases. Plumes can be observed in emission or absorption, depending on the thermal contrast between the vapor and the background terrain. While the sensor is currently undergoing laboratory calibration and characterization, a radiative exchange phenomenology model has been developed to predict sensor response and to facilitate the sensor design. An inverse problem model has also been developed to obtain plume parameters based on sensor measurements. These models, the sensors, and ongoing activities are described.

Gat, N.; Subramanian, S.; Sheffield, M.; Erives, H. [Opto-Knowledge Systems, Inc. (United States); Barhen, J. [Oak Ridge National Lab., TN (United States)

1997-04-01T23:59:59.000Z

230

Test of an LED Monitoring System for the PHOS Spectrometer  

E-Print Network (OSTI)

Preprint submitted to Elsevier Print on 26th January 2000A prototype monitoring system for the Photon Spectrometer (PHOS) of the ALICE experiment at LHC is described in detail. The prototype consists of Control and Master modules. The first one is 8x8 matrix of Light Emitting Diodes coupled with stable generators of current pulses. The system provides an individual control for each of the 64 channels of PHOS prototype based on lead-tungstate crystals. A long term stability of order of 10-3 has been achieved in integral beam tests of the monitoring system and PHOS prototypes.

Blick, A M; Erin, S V; Kharlov, Yu V; Lobanov, M O; Mikhailov, Yu V; Minaev, N G; Petrov, V A; Sadovsky, S A; Samoylenko, V D; Suzdalev, V I; Senko, V A; Tikhonov, V V

1999-01-01T23:59:59.000Z

231

Stochastic Heating, Differential Flow, and the Alpha-to-Proton Temperature Ratio in the Solar Wind  

E-Print Network (OSTI)

We extend previous theories of stochastic ion heating to account for the motion of ions along the magnetic field. We derive an analytic expression for the ion-to-proton perpendicular temperature ratio in the solar wind for any ion species, assuming that stochastic heating is the dominant ion heating mechanism. This expression describes how this temperature ratio depends upon the average velocity of the ions along the magnetic field direction and the ratio of the parallel proton pressure to the magnetic pressure. We compare our model with previously published measurements of alpha particles and protons from the WIND spacecraft. We find that stochastic heating offers a promising explanation for these measurements when the fractional cross helicity and Alfven ratio at the proton-gyroradius scale have values that are broadly consistent with solar-wind measurements.

Chandran, B D G; Quataert, E; Kasper, J C; Isenberg, P A; Bourouaine, S

2013-01-01T23:59:59.000Z

232

Design of the superconducting 45 degree dipole for the CEBAF high resolution spectrometers  

Science Conference Proceedings (OSTI)

The 460-ton dipole for the Hall A 4-GeV/c High Resolution Spectrometer has a bend angle of 45{sup o}, with an 8.4-m radius of curvature and an effective length of 6.6 m. It has a useful width of 100 cm and a 25-cm gap at the central radius of curvature. The dipole provides focusing in the dispersive plane by means of rotated (by 30 degrees) entrance and exit pole faces as well as a field index of -1.25. The end contour geometries have been designed to eliminate higher-order aberrations. The maximum central field is 1.6 T at 4 GeV/c. A field quality of 2 x 10{sup -4} (maximum deviation from the design value) is required over an excitation range from 0.16 T to 1.6 T. The 1.8-kA conductor is a 36-wire flattened cable. It has been designed to have limited cryostability at 4.5 K and 1.3 atm. Each coil is wound as one double pancake against the outer wall of the helium vessel in order to react the in-plane (hoop) loads. The bath-cooled, planar coil features negative curvature on its inner radius and at the exit. The coil produces 400 KAT at full excitation. The stored energy of this magnet is 3.5 MJ.

Alan Gavalya; John Alcorn; Walter Tuzel

1990-09-24T23:59:59.000Z

233

Transformer Recharging with Alpha Channeling in Tokamaks  

SciTech Connect

Transformer recharging with lower hybrid waves in tokamaks can give low average auxiliary power if the resistivity is kept high enough during the radio frequency (rf) recharging stage. At the same time, operation in the hot ion mode via alpha channeling increases the effective fusion reactivity. This paper will address the extent to which these two large cost saving steps are compatible. __________________________________________________

N.J. Fisch

2009-12-21T23:59:59.000Z

234

Temperature Sensitivity of Lyman-Alpha Hygrometers  

Science Conference Proceedings (OSTI)

The response of an E.R.C. Lyman-alpha hygrometer to humidity and temperature variations has been experimentally determined in a humidity calibration tunnel. The data are compared to a simple two-gas/two-line model to determine the errors made in ...

P. Mestayer; C. Rebattet

1985-12-01T23:59:59.000Z

235

Optical apparatus for forming correlation spectrometers and optical processors  

DOE Patents (OSTI)

Optical apparatus is disclosed for forming correlation spectrometers and optical processors. The optical apparatus comprises one or more diffractive optical elements formed on a substrate for receiving light from a source and processing the incident light. The optical apparatus includes an addressing element for alternately addressing each diffractive optical element thereof to produce for one unit of time a first correlation with the incident light, and to produce for a different unit of time a second correlation with the incident light that is different from the first correlation. In preferred embodiments of the invention, the optical apparatus is in the form of a correlation spectrometer; and in other embodiments, the apparatus is in the form of an optical processor. In some embodiments, the optical apparatus comprises a plurality of diffractive optical elements on a common substrate for forming first and second gratings that alternately intercept the incident light for different units of time. In other embodiments, the optical apparatus includes an electrically-programmable diffraction grating that may be alternately switched between a plurality of grating states thereof for processing the incident light. The optical apparatus may be formed, at least in part, by a micromachining process. 24 figs.

Butler, M.A.; Ricco, A.J.; Sinclair, M.B.; Senturia, S.D.

1999-05-18T23:59:59.000Z

236

The measurement of $\\alpha_s$ from event shapes with the DELPHI detector at the highest LEP energies  

E-Print Network (OSTI)

Hadronic event shape distributions are determined from data in e+e- collisions between 183 and 207 GeV. From these the strong coupling alpha_s is extracted in O(alpha_s^2), NLLA and matched O(alpha_s^2)+NLLA theory. Hadronisation corrections evaluated with fragmentation model generators as well as an analytical power ansatz are applied. Comparing these measurements to those obtained at and around M_Z allows a combined measurement of alpha_s from all DELPHI data and a test of the energy dependence of the strong coupling.

Abdallah, J; Adam, W; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Ben-Haim, E; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bloch, D; Blom, M; Bluj, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Brenner, R; Brodet, E; Brückman, P; Brunet, J M; Bugge, L; Buschmann, P; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F R; Chapkin, M M; Charpentier, P; Checchia, P; Chierici, R; Shlyapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Crennell, D J; Cuevas-Maestro, J; D'Hondt, J; Dalmau, J; Da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L S; Di Ciaccio, Lucia; Di Simone, A; Doroba, K; Drees, J; Dris, M; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Föth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J A; Gandelman, M; García, C; Gavillet, P; Gazis, E N; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Herr, H; Hoffman, J; Holmgren, S O; Holt, P J; Houlden, M A; Hultqvist, K; Jackson, J N; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Katsanevas, S; Katsoufis, E C; Kernel, G; Kersevan, Borut P; Kerzel, U; Kiiskinen, A P; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kuznetsov, O; Krumshtein, Z; Kucharczyk, M; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Mönig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Müller, U; Münich, K; Mulders, M; Mundim, L M; Murray, W; Muryn, B; Myatt, Gerald; Myklebust, T; Nassiakou, M; Navarria, Francesco Luigi; Nawrocki, K; Nicolaidou, R; Nikolenko, M; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Pukhaeva, N; Pullia, Antonio; Rames, J; Ramler, L; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rídky, J; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovskii, A; Salmi, L; Salt, J; Savoy-Navarro, A; Schwickerath, U; Segar, A; Sekulin, R L; Siebel, M; Sissakian, A N; Smadja, G; Smirnova, O G; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tkatchev, L G; Tobin, M; Todorovova, S; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tzamarias, S; Uvarov, V; Valenti, G; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Remortel, N; Van Vulpen, I B; Vegni, G; Veloso, F; Venus, W A; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zhuravlov, V; Zimin, N I; Zinchenko, A I; Zupan, M

2004-01-01T23:59:59.000Z

237

Comparison between Standard and Modified Forward Scattering Spectrometer Probes during the Small Cumulus Microphysics Study  

Science Conference Proceedings (OSTI)

Microphysical measurements performed during the Small Cumulus Microphysics Study (SCMS) experiment are analyzed in order to examine the instrumental limitations of forward scattering spectrometer probes (FSSPs). Complementary information ...

Frédéric Burnet; Jean-Louis Brenguier

2002-10-01T23:59:59.000Z

238

A time-of-flight backscattering spectrometer at the Spallation Neutron Source, BASIS  

Science Conference Proceedings (OSTI)

We describe the design and current performance of the backscattering silicon spectrometer (BASIS), a time-of-flight backscattering spectrometer built at the spallation neutron source (SNS) of the Oak Ridge National Laboratory (ORNL). BASIS is the first silicon-based backscattering spectrometer installed at a spallation neutron source. In addition to high intensity, it offers a high-energy resolution of about 3.5 {mu}eV and a large and variable energy transfer range. These ensure an excellent overlap with the dynamic ranges accessible at other inelastic spectrometers at the SNS.

Mamontov, E.; Herwig, K. W. [Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2011-08-15T23:59:59.000Z

239

Learning About Magnets!  

NLE Websites -- All DOE Office Websites (Extended Search)

the the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force that can "attract" or "repel" other magnets and magnetic materials, like iron or nickel. What is a Magnet? This bar magnet is a permanent magnet. Permanent magnets can be found in the Earth as rocks and metals. Magnets have

240

Experimental investigations of electron capture from atomic hydrogen and deuterium by alpha particles  

DOE Green Energy (OSTI)

We have undertaken a program at the University of Missouri-Rolla to experimentally determine cross sections for ion-atom collisions of interest in fusion reactor development. During the last grant period, we finished measurements of total sections for the alpha single-capture reaction (1) He{sup ++} + He(1s{sup 2}) {yields} He{sup +}(n) + He{sup +}(1s), and we propose to study (2) He{sup ++} + H(1s) {yields} He{sup +}(n) + H{sup +} this year. Accurate knowledge of these cross sections is fundamental for modeling of neutral-hydrogen beam penetration in fusion plasmas as well as for spectroscopic diagnostics of alpha densities and velocity distributions, especially for the case of capture into the n=4 state of the projectile He{sup +}. Our measurements are made using a unique collision spectrometer discussed below. Reaction (1) was studied for alpha energies between 45 and 135 keV, using the technique of ion-energy spectroscopy. This technique has two major advantages over optical measurements. First, cascading corrections are avoided because the fast collision partner is detected, rather than a secondary photon. Second, no knowledge of detector efficiencies is required, because a ratio of the scattered to incident beam counting rates is measured. Two sources of possible systematic error in the determination of final cross sections are thereby eliminated. Moreover, we have studied the angular dependence of cross sections for (1), and can thus be certain that the measured total cross sections are not low due to incomplete angular acceptance of the apparatus, a problem known to exist in some previous total cross section measurements of this type.

Not Available

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Study of alpha background in a dark matter detector  

E-Print Network (OSTI)

Alpha background, specifically from radon and its progeny in the uranium and thorium chains, has been a major issue in dark matter detectors. This work focuses on alpha background presence in the DMTPC experiment by examining ...

Yegoryan, Hayk

2010-01-01T23:59:59.000Z

242

Antibody-mediated reduction of .alpha.-ketoamides  

DOE Patents (OSTI)

Monoclonal antibodies raised against a 4-nitrophenyl phosphonate hapten catalyze the stereospecific reduction of an .alpha.-ketoamide to the corresponding .alpha.-hydroxyamide in the presence of an appropriate reducing agent.

Schultz, Peter G. (Oakland, CA); Gallop, Mark A. (East Palo Alto, CA)

1998-01-01T23:59:59.000Z

243

Antibody-mediated reduction of {alpha}-ketoamides  

DOE Patents (OSTI)

Monoclonal antibodies raised against a 4-nitrophenyl phosphonate hapten catalyze the stereospecific reduction of an {alpha}-ketoamide to the corresponding {alpha}-hydroxyamide in the presence of an appropriate reducing agent.

Schultz, P.G.; Gallop, M.A.

1998-06-09T23:59:59.000Z

244

Preliminary Test Results for the MICE Spectrometer Superconducting Solenoids  

E-Print Network (OSTI)

the pipes connecting the condensers to the cold mass wereand the pipes that connect the condenser to the magnet.The pipes connecting the condenser to the cold mass can also

Virostek, Steve P.

2009-01-01T23:59:59.000Z

245

Neutrino magnetic moment in a magnetized plasma  

E-Print Network (OSTI)

The contribution of a magnetized plasma to the neutrino magnetic moment is calculated. It is shown that only part of the additional neutrino energy in magnetized plasma connecting with its spin and magnetic field strength defines the neutrino magnetic moment. It is found that the presence of magnetized plasma does not lead to the considerable increase of the neutrino magnetic moment in contrast to the results presented in literature previously.

N. V. Mikheev; E. N. Narynskaya

2010-11-08T23:59:59.000Z

246

Some numerical reslts on best uniform polynomial approximation of. chi. sup. alpha. on (0,1)  

SciTech Connect

Let {alpha} be a positive number, and let E{sub n}(chi{sup {alpha}}; (0,1)) denote the error of best uniform approximation to {chi}{sup {alpha}}, by polynomials of degree at most n, on the interval (0,1). The Russian mathematician S.N. Bernstein established the existence of a nonnegative constant {Beta}({alpha}) such that {Beta}({alpha}):= {sub n{yields}{infinity}lim(2n){sup 2{alpha}}E{sub n}({chi}{sup {alpha}};(0.1)). In addition, Bernstein showed that {Beta}{alpha} < {Gamma}(2{alpha}){vert bar}sin(pi}{alpha}){vert bar}/{pi} ({alpha} > 0) and that {Gamma}(2{alpha}){vert bar}sin({pi}{alpha}){vert bar}/{pi} (1{minus}1/2{alpha}{minus}1) < {Beta}({alpha}) ({alpha} > {1/2}), so that the asymptotic behavior of {Beta}({alpha}) is known when {alpha}{yields}{infinity}. Still, the problem of trying to determine {Beta}({alpha}) more precisely, for all {alpha} > 0, is intriguing. To this end, we have rigorously determined the numbers for thirteen values of {alpha}, where these numbers were calculated with a precision of at least 200 significant digits. For each of these thirteen values of {alpha}, Richardson's extrapolation was applied to the products to obtain estimates of {Beta}({alpha}) to approximately 40 decimal places. Included are graphs of the points ({alpha},{Beta}({alpha})) for the thirteen values of {alpha} that we considered.

Carpenter, A.J.; Varga, R.S.

1992-01-01T23:59:59.000Z

247

Passive Millimeter-Wave Spectrometer for Remote Chemical Detection  

NLE Websites -- All DOE Office Websites (Extended Search)

Closed Captioning Transcript Closed Captioning Transcript Welcome to a demonstration of the Passive Millimeter-Wave Spectrometer for Remote Chemical Detection. The ultimate goal of the project was to detect a hot target gas in front of a cooler background. This setup was eventually tested at the Nevada Test Site. Prior to field test we tested the concept in a laboratory. We simulated the field conditions by simultaneously reducing the two relative temperatures. In this demonstration we will show a room temperature gas (CH3CN) with a cold background (liquid nitrogen). To understand the experiment we will be showing, the first subplot here represents all data channels plotted on a single plot, the second plot represents a two-dimensional representation of the same data, the X axis represents time, the Y axis represents frequency. As the plot is animated later the first and second subplots will have a cross section marker sweep across them.

248

Aerosol beam-focus laser-induced plasma spectrometer device  

SciTech Connect

An apparatus for detecting elements in an aerosol includes an aerosol beam focuser for concentrating aerosol into an aerosol beam; a laser for directing a laser beam into the aerosol beam to form a plasma; a detection device that detects a wavelength of a light emission caused by the formation of the plasma. The detection device can be a spectrometer having at least one grating and a gated intensified charge-coupled device. The apparatus may also include a processor that correlates the wavelength of the light emission caused by the formation of the plasma with an identity of an element that corresponds to the wavelength. Furthermore, the apparatus can also include an aerosol generator for forming an aerosol beam from bulk materials. A method for detecting elements in an aerosol is also disclosed.

Cheng, Meng-Dawn (Oak Ridge, TN)

2002-01-01T23:59:59.000Z

249

Linear electronic field time-of-flight ion mass spectrometers  

DOE Patents (OSTI)

Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber; a means of introducing an analyte of interest into the first drift region; a pulsed ionization source which produces molecular ions from said analyte of interest; a first foil positioned between the first drift region and the second drift region, which dissociates said molecular ions into constituent atomic ions and emits secondary electrons; an electrode which produces secondary electrons upon contact with a constituent atomic ion in second drift region; a stop detector comprising a first ion detection region and a second ion detection region; and a timing means connected to the pulsed ionization source, to the first ion detection region, and to the second ion detection region.

Funsten, Herbert O. (Los Alamos, NM)

2010-08-24T23:59:59.000Z

250

Neutron beam imaging at neutron spectrometers at Dhruva  

SciTech Connect

A low efficiency, 2-Dimensional Position Sensitive Neutron Detector based on delay line position encoding is developed. It is designed to handle beam flux of 10{sup 6}-10{sup 7} n/cm{sup 2}/s and for monitoring intensity profiles of neutron beams. The present detector can be mounted in transmission mode, as the hardware allows maximum neutron transmission in sensitive region. Position resolution of 1.2 mm in X and Y directions, is obtained. Online monitoring of beam images and intensity profile of various neutron scattering spectrometers at Dhruva are presented. It shows better dynamic range of intensity over commercial neutron camera and is also time effective over the traditionally used photographic method.

Desai, Shraddha S.; Rao, Mala N. [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

2012-06-05T23:59:59.000Z

251

Report on Second Activations with the Lead Slowing Down Spectrometer  

SciTech Connect

Summary On August 18 and 19 2011, five items were irradiated with neutrons using the Lead Slowing Down Spectrometer (LSDS). After irradiation, dose measurements and gamma-spectrometry measurements were completed on all of the samples. No contamination was found on the samples, and all but one provided no dose. Gamma-spectroscopy measurements qualitatively agreed with expectations based on the materials. As during the first activation run, we observed activation in the room in general, mostly due to 56Mn and 24Na. Most of the activation of the samples was short lived, with half-lives on the scale of hours to days, except for 60Co which has a half-life of 5.3 y.

Stave, Sean C.; Mace, Emily K.; Pratt, Sharon L.; Warren, Glen A.

2012-04-27T23:59:59.000Z

252

Imaging X-ray Thomson Scattering Spectrometer Design and Demonstration  

SciTech Connect

In many laboratory astrophysics experiments, intense laser irradiation creates novel material conditions with large, one-dimensional gradients in the temperature, density, and ionization state. X-ray Thomson scattering is a powerful technique for measuring these plasma parameters. However, the scattered signal has previously been measured with little or no spatial resolution, which limits the ability to diagnose inhomogeneous plasmas. We report on the development of a new imaging x-ray Thomson spectrometer (IXTS) for the Omega laser facility. The diffraction of x-rays from a toroidally-curved crystal creates high-resolution images that are spatially resolved along a one-dimensional profile while spectrally dispersing the radiation. This focusing geometry allows for high brightness while localizing noise sources and improving the linearity of the dispersion. Preliminary results are presented from a scattering experiment that used the IXTS to measure the temperature profile of a shocked carbon foam.

Gamboa, E.J. [University of Michigan; Huntington, C.M. [University of Michigan; Trantham, M.R. [University of Michigan; Keiter, P.A [University of Michigan; Drake, R.P. [University of Michigan; Montgomery, David [Los Alamos National Laboratory; Benage, John F. [Los Alamos National Laboratory; Letzring, Samuel A. [Los Alamos National Laboratory

2012-05-04T23:59:59.000Z

253

Dynamic multiplexed analysis method using ion mobility spectrometer  

DOE Patents (OSTI)

A method for multiplexed analysis using ion mobility spectrometer in which the effectiveness and efficiency of the multiplexed method is optimized by automatically adjusting rates of passage of analyte materials through an IMS drift tube during operation of the system. This automatic adjustment is performed by the IMS instrument itself after determining the appropriate levels of adjustment according to the method of the present invention. In one example, the adjustment of the rates of passage for these materials is determined by quantifying the total number of analyte molecules delivered to the ion trap in a preselected period of time, comparing this number to the charge capacity of the ion trap, selecting a gate opening sequence; and implementing the selected gate opening sequence to obtain a preselected rate of analytes within said IMS drift tube.

Belov, Mikhail E [Richland, WA

2010-05-18T23:59:59.000Z

254

Ion mobility spectrometer using frequency-domain separation  

DOE Patents (OSTI)

An apparatus and method are provided for separating and analyzing chemical species in an ion mobility spectrometer using a frequency-domain technique wherein the ions generated from the chemical species are selectively transported through an ion flow channel having a moving electrical potential therein. The moving electrical potential allows the ions to be selected according to ion mobility, with certain of the ions being transported to an ion detector and other of the ions being effectively discriminated against. The apparatus and method have applications for sensitive chemical detection and analysis for monitoring of exhaust gases, hazardous waste sites, industrial processes, aerospace systems, non-proliferation, and treaty verification. The apparatus can be formed as a microelectromechanical device (i.e. a micromachine). 6 figs.

Martin, S.J.; Butler, M.A.; Frye, G.C.; Schubert, W.K.

1998-08-04T23:59:59.000Z

255

Ion mobility spectrometer using frequency-domain separation  

DOE Patents (OSTI)

An apparatus and method is provided for separating and analyzing chemical species in an ion mobility spectrometer using a frequency-domain technique wherein the ions generated from the chemical species are selectively transported through an ion flow channel having a moving electrical potential therein. The moving electrical potential allows the ions to be selected according to ion mobility, with certain of the ions being transported to an ion detector and other of the ions being effectively discriminated against. The apparatus and method have applications for sensitive chemical detection and analysis for monitoring of exhaust gases, hazardous waste sites, industrial processes, aerospace systems, non-proliferation, and treaty verification. The apparatus can be formed as a microelectromechanical device (i.e. a micromachine).

Martin, Stephen J. (Albuquerque, NM); Butler, Michael A. (Albuquerque, NM); Frye, Gregory C. (Cedar Crest, NM); Schubert, W. Kent (Albuquerque, NM)

1998-01-01T23:59:59.000Z

256

Automatically processed alpha-track radon monitor  

DOE Patents (OSTI)

An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

Langner, G.H. Jr.

1991-05-02T23:59:59.000Z

257

Alternate Alpha Induced Reactions for NIF Radiochemistry  

SciTech Connect

Radiochemical analysis of NIF capsule residues has been identified as a potential diagnostic of NIF capsule performance. In particular, alpha-induced nuclear reactions that occur on tracer elements added to the NIF capsule have been shown through simulation to be a very sensitive diagnostic for mix. The short range of the alpha particles makes them representative of the hot spot where they are created through the fusion of deuterium and tritium. Reactions on elements doped into the innermost part of the capsule ablator would therefore be sensitive to material that had mixed into the hot spot. Radiochemical determinations of activated detector elements may perhaps be the only true measure of mix that occurs in a NIF capsule, particularly in cases when the capsule fails.

Shaughnessy, D A; Moody, K J; Bernstein, L A

2010-02-26T23:59:59.000Z

258

Calibration of the Spectrometer aboard the INTEGRAL satellite  

E-Print Network (OSTI)

SPI, the Spectrometer on board the ESA INTEGRAL satellite, to be launched in October 2002, will study the gamma-ray sky in the 20 keV to 8 MeV energy band with a spectral resolution of 2 keV for photons of 1 MeV, thanks to its 19 germanium detectors spanning an active area of 500 cm2. A coded mask imaging technique provides a 2 deg angular resolution. The 16 deg field of view is defined by an active BGO veto shield, furthermore used for background rejection. In April 2001 the flight model of SPI underwent a one-month calibration campaign at CEA in Bruy\\`eres le Ch\\^atel using low intensity radioactive sources and the CEA accelerator for homogeneity measurements and high intensity radioactive sources for imaging performance measurements. After integration of all scientific payloads (the spectrometer SPI, the imager IBIS and the monitors JEM-X and OMC) on the INTEGRAL satellite, a cross-calibration campaign has been performed at the ESA center in Noordwijk. A set of sources has been placed in the field of view of the different instruments in order to compare their performances and determine their mutual influence. Some of those sources had already been used in Bruy\\`eres during the SPI standalone test. For the lowest energy band calibration an X-ray generator has been used. We report on the scientific goals of this calibration activity, and present the measurements performed as well as some preliminary results.

Stéphane Schanne; B. Cordier; M. Gros; D. Attié; P. v. Ballmoos; L. Bouchet; R. Carli; P. Connell; R. Diehl; P. Jean; J. Kiener; A. v. Kienlin; J. Knödlseder; P. Laurent; G. Lichti; P. Mandrou; J. Paul; P. Paul; J. -P. Roques; F. Sanchez; V. Schönfelder; C. Shrader; G. Skinner; A. Strong; S. Sturner; V. Tatischeff; B. Teegarden; G. Vedrenne; G. Weidenspointner; C. Wunderer

2003-10-28T23:59:59.000Z

259

Magnetization Characterization Laboratory  

Science Conference Proceedings (OSTI)

... use of magnetic materials for motors, generators, transformers ... all depend on the specific magnetic characteristics of ... For example, a magnet used in ...

2012-10-23T23:59:59.000Z

260

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network (OSTI)

Scale Superconducting Magnetic Energy Storage Plant", IEEEfor SlIperconducting Magnetic Energy Storage Unit", inSuperconducting Magnetic Energy Storage Plant, Advances in

Hassenzahl, W.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

MAGNETIC GRID  

DOE Patents (OSTI)

An electronic grid is designed employing magnetic forces for controlling the passage of charged particles. The grid is particularly applicable to use in gas-filled tubes such as ignitrons. thyratrons, etc., since the magnetic grid action is impartial to the polarity of the charged particles and, accordingly. the sheath effects encountered with electrostatic grids are not present. The grid comprises a conductor having sections spaced apart and extending in substantially opposite directions in the same plane, the ends of the conductor being adapted for connection to a current source.

Post, R.F.

1960-08-01T23:59:59.000Z

262

Application in the Ethanol Fermentation of Immobilized Yeast Cells in Matrix of Alginate/Magnetic Nanoparticles, on Chitosan-Magnetite Microparticles and Cellulose-coated Magnetic Nanoparticles  

E-Print Network (OSTI)

Saccharomyces cerevisiae cells were entrapped in matrix of alginate and magnetic nanoparticles and covalently immobilized on magnetite-containing chitosan and cellulose-coated magnetic nanoparticles. Cellulose-coated magnetic nanoparticles with covalently immobilized thermostable {\\alpha}-amylase and chitosan particles with immobilized glucoamylase were also prepared. The immobilized cells and enzymes were applied in column reactors - 1/for simultaneous corn starch saccharification with the immobilized glucoamylase and production of ethanol with the entrapped or covalently immobilized yeast cells, 2/ for separate ethanol fermentation of the starch hydrolysates with the fixed yeasts. Hydrolysis of corn starch with the immobilized {\\alpha}-amylase and glucoamylase, and separate hydrolysis with the immobilized {\\alpha}-amylase were also examined. In the first reactor the ethanol yield reached approx. 91% of the theoretical; the yield was approx. 86% in the second. The ethanol fermentation was affected by the typ...

Ivanova, Viara; Hristov, Jordan

2011-01-01T23:59:59.000Z

263

The Acceleration of Ions in Solar Flares During Magnetic Reconnection  

E-Print Network (OSTI)

The acceleration of solar flare ions during magnetic reconnection is explored via particle-in-cell simulations that self-consistently follow the motions of both protons and $\\alpha$ particles. We demonstrate that the dominant ion heating during reconnection with a guide field (a magnetic component perpendicular to the reconnection plane) results from pickup behavior during the entry into reconnection exhausts. In contrast with anti-parallel reconnection, the temperature increment is dominantly transverse, rather than parallel, to the local magnetic field. The comparison of protons and alphas reveals a mass-to-charge ($M/Q$) threshold in pickup behavior that favors heating of high $M/Q$ ions over protons, which is consistent with impulsive flare observations.

Knizhnik, Kalman; Drake, James F

2011-01-01T23:59:59.000Z

264

An Intercomparison of Two Tunable Diode Laser Spectrometers Used for Eddy Correlation Measurements of Methane Flux in a Prairie Wetland  

Science Conference Proceedings (OSTI)

An intercomparison was made between two tunable diode laser spectrometers used to measure methane fluxes by the eddy correlation technique at a prairie wetland site. The spectrometers were built by Unisearch Associates Inc. of Concord, Ontario, ...

D. P. Billesbach; Joon Kim; R. J. Clement; S. B. Verma; F. G. Ullman

1998-02-01T23:59:59.000Z

265

Questions about Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

off just the north (or just the south) end of a magnet? Are magnets stronger than gravity? Hold a magnet in the air. Place a nail against it. The magnet holds the nail up...

266

Intensity-Frontier Antiproton Physics with The Antiproton Annihilation Spectrometer (TAPAS) at Fermilab  

SciTech Connect

The Fermilab Antiproton Source is the world's most intense source of antimatter. With the Tevatron program now behind us, this unique facility can help make the case for Fermilab's continued accelerator operations. The Antiproton Source can be used for unique, dedicated antimatter studies, including medium-energy {bar p}-annihilation experiments. We propose to assemble a powerful, yet cost-effective, solenoidal magnetic spectrometer for antiproton-annihilation events, and to use it at the Fermilab Antiproton Accumulator to measure the charm production cross section, study rare hyperon decays, search for hyperon CP asymmetry, precisely measure the properties of several charmonium and nearby states, and make the first measurements of the Drell-Yan continuum in medium-energy antiproton annihilation. Should the charm production cross section be as large as some have proposed, we will also be able to measure D{sup 0}-{bar D}{sup 0} mixing with high precision and discover (or sensitively limit) charm CP violation. The observation of charm or hyperon CP violation would be evidence for physics beyond the Standard Model, with possible implications for the origin of the baryon asymmetry of the universe - the question of what happened to all the antimatter that must have been produced in the Big Bang. The experiment will be carried out by an international collaboration and will require some four years of running time. As possibly the sole hadron experiment in progress at Fermilab during that time, it will play an important role in maintaining a broad particle physics program at Fermilab and in the U.S. It will thus help us to continue attracting creative and capable young people into science and technology, and introducing them to the important technologies of accelerators, detectors, and data acquisition and analysis - key roles in society that accelerator-based particle physics has historically played.

Apollinari, Giorgio; /Fermilab; Asner, David M.; /PNL, Richland; Baldini, Wander; /INFN, Ferrara; Bartoszek, Larry; Broemmelsiek, Daniel R.; Brown, Charles N.; /Fermilab; Chakravorty, Alak; /St. Xavier U., Chicago; Colas, Paul; /Saclay; Derwent, Paul; /Fermilab; Drutskoy, Alexey; /Moscow, ITEP; Fortner, Michael; /Northern Illinois U. /Saclay /Indian Inst. Tech., Hyderabad

2011-11-01T23:59:59.000Z

267

FLUX EMERGENCE IN A MAGNETIZED CONVECTION ZONE  

Science Conference Proceedings (OSTI)

We study the influence of a dynamo magnetic field on the buoyant rise and emergence of twisted magnetic flux ropes and their influence on the global external magnetic field. We ran three-dimensional MHD numerical simulations using the ASH code (anelastic spherical harmonics) and analyzed the dynamical evolution of such buoyant flux ropes from the bottom of the convection zone until the post-emergence phases. The global nature of this model can only very crudely and inaccurately represent the local dynamics of the buoyant rise of the implanted magnetic structure, but nonetheless allows us to study the influence of global effects, such as self-consistently generated differential rotation and meridional circulation, and of Coriolis forces. Although motivated by the solar context, this model cannot be thought of as a realistic model of the rise of magnetic structures and their emergence in the Sun, where the local dynamics are completely different. The properties of initial phases of the buoyant rise are determined essentially by the flux-rope's properties and the convective flows and consequently are in good agreement with previous studies. However, the effects of the interaction of the background dynamo field become increasingly strong as the flux ropes evolve. During the buoyant rise across the convection zone, the flux-rope's magnetic field strength scales as B{proportional_to}{rho}{sup {alpha}}, with {alpha} {approx}current density is observed to precede flux emergence at all longitudes. The geometry, latitude, and relative orientation of the flux ropes with respect to the background magnetic field influences the resulting rise speeds, zonal flow amplitudes (which develop within the flux ropes), and the corresponding surface signatures. This influences the morphology, duration and amplitude of the surface shearing, and the Poynting flux associated with magnetic flux-rope emergence. The emerged magnetic flux influences the system's global polarity, leading in some cases to a polarity reversal while inhibiting the background dynamo from doing so in others. The emerged magnetic flux is slowly advected poleward while being diffused and assimilated by the background dynamo field.

Pinto, R. F.; Brun, A. S., E-mail: rui.pinto@cea.fr [Laboratoire AIM Paris-Saclay, CEA/Irfu Universite Paris-Diderot CNRS/INSU, F-91191 Gif-sur-Yvette (France)

2013-07-20T23:59:59.000Z

268

magnets2  

NLE Websites -- All DOE Office Websites (Extended Search)

II II Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

269

In-situ droplet monitoring for self-tuning spectrometers  

DOE Patents (OSTI)

A laser scattering based imaging technique is utilized in order to visualize the aerosol droplets in an inductively coupled plasma (ICP) torch from an aerosol source to the site of analytical measurements. The resulting snapshots provide key information about the spatial distribution of the aerosol introduced by direct and indirect injection devices: 1) a direct injection high efficiency nebulizer (DIHEN); 2) a large-bore DIHEN (LB-DIHEN); and 3) a PFA microflow nebulizer with a PFA Scott-type spray chamber. Moreover, particle image velocimetry (PIV) is used to study the in-situ behavior of the aerosol before interaction with, for example, plasma, while the individual surviving droplets are explored by particle tracking velocimetry (PTV). Further, the velocity distribution of the surviving droplets demonstrates the importance of the initial droplet velocities in complete desolvation of the aerosol for optimum analytical performance in ICP spectrometries. These new observations are important in the design of the next-generation direct injection devices for lower sample consumption, higher sensitivity, lower noise levels, suppressed matrix effects, and for developing smart spectrometers. For example, a controller can be provided to control the output of the aerosol source by controlling the configuration of the source or the gas flow rate via feedback information concerning the aerosol.

Montaser, Akbar (Potomac, MD); Jorabchi, Kaveh (Arlington, VA); Kahen, Kaveh (Kleinburg, CA)

2010-09-28T23:59:59.000Z

270

Magnetic Charge of the Stark States of Hydrogen Atoms  

E-Print Network (OSTI)

It is conjectured that Stark states of excited hydrogen atom posses magnetic charge for which the quantum mechanical operator is $${\\cal G}_{op} = {e\\over \\hbar} (\\vec\\sigma\\cdot\\vec A)$$ where $\\vec A$ is the Runge-Lenz vector. The expectation value $g$ of this operator for Stark states is found to be $$ g = e(n_1-n_2)$$ which obeys a Dirac-Saha type quantization formula $${eg\\over c} = (n_1-n_2)\\alpha$$ where $\\alpha$ is the fine structure constant and $n_1$ and $n_2$ are parabolic quantum numbers. An experimental arrangement is outlined to test this conjecture.

T. Pradhan

2008-09-28T23:59:59.000Z

271

Magnetic Reconnection  

SciTech Connect

We review the fundamental physics of magnetic reconnection in laboratory and space plasmas, by discussing results from theory, numerical simulations, observations from space satellites, and the recent results from laboratory plasma experiments. After a brief review of the well-known early work, we discuss representative recent experimental and theoretical work and attempt to interpret the essence of significant modern findings. In the area of local reconnection physics, many significant findings have been made with regard to two- uid physics and are related to the cause of fast reconnection. Profiles of the neutral sheet, Hall currents, and the effects of guide field, collisions, and micro-turbulence are discussed to understand the fundamental processes in a local reconnection layer both in space and laboratory plasmas. While the understanding of the global reconnection dynamics is less developed, notable findings have been made on this issue through detailed documentation of magnetic self-organization phenomena in fusion plasmas. Application of magnetic reconnection physics to astrophysical plasmas is also brie y discussed.

Masaaki Yamada, Russell Kulsrud and Hantao Ji

2009-09-17T23:59:59.000Z

272

Aqueous chemical growth of alpha-Fe2O3-alpha-Cr203 nanocompositethin films  

DOE Green Energy (OSTI)

We are reporting here on the inexpensive fabrication and optical properties of an iron(III) oxide chromium(III) oxide nanocomposite thin film of corundum crystal structure. Its novel and unique-designed architecture consists of uniformed, well-defined and oriented nanorods of Hematite (alpha-Fe2O3) of 50 nm in diameter and 500nm in length and homogeneously distributed nonaggregated monodisperse spherical nanoparticles of Eskolaite (alpha-Cr2O3) of 250 nm in diameter. This alpha-Fe2O3 alpha-Cr2O3 nanocomposite thin film is obtained by growing, directly onto transparent polycrystalline conducting substrate, an oriented layer of hematite nanorods and growing subsequently, the eskolaite layer. The synthesis is carried out by a template-free, low-temperature, multilayer thin film coating process using aqueous solution of metal salts as precursors. Almost 100 percent of the light is absorbed by the composite film between 300 and 525 nm and 40 percent at 800 nm which yields great expectations as photoanode materials for photovoltaic cells and photocatalytic devices.

Vayssieres, Lionel; Guo, Jinghua; Nordgren, Joseph

2001-06-30T23:59:59.000Z

273

CRAD, Training - Oak Ridge National Laboratory TRU ALPHA LLWT Project |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TRU ALPHA LLWT TRU ALPHA LLWT Project CRAD, Training - Oak Ridge National Laboratory TRU ALPHA LLWT Project November 2003 A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a November 2003 assessment of the Training Program portion of an Operational Readiness Review of the Oak Ridge National Laboratory TRU ALPHA LLWT Project. CRADs provide a recommended approach and the types of information to gather to assess elements of a DOE contractor's programs. CRAD, Training - Oak Ridge National Laboratory TRU ALPHA LLWT Project More Documents & Publications CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project

274

GHRS Observations of the Lyman alpha Forest  

E-Print Network (OSTI)

I review the results obtained using the GHRS on low redshift Lyman alpha absorbers. Until the advent of HST and the GHRS, the existence of such absorbers was doubted. The confirmation of their existence, in one of the first GHRS GTO team results to be published, must rank as one of the HSTs most interesting results. The GHRS resolution allows us to probe equivalent widths well below those detectable with the FOS, and has led to a number of interesting new questions. One example is the apparent disagreement between the GHRS result that there are many Lyman alpha absorbers which are not associated with luminous galaxies, and FOS studies which suggest that all such absorbers have a nearby galaxy causing them. This almost certainly shows that the equivalent width (or column density) range reachable by the GHRS includes gas from a wide range of causes, and not only the halos of luminous galaxies. With these data, we are seeing the debris left over from Galaxy formation, material flung out from galaxy interactions and starbursts, and also diffuse halo material at the outer edges of normal galaxies.

Simon L. Morris

1996-10-28T23:59:59.000Z

275

MFTF-. cap alpha. + T progress report  

SciTech Connect

Early in FY 1983, several upgrades of the Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) were proposed to the fusion community. The one most favorably received was designated MFTF-..cap alpha..+T. The engineering design of this device, guided by LLNL, has been a principal activity of the Fusion Engineering Design Center during FY 1983. This interim progress report represents a snapshot of the device design, which was begun in FY 1983 and will continue for several years. The report is organized as a complete design description. Because it is an interim report, some parts are incomplete; they will be supplied as the design study proceeds. As described in this report, MFTF-..cap alpha..+T uses existing facilities, many MFTF-B components, and a number of innovations to improve on the physics parameters of MFTF-B. It burns deuterium-tritium and has a central-cell Q of 2, a wall loading GAMMA/sub n/ of 2 MW/m/sup 2/ (with a central-cell insert module), and an availability of 10%. The machine is fully shielded, allows hands-on maintenance of components outside the vacuum vessel 24 h after shutdown, and has provisions for repair of all operating components.

Nelson, W.D. (ed.)

1985-04-01T23:59:59.000Z

276

Alpha inelastic scattering and cluster structures in {sup 24}Mg  

Science Conference Proceedings (OSTI)

The alpha inelastic scattering from {sup 24}Mg was measured to obtain the isoscalar natural-parity excitation strengths and to search for the {alpha}-condensed states. The multipole decomposition analysis for the measured cross sections was performed. The strength distributions for the {Delta}L = 0-3 were successfully obtained and the possible candidates for the {alpha}-condensed states around the {sup 16}O core were found.

Kawabata, T.; Ishiguro, Y.; Nozawa, Y.; Tomida, N.; Yokota, N. [Department of Physics, Kyoto University (Japan); Adachi, T.; Fujiwara, M.; Hatanaka, K.; Tamii, A.; Yasuda, Y.; Zenihiro, J. [Research Center for Nuclear Physics, Osaka University (Japan); Itoh, M.; Takahashi, T.; Yoshida, H. P. [Cyclotron and Radioisotope Center, Tohoku University (Japan); Maeda, Y.; Miyasako, H.; Saito, T. [Faculty of Engineering, University of Miyazaki (Japan); Matsubara, H.; Sasamoto, Y.; Tokieda, H. [Center for Nuclear Study, University of Tokyo (Japan)

2011-05-06T23:59:59.000Z

277

Stokes IQUV mapping of $\\alpha^2$ CVn & other Ap stars using ESPaDOnS and NARVAL  

E-Print Network (OSTI)

New spectral line polarisation observations of 7 bright Ap stars have been obtained with the ESPaDOnS and Narval high resolution spectropolarimeters (Silvester et al. 2012). The aim of this data set is produce a series of surface magnetic field and surface chemistry maps for these Ap stars. We present new magnetic maps for the Ap star $\\alpha^2$ CVn using these new data and the MDI inversion code INVERS10. $\\alpha^2$ CVn is the first Ap star to be observed during two separate epochs using high resolution phase resolved spectropolarimetric $IQUV$ observations and as such allows us an insight into how stable the surface magnetic structure is over a decade timescale. We show that the new maps give a magnetic field structure consistent with the previous maps obtained by Kochukhov and Wade (2010) from lower quality MuSiCoS spectra taken a decade ago and that the field topology cannot be described by a dipolar or quadrupolar field.

Silvester, J; Wade, G A

2013-01-01T23:59:59.000Z

278

Superconducting calorimetric alpha particle sensors for nuclear nonproliferation applications  

Science Conference Proceedings (OSTI)

Identification of trace nuclear materials is usually accomplished by alpha spectrometry. Current detectors cannot distinguish critical elements and isotopes. We have developed a detector called a microcalorimeter

Robert D. Horansky; Joel N. Ullom; James A. Beall; Gene C. Hilton; Kent D. Irwin; Donald E. Dry; Elizabeth P. Hastings; Stephen P. Lamont; Clifford R. Rudy; Michael W. Rabin

2008-01-01T23:59:59.000Z

279

Progress on Production of Alpha-emitting Radioisotopes for Cancer...  

Office of Science (SC) Website

Progress on Production of Alpha-emitting Radioisotopes for Cancer Therapy Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding...

280

Analysis of alpha Centauri AB including seismic constraints  

E-Print Network (OSTI)

Detailed models of alpha Cen A and B based on new seismological data for alpha Cen B by Carrier & Bourban (2003) have been computed using the Geneva evolution code including atomic diffusion. Taking into account the numerous observational constraints now available for the alpha Cen system, we find a stellar model which is in good agreement with the astrometric, photometric, spectroscopic and asteroseismic data. The global parameters of the alpha Cen system are now firmly constrained to an age of t=6.52+-0.30 Gyr, an initial helium mass fraction Y_i=0.275+-0.010 and an initial metallicity (Z/X)_i=0.0434+-0.0020. Thanks to these numerous observational constraints, we confirm that the mixing-length parameter alpha of the B component is larger than the one of the A component, as already suggested by many authors (Noels et al. 1991, Fernandes & Neuforge 1995 and Guenther & Demarque 2000): alpha_B is about 8% larger than alpha_A (alpha_A=1.83+-0.10 and alpha_B=1.97+-0.10). Moreover, we show that asteroseismic measurements enable to determine the radii of both stars with a very high precision (errors smaller than 0.3%). The radii deduced from seismological data are compatible with the new interferometric results of Kervella et al. (2003) even if they are slightly larger than the interferometric radii (differences smaller than 1%).

P. Eggenberger; C. Charbonnel; S. Talon; G. Meynet; A. Maeder; F. Carrier; G. Bourban

2004-01-29T23:59:59.000Z

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281

Crystallographic variant selection in {alpha}-{beta} brass  

Science Conference Proceedings (OSTI)

The transformation texture of {alpha}/{beta} brass with a diffusional Widmanstaetten {alpha} growth morphology has been investigated. Electron micrographs and electron backscattered diffraction was used to determine that the orientation relationship between the {beta} phase and the {alpha} associated with nucleation at {beta} grain boundaries was 44.3 deg . Crystallographic variant selection was observed across those prior {beta}/{beta} grain boundaries, but this has little effect on the transformation texture due to the crystal symmetry. The effect of the crystallographic variant selection on texture is further weakened by nucleation of diffusional transformed {alpha} in the grain interior.

Stanford, N. [Manchester Materials Science Centre, University of Manchester, Grosvenor Street, Manchester M1 7HS (United Kingdom); Bate, P.S. [Manchester Materials Science Centre, University of Manchester, Grosvenor Street, Manchester M1 7HS (United Kingdom)]. E-mail: pete.bate@man.ac.uk

2005-02-01T23:59:59.000Z

282

Atomistic Modeling of Screw Dislocation Mobility in Alpha-Fe  

Science Conference Proceedings (OSTI)

Register as a New User ... Presentation Title, Atomistic Modeling of Screw Dislocation Mobility in Alpha-Fe. Author(s), Neeraj S. Thirumalai, Peter Gordon, Ju Li, ...

283

Modeling Dislocation Slip Transmission across Alpha-Beta Interface ...  

Science Conference Proceedings (OSTI)

After matching the two GSFs at the alpha-beta interface with Burgers orientation relationship, we perform microscopic phase field simulations. These simulations  ...

284

Weather in stellar atmosphere: the dynamics of mercury clouds in alpha Andromedae  

E-Print Network (OSTI)

The formation of long-lasting structures at the surfaces of stars is commonly ascribed to the action of strong magnetic fields. This paradigm is supported by observations of evolving cool spots in the Sun and active late-type stars, and stationary chemical spots in the early-type magnetic stars. However, results of our seven-year monitoring of mercury spots in non-magnetic early-type star alpha Andromedae show that the picture of magnetically-driven structure formation is fundamentally incomplete. Using an indirect stellar surface mapping technique, we construct a series of 2-D images of starspots and discover a secular evolution of the mercury cloud cover in this star. This remarkable structure formation process, observed for the first time in any star, is plausibly attributed to a non-equilibrium, dynamical evolution of the heavy-element clouds created by atomic diffusion and may have the same underlying physics as the weather patterns on terrestrial and giant planets.

Oleg Kochukhov; Saul J. Adelman; Austin F. Gulliver; Nikolai Piskunov

2007-05-30T23:59:59.000Z

285

Preliminary study of suprathermal alpha particle heating  

SciTech Connect

Some of the consequences of the suprathermal orbits on particle confinement and heating are examined. The guiding-center approximation along with the conservation equations of energy, magnetic moment, and canonical angular momentum were used in the analysis. An example calculation is presented. (MOW)

Miley, G.H.; Petrie, T.W.; Rao, M.P.; Hively, L.H.

1975-01-01T23:59:59.000Z

286

Upgrade of the PNNL TEPC and Multisphere Spectrometer  

SciTech Connect

The Pacific Northwest National Laboratory (PNNL) has used two types of instruments, the tissue equivalent proportional counter (TEPC) and the multisphere spectrometer for characterizing neutron radiation fields in support of neutron dosimetry at the Hanford site. The US Department of Energy recently issued new requirements for radiation protection standards in 10 CFR 835 which affect the way that neutron dose equivalent rates are evaluated. In response to the new requirements, PNNL has upgraded the analyses used in conjunction with the TEPC and multisphere. The analysis software for the TEPC was modified for this effort, and a new analysis code was selected for the multisphere. These new analysis techniques were implemented and tested with measurement data that had been collected in previous measurements. In order to test the effectiveness of the changes, measurements were taken in PNNL’s Low Scatter Room using 252Cf sources in both unmoderated and D2O-moderated configurations that generate well-characterized neutron fields. The instruments were also used at Los Alamos National Laboratory (LANL), in their Neutron Free-in-Air calibration room, also using neutron sources that generate well-characterized neutron fields. The results of the software modifications and the measurements are documented in this report. The TEPC measurements performed at PNNL agreed well with accepted dose equivalent rates using the traditional analysis, agreeing with the accepted value to within 13% for both unmoderated and moderated 252Cf sources. When the new analysis was applied to the TEPC measurement data, the results were high compared to the new accepted value. A similar pattern was seen for TEPC measurements at LANL. Using the traditional analysis method, results for all neutron sources showed good agreement with accepted values, nearly always less than 10%. For the new method of analysis, however, the TEPC responded with higher dose equivalent rates than accepted, by as much as 25%. The reason for the overresponse is that there is very little attenuation of the neutrons by tissue, so it cannot match the effect of attenuation by 1 cm of tissue called for in the new standards. This could be corrected with a modified instrument with a thicker wall, or by analytical means that would need to be developed. The multisphere spectrometer performed reasonably well both at PNNL and at LANL. It could produce a neutron spectrum that was similar to the accepted spectrum, and total flux values were usually within 15% of the accepted values. Dose equivalent rates were usually within 18% of the accepted values. The average energies, however, were usually lower than the accepted values. The performance of this instrument could be much better than seen in this study. If PNNL were to add some moderating spheres to its measurement set and calculate a new set of instrument response functions, performance could be improved. The multisphere could then be a more useful instrument for assessing the dose equivalent rate in the workplace.

Scherpelz, Robert I.; Conrady, Matthew M.

2008-09-10T23:59:59.000Z

287

Airborne Scanning Spectrometer for Remote Sensing of Cloud, Aerosol, Water Vapor, and Surface Properties  

Science Conference Proceedings (OSTI)

An airborne scanning spectrometer was developed for measuring reflected solar and emitted thermal radiation in 50 narrowband channels between 0.55 and 14.2 µm. The instrument provides multispectral images of outgoing radiation for purposes of ...

Michael D. King; W. Paul Menzel; Patrick S. Grant; Jeffrey S. Myers; G. Thomas Arnold; Steven E. Platnick; Liam E. Gumley; Si-Chee Tsay; Christopher C. Moeller; Michael Fitzgerald; Kenneth S. Brown; Fred G. Osterwisch

1996-08-01T23:59:59.000Z

288

Chemical Reaction of Cobalt Clusters with Ethanol by Using FT-ICR Mass Spectrometer  

E-Print Network (OSTI)

Spectrometer Shuhei Inoue*3 and Shigeo Maruyama*4 *3 Dept. of Mech. Sys. Eng., Hiroshima Univ., 1-4-1 Kagamiyama, Higashi-Hiroshima-shi, Hiroshima, 739-8527, Japan *4 Dept. of Mech. Eng., The Univ. of Tokyo, 7

Maruyama, Shigeo

289

Real-Time Detection of Performance Degradation of the Forward-scattering Spectrometer Probe  

Science Conference Proceedings (OSTI)

A method for detecting malfunctions during collection of data with the forward-scattering spectrometer probe (FSSP) is discussed. Droplet spectra measured with the probe are not sufficient to alert operators of probe failures, such as those ...

Jean-Louis Brenguier; A. R. Rodi; G. Gordon; P. Wechsler

1993-02-01T23:59:59.000Z

290

Advances in field-portable mass spectrometers for on-site analytics  

Science Conference Proceedings (OSTI)

Learn how the combination of ambient ionization with portable mass spectroscopy can speed chemical analysis by streamlining sample preparation and throughput requirements. Advances in field-portable mass spectrometers for on-site analytics inform M

291

Theoretical Simulation and Experimental Characterization of an Expansion-Type Kelvin Spectrometer with Intrinsic Calibration  

Science Conference Proceedings (OSTI)

An expansion-type Kelvin spectrometer has been designed and its performance has been shown to agree with the theoretical simulation within experimental uncertainty. In the intrinsically calibrated mode, number concentration as well as ...

W. Holländer; W. Dunkhorst; H. Lödding; H. Windt

2002-11-01T23:59:59.000Z

292

Evaluation of the Forward Scattering Spectrometer Probe. Part III: Time Response and Laser Inhomogeneity Limitations  

Science Conference Proceedings (OSTI)

The electronic response time of the Forward Scattering Spectrometer Probe (FSSP) has been evaluated and is shown to affect the measurement of droplet size. The size of droplets are underestimated when airspeeds exceed 50 m s?1 and size ...

Darrel Baumgardner; Michael Spowart

1990-10-01T23:59:59.000Z

293

A Chemical Ionization Mass Spectrometer for Ground-Based Measurements of Nitric Acid  

Science Conference Proceedings (OSTI)

A chemical ionization mass spectrometer (CIMS) instrument has been developed for high-precision measurements of gaseous nitric acid (HNO3) specifically under high- and variable-humidity conditions in the boundary layer. The instrument’s ...

Kazuyuki Kita; Yu Morino; Yutaka Kondo; Yuichi Komazaki; Nobuyuki Takegawa; Yuzo Miyazaki; Jun Hirokawa; Shigeru Tanaka; Thomas L. Thompson; Ru-Shan Gao; David W. Fahey

2006-08-01T23:59:59.000Z

294

Effects of Coincidence on Measurements with a Forward Scattering Spectrometer Probe  

Science Conference Proceedings (OSTI)

A PMS Forward Scattering Spectrometer Probe (FSSP) may fail to detect a droplet that enters the illuminated volume in coincidence with another droplet, or such a coincident pair may be assigned an erroneous size. This effect is shown to distort ...

William A. Cooper

1988-12-01T23:59:59.000Z

295

Calibration of the Forward-scattering Spectrometer Probe: Modeling Scattering from a Multimode Laser Beam  

Science Conference Proceedings (OSTI)

Scattering calculations using a more detailed model of the multimode laser beam in the forward-scattering spectrometer probe (FSSP) were carried out by using a recently developed extension to Mie scattering theory. From this model, new ...

Edward A. Hovenac; James A. Lock

1993-08-01T23:59:59.000Z

296

Testing and Performance of Two-Dimensional Optical Array Spectrometers with Greyscale  

Science Conference Proceedings (OSTI)

Two laboratory optical array spectrometers with greyscale were evaluated for their sizing, depth of field and timing performance; these three factors are necessary to calculate concentrations and liquid water contents. The probes were of 10 and ...

Paul Joe; Roland List

1987-03-01T23:59:59.000Z

297

Superconducting gamma and fast-neutron spectrometers with high energy resolution  

DOE Patents (OSTI)

Superconducting Gamma-ray and fast-neutron spectrometers with very high energy resolution operated at very low temperatures are provided. The sensor consists of a bulk absorber and a superconducting thermometer weakly coupled to a cold reservoir, and determines the energy of the incident particle from the rise in temperature upon absorption. A superconducting film operated at the transition between its superconducting and its normal state is used as the thermometer, and sensor operation at reservoir temperatures around 0.1 K reduces thermal fluctuations and thus enables very high energy resolution. Depending on the choice of absorber material, the spectrometer can be configured either as a Gamma-spectrometer or as a fast-neutron spectrometer.

Friedrich, Stephan (San Jose, CA); , Niedermayr, Thomas R. (Oakland, CA); Labov, Simon E. (Berkeley, CA)

2008-11-04T23:59:59.000Z

298

Some numerical reslts on best uniform polynomial approximation of. chi. sup. alpha. on (0,1)  

Science Conference Proceedings (OSTI)

Let {alpha} be a positive number, and let E{sub n}(chi{sup {alpha}}; (0,1)) denote the error of best uniform approximation to {chi}{sup {alpha}}, by polynomials of degree at most n, on the interval (0,1). The Russian mathematician S.N. Bernstein established the existence of a nonnegative constant {Beta}({alpha}) such that {Beta}({alpha}):= {sub n{yields}{infinity}lim(2n){sup 2{alpha}}E{sub n}({chi}{sup {alpha}};(0.1)). In addition, Bernstein showed that {Beta}{alpha} 0) and that {Gamma}(2{alpha}){vert bar}sin({pi}{alpha}){vert bar}/{pi} (1{minus}1/2{alpha}{minus}1) {1/2}), so that the asymptotic behavior of {Beta}({alpha}) is known when {alpha}{yields}{infinity}. Still, the problem of trying to determine {Beta}({alpha}) more precisely, for all {alpha} > 0, is intriguing. To this end, we have rigorously determined the numbers for thirteen values of {alpha}, where these numbers were calculated with a precision of at least 200 significant digits. For each of these thirteen values of {alpha}, Richardson's extrapolation was applied to the products to obtain estimates of {Beta}({alpha}) to approximately 40 decimal places. Included are graphs of the points ({alpha},{Beta}({alpha})) for the thirteen values of {alpha} that we considered.

Carpenter, A.J.; Varga, R.S.

1992-01-01T23:59:59.000Z

299

Influence of primordial magnetic fields on 21 cm emission  

E-Print Network (OSTI)

Magnetic fields in the early universe can significantly alter the thermal evolution and the ionization history during the dark ages. This is reflected in the 21 cm line of atomic hydrogen, which is coupled to the gas temperature through collisions at high redshifts, and through the Wouthuysen-Field effect at low redshifts. We present a semi-analytic model for star formation and the build-up of a Lyman alpha background in the presence of magnetic fields, and calculate the evolution of the mean 21 cm brightness temperature and its frequency gradient as a function of redshift. We further discuss the evolution of linear fluctuations in temperature and ionization in the presence of magnetic fields and calculate the effect on the 21 cm power spectrum. At high redshifts, the signal is increased compared to the non-magnetic case due to the additional heat input into the IGM from ambipolar diffusion and the decay of MHD turbulence. At lower redshifts, the formation of luminous objects and the build-up of a Lyman alpha background can be delayed by a redshift interval of 10 due to the strong increase of the filtering mass scale in the presence of magnetic fields. This tends to decrease the 21 cm signal compared to the zero-field case. In summary, we find that 21 cm observations may become a promising tool to constrain primordial magnetic fields.

Dominik R. G. Schleicher; Robi Banerjee; Ralf S. Klessen

2008-08-11T23:59:59.000Z

300

Atomic data for the ITER Core Imaging X-ray Spectrometer  

SciTech Connect

The parameters of the ITER core plasmas will be measured using the Core Imaging X-ray Spectrometer (CIXS), a high-resolution crystal spectrometer focusing on the L-shell spectra of highly ionized tungsten atoms. In order to correctly infer the plasma properties accurate atomic data are required. Here, some aspects of the underlying physics are discussed using experimental data and theoretical predictions from modeling.

Clementson, J; Beiersdorfer, P; Biedermann, C; Bitter, M; Delgado-Aparicio, L F; Graf, A; Gu, M F; Hill, K W; Barnsley, R

2012-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Testing of an Echelle Spectrometer as a LIBS Detector at Sandia  

Science Conference Proceedings (OSTI)

Some useful information has been obtained regarding the potential use of the echelle spectrometer system for Laser-Induced Breakdown Spectroscopy (LIBS) monitoring applications, despite the AOTF-computer operational problems during the Sandia site-test. Currently, the use of the echelle spectrometer with the LIBS system is not suitable for trace-level analyte detection. This is due, in part, to the lower light throughput of the echelle spectrometer system compared to the SpectraPro-275. The low duty cycle of the LIBS system, which results from the use of a low-repetition-rate (but low-cost and portable) laser, also limits the detection sensitivity achievable using a high-resolution spectrometer. At high analyte concentrations, the echelle spectrometer is able to resolve spectral interferences including the Cd-As line pair at 228.8-nm and other LIBS emission features not resolved using the SpectraPro-275. A definite positive result obtained is the determination that at the high resolution of the echelle spectrometer, time-gating of the CCD detector is not necessary to discriminate analyte spectral signals from the LIBS background emission. The cost of the gated CCD and associated electronics is a significant portion of the cost of the Sandia LIBS system. Incorporation of a low-cost version of the echelle spectrometer for process monitoring applications not requiring trace-level detection could make LIBS a more viable technique where cost is a limiting factor. We hope to have the opportunity to perform additional collaborative work using the AOTF-echelle spectrometer for on-line LIBS monitoring applications, in order to demonstrate the advantage of rapid line-switching (using the AOTF) and simultaneous detection of multiple emission features across the spectral range of the echelle.

David P. Baldwin; Daniel S. Zamzow; David K. Ottesen; Howard A. Johnsen

2001-04-25T23:59:59.000Z

302

Summary of alpha-neutron sources in GADRAS.  

SciTech Connect

A common source of neutrons for calibration and testing is alpha-neutron material, named for the alpha-neutron nuclear reaction that occurs within. This material contains a long-lived alpha-emitter and a lighter target element. When the alpha particle from the emitter is absorbed by the target, neutrons and gamma rays are released. Gamma Detector Response and Analysis Software (GADRAS) includes built-in alpha-neutron source definitions for AcC, AmB, AmBe, AmF, AmLi, CmC, and PuC. In addition, GADRAS users may create their own alpha-neutron sources by placing valid alpha-emitters and target elements in materials within their one-dimensional models (1DModel). GADRAS has the ability to use pre-built alpha-neutron sources for plotting or as trace-sources in 1D models. In addition, if any material (existing or user-defined) specified in a 1D model contains both an alpha emitter in conjunction with a target nuclide, or there is an interface between such materials, then the appropriate neutron-emission rate from the alpha-neutron reaction will be computed. The gamma-emissions from these sources are also computed, but are limited to a subset of nine target nuclides. If a user has experimental data to contribute to the alpha-neutron gamma emission database, it may be added directly or submitted to the GADRAS developers for inclusion. The gadras.exe.config file will be replaced when GADRAS updates are installed, so sending the information to the GADRAS developers is the preferred method for updating the database. This is also preferable because it enables other users to benefit from your efforts.

Mitchell, Dean James; Thoreson, Gregory G.; Harding, Lee T.

2012-05-01T23:59:59.000Z

303

Reconstruction of Neutral Hydrogen Density Profiles in HANBIT Magnetic Mirror Device Using Bayesian Probability Theory  

SciTech Connect

Hydrogen is the main constitute of plasmas in HANBIT magnetic mirror device, therefore, measurement of the emission from excited levels of hydrogen atoms is an important diagnostic tool. From the emissivity of H{sub {alpha}} radiation one can derive quantities such as the neutral hydrogen density and the source rate. An unbiased and consistent probability theory based approach within the framework of Bayesian inference is applied to the reconstruction of H{sub {alpha}} emissivity profiles and hydrogen neutral density profiles in HANBIT magnetic mirror device.

Yoon, J.-S.; Seo, D.-C.; Na, H.-K.; Yoon, S.-W. [Korea Basic Science Institute (Korea, Republic of)

2005-01-15T23:59:59.000Z

304

Superconducting magnet  

DOE Patents (OSTI)

A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

Satti, John A. (Naperville, IL)

1980-01-01T23:59:59.000Z

305

Magnet innovations for linacs  

Science Conference Proceedings (OSTI)

It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results will be presented about past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs.

Halbach, K.

1986-06-01T23:59:59.000Z

306

Lower hybrid instability driven by mono-energy {alpha}-particles with finite pitch angle spread in a plasma  

Science Conference Proceedings (OSTI)

A kinetic formalism of lower hybrid wave instability, driven by mono-energy {alpha}-particles with finite pitch angle spread, is developed. The instability arises through cyclotron resonance interaction with high cyclotron harmonics of {alpha}-particles. The {alpha}-particles produced in D-T fusion reactions have huge Larmor radii ({approx}10 cm) as compared to the wavelength of the lower hybrid wave, whereas their speed is an order of magnitude smaller than the speed of light in vacuum. As a result, large parallel phase velocity lower hybrid waves, suitable for current drive in tokamak, are driven unstable via coupling to high cyclotron harmonics. The growth rate decreases with increase in pitch angle spread of the beam. At typical electron density of {approx}10{sup 19} m{sup -3}, magnetic field {approx}4 Tesla and {alpha}-particle concentration {approx}0.1%, the large parallel phase velocity lower hybrid wave grows on the time scale of 20 ion cyclotron periods. The growth rate decreases with plasma density.

Kumar, Pawan; Singh, Vishwesh; Tripathi, V. K. [Department of Physics, IIT Delhi, New Delhi-110016 (India)

2013-02-15T23:59:59.000Z

307

A Performance Evaluation of an Alpha EV7 Processing Node  

Science Conference Proceedings (OSTI)

In this paper we detail the performance of a new Alpha-Server node containing 16 Alpha EV7 CPUs. The EV7 processor is based on the EV68 processor core that is used in terascale systems at Los Alamos National Laboratory and the Pittsburgh Supercomputing ... Keywords: Performance, analysis, application performance, communication performance, high performance computing, memory performance

Darren J. Kerbyson; Adolfy Hoisie; Scott Pakin; Fabrizio Petrini; Harvey J. Wasserman

2004-05-01T23:59:59.000Z

308

TAE SATURATION OF ALPHA PARTICLE DRIVEN INSTABILITY IN TFTR \\Lambda  

E-Print Network (OSTI)

. B. White, Princeton Plasma Physics Laboratory Princeton University, Princeton, New Jersey 08543 H. L by the fusion produced alpha particles. In this paper we apply a recently developed nonlinear theory of kinetic induced by alpha particles includ­ ing FOW and FLR effects [8]. Additional calculation had been added

309

CRAD, Radiological Controls - Oak Ridge National Laboratory TRU ALPHA LLWT  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TRU TRU ALPHA LLWT Project CRAD, Radiological Controls - Oak Ridge National Laboratory TRU ALPHA LLWT Project November 2003 A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a November 2003 assessment of the Radiation Protection Program portion of an Operational Readiness Review of the Oak Ridge National Laboratory TRU ALPHA LLWT Project. CRADs provide a recommended approach and the types of information to gather to assess elements of a DOE contractor's programs. CRAD, Radiological Controls - Oak Ridge National Laboratory TRU ALPHA LLWT Project More Documents & Publications CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT

310

CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Quality Assurance - Oak Ridge National Laboratory TRU ALPHA Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project November 2003 A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a November 2003 assessment of the Quality Assurance Program portion of an Operational Readiness Review of the Oak Ridge National Laboratory TRU ALPHA LLWT Project. CRADs provide a recommended approach and the types of information to gather to assess elements of a DOE contractor's programs. CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project More Documents & Publications

311

Effects of alpha populations on tokamak ballooning stability  

SciTech Connect

Fusion product alpha populations can significantly influence tokamak stability due to coupling between the trapped alpha precessional drift and the kinetic ballooning mode frequency. This effect is of particular importance in parameter regimes where the alpha pressure gradient begins to constitute a sizable fraction of the thermal plasma pressure gradient. Careful, quantitative evaluations of these effects are necessary in burning plasma devices such as the Tokamak Fusion Test Reactor and the Joint European Torus, and we have continued systematic development of such a kinetic stability model. In this model we have considered a range of different forms for the alpha distribution function and the tokamak equilibrium. Both Maxwellian and slowing-down models have been used for the alpha energy dependence while deeply trapped and, more recently, isotropic pitch angle dependence have been examined.

Spong, D.A.; Sigmar, D.J.; Tsang, K.T.; Ramos, J.J.; Hastings, D.E.; Cooper, W.A.

1986-01-01T23:59:59.000Z

312

The molecular biology and biochemistry of rice endosperm. alpha. -globulin  

SciTech Connect

The author's first objective was to isolate a cDNA clone that encodes the rice endosperm {alpha}-globulin. Purified antibodies against a rice storage protein, {alpha}-globulin, were used to screen a {lambda}gt11 cDNA expression library constructed from immature rice seed endosperm. The cDNA insert of clone 4A1 (identified by antibody screening) was used as a probe to identify long cDNA inserts in the library. The deduced amino acid sequence of clone A3-12 cDNA insert (identified by cDNA screening) contained the amino acid sequences of three cyanogen bromide peptides fragment of {alpha}-globulin. The calculated molecular weight and amino acid composition of the deduced amino acid sequence were similar to the {alpha}-globulin protein. Northern blot analysis indicated that mRNA of one size, approximately 1.0 kb, is expressed. Southern genomic blot analysis revealed one band with EcoRI or Hind III digestion. Cell-free translation and immunoprecipitation showed that the initial translation product is approximately 2,000 daltons larger than the mature protein. The amino acid sequence of {alpha}-globulin revealed limited regions of similarities with wheat storage proteins. The author concludes that the cDNA insert in clone A3-12 contained the entire coding region of {alpha}-globulin protein and that {alpha}-globulin is encoded by a single gene. My second objective was to inhibit the degradation of {alpha}-globulin in the salt extract of rice flour. The salt extract of rice flour contained an acid protease whose optimal pH was 3 for {sup 3}H-casein hydrolysis. A polypeptide with molecular weight of 20,000 was immunologically reactive with {alpha}-globulin antibodies and is produced by limited proteolysis in the extract. Pepstatin inhibited the proteolysis of 3H-casein and slowed the proteolysis of {alpha}-globulin.

Shorrosh, B.S.

1989-01-01T23:59:59.000Z

313

Magnetics and the body  

NLE Websites -- All DOE Office Websites (Extended Search)

no magnetic "charges"), such as from electromagnets. Magnetic fields are measured in Tesla (T) or Gauss (G). The Tesla is a very large unit (1 T 10,000 G). Most large magnets...

314

Learning About Magnets!  

NLE Websites -- All DOE Office Websites (Extended Search)

the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force...

315

ALS superbend magnet system  

E-Print Network (OSTI)

ALS Superbend Magnet System J. Zbasnik † , S. T. Wang †† ,of a High-Field Magnet for the ALS,” Transactions AppliedRefrigeration options for the ALS Superbend dipole magnets”,

2000-01-01T23:59:59.000Z

316

Helical Magnets Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC, the basic construction unit is a superconducting dipole magnet producing a four tesla dipole field that rotates through 360 degrees in a length of 2.4 meters. The magnets...

317

THE ACCELERATION OF IONS IN SOLAR FLARES DURING MAGNETIC RECONNECTION  

Science Conference Proceedings (OSTI)

The acceleration of solar flare ions during magnetic reconnection is explored via particle-in-cell simulations that self-consistently and simultaneously follow the motions of both protons and {alpha} particles. We show that the dominant heating of thermal ions during guide field reconnection, the usual type in the solar corona, results from pickup behavior during the entry into reconnection exhausts. In contrast to anti-parallel reconnection, the temperature increment is dominantly transverse, rather than parallel, to the local magnetic field. A comparison of protons and {alpha} reveals a mass-to-charge (M/Q) threshold in pickup behavior that favors the heating of high-M/Q ions, which is consistent with impulsive flare observations.

Knizhnik, K. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Swisdak, M.; Drake, J. F., E-mail: kknizhni@pha.jhu.edu, E-mail: swisdak@umd.edu, E-mail: drake@umd.edu [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States)

2011-12-20T23:59:59.000Z

318

Magnetization of neutron matter  

SciTech Connect

In this paper, we compute magnetization of neutron matter at strong magnetic field using the lowest order constrained variational (LOCV) technique.

Bigdeli, M. [Department of Physics, Zanjan University, P.O. Box 45195-313, Zanjan (Iran, Islamic Republic of)

2011-09-21T23:59:59.000Z

319

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network (OSTI)

Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

Hassenzahl, W.

2011-01-01T23:59:59.000Z

320

Magnetic Materials Group Homepage  

Science Conference Proceedings (OSTI)

... and simulation to become the driving force in ... develop a real-time magnetic domain imaging ... data-storage and permanent magnets with increased ...

2012-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

NSLS II: Magnetism  

NLE Websites -- All DOE Office Websites (Extended Search)

spatial ordering of the magnetic moments that is superimposed on the crystal lattice. Why these atomic magnetic moments survive and how they arrange in the solid is the...

322

Regenerator for Magnetic Refrigerants  

Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators.

323

Search for antideuterons and strangelets in cosmic rays with AMS-01  

E-Print Network (OSTI)

AMS (the Alpha Magnetic Spectrometer) is a high-energy particle detector in space. An engineer- ing version of AMS, AMS-01, flew on the space shuttle Discovery for ten days in June 1998 and collected 108 cosmic ray events. ...

Henning, Reyco, 1975-

2004-01-01T23:59:59.000Z

324

CONSTRAINING PRIMORDIAL MAGNETIC FIELDS THROUGH LARGE-SCALE STRUCTURE  

Science Conference Proceedings (OSTI)

We study primordial magnetic field effects on the matter perturbations in the universe. We assume magnetic field generation prior to the big bang nucleosynthesis (BBN), i.e., during the radiation-dominated epoch of the universe expansion, but do not limit analysis by considering a particular magnetogenesis scenario. Contrary to previous studies, we limit the total magnetic field energy density and not the smoothed amplitude of the magnetic field at large (of the order of 1 Mpc) scales. We review several cosmological signatures, such as halo abundance, thermal Sunyaev-Zel'dovich effect, and Ly{alpha} data. For a cross-check, we compare our limits with that obtained through the cosmic microwave background faraday rotation effect and BBN. The limits range between 1.5 nG and 4.5 nG for n{sub B} in (- 3; -1.5).

Kahniashvili, Tina; Natarajan, Aravind; Battaglia, Nicholas [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Maravin, Yurii [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, KS 66506 (United States); Tevzadze, Alexander G., E-mail: tinatin@andrew.cmu.edu [Faculty of Exact and Natural Sciences, Javakhishvili Tbilisi State University, 3 Chavchavadze Avenue, Tbilisi 0128 (Georgia)

2013-06-10T23:59:59.000Z

325

DYNAMICS OF CHROMOSPHERIC UPFLOWS AND UNDERLYING MAGNETIC FIELDS  

SciTech Connect

We used H{alpha}-0.1 nm and magnetic field (at 1.56{mu}) data obtained with the New Solar Telescope to study the origin of the disk counterparts to type II spicules, so-called rapid blueshifted excursions (RBEs). The high time cadence of our chromospheric (10 s) and magnetic field (45 s) data allowed us to generate x-t plots using slits parallel to the spines of the RBEs. These plots, along with potential field extrapolation, led us to suggest that the occurrence of RBEs is generally correlated with the appearance of new, mixed, or unipolar fields in close proximity to network fields. RBEs show a tendency to occur at the interface between large-scale fields and small-scale dynamic magnetic loops and thus are likely to be associated with the existence of a magnetic canopy. Detection of kinked and/or inverse {sup Y-}shaped RBEs further confirm this conclusion.

Yurchyshyn, V.; Abramenko, V.; Goode, P. [Big Bear Solar Observatory, New Jersey Institute of Technology, Big Bear City, CA 92314 (United States)] [Big Bear Solar Observatory, New Jersey Institute of Technology, Big Bear City, CA 92314 (United States)

2013-04-10T23:59:59.000Z

326

FLARES AND THEIR UNDERLYING MAGNETIC COMPLEXITY  

Science Conference Proceedings (OSTI)

SphinX (Solar PHotometer IN X-rays), a full-disk-integrated spectrometer, observed 137 flare-like/transient events with active region (AR) 11024 being the only AR on disk. The Hinode X-Ray Telescope (XRT) and Solar Optical Telescope observe 67 of these events and identified their location from 12:00 UT on July 3 through 24:00 UT 2009 July 7. We find that the predominant mechanisms for flares observed by XRT are (1) flux cancellation and (2) the shearing of underlying magnetic elements. Point- and cusp-like flare morphologies seen by XRT all occur in a magnetic environment where one polarity is impeded by the opposite polarity and vice versa, forcing the flux cancellation process. The shearing is either caused by flux emergence at the center of the AR and separation of polarities along a neutral line or by individual magnetic elements having a rotational motion. Both mechanisms are observed to contribute to single- and multiple-loop flares. We observe that most loop flares occur along a large portion of a polarity inversion line. Point- and cusp-like flares become more infrequent as the AR becomes organized with separation of the positive and negative polarities. SphinX, which allows us to identify when these flares occur, provides us with a statistically significant temperature and emission scaling law for A and B class flares: EM = 6.1 x 10{sup 33} T{sup 1.9{+-}0.1}.

Engell, Alexander J.; Golub, Leon; Korreck, Kelly [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge MA 02138 (United States); Siarkowski, Marek; Gryciuk, Magda; Sylwester, Janusz; Sylwester, Barbara [Space Research Center, Polish Academy of Sciences, Kopernika 11, 51-622 Wroclaw (Poland); Cirtain, Jonathan, E-mail: aengell@cfa.harvard.edu [Marshall Space Flight Center NASA, Mail Code: VP62, Marshall Space Flight Center, AL 35812 (United States)

2011-01-01T23:59:59.000Z

327

Agent Tcl: Alpha Release 1.1  

E-Print Network (OSTI)

Agent Tcl is a transportable agent system. The agents are written in an extended version of the Tool Command Lanuage (Tcl). Each agent can suspend its execution at an arbitrary point, transport to another machine and resume execution on the new machine. This migration is accomplished with the agent jump command. agent jump captures the current state of the Tcl script and transfers this state to the destination machine. The state is restored on the new machine and the Tcl script continues its execution from the command immediately after the agent jump. In addition to migration, agents can send messages to each other and can establish direct connections. A direct connection is more efficient than message passing for bulk data transfer. Finally, agents can use the Tk toolkit to create graphical user interfaces on their current machine. Agent Tcl is implemented as two components. The first component is an extended Tcl interpreter. The second component is a server which runs on each machine. The server accepts incoming agents, messages and connection requests and keeps track of the agents that are running on its machine. An alpha release of Agent Tcl is available for public use. This documentation describes how to obtain and compile the source code, how to run the server and how to write transportable agents.

Robert Gray Department; Robert S. Gray

1995-01-01T23:59:59.000Z

328

1. LEARNING FROM THE PIPER ALPHA  

E-Print Network (OSTI)

people and cost billions of dollars in property damage. It was caused by a massive fire, which was not the result of an unpredictable “act of God ” but of an accumulation of errors and questionable decisions. Most of them were rooted in the organization, its structure, procedures, and culture. This paper analyzes the accident scenario using the risk analysis framework, determines which human decision and actions influenced the occurrence of the basic events, and then identifies the organizational roots of these decisions and actions. These organizational factors are generalizable to other industries and engineering systems. They include flaws in the design guidelines and design practices (e.g., tight physical couplings or insufficient redundancies), misguided priorities in the management of the tradeoff between productivity and safety, mistakes in the management of the personnel on board, and errors of judgment in the process by which financial pressures are applied on the production sector (i.e., the oil companies ’ definition of profit centers) resulting in deficiencies in inspection and maintenance operations. This analytical approach allows identification of risk management measures that go beyond the purely technical (e.g., add redundancies to a safety system) and also include improvements of management practices. KEY WORDS: Piper Alpha accident; offshore platforms; human error; organizational errors; postmortem analysis; probabilistic risk analysis.

M. Elisabeth Patc-cornell

1992-01-01T23:59:59.000Z

329

Some numerical reslts on best uniform polynomial approximation of {chi}{sup {alpha}} on [0,1  

SciTech Connect

Let {alpha} be a positive number, and let E{sub n}(chi{sup {alpha}}; [0,1]) denote the error of best uniform approximation to {chi}{sup {alpha}}, by polynomials of degree at most n, on the interval [0,1]. The Russian mathematician S.N. Bernstein established the existence of a nonnegative constant {Beta}({alpha}) such that {Beta}({alpha}):= {sub n{yields}{infinity}lim(2n){sup 2{alpha}}E{sub n}({chi}{sup {alpha}};[0.1]). In addition, Bernstein showed that {Beta}{alpha} < {Gamma}(2{alpha}){vert_bar}sin(pi}{alpha}){vert_bar}/{pi} ({alpha} > 0) and that {Gamma}(2{alpha}){vert_bar}sin({pi}{alpha}){vert_bar}/{pi} (1{minus}1/2{alpha}{minus}1) < {Beta}({alpha}) ({alpha} > {1/2}), so that the asymptotic behavior of {Beta}({alpha}) is known when {alpha}{yields}{infinity}. Still, the problem of trying to determine {Beta}({alpha}) more precisely, for all {alpha} > 0, is intriguing. To this end, we have rigorously determined the numbers for thirteen values of {alpha}, where these numbers were calculated with a precision of at least 200 significant digits. For each of these thirteen values of {alpha}, Richardson`s extrapolation was applied to the products to obtain estimates of {Beta}({alpha}) to approximately 40 decimal places. Included are graphs of the points ({alpha},{Beta}({alpha})) for the thirteen values of {alpha} that we considered.

Carpenter, A.J.; Varga, R.S.

1992-07-01T23:59:59.000Z

330

Alpha migration through air filters: A numerical simulation  

Science Conference Proceedings (OSTI)

This theoretical study investigates the migration of alpha-emitting particles through high-efficiency particulate air (HEPA) filters. As part of the study, a review of previous research relating to the alpha-migration phenomena was conducted. As a result of the literature review, a numerical model was developed to simulate the migration of alpha-emitting radionuclide aerosols through HEPA filters. This model predicts the filter performance with regard to particle penetration. It can be used to better estimate the penetration of alpha radioactive species through filter systems for environmental concerns, to aid in the use of current filter systems, and to design new filter systems. It is obvious from the review of the literature that evidence exists of migration of alpha radionuclide species through high-efficiency filter media. The theories suggest that nanometer-size particles can eventually penetrate fibrous filters because of gradual movement through the filter matrix. It is conjectured that this movement may be induced by energies caused by the alpha recoil from the decay process by thermal energies. It is further hypothesized that such nanometer-size particles, containing radionuclide species can be formed from larger particles already captured within the filter. The penetration of such small particles through high-efficiency filter media is so low that experimental corroboration of these mechanisms by penetration measurements is difficult at best. A number of items were identified that affect the migration of alpha-emitting particles through a filter. These include the size distribution of aerosol particles entering the filter, the size distribution of fragment particles produced by alpha recoil, the penetration of the challenge aerosols and fragment particles, the velocity through the filter, the radionuclide specific activity, the alpha recoil energy, and the surface-binding energies between the particle and the filter matrix.

Biermann, A.H.; da Roza, R.A.; Chang, Yun.

1991-12-11T23:59:59.000Z

331

H{alpha} ABSORPTION IN TRANSITING EXOPLANET ATMOSPHERES  

SciTech Connect

Absorption of stellar H{alpha} by the upper atmosphere of the planet HD 189733b has recently been detected by Jensen et al. Motivated by this observation, we have developed a model for atomic hydrogen in the n = 2 state and compared the resulting H{alpha} line profile to the observations. The model atmosphere is in hydrostatic balance, as well as thermal and photoionization equilibrium. Collisional and radiative transitions are included in the determination of the n = 2 state level population. We find that H{alpha} absorption is dominated by an optical depth {tau} {approx} 1 shell, composed of hydrogen in the metastable 2s state that is located below the hydrogen ionization layer. The number density of the 2s state within the shell is found to vary slowly with radius, while that of the 1s state falls rapidly. Thus while the Ly{alpha} absorption, for a certain wavelength, occurs inside a relatively well defined impact parameter, the contribution to H{alpha} absorption is roughly uniform over the entire atomic hydrogen layer. The model can approximately reproduce the observed Ly{alpha} and H{alpha} integrated transit depths for HD 189733b by using an ionization rate enhanced over that expected for the star by an order of magnitude. For HD 209458b, we are unable to explain the asymmetric H{alpha} line profile observed by Jensen et al., as the model produces a symmetric line profile with transit depth comparable to that of HD 189733b. In an appendix, we study the effect of the stellar Ly{alpha} absorption on the net cooling rate.

Christie, Duncan; Arras, Phil; Li Zhiyun, E-mail: dac5zm@virginia.edu, E-mail: pla7y@virginia.edu, E-mail: zl4h@virginia.edu [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

2013-08-01T23:59:59.000Z

332

Neutron response of the LAMBDA spectrometer and neutron interaction length in BaF2  

E-Print Network (OSTI)

We report on the neutron response of the LAMBDA spectrometer developed earlier for high-energy gamma-ray measurement. The energy dependent neutron detection efficiency of the spectrometer has been measured using the time-of-flight (TOF) technique and compared with that of an organic liquid scintillator based neutron detector (BC501A). The extracted efficiencies have also been compared with those obtained from Monte Carlo GEANT4 simulation. We have also measured the average interaction length of neutrons in the BaF2 crystal in a separate experiment, in order to determine the TOF energy resolution. Finally, the LAMBDA spectrometer has been tested in an in-beam-experiment by measuring neutron energy spectra in the 4He + 93Nb reaction to extract nuclear level density parameters. Nuclear level density parameters obtained by the LAMBDA spectrometer were found to be consistent with those obtained by the BC501A neutron detector, indicating that the spectrometer can be efficiently used as a neutron detector to measure the nuclear level density parameter.

Balaram Dey; Debasish Mondal; Deepak Pandit; S. Mukhopadhyay; Surajit Pal; K. Banerjee; Srijit Bhattacharya; A. De; S. R. Banerjee

2013-06-17T23:59:59.000Z

333

Selective flow path alpha particle detector and method of use  

DOE Patents (OSTI)

A method and apparatus for monitoring alpha contamination are provided in which ions generated in the air surrounding the item, by the passage of alpha particles, are moved to a distant detector location. The parts of the item from which ions are withdrawn can be controlled by restricting the air flow over different portions of the apparatus. In this way, detection of internal and external surfaces separately, for instance, can be provided. The apparatus and method are particularly suited for use in undertaking alpha contamination measurements during the commissioning operations.

Orr, Christopher Henry (Sellafield, Seascale, Cumbria, GB); Luff, Craig Janson (Sellafield, Seascale, Cumbria, GB); Dockray, Thomas (Sellafield, Seascale, Cumbria, GB); Macarthur, Duncan Whittemore (P.O. Box 1663, Los Alamos, NM 87545)

2002-01-01T23:59:59.000Z

334

Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN  

E-Print Network (OSTI)

We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at the Planck Scale. We discuss some of the particle detection techniques used in ALPHA. Preliminary results from commissioning studies of a partial system of the ALPHA Si vertex detector are presented, the results of which highlight the power of annihilation vertex detection capability in antihydrogen studies.

Fujiwara, M C; Bertsche, W; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Lai, W; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wasilenko, L; Wurtele, J S; Yamazaki, Y

2008-01-01T23:59:59.000Z

335

Single and double grid long-range alpha detectors  

DOE Patents (OSTI)

Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring.

MacArthur, Duncan W. (Los Alamos, NM); Allander, Krag S. (Ojo Caliente, NM)

1993-01-01T23:59:59.000Z

336

Single and double grid long-range alpha detectors  

DOE Patents (OSTI)

Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring.

MacArthur, D.W.; Allander, K.S.

1993-03-16T23:59:59.000Z

337

Magnetic Energy and Helicity Budgets in the Active-Region Solar Corona. I. Linear Force-Free Approximation  

E-Print Network (OSTI)

We self-consistently derive the magnetic energy and relative magnetic helicity budgets of a three-dimensional linear force-free magnetic structure rooted in a lower boundary plane. For the potential magnetic energy we derive a general expression that gives results practically equivalent to those of the magnetic Virial theorem. All magnetic energy and helicity budgets are formulated in terms of surface integrals applied to the lower boundary, thus avoiding computationally intensive three-dimensional magnetic field extrapolations. We analytically and numerically connect our derivations with classical expressions for the magnetic energy and helicity, thus presenting a so-far lacking unified treatment of the energy/helicity budgets in the constant-alpha approximation. Applying our derivations to photospheric vector magnetograms of an eruptive and a noneruptive solar active regions, we find that the most profound quantitative difference between these regions lies in the estimated free magnetic energy and relative magnetic helicity budgets. If this result is verified with a large number of active regions, it will advance our understanding of solar eruptive phenomena. We also find that the constant-alpha approximation gives rise to large uncertainties in the calculation of the free magnetic energy and the relative magnetic helicity. Therefore, care must be exercised when this approximation is applied to photospheric magnetic field observations. Despite its shortcomings, the constant-alpha approximation is adopted here because this study will form the basis of a comprehensive nonlinear force-free description of the energetics and helicity in the active-region solar corona, which is our ultimate objective.

M. K. Georgoulis; Barry J. LaBonte

2007-06-27T23:59:59.000Z

338

Magnetic Energy and Helicity Budgets in the Active-Region Solar Corona. I. Linear Force-Free Approximation  

E-Print Network (OSTI)

We self-consistently derive the magnetic energy and relative magnetic helicity budgets of a three-dimensional linear force-free magnetic structure rooted in a lower boundary plane. For the potential magnetic energy we derive a general expression that gives results practically equivalent to those of the magnetic Virial theorem. All magnetic energy and helicity budgets are formulated in terms of surface integrals applied to the lower boundary, thus avoiding computationally intensive three-dimensional magnetic field extrapolations. We analytically and numerically connect our derivations with classical expressions for the magnetic energy and helicity, thus presenting a so-far lacking unified treatment of the energy/helicity budgets in the constant-alpha approximation. Applying our derivations to photospheric vector magnetograms of an eruptive and a noneruptive solar active regions, we find that the most profound quantitative difference between these regions lies in the estimated free magnetic energy and relative magnetic helicity budgets. If this result is verified with a large number of active regions, it will advance our understanding of solar eruptive phenomena. We also find that the constant-alpha approximation gives rise to large uncertainties in the calculation of the free magnetic energy and the relative magnetic helicity. Therefore, care must be exercised when this approximation is applied to photospheric magnetic field observations. Despite its shortcomings, the constant-alpha approximation is adopted here because this study will form the basis of a comprehensive nonlinear force-free description of the energetics and helicity in the active-region solar corona, which is our ultimate objective.

Manolis K. Georgoulis; Barry J. Labonte

2005-01-01T23:59:59.000Z

339

Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source  

SciTech Connect

We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

Bakeman, M. S. [Department of Physics, University of Nevada Reno, Reno, Nevada 89557 (United States); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Tilborg, J. van; Sokollik, T.; Baum, D.; Ybarrolaza, N.; Duarte, R.; Toth, C.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2010-10-15T23:59:59.000Z

340

Temperature and nonlinearity corrections for a photodiode array spectrometer used in the field  

SciTech Connect

Temperature and nonlinearity effects are two important factors that limit the use of photodiode array spectrometers. Usually the spectrometer is calibrated at a known temperature against a reference source of a particular spectral radiance, and then it is used at different temperatures to measure sources of different spectral radiances. These factors are expected to be problematic for nontemperature-stabilized instruments used for in-the-field experiments, where the radiant power of the site changes continuously with the sun tilt. This paper describes the effect of ambient temperature on a nontemperature-stabilized linear photodiode array spectrometer over the temperature range from 5 deg. C to 40 deg. C. The nonlinearity effects on both signal amplification and different levels of radiant power have also been studied and are presented in this paper.

Salim, Saber G. R.; Fox, Nigel P.; Theocharous, Evangelos; Sun, Tong; Grattan, Kenneth T. V.

2011-02-20T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

The Wide Angular-Range Chopper Spectrometer at SNS | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

The Wide Angular-Range Chopper Spectrometer at SNS The Wide Angular-Range Chopper Spectrometer at SNS and Doug Abernathy at ARCS Materials researcher Judy Pang and instrument scientist Doug Abernathy at ARCS. ARCS is optimized to provide a high neutron flux at the sample and a large solid angle of detector coverage. This spectrometer is capable of selecting incident energies over the full energy spectrum of neutrons, making it useful for studies of excitations from a few to several hundred milli-electron volts. An elliptically shaped supermirror guide in the incident flight path boosts the performance at the lower end of this range. The sample and detector vacuum chambers provide a window-free final flight path and incorporate a large gate valve to allow rapid sample changeout. A T0 neutron chopper not only blocks the prompt radiation from the source

342

The tension of cosmological magnetic fields as a contribution to dark energy  

E-Print Network (OSTI)

We propose that cosmological magnetic fields generated in regions of finite spatial dimensions may manifest themselves in the global dynamics of the Universe as `dark energy'. We test our model in the context of spatially flat cosmological models by assuming that the Universe contains non-relativistic matter $\\rho_m\\propto \\alpha^{-3}$, dark energy $\\rho_{Q}\\propto \\alpha^{-3(1+w)}$, and an extra fluid with $\\rho_{B} \\propto \\alpha^{n-3}$ that corresponds to the magnetic field. We place constraints on the main cosmological parameters of our model by combining the recent supernovae type Ia data and the differential ages of passively evolving galaxies. In particular, we find that the model which best reproduces the observational data when $\\Omega_m=0.26$ is one with $\\Omega_{B}\\simeq 0.03$, $n\\simeq 7.68$, $\\Omega_{Q}\\simeq 0.71$ and $w\\simeq -0.8$.

Ioannis Contopoulos; Spyros Basilakos

2007-05-14T23:59:59.000Z

343

Induction, helicity, and alpha effect in a toroidal screw flow of liquid gallium  

SciTech Connect

We investigate experimentally induction mechanisms in a screw flow of gallium in a toroidal channel. The flow is nonstationary and operated in a spin-down regime: the channel (and fluid) are initially set into solid body rotation; as the channel is stopped the fluid is set into strong helical motion by diverters located inside the channel. In this study, we put a particular emphasis on the induction generated by these helical motions, which are expected to develop over the entire range of turbulent scales. We apply an external magnetic field either perpendicular to the channel axis parallel to it. At large scales the nonlinear induction mechanisms are associated with the Parker stretch and twist effect and with the expulsion due to overall rotation. Induction mechanisms can also originate in the small scale helicity as in the alpha induction effect of mean-field magnetohydrodynamics. Our measurements yield an upper bound for the alpha coefficient, significantly lower than estimates based on dimensional analysis. We discuss the consequences of our observations for the engineering of homogeneous dynamos in the laboratory.

Stepanov, R.; Denisov, S.; Noskov, V. [Institute of Continuous Media MechanicsKorolyov 1, 614061 Perm (Russian Federation); Volk, R.; Frick, P.; Pinton, J.-F. [Laboratoire de Physique de l'Ecole Normale Superieur de Lyon, CNRS UMR5672, 46 allee d'Italie, 69007 Lyon (France)

2006-04-15T23:59:59.000Z

344

Methods of Using Alpha Channeling Together with Transformer Recharging |  

NLE Websites -- All DOE Office Websites (Extended Search)

Methods of Using Alpha Channeling Together with Transformer Recharging Methods of Using Alpha Channeling Together with Transformer Recharging A tokamak current can be sustained using rf waves for transformer recharging at low density and high-Z with high efficiency if the resistivity is kept high enough during the radio frequency recharging stage. At the same time, operation in the hot ion mode via alpha channeling increases the effective fusion reactivity. The two separate inventions can be made to work synergistically. Specifically, by operating the tokamak in a low-density recharge phase, the lower hybrid wave penetrates the plasma more effectively. High reactivity is obtained by operation in the hot ion mode through the alpha channeling technique. Then, by using a high temperature relaxation stage, not only is the plasma current sustained

345

City of Alpha, Minnesota (Utility Company) | Open Energy Information  

Open Energy Info (EERE)

Alpha, Minnesota (Utility Company) Alpha, Minnesota (Utility Company) Jump to: navigation, search Name City of Alpha Place Minnesota Utility Id 266 Utility Location Yes Ownership M NERC Location MRO Activity Bundled Services Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Commercial Commercial Residential Residential Average Rates Residential: $0.0758/kWh Commercial: $0.0957/kWh References ↑ "EIA Form EIA-861 Final Data File for 2010 - File1_a" Retrieved from "http://en.openei.org/w/index.php?title=City_of_Alpha,_Minnesota_(Utility_Company)&oldid=409261" Categories:

346

The alpha-particle induced bystander effect for sister chromatid...  

NLE Websites -- All DOE Office Websites (Extended Search)

agents than typical FA cells. We studied the effects of low-dose alpha-particle irradiation-induced bystander effects in KO40 and control CHO cell lines. Cultures of G0...

347

Alpha-beta coordination method for collective search - Energy ...  

An agent in the alpha role is motivated to improve its status by exploring new regions of the search space. ... Solar Photovoltaic; Solar ... by the U.S. Department ...

348

Baroclinic Instabilities of the Two-Layer Quasigeostrophic Alpha Model  

Science Conference Proceedings (OSTI)

The class of alpha models for turbulence may be derived by applying Lagrangian averaging to the exact fluid equations and then making a closure approximation based on Taylor’s hypothesis of frozen-in fluctuations. This derivation provides a ...

Darryl D. Holm; Beth A. Wingate

2005-07-01T23:59:59.000Z

349

Energetics of [alpha]-helix formation in peptides and proteins  

E-Print Network (OSTI)

This thesis focuses on the energetics of !-helix formation in peptides and proteins. The [alpha]-helix is the most prevalent type of secondary structure found in proteins, and has arguably dominated our thinking about ...

Schubert, Christian Reinhold

2009-01-01T23:59:59.000Z

350

Fermi Surface of Uranium at Ambient Pressure Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network (OSTI)

Fermi Surface of ­Uranium at Ambient Pressure Gregory S. Boebinger, National High Magnetic Field Laboratory DMR-Award 0654118 DC Field Facility User Program The fermi surface of ­Uranium has been measured surface of alpha-uranium at ambient pressure, Phys. Rev. B Rapid Commun., 80, 241101 (2009). B//c-axis B

Weston, Ken

351

Labeled ALPHA4BETA2 ligands and methods therefor  

DOE Patents (OSTI)

Contemplated compositions and methods are employed to bind in vitro and in vivo to an .alpha.4.beta.2 nicotinic acetylcholine receptor in a highly selective manner. Where such compounds are labeled, compositions and methods employing such compounds can be used for PET and SPECT analysis. Alternatively, and/or additionally contemplated compounds can be used as antagonists, partial agonists or agonists in the treatment of diseases or conditions associated with .alpha.4.beta..beta.2 dysfunction.

Mukherjee, Jogeshwar; Pichika, Ramaiah; Potkin, Steven; Leslie, Frances; Chattopadhyay, Sankha

2013-02-19T23:59:59.000Z

352

Applying Alpha-Channeling to Mirror Machines  

SciTech Connect

The ?-channeling effect entails the use of radio-frequency waves to expel and cool high-energetic ?- particles born in a fusion reactor; the device reactivity can then be increased even further by redirecting the extracted energy to fuel ions. Originally proposed for tokamaks, this technique has also been shown to benefi t open-ended fusion devices. Here, the fundamental theory and practical aspects of ?- channeling in mirror machines are reviewed, including the influence of magnetic field inhomogeneity and the effect of a finite wave region on the ?-channeling mechanism. For practical implementation of the ? -channeling effect in mirror geometry, suitable contained weakly-damped modes are identifi ed. In addition, the parameter space of candidate waves for implementing the ? -channeling effect can be signi cantly extended through the introduction of a suitable minority ion species that has the catalytic effect of moderating the transfer of power from the ?-channeling wave to the fuel ions.

A.I. Zhmoginov and N.J. Fisch

2012-03-16T23:59:59.000Z

353

MAGNETIC TOPOLOGY OF BUBBLES IN QUIESCENT PROMINENCES  

Science Conference Proceedings (OSTI)

We study a polar-crown prominence with a bubble and its plume observed in several coronal filters by the SDO/AIA and in H{alpha} by the MSDP spectrograph in Bialkow (Poland) to address the following questions: what is the brightness of prominence bubbles in EUV with respect to the corona outside of the prominence and the prominence coronal cavity? What is the geometry and topology of the magnetic field in the bubble? What is the nature of the vertical threads seen within prominences? We find that the brightness of the bubble and plume is lower than the brightness of the corona outside of the prominence, and is similar to that of the coronal cavity. We constructed linear force-free models of prominences with bubbles, where the flux rope is perturbed by inclusion of parasitic bipoles. The arcade field lines of the bipole create the bubble, which is thus devoid of magnetic dips. Shearing the bipole or adding a second one can lead to cusp-shaped prominences with bubbles similar to the observed ones. The bubbles have complex magnetic topology, with a pair of coronal magnetic null points linked by a separator outlining the boundary between the bubble and the prominence body. We conjecture that plume formation involves magnetic reconnection at the separator. Depending on the viewing angle, the prominence can appear either anvil-shaped with predominantly horizontal structures, or cusp-shaped with predominantly vertical structuring. The latter is an artifact of the alignment of magnetic dips with respect to the prominence axis and the line of sight.

Dudik, J. [DAPEM, Faculty of Mathematics Physics and Computer Science, Comenius University, Mlynska Dolina F2, 84248 Bratislava (Slovakia); Aulanier, G.; Schmieder, B. [Observatoire de Paris, LESIA, UMR 8109 (CNRS), F-92195 Meudon Principal Cedex (France); Zapior, M. [Astronomical Institute, University of Wroclaw, Kopernika 11, 51622 Wroclaw (Poland); Heinzel, P., E-mail: dudik@fmph.uniba.sk [Astronomical Institute of the Academy of Sciences of the Czech Republic, Fricova 298, 25165 Ondrejov (Czech Republic)

2012-12-10T23:59:59.000Z

354

H/sub. cap alpha. / studies on TFTR  

DOE Green Energy (OSTI)

H/sub ..cap alpha../ emission is a useful indicator of hydrogen ionization since the energy required to excite hydrogen to the n = 3 level is approximately the same as to ionize the hydrogen atom. Other aspects of recycling, such as plasma scrape-off parameters, wall particle fluxes, and wall retention rates can be inferred from spatial distributions of H/sub ..cap alpha../ emission. There are two H/sub ..cap alpha../ diagnostics on TFTF observing the inner limiter: a relatively calibrated wide-angle TV camera, and the absolutely calibrated HAIFA diagnostic, both viewing the inner limiter. H/sub ..cap alpha../ observations by these instruments have been analyzed using the DEGAS neutral transport code. The core recycling rate, and ion and neutral particle limiter fluxes, have been deduced from the calculations. The results are very sensitive to the ion flux distribution, and therefore also provide information on the plasma scrape-off conditions. A survey was made of over 500 TFTR discharges. H/sub ..cap alpha../ emission appears to increase in proportion to /bar n//sub e//sup 2/. The ratio of core ionization to average H/sub ..cap alpha../ emission was calculated to be roughly constant over a large range of discharges. 9 refs., 4 figs., 1 tab.

Heifetz, D.B.; Ehrhardt, A.B.; Ramsey, A.T.; Dylla, H.F.; Budny, R.; McNeill, D.; Medley, S.; Ulrickson, M.

1988-08-01T23:59:59.000Z

355

First Results from the Large Area Lyman Alpha Survey  

E-Print Network (OSTI)

We report on a new survey for z=4.5 Lyman alpha sources, the Large Area Lyman Alpha (LALA) survey. Our survey achieves an unprecedented combination of volume and sensitivity by using narrow-band filters on the new 8192x8192 pixel CCD Mosaic Camera at the 4 meter Mayall telescope of Kitt Peak National Observatory. Well-detected sources with flux and equivalent width matching known high redshift Lyman alpha galaxies (i.e., observed equivalent width above 80 Angstroms and line+continuum flux between 2.6e-17 and 5.2e-17 erg/cm^2/sec in an 80 Angstrom filter) have an observed surface density corresponding to 11000 +- 700 per square degree per unit redshift at z=4.5. Spatial variation in this surface density is apparent on comparison between counts in 6561 and 6730 Angstrom filters. Early spectroscopic followup results from the Keck telescope included three sources meeting our criteria for good Lyman alpha candidates. Of these, one is confirmed as a z=4.52 source, while another remains consistent with either z=4.55 or z=0.81. We infer that 30 to 50% of our good candidates are bona fide Lyman alpha emitters, implying a net density of about 4000 Lyman alpha galaxies per square degree per unit redshift.

James E. Rhoads; Sangeeta Malhotra; Arjun Dey; Daniel Stern; Hyron Spinrad; Buell Jannuzi

2000-03-31T23:59:59.000Z

356

Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets  

SciTech Connect

Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.

None

2010-10-01T23:59:59.000Z

357

HTS Magnet Program | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

HTS Magnet Program HTS Magnet Program High Temperature Superconductors (HTS) have the potential to revolutionize the field of superconducting magnets for particle accelerators, energy storage and medical applications. This is because of the fact that as compared to the conventional Low Temperature Superconductors (LTS), the critical current density (Jc ) of HTS falls slowly both: as a function of increasing field, and as a function of increasing temperature These unique properties can be utilized to design and build: HTS magnets that produce very high fields (20 - 50 T) HTS magnets that operate at elevated temperatures (20 - 77 K) This is a significant step forward over the convention LTS magnets which generally operate at a temperature of ~4 K and with field usually limited

358

RAYLEIGH-TAYLOR STRENGTH EXPERIMENTS OF THE PRESSURE-INDUCED alpha->epsilon->alpha' PHASE TRANSITION IN IRON  

SciTech Connect

We present here the first dynamic Rayleigh-Taylor (RT) strength measurement of a material undergoing solid-solid phase transition. Iron is quasi-isentropically driven across the pressure-induced bcc ({alpha}-Fe) {yields} hcp ({var_epsilon}-Fe) phase transition and the dynamic strength of the {alpha}, {var_epsilon} and reverted {alpha}{prime} phases have been determined via proton radiography of the resulting Rayleigh-Taylor unstable interface between the iron target and high-explosive products. Simultaneous velocimetry measurements of the iron free surface yield the phase transition dynamics and, in conjunction with detailed hydrodynamic simulations, allow for determination of the strength of the distinct phases of iron. Forward analysis of the experiment via hydrodynamic simulations reveals significant strength enhancement of the dynamically-generated {var_epsilon}-Fe and reverted {alpha}{prime}-Fe, comparable in magnitude to the strength of austenitic stainless steels.

Belof, J L; Cavallo, R M; Olson, R T; King, R S; Gray, G T; Holtkamp, D B; Chen, S R; Rudd, R E; Barton, N R; Arsenlis, A; Remington, B A; Park, H; Prisbrey, S T; Vitello, P A; Bazan, G; Mikaelian, K O; Comley, A J; Maddox, B R; May, M J

2011-08-10T23:59:59.000Z

359

Samuel C.C. Ting, the J/psi Particle (Charm), and the Alpha Magnetic...  

Office of Scientific and Technical Information (OSTI)

University where he became interested in the physics of electron-positron pair production. ... In the spring of 1972, Ting, then on the faculty at the Massachusetts Institute...

360

alpha_s and the tau hadronic width: fixed-order, contour-improved and higher-order perturbation theory  

E-Print Network (OSTI)

The determination of $\\alpha_s$ from hadronic $\\tau$ decays is revisited, with a special emphasis on the question of higher-order perturbative corrections and different possibilities of resumming the perturbative series with the renormalisation group: fixed-order (FOPT) vs. contour-improved perturbation theory (CIPT). The difference between these approaches has evolved into a systematic effect that does not go away as higher orders in the perturbative expansion are added. We attempt to clarify under which circumstances one or the other approach provides a better approximation to the true result. To this end, we propose to describe the Adler function series by a model that includes the exactly known coefficients and theoretical constraints on the large-order behaviour originating from the operator product expansion and the renormalisation group. Within this framework we find that while CIPT is unable to account for the fully resummed series, FOPT smoothly approaches the Borel sum, before the expected divergent behaviour sets in at even higher orders. Employing FOPT up to the fifth order to determine $\\alpha_s$ in the $\\MSb$ scheme, we obtain $\\alpha_s(M_\\tau)=0.320 {}^{+0.012}_{-0.007}$, corresponding to $\\alpha_s(M_Z) = 0.1185 {}^{+0.0014}_{-0.0009}$. Improving this result by including yet higher orders from our model yields $\\alpha_s(M_\\tau)=0.316 \\pm 0.006$, which after evolution leads to $\\alpha_s(M_Z) = 0.1180 \\pm 0.0008$. Our results are lower than previous values obtained from $\\tau$ decays.

Martin Beneke; Matthias Jamin

2008-06-19T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Bucking Coil Implementation on PMT for Active Cancelling of Magnetic Field  

SciTech Connect

Aerogel and water Cerenkov detectors were employed to tag kaons for a lambda hypernuclear spectroscopic experiment which used the (e,e'K{sup +}) reaction in experimental Hall C at Jefferson Lab (JLab E05-115). Fringe fields from the kaon spectrometer magnet yielded ~5 Gauss at the photomultiplier tubes (PMT) for these detectors which could not be easily shielded. As this field results in a lowered kaon detection efficiency, we implemented a bucking coil on each photomultiplier tubes to actively cancel this magnetic field, thus maximizing kaon detection efficiency.

Gogami, T; Asaturyan, A; Bono, J; Baturin, P; Chen, C; Chiba, A; Chiga, N; Fujii, Y; Hashimoto, O; Kawama, D; Maruta, T; Maxwell, V; Mkrtchyan, A; Nagao, S; Nakamura, S N; Reinhold, J; Shichijo, A; Tang, L; Taniya, N; Wood, S A; Ye, Z

2013-11-01T23:59:59.000Z

362

Recovering the Line-Of-Sight Magnetic Field in the Chromosphere from Ca II IR Spectra  

E-Print Network (OSTI)

We propose a method to derive the line-of-sight magnetic flux density from measurements in the chromospheric Ca II IR line at 854.2 nm. The method combines two well-understood techniques, the center-of-gravity and bisector methods, in a single hybrid technique. The technique is tested with magneto-static simulations of a flux tube. We apply the method to observations with the Interferometric Bidimensional Spectrometer (IBIS) installed at the Dunn Solar Telescope of the NSO/SP to investigate the morphology of the lower chromosphere, with focus on the chromospheric counterparts to the underlying photospheric magnetic flux elements.

Wöger, F; Uitenbroek, H; Rimmele, T

2009-01-01T23:59:59.000Z

363

Nuclear magnetic resonance experiments with dc SQUID amplifiers  

Science Conference Proceedings (OSTI)

The development and fabrication of dc SQUIDs (Superconducting QUantum Interference Devices) with Nb/Al{sub 2}O{sub 3}/Nb Josephson junctions is described. A theory of the dc SQUID as a radio-frequency amplifier is presented, with an optimization strategy that accounts for the loading and noise contributions of the postamplifier and maximizes the signal-to-noise ratio of the total system. The high sensitivity of the dc SQUID is extended to high field NMR. A dc SQUID is used as a tuned radio-frequency amplifier to detect pulsed nuclear magnetic resonance at 32 MHz from a metal film in a 3.5 Tesla static field. A total system noise temperature of 11 K has been achieved, at a bath temperature of 4.2 K. The minimum number of nuclear Bohr magnetons observable from a free precession signal after a single pulse is about 2 {times} 10{sup 17} in a bandwidth of 25 kHz. In a separate experiment, a dc SQUID is used as a rf amplifier in a NQR experiment to observe a new resonance response mechanism. The net electric polarization of a NaClO{sub 3} crystal due to the precessing electric quadrupole moments of the Cl nuclei is detected at 30 MHz. The sensitivity of NMR and NQR spectrometers using dc SQUID amplifiers is compared to the sensitivity of spectrometers using conventional rf amplifiers. A SQUID-based spectrometer has a voltage sensitivity which is comparable to the best achieved by a FET-based spectrometer, at these temperatures and operating frequencies.

Heaney, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics Lawrence Berkeley Lab., CA (USA))

1990-11-01T23:59:59.000Z

364

Chemical Ionization Mass Spectrometer (CIMS) Shanhu Lee, Kent State University (http://www.personal.kent.edu/~slee19/)  

E-Print Network (OSTI)

Chemical Ionization Mass Spectrometer (CIMS) Shanhu Lee, Kent State University (http ionization mass spectrometry (PTR-CIMS). A typical CIMS instrument can be constructed from an ion source, an ion molecular reactor, and a quadrupole mass spectrometer. Shown below is schematic diagram of a CIMS

Lee, Shan-Hu

365

A High-Speed FPGA-Based Lossless Data Compression Design for the X-ray Spectrometer Solar Energy Spectra  

Science Conference Proceedings (OSTI)

In order to meet the real-time compression requirements effectively for the solar energy spectrum data of the X-ray spectrometer used as a key payload of Chang'E Mission, the design and implementation of the bit wise OR algorithm based on FPGA is presented ... Keywords: data compression, X-ray spectrometer, bitwise OR algorithm, FPGA

RuiMin Ma; HuanYu Wang

2011-09-01T23:59:59.000Z

366

Tamper resistant magnetic stripes  

DOE Patents (OSTI)

This invention relates to a magnetic stripe comprising a medium in which magnetized particles are suspended and in which the encoded information is recorded by actual physical rotation or alignment of the previously magnetized particles within the flux reversals of the stripe which are 180.degree. opposed in their magnetic polarity. The magnetized particles are suspended in a medium which is solid, or physically rigid, at ambient temperatures but which at moderately elevated temperatures, such as 40.degree. C., is thinable to a viscosity permissive of rotation of the particles therein under applications of moderate external magnetic field strengths within acceptable time limits.

Naylor, Richard Brian (Albuquerque, NM); Sharp, Donald J. (Albuquerque, NM)

1999-01-01T23:59:59.000Z

367

Influence of primordial magnetic fields on 21 cm emission  

E-Print Network (OSTI)

Magnetic fields in the early universe can significantly alter the thermal evolution and the ionization history during the dark ages. This is reflected in the 21 cm line of atomic hydrogen, which is coupled to the gas temperature through collisions at high redshifts, and through the Wouthuysen-Field effect at low redshifts. We present a semi-analytic model for star formation and the build-up of a Lyman alpha background in the presence of magnetic fields, and calculate the evolution of the mean 21 cm brightness temperature and its frequency gradient as a function of redshift. We further discuss the evolution of linear fluctuations in temperature and ionization in the presence of magnetic fields and calculate the effect on the 21 cm power spectrum. At high redshifts, the signal is increased compared to the non-magnetic case due to the additional heat input into the IGM from ambipolar diffusion and the decay of MHD turbulence. At lower redshifts, the formation of luminous objects and the build-up of a Lyman alpha...

Schleicher, Dominik R G; Klessen, Ralf S

2008-01-01T23:59:59.000Z

368

High-resolution bent-crystal spectrometer for the ultra-soft x-ray region  

SciTech Connect

A multichannel vacuum Brag-crystal spectrometer has been developed for high-resolution measurements of the line emission from tokamak plasmas in the wavelength region between 4 and 25 /angstrom/. The spectrometer employs a bent crystal in Johann geometry and a microchannel-plate intensified photodiode array. The instrument is capable of measuring high-resolution spectra (lambda/..delta..lambda approx. 3000) with fast time resolution (4 msec per spectrum) and good spatial resolution (3 cm). The spectral bandwidth is ..delta..lambda/lambda/sub 0/ = 8/angstrom/. A simple tilt mechanism allows access to different wavelength intervals. In order to illustrate the utility of the new spectrometer, time- and space-resolved measurements of the n = 3 to n = 2 spectrum of selenium from the Princeton Large Torus tokamak plasmas are presented. The data are used to determine the plasma transport parameters and to infer the radial distribution of fluorinelike, neonlike, and sodiumlike ions of selenium in the plasma. The new ultra-soft x-ray spectrometer has thus enabled us to demonstrate the utility of high-resolution L-shell spectroscopy of neonlike ions as a fusion diagnostic. 43 refs., 23 figs.

Beiersdorfer, P.; von Goeler, S.; Bitter, M.; Hill, K.W.; Hulse, R.A.; Walling, R.S.

1988-10-01T23:59:59.000Z

369

Sensitivity Upgrades to the Idaho Accelerator Center Neutron Time of Flight Spectrometer  

Science Conference Proceedings (OSTI)

Past experiments have shown that discrimination between between fissionable and non?fissionable materials is possible using an interrogation technique that monitors for high energy prompt fission neutrons. Several recent upgrades have been made to the neutron time of flight spectrometer at the Idaho Accelerator Center with the intent of increasing neutron detection sensitivity

S. J. Thompson; M. T. Kinlaw; J. F. Harmon; D. P. Wells; A. W. Hunt

2007-01-01T23:59:59.000Z

370

Gas chromatograph-mass spectrometer (GC/MS) system for quantitative analysis of reactive chemical compounds  

DOE Patents (OSTI)

Described is a new gas chromatograph-mass spectrometer (GC/MS) system and method for quantitative analysis of reactive chemical compounds. All components of such a GC/MS system external to the oven of the gas chromatograph are programmably temperature controlled to operate at a volatilization temperature specific to the compound(s) sought to be separated and measured.

Grindstaff, Quirinus G. (Oak Ridge, TN)

1992-01-01T23:59:59.000Z

371

High-resolution Bent-crystal Spectrometer for the Ultra-soft X-ray Region  

DOE R&D Accomplishments (OSTI)

A multichannel vacuum Brag-crystal spectrometer has been developed for high-resolution measurements of the line emission from tokamak plasmas in the wavelength region between 4 and 25 angstrom. The spectrometer employs a bent crystal in Johann geometry and a microchannel-plate intensified photodiode array. The instrument is capable of measuring high-resolution spectra (lambda/..delta..lambda approx. 3000) with fast time resolution (4 msec per spectrum) and good spatial resolution (3 cm). The spectral bandwidth is ..delta..lambda/lambda{sub 0} = 8 angstrom. A simple tilt mechanism allows access to different wavelength intervals. In order to illustrate the utility of the new spectrometer, time- and space-resolved measurements of the n = 3 to n = 2 spectrum of selenium from the Princeton Large Torus tokamak plasmas are presented. The data are used to determine the plasma transport parameters and to infer the radial distribution of fluorinelike, neonlike, and sodiumlike ions of selenium in the plasma. The new ultra-soft x-ray spectrometer has thus enabled us to demonstrate the utility of high-resolution L-shell spectroscopy of neonlike ions as a fusion diagnostic.

Beiersdorfer, P.; von Goeler, S.; Bitter, M.; Hill, K. W.; Hulse, R. A.; Walling, R. S.

1988-10-00T23:59:59.000Z

372

Gamma-ray energies for calibration of Ge(Li) spectrometers  

SciTech Connect

Gamma-ray energies are compared for bent-crystal measurements, Ge(Li) measurements, and other measurements. 150 gamma-ray energies below 3450 keV from 35 isotopes are being calibrated for calibration of Ge(Li) spectrometers. (WHK)

Helmer, R.G.; Greenwood, R.C.; Gehrke, R.J.

1975-01-01T23:59:59.000Z

373

An AOTF-LDTOF spectrometer suite for in situ organic detection and characterization  

Science Conference Proceedings (OSTI)

We discuss the development of a miniature near-infrared point spectrometer, operating in the 1.7 -- 4 mm region, based on acousto-optic tunable filter (AOTF) technology. This instrument may be used to screen and corroborate analyses of samples containing ...

Nancy J. Chanover; David A. Glenar; David G. Voelz; Xifeng Xiao; Rula Tawalbeh; Penelope J. Boston; William B. Brinckerhoff; Paul R. Mahaffy; Stephanie Getty; Inge ten Kate; Amy McAdam

2011-03-01T23:59:59.000Z

374

Atmospheric Water Content over the Tropical Pacific Derived from the Nimbus-6 Scanning Microwave Spectrometer  

Science Conference Proceedings (OSTI)

The scanning microwave spectrometer (SCAMS) aboard Nimbus-6 contains a 22.23 GHz water vapor channel and 31.65 GHz window channel for deriving integrated water vapor (precipitable water) and cloud liquid water through a column over the oceans. ...

N. C. Grody; A. Gruber; W. C. Shen

1980-08-01T23:59:59.000Z

375

Lensless Imaging of Magnetic Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine....

376

The Discovery of Broad P Cygni X-ray Lines from Circinus X-1 with the Chandra High Energy Transmission Grating Spectrometer  

E-Print Network (OSTI)

We present the first grating-resolution X-ray spectra of the X-ray binary Cir X-1, obtained with the High Energy Transmission Grating Spectrometer on Chandra. These reveal a rich set of lines from H-like and/or He-like Ne, Mg, Si, S and Fe detected with a high signal-to-noise ratio. The lines are broad (+/- 2000 km/s) and show P Cygni profiles. The absorption components of the lines extend to low velocity, and they have about the same widths and strengths as the corresponding emission components. The widths of the X-ray P Cygni lines are comparable to that of the broad component of the strong, asymmetric H-alpha line from Cir X-1, suggesting that the two phenomena may be related. We discuss outflow models and propose that the P Cygni profiles may arise in the moderate temperature (5 x 10^6 K) region of the wind from an X-ray heated accretion disk. This basic picture strengthens the idea that the accretion disk in Cir X-1 is viewed in a relatively edge-on manner, and it suggests that Cir X-1 is the X-ray binary analog of a Broad Absorption Line quasar.

W. N. Brandt; N. S. Schulz

2000-07-26T23:59:59.000Z

377

LANSCE | Lujan Center | Thrust Area | Local Structure, Magnetism, and  

NLE Websites -- All DOE Office Websites (Extended Search)

User Instruments User Instruments Reflectometers Asterix SPEAR Powder Diffractometers HIPD HIPPO NPDF Engineering Diffraction SMARTS Chemical Spectroscopy FDS Small Angle Scattering LQD Protein Crystallography PCS Inelastic Neutron Spectrometer Pharos Single Crystal Diffractometer SCD Contacts Lujan Center Leader Mark Bourke 505.667.6069 Deputy Leader (Interim) Anna Llobet 505.665.1367 Experimental Area Manager) Charles Kelsey 505.665.5579 Experiment Coordinator Leilani Conradson 505.665.9505 User Office Administrator Lisa Padilla 505.667.5649 Administrative Assistant Melissa Martinez 505.665.0391 Thrust Area Local Structure, Magnetism, and Nanomaterials The Lujan Neutron Scattering Center encompasses a set of powder diffractometers, instrument scientist specialists, and sample environments (pressure, temperature, and magnetic field) equipped to address challenges

378

Remote Energetic Neutral Atom Imaging of Electric Potential Over a Lunar Magnetic Anomaly  

E-Print Network (OSTI)

The formation of electric potential over lunar magnetized regions is essential for understanding fundamental lunar science, for understanding the lunar environment, and for planning human exploration on the Moon. A large positive electric potential was predicted and detected from single point measurements. Here, we demonstrate a remote imaging technique of electric potential mapping at the lunar surface, making use of a new concept involving hydrogen neutral atoms derived from solar wind. We apply the technique to a lunar magnetized region using an existing dataset of the neutral atom energy spectrometer SARA/CENA on Chandrayaan-1. Electrostatic potential larger than +135 V inside the Gerasimovic anomaly is confirmed. This structure is found spreading all over the magnetized region. The widely spread electric potential can influence the local plasma and dust environment near the magnetic anomaly.

Futaana, Y; Wieser, M; Lue, C; Wurz, P; Vorburger, A; Bhardwaj, A; Asamura, K; 10.1002/grl.50135

2013-01-01T23:59:59.000Z

379

LHC Magnet Program | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnet Program Magnet Program The Superconducting Magnet Division is building a number of dipole magnets for the Large Hadron Collider (LHC), which is now under construction at CERN in Geneva, Switzerland. Scheduled to begin operation in 2007, this machine will collide beams of protons with the unprecedented energy of 7 TeV per beam to explore the nature of matter at its most basic level (RHIC can collide beams of protons with energies of 0.25 TeV, but is mostly used to collide heavy ions with energies of 0.1 TeV per nucleon). The magnets are being built as part of the US program, recommended by the High Energy Physics Advisory Panel (HEPAP) and approved by Congress, to contribute to the construction and, later, use of that frontier machine by the US high energy physics community. Fermi National Accelerator Laboratory (FNAL) and

380

NONLINEAR FORCE-FREE MODELING OF MAGNETIC FIELDS IN A SOLAR FILAMENT  

SciTech Connect

We present a striking filament pattern in the nonlinear force-free (NLFF) chromospheric magnetic field of the active region NOAA 10956. The NLFF chromospheric field is extrapolated from the Hinode high-resolution photospheric vector magnetogram using the weighted optimization method. The modeled structure is characterized by a highly sheared field with strong horizontal magnetic components and has a virtually identical shape and location as the filament seen in H{alpha}. The modeled field strength agrees with the recent He I 10830 A observations by Kuckein et al.. The unequivocal resemblance between the NLFF extrapolation and the H{alpha} observation not only demonstrates the ability of the NLFF field to reproduce chromospheric features, but also provides a valuable diagnostic tool for the filament magnetic fields.

Jing Ju; Yuan Yuan; Xu Yan; Liu Rui; Wang Haimin [Space Weather Research Laboratory, New Jersey Institute of Technology, Newark, NJ 07102 (United States); Wiegelmann, Thomas, E-mail: ju.jing@njit.ed, E-mail: yy46@njit.ed, E-mail: yx2@njit.ed, E-mail: rui.liu@njit.ed, E-mail: haimin@flare.njit.ed, E-mail: wiegelmann@linmpi.mpg.d [Max Planck Institut fuer Sonnensystemforschung (MPS), Max-Planck-Strasse 2, 37191 Katlenburg-Lindau (Germany)

2010-08-10T23:59:59.000Z

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381

Active magnetic regenerator  

SciTech Connect

The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

Barclay, John A. (Los Alamos, NM); Steyert, William A. (Los Alamos, NM)

1982-01-01T23:59:59.000Z

382

ALS superbend magnet performance  

E-Print Network (OSTI)

ALS Superbend Magnet Performance S. Marks, J. Zbasnik, W.the Advanced Light Source (ALS), with the fourth magnet as ahe Advanced Light Source (ALS) at the Lawrence Berkeley

2001-01-01T23:59:59.000Z

383

Alpha-beta coordination method for collective search  

DOE Patents (OSTI)

The present invention comprises a decentralized coordination strategy called alpha-beta coordination. The alpha-beta coordination strategy is a family of collective search methods that allow teams of communicating agents to implicitly coordinate their search activities through a division of labor based on self-selected roles and self-determined status. An agent can play one of two complementary roles. An agent in the alpha role is motivated to improve its status by exploring new regions of the search space. An agent in the beta role is also motivated to improve its status, but is conservative and tends to remain aggregated with other agents until alpha agents have clearly identified and communicated better regions of the search space. An agent can select its role dynamically based on its current status value relative to the status values of neighboring team members. Status can be determined by a function of the agent's sensor readings, and can generally be a measurement of source intensity at the agent's current location. An agent's decision cycle can comprise three sequential decision rules: (1) selection of a current role based on the evaluation of the current status data, (2) selection of a specific subset of the current data, and (3) determination of the next heading using the selected data. Variations of the decision rules produce different versions of alpha and beta behaviors that lead to different collective behavior properties.

Goldsmith, Steven Y. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

384

Transcriptional regulation of human retinoic acid receptor-alpha (RAR-{alpha}) by Wilms` tumour gene product  

SciTech Connect

The Wilms` tumor gene encodes a 47-49 kDa transcription factor expressed in kidney, gonads and mesothelium during embryogenesis. Inherited mutations of WT1 lead to aberrant urogenital development and Wilms` tumor, but the role of WT1 in development is not fully understood. Since the human RAR-{alpha} gene contains a potential WT1 binding site at its 5{prime} end, we studied the effect of WT1 co-transfection on expression of an RAR-{alpha} promoter/CAT reporter construct in COS cells. COS cells were plated at 5X10{sup 5} cells/dish in DMEM with 10% FBS and transfected by the Ca/PO4 method with an expression plasmid containing the full-length WT1 (-/-) cDNA under the control of the CMV promoter, plasmid containing the RAR-{alpha} promoter (-519 to +36)/CAT reporter and TK/growth hormone plasmid to control for efficiency of transfection. CAT/GH activity at 48 hours was inhibited by co-transfection with increasing amounts of WT1 (-/-); maximum inhibition = 5% of control. WT1 co-transfection did not affect expression of TKGH, nor of a CMV-CAT vector. Expression of WT1 protein in tranfected COS cells was demonstrated by Western blotting. Minimal inhibiton of RAR-{alpha}/CAT activity was seen when cells were co-transfected with vectors containing WT1 deletion mutants, alternate WT1 splicing variants, or WT1 (-/-) cDNA bearing a mutation identified in a patient with Drash syndrome. Gel shift assays indicated binding of WT1 to RAR-{alpha} cDNA but not to an RAR-{alpha} deletion mutant lacking the GCGGGGGGCG site. These observations suggest that WT1 may function to regulate RAR-{alpha} expression during normal development.

Goodyer, P.R.; Torban, E.; Dehbi, M. [and others

1994-09-01T23:59:59.000Z

385

Superconducting magnet of Aurora  

Science Conference Proceedings (OSTI)

The AURORAsuperconducting magnet system is composed of a cylindrical single?body magnet and a refrigeration system for superconducting coils. The magnet generates B z =1 T on the central orbit at the 150 MeV electron beam injection energy and B z =4.3 T at the 650 MeV storage energy. The diameter of the central orbit is 1 m. Iron poles and yokes are used for shielding the magnetic field

T. Takayama; SHI Accelerator Research Group

1989-01-01T23:59:59.000Z

386

Magnetic Materials Staff  

Science Conference Proceedings (OSTI)

... Materials Science and Engineering Division Staff Directory; MML Organization. Contact. Magnetic Materials Group Robert Shull, Group Leader. ...

2012-10-09T23:59:59.000Z

387

Minimum Magnetic Energy Theorem  

E-Print Network (OSTI)

The Thomson's Theorem states that static charge distributions in conductors show up at the conducting surfaces in an equipotential configuration, so that the electrostatic energy is a minimum. In this work we study an analogue statement for magnetic systems: in a given set of conductors, the stored magnetic field energy reaches the minimum value for superficial current distributions so that the magnetic vector potential is tangent to the conductors surfaces. This is the counterpart of Thomson's theorem for the magnetic field.

Fiolhais, M C N

2008-01-01T23:59:59.000Z

388

Magnetic Nanoparticle Metrology  

Science Conference Proceedings (OSTI)

... T2 relaxation times, hysteretic energy loss, etc ... Optimization of magnetic nanoparticle synthesis for ... competition between lattice energies and dipolar ...

2012-12-03T23:59:59.000Z

389

Irreversible magnetic switch  

DOE Patents (OSTI)

This invention is comprised of an irreversible magnetic switch containing a ferromagnetic amorphous metal having a predetermined crystallization temperature in its inductor magnetic path. With the incorporation of such material, the magnetic properties after cooling from a high temperature excursion above its crystallization temperature are only a fraction of the original value. The difference is used to provide a safety feature in the magnetic switch.

Karnowsky, M.M.; Yost, F.G.

1991-12-31T23:59:59.000Z

390

Magnetic nanohole superlattices  

DOE Patents (OSTI)

A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

Liu, Feng

2013-05-14T23:59:59.000Z

391

Tunable Magnetic Regenerator/Refrigerant  

Magnetic regenerators utilize the magnetocaloric effect--the ability of a magnetic field to reduce the magnetic part of a solid materials entropy, generating heat, and then removing the magnetic field, permitting the reduction of temperature with the ...

392

High-resolution measurements, line identification, and spectral modeling of K[alpha] transitions in Fe XVIII-XXV  

SciTech Connect

The iron K[alpha] emission spectrum covering the wavelength region from 1.840 to 1.940 [Angstrom] is analyzed. Measurements are made with a high-resolution Bragg crystal spectrometer on the Princeton Large Torus (PLT) tokamak for plasma conditions which closely resemble those of solar flares. A total of 40 features are identified consisting of either single or multiple lines from eight charge states in iron, Fe XVIII through Fe XXV, and their wavelengths are determined with an accuracy of 0.1--0.4 m[Angstrom]. Many of these features are identified for the first time. In the interpretation of our observations we rely on model calculations that determine the ionic species abundances from electron density and temperature profiles measured independently with non-spectroscopic techniques and that incorporate theoretical collisional excitation and dielectronic recombination rates resulting in the excitation of the 1s2s[sup r]2p[sup s] configurations. The model calculations also include the effect of diffusive ion transport. Good overall agreement between the model calculations and the observations is obtained, which gives us confidence in our line identifications and spectral modeling capabilities. The results are compared with earlier analyses of the K[alpha] emission from the Sun. While many similarities are found, a few differences arise from the somewhat higher electron density in tokamak plasmas (10[sup 13] cm[sup [minus]3]), which affects the fine-structure level populations of the ground states of the initial ion undergoing electron-impact excitation or dielectronic recombination. We also find that several spectral features are comprised of different transitions from those reported in earlier analyses of solar data.

Beiersdorfer, P.; Phillips, T. (Lawrence Livermore National Lab., CA (United States)); Jacobs, V.L. (Naval Research Lab., Washington, DC (United States). Condensed Matter and Radiation Sciences Div.); Hill, K.W.; Bitter, M.; von Goeler, S. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Kahn, S.M. (California Univ., Berkeley, CA (United States))

1992-11-01T23:59:59.000Z

393

High-resolution measurements, line identification, and spectral modeling of K{alpha} transitions in Fe XVIII-XXV  

Science Conference Proceedings (OSTI)

The iron K{alpha} emission spectrum covering the wavelength region from 1.840 to 1.940 {Angstrom} is analyzed. Measurements are made with a high-resolution Bragg crystal spectrometer on the Princeton Large Torus (PLT) tokamak for plasma conditions which closely resemble those of solar flares. A total of 40 features are identified consisting of either single or multiple lines from eight charge states in iron, Fe XVIII through Fe XXV, and their wavelengths are determined with an accuracy of 0.1--0.4 m{Angstrom}. Many of these features are identified for the first time. In the interpretation of our observations we rely on model calculations that determine the ionic species abundances from electron density and temperature profiles measured independently with non-spectroscopic techniques and that incorporate theoretical collisional excitation and dielectronic recombination rates resulting in the excitation of the 1s2s{sup r}2p{sup s} configurations. The model calculations also include the effect of diffusive ion transport. Good overall agreement between the model calculations and the observations is obtained, which gives us confidence in our line identifications and spectral modeling capabilities. The results are compared with earlier analyses of the K{alpha} emission from the Sun. While many similarities are found, a few differences arise from the somewhat higher electron density in tokamak plasmas (10{sup 13} cm{sup {minus}3}), which affects the fine-structure level populations of the ground states of the initial ion undergoing electron-impact excitation or dielectronic recombination. We also find that several spectral features are comprised of different transitions from those reported in earlier analyses of solar data.

Beiersdorfer, P.; Phillips, T. [Lawrence Livermore National Lab., CA (United States); Jacobs, V.L. [Naval Research Lab., Washington, DC (United States). Condensed Matter and Radiation Sciences Div.; Hill, K.W.; Bitter, M.; von Goeler, S. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Kahn, S.M. [California Univ., Berkeley, CA (United States)

1992-11-01T23:59:59.000Z

394

Isochronal Annealing Studies in Pu and Pu Alloys Using Magnetic Susceptibility  

Science Conference Proceedings (OSTI)

The isochronal annealing of the low temperature accumulated damage from the radioactive decay of plutonium in {alpha}-Pu, {delta}-Pu{sub 1-x}Ga{sub x} (x = 0.043) and {delta}-Pu{sub 1-x}Am{sub x} (x = 0.224) was characterized using magnetic susceptibility. In each specimen, thermal annealing, as tracked by magnetic susceptibility, only commenced when T > 33 K and the magnetic susceptibility changes due to defects were fully annealed at T not, vert, similar 300 K. The {alpha}-Pu magnetic susceptibility isochronal annealing data is similar to earlier measurements of resistivity characterized isochronal annealing. However, the {delta}-Pu{sub 1-x}Ga{sub x} (x = 0.043) magnetic susceptibility isochronal annealing data, when compared with similar resistivity data, indicates that for this alloy magnetic susceptibility studies are more sensitive to vacancies than to the interstitials accumulated at low temperatures. The Pu{sub 1-x}Am{sub x} (x = 0.224) alloy shows a remarkable change in properties, over a limited temperature range beginning where interstitial defects are first mobile, and characterized by an induced effective moment of order 1.1 {mu}{sub B}/Pu. This transient behavior may be evidence for a disorder driven low temperature phase transition, perhaps indicative of a compositional and structural proximity to a state possessing significant magnetic moments.

McCall, S. K. [Lawrence Livermore National Laboratory (LLNL); Fluss, M. J. [Lawrence Livermore National Laboratory (LLNL); Chung, B. W. [Lawrence Livermore National Laboratory (LLNL); McElfresh, M. W. [Lawrence Livermore National Laboratory (LLNL); Chapline, G.F. [Lawrence Livermore National Laboratory (LLNL); Jackson, D. D. [Lawrence Livermore National Laboratory (LLNL); Haire, Richard {Dick} G [ORNL

2007-01-01T23:59:59.000Z

395

The Wisconsin H-Alpha Mapper Northern Sky Survey  

E-Print Network (OSTI)

The Wisconsin H-Alpha Mapper (WHAM) has completed a survey in Balmer Alpha of the entire Northern sky above declination -30 deg. This survey provides the first calibrated, velocity-resolved map of the H-Alpha emission from the Galaxy. With one-degree spatial resolution, 12 km s^{-1} velocity resolution, and sensitivity to features as faint as 0.1 R (EM ~ 0.2 cm^{-6} pc), this survey provides the deepest maps of the ionized content of the Galaxy to date. In addition to probing the detailed kinematic structure of the Warm Ionized Medium and the vertical structure of the ionized content in spiral arms, initial results include the discovery of several faint, extended (d > 1\\deg) H II regions and the first map of the ionized component of an intermediate velocity cloud.

L. M. Haffner

2000-10-04T23:59:59.000Z

396

Apparatus for detecting alpha radiation in difficult access areas  

DOE Patents (OSTI)

An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure.

Steadman, Peter (Santa Fe, NM); MacArthur, Duncan W. (Los Alamos, NM)

1997-09-02T23:59:59.000Z

397

Magnetic damping for maglev  

DOE Green Energy (OSTI)

Magnetic damping is one of the important parameters to control the response and stability of maglev systems. An experimental study is presented to measure the magnetic damping using a direct method. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters on magnetic damping such as conductivity, gap, excitation frequency, and oscillation amplitude. The experimental technique is capable of measuring all magnetic damping coefficients, some of which can not be measured by an indirect method.

Chen, S.S.; Zhu, S.; Cai, Y.; Rote, D.M. [Argonne National Lab., IL (United States). Energy Technology Div.

1994-12-31T23:59:59.000Z

398

Magnetically attached sputter targets  

DOE Patents (OSTI)

An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

Makowiecki, D.M.; McKernan, M.A.

1994-02-15T23:59:59.000Z

399

Alpha low-level stored waste systems design study  

SciTech Connect

The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex`s Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT&E) requirements for each of the three concepts.

Feizollahi, F.; Teheranian, B. [Morrison Knudson Corp., San Francisco, CA (United States). Environmental Services Div.; Quapp, W.J. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

1992-08-01T23:59:59.000Z

400

Alpha low-level stored waste systems design study  

SciTech Connect

The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex's Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT E) requirements for each of the three concepts.

Feizollahi, F.; Teheranian, B. (Morrison Knudson Corp., San Francisco, CA (United States). Environmental Services Div.); Quapp, W.J. (EG and G Idaho, Inc., Idaho Falls, ID (United States))

1992-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

First-principles elastic properties of (alpha)-Pu  

SciTech Connect

Density-functional electronic structure calculations have been used to investigate the ambient pressure and low temperature elastic properties of the ground-state {alpha} phase of plutonium metal. The electronic structure and correlation effects are modeled within a fully relativistic anti-ferromagnetic treatment with a generalized gradient approximation for the electron exchange and correlation functionals. The 13 independent elastic constants, for the monoclinic {alpha}-Pu system, are calculated for the observed geometry. A comparison of the results with measured data from resonant ultrasound spectroscopy for a cast sample is made.

Soderlind, P; Klepeis, J E

2008-11-04T23:59:59.000Z

402

Humidity response of the Eberline model PAC-7 alpha instrument  

SciTech Connect

Response of the Eberline Model PAC-7 alpha instrument under varying relative humidity (RH) and temperature conditions was studied in an environmental chamber. Electric discharges resulting in spurious counts or in instrument paralysis occurred at 35 to 50% RH. Improvement in the RH level tolerated by the PAC-7 alpha instrument was obtained by conformal coating of the high-voltage region of the printed circuit (PC) board. Following this treatment, electric discharges occurred only at relatively high humidity levels and then as a result of high-voltage breakdown within the AC-24C probe rather than within the PC board.

McAtee, J.L.

1981-04-01T23:59:59.000Z

403

Some numerical reslts on best uniform polynomial approximation of {chi}{sup {alpha}} on [0,1  

Science Conference Proceedings (OSTI)

Let {alpha} be a positive number, and let E{sub n}(chi{sup {alpha}}; [0,1]) denote the error of best uniform approximation to {chi}{sup {alpha}}, by polynomials of degree at most n, on the interval [0,1]. The Russian mathematician S.N. Bernstein established the existence of a nonnegative constant {Beta}({alpha}) such that {Beta}({alpha}):= {sub n{yields}{infinity}lim(2n){sup 2{alpha}}E{sub n}({chi}{sup {alpha}};[0.1]). In addition, Bernstein showed that {Beta}{alpha} 0) and that {Gamma}(2{alpha}){vert_bar}sin({pi}{alpha}){vert_bar}/{pi} (1{minus}1/2{alpha}{minus}1) {1/2}), so that the asymptotic behavior of {Beta}({alpha}) is known when {alpha}{yields}{infinity}. Still, the problem of trying to determine {Beta}({alpha}) more precisely, for all {alpha} > 0, is intriguing. To this end, we have rigorously determined the numbers for thirteen values of {alpha}, where these numbers were calculated with a precision of at least 200 significant digits. For each of these thirteen values of {alpha}, Richardson`s extrapolation was applied to the products to obtain estimates of {Beta}({alpha}) to approximately 40 decimal places. Included are graphs of the points ({alpha},{Beta}({alpha})) for the thirteen values of {alpha} that we considered.

Carpenter, A.J.; Varga, R.S.

1992-07-01T23:59:59.000Z

404

Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR)  

NLE Websites -- All DOE Office Websites (Extended Search)

Ames: Phil Russell, Jens Redemann, NASA Ames: Phil Russell, Jens Redemann, Ames: Phil Russell, Jens Redemann, NASA Ames: Phil Russell, Jens Redemann, Steve Dunagan, Roy Johnson: Steve Dunagan, Roy Johnson: Battelle PND: Connor Flynn, Beat Schmid, Battelle PND: Connor Flynn, Beat Schmid, Evgueni Kassianov Evgueni Kassianov NASA GSFC: Alexander Sinyuk, Brent NASA GSFC: Alexander Sinyuk, Brent Holben Holben , , & AERONET Team & AERONET Team Collaboration involving: Collaboration involving: NASA Ames, Battelle PND, NASA GSFC NASA Ames, Battelle PND, NASA GSFC 4S 4S TAR TAR : : S S pectrometer for pectrometer for S S ky ky - - S S canning, canning, S S un un - - T T racking racking A A tmospheric tmospheric R R esearch esearch 4STAR: 4STAR: Spectrometer Spectrometer for for Sky Sky - - Scanning Scanning , , Sun Sun - - Tracking Tracking Atmospheric Research Atmospheric Research

405

ORISS Isomer and Isobar Spectrometer and Separator for Study of Exotic Decays  

NLE Websites -- All DOE Office Websites (Extended Search)

ORISS Isomer ORISS Isomer and Isobar Spectrometer and Separator for Study of Exotic Decays A. Piechaczek for the 2 EMIS 2007 UNIRIB Consortium * The purpose is to provide a nuclear research facility at ORNL for consortium members * Consortium members: 3 EMIS 2007 * Our Deliverable is Science - Nuclear Physics * We do research * We give scientific reports at meetings * We train students * UNIRIB, with ORISE and ORAU, provides a university atmosphere in a national laboratory 4 Motivation to build ORISS - Oak Ridge Isomer/Isobar Spectrometer and Separator: * Decay studies often possible from yield considerations, but limited by background from isobaric/isomeric contamination * Need high resolution separator for background suppression ORISS predicted performance: * High mass resolving power, M/∆M

406

Spectrometer for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR): Instrument Technology  

SciTech Connect

The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) combines airborne sun tracking and sky scanning with diffraction spectroscopy, to improve knowledge of atmospheric constituents and their links to air-pollution/climate. Direct beam hyper-spectral measurement of optical depth improves retrievals of gas constituents and determination of aerosol properties. Sky scanning enhances retrievals of aerosol type and size distribution. 4STAR measurements will tighten the closure between satellite and ground-based measurements. 4STAR incorporates a modular sun-tracking/ sky-scanning optical head with fiber optic signal transmission to rack mounted spectrometers, permitting miniaturization of the external optical head, and future detector evolution. Technical challenges include compact optical collector design, radiometric dynamic range and stability, and broad spectral coverage. Test results establishing the performance of the instrument against the full range of operational requirements are presented, along with calibration, engineering flight test, and scientific field campaign data and results.

Dunagan, Stephen; Johnson, Roy; Zavaleta, Jhony; Russell, P. B.; Schmid, Beat; Flynn, Connor J.; Redemann, Jens; Shinozuka, Yohei; Livingston, J.; Segal Rozenhaimer, Michal

2013-08-06T23:59:59.000Z

407

X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources  

DOE Patents (OSTI)

Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.

Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang; Goeler, Schweickhard von

1999-05-01T23:59:59.000Z

408

Elimination of ``memory`` from sample handling and inlet system of a mass spectrometer  

DOE Patents (OSTI)

This paper describes a method for preparing the sample handling and inlet system of a mass spectrometer for analysis of a subsequent sample following analysis of a previous sample comprising the flushing of the system interior with supercritical CO{sub 2} and venting the interior. The method eliminates the effect of system ``memory`` on the subsequent analysis, especially following persistent samples such as xenon and krypton.

Chastgner, P.

1991-05-08T23:59:59.000Z

409

Radiation damage control in the BNL hypernuclear spectrometer drift chamber system  

SciTech Connect

A high rate drift chamber system has been in use at the BNL hypernuclear spectrometer system for the past three years. Some of the chambers have accumulated charge doses up to about 0.2 C/cm-wire without showing external signs of aging. The system design and performance will be discussed as well as the results of some laboratory drift chamber aging tests. 5 refs., 9 figs.

Pile, P.H.

1986-01-01T23:59:59.000Z

410

Compact Reflective Imaging Spectrometer Design Utilizing An Immersed Grating And Anamorphic Mirror  

DOE Patents (OSTI)

A compact imaging spectrometer comprising an entrance slit, an anamorphic mirror, a grating, and a detector array. The entrance slit directs light to the anamorphic mirror. The anamorphic mirror receives the light and directs the light to the grating. The grating receives the light from the anamorphic mirror and defracts the light back onto the anamorphic mirror. The anamorphic mirror focuses the light onto a detector array.

Lerner, Scott A. (Corvalis, OR)

2006-01-10T23:59:59.000Z

411

Ge(Li) low level in-situ gamma-ray spectrometer applications  

SciTech Connect

Currently a Ge(Li) spectrometer is being employed for in-situ measurements of radionuclides contained in soil. This is being done at nuclear reactor sites and in complex radionuclide fields at the Nevada Test Site. The methodology and precision of the in-situ spectrometric technique was previously established for analysis of radionuclides in soil. Application of the technique to gaseous and liquid effluents containing radionuclides has shown a great deal of promise. (auth)

Phelps, P.L.; Anspaugh, L.R.; Roth, S.J.; Huckabay, G.W.; Sawyer, D.L.

1973-12-27T23:59:59.000Z

412

SPHERES, Juelich's high-flux neutron backscattering spectrometer at FRM II  

SciTech Connect

SPHERES is a third-generation neutron backscattering spectrometer, located at the 20 MW German neutron source FRM II and operated by the Juelich Centre for Neutron Science. It offers an energy resolution (fwhm) better than 0.65 {mu}eV, a dynamic range of {+-} 31 {mu}eV, and a signal-to-noise ratio of up to 1750:1.

Wuttke, Joachim; Budwig, Alfred; Drochner, Matthias; Kaemmerling, Hans; Kayser, Franz-Joseph; Kleines, Harald; Ossovyi, Vladimir; Pardo, Luis Carlos; Prager, Michael; Richter, Dieter; Schneider, Gerald J.; Schneider, Harald; Staringer, Simon [Forschungszentrum Juelich GmbH, 52425 Juelich (Germany)

2012-07-15T23:59:59.000Z

413

Airborne gamma-ray spectrometer and magnetometer survey: Mitchell Quadrangle, South Dakota. Final report  

SciTech Connect

The results of a high-sensitivity aerial gamma-ray spectrometer survey of the Mitchell Quadrangle, South Dakota are presented. Instrumentation and methods are described in volume 1 of this report. The purpose of this study is to acquire and compile geologic information to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the US. (DMC)

1981-04-01T23:59:59.000Z

414

The influence of the magnetic field on the effect of drag of electrons by phonons in n-Cd{sub x}Hg{sub 1-x}Te  

Science Conference Proceedings (OSTI)

Thermopower in n-Cd{sub 0.2}Hg{sub 0.8}Te (6-100 K) is studied. A large effect of drag of the charge carriers by phonons {alpha}{sub ph} is found. The influence of the magnetic field H on the drag thermopower is considered. It is established that the magnetic field exerts the effect mainly on the electron component of {alpha}{sub ph}. The data are interpreted in the context of the theory taking into account the effect of H on thermopower {alpha}{sub ph}, in which parameter A({epsilon}) proportional to the static force of the drag effect is introduced. By the experimental data {alpha}{sub ph}(T, H), T, and H dependences A({epsilon}) are determined. It is shown that, as H increases, A({epsilon}) sharply decreases. This explains a decrease in {alpha}{sub ph} in the magnetic field, power index k in dependence {alpha}{sub ph} {proportional_to} T{sup -}{kappa}, and narrowing the region of manifestation of the drag effect. It is established that at classically high fields, the drag effect in n-Cd{sub 0.2}Hg{sub 0.8}Te does not vanish.

Aliyev, S. A.; Zulfigarov, E. I.; Selim-Zade, R. I.; Agayev, Z. F., E-mail: agayevz@rambler.ru [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

2009-09-15T23:59:59.000Z

415

Gross alpha/beta determination by liquid scintillation counting  

Science Conference Proceedings (OSTI)

Liquid scintillation counting (LSC) is used to assay liquid samples for both gross alpha and gross beta (including tritium) activity in order to declare these samples clean.'' This method provides several advantages over traditional gross assay techniques including easy sample preparation, no sample self-absorption, short counting times, acceptable lower limits of detection (LLD's), and convenient sample disposal.

Leyba, J.D.

1992-03-01T23:59:59.000Z

416

Gross alpha/beta determination by liquid scintillation counting  

Science Conference Proceedings (OSTI)

Liquid scintillation counting (LSC) is used to assay liquid samples for both gross alpha and gross beta (including tritium) activity in order to declare these samples ``clean.`` This method provides several advantages over traditional gross assay techniques including easy sample preparation, no sample self-absorption, short counting times, acceptable lower limits of detection (LLD`s), and convenient sample disposal.

Leyba, J.D.

1992-03-01T23:59:59.000Z

417

Superscalar Instruction Execution in the 21164 Alpha Microprocessor  

E-Print Network (OSTI)

The 21164 is a new quad-issue, superscalar Alpha microprocessor that executes 1.2 billion instructions per second. Available this January, the 3OO-MHz,0.5-pm CMOS chip delivers an estimated 345/505 SPECint92/SPECfp92 performance. The design's high clock rate, low operational latency, and high-throughput/nonblocking memory systems contribute to this performance.

John H. Edmondson; Paul Rubinfeld; Ronald Preston; Vidya Rajagopalan

1995-01-01T23:59:59.000Z

418

Alpha-tricalcium phosphate-calcium sulfate hybrid bone cement ...  

Science Conference Proceedings (OSTI)

Presentation Title, Alpha-tricalcium phosphate-calcium sulfate hybrid bone ... electron scanning microscopy on the characterization of polymer coating ... Improving the Resistance to Contact and Flexural Damage of Ceramics Using Elastic Gradients ... using phosphoric acid activation by ultrasound and microwave radiation ...

419

TAE SATURATION OF ALPHA PARTICLE DRIVEN INSTABILITY IN TFTR  

E-Print Network (OSTI)

TAE SATURATION OF ALPHA PARTICLE DRIVEN INSTABILITY IN TFTR N. N. Gorelenkovy, Y. Chen, R. B. White. In this paper we apply a recently developed nonlinear theory of kinetic instabilities [5] to calculate calculation had been added to allow an accurate numerical integration of Eq.(14) over the phase space

420

First Results from the Large Area Lyman $\\alpha$ Survey  

E-Print Network (OSTI)

We report on a new survey for z=4.5 Lyman alpha sources, the Large Area Lyman Alpha (LALA) survey. Our survey achieves an unprecedented combination of volume and sensitivity by using narrow-band filters on the new 8192x8192 pixel CCD Mosaic Camera at the 4 meter Mayall telescope of Kitt Peak National Observatory. Well-detected sources with flux and equivalent width matching known high redshift Lyman alpha galaxies (i.e., observed equivalent width above 80 Angstroms and line+continuum flux between 2.6e-17 and 5.2e-17 erg/cm^2/sec in an 80 Angstrom filter) have an observed surface density corresponding to 11000 +- 700 per square degree per unit redshift at z=4.5. Spatial variation in this surface density is apparent on comparison between counts in 6561 and 6730 Angstrom filters. Early spectroscopic followup results from the Keck telescope included three sources meeting our criteria for good Lyman alpha candidates. Of these, one is confirmed as a z=4.52 source, while another remains consistent with either z=4.55...

Rhoads, J E; Dey, A; Stern, D; Spinrad, H; Jannuzi, B; Rhoads, James E.; Malhotra, Sangeeta; Dey, Arjun; Stern, Daniel; Spinrad, Hyron; Jannuzi, Buell

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

The use of chopper spectrometers for cold-to-epithermal neutron scattering at IPNS  

SciTech Connect

A multi-detector chopper spectrometer enables measurements of the scattering function S(Q,E) to be made over a wide range of momentum and energy transfer (Q,E). The application of pulsed-source chopper spectrometers for inelastic measurements at thermal and epithermal energies (50 meV < E < 1000 meV) is well known. Recently at IPNS, we have extended the energy-transfer region down to about 0.5 meV with a resolution of the order of 150 {mu}eV. It is made possible by utilizing the cold-neutron incident spectrum of the 100 K methane moderator in conjunction with a dual beryllium-body rotor system. Neutron incident energies can be changed efficiently over the 4 to 1000 meV region while maintaining an undisturbed sample environment. We describe the operation of the IPNS chopper spectrometers (HRMECS and LRMECS), the instrumental resolution and the background-suppression performance. The capability of measuring inelastic features from 0.5 to 100 meV with an energy resolution of {Delta}E/E{sub 0} = 2.5% is demonstrated by experimental results of crystal-field excitation spectra of a high-Tc superconductor ErBa{sub 2}Cu{sub 3}O{sub 7}. Preliminary data of quasielastic scattering from a room-temperature molten salt AlCl{sub 3}-EMIC are presented.

Loong, C.K.; Donley, L.I.; Ostrowski, G.E.; Kleb, R.; Hammonds, J.P.; Soderholm, L.; Takahashi, S.

1993-09-01T23:59:59.000Z

422

Absolute intensity calibration of the Wendelstein 7-X high efficiency extreme ultraviolet overview spectrometer system  

Science Conference Proceedings (OSTI)

The new high effiency extreme ultraviolet overview spectrometer (HEXOS) system for the stellarator Wendelstein 7-X is now mounted for testing and adjustment at the tokamak experiment for technology oriented research (TEXTOR). One part of the testing phase was the intensity calibration of the two double spectrometers which in total cover a spectral range from 2.5 to 160.0 nm with overlap. This work presents the current intensity calibration curves for HEXOS and describes the method of calibration. The calibration was implemented with calibrated lines of a hollow cathode light source and the branching ratio technique. The hollow cathode light source provides calibrated lines from 16 up to 147 nm. We could extend the calibrated region in the spectrometers down to 2.8 nm by using the branching line pairs emitted by an uncalibrated pinch extreme ultraviolet light source as well as emission lines from boron and carbon in TEXTOR plasmas. In total HEXOS is calibrated from 2.8 up to 147 nm, which covers most of the observable wavelength region. The approximate density of carbon in the range of the minor radius from 18 to 35 cm in a TEXTOR plasma determined by simulating calibrated vacuum ultraviolet emission lines with a transport code was 5.5x10{sup 17} m{sup -3} which corresponds to a local carbon concentration of 2%.

Greiche, Albert; Biel, Wolfgang; Marchuk, Oleksandr [Institut fuer Energieforschung-Plasmaphysik, Forschungszentrum Juelich GmbH, EURATOM Association, Trilateral Euregio Cluster, D-52425 Juelich (Germany); Burhenn, Rainer [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-17491 Greifswald (Germany)

2008-09-15T23:59:59.000Z

423

An Ion Doppler Spectrometer Instrument for Ion Temperature and Flow Measurements on SSPX  

DOE Green Energy (OSTI)

A high-resolution ion Doppler spectrometer has been installed on the Sustained Spheromak Plasma Experiment to measure ion temperatures and plasma flow. The system is composed of a 1 meter focal length Czerny-Turner spectrometer with diffraction grating line density of 2400 lines/mm, which allows for first order spectra between 300 and 600 nm. A 16-channel photomultiplier tube detection assembly combined with output coupling optics provides a spectral resolution of 0.0126 nm per channel. We calculate in some detail the mapping of curved slit images onto the linear detector array elements. This is important in determining wavelength resolution and setting the optimum vertical extent of the slit. Also, because of the small wavelength window of the IDS, a miniature fiber optic survey spectrometer sensitive to a wavelength range 200 to 1100 nm and having resolution 0.2 nm, is used to obtain a time-integrated spectrum for each shot to verify specific impurity line radiation. Several measurements validate the systems operation. Doppler broadening of C III 464.72 nm line in the plasma shows time-resolved ion temperatures up to 250 eV for hydrogen discharges, which is consistent with neutral particle energy analyzer measurements. Flow measurements show a sub-Alfvenic plasma flow ranging from 5 to 45 km/s for helium discharges.

King, J D; McLean, H S; Wood, R D; Romero-Talamas, C A; Moller, J M; Morse, E C

2008-05-19T23:59:59.000Z

424

Superresolution of a compact neutron spectrometer at energies relevant for fusion diagnostics  

SciTech Connect

The ability to achieve resolution that is better than the instrument resolution (i.e., superresolution) is well known in optics, where it has been extensively studied. Unfortunately, there are only a handful of theoretical studies concerning superresolution of particle spectrometers, even though experimentalists are familiar with the enhancement of resolution that is achievable when appropriate methods of data analysis are used, such as maximum entropy and Bayesian methods. Knowledge of the superresolution factor is in many cases important. For example, in applications of neutron spectrometry to fusion diagnostics, the temperature of a burning plasma is an important physical parameter which may be inferred from the width of the peak of the neutron energy spectrum, and the ability to determine this width depends on the superresolution factor. Kosarev has derived an absolute limit for resolution enhancement using arguments based on a well known theorem of Shannon. Most calculations of superresolution factors in the literature, however, are based on the assumption of Gaussian, translationally invariant response functions and therefore not directly applicable to neutron spectrometers which typically have response functions not satisfying these requirements. In this work, we develop a procedure that allows us to overcome these difficulties and we derive estimates of superresolution for liquid scintillator spectrometers of a type commonly used for neutron measurements. Theoretical superresolution factors are compared to experimental results.

Reginatto, M.; Zimbal, A. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany)

2011-03-14T23:59:59.000Z

425

Physical Interactions between Mcm10, DNA, and DNA Polymerase [alpha  

SciTech Connect

Mcm10 is an essential eukaryotic protein required for the initiation and elongation phases of chromosomal replication. Specifically, Mcm10 is required for the association of several replication proteins, including DNA polymerase {alpha} (pol {alpha}), with chromatin. We showed previously that the internal (ID) and C-terminal (CTD) domains of Mcm10 physically interact with both single-stranded (ss) DNA and the catalytic p180 subunit of pol {alpha}. However, the mechanism by which Mcm10 interacts with pol {alpha} on and off DNA is unclear. As a first step toward understanding the structural details for these critical intermolecular interactions, x-ray crystallography and NMR spectroscopy were used to map the binary interfaces between Mcm10-ID, ssDNA, and p180. The crystal structure of an Mcm10-ID {center_dot} ssDNA complex confirmed and extended our previous evidence that ssDNA binds within the oligonucleotide/oligosaccharide binding-fold cleft of Mcm10-ID. We show using NMR chemical shift perturbation and fluorescence spectroscopy that p180 also binds to the OB-fold and that ssDNA and p180 compete for binding to this motif. In addition, we map a minimal Mcm10 binding site on p180 to a small region within the p180 N-terminal domain (residues 286-310). These findings, together with data for DNA and p180 binding to an Mcm10 construct that contains both the ID and CTD, provide the first mechanistic insight into how Mcm10 might use a handoff mechanism to load and stabilize pol {alpha} within the replication fork.

Warren, Eric M.; Huang, Hao; Fanning, Ellen; Chazin, Walter J.; Eichman, Brandt F.; (Vanderbilt)

2009-10-21T23:59:59.000Z

426

A Near-Infrared Diode Laser Spectrometer for the In Situ Measurement of Methane and Water Vapor from Stratospheric Balloons  

Science Conference Proceedings (OSTI)

The Spectromètre à Diodes Laser Accordables (SDLA), a balloonborne near-infrared diode laser spectrometer, was developed to provide simultaneous in situ measurements of methane and water vapor in the troposphere and the lower stratosphere. The ...

Georges Durry; Ivan Pouchet

2001-09-01T23:59:59.000Z

427

A Diode Laser Spectrometer for the In Situ Measurement of the HNO3 Content of Polar Stratospheric Clouds  

Science Conference Proceedings (OSTI)

A new instrument realized for measuring the HNO3 concentration in air is described. The device is a midinfrared absorption spectrometer based on a tunable diode laser and a multipass absorption cell. The instrument is specifically designed for ...

G. Toci; P. Mazzinghi; M. Vannini

1999-10-01T23:59:59.000Z

428

High Field Magnet R&D |Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

High Field Magnet R&D High Field Magnet R&D The Superconducting Magnet Division is developing advanced magnet designs and magnet-related technologies for high field accelerator magnets. We are currently working on magnets for three inter-related programs: High Field Magnets for Muon Collider Papers, Presentations Common Coil Magnets Papers, Presentations Interaction Region Magnets Papers, Presentations High Temperature Superconductor (HTS) Magnets Papers, Presentations This is part of a multi-lab superconducting magnet development program for new accelerator facilities that would be part of the U.S. High Energy Physics program. These programs (@BNL, @FNAL, @LBNL) are quite complimentary to each other, so that magnet designs and technologies developed at one laboratory can be easily transferred to another. The BNL

429

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Cool Magnetic Molecules Cool Magnetic Molecules Print Wednesday, 25 May 2011 00:00 Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

430

Pulse magnetic welder  

DOE Patents (OSTI)

A welder is described for automated closure of fuel pins by a pulsed magnetic process in which the open end of a length of cladding is positioned within a complementary tube surrounded by a pulsed magnetic welder. Seals are provided at each end of the tube, which can be evacuated or can receive tag gas for direct introduction to the cladding interior. Loading of magnetic rings and end caps is accomplished automatically in conjunction with the welding steps carried out within the tube.

Christiansen, D.W.; Brown, W.F.

1984-01-01T23:59:59.000Z

431

Magnetic latching solenoid  

DOE Patents (OSTI)

This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized.

Marts, Donna J. (Idaho Falls, ID); Richardson, John G. (Idaho Falls, ID); Albano, Richard K. (Idaho Falls, ID); Morrison, Jr., John L. (Idaho Falls, ID)

1995-01-01T23:59:59.000Z

432

Estimation of the alpha decay half-lives D. N. Poenaru and M. Ivascu  

E-Print Network (OSTI)

semiempirical relationship is derived on the grounds of the fission theory of alpha decay. It takes }, based on the fission theory of alpha decay [16] have been derived and was briefly presented in refe

Paris-Sud XI, Université de

433

V-075: EMC AlphaStor Command Injection and Format String Flaws...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5: EMC AlphaStor Command Injection and Format String Flaws Let Remote Users Execute Arbitrary Code V-075: EMC AlphaStor Command Injection and Format String Flaws Let Remote Users...

434

Nanostructrured Magnetic Materials  

Science Conference Proceedings (OSTI)

Aug 8, 2013 ... The demand for OFF-ON becomes increasingly important as ... The residual magnetic flux density and maximum energy product of the ...

435

Magnetically leviated superconducting bearing  

DOE Patents (OSTI)

A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

Weinberger, Bernard R. (Avon, CT); Lynds, Jr., Lahmer (Glastonbury, CT)

1993-01-01T23:59:59.000Z

436

Rare Earth Magnets  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Performance and Endurance of Nd-Fe-B Sintered Magnets in E-Motor Application Conditions: Martina Moore1; Ralph Sueptitz1; Margitta ...

437

Rare Earth Magnets  

Science Conference Proceedings (OSTI)

Aug 8, 2013 ... Current high performance permanent magnets (PM) for traction motors of (hybrid) electric vehicles use substantial amount of Dy in Nd-Fe-B ...

438

Magnetic Materials and Properties  

Science Conference Proceedings (OSTI)

Aug 5, 2013 ... Following vacuum distillation of the Mg-RE alloy, 98% pure RE metals can be recovered, which are then used to synthesize permanent magnet ...

439

Magnetism Highlights| Neutron Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetism Magnetism SHARE Magnetism Highlights 1-5 of 5 Results ARCS maps collaborative magnetic spin behavior in iron telluride December 01, 2011 - Researchers have long thought that magnetism and superconductivity are mutually exclusive. The former typically involves localized atomic electrons. The latter requires freely propagating, itinerant electrons. Unexpected Magnetic Excitations in Doped Insulator Surprise Researchers October 01, 2011 - When doping a disordered magnetic insulator material with atoms of a nonmagnetic material, the conventional wisdom is that the magnetic interactions between the magnetic ions in the material will be weakened. Neutron Analysis Reveals Unique Atomic-Scale Behavior of "Cobalt Blue" September 01, 2011 - Neutron scattering studies of "cobalt blue," a

440

PGAA Spectrometer  

Science Conference Proceedings (OSTI)

... of the peaks at these energies reveal their ... resulting in higher counting efficiency and better sensitivity, especially in the energy region below ...

2012-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Alpha-Particle Condensate in Nuclear Matter at Normal Density and Statistics of Composite Bosons  

E-Print Network (OSTI)

It is proved that alpha-particle states are well described by the Elliott SU(3) model. This result is used to analyze the alpha-particle condensation effect. It is shown that these states possess the basic attributes of the alpha-condensate and, also, the normal nuclear density on frequent occasions. The statistics of alpha-particles (and of arbitrary composite bosons) turns out to be something other than the Bose-Einstein, Fermi-Dirac statistics, and parastatistics.

I. A. Gnilozub; S. D. Kurgalin; Yu. M. Tchuvil'sky

2004-05-13T23:59:59.000Z

442

Program Considerations for Addressing Alpha Emitting Radionuclides at Nuclear Power Plants  

Science Conference Proceedings (OSTI)

This report is a technical reference for assessing the magnitude and potential dose impact of alpha emitting nuclides at nuclear power plants with elevated levels of alpha contamination. Since alpha emitting nuclides are not always easy to detect and can have serious health consequences, quantifying their presence and assessing their impact can be important. This report provides several options for modifying a radiation protection program to address elevated levels of alpha contamination.

2001-11-12T23:59:59.000Z

443

Gross Alpha and Gross Beta Measurements in Coal Combustion Product Leachate  

Science Conference Proceedings (OSTI)

The objective of this report was to provide information to help interpret gross alpha and gross beta concentrations in coal combustion product (CCP) leachate. This objective was accomplished by chemically characterizing 15 field leachate samples that were collected at three CCP management facilities. The leachate samples were analyzed for gross alpha and gross beta concentrations and for the potential individual alpha and beta emitters in solution. Gross alpha concentrations at the three sites ranged fro...

2008-09-22T23:59:59.000Z

444

Solid-State Dynamic Nuclear Polarization at 263 GHz: Spectrometer Design and Experimental Results  

E-Print Network (OSTI)

Dynamic Nuclear Polarization (DNP) experiments transfer polarization from electron spins to nuclear spins with microwave irradiation of the electron spins for enhanced sensitivity in nuclear magnetic resonance (NMR) ...

Rosay, Melanie

445

BEPC-II Magnet Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

BEPC-II Magnet Project BEPC-II Magnet Project Project Overview The BEPC-II magnets are Interaction Region magnets to be used as part of an upgrade to the Beijing Electron Positron Collider. Two magnets will be produced, both of which will be inserted within the solenoidal detector at one of the collision points. Since the best use of the quadrupole focusing in this case requires placing the magnet as close to the collision point as possible, these magnets will be used within the magnetic field of the detector. This constrains the materials that can be used for construction to only non-magnetic materials. It also places severe demands on the structure of the magnet and it's holding supports due to the reaction forces between the solenoid and the magnet. To create the coil pattern for the final magnet, the coils will be

446

alpha-amylase and Glucose Oxidase as Promising Improvers for Wheat Bread  

Science Conference Proceedings (OSTI)

The effects of alpha-amylase and glucose oxidase as bread improvers on the textural and thermal properties of bread were evaluated by the rapid viscosity analysis and differential scanning calorimetry. It was found that alpha-amylase and glucose oxidase ... Keywords: alpha-amylase, Glucose oxidase, viscosity, Bread quality

Jie Zeng; Haiyan Gao; Guanglei Li; Xinhong Liang

2011-04-01T23:59:59.000Z

447

The n+n+{alpha} system in a continuum Faddeev formulation  

Science Conference Proceedings (OSTI)

The continuum Faddeev equations for the neutron-neutron-alpha (n+n+{alpha}) system are formulated for a general interaction as well as for finite rank forces. In addition, the capture process n+n+{alpha}{yields}{sup 6}He+{gamma} is derived.

Khaldi, K. [Institute of Nuclear and Particle Physics, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States); Faculte des Sciences, Universite de Boumerdes, 35000 Boumerdes (Algeria); Elster, Ch. [Institute of Nuclear and Particle Physics, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States); Gloeckle, W. [Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

2010-11-15T23:59:59.000Z

448

Passive magnetic bearing configurations  

Science Conference Proceedings (OSTI)

A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

Post, Richard F. (Walnut Creek, CA)

2011-01-25T23:59:59.000Z

449

EXOTIC MAGNETS FOR ACCELERATORS.  

SciTech Connect

Over the last few years, several novel magnet designs have been introduced to meet the requirements of new, high performance accelerators and beam lines. For example, the FAIR project at GSI requires superconducting magnets ramped at high rates ({approx} 4 T/s) in order to achieve the design intensity. Magnets for the RIA and FAIR projects and for the next generation of LHC interaction regions will need to withstand high doses of radiation. Helical magnets are required to maintain and control the polarization of high energy protons at RHIC. In other cases, novel magnets have been designed in response to limited budgets and space. For example, it is planned to use combined function superconducting magnets for the 50 GeV proton transport line at J-PARC to satisfy both budget and performance requirements. Novel coil winding methods have been developed for short, large aperture magnets such as those used in the insertion region upgrade at BEPC. This paper will highlight the novel features of these exotic magnets.

WANDERER, P.

2005-09-18T23:59:59.000Z

450

Measurement of the poloidal magnetic field in the PBX-M tokamak using the motional Stark effect  

DOE Green Energy (OSTI)

Polarimetry measurements of the Doppler-shifted H/sub ..cap alpha../ emission from a hydrogen neutral beam on the PBX-M tokamak have been employed in a novel technique for obtaining q(0) and poloidal magnetic field profiles. The electric field from the beam particle motion across the magnetic field (E = V/sub beam/ /times/ B) causes a wavelength splitting of several angstroms, and polarization of the emitted radiation (Stark effect). Viewed transverse to the fields, the emission is linearly polarized with the angle of polarization related to the direction of the magnetic field. 14 refs., 5 figs.

Levinton, F.M.; Fonck, R.J.; Gammel, G.M.; Kaita, R.; Kugel, H.W.; Powell, E.T.; Roberts, D.W.

1989-05-01T23:59:59.000Z

451

Small-Molecule Inhibition of TNF-alpha  

NLE Websites -- All DOE Office Websites (Extended Search)

Small-Molecule Inhibition of TNF-alpha Tumour necrosis factor is a polypeptide cytokine involved in inflammation and the acute phase response. TNF-alpha is present in larger quantities in persons with rheumatoid arthritis or Crohn's disease. Direct inhibition of TNF-a by the commercial biological agents etanercept (Enbrel), infliximab (Remicade), adalimumab (Humira), has produced significant advances in rheumatoid arthritis treatment and validated the extra-cellular inhibition of this proinflammatory cytokine as an effective therapy. However, despite considerable incentives, viable leads for analogous small-molecule inhibitors of TNF-a have not been reported (1). Such drugs with attendant advantages in manufacturing, patient accessibility, administration, and compliance would represent a major advance in the treatment of TNF-a mediated diseases.

452

Lyman Alpha Flux Power Spectrum and Its Covariance  

E-Print Network (OSTI)

We analyze the flux power spectrum and its covariance using simulated Lyman alpha forests. We find that pseudo-hydro techniques are good approximations of hydrodynamical simulations at high redshift. However, the pseudo-hydro techniques fail at low redshift because they are insufficient for characterizing some components of the low-redshift intergalactic medium, notably the warm-hot intergalactic medium. Hence, to use the low-redshift Lyman alpha flux power spectrum to constrain cosmology, one would need realistic hydrodynamical simulations. By comparing one-dimensional mass statistics with flux statistics, we show that the nonlinear transform between density and flux quenches the fluctuations so that the flux power spectrum is much less sensitive to cosmological parameters than the one-dimensional mass power spectrum. The covariance of the flux power spectrum is nearly Gaussian. As such, the uncertainties of the underlying mass power spectrum could still be large, even though the flux power spectrum can be p...

Zhan, H; Eisenstein, D J; Katz, N; Zhan, Hu; Dave, Romeel; Eisenstein, Daniel; Katz, Neal

2005-01-01T23:59:59.000Z

453

Filament and Flare Detection in H{\\alpha} image sequences  

E-Print Network (OSTI)

Solar storms can have a major impact on the infrastructure of the earth. Some of the causing events are observable from ground in the H{\\alpha} spectral line. In this paper we propose a new method for the simultaneous detection of flares and filaments in H{\\alpha} image sequences. Therefore we perform several preprocessing steps to enhance and normalize the images. Based on the intensity values we segment the image by a variational approach. In a final postprecessing step we derive essential properties to classify the events and further demonstrate the performance by comparing our obtained results to the data annotated by an expert. The information produced by our method can be used for near real-time alerts and the statistical analysis of existing data by solar physicists.

Riegler, Gernot; Pötzi, Werner; Veronig, Astrid

2013-01-01T23:59:59.000Z

454

Alpha Solarco`s Photovoltaic Concentrator Development program  

DOE Green Energy (OSTI)

This report details the work done under Sandia`s Photovoltaic Concentrator Development contract, funded jointly by Alpha Solarco and the US Department of Energy. It discusses improvements made to the cell assembly and module design of Alpha Solarco`s point-focus, high-concentration photovoltaic module. The goals of this effort were to increase the module efficiency, reduce the manufacturing cost of the cell assembly, and increase product reliability. Redesign of the secondary optical element achieved a 4 percent increase in efficiency due to better cell fill factors and offtrack performance. New, lower cost materials were identified for the secondary optical element, the optical couple between the secondary optical element and the cell, and the cell assembly electrical insulator. Manufacturing process improvements and test equipment are also discussed.

Anderson, A.; Bailor, B.; Carroll, D. [Alpha Solarco, Inc., Phoenix, AZ (United States)] [and others

1995-10-01T23:59:59.000Z

455

AIR ALPHA PROPORTIONAL COUNTER INSENSITIVE TO ATMOSPHERIC HUMIDITY  

SciTech Connect

A conventional alpha proportional counter which uses air as the counter gas is sensitive to high relative humidity and generates spurious pulses that cannot be distinguished from actual alpha pulses. It was found possible to operate such a counter satisfactorily at high relative humidity by passing a small current ( approximates 15 ma) through the center wire. In this manner the center wire is heated and the relative humidity of the surrounding sheath of air is reduced sufficiently so that operation of the counter at high relative humidity is comparable to operation with dry air, Two different mechanisms are proposed for the formation of spurious pulses in such a counter at high relative humidity. (auth)

Ferrari, A.M.R.; Borkowski, C.J.

1962-10-01T23:59:59.000Z

456

Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

3 - 6/13/06 3 - 6/13/06 Superconducting Magnet Division S&T Committee Program Review June 22-23, 2006 Conference Room A, Bldg. 725, BNL DRAFT AGENDA Thursday, June 22 0830 Executive Session to address the charge S. Aronson (25 min) 0855 Welcome S. Aronson (5 min) 0900 Superconducting Magnet Division Status & M. Harrison (45 + 15 min) Issues - mission statement, core competencies, themes, program, problems, etc. 1000 Themes - Nb3Sn, HTS, Direct wind, Accelerator integration, P. Wanderer (20 + 10 min) rapid cycling Core Competencies 1030 Superconducting Materials A. Ghosh (20 + 5 min) 1055 Break 1110 Magnetic Design R. Gupta (20 + 5 min) 1135 Magnet Construction M. Anerella (20 + 5 min) 1200 Magnet Testing G. Ganetis (20 + 5 min)

457

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

458

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

459

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

460

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

Note: This page contains sample records for the topic "alpha magnetic spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to