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Note: This page contains sample records for the topic "angular-range chopper spectrometer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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1

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

2

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

3

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

4

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...

5

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... almost all of the high energy neutrons and gamma-rays in the initial ... disk choppers that collectively produce clean monochromatic bursts of neutrons ...

6

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

7

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 ...

8

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

9

Choppers - Instrument Support | ORNL Neutron Sciences  

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

Neutron Choppers Neutron Choppers The primary mission of the Neutron Chopper Team is to provide functional, reliable, safe, and operationally proven neutron chopper systems as required by the SNS instrument beam lines. Type of Choppers Activities Facilities Equipment TOP2 T0 chopper installed and operating in a CTF lower level chopper test bay. (Click for a larger picture) Chopper technician Bill Jordan recording chopper balance data. Types of Choppers Neutron choppers are rotating mechanical devices designed to block the neutron beam for some fraction of each revolution of the chopper. Our goal is to have at least three different functional classes of neutron choppers available for user experiments. Most, if not all, of these will be designed in standard forms that are interchangeable among the instruments. Most

10

Combination field chopper and battery charger  

DOE Patents (OSTI)

A power transistor used in a chopper circuit to control field excitation of a vehicle motor when in a power mode is also used to control charging current from an a-c to d-c rectifier to the vehicle battery when in a battery charging mode. Two isolating diodes and a small high frequency filter inductor are the only elements required in the chopper circuit to reconfigure the circuit for power or charging modes of operation.

Steigerwald, R.L.; Crouch, K.E.; Wilson, J.W.A.

1979-08-13T23:59:59.000Z

11

Combination field chopper and battery charger  

SciTech Connect

A power transistor used in a chopper circuit to control field excitation of a vehicle motor when in a power mode is also used to control charging current from an a-c to d-c rectifier to the vehicle battery when in a battery charging mode. Two isolating diodes and a small high frequency filter inductor are the only elements required in the chopper circuit to reconfigure the circuit for power or charging modes of operation.

Steigerwald, Robert L. (Scotia, NY); Crouch, Keith E. (Pittsfield, MA); Wilson, James W. A. (Scotia, NY)

1981-01-01T23:59:59.000Z

12

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... Jürgen Räbiger, Jamie Reardon, Mike Rinehart, Connie Runkles, Ivan Schroder, Lyn Shuman, Scott Slifer, Denise Sullivan, Thuan Thai, Pat Tobin ...

13

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... JG Barker, DFR Mildner, JA Rodriguez, and P. Thiyagarajan, "Neutron transmission of single-crystal magnesium fluoride", J. Appl. Cryst. ...

14

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... The sharp dips in the beam intensity at 3.35 Å and 6.70 Å are ... The graphite filter is used to eliminate high energy neutrons (for a detailed explanation ...

15

DISK CHOPPER TIME-OF-FLIGHT SPECTROMETER (DCS)  

Science Conference Proceedings (OSTI)

... the hole to get hold of a cover plate. ... username for dcs, solo and the Windows computer is ... logo will appear, followed by the DCS Control window: ...

16

FERMI CHOPPER TIME-OF-FLIGHT SPECTROMETER (FCS)  

Science Conference Proceedings (OSTI)

... Instruments and Methods in Physics Research Section ... and Evidence for Cooperative Hydrogen Bonding", J. Phys. ... A. Biswas, RL Greene, W. Ratcliff ...

17

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...

18

Accurate Airborne Surface Temperature Measurements with Chopper-stabilized Radiometers  

Science Conference Proceedings (OSTI)

The accuracy of chopper-stabilized radiometers for the meteorological measurement of surface temperatures was investigated during a series of airborne trails, including tests at high altitude using a pressurized aircraft. The significant finding ...

Dieter Lorenz

1991-06-01T23:59:59.000Z

19

Broad-band chopper for a CW proton linac at Fermilab  

E-Print Network (OSTI)

Requirements and technical limitations to the bunch-by-bunch chopper for the Fermilab Project X are discussed.

Gianfelice-Wendt, E; Solyak, N; Nagaitsev, S; Sun, D

2012-01-01T23:59:59.000Z

20

A prototype chopper for synchrotron time-resolved crystallographic measurements  

Science Conference Proceedings (OSTI)

A mechanical x-ray chopper has been designed to perform microsecond time-resolved crystallographic studies at the DIAMOND synchrotron I19 beamline. It consists of two asymmetric absorbers rotating synchronously at frequencies from 0 to 50 Hz in the same direction around a rotation axis that is parallel to the x-ray beam. The duration of the x-ray pulses produced by the chopper is determined by the relative phase between the two blades, which can be adjusted. The chopper system presented in this paper offers a time resolution suitable for conducting in situ experiments that afford the crystal structure of materials while in their transient (>10 {mu}s) photoactivated excited states.

Husheer, S. L. G. [Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Cole, J. M. [Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Department of Physics, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Department of Chemistry, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3 (Canada); Department of Physics, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3 (Canada); D'Almeida, T. [Department of Physics, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Teat, S. J. [Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD (United Kingdom)

2010-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

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

22

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

23

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

24

Comprehensive phonon "map" offers direction for engineering new  

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

4 4 SHARE Comprehensive phonon "map" offers direction for engineering new thermoelectric devices Olivier Delaire, researcher in Oak Ridge National Laboratory's Materials Science and Technology Division, at the Spallation Neutron Source's Wide Angular-Range Chopper Spectrometer. Using neutrons to map heat as it propagates through materials, Delaire and his research group are studying how to design better thermoelectric devices that convert a temperature difference into an electric voltage. Olivier Delaire, researcher in Oak Ridge National Laboratory's Materials Science and Technology Division, at the Spallation Neutron Source's Wide Angular-Range Chopper Spectrometer. Using neutrons to map heat as it propagates through materials, Delaire and his research group are studying

25

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

26

HARDWARE IMPLEMENTATION AND TEST RESULTS OF PEP CHOPPER MAGNET POWER SUPPLY SYSTEM  

E-Print Network (OSTI)

used as the 0 to 600 volt DC supply for the chopper family.s~gnal and converts it to 24 volt"' firing pulse via a ramp4 are detected at zel"o volts. The bar shol"ts the DC output

Jackson, L.T.

2010-01-01T23:59:59.000Z

27

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

28

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

29

SNS Instrument System Beam Lines | ORNL Neutron Sciences  

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

SNS Instrument Beam Lines SNS Instrument Beam Lines This diagram shows the beam lines designated for currently funded instruments. Clicking on an instrument description will take you to the page for that instrument. Clicking anywhere else on the image will open a full-size, printable PDF file. SNS Instrument Layout Backscattering Spectrometer (BASIS) Disordered Materials Diffractometer (NOMAD) Wide Angular-Range Chopper Spectrometer (ARCS) Fine-Resolution Fermi Chopper Spectrometer (SEQUOIA) Coming Soon - Vibrational Spectrometer (VISION) Neutron Spin Echo (NSE) Hybrid Spectrometer (HYSPEC) Fundamental Neutron Physics Beamline (FNPB) Single Crystal Diffractometer (TOPAZ) Versatile Neutron Imaging Instrument (VENUS) Macromolecular Diffractometer (MaNDi) Powder Diffractometer (POWGEN3) Engineering Diffractometer (VULCAN) Extended Q-Range Small Angle Neutron Diffractometer (EQ-SANS) Cold Neutron Chopper Spectrometer (CNCS) Liquids (horizontal surface) Reflectometer (LR) Magnetic Advanced Grazing InCidence Spectrometer (MAGICS) High Pressure Diffractometer (SNAP) Coming Soon - Elastic Diffuse Scattering Spectrometer (CORELLI)

30

Particle swarm optimisation for power quality improvement of a 12-pulse rectifier-chopper fed LCI-synchronous motor drive  

Science Conference Proceedings (OSTI)

This paper investigates the optimised passive filter combination for power quality improvement of a 12-pulse rectifier-chopper fed load commutated inverter LCI based synchronous motor SM drive. The search of optimised component values of passive filter ...

Sanjeev Singh; Bhim Singh

2012-03-01T23:59:59.000Z

31

Broad-band chopper for a CW proton linac at Fermilab  

SciTech Connect

The future Fermilab program in the high energy physics is based on a new facility called the Project X [1] to be built in the following decade. It is based on a 3 MW CW linear accelerator delivering the 3 GeV 1 mA H{sup -} beam to a few experiments simultaneously. Small fraction of this beam will be redirected for further acceleration to 8 GeV to be injected to the Recycler/Main Injector for a usage in a neutrino program and other synchrotron based high energy experiments. Requirements and technical limitations to the bunch-by-bunch chopper for the Fermilab Project X are discussed.

Gianfelice-Wendt, E.; Lebedev, V.A.; Solyak, N.; Nagaitsev, S.; Sun, D.; /Fermilab

2011-03-01T23:59:59.000Z

32

Randomized PWM for conductive EMI reduction in DC-DC choppers  

E-Print Network (OSTI)

In this paper, a comparative investigation of different random modulation schemes against the normal pulsewidth modulation (PWM) for the DC motor drive with step-down chopper (buck) and half-bridge configuration is presented. For this purpose, an experimental setup with DSP2 board has been developed. The board consists of the signal processor TMS320C32 which is suitable for verifying the different modulations strategies. The effectiveness of randomization on spreading the dominating frequencies that normally exist in constantfrequency PWM schemes is evaluated by the power spectral density (PSD) estimations in the low-frequency range. Finally, one universal demo board with two power converters configuration (driven by the micro controller PICF16F876) has been used in EMI measurements to comply with the CISPR 25 (or EN 55025) regulations. 1

Franc Mihali?; Dejan Kos

2005-01-01T23:59:59.000Z

33

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...

34

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

35

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

36

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

37

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

38

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

39

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

40

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

Note: This page contains sample records for the topic "angular-range chopper 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

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

42

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

43

Capabilities of the ARCS Instrument - ORNL Neutron Sciences  

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

Capabilities of the ARCS Instrument Capabilities of the ARCS Instrument ARCS Overview 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

44

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

45

Versatile high-repetition-rate phase-locked chopper system for fast timing experiments in the vacuum ultraviolet and x-ray spectral region  

SciTech Connect

A novel light chopper system for fast timing experiments in the vacuum-ultraviolet (VUV) and x-ray spectral region has been developed. It can be phase-locked and synchronized with a synchrotron radiation storage ring, accommodating repetition rates in the range of {approx}8 to {approx}120 kHz by choosing different sets of apertures and subharmonics of the ring frequency (MHz range). Also the opening time of the system can be varied from some nanoseconds to several microseconds to meet the needs of a broad range of applications. Adjusting these parameters, the device can be used either for the generation of single light pulses or pulse packages from a microwave driven, continuous He gas discharge lamp or from storage rings which are otherwise often considered as quasi-continuous light sources. This chopper can be utilized for many different kinds of experiments enabling, for example, unambiguous time-of-flight (TOF) multi-electron coincidence studies of atoms and molecules excited by a single light pulse as well as time-resolved visible laser pump x-ray probe electron spectroscopy of condensed matter in the valence and core level region.

Plogmaker, Stefan; Johansson, Erik M. J.; Rensmo, Haakan; Feifel, Raimund; Siegbahn, Hans [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Linusson, Per [Department of Physics, Stockholm University, AlbaNova University Center, SE-106 91 Stockholm (Sweden); Eland, John H. D. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ (United Kingdom); Baker, Neville [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ (United Kingdom)

2012-01-15T23:59:59.000Z

46

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

47

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

48

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

49

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

50

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...

51

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

52

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

53

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

54

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 ...

55

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...

56

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

57

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

58

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

59

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...

60

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...

Note: This page contains sample records for the topic "angular-range chopper 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

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...

62

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

63

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

64

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

65

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

66

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

67

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

68

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

69

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

70

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

71

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 &...

72

Progress with PXIE MEBT Chopper  

Science Conference Proceedings (OSTI)

A capability to provide a large variety of bunch patterns is crucial for the concept of the Project X serving MW-range beam to several experiments simultaneously. This capability will be realized by the Medium Energy Beam Transport's (MEBT) chopping system that will divert 80% of all bunches of the initially 5 mA, 2.1 MeV CW 162.5 MHz beam to an absorber according to a pre-programmed bunch-by-bunch selection. Being considered one of the most challenging components, the chopping system will be tested at the Project X Injector Experiment (PXIE) facility that will be built at Fermilab as a prototype of the Pojrect X front end. The bunch deflection will be made by two identical sets of travelling-wave kickers working in sync. Presently, two versions of the kickers are being investigated: a helical 200 Ohm structure with a switching-type 500 V driver and a planar 50 Ohm structure with a linear {+-} 250 V amplifier. This paper describes the chopping system scheme and functional specifications for the kickers, present results of electromagnetic measurements of the models, discuss possible driver schemes, and show a conceptual mechanical design.

Lebedev, V.; Chen, A.; Pasquinelli, R; Peterson, D.; Saewert, G.; Shemyakin, A.; Sun, D.; Wendt, M.; /Fermilab; Tang, T.; /SLAC

2012-05-01T23:59:59.000Z

73

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

74

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

75

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

76

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

77

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

78

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

79

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

80

Published Research 2012 | ORNL Neutron Sciences  

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

2 2 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A Abdou A., Wendel M., Riemer B., Volpenheini E., Brewster R., "Two-phase flow simulations of protective gas layer for Spallation Neutron Source target", ASME International Mechanical Engineering Congress and Exposition 2011. Abernathy D. L., Stone M. B., Loguillo M. J., Lucas M. S., Delaire O., Tang X., Lin J. Y.Y., Fultz B., "Design and operation of the wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source", Review of Scientific Instruments 83, 15114. Aczel A. A., Granroth G. E., MacDougall G. J., Buyers W. J.L.,

Note: This page contains sample records for the topic "angular-range chopper 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.


81

Published Research 2008 | ORNL Neutron Sciences  

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

8 8 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A Abernathy D. L., "ARCS: a wide Angular-Range Chopper Spectrometer at the SNS", Notiziario Neutroni e Luce di Sincrotrone 13, 4-7 . Ambaye H., Goyette R., Parizzi A., Klose F., "SNS magnetism reflectometer", Neutron News 19, 11-13. Anderson I. S., Horak C. M., Counce D. M., Ekkebus A. E., "ORNL Neutron Sciences Annual Report for 2007", ORNL/TM-2009/111. Ankner J. F., Tao X., Halbert C. E., Browning J. F., Kilbey II S. M., Swader O. A., admun M. S., Kharlampieva E., Sukhishvili S. A., "The SNS

82

Contacts | ORNL Neutron Sciences  

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

Science Points of Contact Science Points of Contact Name Research Area Doug Abernathy Wide Angular-Range Chopper Spectrometer (ARCS). Atomic-scale dynamics at thermal and epithermal energies Ke An Engineering Materials Diffractometer (VULCAN). Residual stress, deformation mechanism of materials, phase transitions/transformation, and in situ/operando neutron diffraction in material systems (e.g., working batteries). John Ankner Liquids Reflectometer (LR). Density profiles normal to the surface at liquid surfaces and liquid interfaces Bryan Chakoumakos Nuclear and magnetic crystal structure systematics and structure-property relationships among inorganic materials, powder and single-crystal neutron and x-ray diffraction methods Leighton Coates Macromolecular Neutron Diffractometer (MaNDi). Protein crystallography, biological structure and function

83

Published Research 2008 | ORNL Neutron Sciences  

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

8 8 Published Research 2008 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: A B C D E F G H I J K L M N O P R S T W X Y Z A K. Abe, A. Kohyama, S. Tanaka, C. Namba, T. Terai, T. Kunugi, T. Muroga, A. Hasegawa, A. Sagara, S. Berk, S. J. Zinkle, D. K. Sze, D. A. Petti, M. A. Abdou, N. B. Morley, R. J. Kurtz, L. L. Snead, and N. M. Ghoniem, "Development of Advanced Blanket Performance under Irradiation and System Integration through Jupiter-Ii Project," Fusion Engineering and Design 83, 842-849 (2008). D. L. Abernathy "ARCS: a wide Angular-Range Chopper Spectrometer at the SNS," Notiziario Neutroni e Luce di Sincrotrone 13, 4 (2008).

84

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

85

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

86

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

87

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

88

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

89

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

90

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. ...

91

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...

92

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

93

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...

94

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

95

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

96

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

97

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

98

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.

99

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

100

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

Note: This page contains sample records for the topic "angular-range chopper 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

com  

Science Conference Proceedings (OSTI)

... technique and performed both elastic and inelastic neutron scattering measurements using triple-axis and cold-chopper spectrometers at ORNL. ...

102

Dr. Garrett E. Granroth | ORNL Neutron Sciences  

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

Lead Instrument Scientist: Fine-Resolution Fermi Chopper Spectrometer (SEQUOIA), SNS Education PhD in Condensed Matter and Ultra-Low Temperature Physics, University of...

103

Tandem photonic-crystal thin films surpassing Lambertian light-trapping limit over broad bandwidth and angular range  

E-Print Network (OSTI)

The maximum absorption of solar radiation over the broadest range of frequencies and incident angles using the thinnest material possible has important applications for renewable-energy generation. Complete random texturing of an optically-thick film's surface to increase the path length of scattered light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Recent thin-film nanostructured designs involving resonant wave effects of photons have explored the possibility of superior performance though as of yet no proposal satisfying the dual requirements of enhanced and robust absorption over a large fraction of the solar spectrum has been made. Here using recent advances in computational electrodynamics we describe a general strategy for the design of a silicon thin film applicable to photovoltaic cells based on a quasi-resonant approach to light trapping where two partially-disordered photonic-crystal slabs, s...

Oskooi, Ardavan; Noda, Susumu

2013-01-01T23:59:59.000Z

104

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

105

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

106

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

107

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

108

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

109

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

110

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

111

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

112

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

113

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

114

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

115

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

116

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

117

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

118

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

119

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

120

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

Note: This page contains sample records for the topic "angular-range chopper 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

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

122

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

123

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

124

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

125

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

126

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

127

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

128

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

129

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

130

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

131

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

132

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

133

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

134

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

135

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

136

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

137

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

138

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

139

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.

140

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

Note: This page contains sample records for the topic "angular-range chopper spectrometer" from the National Library of EnergyBeta (NLEBeta).
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141

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

142

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

143

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

144

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

145

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

146

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

147

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

148

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

149

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

150

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

151

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

152

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

153

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

154

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

155

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

156

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

157

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

158

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

159

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

160

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

Note: This page contains sample records for the topic "angular-range chopper 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

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

162

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

163

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

164

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

165

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

166

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

167

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

168

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

169

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

170

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

171

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

172

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

173

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

174

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

175

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

176

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

177

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

178

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

179

CNCS Media Gallery | ORNL Neutron Sciences  

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

Module Detector tube testing module. Frame Overlap Chopper Frame overlap chopper. 16 Tesla Magnet. Fermi Chopper Fermi chopper. High Speed Double Disk Chopper High-speed double...

180

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

Note: This page contains sample records for the topic "angular-range chopper 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.


181

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

182

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

183

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

184

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

185

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

186

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

187

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

188

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

189

Dr. Andrey Podlesnyak | ORNL Neutron Sciences  

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

Andrey Podlesnyak Andrey Podlesnyak Dr. Andrey Podlesnyak Instrument Scientist: Cold Neutron Chopper Spectrometer (CNCS), SNS Education PhD in Physics, Institute for Metal Physics, Ekaterinburg, Russia Description of Research 2008 - present Instrument Scientist, Cold Neutron Chopper Spectrometer, Neutron Scattering Sciences Division, Oak Ridge National Laboratory 2006 - 2008 Instrument Scientist, single crystal diffractometer E-4, Hahn-Meitner-Institut, Berlin, Germany 2002 - 2006 Instrument Scientist, TOF spectrometer FOCUS, Laboratory for Neutron Scattering, ETH Zurich & Paul Scherrer Institute, Switzerland 2000 - 2002 Instrument Scientist, triple-axis spectrometer TASP, Laboratory for Neutron Scattering, ETH Zurich & Paul Scherrer Institute, Switzerland 1994 - 2000 Physicist, Institute for Metal Physics, Ekaterinburg, Russia

190

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

191

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

192

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

193

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

194

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

195

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

196

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

197

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

198

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

199

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

200

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

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201

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

202

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

203

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

204

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

205

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

206

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

207

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

208

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

209

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

210

A small diameter, flexible, all attitude, self-contained germanium spectrometer. Operator`s manual  

SciTech Connect

The end of the Cold War has brought about tremendous changes in the nuclear complex of the Department of Energy. One of the many changes has been the shutdown or decommissioning of many facilities that performed nuclear work. One of the steps in the process of decommissioning a facility involves the decontamination or removal of drain lines or pipes that may have carried radioactive materials at one time. The removal of all these pipes and drain lines to a nuclear disposal facility could be quite costly. It was suggested by Pacific Northwest National Laboratory (PNNL) that a germanium spectrometer could be built that could fit through straight pipes with a diameter as small as 5.08 cm (2 inches) and pass through curved pipes with a diameter as small as 7.6 cm (3 inches) such as that of a 3-inch p-trap in a drain line. The germanium spectrometer could then be used to simultaneously determine all gamma-ray emitting radionuclides in or surrounding the pipe. By showing the absence of any gamma-ray emitting radionuclides, the pipes could then be reused in place or disposed of as non-radioactive material, thus saving significantly in disposal costs. A germanium spectrometer system has been designed by PNNL and fabricated by Princeton Gamma Tech (PGT) that consists of three segments, each 4.84 cm in diameter and about 10 cm in length. Flexible stainless steel bellows were used to connect the segments. Segment 1 is a small liquid nitrogen reservoir. The reservoir is filled with a sponge-like material which enables the detector to be used in any orientation. A Stirling cycle refrigerator is under development which can replace the liquid nitrogen reservoir to provide continuous cooling and operation.

Bordzindki, R.L.; Lepel, E.A.; Reeves, J.H. [Battelle, Pacific Northwest National Lab., Richland, WA (United States); Kohli, R. [Battelle, Columbus Lab., OH (United States)

1997-05-01T23:59:59.000Z

211

High-resolution x-ray spectroscopy with the EBIT Calorimeter Spectrometer  

Science Conference Proceedings (OSTI)

The EBIT Calorimeter Spectrometer (ECS) is a production-class 36 pixel x-ray calorimeter spectrometer that has been continuously operating at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory for almost 2 years. The ECS was designed to be a long-lifetime, turn-key spectrometer that couples high performance with ease of operation and minimal operator intervention. To this end, a variant of the Suzaku/XRS spaceflight detector system has been coupled to a low-maintenance cryogenic system consisting of a long-lifetime liquid He cryostat, and a closed cycle, {sup 3}He pre-cooled adiabatic demagnetization refrigerator. The ECS operates for almost 3 weeks between cryogenic servicing and the ADR operates at 0.05 K for more than 60 hours between automatic recycles under software control. Half of the ECS semiconductor detector array is populated with mid-band pixels that have a resolution of 4.5 eV FWHM, a bandpass from 0.05-12 keV, and a quantum efficiency of 95% at 6 keV. The other half of the array has thick HgTe absorbers that have a bandpass from 0.3 to over 100 keV, an energy resolution of 33 eV FWHM, and a quantum efficiency of 32% at 60 keV. In addition, the ECS uses a real-time, autonomous, data collection and analysis system developed for the Suzaku/XRS instrument and implemented in off-the-shelf hardware for the ECS. Here we will discuss the performance of the ECS instrument and its implementation as a turnkey cryogenic detector system.

Porter, F S; Adams, J S; Beiersdorfer, P; Brown, G V; Clementson, J; Frankel, M; Kahn, S M; Kelley, R L; Kilbourne, C A

2009-10-01T23:59:59.000Z

212

High Energy Photoemission: Development of a New Electrostatic Lens for a Novel High Resolution Spectrometer  

SciTech Connect

In recent years growing interest has been dedicated to photoemission experiments at high energy because a significant bulk sensitivity in photoemission measurements can be achieved only by increasing the kinetic energy of the analysed photoelectrons. Within the 5th European framework, a RTD project named VOLPE (VOLume PhotoEmission from solids) has been funded. Aim of the project is to measure bulk electronic properties on solids by the Photoemission Spectroscopy with Synchrotron Radiation preserving an energy resolution comparable to modern surface sensitive photoemission spectra. This will be possible by performing photoemission experiments in a photolectron Kinetic Energy range of 6-10 keV, keeping the overall energy resolution at 20-30 meV. Presently, the beamline ID16 at ESRF posses the necessary characteristics (1011 photons/sec and 15-100 meV resolution at photon energies between 6 keV and 15 keV) to perform these class of experiments, while a new spectrometer is being developed in the framework of VOLPE project. This spectrometer is an hemispherical deflector analyser with electrostatic input lens and 2D position sensitive detector. The spectrometer will be characterised by an ultimate resolving power of 3 105 at 10 keV. We will report on the particular lens system developed for this project which is optimised to guarantee very high retarding ratio, between 50 and 600, with constant linear magnification. A prototype of this lens has been realised and we will report on the first measurements performed at INFM, Unita Roma Tre.

Paolicelli, G.; Fondacaro, A.; Offi, F. [INFM, Unita Roma Tre, Via della Vasca Navale 84 -I 00146 Rome (Italy); Stefani, G. [INFM, Unita Roma Tre, Via della Vasca Navale 84 -I 00146 Rome (Italy); Dip. di Fisica 'E. Amaldi', Universita Roma Tre Via della Vasca Navale 84-I 00146 Rome (Italy)

2004-05-12T23:59:59.000Z

213

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

214

Spectroscopic Investigations of Highly Charged Ions using X-Ray Calorimeter Spectrometers  

Science Conference Proceedings (OSTI)

Spectroscopy of K-shell transitions in highly charged heavy ions, like hydrogen-like uranium, has the potential to yield information about quantum electrodynamics (QED) in extremely strong nuclear fields as well as tests of the standard model, specifically parity violation in atomic systems. These measurements would represent the 'holy grail' in high-Z atomic spectroscopy. However, the current state-of-the-art detection schemes used for recording the K-shell spectra from highly charged heavy ions does not yet have the resolving power to be able to attain this goal. As such, to push the field of high-Z spectroscopy forward, new detectors must be found. Recently, x-ray calorimeter spectrometers have been developed that promise to make such measurements. In an effort to make the first steps towards attaining the 'holy grail', measurements have been performed with two x-ray calorimeter spectrometers (the XRS/EBIT and the ECS) designed and built at Goddard Space Flight Center in Greenbelt, MD. The calorimeter spectrometers have been used to record the K-shell spectra of highly charged ions produced in the SuperEBIT electron beam ion trap at Lawrence Livermore National Laboratory in Livermore, CA. Measurements performed with the XRS/EBIT calorimeter array found that the theoretical description of well-above threshold electron-impact excitation cross sections for hydrogen-like iron and nickel ions are correct. Furthermore, the first high-resolution spectrum of hydrogen-like through carbon-like praseodymium ions was recorded with a calorimeter. In addition, the new high-energy array on the EBIT Calorimeter Spectrometer (ECS) was used to resolve the K-shell x-ray emission spectrum of highly charged xenon ions, where a 40 ppm measurement of the energy of the K-shell resonance transition in helium-like xenon was achieved. This is the highest precision result, ever, for an element with such high atomic number. In addition, a first-of-its-kind measurement of the effect of the generalized Breit interaction (GBI) on electron-impact excitation cross sections was performed. This measurement found that for theoretical electron-impact excitation cross sections to fit with experimental data the GBI needs to be taken into account.

Thorn, D B

2008-11-03T23:59:59.000Z

215

Temperature Profile of IR Blocking Windows Used in Cryogenic X-Ray Spectrometers  

SciTech Connect

Cryogenic high-resolution X-ray spectrometers are typically operated with thin IR blocking windows to reduce radiative heating of the detector while allowing good x-ray transmission. We have estimated the temperature profile of these IR blocking windows under typical operating conditions. We show that the temperature in the center of the window is raised due to radiation from the higher temperature stages. This can increase the infrared photon flux onto the detector, thereby increasing the IR noise and decreasing the cryostat hold time. The increased window temperature constrains the maximum window size and the number of windows required. We discuss the consequences for IR blocking window design.

Friedrich, S.; Funk, T.; Drury, O.; Labov, S.E.

2000-08-08T23:59:59.000Z

216

Atomic hydrogen density measurements in an ion source plasma using a vacuum ultraviolet absorption spectrometer  

DOE Green Energy (OSTI)

A system to determine the density and temperature of ground state hydrogen atoms in a plasma by vacuum ultraviolet laser absorption spectroscopy is described. The continuous tunability of the spectrometer allows for analysis at any of the Lyman transitions. The narrow bandwidth of the laser system allows for the accurate determination of the absorption lineshape and hence the translational temperature. The utility of the system is exemplified by data obtained on an ion-source plasma. The measurements demonstrate the quality of the data as well as illustrating the behavior of this ion source under varying discharge conditions. 9 refs., 5 figs., 1 tab.

Stutzin, G.C.; Young, A.T.; Schlachter, A.S.; Stearns, J.W.; Leung, K.N.; Kunkel, W.B.; Worth, G.T.; Stevens, R.R.

1989-01-01T23:59:59.000Z

217

The development of high performance online tracker for High Level Trigger of Muon Spectrometer of ALICE  

E-Print Network (OSTI)

The Muon Spectrometer (MS) of the ALICE experiment at LHC is equipped with a HLT (High Level Trigger), whose aim is to improve the accuracy of the trigger cuts delivered at the L0 stage. A computational challenge of real-time event reconstruction is satisfied to achieve this software trigger cut of the HLT. After the description of the online algorithms, the performance of the online tracker is compared with that of the offline tracker using the measured pp collisions at $\\sqrt{s}=7$ TeV.

Indranil Das

2011-05-19T23:59:59.000Z

218

The development of high performance online tracker for High Level Trigger of Muon Spectrometer of ALICE  

E-Print Network (OSTI)

The Muon Spectrometer (MS) of the ALICE experiment at LHC is equipped with a HLT (High Level Trigger), whose aim is to improve the accuracy of the trigger cuts delivered at the L0 stage. A computational challenge of real-time event reconstruction is satisfied to achieve this software trigger cut of the HLT. After the description of the online algorithms, the performance of the online tracker is compared with that of the offline tracker using the measured pp collisions at $\\sqrt{s}=7$ TeV.

Das, Indranil

2011-01-01T23:59:59.000Z

219

A co-axially configured submillimeter spectrometer and investigations of hydrogen bound molecular complexes  

E-Print Network (OSTI)

The development of a co-axially configured submillimeter spectrometer is reported. The spectrometer has been constructed to observe molecular complexes that exhibit non-covalent interactions with energies much less than that of a traditional covalent bond. The structure of molecular complexes such as those formed between a rare gas and a hydrogen halide, Rg:HX where Rg is a rare gas (Rg=Ne, Ar and Kr) and HX (X=F, Cl, Br and I) can be determined directly and accurately. The center of mass interaction distance, RCM, as well as the angle of the hydrogen halide is determined, along with direct evaluation of the intermolecular vibrations as well as accurate isomerization energies between the hydrogen bound and van der Waals forms. The accuracy of the frequency determination of rovibrational transitions using the submillimeter spectrometer is also evaluated by direct comparison with the state-of-theart pulsed nozzle Fourier transform microwave spectrometer, and this accuracy is estimated to be less than 1 kHz at 300 GHz. The tunneling or geared bending vibration of a dimer of hydrogen bromide or hydrogen iodide has been investigated. The selection rules, nuclear statistics and intensity alternation for transitions observed in these dimmers, which is a consequence of interchanging two identical nuclei in the low frequency geared bending vibration of the molecular complex, are reported. Furthermore, the rotation and quadrupole coupling constants are used to determine a vibrationally averaged structure of the complex. The energy of the low frequency bending vibration can then be compared with ab initio based potential energy surfaces. A study of the multiple isomeric forms of the molecular complex OC:HI is also presented. Multiple isotopic substitutions are used to determine the relevant ground state structures and data reported evidence for an anomalous isotope effect supporting a ground state isotopic isomerization effect. All spectroscopic data that has been reported here has been additionally used to subsequently model and generate vibrationally complete morphed potential energy surfaces that are capable or reproducing the experimentally observed data. The utility of this procedure is evaluated on a predicative basis and comparisons made with newly observed data.

McElmurry, Blake Anthony

2008-12-01T23:59:59.000Z

220

Dr. Georg Ehlers - ORNL Neutron Sciences  

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

Georg Ehlers Georg Ehlers Lead Instrument Scientist: Cold Neutron Chopper Spectrometer (CNCS), SNS Education PhD in Experimental Condensed Matter Physics, the Hahn Meitner Institut, in Berlin, Germany Description of Research Dr. Ehlers joined the Spallation Neutron Source (SNS) in 2003 as the lead instrument scientist for beam line 5, the Cold Neutron Chopper Spectrometer (CNCS). CNCS is a high-resolution, direct geometry, cold neutron, inelastic multi-chopper spectrometer, designed to make use of neutrons with an energy of <50 meV. Before joining the SNS, Dr. Ehlers worked at the Institute Laue-Langevin (ILL), a leading European neutron research facility situated in Grenoble, France for six years. At the ILL, he was instrument-responsible for the spin-echo spectrometers IN11 and IN15, and established a strong research

Note: This page contains sample records for the topic "angular-range chopper 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

Application of a trochoidal electron monochromator/mass spectrometer system to the study of environmental chemicals  

SciTech Connect

A trochoidal electron monochromator has been interfaced to a mass spectrometer to perform electron capture negative ion mass spectrometric (ECNIMS) analyses of environmentally relevant chemicals. The kinetic energy of the electron beam can be varied from 0.025 to 30 eV under computer control. No reagent gas is used to moderate the electron energies. An electron energy spread of +/- 0.1 to +/- 0.4 eV full width at half-maximum (fwhm) can readily be obtained at a transmitted current of 2 x 10(-6) A, improving to +/- 0.07 eV at 5 x 10(-7) A. Comparisons of ECNI results from the electron monochromator/mass spectrometer system with those from a standard instrument that uses a moderating gas show similar spectra for heptachlor but not for the s-triazine herbicides, as for example, atrazine. This compound shows numerous adduct ions by standard ECNIMS that are eliminated by using the electron monochromator to generate the mass spectra. Isomeric tetrachlorodibenzo-p-dioxins show distinct differences in the electron energies needed to produce the maximum amount of parent and fragment anions. Multiple resonance states resulting in stable radical anions (M.-) are easily observed for nitrobenzene and for polycyclic aromatic hydrocarbons. Ionic products of dissociative electron capture invariably occur from several resonance states.

Laramee, J.A.; Kocher, C.A.; Deinzer, M.L. (Oregon State Univ., Corvallis (United States))

1992-10-15T23:59:59.000Z

222

Evaluation of dead time and gain shift correction for a liquid scintillation spectrometer  

SciTech Connect

The Department of Nuclear Engineering at Texas A and M University purchased a new generation liquid scintillation spectrometer--the LKB-Wallac Spectral Model 1219 in 1986. The Model 1219 features an auto sample changer with a capacity for 300 samples, and energy range of 1 to 2000 keV beta subdivided into 1024 channels, a Ra-226 external quench-correction standard, automatic dead time correction, and LED display of the beta energy spectrum. Gain stabilization is based on the use of a precision pulsed light-emitting diode (LED). The instrument's circuitry monitors the pulse height of the light emitted by the LED and adjusted the system gain as necessary to keep the LED-induced pulses constant, thus compensating for gain shifts. This paper reports that a simple test was devised to evaluate this liquid scintillation spectrometer's dead time correction and gain stabilization features. At the same time, the effectiveness of the counting chamber shielding was also tested for a specific situation.

McLain, M.E.; Grimes, M.J.; Lee, P.J.T. (Dept. of Nuclear Engineering, Texas A and M Univ., College Station, TX (US))

1987-09-01T23:59:59.000Z

223

Detection Efficiency of a ToF Spectrometer from Heavy-Ion Elastic Recoil Detection  

SciTech Connect

The detection efficiency of a time-of-flight system based on two micro-channel plates (MCP) time zero detectors plus a conventional silicon surface barrier detector was obtained from heavy ion elastic recoil measurements (this ToF spectrometer is mainly devoted to measurements of total fusion cross section of weakly bound projectiles on different mass-targets systems). In this work we have used beams of {sup 7}Li, {sup 16}O, {sup 32}S and {sup 35}Cl to study the mass region of interest for its application to measurements fusion cross sections in the {sup 6,7}Li+{sup 27}Al systems at energies around and above the Coulomb barrier (0.8V{sub B{<=}}E{<=}2.0V{sub B}). As the efficiency of a ToF spectrometer is strongly dependent on the energy and mass of the detected particles, we have covered a wide range of the scattered particle energies with a high degree of accuracy at the lowest energies. The different experimental efficiency curves obtained in that way were compared with theoretical electronic stopping power curves on carbon foils and were applied.

Barbara, E. de; Marti, G. V.; Capurro, O. A.; Fimiani, L.; Mingolla, M. G. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); Negri, A. E.; Arazi, A.; Figueira, J. M.; Pacheco, A. J.; Martinez Heimann, D.; Carnelli, P. F. F. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); CONICET, Av. Rivadavia 1917, C1033AAJ Ciudad Autonoma de Buenos Aires (Argentina); Fernandez Niello, J. O. [Laboratorio ANDAR, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, B1650KNA Partido de San Martin, Provincia de Buenos Aires (Argentina); CONICET, Av. Rivadavia 1917, C1033AAJ Ciudad Autonoma de Buenos Aires (Argentina); Universidad Nacional de General San Martin, Ayacucho 2197, B1650BWA Partido de San Martin, Provincia de Buenos Aires (Argentina)

2010-08-04T23:59:59.000Z

224

A high resolution gamma-ray spectrometer based on superconducting microcalorimeters  

SciTech Connect

Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gamma-ray microcalorimeters, based on transition-edge sensors (TESs), possible. At these collecting areas, gamma microcalorimeters can utilize their unprecedented energy resolution to perform spectroscopy in a number of applications that are limited by closely-spaced spectral peaks, for example, the nondestructive analysis of nuclear materials. We have built a 256 pixel spectrometer with an average full-width-at-half-maximum energy resolution of 53 eV at 97 keV, a useable dynamic range above 400 keV, and a collecting area of 5 cm{sup 2}. We have demonstrated multiplexed readout of the full 256 pixel array with 236 of the pixels (91%) giving spectroscopic data. This is the largest multiplexed array of TES microcalorimeters to date. This paper will review the spectrometer, highlighting the instrument design, detector fabrication, readout, operation of the instrument, and data processing. Further, we describe the characterization and performance of the newest 256 pixel array.

Bennett, D. A.; Horansky, R. D. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); University of Denver, Denver, Colorado 80208 (United States); Schmidt, D. R.; Doriese, W. B.; Fowler, J. W.; Kotsubo, V.; Mates, J. A. B. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); University of Colorado, Boulder, Colorado 80309 (United States); Hoover, A. S.; Winkler, R.; Rabin, M. W. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Alpert, B. K.; Beall, J. A.; Fitzgerald, C. P.; Hilton, G. C.; Irwin, K. D.; O'Neil, G. C.; Reintsema, C. D.; Schima, F. J.; Swetz, D. S.; Vale, L. R. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); and others

2012-09-15T23:59:59.000Z

225

A New Control System Software for SANS BATAN Spectrometer in Serpong, Indonesia  

Science Conference Proceedings (OSTI)

The original main control system of the 36 meter small-angle neutron scattering (SANS) BATAN Spectrometer (SMARTer) has been replaced with the new ones due to the malfunction of the main computer. For that reason, a new control system software for handling all the control systems was also developed in order to put the spectrometer back in operation. The developed software is able to control the system such as rotation movement of six pinholes system, vertical movement of four neutron guide system with the total length of 16.5 m, two-directional movement of a neutron beam stopper, forward-backward movement of a 2D position sensitive detector (2D-PSD) along 16.7 m, etc. A Visual Basic language program running on Windows operating system was employed to develop the software and it can be operated by other remote computers in the local area network. All device positions and command menu are displayed graphically in the main monitor or window and each device control can be executed by clicking the control button. Those advantages are necessary required for developing a new user-friendly control system software. Finally, the new software has been tested for handling a complete SANS experiment and it works properly.

Bharoto; Putra, Edy Giri Rachman [Neutron Scattering Laboratory, Center for Technology of Nuclear Industrial Materials, National Nuclear Energy Agency of Indonesia (BATAN) Gedung 40, Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia)

2010-06-22T23:59:59.000Z

226

Flat Quartz-Crystal X-ray Spectrometer for Nuclear Forensics Applications  

E-Print Network (OSTI)

The ability to quickly and accurately quantify the plutonium (Pu) content in pressurized water reactor (PWR) spent nuclear fuel (SNF) is critical for nuclear forensics purposes. One non-destructive assay (NDA) technique being investigated to detect bulk Pu in SNF is measuring the self-induced x-ray fluorescence (XRF). Previous XRF measurements of Three Mile Island (TMI) PWR SNF taken in July 2008 and January 2009 at Oak Ridge National Laboratory (ORNL) successfully illustrated the ability to detect the 103.7 keV x ray from Pu using a planar high-purity germanium (HPGe) detector. This allows for a direct measurement of Pu in SNF. Additional gamma ray and XRF measurements were performed on TMI SNF at ORNL in October 2011 to measure the signal-to-noise ratio for the 103.7 keV peak. Previous work had shown that the Pu/U peak ratio was directly proportional to the Pu/U content and increased linearly with burnup. However, the underlying Compton background significantly reduced the signal-to-noise ratio for the x-ray peaks of interest thereby requiring a prolonged count time. Comprehensive SNF simulations by Stafford et al showed the contributions to the Compton continuum were due to high-energy gamma rays scattering in the fuel, shipping tube, cladding, collimator and detector1. The background radiation was primarily due to the incoherent scattering of the 137Cs 661.7 keV gamma. In this work methods to reduce the Compton background and thereby increase the signal-to-noise ratio were investigated. To reduce the debilitating effects of the Compton background, a crystal x-ray spectrometer system was designed. This wavelength-dispersive spectroscopy technique isolated the Pu and U x rays according to Bragg's law by x-ray diffraction through a crystal structure. The higher energy background radiation was blocked from reaching the detector using a customized collimator and shielding system. A flat quartz-crystal x-ray spectrometer system was designed specifically to fit the constraints and requirements of detecting XRF from SNF. Simulations were performed to design and optimize the collimator design and to quantify the improved signal-to-noise ratio of the Pu and U x-ray peaks. The proposed crystal spectrometer system successfully diffracted the photon energies of interest while blocking the high-energy radiation from reaching the detector and contributing to background counts. The spectrometer system provided a higher signal-to-noise ratio and lower percent error for the XRF peaks of interest from Pu and U. Using the flat quartz-crystal x-ray spectrometer and customized collimation system, the Monte Carlo N-Particle (MCNP) simulations showed the 103.7 keV Pu x-ray peak signal-to-noise ratio improved by a factor of 13 and decreased the percent error by a factor of 3.3.

Goodsell, Alison

2012-08-01T23:59:59.000Z

227

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

228

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

229

The Road to Ultrahigh-Resolution X-ray Spectrometers | Advanced Photon  

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

How Atoms Behave: Characteristics of Microstructural Avalanches How Atoms Behave: Characteristics of Microstructural Avalanches Iodate Refuses to Intimidate Creating the Heart of a Planet in the Heart of a Gem How a Powerful Antibody Neutralizes HIV Taking a Page from Nature to Build Better Nanomaterials Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed The Road to Ultrahigh-Resolution X-ray Spectrometers NOVEMBER 22, 2011 Bookmark and Share Basic phenomena underlying the AD&AT x-ray optics. In x-ray Bragg diffraction from atomic planes composing nonzero angle η to the crystal entrance face, the crystal acts (a) like an optical prism dispersing the photons into a divergent x-ray fan with photons of different energies E

230

Manifold and method of batch measurement of Hg-196 concentration using a mass spectrometer  

DOE Patents (OSTI)

A sample manifold and method of its use has been developed so that milligram quantities of mercury can be analyzed mass spectroscopically to determine the [sup 196]Hg concentration to less than 0.02 atomic percent. Using natural mercury as a standard, accuracy of [+-]0.002 atomic percent can be obtained. The mass spectrometer preferably used is a commercially available GC/MS manufactured by Hewlett Packard. A novel sample manifold is contained within an oven allowing flow rate control of Hg into the MS. Another part of the manifold connects to an auxiliary pumping system which facilitates rapid clean up of residual Hg in the manifold. Sample cycle time is about 1 hour. 8 figures.

Grossman, M.W.; Evans, R.

1991-11-26T23:59:59.000Z

231

Total Ozone Mapping Spectrometer (TOMS) Derived Data, Global Earth Coverage (GEC) from NASA's Earth Probe Satellite  

DOE Data Explorer (OSTI)

This is data from an external datastream processed through the ARM External Data Center (XDC) at Brookhaven National Laboratory. The XDC identifies sources and acquires data, called "external data", to augment the data being generated within the ARM program. The external data acquired are usually converted from native format to either netCDF or HDF formats. The GEC collection contains global data derived from the Total Ozone Mapping Spectrometer (TOMS) instrument on the Earth Probe satellite, consisting of daily values of aerosol index, ozone and reflectivity remapped into a regular 1x1.25 deg grid. Data are available from July 25, 1996 - December 31, 2005, but have been updated or replaced as of September 2007. See the explanation on the ARM web site at http://www.arm.gov/xds/static/toms.stm and the information at the NASA/TOMS web site: http://toms.gsfc.nasa.gov/ (Registration required)

232

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

233

A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility  

SciTech Connect

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors (GXD) it records sixteen time-gated spectra between 250 and 1000eV with 100ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and VUV beamline at the National Synchrotron Light Source (NSLS), evidence a <100{micro}m spatial resolution in combination with a source-size limited spectral resolution that is <10eV at photon energies of 300eV.

Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

2012-05-01T23:59:59.000Z

234

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

235

Grazing incidence extreme ultraviolet spectrometer fielded with time resolution in a hostile Z-pinch environment  

Science Conference Proceedings (OSTI)

This recently developed diagnostic was designed to allow for time-gated spectroscopic study of the EUV radiation (4 nm power generator (1 MA, 100 ns risetime) at University of Nevada, Reno on a series of wire array z-pinch loads. Within this harsh z-pinch environment, radiation yields routinely exceed 20 kJ in the EUV and soft x-ray. There are also strong mechanical shocks, high velocity debris, sudden vacuum changes during operation, energic ion beams, and hard x-ray radiation in excess of 50 keV. The spectra obtained from the precursor plasma of an Al double planar wire array contained lines of Al IX and AlX ions indicating a temperature near 60 eV during precursor formation. Detailed results will be presented showing the fielding specifications and the techniques used to extract important plasma parameters using this spectrometer.

Williamson, K. M.; Kantsyrev, V. L.; Safronova, A. S.; Wilcox, P. G.; Cline, W.; Batie, S.; LeGalloudec, B.; Nalajala, V.; Astanovitsky, A. [Plasma Physics and Diagnostics Laboratory, Physics Department, University of Nevada, Reno, Nevada 89557 (United States)

2011-09-15T23:59:59.000Z

236

IBIS: An inverse geometry Brillouin inelastic neutron spectrometer for the SNS  

Science Conference Proceedings (OSTI)

The high power target station at the Spallation Neutron Source (SNS) currently has about 20 completed neutron scattering instruments. With a broad coverage of the momentum transfer (Q)-energy (E) space, these instruments serve an extensive user community. In an effort to further expand the scientific capabilities of the SNS instrument suites, we propose a low background, inverse geometry Brillouin inelastic spectrometer for the SNS which will expand the Q-E coverage of the current instrument suite and facilitate the study of inelastic and quasi-elastic scatterings at low Q values. The possible location for the proposed instrument is either beamline 8 which views the decoupled water moderator, or beamline 14A, which views a cold, coupled super critical hydrogen moderator. The instrument parameters, optimizations, and performances at these two beamline locations are discussed.

Zhao, Jinkui [ORNL; Wildgruber, Christoph U [ORNL; Robertson, Lee [ORNL; Herwig, Kenneth W [ORNL

2013-01-01T23:59:59.000Z

237

A Dual Channel X-ray Spectrometer for Fast Ignition Research  

SciTech Connect

A new Dual Channel Highly Ordered Pyrolytic Graphite (DC-HOPG) x-ray spectrometer was developed to study laser-generated electron beam transport. The instrument uses a pair of graphite crystals and has the advantage of simultaneously detecting self emission from low-Z materials in first diffraction order and high-Z materials in second order. The emissions from the target are detected using a pair of parallel imaging plates positioned in a such way that the noise from background is minimized and the mosaic focusing is achieved. Initial tests of the diagnostic on Titan laser (I {approx} 10{sup 20} W/cm{sup 2}, {tau} = 0.7 ps) show excellent signal-to-noise ratio (SNR) > 1000 for the low energy channel and SNR > 400 for the high energy channel.

Akli, K U; Patel, P K; Van Maren, R; Stephens, R B; Key, M H; Higginson, D P; Westover, B; Chen, C D; Mackinnon, A J; Bartal, T; Beg, F N; Chawla, S; Fedosejevs, R; Freeman, R R; Hey, D S; Kemp, G E; LePape, S; Link, A; Ma, T; MacPhee, A G; McLean, H S; Ping, Y; Tsui, Y Y; Van Woerkom, L D; Wei, M S; Yabuuchi, T

2010-04-19T23:59:59.000Z

238

System for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high (n,f) reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

Fries, D.P.; Browning, J.F.

1998-07-21T23:59:59.000Z

239

System for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

Fries, David P. (St. Petersburg, FL); Browning, James F. (Palm Harbour, FL)

1998-01-01T23:59:59.000Z

240

Method for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

Fries, David P. (St. Petersburg, FL); Browning, James F. (Palm Harbour, FL)

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

Method for studying a sample of material using a heavy ion induced mass spectrometer source  

DOE Patents (OSTI)

A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu. 3 figs.

Fries, D.P.; Browning, J.F.

1999-02-16T23:59:59.000Z

242

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) on the New Horizons Mission  

E-Print Network (OSTI)

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) comprises the hardware and accompanying science investigation on the New Horizons spacecraft to measure pick-up ions from Pluto's outgassing atmosphere. To the extent that Pluto retains its characteristics similar to those of a "heavy comet" as detected in stellar occultations since the early 1980s, these measurements will characterize the neutral atmosphere of Pluto while providing a consistency check on the atmospheric escape rate at the encounter epoch with that deduced from the atmospheric structure at lower altitudes by the ALICE, REX, and SWAP experiments on New Horizons. In addition, PEPSSI will characterize any extended ionosphere and solar wind interaction while also characterizing the energetic particle environment of Pluto, Charon, and their associated system. First proposed for development for the Pluto Express mission in September 1993, what became the PEPSSI instrument went through a number of development stages to meet the...

McNutt, Ralph L; Gurnee, Reid S; Hill, Matthew E; Cooper, Kim A; Andrews, G Bruce; Keath, Edwin P; Krimigis, Stamatios M; Mitchell, Donald G; Tossman, Barry; Bagenal, Fran; Boldt, John D; Bradley, Walter; Devereux, William S; Ho, George C; Jaskulek, Stephen E; LeFevere, Thomas W; Malcom, Horace; Marcus, Geoffrey A; Hayes, John R; Moore, G Ty; Williams, Bruce D; Wilson, Paul; Brown, L E; Kusterer, M; Vandegriff, J

2007-01-01T23:59:59.000Z

243

A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility  

SciTech Connect

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 {mu}m spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV.

Moore, A. S.; Guymer, T. M.; Morton, J.; Bentley, C.; Stevenson, M. [Directorate Science and Technology, AWE Aldermaston, Reading, RG7 4PR (United Kingdom); Kline, J. L.; Taccetti, M.; Lanier, N. E.; Workman, J.; Peterson, B.; Mussack, K.; Cowan, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Prasad, R.; Richardson, M.; Burns, S.; Kalantar, D. H.; Benedetti, L. R.; Bell, P.; Bradley, D.; Hsing, W. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States)

2012-10-15T23:59:59.000Z

244

Dual mode ion mobility spectrometer and method for ion mobility spectrometry  

DOE Patents (OSTI)

Ion mobility spectrometer apparatus may include an ion interface that is operable to hold positive and negative ions and to simultaneously release positive and negative ions through respective positive and negative ion ports. A first drift chamber is operatively associated with the positive ion port of the ion interface and encloses an electric field therein. A first ion detector operatively associated with the first drift chamber detects positive ions from the first drift chamber. A second drift chamber is operatively associated with the negative ion port of the ion interface and encloses an electric field therein. A second ion detector operatively associated with the second drift chamber detects negative ions from said second drift chamber.

Scott, Jill R [Idaho Falls, ID; Dahl, David A [Idaho Falls, ID; Miller, Carla J [Idaho Falls, ID; Tremblay, Paul L [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

2007-08-21T23:59:59.000Z

245

A New Bruker IFS 125HR FTIR Spectrometer for the Polar Environment Atmospheric Research Laboratory at Eureka, Nunavut, Canada: Measurements and Comparison with the Existing Bomem DA8 Spectrometer  

Science Conference Proceedings (OSTI)

A new Bruker IFS 125HR Fourier transform spectrometer has been installed at the Polar Environment Atmospheric Research Laboratory at Eureka, Nunavut, Canada (80.05°N, 86.42°W). This instrument will become the Network for the Detection of ...

Rebecca L. Batchelor; Kimberly Strong; Rodica Lindenmaier; Richard L. Mittermeier; Hans Fast; James R. Drummond; Pierre F. Fogal

2009-07-01T23:59:59.000Z

246

Streaked x-ray spectrometer having a discrete selection of Bragg geometries for Omega  

Science Conference Proceedings (OSTI)

The streaked x-ray spectrometer (SXS) is used with streak cameras [D. H. Kalantar, P. M. Bell, R. L. Costa, B. A. Hammel, O. L. Landen, T. J. Orzechowski, J. D. Hares, and A. K. L. Dymoke-Bradshaw, in 22nd International Congress on High-Speed Photography and Photonics, edited by D. L. Paisley and A. M. Frank (SPIE, Bellingham, WA, 1997), Vol. 2869, p. 680] positioned with a ten-inch manipulator on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] and OMEGA EP [L. J. Waxer et al., Presented at CLEO/QELS 2008, San Jose, CA, 4-9 May 2008 (Paper JThB1)] for time-resolved, x-ray spectroscopy of laser-produced plasmas in the 1.4- to 20-keV photon-energy range. These experiments require measuring a portion of this photon-energy range to monitor a particular emission or absorption feature of interest. The SXS relies on a pinned mechanical reference system to create a discrete set of Bragg reflection geometries for a variety of crystals. A wide selection of spectral windows is achieved accurately and efficiently using this technique. It replaces the previous spectrometer designs that had a continuous Bragg angle adjustment and required a tedious alignment calibration procedure. The number of spectral windows needed for the SXS was determined by studying the spectral ranges selected by OMEGA users over the last decade. These selections are easily configured in the SXS using one of the 25 discrete Bragg reflection geometries and one of the six types of Bragg crystals, including two curved crystals.

Millecchia, M.; Regan, S. P.; Bahr, R. E.; Romanofsky, M.; Sorce, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States)

2012-10-15T23:59:59.000Z

247

In situ multipurpose time-resolved spectrometer for monitoring nanoparticle generation in a high-pressure fluid  

Science Conference Proceedings (OSTI)

We developed a multipurpose time-resolved spectrometer for studying the dynamics of nanoparticles generated by pulsed-laser ablation (PLA) in a high-pressure fluid. The apparatus consists of a high-pressure optical cell and three spectrometers for in situ measurements. The optical cell was designed for experiments at temperatures up to 400 K and pressures up to 30 MPa with fluctuations within {+-}0.1% h{sup -1}. The three spectrometers were used for the following in situ measurements at high pressures: (i) transient absorption spectrum measurements from 350 to 850 nm to investigate the dynamics of nanoparticle generation from nanoseconds to milliseconds after laser irradiation, (ii) absorption spectrum measurements from 220 to 900 nm to observe the time evolution of nanoparticles from seconds to hours after laser ablation, and (iii) dynamic light scattering measurements to track nanoparticles with sizes from 10 nm to 10 {mu}m in the time range from seconds to hours after laser ablation. By combining these three spectrometers, we demonstrate in situ measurements of gold nanoparticles generated by PLA in supercritical fluids. This is the first report of in situ time-resolved measurements of the dynamics of nanoparticles generated in a supercritical fluid.

Wei, Shaoyu [Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, 739-8526 Higashi-hiroshima (Japan); Saitow, Ken-ichi [Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, 739-8526 Higashi-hiroshima (Japan); Natural Science Center for Basic Research and Development (N-BARD), 1-3-1 Kagamiyama, 739-8526 Higashi-hiroshima (Japan)

2012-07-15T23:59:59.000Z

248

LANSCE | Lujan Center | Instruments | PHAROS  

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

High-Resolution Chopper Spectrometer | Pharos High-Resolution Chopper Spectrometer | Pharos Local Structure, Magnetism, and Nanomaterials Pharos is designed for studies of fundamental excitations in condensed-matter systems. The instrument provides 2% to 4% incident energy resolution and uses a high-speed Fermi chopper to obtain monochromatic incident energies in the range from 10 meV to 2 eV. The sample is positioned 20 meters from a chilled-water moderator. The spectrometer consists of an evacuated, shielded flight path with 10 m2 of meter-long position-sensitive detectors located at a distance of 4 meters from the sample and covering scattering angles between -10° and 145°. Pharos can accommodate the full range of inelastic scattering experiments on liquid, polycrystalline, and single-crystal samples. This includes

249

X-Ray Emission Spectrometer Design with Single-Shot Pump-Probe and Resonant Excitation Capabilities  

Science Conference Proceedings (OSTI)

Core-level spectroscopy in the soft X-ray regime is a powerful tool for the study of chemical bonding processes. The ultrafast, ultrabright X-ray pulses generated by the Linac Coherent Light Source (LCLS) allow these reactions to be studied in greater detail than ever before. In this study, we investigated a conceptual design of a spectrometer for the LCLS with imaging in the non-dispersive direction. This would allow single-shot collection of X-ray emission spectroscopy (XES) measurements with varying laser pump X-ray probe delay or a variation of incoming X-ray energy over the illuminated area of the sample. Ray-tracing simulations were used to demonstrate how the components of the spectrometer affect its performance, allowing a determination of the optimal final design. These simulations showed that the spectrometer's non-dispersive focusing is extremely sensitive to the size of the sample footprint; the spectrometer is not able to image a footprint width larger than one millimeter with the required resolution. This is compatible with a single shot scheme that maps out the laser pump X-ray probe delay in the non-dispersive direction as well as resonant XES applications at normal incidence. However, the current capabilities of the Soft X-Ray (SXR) beamline at the LCLS do not produce the required energy range in a small enough sample footprint, hindering the single shot resonant XES application at SXR for chemical dynamics studies at surfaces. If an upgraded or future beamline at LCLS is developed with lower monochromator energy dispersion the width can be made small enough at the required energy range to be imaged by this spectrometer design.

Spoth, Katherine; /SUNY, Buffalo /SLAC

2012-08-28T23:59:59.000Z

250

A high etendue spectrometer suitable for core charge eXchange recombination spectroscopy on ITER  

SciTech Connect

A feasibility study for the use of core charge exchange recombination spectroscopy on ITER has shown that accurate measurements on the helium ash require a spectrometer with a high etendue of 1mm{sup 2}sr to comply with the measurement requirements [S. Tugarinov et al., Rev. Sci. Instrum. 74, 2075 (2003)]. To this purpose such an instrument has been developed consisting of three separate wavelength channels (to measure simultaneously He/Be, C/Ne, and H/D/T together with the Doppler shifted direct emission of the diagnostic neutral beam, the beam emission (BES) signal), combining high dispersion (0.02 nm/pixel), sufficient resolution (0.2 nm), high efficiency (55%), and extended wavelength range (14 nm) at high etendue. The combined measurement of the BES along the same sightline within a third wavelength range provides the possibility for in situ calibration of the charge eXchange recombination spectroscopy signals. In addition, the option is included to use the same instrument for measurements of the fast fluctuations of the beam emission intensity up to 2 MHz, with the aim to study MHD activity.

Jaspers, R. J. E.; Scheffer, M. [Science and Technology of Nuclear Fusion, Eindhoven University of Technology, Eindhoven (Netherlands); Kappatou, A. [FOM Institute DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Nieuwegein (Netherlands); Valk, N. C. J. van der; Durkut, M.; Snijders, B. [TNO Science and Industry, P.O. Box 155, 2600 AD Delft (Netherlands); Marchuk, O.; Biel, W. [Institut fuer Energie und Klimaforschung-IEK-4 Forschungszentrum, Juelich GmbH, 52425 Juelich (Germany); Pokol, G. I. [Institute of Nuclear Techniques, Budapest University of Technology and Economics, EURATOM Association, P. O. Box 91, H-1521 Budapest (Hungary); Erdei, G. [Department of Atomic Physics, Budapest University of Technology and Economics, EURATOM Association, P. O. Box 91, H-1521 Budapest (Hungary); Zoletnik, S.; Dunai, D. [WIGNER RCP, RMKI, EURATOM Association, P. O. Box 91, H-1521 Budapest (Hungary)

2012-10-15T23:59:59.000Z

251

Gamma-Ray Bursts Observed with the Spectrometer SPI Onboard INTEGRAL  

E-Print Network (OSTI)

The spectrometer SPI is one of the main detectors of ESA's INTEGRAL mission. The instrument offers two interesting and valuable capabilities for the detection of the prompt emission of Gamma-ray bursts. Within a field of view of 16 degrees, SPI is able to localize Gamma-ray bursts with an accuracy of 10 arcmin. The large anticoincidence shield, ACS, consisting of 512 kg of BGO crystals, detects Gamma-ray bursts quasi omnidirectionally above ~70 keV. Burst alerts from SPI/ACS are distributed to the interested community via the INTEGRAL Burst Alert System. The ACS data have been implemented into the 3rd Interplanetary Network and have proven valuable for the localization of bursts using the triangulation method. During the first 8 months of the mission approximately one Gamma-ray burst per month was localized within the field of fiew of SPI and 145 Gamma-ray burst candidates were detected by the ACS from which 40 % have been confirmed by other instruments.

A. von Kienlin; A. Rau; V. Beckmann; S. Deluit

2004-07-07T23:59:59.000Z

252

Airborne gamma-ray spectrometer and magnetometer survey, New Rockford Quadrangle, North Dakota. Final report  

Science Conference Proceedings (OSTI)

An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over eleven (11) 2/sup 0/ x 1/sup 0/ NTMS quadrangles located in the states of Minnesota and Wisconsin and seven (7) 2/sup 0/ x 1/sup 0/ NTMS quadrangles in North and South Dakota. The quadrangles located within the North and South Dakota survey area include Devil's Lake, New Rockford, Jamestown, Aberdeen, Huron, Mitchell, and Sioux Falls. This report discusses the results obtained over the New Rockford map area. Traverse lines were flown in an east-west direction at a line spacing of six (6) miles. Tie lines were flown north-south approximately twenty-four (24) miles apart. A total of 21,481 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 1397 line miles are in this quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.

Not Available

1981-04-01T23:59:59.000Z

253

Airborne gamma-ray spectrometer and magnetometer survey, Mitchell Quadrangle, South Dakota. Final report  

SciTech Connect

An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over eleven (11) 2/sup 0/ x 1/sup 0/ NTMS quadrangles located in the states of Minnesota and Wisconsin and seven (7) 2/sup 0/ x 1/sup 0/ NTMS quadrangles in North and South Dakota. The quadrangles located within the North and South Dakota survey area include Devil's Lake, New Rockford, Jamestown, Aberdeen, Huron, Mitchell, and Sioux Falls. This report discusses the results obtained over the Mitchell map area. The purpose of this program is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States. Traverse lines were flown in an east-west direction at a line spacing of six (6) miles. Tie lines were flown north-south approximately twenty-four (24) miles apart. A total of 21,481 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 1479 line miles are in this quadrangle.

Not Available

1981-04-01T23:59:59.000Z

254

Airborne gamma-ray spectrometer and magnetometer survey: Huron quadrangle, South Dakota. Final report  

Science Conference Proceedings (OSTI)

An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over eleven (11) 2/sup 0/ x 1/sup 0/ NTMS quadrangles located in the states of Minnesota and Wisconsin and seven (7) 2/sup 0/ x 1/sup 0/ NTMS quadrangles in North and South Dakota. The quadrangles located within the North and South Dakota survey area include Devil's Lake, New Rockford, Jamestown, Aberdeen, Huron, Mitchell, and Sioux Falls. This report discusses the results obtained over the Huron map area. Traverse lines were flown in an east-west direction at a line spacing of six (6) miles. Tie lines were flown north-south approximately twenty-four (24) miles apart. A total of 21,481 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 1459 line miles are in this quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.

Not Available

1981-04-01T23:59:59.000Z

255

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

256

Conditioning the gamma spectrometer for activity measurement at very high background  

E-Print Network (OSTI)

The application of a high purity germanium (HPGe) gamma spectrometer in determining the fuel element burnup in a future reactor is studied. The HPGe detector is exposed by a Co60 source with varying irradiation rate from 10 kcps to 150 kcps to simulate the input counting rate in real reactor environment. A Cs137 and a Eu152 source are positioned at given distances to generate certain event rate in the detector with the former being proposed as a labeling nuclide to measure the burnup of fuel element. It is shown that both the energy resolution slightly increasing with the irradiation rate and the passthrough rate at high irradiation level match the requirement of the real application. The influence of the background is studied in different parameter sets used in the particularly developed procedure of the background subtraction. It is demonstrated that with the typical input irradiation rate and Cs137 intensity relevant to deep burnup situation, the precision of the Cs137 counting rate in the current experiment is consistently below 2.8%, indicating a promising feasibility of utilizing an HPGe detector in the burnup measurement in future bed-like reactor.

Weihua Yan; Liguo Zhang; Zhao Zhang; Zhigang Xiao

2013-05-04T23:59:59.000Z

257

Hinode/Extreme-Ultraviolet Imaging Spectrometer Observations of the Temperature Structure of the Quiet Corona  

E-Print Network (OSTI)

We present a Differential Emission Measure (DEM) analysis of the quiet solar corona on disk using data obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on Hinode. We show that the expected quiet Sun DEM distribution can be recovered from judiciously selected lines, and that their average intensities can be reproduced to within 30%. We present a subset of these selected lines spanning the temperature range log T = 5.6 to 6.4 K that can be used to derive the DEM distribution reliably, including a subset of Iron lines that can be used to derive the DEM distribution free of the possibility of uncertainties in the elemental abundances. The subset can be used without the need for extensive measurements and the observed intensities can be reproduced to within the estimated uncertainty in the pre-launch calibration of EIS. Furthermore, using this subset, we also demonstrate that the quiet coronal DEM distribution can be recovered on size scales down to the spatial resolution of the instrument (1" pixels...

Brooks, David H; Williams, David R; Watanabe, Tetsuya

2009-01-01T23:59:59.000Z

258

Study of gas evolution during oil shale pyrolysis by TQMS (triple quadrupole mass spectrometer)  

DOE Green Energy (OSTI)

Real-time gas evolution during pyrolysis of two Green River Formation (Colorado) oil shales, one eastern US Devonian shale, and two Chinese shales was monitored using a triple quadrupole mass spectrometer (TQMS). We calculated kinetic parameters for hydrocarbon generation. For water, carbon oxides, and sulfur gases, we compared evolution profiles and identified the organicinorganic precursors of each species. We also monitored nitrogen- and sulfur-containing naphtha components. Hydrocarbon gas profiles, except for CH/sub 4/, are similar for all shales, and their rates of evolution reach a maximum at around the temperatures of maximum oil evolutions. The evolution profiles for H/sub 2/, CH/sub 2/, CO, and CO/sub 2/, at high temperatures are affected by the amount of char remaining in shale, carbonate minerals, and the water-gas shift reaction. The water profile, in general, consists of waters from surface dehydration, kerogen pyrolysis, and mineral dehydration. Mineral dehydration was the dominant water source for all shales, but the temperature ranges for the major water peak varied because of widely different mineral composition. Chinese shales evolved much more water than U.S. shales. Major differences between shales were seen in the sulfur gases. 17 refs., 4 figs., 3 tabs.

Oh, M.S.; Coburn, T.T.; Crawford, R.W.; Burnham, A.K.

1988-02-01T23:59:59.000Z

259

A technical review of the SWEPP gamma-ray spectrometer system  

Science Conference Proceedings (OSTI)

The SWEPP Gamma-ray Spectrometer (SGRS) was developed by INEL researchers as a nonintrusive method of determining the isotopic ratios of TRU and U materials in a 208-liter waste drums. The SGRS has been in use at SWEPP since mid-1994. Enough questions have been raised regarding the system reliability and technical capabilities, that, coupled with a desire to procure an additional gamma-ray spectroscopy system in order to increase the drum throughput of SWEPP, have prompted an independent technical review of the SGRS. The author was chosen as the reviewer, and this report documents the results of the review. While the SGRS is accurate in its isotopic ratio results, the system is not calculationally robust. The primary reason for this lack of calculational reliability is the implementation of the attenuation corrections. Suggested changes may improve the system reliability dramatically. The SGRS is a multiple detector spectrometry system. Tests were conducted on various methods for combining the four detector results into a single drum representative value. No clear solution was reached for the cases in which the isotopic ratios are vertically segregated; however, some methods showed promise. These should be investigated further. 14 refs. , 15 figs., 23 tabs.

Hartwell, J.K.

1996-03-01T23:59:59.000Z

260

Determining plasma-fueling sources with an end-loss ion spectrometer  

DOE Green Energy (OSTI)

To help identify the major sources of fueling gas in Tandem Mirror Experiment-Upgrade (TMX-U), we mounted a mass-sensitive, EVertical BarVertical BarB, end-loss ion spectrometer (ELIS) near the machine's centerline. We set the electric field in the ELIS to simultaneously measure the axial loss currents of both hydrogen and deuterium. We then initiated plasma discharges, where we injected either hydrogen or deuterium gas into the central cell. We also selected and deselected the central-cell neutral beams that were fueled with hydrogen gas. The end-cell neutral beams were always selected and fueled with deuterium. By taking the ratio of the hydrogen end-loss current to the deuterium end-loss current (with a known deuterium-gas feed rate), we were able to infer the effective fueling rates that were due to wall reflux, central-cell beams, and end-cell beams. The results were the following: wall reflux, 6 Torr l/s; central-cell beams, 15 Torr l/s; and end-cell beams 1 Torr l/s.

Grubb, D.P.; Foote, J.H.

1986-08-01T23:59:59.000Z

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261

Airborne gamma-ray spectrometer and magnetometer survey Coos Bay, Oregon. Final report  

Science Conference Proceedings (OSTI)

During the months of August, September, and October of 1980, Aero Service Division Western Geophysical Company of America conducted an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over ten (10) areas over northern California and southwestern Oregon. These include the 2/sup 0/ x 1/sup 0/ NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1/sup 0/ x 2/sup 0/ areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Coos Bay, Oregon, map area. Line spacing was generally six miles for east/west traverses and eighteen miles for north/south tie lines over the northern one-half of the area. Traverses and tie lines were flown at three miles and twelve miles respectively over the southern one-half of the area. A total of 16,880.5 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 863.8 line miles are in this quadrangle.

Not Available

1981-05-01T23:59:59.000Z

262

Airborne gamma-ray spectrometer and magnetometer survey, Medford Quadrangle Oregon. Final report  

Science Conference Proceedings (OSTI)

An airborne high sensitivity gamma-ray spectrometer and magnetometer survey was conducted over ten (10) areas over northern California and southwestern Oregon. These include the 2/sup 0/ x 1/sup 0/ NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1/sup 0/ x 2/sup 0/ areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Medford, Oregon, map area. Traverse lines were flown in an east-west direction at a line spacing of three miles. Tie lines were flown north-south approximately twelve miles apart. A total of 16,880.5 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 2925 line miles are in this quadrangle. The purpose of this study is to acquire and compile geologic and other information with which to assess the magnitude and distribution of uranium resources and to determine areas favorable for the occurrence of uranium in the United States.

Not Available

1981-04-01T23:59:59.000Z

263

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) on New Horizons. Space Sci. Rev., this volume  

E-Print Network (OSTI)

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) comprises the hardware and accompanying science investigation on the New Horizons spacecraft to measure pick-up ions from Pluto’s outgassing atmosphere. To the extent that Pluto retains its characteristics similar to those of a “heavy comet ” as detected in stellar occultations since the early 1980s, these measurements will characterize the neutral atmosphere of Pluto while providing a consistency check on the atmospheric escape rate at the encounter epoch with that deduced from the atmospheric structure at lower altitudes by the ALICE, REX, and SWAP experiments on New Horizons. In addition, PEPSSI will characterize any extended ionosphere and solar wind interaction while also characterizing the energetic particle environment of Pluto, Charon, and their associated system. First proposed for development for the Pluto Express mission in September 1993, what became the PEPSSI instrument went through a number of development stages to meet the requirements of such an instrument for a mission to Pluto while minimizing the required spacecraft resources. The PEPSSI instrument provides for measurements of ions (with compositional information) and electrons from 10s of keV to ~1 MeV in a 120 ° x 12 ° fan-shaped beam in six sectors for 1.5 kg and ~2.5

Ralph L. Mcnutt; Stefano A. Livi; Reid S. Gurnee; Matthew E. Hill; Kim A; G. Bruce Andrews; Edwin P. Keath; Stamatios M. Krimigis; Donald G; Barry Tossman; Fran Bagenal; John D. Boldt; Walter Bradley; William S; George C. Ho; Stephen E. Jaskulek; Thomas W. Lefevere; Geoffrey A. Marcus; John R. Hayes; G. Ty Moore; Bruce D. Williams; Wilson Iv; L. E. Brown; M. Kusterer

2007-01-01T23:59:59.000Z

264

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) on the New Horizons Mission  

E-Print Network (OSTI)

The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) comprises the hardware and accompanying science investigation on the New Horizons spacecraft to measure pick-up ions from Pluto's outgassing atmosphere. To the extent that Pluto retains its characteristics similar to those of a "heavy comet" as detected in stellar occultations since the early 1980s, these measurements will characterize the neutral atmosphere of Pluto while providing a consistency check on the atmospheric escape rate at the encounter epoch with that deduced from the atmospheric structure at lower altitudes by the ALICE, REX, and SWAP experiments on New Horizons. In addition, PEPSSI will characterize any extended ionosphere and solar wind interaction while also characterizing the energetic particle environment of Pluto, Charon, and their associated system. First proposed for development for the Pluto Express mission in September 1993, what became the PEPSSI instrument went through a number of development stages to meet the requirements of such an instrument for a mission to Pluto while minimizing the required spacecraft resources. The PEPSSI instrument provides for measurements of ions (with compositional information) and electrons from 10s of keV to ~1 MeV in a 120 deg x 12 deg fan-shaped beam in six sectors for 1.5 kg and ~2.5 W.

Ralph L. McNutt, Jr.; Stefano A. Livi; Reid S. Gurnee; Matthew E. Hill; Kim A. Cooper; G. Bruce Andrews; Edwin P. Keath; Stamatios M. Krimigis; Donald G. Mitchell; Barry Tossman; Fran Bagenal; John D. Boldt; Walter Bradley; William S. Devereux; George C. Ho; Stephen E. Jaskulek; Thomas W. LeFevere; Horace Malcom; Geoffrey A. Marcus; John R. Hayes; G. Ty Moore; Bruce D. Williams; Paul Wilson IV; L. E. Brown; M. Kusterer; J. Vandegriff

2007-09-27T23:59:59.000Z

265

AN ENGINE EXHAUST PARTICLE SIZERTM SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS  

DOE Green Energy (OSTI)

There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

Johnson, T; Caldow, R; Pucher, A; Mirme, A; Kittelson, D

2003-08-24T23:59:59.000Z

266

AN ENGINE EXHAUST PARTICLE SIZER{trademark} SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS  

DOE Green Energy (OSTI)

There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

Johnson, T: Caldow, R; Pucher, A Mirme, A Kittelson, D

2003-08-24T23:59:59.000Z

267

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

268

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

269

Atmospheric pressure flow reactor / aerosol mass spectrometer studies of tropospheric aerosol nucleat and growth kinetics. Final report, June, 2001  

Science Conference Proceedings (OSTI)

The objective of this program was to determine the mechanisms and rates of growth and transformation and growth processes that control secondary aerosol particles in both the clear and polluted troposphere. The experimental plan coupled an aerosol mass spectrometer (AMS) with a chemical ionization mass spectrometer to provide simultaneous measurement of condensed and particle phases. The first task investigated the kinetics of tropospheric particle growth and transformation by measuring vapor accretion to particles (uptake coefficients, including mass accommodation coefficients and heterogeneous reaction rate coefficients). Other work initiated investigation of aerosol nucleation processes by monitoring the appearance of submicron particles with the AMS as a function of precursor gas concentrations. Three projects were investigated during the program: (1) Ozonolysis of oleic acid aerosols as model of chemical reactivity of secondary organic aerosol; (2) Activation of soot particles by measurement deliquescence in the presence of sulfuric acid and water vapor; (3) Controlled nucleation and growth of sulfuric acid aerosols.

Worsnop, Douglas R.

2001-06-01T23:59:59.000Z

270

Comparison of Raindrop Size Distribution Measurements by a Joss-Waldvogel Disdrometer, a PMS 2DG Spectrometer, and a POSS Doppler Radar  

Science Conference Proceedings (OSTI)

Three techniques for the measurement of raindrop size distributions are compared using data from a Joss-Waldvogel disdrometer (JWD), a Particle Measuring Systems 2DG spectrometer (PMS), and an Atmospheric Environment Service (AES) Precipitation ...

B. E. Sheppard; P. I. Joe

1994-08-01T23:59:59.000Z

271

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility  

SciTech Connect

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution {approx} 50. It has been used at the LULI-2000 laser facility at Ecole Polytechnique (France) to measure the {Delta}n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

Reverdin, Charles; Caillaud, T.; Gilleron, F.; Pain, J. C.; Silvert, V.; Soullie, G.; Villette, B. [CEA, DAM, DIF, 91297 Arpajon (France); Thais, Frederic; Loisel, Guillaume; Blenski, T.; Poirier, M. [CEA, DSM, IRAMIS, Service Photons, Atomes et Molecules, 91191 Gif-sur-Yvette (France); Busquet, M. [ARTEP Inc, Ellicott City, Maryland 21042 (United States); Bastiani-Ceccotti, S.; Serres, F. [LULI, Ecole Polytechnique, CNRS, CEA, UPMC, route de Saclay, 91128 Palaiseau (France); Ducret, J. E. [CELIA, UMR5107, CEA, CNRS, Universite de Bordeaux, 33400 Talence (France); Foelsner, W. [Max Planck Instituet fuer Quantum Optik, 85748 Garching (Germany); Gilles, D.; Turck-Chieze, S. [CEA, DSM, IRFU, Service d'astrophysique, 91191 Gif-sur-Yvette (France)

2012-10-15T23:59:59.000Z

272

A Comparison of Total Column Ozone Values Derived from the Global Ozone Monitoring Experiment (GOME), the Tiros Operational Vertical Sounder (TOVS), and the Total Ozone Mapping Spectrometer (TOMS)  

Science Conference Proceedings (OSTI)

A comparison of total column ozone data retrieved from the Global Ozone Monitoring Experiment (GOME), the Tiros Operational Vertical Sounder (TOVS), and the Total Ozone Mapping Spectrometer (TOMS) for the years 1996, 1997, 1998, and 1999 is ...

Gary K. Corlett; Paul S. Monks

2001-05-01T23:59:59.000Z

273

Development of Soft Ionization for Particulate Organic Detection with the Aerodyne Aerosol Mass Spectrometer  

SciTech Connect

During this DOE SBIR Phase II project, we have successfully developed several soft ionization techniques, i.e., ionization schemes which involve less fragmentation of the ions, for use with the Aerodyne time-of-flight aerosol mass spectrometer (ToF-AMS). Vacuum ultraviolet single photon ionization was demonstrated in the laboratory and deployed in field campaigns. Vacuum ultraviolet single photon ionization allows better identification of organic species in aerosol particles as shown in laboratory experiments on single component particles, and in field measurements on complex multi-component particles. Dissociative electron attachment with lower energy electrons (less than 30 eV) was demonstrated in the measurement of particulate organics in chamber experiments in Switzerland, and is now a routine approach with AMS systems configured for bipolar, negative ion detection. This technique is particularly powerful for detection of acidic and other highly oxygenated secondary organic aerosol (SOA) chemical functionality. Low energy electron ionization (10 to 12 eV) is also a softer ionization approach routinely available to AMS users. Finally, Lithium ion attachment has been shown to be sensitive to more alkyl-like chemical functionality in SOA. Results from Mexico City are particularly exciting in observing changes in SOA molecular composition under different photochemical/meteorological conditions. More recent results detecting biomass burns at the Montana fire lab have demonstrated quantitative and selective detection of levoglucosan. These soft ionization techniques provide the ToF-AMS with better capability for identifying organic species in ambient atmospheric aerosol particles. This, in turn, will allow more detailed study of the sources, transformations and fate of organic-containing aerosol.

Trimborn, A; Williams, L R; Jayne, J T; Worsnop, D R

2008-06-19T23:59:59.000Z

274

Design and development of an ultrafine particle reflection-time-of-flight mass spectrometer  

E-Print Network (OSTI)

The primary motivation for the research is to study the effect of small particles on global climate. The study can also help to understand the dynamics involved with gas to particle conversion, which is being debated to be a rich source for atmospheric aerosol. However, the most important use would be to study health effects, since small particles easily diffuse into the lungs, with seemingly little physiological filtration mechanism. The research work involves the design, development and characterization of a single-ultrafine-particle mass spectrometer. The instrument aerodynamically size selects fine and ultrafine aerosol particles (size range 20 nm-1 []m), with a constant Stokes number, and focuses them into a vacuum chamber. This is achieved by changing the upstream pressure of the inlet, which changes aerodynamic drag experienced by the particle. After its entry into the chamber, the particle is ablated by a high power excimer laser, which produces ions from the original molecular constituents. Reflectron time-of-flight mass spectrometry is utilized to analyze the ions, and thus the chemical composition of the particle that was hit. The present work is aimed to overcome the shortcomings of previous instruments, while allowing for increased portability. The instrument is designed, fabricated and experimentally characterized. The first phase involves analysis of the particle beam generated by the inlet. An atomizer generates aerosols from a solution of 5% oleic acid and ethanol. The polydisperse aerosol is passed through a differential mobility analyzer to make a monodisperse mixture, which is transmitted through the inlet. The monodisperse particle beam is intercepted by glass slides, and the spot sizes are indicative of the beam shape and width at the slide positions. A theoretical analysis of the fluid flow field and particle trajectory is developed to correlate with the experimental results. The second phase involves calibration of the mass spectra, and measuring some particulate composition from the laboratory room air.

Das, Rishiraj

2002-01-01T23:59:59.000Z

275

ACTIVE REGION MOSS: DOPPLER SHIFTS FROM HINODE/EXTREME-ULTRAVIOLET IMAGING SPECTROMETER OBSERVATIONS  

Science Conference Proceedings (OSTI)

Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper, we have used an active region observation recorded by the Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode on 2007 December 12 to measure the Doppler shifts in the moss regions. We have distinguished the moss regions from the rest of the active region by defining a low-density cutoff as derived by Tripathi et al. in 2010. We have carried out a very careful analysis of the EIS wavelength calibration based on the method described by Young et al. in 2012. For spectral lines having maximum sensitivity between log T = 5.85 and log T = 6.25 K, we find that the velocity distribution peaks at around 0 km s{sup -1} with an estimated error of 4-5 km s{sup -1}. The width of the distribution decreases with temperature. The mean of the distribution shows a blueshift which increases with increasing temperature and the distribution also shows asymmetries toward blueshift. Comparing these results with observables predicted from different coronal heating models, we find that these results are consistent with both steady and impulsive heating scenarios. However, the fact that there are a significant number of pixels showing velocity amplitudes that exceed the uncertainty of 5 km s{sup -1} is suggestive of impulsive heating. Clearly, further observational constraints are needed to distinguish between these two heating scenarios.

Tripathi, Durgesh [Inter-University Centre for Astronomy and Astrophysics, Pune University Campus, Pune 411007 (India); Mason, Helen E. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Klimchuk, James A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2012-07-01T23:59:59.000Z

276

VELOCITY CHARACTERISTICS OF EVAPORATED PLASMA USING HINODE/EUV IMAGING SPECTROMETER  

Science Conference Proceedings (OSTI)

This paper presents a detailed study of chromospheric evaporation using the EUV Imaging Spectrometer (EIS) onboard Hinode in conjunction with hard X-ray (HXR) observations from Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). The advanced capabilities of EIS were used to measure Doppler shifts in 15 emission lines covering the temperature range T = 0.05-16 MK during the impulsive phase of a C-class flare on 2007 December 14. Blueshifts indicative of the evaporated material were observed in six emission lines from Fe XIV-XXIV (2-16 MK). Upflow velocity (v{sub up}) was found to scale with temperature as v{sub up} (km s{sup -1}) {approx} 8-18T(MK). Although the hottest emission lines, Fe XXIII and Fe XXIV, exhibited upflows of >200 km s{sup -1}, their line profiles were found to be dominated by a stationary component in contrast to the predictions of the standard flare model. Emission from O VI-Fe XIII lines (0.5-1.5 MK) was found to be redshifted by v{sub down} (km s{sup -1}) {approx} 60-17T (MK) and was interpreted as the downward-moving 'plug' characteristic of explosive evaporation. These downflows occur at temperatures significantly higher than previously expected. Both upflows and downflows were spatially and temporally correlated with HXR emission observed by RHESSI that provided the properties of the electron beam deemed to be the driver of the evaporation. The energy flux of the electron beam was found to be {approx}>5 x 10{sup 10} erg cm{sup -2} s{sup -1}, consistent with the value required to drive explosive chromospheric evaporation from hydrodynamic simulations.

Milligan, Ryan O.; Dennis, Brian R. [Solar Physics Laboratory (Code 671), Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2009-07-10T23:59:59.000Z

277

Fieldable Fourier Transform Spectrometer: System Construction, Background Variability Measurements, and Chemical Attack Warning Experiments  

SciTech Connect

The infrared sensors task at the Pacific Northwest National Laboratory (PNNL) is focused on the science and technology of remote and in-situ chemical sensors for detecting proliferation and countering terrorism. Missions to be addressed by remote chemical sensor development will include detecting proliferation of nuclear or chemical weapons, and providing warning of terrorist use of chemical weapons. Missions to be addressed by in-situ chemical sensor development include countering terrorism by screening luggage, personnel, and shipping containers for explosives, firearms, narcotics, chemical weapons, or chemical weapons residues, and mapping contaminated areas. The science and technology relevant to these primary missions is also likely to be useful for battlefield chemical weapons defense, air operations support, monitoring emissions from chemical weapons destruction facilities or industrial chemical plants, and law enforcement applications. PNNL will seek to serve organizations with direct interest in these missions through collaborative research and development efforts approved by NA-22. During FY02, PNNL began assembling a remote IR detection capability that would allow field experiments to be conducted. The capability consists of a commercially available FTIR (Fourier Transform Infrared) emission spectrometer and a frequency-modulation differential-absorption LIDAR (FM-DIAL) system being developed at PNNL. To provide environmental protection for these systems, a large, well insulated, temperature controlled trailer was specified and procured. While the FTIR system was field-ready, the FM-DIAL system required many modifications to prepare for field deployment. This document provides an overview of the FTIR system, summarizes the modifications made to the FM-DIAL system, and describes the salient features of the remote systems trailer.

Hatchell, Brian K.; Harper, Warren W.; Batishko, Charles R.; Johnson, Timothy J.; Sheen, David M.; Stewart, Timothy L.; Schultz, John F.

2002-10-01T23:59:59.000Z

278

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

279

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

280

HINODE/EXTREME-ULTRAVIOLET IMAGING SPECTROMETER OBSERVATIONS OF THE TEMPERATURE STRUCTURE OF THE QUIET CORONA  

Science Conference Proceedings (OSTI)

We present a differential emission measure (DEM) analysis of the quiet solar corona on disk using data obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on Hinode. We show that the expected quiet-Sun DEM distribution can be recovered from judiciously selected lines, and that their average intensities can be reproduced to within 30%. We present a subset of these selected lines spanning the temperature range log T = 5.6-6.4 K that can be used to derive the DEM distribution reliably, including a subset of iron lines that can be used to derive the DEM distribution free of the possibility of uncertainties in the elemental abundances. The subset can be used without the need for extensive measurements, and the observed intensities can be reproduced to within the estimated uncertainty in the pre-launch calibration of EIS. Furthermore, using this subset, we also demonstrate that the quiet coronal DEM distribution can be recovered on size scales down to the spatial resolution of the instrument (1'' pixels). The subset will therefore be useful for studies of small-scale spatial inhomogeneities in the coronal temperature structure, for example, in addition to studies requiring multiple DEM derivations in space or time. We apply the subset to 45 quiet-Sun data sets taken in the period 2007 January to April, and show that although the absolute magnitude of the coronal DEM may scale with the amount of released energy, the shape of the distribution is very similar up to at least log T approx 6.2 K in all cases. This result is consistent with the view that the shape of the quiet-Sun DEM is mainly a function of the radiating and conducting properties of the plasma and is fairly insensitive to the location and rate of energy deposition. This universal DEM may be sensitive to other factors such as loop geometry, flows, and the heating mechanism, but if so they cannot vary significantly from quiet-Sun region to region.

Brooks, David H.; Warren, Harry P. [Space Science Division, Code 7673, Naval Research Laboratory, Washington, DC 20375 (United States); Williams, David R. [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); Watanabe, Tetsuya, E-mail: dhbrooks@ssd5.nrl.navy.mi [National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan)

2009-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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.


281

ARM - Midlatitude Continental Convective Clouds - Ultra High Sensitivity Aerosol Spectrometer(tomlinson-uhsas)  

DOE Data Explorer (OSTI)

Ultra High Sensitivity Aerosol Spectrometer (UHSASA) A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Jason Tomlinson; Mike Jensen

282

ARM - Midlatitude Continental Convective Clouds - Ultra High Sensitivity Aerosol Spectrometer(tomlinson-uhsas)  

SciTech Connect

Ultra High Sensitivity Aerosol Spectrometer (UHSASA) A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Jason Tomlinson; Mike Jensen

2012-02-28T23:59:59.000Z

283

An electron energy loss spectrometer designed for studies of electronic energy losses and spin waves in the large momentum regime  

Science Conference Proceedings (OSTI)

Based on 143 deg. electrostatic deflectors we have realized a new spectrometer for electron energy loss spectroscopy which is particularly suitable for studies on surface spin waves and other low energy electronic energy losses. Contrary to previous designs high resolution is maintained even for diffuse inelastic scattering due to a specific management of the angular aberrations in combination with an angle aperture. The performance of the instrument is demonstrated with high resolution energy loss spectra of surface spin waves on a cobalt film deposited on the Cu(100) surface.

Ibach, H. [Peter Gruenberg Institut PGI-3, Forschungszentrum Juelich, 52425 Juelich (Germany); Juelich Aachen Research Alliance - Fundamentals of Future Information Technologies (JARA-FIT), 52425 Juelich (Germany); Rajeswari, J.; Schneider, C. M. [Peter Gruenberg Institut PGI-6, Forschungszentrum Juelich, 52425 Juelich (Germany); Juelich Aachen Research Alliance - Fundamentals of Future Information Technologies (JARA-FIT), 52425 Juelich (Germany)

2011-12-15T23:59:59.000Z

284

Conversion electrons used to monitor the energy scale of electron spectrometer near tritium endpoint - a simulation study  

E-Print Network (OSTI)

Measurements of the endpoint region of the tritium beta-decay spectrum provides good possibility to determine neutrino mass. This, however, needs a perfect monitoring of the spectrometer energy scale. A parallel measurement of electron line of known energy - in particular the 83mKr conversion K-line - may serve well to this purpose. The 83Rb decaying to 83mKr seems to be a very suitable radioactive source due to its halflife of 86.2 day. In this work, we determine the amount of 83Rb which is necessary for a successful monitoring.

M. Rysavy

2006-01-15T23:59:59.000Z

285

Development of a variable-temperature ion mobility/ time-of-flight mass spectrometer for separation of electronic isomers  

E-Print Network (OSTI)

The construction of a liquid nitrogen-cooled ion mobility spectrometer coupled with time-of-flight mass spectrometry was implemented to demonstrate the ability to discriminate between electronic isomers. Ion mobility allows for the separation of ions based on differing cross-sections-to-charge ratio. This allows for the possible discrimination of species with same mass if the ions differ by cross-section. Time-offlight mass spectrometry was added to mass identify the separated peak for proper identification. A liquid nitrogen-cooled mobility cell was employed for a two-fold purpose. First, the low temperatures increase the peak resolution to aid in resolving the separated ions. This is necessary when isomers may have similar cross-sections. Second, low temperature shortens the mean free path and decreases the neutral buffer gas speeds allowing for more interactions between the ions and the drift gas. Kr2+ study was performed to verify instrument performance. The variable-temperature ion mobility spectrometer was utilized to separate the distonic and conventional ion forms of CH3OH, CH3F, and CH3NH2 and to discriminate between the keto and enol forms of the acetone radical cation. Density functional theory and ab initio calculations were employed to aid in proper identification of separating isomers. Monte Carlo integration tools were also developed to predict ion cross-section and resolution within a buffer gas.

Verbeck, Guido Fridolin

2006-05-01T23:59:59.000Z

286

A Comprehensive Search for Gamma-Ray Lines in the First Year of Data from the INTEGRAL Spectrometer  

E-Print Network (OSTI)

We have carried out an extensive search for gamma-ray lines in the first year of public data from the Spectrometer (SPI) on the INTEGRAL mission. INTEGRAL has spent a large fraction of its observing time in the Galactic Plane with particular concentration in the Galactic Center (GC) region (~ 3 Msec in the first year). Hence the most sensitive search regions are in the Galactic Plane and Center. The phase space of the search spans the energy range 20-8000 keV and line widths from 0-1000 keV (FWHM). It includes both diffuse and point-like emission. We have searched for variable emission on time scales down to ~ 1000 sec. Diffuse emission has been searched for on a range of different spatial scales from ~ 20 deg (the approximate field-of-view of the spectrometer) up to the entire Galactic Plane. Our search procedures were verified by the recovery of the known gamma-ray lines at 511 keV and 1809 keV at the appropriate intensities and significances. We find no evidence for any previously unknown gamma-ray lines. The upper limits range from a few x 10^-5 cm^-2 s^-1 to a few x 10^-2 cm^-2 s^-1 depending on line width, energy and exposure; regions of strong instrumental background lines were excluded from the search. Comparison is made between our results and various prior predictions of astrophysical lines.

B. J. Teegarden; K. Watanabe

2006-04-12T23:59:59.000Z

287

Characterizing Exoplanets in the Visible and Infrared: A Spectrometer Concept for the EChO Space Mission  

E-Print Network (OSTI)

Transit-spectroscopy of exoplanets is one of the key observational techniques to characterize the extrasolar planet and its atmosphere. The observational challenges of these measurements require dedicated instrumentation and only the space environment allows an undisturbed access to earth-like atmospheric features such as water or carbon-dioxide. Therefore, several exoplanet-specific space missions are currently being studied. One of them is EChO, the Exoplanet Characterization Observatory, which is part of ESA's Cosmic Vision 2015-2025 program, and which is one of four candidates for the M3 launch slot in 2024. In this paper we present the results of our assessment study of the EChO spectrometer, the only science instrument onboard this spacecraft. The instrument is a multi-channel all-reflective dispersive spectrometer, covering the wavelength range from 400 nm to 16 microns simultaneously with a moderately low spectral resolution. We illustrate how the key technical challenge of the EChO mission - the high...

Glauser, A M; Krause, O; Henning, Th; Benneke, B; Bouwman, J; Cubillos, P E; Crossfield, I J M; Detre, Ö H; Ebert, M; Grözinger, U; Güdel, M; Harrington, J; Justtanont, K; Klaas, U; Lenzen, R; Madhusudhan, N; Meyer, M R; Mordasini, C; Müller, F; Ottensamer, R; Plesseria, J -Y; Quanz, S P; Reiners, A; Renotte, E; Rohloff, R -R; Scheithauer, S; Schmid, H M; Schrader, J -R; Seemann, U; Stam, D; Vandenbussche, B; Wehmeier, U

2013-01-01T23:59:59.000Z

288

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors  

Science Conference Proceedings (OSTI)

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/{Delta}m > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detection by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH{sub 3}.

Andersen, T.; Jensen, R.; Christensen, M. K.; Chorkendorff, I. [Department of Physics, Danish National Research Foundation's Center for Individual Nanoparticle Functionality (CINF), Technical University of Denmark, Building 312, DK-2800 Kgs. Lyngby (Denmark); Pedersen, T.; Hansen, O. [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark)

2012-07-15T23:59:59.000Z

289

Construction of. gamma pi. /sup 0/ spectrometer and photon tagging facility at Bates Linear Accelerator. Final report, July 31, 1979-July 31, 1980  

SciTech Connect

The funds provided under Contract No. DE-AC02-79ER10486 were totally expended for hardware and supplies required by two related devices at the Bates Linear Accelerator. These were a photon tagging facility and a ..gamma pi../sup 0/ spectrometer in Beam Line C of the new South Experimental Hall. Construction was begun in November of 1979 and both systems became fully operational in the summer of 1981. Preliminary data was taken in 1980 with a prototype ..gamma pi../sup 0/ spectrometer will be carried out in the fall of 1981 and spring of 1982. The photon tagging system has been used successfully to calibrate the ..gamma pi../sup 0/ spectrometer for the BU - MIT collaboration and to test a lead glass detector system for Brandeis University.

Booth, E.C.

1981-08-01T23:59:59.000Z

290

Differential Mobility Spectrometry/Mass Spectrometry: The Design of a New Mass Spectrometer for Real-Time Chemical Analysis in the Field  

SciTech Connect

The design of a prototype, field-portable mass spectrometer (MS) is described. The MS has been designed with an atmospheric interface in order to couple the system to a commercially available differential mobility spectrometer. The differential mobility spectrometer provides selective injection of trace-level analytes of interest into the inlet of the MS for real-time chemical detection. To accomplish this task, the MS design incorporates the use of an electrodynamic ion funnel to transport the ion beam, generated at atmospheric pressure, to the high-vacuum chamber that houses the mass analyzer. This leads to a design that utilizes two stages of differential pumping to achieve an overall pressure drop from atmosphere (760 Torr) to approximately 1 ×

,

2010-08-01T23:59:59.000Z

291

Spectroscopy of the methane {nu}{sub 3} band with an accurate midinfrared coherent dual-comb spectrometer  

SciTech Connect

We demonstrate a high-accuracy dual-comb spectrometer centered at 3.4 {mu}m. The amplitude and phase spectra of the P, Q, and partial R branches of the methane {nu}{sub 3} band are measured at 25 to 100 MHz point spacing with resolution under 10 kHz and a signal-to-noise ratio of up to 3500. A fit of the absorbance and phase spectra yields the center frequency of 132 rovibrational lines. The systematic uncertainty is estimated to be 300 kHz, which is 10{sup -3} of the Doppler width and a 10-fold improvement over Fourier transform spectroscopy. These data quantify the accuracy and resolution achievable with direct comb spectroscopy in the midinfrared.

Baumann, E.; Giorgetta, F. R.; Swann, W. C.; Zolot, A. M.; Coddington, I.; Newbury, N. R. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

2011-12-15T23:59:59.000Z

292

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

293

Operation of a Single-Photon-Counting X-Ray Charge-Coupled Device Camera Spectrometer in a Petawatt Environment  

Science Conference Proceedings (OSTI)

The use of a single-photon-counting x-ray CCD (charge-coupled device) camera as an x-ray spectrometer is a well-established technique in ultrashort-pulse laser experiments. In single-photon-counting mode, the pixel value of each readout pixel is proportional to the energy deposited from the incident x-ray photon. For photons below 100 keV, a significant fraction of the events deposits all the energy in a single pixel. A histogram of the pixel readout values gives a good approximation of the x-ray spectrum. This technique requires almost no alignment, but it is very sensitive to signal-to-background issues, especially in a high-energy petawatt environment.

Stoeckl, C.; Theobald, W.; Sangster, T.C.; Key, M.H.; Patel, P.; Zhang, B.B.; Clarke, R.; Karsch, S.; Norreys, P.

2004-10-12T23:59:59.000Z

294

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

295

Total Absorption Gamma-ray Spectrometer (TAGS) Intensity Distributions from INL's Gamma-Ray Spectrometry Center  

DOE Data Explorer (OSTI)

A 252Cf fission-product source and the INL on-line isotope separator were used to supply isotope-separated fission-product nuclides to a total absorption -ray spectrometer. This spectrometer consisted of a large (25.4-cm diameter x 30.5-cm long) NaI(Tl) detector with a 20.3-cm deep axial well in which is placed a 300-mm2 x 1.0-mm Si detector. The spectra from the NaI(Tl) detector are collected both in the singles mode and in coincidence with the B-events detected in the Si detector. Ideally, this detector would sum all the energy of the B- rays in each cascade following the population of daughter level by B- decay, so that the event could be directly associated with a particular daughter level. However, there are losses of energy from attenuation of the rays before they reach the detector, transmission of rays through the detector, escape of secondary photons from Compton scattering, escape of rays through the detector well, internal conversion, etc., and the measured spectra are thus more complicated than the ideal case and the analysis is more complex. Analysis methods have been developed to simulate all of these processes and thus provide a direct measure of the B- intensity distribution as a function of the excitation energy in the daughter nucleus. These data yield more accurate information on the B- distribution than conventional decay-scheme studies for complex decay schemes with large decay energies, because in the latter there are generally many unobserved and observed but unplaced rays. The TAGS data have been analyzed and published [R. E. Greenwood et al., Nucl Instr. and metho. A390(1997)] for 40 fission product-nuclides to determine the B- intensity distributions. [Copied from the TAGS page at http://www.inl.gov/gammaray/spectrometry/tags.shtml]. Those values are listed on this page for quick reference.

Greenwood, R.E.

296

450-Mev/c K$sup -$ AND /anti p/ BEAMS AT THE NORTHWEST TARGET AREA OF THE BEVATRON SEPARATED BY THE COAXIAL VELOCITY SPECTROMETER  

DOE Green Energy (OSTI)

Enriched beams of 450 Mev/c K/sup -/ mesons and antiprotons have been produced by separation with the coaxial static electromagnetic velocity spectrometer. Characteristics of the final separated beams as observed in the 15- inch hydrogen bubble chamber are given together with a detailed description of the beam optics and apparatas. (auth)

Horwitz, N.; Murray, J.J.; Ross, R.R.; Tripp, R.D.

1958-06-01T23:59:59.000Z

297

X-ray crystal spectrometer for opacity measurements in the 8-18 A spectral range at the LULI laser facility  

SciTech Connect

An x-ray crystal spectrometer was built in order to measure opacities in the 8-18 A spectral range with an average spectral resolution of <{lambda}/{delta}{lambda}>{approx}400. It has been successfully used at the LULI-2000 laser facility (See C. Sauteret, rapport LULI 2001, 88 (2002) at Ecole Polytechnique (France) to measure in the same experimental conditions the 2p-3d transitions of several elements with the neighboring atomic number Z: Fe, Ni, Cu, and Ge [G. Loisel et al., High Energy Density Phys. 5, 173 (2009)]. Hence, a spectrometer with a wide spectral range is needed. This spectrometer features two lines of sight. In this example, one line of sight looks through the sample and the other one is looking directly at the backlighter emission. Both are outfitted with a spherical condensing mirror. A TlAP crystal is used for spectral dispersion. Detection is made with an image plate Fuji BAS TR2025, which is sensitive to x rays. We present some experimental results showing the performances of this spectrometer.

Reverdin, C. [CEA-DAM-DIF, F-91297 Arpajon (France); Thais, F.; Loisel, G.; Bougeard, M. [CEA-DSM-IRAMIS, F-91191 Gif-sur-Yvette (France)

2010-10-15T23:59:59.000Z

298

Performance of a Focused Cavity Aerosol Spectrometer for Measurements in the Stratosphere of Particle Size in the 0.06–2.0-µm-Diameter Range  

Science Conference Proceedings (OSTI)

A focused cavity aerosol spectrometer aboard a NASA ER-2 high-altitude aircraft provided high-resolution measurements of the size of the stratospheric particles in the 0.06–2.0-µm-diameter range in flights following the eruption of Mount Pinatubo ...

H.H. Jonsson; J.C. Wilson; C.A. Brock; R.G. Knollenberg; T.R. Newton; J.E. Dye; D. Baumgardner; S. Borrmann; G.V. Ferry; R. Pueschel; Dave C. Woods; Mike C. Pitts

1995-02-01T23:59:59.000Z

299

Airborne Laser Absorption Spectrometer Measurements of Atmospheric CO2 Column Mole Fractions: Source and Sink Detection and Environmental Impacts on Retrievals  

Science Conference Proceedings (OSTI)

We report atmospheric CO2 column abundance measurement results from a summer, 2011 series of flights of a 2.05 ?m laser absorption spectrometer on the NASA DC-8 research aircraft. The Integrated Path Differential Absorption (IPDA) method is used ...

Robert T. Menzies; Gary D. Spiers; Joseph Jacob

300

A von Hamos x-ray spectrometer based on a segmented-type diffraction crystal for single-shot x-ray emission spectroscopy and time-resolved resonant inelastic x-ray scattering studies  

SciTech Connect

We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV-9600 eV. The use of a segmented crystal results in a simple and straightforward crystal preparation that allows to preserve the spectrometer resolution and spectrometer efficiency. Application of the spectrometer for time-resolved resonant inelastic x-ray scattering and single-shot x-ray emission spectroscopy is demonstrated.

Szlachetko, J. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Nachtegaal, M.; Boni, E. de; Willimann, M.; Safonova, O.; Sa, J.; Smolentsev, G.; Szlachetko, M.; Bergamaschi, A.; Schmitt, B.; David, C.; Luecke, A. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Bokhoven, J. A. van [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Institute for Chemical and Bioengineering, ETH Zurich, 8093 Zuerich (Switzerland); Dousse, J.-Cl.; Hoszowska, J.; Kayser, Y. [Department of Physics, University of Fribourg, 1700 Fribourg (Switzerland); Jagodzinski, P. [University of Technology, Kielce (Poland)

2012-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

CdTe and Cd0.9Zn0.1Te Crystal Growth and Characterization for Nuclear Spectrometers  

Science Conference Proceedings (OSTI)

Large volume single crystals of CdTe and Cd0.9Zn0.1Te (CZT) have been grown by a controlled vertical Bridgman technique using in-house zone refined precursors and characterized through structural, electrical, optical, and spectroscopic methods. The grown crystals (diameter greater than or equal to 2.5 cm and length >10 cm) have shown promising characteristics for high-resolution room temperature solid-state radiation detectors due to their high resistivity (~1010 -cm for CdTe, and >1011 -cm for CZT) and good charge transport properties [ e ~ (2-5)x10-3 cm2/V]. The fabricated detectors in planar single element and Frisch collar configurations have shown very low leakage currents and high count rates for various sources, including Am-241, and Cs-137. The grown crystals have been further characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), and transmission two-modulator generalized ellipsometry (2-MGE). Details of the CdTe and CZT characterization results, detector fabrication steps, and testing with radiation sources are presented. The CdTe and CZT crystals have shown high prospects for low power rating solid-state nuclear spectrometers and medical imaging devices.

Mandal, Krishna [EIC Laboratories, Inc.; Kang, Sung Hoon [EIC Laboratories, Inc.; Choi, Michael [EIC Laboratories, Inc.; Wright, Gomez W [ORNL; Jellison Jr, Gerald Earle [ORNL

2006-01-01T23:59:59.000Z

302

ONE-DIMENSIONAL MODELING FOR TEMPERATURE-DEPENDENT UPFLOW IN THE DIMMING REGION OBSERVED BY HINODE/EUV IMAGING SPECTROMETER  

Science Conference Proceedings (OSTI)

We previously found a temperature-dependent upflow in the dimming region following a coronal mass ejection observed by the Hinode EUV Imaging Spectrometer (EIS). In this paper, we reanalyzed the observations along with previous work on this event and provided boundary conditions for modeling. We found that the intensity in the dimming region dramatically drops within 30 minutes from the flare onset, and the dimming region reaches the equilibrium stage after {approx}1 hr. The temperature-dependent upflows were observed during the equilibrium stage by EIS. The cross-sectional area of the flux tube in the dimming region does not appear to expand significantly. From the observational constraints, we reconstructed the temperature-dependent upflow by using a new method that considers the mass and momentum conservation law and demonstrated the height variation of plasma conditions in the dimming region. We found that a super-radial expansion of the cross-sectional area is required to satisfy the mass conservation and momentum equations. There is a steep temperature and velocity gradient of around 7 Mm from the solar surface. This result may suggest that the strong heating occurred above 7 Mm from the solar surface in the dimming region. We also showed that the ionization equilibrium assumption in the dimming region is violated, especially in the higher temperature range.

Imada, S.; Shimizu, T. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara-shi, Kanagawa 252-5210 (Japan); Hara, H.; Watanabe, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka-shi, Tokyo 181-8588 (Japan); Murakami, I. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Harra, L. K. [UCL-Mullard Space Science Laboratory, Holmbury St Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Zweibel, E. G. [Department of Astronomy, University of Wisconsin-Madison, 475 N Charter Street, Madison, WI 53706 (United States)

2011-12-10T23:59:59.000Z

303

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

304

Optical Design of a Broadband Infrared Spectrometer for Bunch Length Measurement at the Linac Coherent Light Source  

SciTech Connect

The electron pulses generated by the Linac Coherent Light Source at the SLAC National Accelerator Laboratory occur on the order of tens of femtoseconds and cannot be directly measured by conventional means. The length of the pulses can instead be reconstructed by measuring the spectrum of optical transition radiation emitted by the electrons as they move toward a conducting foil. Because the emitted radiation occurs in the mid-infrared from 0.6 to 30 microns a novel optical layout is required. Using a helium-neon laser with wavelength 633 nm, a series of gold-coated off-axis parabolic mirrors were positioned to direct a beam through a zinc selenide prism and to a focus at a CCD camera for imaging. Constructing this layout revealed a number of novel techniques for reducing the aberrations introduced into the system by the off-axis parabolic mirrors. The beam had a recorded radius of less than a millimeter at its final focus on the CCD imager. This preliminary setup serves as a model for the spectrometer that will ultimately measure the LCLS electron pulse duration.

Williams, Kiel; /SLAC

2012-09-07T23:59:59.000Z

305

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

306

Method and apparatus for combinatorial logic signal processor in a digitally based high speed x-ray spectrometer  

DOE Patents (OSTI)

A high speed, digitally based, signal processing system which accepts a digitized input signal and detects the presence of step-like pulses in the this data stream, extracts filtered estimates of their amplitudes, inspects for pulse pileup, and records input pulse rates and system livetime. The system has two parallel processing channels: a slow channel, which filters the data stream with a long time constant trapezoidal filter for good energy resolution; and a fast channel which filters the data stream with a short time constant trapezoidal filter, detects pulses, inspects for pileups, and captures peak values from the slow channel for good events. The presence of a simple digital interface allows the system to be easily integrated with a digital processor to produce accurate spectra at high count rates and allow all spectrometer functions to be fully automated. Because the method is digitally based, it allows pulses to be binned based on time related values, as well as on their amplitudes, if desired.

Warburton, William K. (1300 Mills St., Menlo Park, CA 94025); Zhou, Zhiquing (Carl) (Fremont, CA)

1999-01-01T23:59:59.000Z

307

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

308

Development of a High Resolution X-Ray Imaging Crystal Spectrometer for Measurement of Ion-Temperature and Rotation-Velocity Profiles in Fusion Energy Research Plasmas  

SciTech Connect

A new imaging high resolution x-ray crystal spectrometer (XCS) has been developed to measure continuous profiles of ion temperature and rotation velocity in fusion plasmas. Following proof-of-principle tests on the Alcator C-Mod tokamak and the NSTX spherical tokamak, and successful testing of a new silicon, pixilated detector with 1MHz count rate capability per pixel, an imaging XCS is being designed to measure full profiles of Ti and v? on C-Mod. The imaging XCS design has also been adopted for ITER. Ion-temperature uncertainty and minimum measurable rotation velocity are calculated for the C-Mod spectrometer. The affects of x-ray and nuclear-radiation background on the measurement uncertainties are calculated to predict performance on ITER.

Hill, K W; Broennimann, Ch; Eikenberry, E F; Ince-Cushman, A; Lee, S G; Rice, J E; Scott, S

2008-02-27T23:59:59.000Z

309

Parabolic versus elliptic focusing - Optimization of the focusing design of a cold triple-axis neutron spectrometer by Monte-Carlo simulations  

E-Print Network (OSTI)

We present Monte-Carlo simulations for the focusing design of a novel cold-neutron triple-axis spectrometer to be installed at the end position of the cold guide NL-1 of the research reactor FRM-II in Munich, Germany. Our simulations are of general relevance for the design of triple-axis spectrometers at end positions of neutron guides. Using the McStas program code we performed ray trajectories to compare parabolic and elliptic focusing concepts. In addition the design of the monochromator was optimized concerning crystal size and mosaic spread. The parabolic focusing concept is superior to the elliptic alternative in view of the neutron intensity distribution as a function of energy and divergence. In particular, the elliptical configuration leads to an inhomogeneous divergence distribution.

Komarek, A C; Braden, M

2011-01-01T23:59:59.000Z

310

Application of PILATUS II Detector Modules for High Resolution X-Ray Imaging Crystal Spectrometers on the Alcator C-Mod Tokamak  

Science Conference Proceedings (OSTI)

A new type of X-ray imaging crystal spectrometer for Doppler measurements of the radial profiles of the ion temperature and plasma rotation velocity in tokamak plasmas is presently being developed in a collaboration between various laboratories. The spectrometer will consist of a spherically bent crystal and a two-dimensional position sensitive detector; and it will record temporally and spatially resolved X-ray line spectra from highly-charged ions. The detector must satisfy challenging requirements with respect to count rate and spatial resolution. The paper presents the results from a recent test of a PILATUS II detector module on Alcator C-Mod, which demonstrate that the PILATUS II detector modules will satisfy these requirements.

M.L. Bitter, Ch. Borennimann, E.F. Eikenberry, K.W. Hill, A. Ince-Chushman, S.G. Lee, J.E. Rice, and S. Scott.

2007-07-23T23:59:59.000Z

311

A Novel 9.4 Tesla FT-ICR Mass Spectrometer with Improved Sensitivity, Mass Resolution, and Mass Range, for Petroleum Heavy Crude Oil Analysis  

E-Print Network (OSTI)

A Novel 9.4 Tesla FT-ICR Mass Spectrometer with Improved Sensitivity, Mass Resolution, and Mass advances in instrument speed and sensitivity. We have redesigned our custom built 9 4 tesla FT ICR New 9 = 800 000 [C32H55S1+H]+ [C35H51+H]+ We have redesigned our custom-built 9.4 tesla FT-ICR mass

Weston, Ken

312

Nanograting-based compact VUV spectrometer and beam profiler for in-situ characterization of high-order harmonic generation light sources  

SciTech Connect

A compact, versatile device for VUV beam characterization is presented. It combines the functionalities of a VUV spectrometer and a VUV beam profiler in one unit and is entirely supported by a standard DN200 CF flange. The spectrometer employs a silicon nitride transmission nanograting in combination with a micro-channel plate based imaging detector. This enables the simultaneous recording of wavelengths ranging from 10 nm to 80 nm with a resolution of 0.25 nm to 0.13 nm. Spatial beam profiles with diameters up to 10 mm are imaged with 0.1 mm resolution. The setup is equipped with an in-vacuum translation stage that allows for in situ switching between the spectrometer and beam profiler modes and for moving the setup out of the beam. The simple, robust design of the device is well suited for non-intrusive routine characterization of emerging laboratory- and accelerator-based VUV light sources. Operation of the device is demonstrated by characterizing the output of a femtosecond high-order harmonic generation light source.

Kornilov, Oleg; Wilcox, Russell; Gessner, Oliver

2010-07-09T23:59:59.000Z

313

Apr il 11, 1 988 Feasibility Study into the Use of Mechanical Choppers  

E-Print Network (OSTI)

·· Plenum Press (1980). 2. D. Moncton, in "New Rings Ivorkshop," SSRL Report 83-02 (1983). 3. G. K. Shenoy;REFERENCE 1. Go1ovchenko, J. A., in SSRL Report 83/102, ed. K. Cantwell and C. Mitchell, (1983), p. 147. 30

Kemner, Ken

314

Facilities: NHMFL 14.5 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Citation: A Pseudoatomic Model of the COPII Cage Obtained from Cryo-Electron Microscopy and Mass Spectrometry,  

E-Print Network (OSTI)

Facilities: NHMFL 14.5 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Citation ultrahigh-resolution 14.5 tesla Fourier transform ion cyclotron resonance mass spectrometry. The Mag

Weston, Ken

315

Simulation, Modeling, and Crystal Growth of Cd0.9Zn0.1Te for Nuclear Spectrometers  

Science Conference Proceedings (OSTI)

High-quality, large (10 cm long and 2.5 cm diameter), nuclear spectrometer grade Cd{sub 0.9}Zn{sub 0.1}Te (CZT) single crystals have been grown by a controlled vertical Bridgman technique using in-house zone refined precursor materials (Cd, Zn, and Te). A state-of-the-art computer model, multizone adaptive scheme for transport and phase-change processes (MASTRAP), is used to model heat and mass transfer in the Bridgman growth system and to predict the stress distribution in the as-grown CZT crystal and optimize the thermal profile. The model accounts for heat transfer in the multiphase system, convection in the melt, and interface dynamics. The grown semi-insulating (SI) CZT crystals have demonstrated promising results for high-resolution room-temperature radiation detectors due to their high dark resistivity ({rho} {approx} 2.8 x 10{sup 11} {Theta} cm), good charge-transport properties, electron and hole mobility-life-time product, {mu}{tau}{sub e} {approx} (2-5) x 10{sup -3} and {mu}{tau}{sub h} {approx} (3-5) x 10{sup -5} respectively, and low cost of production. Spectroscopic ellipsometry and optical transmission measurements were carried out on the grown CZT crystals using two-modulator generalized ellipsometry (2-MGE). The refractive index n and extinction coefficient k were determined by mathematically eliminating the {approx}3-nm surface roughness layer. Nuclear detection measurements on the single-element CZT detectors with {sup 241}Am and {sup 137}Cs clearly detected 59.6 and 662 keV energies with energy resolution (FWHM) of 2.4 keV (4.0%) and 9.2 keV (1.4%), respectively.

Mandal, Krishna [EIC Laboratories, Inc.; Kang, Sung Hoon [EIC Laboratories, Inc.; Choi, Michael [EIC Laboratories, Inc.; Bello, Job [EIC Laboratories, Inc.; Zheng, Lili [State University of New York, Stony Brook; Zhang, Hui [State University of New York, Stony Brook; Groza, Michael [Fisk University, Nashville, TN; Roy, Utpal N. [Fisk University, Nashville, TN; Burger, Arnold [Fisk University, Nashville, TN; Jellison Jr, Gerald Earle [ORNL; Holcomb, David Eugene [ORNL; Wright, Gomez W [ORNL; Williams, Joseph A [ORNL

2006-01-01T23:59:59.000Z

316

Comparison of improved Aura Tropospheric Emission Spectrometer (TES) CO{sub 2} with HIPPO and SGP aircraft profile measurements  

SciTech Connect

Comparisons are made between mid-tropospheric Tropospheric Emission Spectrometer (TES) carbon dioxide (CO{sub 2}) satellite measurements and ocean profiles from three Hiaper Pole-to-Pole Observations (HIPPO) campaigns and land aircraft profiles from the United States Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site over a 4-yr period. These comparisons are used to characterize the bias in the TES CO{sub 2} estimates and to assess whether calculated and actual uncertainties and sensitivities are consistent. The HIPPO dataset is one of the few datasets spanning the altitude range where TES CO{sub 2} estimates are sensitive, which is especially important for characterization of biases. We find that TES CO{sub 2} estimates capture the seasonal and latitudinal gradients observed by HIPPO CO{sub 2} measurements; actual errors range from 0.8–1.2 ppm, depending on the campaign, and are approximately 1.4 times larger than the predicted errors. The bias of TES versus HIPPO is within 0.85 ppm for each of the 3 campaigns; however several of the sub-tropical TES CO{sub 2} estimates are lower than expected based on the calculated errors. Comparisons of aircraft flask profiles, which are measured from the surface to 5 km, to TES CO{sub 2} at the SGP ARM site show good agreement with an overall bias of 0.1 ppm and rms of 1.0 ppm. We also find that the predicted sensitivity of the TES CO{sub 2} estimates is too high, which results from using a multi-step retrieval for CO{sub 2} and temperature. We find that the averaging kernel in the TES product corrected by a pressure-dependent factor accurately reflects the sensitivity of the TES CO{sub 2} product.

Kulawik, S. S.; Worden, J. R.; Wofsy, S. C.; Biraud, S. C.; Nassar, R.; Jones, D. B.A.; Olsen, E. T.; Osterman, G. B.

2012-02-01T23:59:59.000Z

317

Electrical Mobility Spectrometer Using a Diethylene Glycol Condensation Particle Counter for Measurement of Aerosol Size Distributions Down to 1 nm  

Science Conference Proceedings (OSTI)

We report a new scanning mobility particle spectrometer (SMPS) for measuring number size distributions of particles down to {approx}1 nm mobility diameter. This SMPS includes an aerosol charger, a TSI 3085 nano differential mobility analyzer (nanoDMA), an ultrafine condensation particle counter (UCPC) using diethylene glycol (DEG) as the working fluid, and a conventional butanol CPC (the 'booster') to detect the small droplets leaving the DEG UCPC. The response of the DEG UCPC to negatively charged sodium chloride particles with mobility diameters ranging from 1-6 nm was measured. The sensitivity of the DEG UCPC to particle composition was also studied by comparing its response to positively charged 1.47 and 1.70 nm tetra-alkyl ammonium ions, sodium chloride, and silver particles. A high resolution differential mobility analyzer was used to generate the test particles. These results show that the response of this UCPC to sub-2 nm particles is sensitive to particle composition. The applicability of the new SMPS for atmospheric measurement was demonstrated during the Nucleation and Cloud Condensation Nuclei (NCCN) field campaign (Atlanta, Georgia, summer 2009). We operated the instrument at saturator and condenser temperatures that allowed the efficient detection of sodium chloride particles but not of air ions having the same mobility. We found that particles as small as 1 nm were detected during nucleation events but not at other times. Factors affecting size distribution measurements, including aerosol charging in the 1-10 nm size range, are discussed. For the charger used in this study, bipolar charging was found to be more effective for sub-2 nm particles than unipolar charging. No ion induced nucleation inside the charger was observed during the NCCN campaign.

Jiang, J.; Kuang, C.; Chen, M.; Attoui, M.; McMurry, P. H.

2011-02-01T23:59:59.000Z

318

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

319

A portable optical emission spectroscopy-cavity ringdown spectroscopy dual-mode plasma spectrometer for measurements of environmentally important trace heavy metals: Initial test with elemental Hg  

SciTech Connect

A portable optical emission spectroscopy-cavity ringdown spectroscopy (OES-CRDS) dual-mode plasma spectrometer is described. A compact, low-power, atmospheric argon microwave plasma torch (MPT) is utilized as the emission source when the spectrometer is operating in the OES mode. The same MPT serves as the atomization source for ringdown measurements in the CRDS mode. Initial demonstration of the instrument is carried out by observing OES of multiple elements including mercury (Hg) in the OES mode and by measuring absolute concentrations of Hg in the metastable state 6s6p {sup 3}P{sub 0} in the CRDS mode, in which a palm-size diode laser operating at a single wavelength 405 nm is incorporated in the spectrometer as the light source. In the OES mode, the detection limit for Hg is determined to be 44 parts per 10{sup 9} (ppb). A strong radiation trapping effect on emission measurements of Hg at 254 nm is observed when the Hg solution concentration is higher than 50 parts per 10{sup 6} (ppm). The radiation trapping effect suggests that two different transition lines of Hg at 253.65 nm and 365.01 nm be selected for emission measurements in lower (<50 ppm) and higher concentration ranges (>50 ppm), respectively. In the CRDS mode, the detection limit of Hg in the metastable state 6s6p {sup 3}P{sub 0} is achieved to be 2.24 parts per 10{sup 12} (ppt) when the plasma is operating at 150 W with sample gas flow rate of 480 mL min{sup -1}; the detection limit corresponds to 50 ppm in Hg sample solution. Advantage of this novel spectrometer has two-fold, it has a large measurement dynamic range, from a few ppt to hundreds ppm and the CRDS mode can serve as calibration for the OES mode as well as high sensitivity measurements. Measurements of seven other elements, As, Cd, Mn, Ni, P, Pb, and Sr, using the OES mode are also carried out with detection limits of 1100, 33, 30, 144, 576, 94, and 2 ppb, respectively. Matrix effect in the presence of other elements on Hg measurements has been found to increase the detection limit to 131 ppb. These elements in lower concentrations can also be measured in the CRDS mode when a compact laser source is available to be integrated into the spectrometer in the future. This exploratory study demonstrates a new instrument platform using an OES-CRDS dual-mode technique for potential field applications.

Sahay, Peeyush; Scherrer, Susan T.; Wang Chuji [Department of Physics and Astronomy, Mississippi State University, Starkville, Mississippi 39759 (United States)

2012-09-15T23:59:59.000Z

320

ablation laser spectrometer  

E-Print Network (OSTI)

Hydrogen from Biomass Catalytic Reforming of Pyrolysis Vapors R. Evans, L. Boyd, C. Elam, S-23, 2003 #12;Project Goals Demonstrate the production of hydrogen from biomass by pyrolysis ­steam catalysts and reactor configuration for fluid bed reforming of biomass pyrolysis liquid at pilot scale (500

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321

Choosing the Right Spectrometer  

Science Conference Proceedings (OSTI)

... 1200 Intensity Focusing Analyzer ... 1. What energy resolution (?h?) is required? ... 1. What are the energies (h?), ie time scales (?t ~1/?), of interest? ...

2013-06-18T23:59:59.000Z

322

Backscattering Spectrometer hazards Analysis  

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

software that may be required to extract the information of interest from the simulated data. 1.3 Workshop Plan The workshop was held August 26-28 at the Villa Mondragone...

323

Optical-Fiber-Based, Time-Resolved Photoluminescence Spectrometer for Thin-Film Absorber Characterization and Analysis of TRPL Data for CdS/CdTe Interface: Preprint  

DOE Green Energy (OSTI)

We describe the design of a time resolved photoluminescence (TRPL) spectrometer for rapid semiconductor absorber characterization. Simplicity and flexibility is achieved by using single optical fiber to deliver laser pulses and to collect photoluminescence. We apply TRPL for characterization of CdS/CdTe absorbers after deposition, CdCl2 treatment, Cu doping, and back contact formation. Data suggest this method could be applied in various stages of PV device processing. Finally, we show how to analyze TRPL data for CdS/CdTe absorbers by considering laser light absorption depth and intermixing at CdS/CdTe interface.

Kuciauskas, D.; Duenow, J. N.; Kanevce, A.; Li, J. V.; Young, M. R.; Dippo, P.; Levi, D. H.

2012-06-01T23:59:59.000Z

324

Development of A Cryogenic Drift Cell Spectrometer and Methods for Improving the Analytical Figures of Merit for Ion Mobility-Mass Spectrometry Analysis  

E-Print Network (OSTI)

A cryogenic (325-80 K) ion mobility-mass spectrometer was designed and constructed in order to improve the analytical figures-of-merit for the chemical analysis of small mass analytes using ion mobility-mass spectrometry. The instrument incorporates an electron ionization source, a quadrupole mass spectrometer, a uniform field drift cell spectrometer encased in a cryogenic envelope, and an orthogonal geometry time-of-flight mass spectrometer. The analytical benefits of low temperature ion mobility are discussed in terms of enhanced separation ability, ion selectivity and sensitivity. The distinction between resolving power and resolution for ion mobility is also discussed. Detailed experimental designs and rationales are provided for each instrument component. Tuning and calibration data and methods are also provided for the technique. Proof-of-concept experiments for an array of analytes including rare gases (argon, krypton, xenon), hydrocarbons (acetone, ethylene glycol, methanol), and halides (carbon tetrachloride) are provided in order to demonstrate the advantages and limitations of the instrument for obtaining analytically useful information. Trendline partitioning of small analyte ions based on chemical composition is demonstrated as a novel chemical analysis method. The utility of mobility-mass analysis for mass selected ions is also demonstrated, particularly for probing the ion chemistry which occurs in the drift tube for small mass ions. As a final demonstration of the separation abilities of the instrument, the electronic states of chromium and titanium (ground and excited) are separated with low temperature. The transition metal electronic state separations demonstrated here are at the highest resolution ever obtained for ion mobility methods. The electronic conformational mass isomers of methanol (conventional and distonic) are also partially separated at low temperature. Various drift gases (helium, neon, and argon) are explored for the methanol system in order to probe stronger ion-neutral interaction potentials and effectuate higher resolution separations of the two isomeric ions. Finally, two versatile ion source designs and a method for axially focusing ions at low pressure (1-10 torr) using electrostatic fields is presented along with some preliminary work on the ion sources.

May, Jody C.

2009-08-01T23:59:59.000Z

325

Design of a Real-Time Scanning Electrical Mobility Spectrometer and its Application in Study of Nanoparticle Aerosol Generation  

E-Print Network (OSTI)

A real-time, mobile Scanning Electrical Mobility Spectrometer (SEMS) was designed using a Condensation Particle Counter (CPC) and Differential Mobility Analyzer (DMA) to measure the size distribution of nanoparticles. The SEMS was calibrated using monodisperse Polystyrene Latex (PSL) particles, and was then applied to study the size distribution of TiO2 nanoparticle aerosols generated by spray drying water suspensions of the nanoparticles. The nanoparticle aerosol size distribution, the effect of surfactant, and the effect of residual solvent droplets were determined. The SEMS system was designed by integrating the Electrical System, the Fluid Flow System, and the SEMS Software. It was calibrated using aerosolized Polystyrene Latex (PSL) spheres with nominal diameters of 99 nm and 204 nm. TiO2 nanoparticle aerosols were generated by atomizing water suspensions of TiO2 nanoparticles using a Collison nebulizer. Size distribution of the TiO2 aerosol was measured by the SEMS, as well as by TEM. Furthermore, the effect of surfactant, Tween 20 at four different concentrations between 0.01mM and 0.80mM, and stability of aerosol concentration with time were studied. It was hypothesized that residual particles in DI water observed during the calibration process were a mixture of impurities in water and unevaporated droplets. Solid impurities were captured on TEM grids using a point-to-plane Electrostatic Precipitator (ESP) and analyzed by Energy Dispersive Spectroscopy (EDS) while the contribution of unevaporated liquid droplets to residual particles was confirmed by size distribution measurements of aerosolized DI water in different humidity conditions. The calibration indicated that the mode diameter was found to be at 92.5nm by TEM and 95.8nm by the SEMS for 99nm nominal diameter particles, a difference of 3.6%. Similarly, the mode diameter for 204nm nominal diameter particles was found to be 194.9nm by TEM and 191nm by SEMS, a difference of 2.0%. Measurements by SEMS for TiO2 aerosol generated by Collison nebulizer indicated the mode diameters of 3mM, 6mM, and 9mM concentrations of TiO2 suspension to be 197.5nm, 200.0nm and 195.2nm respectively. On the other hand, the mode diameter was found to be approximately 95nm from TEM analysis of TiO2 powder. Additionally, concentration of particles generated decreased with time. Dynamic Light Scattering (DLS) measurements indicated agglomeration of particles in the suspension. Furthermore, the emulation of single particle distribution was not possible even after using Tween 20 in concentrations between 0.01mM and 0.80mM. From the study of residual particles in DI water, it was found that residual particles observed during the aerosolization of suspensions of DI water were composed of impurities present in DI water and unevaporated droplets of DI water. Although it was possible to observe solid residual particles on the TEM grid, EDS was not able to determine the chemical composition of these particles.

Singh, Gagan

2010-05-01T23:59:59.000Z

326

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions  

Science Conference Proceedings (OSTI)

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

Gulyuz, Kerim; Stedwell, Corey N.; Wang Da; Polfer, Nick C. [Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611 (United States)

2011-05-15T23:59:59.000Z

327

Self-calibrating mass spectrometer. Project accomplishment summary for DOE Technology Transfer Initiative project 92-Y12P-055-B1  

DOE Green Energy (OSTI)

A mass spectrometer gas analyzer analyzes gas mixtures to determine the type and relative amounts of gases that compose the mixture. Cost of the instrument is usually determined by how sensitive the device is; the more sensitive the measurements, the higher the price. Critical to getting good results from a mass spectrometer gas analyzer is having the instrument calibrated. An uncalibrated instrument will do qualitative analysis, but not quantitative analysis. The purpose of this Cooperative Research and Development Agreement (CRADA) was to develop a way to calibrate a gas analyzer with minimal effort by the operator. Using technology originally developed for nuclear weapons applications, researchers from the Oak Ridge Y-12 Plant and from Vacuum Technology, Inc. (VTI), developed a calibration method that uses metal hydride (hydrogen that is in solid form). The entire sequence is controlled by computer software developed as part of the CRADA research. After calibration, unknown gas samples are introduced, and the resulting mass spectra are compared to reference spectra appropriately adjusted by the instrument response to the calibrating hydrogen pulse. Because the shifts of the mass spectra of a number of common gases can be predicted by the shifts in the hydrogen peak, hydrogen can be used to calibrate the instrument for a variety of gases. Through the pattern recognition ability of the computer software, the analyzer works not only for hydrogen, but for other gases as well.

NONE

1996-04-18T23:59:59.000Z

328

Improvements in apparatus and procedures for using an organic liquid scintillator as a fast-neutron spectrometer for radiation protection applications  

SciTech Connect

For use in radiation protection measurements, a neutron spectrometer must have a wide energy range, good sensitivity, medium resolution, and ease of taking and reducing data. No single spectrometer meets all of these requirements. Several experiments aimed at improving and characterizing the detector response to gamma rays and neutrons were conducted. A light pipe (25 mm) was needed between the scintillator cell and the photomultiplier tube to achieve the best resolution. The light output of the scintillator as a function of gamma-ray energy was measured. Three experiments were conducted to determine the light output as a function of neutron energy. Monte Carlo calculations were made to evaluate the effects of multiple neutron scattering and edge effects in the detector. The electronic systems associated with the detector were improved with a transistorized circuit providing the bias voltage for the photomultiplier tube dynodes. This circuit was needed to obtain pulse-height linearity over the wide range of signal sizes. A special live-time clock was built to compensate for the large amount of dead time generated by the pulse-shape discrimination circuit we chose to use. 64 refs., 58 figs., 9 tabs.

Thorngate, J.H.

1987-05-15T23:59:59.000Z

329

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

330

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.

331

THE TEMPERATURE AND DENSITY STRUCTURE OF THE SOLAR CORONA. I. OBSERVATIONS OF THE QUIET SUN WITH THE EUV IMAGING SPECTROMETER ON HINODE  

Science Conference Proceedings (OSTI)

Measurements of the temperature and density structure of the solar corona provide critical constraints on theories of coronal heating. Unfortunately, the complexity of the solar atmosphere, observational uncertainties, and the limitations of current atomic calculations, particularly those for Fe, all conspire to make this task very difficult. A critical assessment of plasma diagnostics in the corona is essential to making progress on the coronal heating problem. In this paper, we present an analysis of temperature and density measurements above the limb in the quiet corona using new observations from the EUV Imaging Spectrometer (EIS) on Hinode. By comparing the Si and Fe emission observed with EIS we are able to identify emission lines that yield consistent emission measure distributions. With these data we find that the distribution of temperatures in the quiet corona above the limb is strongly peaked near 1 MK, consistent with previous studies. We also find, however, that there is a tail in the emission measure distribution that extends to higher temperatures. EIS density measurements from several density sensitive line ratios are found to be generally consistent with each other and with previous measurements in the quiet corona. Our analysis, however, also indicates that a significant fraction of the weaker emission lines observed in the EIS wavelength ranges cannot be understood with current atomic data.

Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Brooks, David H. [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

2009-07-20T23:59:59.000Z

332

The Dark Energy Spectrometer (DESpec): A Multi-Fiber Spectroscopic Upgrade of the Dark Energy Camera and Survey for the Blanco Telescope  

E-Print Network (OSTI)

We describe an initiative to build and use the Dark Energy Spectrometer (DESpec), a wide-field spectroscopic survey instrument for the Blanco 4 meter telescope at Cerro Tololo InterAmerican Observatory (CTIO) in Chile. A new system with about 4000 robotically positioned optical fibers will be interchangeable with the CCD imager of the existing Dark Energy Camera (DECam), accessing a field of view of 3.8 square degrees in a single exposure. The proposed instrument will be operated by CTIO and available for use by the astronomy community. Our collaboration proposes to use DESpec to conduct a wide, deep spectroscopic survey to study Dark Energy. In a survey of about 350 nights, the DESpec collaboration proposes to obtain spectroscopic redshifts for about 8 million galaxies over 5000 square degrees selected from the Dark Energy Survey (DES). This Dark Energy Spectroscopic Survey will advance our knowledge of cosmic expansion and structure growth significantly beyond that obtainable with imaging-only surveys. Sinc...

Abdalla, F; Bacon, D; Bridle, S; Castander, F; Colless, M; DePoy, D; Diehl, H T; Eriksen, M; Flaugher, B; Frieman, J; Gaztanaga, E; Hogan, C; Jouvel, S; Kent, S; Kirk, D; Kron, R; Kuhlmann, S; Lahav, O; Lawrence, J; Lin, H; Marriner, J; Marshall, J; Mohr, J; Nichol, R C; Sako, M; Saunders, W; Soares-Santos, M; Thomas, D; Wechsler, R; West, A; Wu, H

2012-01-01T23:59:59.000Z

333

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

334

Initial Assessment of the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR)-Based Aerosol Retrieval: Sensitivity Study  

SciTech Connect

The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) being developed for airborne measurements will offer retrievals of aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. In this study, we assess the expected accuracy of the 4STAR-based aerosol retrieval and its sensitivity to major sources of anticipated perturbations in the 4STAR measurements by adapting a theoretical approach previously developed for the AERONET measurements. The major anticipated perturbations are (1) an apparent enhancement of sky radiance at small scattering angles associated with the necessarily compact design of the 4STAR and (2) and an offset (i.e. uncertainty) of sky radiance calibration independent of scattering angle. The assessment is performed through application of the operational AERONET aerosol retrieval and constructed synthetic 4STAR-like data. Particular attention is given to the impact of these perturbations on the upwelling and downwelling broadband fluxes and the direct aerosol radiative forcing at the bottom and top of the atmosphere. The results from this study suggest that limitations in the accuracy of 4STAR-retrieved particle size distributions and scattering phase functions have diminished impact on the accuracy of retrieved bulk microphysical parameters, permitting quite accurate retrievals of properties including the effective radius (up to 10%, or 0.03), and the radiatively important optical properties, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 6%, or ±0.04). Also, the obtained results indicate that the uncertainties in the retrieved aerosol optical properties are quite small in the context of the calculated fluxes and direct aerosol radiative forcing (up to 15%, or 3 Wm-2).

Kassianov, Evgueni I.; Flynn, Connor J.; Redemann, Jens; Schmid, Beat; Russell, P. B.; Sinyuk, Alexander

2012-10-24T23:59:59.000Z

335

For more information, contact  

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

Feng Ye, yef1@ornl.gov, 865.576.0931 Feng Ye, yef1@ornl.gov, 865.576.0931 09-G00161B/gim CORELLI is a statistical chopper spectrometer with energy discrimination. CORELLI is 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

336

High flux backscattering spectrometer (HFBS)  

Science Conference Proceedings (OSTI)

... [2] University of Utah. [3] ORNL. TLCCR - HFBS specific - TLCCR-HFBS. Terrence Udovic. Wed 06/26/2013 10:00, 1, Instrument Calibration, ...

337

High flux backscattering spectrometer (HFBS)  

Science Conference Proceedings (OSTI)

... note that a larger dynamic range will result in a proportionately longer measuring time (to achieve the same counting statistics, same energy bin size ...

338

Instruments | Neutron Science | ORNL  

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

NScD Careers NScD Careers Supporting Organizations Neutron Science Home | Science & Discovery | Neutron Science | Instruments SHARE Instruments at SNS and HFIR SNS Instrument Name HFIR Instrument Name 1B NOMAD - Nanoscale-Ordered Materials Diffractometer CG-1 Development Beam Line 2 BASIS - Backscattering Spectrometer CG-1D IMAGING - Neutron Imaging Prototype Facility 3 SNAP - Spallation Neutrons and Pressure Diffractometer CG-2 GP-SANS - General-Purpose Small-Angle Neutron Scattering Diffractometer 4A MR - Magnetism Reflectometer CG-3 Bio-SANS - Biological Small-Angle Neutron Scattering Instrument 4B LR - Liquids Reflectometer CG-4C CTAX - Cold Neutron Triple-Axis Spectrometer 5 CNCS - Cold Neutron Chopper Spectrometer HB-1 PTAX - Polarized Triple-Axis Spectrometer

339

Catalytic Steam Reforming of Gasifier Tars: On-Line Monitoring of Tars with a Transportable Molecular-Beam Mass Spectrometer; Milestone Completion Report  

DOE Green Energy (OSTI)

A method for evaluating catalytic tar decomposition in real time is presented. The effectiveness of two catalysts are compared. A key technical and economic barrier to commercialization of biomass gasification technologies is the removal of tars that are unavoidably formed in this thermochemical process. Tars contain fuel value; however, they are problematic in gas engines (both reciprocating and turbine) because they condense in the fuel delivery system, forming deposits that negatively affect operation and efficiency. These tars also combust with high luminosity, potentially forming soot particles. The conventional technology for tar removal is wet scrubbing. Although this approach has shown some success, there are significant equipment and operating costs associated with it. In order to prevent the generation of toxic wastewater, the tars must be separated and either disposed as hazardous waste or, preferably, combusted in the gasification plant. A conceptually better approach is catalytic steam reforming of the tars to hydrogen and carbon monoxide (CO), effectively increasing the gasification efficiency and eliminating the problems mentioned above. In FY2000, Battelle Columbus Laboratories attempted to demonstrate integrated gasification-gas turbine operation using catalytic steam reforming of tars. NREL participated in those tests using the transportable molecular-beam mass spectrometer (TMBMS) to monitor the catalytic reactor's performance on-line [10]. Unfortunately, the pilot plant tests encountered operational problems that prevented conclusive determination of the efficacy of the selected catalyst (Battelle's DN34). In FY2001, NREL performed on-site tar steam reforming tests using a slip-stream of hot pyrolysis gas from the Thermochemical Process Development Unit (TCPDU), which was directed to a bench-scale fluidized bed reactor system designed expressly for this purpose. Supporting this effort, the TMBMS was employed to provide on-line analysis of the tar conversion. The gas composition changes were monitored by two identical gas chromatographs (GCs), and modified method 5 sampling was performed to obtain gravimetric conversion data. The combination of these analytical techniques provided definitive catalyst performance data, as well as linkage to previous and on-going work elsewhere. Two catalysts were tested: nickel (Ni) on potassium promoted alumina (Sued-Chemie C11-NK), used commercially for naphtha steam reforming, and alumina (Battelle's DN34) claimed to be effective for gasifier tar decomposition. In addition, sand was tested as an inert reference material.

Carpenter, D.; Ratcliff, M.; Dayton, D.

2002-05-01T23:59:59.000Z

340

Complete measurement of three-body photodisintegration of 3He for photon energies between 0.35 and 1.55 GeV  

E-Print Network (OSTI)

The three-body photodisintegration of 3He has been measured with the CLAS detector at Jefferson Lab, using tagged photons of energies between 0.35 GeV and 1.55 GeV. The large acceptance of the spectrometer allowed us for the first time to cover a wide momentum and angular range for the two outgoing protons. Three kinematic regions dominated by either two- or three-body contributions have been distinguished and analyzed. The measured cross sections have been compared with results of a theoretical model, which, in certain kinematic ranges, have been found to be in reasonable agreement with the data.

CLAS Collaboration; S. Niccolai; G. Audit; B. L. Berman; J. M. Laget; S. Strauch

2004-09-16T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

Design Considerations for an MEBT Chopper Absorber of 2.1 MeV H- at the Project X Injector Experiment at Fermilab  

SciTech Connect

The Project X Injector Experiment (PIXIE) will be a prototype of the Project X front end that will be used to validate the design concept and decrease technical risks. One of the most challenging components of PIXIE is the wide-band chopping system of the Medium Energy Beam Transport (MEBT) section, which will form an arbitrary bunch pattern from the initially CW 162.5 MHz 5mA beam. The present scenario assumes diverting 80% of the beam to an absorber to provide a beam with the average current of 1mA to SRF linac. This absorber must withstand a high level of energy deposition and high ion fluence, while being positioned in proximity of the superconductive cavities. This paper discusses design considerations for the absorber. Thermal and mechanical analyses of a conceptual design are presented, and future plans for the fabrication and testing of a prototype are described.

Baffes, C.; Awida, M.; Chen, A.; Eidelman, Y.; Lebedev, V.; Prost, L.; Shemyakin, A.; Solyak, N.; Yakovlev, V.; /Fermilab

2012-05-14T23:59:59.000Z

342

Absolute intensity calibration of flat-field space-resolved extreme ultraviolet spectrometer using radial profiles of visible and extreme ultraviolet bremsstrahlung continuum emitted from high-density plasmas in Large Helical Device  

Science Conference Proceedings (OSTI)

A precise absolute intensity calibration of a flat-field space-resolved extreme ultraviolet (EUV) spectrometer working in wavelength range of 60-400 A is carried out using a new calibration technique based on radial profile measurement of the bremsstrahlung continuum in Large Helical Device. A peaked vertical profile of the EUV bremsstrahlung continuum has been successfully observed in high-density plasmas (n{sub e}{>=} 10{sup 14} cm{sup -3}) with hydrogen ice pellet injection. The absolute calibration can be done by comparing the EUV bremsstrahlung profile with the visible bremsstrahlung profile of which the absolute value has been already calibrated using a standard lamp. The line-integrated profile of measured visible bremsstrahlung continuum is firstly converted into the local emissivity profile by considering a magnetic surface distortion due to the plasma pressure, and the local emissivity profile of EUV bremsstrahlung is secondly calculated by taking into account the electron temperature profile and free-free gaunt factor. The line-integrated profile of the EUV bremsstrahlung continuum is finally calculated from the local emissivity profile in order to compare with measured EUV bremsstrahlung profile. The absolute intensity calibration can be done by comparing measured and calculated EUV bremsstrahlung profiles. The calibration factor is thus obtained as a function of wavelength with excellent accuracy. It is also found in the profile analysis that the grating reflectivity of EUV emissions is constant along the direction perpendicular to the wavelength dispersion. Uncertainties on the calibration factor determined with the present method are discussed including charge-coupled device operation modes.

Dong Chunfeng; Wang Erhui [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Morita, Shigeru; Goto, Motoshi [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); National Institute for Fusion Science, Toki 509-5292, Gifu (Japan)

2011-11-15T23:59:59.000Z

343

Investigating the role of hydrogen in silicon deposition using an energy-resolved mass spectrometer and a Langmuir probe in an Ar/H{sub 2} radio frequency magnetron discharge  

SciTech Connect

The plasma parameters and ion energy distributions (IED) of the dominant species in an Ar-H{sub 2} discharge are investigated with an energy resolved mass spectrometer and a Langmuir probe. The plasmas are generated in a conventional magnetron chamber powered at 150 W, 13.56 MHz at hydrogen flow rates ranging from 0 to 25 sccm with a fixed argon gas flow rate of 15 sccm. Various H{sub n}{sup +}, SiH{sub n}{sup +}, SiH{sub n} fragments (with n = 1, 2, 3) together with Ar{sup +} and ArH{sup +} species are detected in the discharge. The most important species for the film deposition is SiH{sub n} (with n = 0, 1, 2). H fragments affect the hydrogen content in the material. The flux of Ar{sup +} decreases and the flux of ArH{sup +} increases when the hydrogen flow rate is increased; however, both fluxes saturate at hydrogen flow rates above 15 sccm. Electron density, n{sub e}, electron energy, T{sub e}, and ion density, n{sub i}, are estimated from the Langmuir probe data. T{sub e} is below 1.2 eV at hydrogen flow rates below 8 sccm, and about 2 eV at flow rates above 8 sccm. n{sub e} and n{sub i} decrease with increased hydrogen flow but the ratio of n{sub i} to n{sub e} increases. The formation of H{sup +} ions with energies above 36 eV and electrons with energies greater than 2 eV contributes to the decrease in hydrogen content at hydrogen flow rates above 8 sccm. Analysis of the IEDs indicates an inter-dependence of the species and their contribution to the thin film growth and properties.

Mensah, S. L.; Naseem, Hameed H. [University of Arkansas, Fayetteville, Arkansas 72701 (United States); Abu-Safe, Husam [Lebanese American University, Byblos (Lebanon); Gordon, M. H. [University of Denver, 2390 S. York St., Colorado 80208 (United States)

2012-07-15T23:59:59.000Z

344

Applications of Diagnostic X-ray Spectrometers  

Science Conference Proceedings (OSTI)

... produced plasmas, terawatt pulsed accelerators, electron cyclotron resonance ion sources, electron-beam ion traps, intense ultrafast laser sources ...

2012-06-26T23:59:59.000Z

345

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

346

NIST Calibration of a Neutron Spectrometer ROSPEC  

Science Conference Proceedings (OSTI)

... factors [11]. ROSPEC was used to measure 2.5 MeV (deuterium- deuterium) and 14 MeV (deuterium-tritium) neutrons. As ...

2006-12-06T23:59:59.000Z

347

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 ...

348

The Aerodynamic, Dual- Wavelength Optical Spectrometer  

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

Determination of Real and Imaginary Refractive Indices, Diameter and Density with a Compact Instrument (A-DWOPS) * DWOPS: Two Wavelengths, Two Angles. - A. Nagy, W.W. Szymanski,...

349

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

350

Filter-Analyzer Neutron Spectrometer (FANS)  

Science Conference Proceedings (OSTI)

... Soc., Div. Fuel Chem ... H. Kabbour, and CC Ahn, "Hydrogen Adsorption in MOF-74 Studied by Inelastic Neutron Scattering", in Life Cycle Analysis for ...

351

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

352

Lead Slowing Down Spectrometer Research Plans  

Science Conference Proceedings (OSTI)

The MPACT-funded Lead Slowing Down Spectrometry (LSDS) project has been evaluating the feasibility of using LSDS techniques to assay fissile isotopes in used nuclear fuel assemblies. The approach has the potential to provide considerable improvement in the assay of fissile isotopic masses in fuel assemblies compared to other non-destructive techniques in a direct and independent manner. The LSDS collaborations suggests that the next step to in empirically testing the feasibility is to conduct measurements on fresh fuel assemblies to understand investigate self-attenuation and fresh mixed-oxide (MOX) fuel rodlets so we may betterto understand extraction of masses for 235U and 239Pu. While progressing toward these goals, the collaboration also strongly suggests the continued development of enabling technology such as detector development and algorithm development, thatwhich could provide significant performance benefits.

Warren, Glen A.; Kulisek, Jonathan A.; Gavron, Victor; Danon, Yaron; Weltz, Adam; Harris, Jason; Stewart, T.

2013-03-22T23:59:59.000Z

353

NIST SURF Beamline 2: Spectrometer Calibrations  

Science Conference Proceedings (OSTI)

... irradiance; First experimental station is located 11.6 m from the tangent point (2 gimbals mounted on a milling table); Class ...

2011-10-03T23:59:59.000Z

354

Two-dimensional fourier transform spectrometer  

SciTech Connect

The present invention relates to a system and methods for acquiring two-dimensional Fourier transform (2D FT) spectra. Overlap of a collinear pulse pair and probe induce a molecular response which is collected by spectral dispersion of the signal modulated probe beam. Simultaneous collection of the molecular response, pulse timing and characteristics permit real time phasing and rapid acquisition of spectra. Full spectra are acquired as a function of pulse pair timings and numerically transformed to achieve the full frequency-frequency spectrum. This method demonstrates the ability to acquire information on molecular dynamics, couplings and structure in a simple apparatus. Multi-dimensional methods can be used for diagnostic and analytical measurements in the biological, biomedical, and chemical fields.

DeFlores, Lauren; Tokmakoff, Andrei

2013-09-03T23:59:59.000Z

355

NIST: N42-2011 Simple Spectrometer  

Science Conference Proceedings (OSTI)

... The definition of the radiation detector, a Nal scintillator, via . The energy calibration used by the radiation detector, ...

2012-04-09T23:59:59.000Z

356

CEBAF Large Acceptance Spectrometer (CLAS) Physics Database  

DOE Data Explorer (OSTI)

A username and password are required to access and search the entire database. However, the Overview page provides links to detailed data pages for each of the experiments available for public access. There are 44 experiments with data that the public can freely access.

None

357

Superconducting Tunnel Junctions X-ray Spectrometer  

The high energy resolution combined with the high count rate capabilities and high quantum efficiency of STJ detectors greatly enhance the sensitivity ...

358

Filter-Analyzer Neutron Spectrometer (FANS)  

Science Conference Proceedings (OSTI)

... J. Hwang, "Probing the Unusual Proton and Anion Mobility of LiBH ... Analysis of the Inelastic Neutron Scattering Spectra of Electron Donor-Acceptor ...

359

Raindrop Velocity Spectrometer for Drop Chemistry Investigations  

Science Conference Proceedings (OSTI)

The design of an instrument that sorts raindrops according to fall speed is described. The apparatus consists of two rotating disks, the upper one allowing rain to fall through a slit into collectors on the lower disk. Drops are collected in a ...

S. G. Bradley

1985-06-01T23:59:59.000Z

360

Pulsed Ionization Source for Ion Mobility Spectrometers  

ORNL’s new wave of detection devices based on ion mobility spectrometry offer enhanced sensitivity and resolution and increased safety and ...

Note: This page contains sample records for the topic "angular-range chopper 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

NIST Continuous-wave terahertz spectrometer  

Science Conference Proceedings (OSTI)

... Power detection sensitivity of the bolometer is lines (?? FWHM ? 0.2 cm -1 ) illustrate the scan ...

2012-10-18T23:59:59.000Z

362

NIST Wavenumbers for Calibration of IR Spectrometers  

Science Conference Proceedings (OSTI)

... band. Data from these complementary techniques include the best Fourier transform measurements available. The bibliography ...

2011-12-09T23:59:59.000Z

363

Sandia National Laboratories Miniaturized Mass Spectrometer  

subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration. SAND # 2011-4872P TECHNOLOGY ...

364

2004 Yerkes Summer Institute You are the Spectrometer! Lab 1 You Are the Spectrometer!  

E-Print Network (OSTI)

be interested in and learn about by studying this radiation? The light we can see with our eyes from light bulbs-rays, gamma rays, radio waves or microwaves. What makes visible light from a light bulb different than the x energy than visible light. This is also why x-rays can be dangerous to people. The ordering of radiation

Collar, Juan I.

365

Sample Environment Equipment Categories - ORNL Neutron Sciences  

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

Home › Instruments › Sample Environment Home › Instruments › Sample Environment Sample Environment: Categories of Equipment All Ancillary Equipment Auto Changer Closed Cycle Refrigerators Closed Cycle Refrigerators - Bottom Loading Closed Cycle Refrigerators - Top Loading Furnaces Gas Handling Gas Panel High Pressure Systems Liquid Helium Cryostats Magnet Systems Other Special Environments Sample Cell Sample Stick Ultra Low Temperature Devices Sample Environment: by Beam Line All BL-11A-POWGEN BL-11B-MANDI BL-12-TOPAZ BL-13-Fundamental Neutron Physics Beam Line BL-14A-BL-14A BL-14B-HYSPEC BL-15-Neutron Spin Echo (NSE) BL-16B-VISION BL-17-SEQUOIA BL-18-ARCS BL-1A-TOF-USANS BL-1B-NOMAD BL-2-BASIS BL-3-SNAP BL-4A-Magnetism Reflectometer BL-4B-Liquids Reflectometer BL-5-Cold Neutron Chopper Spectrometer (CNCS) BL-6-EQ-SANS

366

Dynamics of the fast component of nano-confined water under electric field  

E-Print Network (OSTI)

We report the diffusion of water molecules confined in the pores of folded silica materials (FSM-12 with average pore diameter of $\\sim$ 16 \\AA), measured by means of quasielastic neutron scattering using the cold neutron chopper spectrometer (CNCS). The goal is to investigate the effect of electric field on the previously observed fast component of nano-confined water. The measurements were taken at temperatures between 220 K and 245 K, and at two electric field values, 0 kV/mm and 2 kV/mm. Similar to the recently observed electric field induced enhancement of the slow translational motion of confined water, there is a an equally important impact of the field on the faster diffusion.

S. O. Diallo; E. Mamontov; A. Podlesnyak; G. Ehlers; N. Wada; S. Inagaki; Y. Fukushima

2013-06-27T23:59:59.000Z

367

Dynamics of the fast component of nano-confined water under electric field  

Science Conference Proceedings (OSTI)

We report the diffusion of water molecules confined in the pores of folded silica materials (FSM-12 with average pore diameter of $\\sim$ 16 \\AA), measured by means of quasielastic neutron scattering using the cold neutron chopper spectrometer (CNCS). The goal is to investigate the effect of electric field on the previously observed fast component of nano-confined water. The measurements were taken at temperatures between 220 K and 245 K, and at two electric field values, 0 kV/mm and 2 kV/mm. Similar to the recently observed electric field induced enhancement of the slow translational motion of confined water, there is a an equally important impact of the field on the faster diffusion.

Omar Diallo, Souleymane [ORNL; Mamontov, Eugene [ORNL; Podlesnyak, Andrey A [ORNL; Ehlers, Georg [ORNL; Wada, Nobuo [Nagoya University, Japan; Inagaki, S [Toyota Central Research and Development Labs. Inc.; Fukushima, Y [Toyota Central Research and Development Labs. Inc.

2013-01-01T23:59:59.000Z

368

pi+- p differential cross sections at low energies  

Science Conference Proceedings (OSTI)

Differential cross sections for pi- p and pi+ p elastic scattering were measured at five energies between 19.9 and 43.3 MeV. The use of the CHAOS magnetic spectrometer at TRIUMF, supplemented by a range telescope for muon background suppression, provided simultaneous coverage of a large part of the full angular range, thus allowing very precise relative cross section measurements. The absolute normalization was determined with a typical accuracy of 5 %. This was verified in a simultaneous measurement of muon proton elastic scattering. The measured cross sections show some deviations from phase shift analysis predictions, in particular at large angles and low energies. From the new data we determine the real part of the isospin forward scattering amplitude.

H. Denz; P. Amaudruz; J.T. Brack; J. Breitschopf; P. Camerini; J.L. Clark; H. Clement; L. Felawka; E. Fragiacomo; E.F. Gibson; N. Grion; G.J. Hofman; B. Jamieson; E.L. Mathie; R. Meier; G. Moloney; D. Ottewell; O. Patarakin; J.D. Patterson; M.M. Pavan; S. Piano; K. Raywood; R.A. Ristinen; R. Rui; M.E. Sevior; G.R. Smith; J. Stahov; R. Tacik; G.J. Wagner; F. von Wrochem; D.M. Yeomans

2005-12-03T23:59:59.000Z

369

Moisture Analysis from Radiosonde and Microwave Spectrometer Data  

Science Conference Proceedings (OSTI)

A method for analysis of the horizontal and vertical distributions of the moisture field utilizing satellite, upper air and surface data is proposed in this paper. A brief overview of the microwave sensors on board Nimbus 5 and 6 is also ...

Kenneth J. Haydu; T. N. Krishnamurti

1981-10-01T23:59:59.000Z

370

Development of a chemical vision spectrometer to detect chemical agents.  

DOE Green Energy (OSTI)

This paper describes initial work in developing a no-moving-parts hyperspectral-imaging camera that provides both a thermal image and specific identification of chemical agents, even in the presence of nontoxic plumes. The camera uses enhanced stand-off chemical agent detector (ESCAD) technology based on a conventional thermal-imaging camera interfaced with an acousto-optical tunable filter (AOTF). The AOTF is programmed to allow selected spectral frequencies to reach the two dimensional array detector. These frequencies are combined to produce a spectrum that is used for identification. If a chemical agent is detected, pixels containing the agent-absorbing bands are given a colored hue to indicate the presence of the agent. In test runs, two thermal-imaging cameras were used with a specially designed vaporizer capable of controlled low-level (low ppm-m) dynamic chemical releases. The objective was to obtain baseline information about detection levels. Dynamic releases allowed for realistic detection scenarios such as low sky, grass, and wall structures, in addition to reproducible laboratory releases. Chemical releases consisted of dimethylmethylphosphonate (DMMP) and methanol. Initial results show that the combination of AOTF and thermal imaging will produce a chemical image of a plume that can be detected in the presence of interfering substances.

Demirgian, J.

1999-02-23T23:59:59.000Z

371

The high-flux backscattering spectrometer at the NIST Center ...  

Science Conference Proceedings (OSTI)

... selector mount and neutron shutter, and IG Schröder neutron guides and shielding; Electrical: B. Dickerson PLC system, D. Kulp, T. Thai, and J ...

2011-04-18T23:59:59.000Z

372

HD gas analysis with Gas Chromatography and Quadrupole Mass Spectrometer  

E-Print Network (OSTI)

A gas analyzer system has been developed to analyze Hydrogen-Deuteride (HD) gas for producing frozen-spin polarized HD targets, which are used for hadron photoproduction experiments at SPring-8. Small amounts of ortho-H$_{2}$ and para-D$_{2}$ gas mixtures ($\\sim$0.01%) in the purified HD gas are a key to realize a frozen-spin polarized target. In order to obtain reliable concentrations of these gas mixtures in the HD gas, we produced a new gas analyzer system combining two independent measurements with the gas chromatography and the QMS. The para-H$_{2}$, ortho-H$_{2}$, HD, and D$_{2}$ are separated using the retention time of the gas chromatography and the mass/charge. It is found that the new gas analyzer system can measure small concentrations of $\\sim$0.01% for the otho-H$_2$ and D$_2$ with good S/N ratios.

T. Ohta; S. Bouchigny; J. -P. Didelez; M. Fujiwara; K. Fukuda; H. Kohri; T. Kunimatsu; C. Morisaki; S. Ono; G. Rouille; M. Tanaka; K. Ueda; M. Uraki; M. Utsuro; S. Y. Wang; M. Yosoi

2011-01-28T23:59:59.000Z

373

SPEC-DOC: A USER'S GUIDE TO SPECTROMETER SOFTWARE  

E-Print Network (OSTI)

Press button on the EIA/TTL toggle box labeled "Micro-P/P/Aux, Nova/Main" on EIA/TTL box. Toggle CONTINUE on theIf you are not using the EIA/TTL toggle box: Make sure that

Sinton, S.

2008-01-01T23:59:59.000Z

374

Infrared Intracavity Laser Absorption Spectrometer , A. V. Muravjovb  

E-Print Network (OSTI)

Spectroscopy (ICLAS) at Mid-IR (MIR, 3-5 µm wavelengths), Long-Wave IR (LWIR, 8-12 µm wavelengths of vapors that will be simple, low-power, man portable, and composed of all off-the-shelf components aerosols, drugs, and banned or invasive plants or animals. Also, biomedical breath analysis and non

Peale, Robert E.

375

Synchrotron plus Mass Spectrometer equals New Insights Into Combustion...  

Office of Science (SC) Website

Unique analysis of the reaction of propene with oxygen atom reveals the influence of electron spin on combustion chemistry. Print Text Size: A A A Subscribe FeedbackShare Page...

376

High resolution, high rate x-ray spectrometer  

DOE Patents (OSTI)

It is an object of the invention to provide a pulse processing system for use with detected signals of a wide dynamic range which is capable of very high counting rates, with high throughput, with excellent energy resolution and a high signal-to-noise ratio. It is a further object to provide a pulse processing system wherein the fast channel resolving time is quite short and substantially independent of the energy of the detected signals. Another object is to provide a pulse processing system having a pile-up rejector circuit which will allow the maximum number of non-interfering pulses to be passed to the output. It is also an object of the invention to provide new methods for generating substantially symmetrically triangular pulses for use in both the main and fast channels of a pulse processing system.

Goulding, F.S.; Landis, D.A.

1983-07-14T23:59:59.000Z

377

Vertical Resolution and Accuracy of Atmospheric Infrared Sounding Spectrometers  

Science Conference Proceedings (OSTI)

A theoretical analysis is performed to evaluate the accuracy and vertical resolution of atmospheric profiles obtained with the HIRS/2, GOES I/M, and HIS instruments. In addition, a linear simultaneous retrieval algorithm is used with aircraft ...

Hung-Lung Huang; William L. Smith; Harold M. Woolf

1992-03-01T23:59:59.000Z

378

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

379

Direction-Sensitive Hand-Held Gamma-Ray Spectrometer  

SciTech Connect

A novel, light-weight, hand-held gamma-ray detector with directional sensitivity is being designed. The detector uses a set of multiple rings around two cylindrical surfaces, which provides precise location of two interaction points on two concentric cylindrical planes, wherefrom the source location can be traced back by back projection and/or Compton imaging technique. The detectors are 2.0 × 2.0 mm europium-doped strontium iodide (SrI2:Eu2+) crystals, whose light output has been measured to exceed 120,000 photons/MeV, making it one of the brightest scintillators in existence. The crystal’s energy resolution, less than 3% at 662 keV, is also excellent, and the response is highly linear over a wide range of gamma-ray energies. The emission of SrI2:Eu2+ is well matched to both photo-multiplier tubes and blue-enhanced silicon photodiodes. The solid-state photomultipliers used in this design (each 2.0 × 2.0 mm) are arrays of active pixel sensors (avalanche photodiodes driven beyond their breakdown voltage in reverse bias); each pixel acts as a binary photon detector, and their summed output is an analog representation of the total photon energy, while the individual pixel accurately defines the point of interaction. A simple back-projection algorithm involving cone-surface mapping is being modeled. The back projection for an event cone is a conical surface defining the possible location of the source. The cone axis is the straight line passing through the first and second interaction points.

Mukhopadhyay, S.

2012-10-04T23:59:59.000Z

380

Field-portable mass spectrometers for onsite analytics: What's next?  

Science Conference Proceedings (OSTI)

The need for rapid, onsite chemical analyses is as apparent as it has ever been, especially for compounds detrimental to health or to the environment, such as toxic industrial species, explosives, chemical warfare agents, and environmental toxins. Field-po

Note: This page contains sample records for the topic "angular-range chopper 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.


381

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

382

Spectrometer employing optical fiber time delays for frequency resolution  

DOE Patents (OSTI)

This invention provides different length glass fibers for providing a broad range of optical time delays for short incident chromatic light pulses for the selective spatial and frequency analysis of the light with a single light detector. To this end, the frequencies of the incident light are orientated and matched with the different length fibers by dispersing the separate frequencies in space according to the respective fiber locations and lengths at the input terminal of the glass fibers. This makes the different length fibers useful in the field of plasma physics. To this end the short light pulses can be scattered by a plasma and then passed through the fibers for analyzing and diagnosing the plasma while it varies rapidly with time.

Schuss, Jack J. (Providence, RI); Johnson, Larry C. (Princeton, NJ)

1979-01-01T23:59:59.000Z

383

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

384

Lead Slowing Down Spectrometer FY2013 Annual Report  

SciTech Connect

Executive Summary The Lead Slowing Down Spectrometry (LSDS) project, funded by the Materials Protection And Control Technology campaign, has been evaluating the feasibility of using LSDS techniques to assay fissile isotopes in used nuclear fuel assemblies. The approach has the potential to provide considerable improvement in the assay of fissile isotopic masses in fuel assemblies compared to other non-destructive techniques in a direct and independent manner. This report is a high level summary of the progress completed in FY2013. This progress included: • Fabrication of a 4He scintillator detector to detect fast neutrons in the LSDS operating environment. Testing of the detector will be conducted in FY2014. • Design of a large area 232Th fission chamber. • Analysis using the Los Alamos National Laboratory perturbation model estimated the required number of neutrons for an LSDS measurement to be 10 to the 16th source neutrons. • Application of the algorithms developed at Pacific Northwest National Laboratory to LSDS measurement data of various fissile samples conducted in 2012. The results concluded that the 235U could be measured to 2.7% and the 239Pu could be measured to 6.3%. Significant effort is yet needed to demonstrate the applicability of these algorithms for used-fuel assemblies, but the results reported here are encouraging in demonstrating that we are making progress toward that goal. • Development and cost-analysis of a research plan for the next critical demonstration measurements. The plan suggests measurements on fresh fuel sub assemblies as a means to experimentally test self-attenuation and the use of fresh mixed-oxide fuel as a means to test simultaneous measurement of 235U and 239Pu.

Warren, Glen A.; Kulisek, Jonathan A.; Gavron, Victor A.; Danon, Yaron; Weltz, Adam; Harris, Jason; Stewart, T.

2013-10-29T23:59:59.000Z

385

Spectrometer capillary vessel and method of making same  

DOE Patents (OSTI)

The present invention is an arrangement of a glass capillary tube for use in spectroscopy. In particular, the invention is a capillary arranged in a manner permitting a plurality or multiplicity of passes of a sample material through a spectroscopic measurement zone. In a preferred embodiment, the multi-pass capillary is insertable within a standard NMR sample tube. The present invention further includes a method of making the multi-pass capillary tube and an apparatus for spinning the tube.

Linehan, John C. (Richland, WA); Yonker, Clement R. (Kennewick, WA); Zemanian, Thomas S. (Richland, WA); Franz, James A. (Kennewick, WA)

1995-01-01T23:59:59.000Z

386

HYSPEC: the Hybrid Spectrometer at SNS - ORNL Neutron Sciences  

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

Documentation for HYSPEC Documents HYSPEC Status June, 22 2012 HYSPEC Status, May 21, 2012 HYSPEC Status Mar, 29 2012 HYSPEC Status Feb, 28 2012 HYSPEC Status Feb, 5 2013 HYSPC...

387

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...

388

Mass Spectrometer for High Molecular Weight Ions and Charged Particles  

APPLICATIONS OF TECHNOLOGY: Biotechnology ; Structural biology ; Materials science studies of nanoparticles ; ADVANTAGES:

389

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

390

Spectrometer capillary vessel and method of making same  

DOE Patents (OSTI)

The present invention is an arrangement of a glass capillary tube for use in spectroscopy. In particular, the invention is a capillary arranged in a manner permitting a plurality or multiplicity of passes of a sample material through a spectroscopic measurement zone. In a preferred embodiment, the multi-pass capillary is insertable within a standard NMR sample tube. The present invention further includes a method of making the multi-pass capillary tube and an apparatus for spinning the tube. 13 figs.

Linehan, J.C.; Yonker, C.R.; Zemanian, T.S.; Franz, J.A.

1995-11-21T23:59:59.000Z

391

Comparisons of the DSPEC and DSPEC Plus spectrometer systems  

SciTech Connect

A previous experimental evaluation of nine commercial gamma-ray spectroscopy systems demonstrated significant benefits of digital signal processing for improvements in the performance of high-resolution gamma-ray spectroscopy systems. Spectacular improvements in the energy resolution and throughput of germanium detectors were demonstrated for the DSPEC. Recently, a new, improved version of DSPEC, the DSPEC Plus, was developed. Results of the performance of the DSPEC Plus are compared to those of the DSPEC.

Duc T. Vo

1999-11-01T23:59:59.000Z

392

Wide Size Range Fast Integrated Mobility Spectrometer - Energy ...  

The conduit includes a separator section configured to generate an electrical field of two dimensions transverse to a ... Brookhaven Science Associates, LLC

393

Design of a Mid-infrared Cavity Ring Down Spectrometer  

E-Print Network (OSTI)

) for LCD applications, but in recent years a lot of interest has been going out to the solar cells that can be produced with it. a-Si:H solar cells Solar cells based on amorphous silicon consist of a stack of thin the cell through the glass, and converts the photon energy into free electron-hole pairs. An n-type and p

Eindhoven, Technische Universiteit

394

OPTIMIZATION OF THE HYSPEC DESIGN USING MONTE CARLO SIMULATIONS.  

DOE Green Energy (OSTI)

HYSPEC is a direct geometry spectrometer to be installed at the SNS [1] on beamline 14B where it will view a cryogenic coupled hydrogen moderator, The ''hybrid'' design combines time-of-flight spectroscopy with focusing Bragg optics to provide a high monochromatic flux on small single crystal samples, with a very low background at an extended detector bank. The instrument is optimized for an incident energy range of 3-90meV. It will have a medium energy resolution (2-10%) and will provide a flux on sample of the order of 10{sup 6}-10{sup 7} neutrons/s-cm{sup 2}. The spectrometer will be located in a satellite building outside the SNS experimental hall at the end of a 35m curved supermirror guide. A straight-slotted Fermi chopper will be used to monochromate the neutron beam and to determine the burst width. The 15cm high, 4cm wide beam will be focused onto a 2cm by 2cm area at the sample position using Bragg reflection from one of two crystal arrays. For unpolarized neutron studies these will be Highly Oriented Pyrolitic graphite crystals while for polarized neutron studies these will be replaced with Heusler alloy crystals. These focusing crystal arrays will be placed in a drum shield similar to those used for triple axis spectrometers. Hyspec will have a movable detector bank housing 160 position sensitive detectors. This detector bank will pivot about the sample axis. It will have a radius of 4.5m, a horizontal range of 60{sup o}, and a vertical range of {+-} 7.5{sup o}. In order to reduce background at the detector bank both a curved guide and a T0 chopper will be used. A bank of 20 supermirror bender polarization analyzers [2] will be used to spatially separate the polarized neutrons in the scattered beam so that both scattered neutron spin states can be measured simultaneously. The results of Monte Carlo simulations performed to optimize the instrument design will be discussed.

GHOSH, V.J.; HAGEN, M.E.; LEONHARDT, W.J.; ZALIZNYAK, I.; SHAPIRO, S.M.; PASSELL, L.

2005-04-25T23:59:59.000Z

395

Pion inelastic scattering from sup 20 Ne  

SciTech Connect

Angular distributions for {sup 20}Ne({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime}) were measured on the Energetic Pion Channel and Spectrometer (EPICS) at the Clinton P. Anderson Meson Physics Facility (LAMPF). Data were taken with both {pi}{sup {plus}} and {pi}{sup {minus}} over an angular range of 12{degree} to 90{degree} for T{sub {pi}}=180 MeV and with {pi}{sup +} from 15{degree} to 90{degree} for T{sub {pi}}=120 MeV. The data were analyzed using both the distorted-wave impulse approximation (DWIA) and the coupled-channels impulse approximation (CCIA) with collective transition densities. In addition, microscopic transition densities were used in the DWIA analysis for states in the lowest rotational bands. The transitions to the 6.73-MeV 0{sup +} and several 1{sup {minus}} states, including the states at 5.79 MeV and 8.71 MeV, were studied using several models for the transition density. Strong evidence for the importance of two-step routes in pion inelastic scattering was seen in several angular distributions, including the 5.79-MeV 1{sup {minus}}, the first three 4{sup +} states, and the 8.78-MeV 6{sup +}. 100 refs., 81 figs., 33 tabs.

Burlein, M. (Pennsylvania Univ., Philadelphia, PA (USA). Dept. of Physics)

1989-12-01T23:59:59.000Z

396

Strangeness electroproduction on the nucleon at CLAS  

Science Conference Proceedings (OSTI)

High-precision measurements of strange particle production from both proton and neutron targets are a core part of the physics program with the CLAS spectrometer in Hall B at Jefferson Laboratory. Measurements have been carried out at beam energies up to 6 GeV in experiments with polarized beams and polarized targets. This talk will focus on the electroproduction measurements that have been completed, which include cross sections and hyperon polarization observables for K{sup +}Y (Y = {Lambda}{Sigma}{sup 0}) final states over a broad kinematic range in momentum transfer Q{sup 2} and invariant energy W, while spanning nearly the full kaon center-of-mass angular range. These data in the strangeness sector are necessary to better understand the different production mechanisms for {Lambda} and {Sigma} hyperons and to disentangle the different resonant and non-resonant amplitudes in the intermediate state. The usefulness of the CLAS electroproduction data as part of a coupled-channel model fit will be discussed as well as an outlook of this program for the future.

Daniel Carman

2012-04-01T23:59:59.000Z

397

Neutron Compound Refractive Prisms - DOE SBIR Phase II Final Report  

SciTech Connect

The results of the research led to a pulsed electromagnetic periodic magnetic field array (PMF), which coupled with a pair of collimation slits, and a mechanical chopper slit, were able to deflect spin-up neutrons to a band of line-fused neutrons a focal plane heights that correspond to the time-varying magnetic field amplitude. The electromagnetic field PMF produced 5.4 pulses per minute in which each pulse was 50 msec in duration with a full width half maximum (FWHM) of 7.5 msec. The calculated 7.7 mm vertical height of the band of focused spin-up neutrons corresponded closely to the measured 7.5 mm height of the center line of the imaged band of neutrons. The band of deflected spin-up neutrons was 5 mm in vertical width and the bottom of the band was 5 mm above the surface of the PMF pole. The limited exposure time of 3 hours and the smaller 0.78 T magnetic field allowed focused and near focused neutrons of 1.8 ���� to 2.6 ���� neutrons, which were in the tails of the McClellan Nuclear Radiation Center Bay 4 Maxwell Boltzmann distribution of neutrons with peak flux at 1.1-1.2 ����. The electromagnetic PMF was expected to produces a 2.0 T peak magnetic field amplitude, which would be operational at a higher duty factor, rather than the as built 7.5 msec FWHM with pulse repetition frequency of 5.4 pulses per minute. The fabricated pulsed electromagnetic PMF with chopper is expected to perform well on a cold, very cold or ultra cold beam line as a spectrometer or monochromator source of spin-up polarized neutron. In fact there may be a possible use of the PMF to do ultra-cold neutron trapping, see paper by A. I. Frank1, V. G. Nosov, Quantum Effects in a One-Dimensional Magnetic Gravitational Trap for Ultracold Neutrons, JETP Letters, Vol. 79, No. 7, 2004, pp. 313�¢����315. The next step is to find a cold or very cold neutron facility, where further testing or use of the pulsed magnetic field PMF can be pursued.

Dr. Jay Theodore Cremer, Jr

2011-06-25T23:59:59.000Z

398

Total Absorption Gamma-ray Spectrometer (TAGS) Simulations with GEANT4  

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

ANL/NDM-16 ANL/NDM-16 Nuclear Data and Measurements Series Nuclear Engineering Division Availability of This Report This report is available, at no cost, at http://www.osti.gov/bridge. It is also available on paper from the U.S. Department of Energy and its contractors, for a processing fee, from: U.S. Department of Energy P.O. Box 62 Oak Ridge, TN 37831-0062 phone (865) 576-8401 fax (865) 576-5728 reports@adonis.osti.gov Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States

399

Evaluation of Technologies to Complement/Replace Mass Spectrometers in the Tritium Facilities  

DOE Green Energy (OSTI)

The primary goal of this work is to determine the suitability of the Infraran sensor for use in the Palladium Membrane Reactor. This application presents a challenge for the sensor, since the process temperature exceeds its designed operating range. We have demonstrated that large baseline offsets, comparable to the sensor response to the analyte, are obtained if cool air is blown across the sensor. We have also shown that there is a strong environmental component to the noise. However, the current arrangement does not utilize a reference detector. The strong correlation between the CO and H{sub 2}O sensor responses to environmental changes indicate that a reference detector can greatly reduce the environmental sensitivity. In fact, incorporation of a reference detector is essential for the sensor to work in this application. We have also shown that the two sensor responses are adequately independent. Still, there are several small corrections which must to be made to the sensor response to accommodate chemical and physical effects. Interactions between the two analytes will alter the relationship between number density and pressure. Temperature and pressure broadening will alter the relationship between absorbance and number density. The individual effects are small--on the order of a few percent or less--but cumulatively significant. Still, corrections may be made if temperature and total pressure are independently measured and incorporated into a post-analysis routine. Such corrections are easily programmed and automated and do not represent a significant burden for installation. The measurements and simulations described above indicate that with appropriate corrections, the Infraran sensor can approach the 1-1.5% measurement accuracy required for effective PMR process control. It is also worth noting that the Infraran may be suitable for other gas sensing applications, especially those that do not need to be made in a high-temperature environment. Any gas with an infrared absorption (methane, ammonia, etc.) may be detected so long as an appropriate bandpass filter can be manufactured. Note that homonuclear diatomic molecules (hydrogen and its isotopes, nitrogen, oxygen) do not have infrared absorptions. We have shown that the sensor response may be adequately predicted using commercially available software. Measurement of trace concentrations is limited by the broad spectral bandpass, since the total signal includes non-absorbed frequencies. However, cells with longer pathlengths can be designed to address this problem.

Tovo, L. L.; Lascola, R. J.; Spencer, W. A.; McWhorter, C. S.; Zeigler, K. E.

2005-08-30T23:59:59.000Z

400

ITER Core Imaging X-Ray Spectrometer Conceptual Design and Performance Assessment - Phase 2  

SciTech Connect

During Phase 2 of our study of the CIXS conceptual design we have tackled additional important issues that are unique to the ITER environment. These include the thermal control of the crystal and detector enclosures located in an environment with a 100-250 C ambient temperature, tritium containment, and the range of crystal and detector movement based on the need for spectral adjustments and the desire to make measurements of colder plasmas. In addressing these issues we have selected a ''Dewar''-type enclosure for the crystals and detectors. Applying realistic view factors for radiant heat and making allowance for conduction we have made engineering studies of this enclosure and showed that the cooling requirements can be solved and the temperature can be kept sufficiently constant without compromising the specification parameters of the CIXS. We have chosen a minimum 3 mm combined thickness of the six beryllium windows needed in a Dewar-type enclosure and showed that a single window of 0.5 mm thickness satisfies tritium containment requirements. For measuring the temperature in cooler ITER plasmas, we have chosen to use the K-shell lines of Fe24+. Iron is the preferred choice because its radiation can be analyzed with the identical CIXS settings used for analyzing the tungsten radiation, i.e., essentially no adjustments besides a simple crystal rotation need to be made. We have, however, included an xy{theta}-drive motor arrangement in our design for fine adjustments and full rotation of the crystal mounts.

Beiersdorfer, P; Wen, J; Dunn, J; Morris, K

2011-01-02T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

Improved Drop Generators for Calibration of Drop Spectrometers and Use in Laboratory Cloud Physics Experiments  

Science Conference Proceedings (OSTI)

Drop generators have been developed at NCAR based on the “wire egression” principle. They are outstanding in their flexibility and simplicity. Drops ranging in diameter from 6 ?m to 1 mm have been generated with one model. Application of the ...

Theodore W. Cannon; Walter W. Grotewold

1980-07-01T23:59:59.000Z

402

Comparison of Infrared Atmospheric Brightness Temperatures Measured by a Fourier Transform Spectrometer and a Filter Radiometer  

Science Conference Proceedings (OSTI)

Increased interest in using atmospheric brightness temperature measurements from simple infrared radiometers combined with radars and lidars has prompted the investigation of their accuracy for various sky conditions. In comparisons of ...

Joseph A. Shaw; Jack B. Snider; James H. Churnside; Mark D. Jacobson

1995-10-01T23:59:59.000Z

403

A laser-excited synchronous fluorescence spectrometer for benzo(a)pyrene  

Science Conference Proceedings (OSTI)

A laser-based synchronous scanning fluorimeter was developed for detecting polycyclic aromatic hydrocarbons (PAHs). Although extensive sample cleanup and separation are usually required, fluorescence has long been used for determination of PAHs. Amount of sample pretreatment can often be reduced when synchronous fluorescence (SF) is used, and the sensitivity of SF can be increased by the high power and narrow profile of a laser source. A small, portable, pulsed dye laser was used in this study. The instrument and its application to the determination of the carcinogen benzo(a)pyrene are described.

Huebedr, D.M.; Iruela Del Olmo, M.; Stevenson, C.L.; Vo-Dinh, T.

1995-09-01T23:59:59.000Z

404

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

405

The Prospect for Remote Sensing of Cirrus Clouds with a Submillimeter-Wave Spectrometer  

Science Conference Proceedings (OSTI)

Given the substantial radiative effects of cirrus clouds and the need to validate cirrus cloud mass in climate models, it is important to measure the global distribution of cirrus properties with satellite remote sensing. Existing cirrus remote ...

K. Franklin Evans; Aaron H. Evans; Ira G. Nolt; B. Thomas Marshall

1999-05-01T23:59:59.000Z

406

Electro-optically modulated polarizing Fourier-transform spectrometer for plasma  

E-Print Network (OSTI)

-integrated emis- The author is with the Plasma Research Laboratory, Australian National University, Canberra

Howard, John

407

Chemical ionization tandem mass spectrometer for the in situ measurement of methyl hydrogen peroxide  

SciTech Connect

A new approach for measuring gas-phase methyl hydrogen peroxide [(MHP) CH{sub 3}OOH] utilizing chemical ionization mass spectrometry is presented. Tandem mass spectrometry is used to avoid mass interferences that hindered previous attempts to measure atmospheric CH{sub 3}OOH with CF{sub 3}O{sup -} clustering chemistry. CH{sub 3}OOH has been successfully measured in situ using this technique during both airborne and ground-based campaigns. The accuracy and precision for the MHP measurement are a function of water vapor mixing ratio. Typical precision at 500 pptv MHP and 100 ppmv H{sub 2}O is {+-}80 pptv (2 sigma) for a 1 s integration period. The accuracy at 100 ppmv H{sub 2}O is estimated to be better than {+-}40%. Chemical ionization tandem mass spectrometry shows considerable promise for the determination of in situ atmospheric trace gas mixing ratios where isobaric compounds or mass interferences impede accurate measurements.

St Clair, Jason M.; McCabe, David C. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125 (United States); Crounse, John D. [Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125 (United States); Steiner, Urs [Varian, Inc., Santa Clara, California 95051 (United States); Wennberg, Paul O. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125 (United States); Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125 (United States)

2010-09-15T23:59:59.000Z

408

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

409

Development of Superconducting High-Resolution Gamma-Ray Spectrometers for Nuclear Safeguards  

E-Print Network (OSTI)

Nuclear Safeguards and Non-Proliferation. ESARDA Bulletin,Cycles: Safeguards and Non-Proliferation. KIT Scientificnuclear attribution and non-proliferation applications. In

Dreyer, Jonathan

2012-01-01T23:59:59.000Z

410

Spectrometer for measuring the concentration of components in a fluid stream and method for using same  

DOE Patents (OSTI)

A device and method are described for measuring the concentrations of components of a fluid stream. Preferably, the fluid stream is an in-situ gas stream, such as a fossil fuel fired flue gas in a smoke stack. The measurements are determined from the intensity of radiation over a selected range of radiation wavelengths using peak-to-trough calculations. The need for a reference intensity is eliminated. 15 figures.

Durham, M.D.; Stedman, D.H.; Ebner, T.G.; Burkhardt, M.R.

1991-12-03T23:59:59.000Z

411

The Multiplexed Chemical Kinetic Photoionization Mass Spectrometer: A New Approach To Isomer-resolved Chemical Kinetics  

E-Print Network (OSTI)

instruments applied to analysis of complex chemical mixturesrelies on chemical separation (by chromatography) into pureThe multiplexed chemical kinetic photoionization mass

Osborne, David L.

2009-01-01T23:59:59.000Z

412

Study of few-nucleon systems with the CEBAF large acceptance spectrometer  

Science Conference Proceedings (OSTI)

The study of few-nucleon systems at intermediate energies is an important aspect of the nuclear-physics program carried out by the CLAS Collaboration at Jefferson Laboratory. Our investigations aim at understanding the nuclear dynamics at short distances, the transition from hadronic to partonic description of nuclei, and how nuclei can be described in the framework of Quantum Chromodynamics. Our data on photodisintegration of 3He and 4He at beam energies from 0.3 GeV to 1.5 GeV strongly favor theoretical calculations that include three-body mechanisms and indicate significant contributions of these mechanisms at large momentum transfer, especially in the range of photon energies from 0.6 GeV to 0.8 GeV. Our investigations of exclusive and inclusive electron scattering off nuclear targets have yielded the determination of the ratio of pp to pn correlated pairs in 3He and of the probabilities of short-range correlations in nuclei. We have studied the transition from hadronic to partonic dynamics in nuclear processes by searching for the onset of scaling of the invariant cross sections of photoinduced reactions on few-nucleon systems. Our data are consistent with scaling at momentum transfer as low as 1 (GeV/c)2

Yordanka Ilieva

2011-05-01T23:59:59.000Z

413

Measurements with the high flux lead slowing-down spectrometer at LANL  

E-Print Network (OSTI)

of 26.1-min 235m U, Phys. Rev. C 36 (1987) 1896. [4] A. D'Eer, C. Wagemans, M. Ne`ve de Me´vergnies, F

Danon, Yaron

414

Measurement of reactive and condensable gas permeation using a mass spectrometer  

Science Conference Proceedings (OSTI)

Permeation of water vapor, oxygen, nitrogen, and carbon dioxide through polymer films is measured by the programed valving mass spectrometry (PVMS) method. The results are calibrated with a standard permeation rate for each gas to determine the detection sensitivity. The calibrated lower detection limits are 1.90x10{sup -7} g/m{sup 2} day for water vapor, 2.81x10{sup -2} cm{sup 3}/m{sup 2} day for oxygen, 2.15x10{sup -2} cm{sup 3}/m{sup 2} day for nitrogen, and 3.29x10{sup -2} cm{sup 3}/m{sup 2} day for carbon dioxide. The lower detection limits presented here for water vapor, nitrogen, and carbon dioxide are more than two orders of magnitude lower than the corresponding values offered by the NIST-traceable standard techniques. In addition, the PVMS water vapor lower detection limit meets the sensitivity requirement for detecting 'ultrabarrier' water vapor permeation rates, while the oxygen lower detection limit is higher than that offered by the standard technique. However, the results suggest a modified measurement protocol and/or system modifications to overcome this limitation. Effusivity through a flow orifice was also examined using the PVMS method for the above gases. The effusion results from the flow orifice, combined with the permeation results from polymer samples, provide insight into the factors that may influence gas detection sensitivities.

Zhang Xiaodong; Lewis, Jay S.; Parker, Charles B.; Glass, Jeffrey T.; Wolter, Scott D. [Pratt School of Engineering, Duke University, Durham, North Carolina 27708 (United States); RTI International, Research Triangle Park, North Carolina 27709 (United States); Pratt School of Engineering, Duke University, Durham, North Carolina 27708 (United States)

2008-09-15T23:59:59.000Z

415

Detection of carbon monoxide (CO) as a furnace byproduct using a rotating mask spectrometer.  

Science Conference Proceedings (OSTI)

Sandia National Laboratories, in partnership with the Consumer Product Safety Commission (CPSC), has developed an optical-based sensor for the detection of CO in appliances such as residential furnaces. The device is correlation radiometer based on detection of the difference signal between the transmission spectrum of the sample multiplied by two alternating synthetic spectra (called Eigen spectra). These Eigen spectra are derived from a priori knowledge of the interferents present in the exhaust stream. They may be determined empirically for simple spectra, or using a singular value decomposition algorithm for more complex spectra. Data is presented on the details of the design of the instrument and Eigen spectra along with results from detection of CO in background N{sub 2}, and CO in N{sub 2} with large quantities of interferent CO{sub 2}. Results indicate that using the Eigen spectra technique, CO can be measured at levels well below acceptable limits in the presence of strongly interfering species. In addition, a conceptual design is presented for reducing the complexity and cost of the instrument to a level compatible with consumer products.

Sinclair, Michael B.; Flemming, Jeb Hunter; Blair, Raymond (Honeywell Federal Manufacturing & Technologies, Albuqueruque, NM); Pfeifer, Kent Bryant

2006-02-01T23:59:59.000Z

416

THE EFFECTS OF BETA-SPECTROMETER FOCUSING POWER ON THE END-WINDOW COUNTER EFFICIENCY  

SciTech Connect

The efficency dependence of end-window counters on specimen surface density at a relative solid angle 0.111 was determined with the aid of a 4 pi counter. The isotopes S/sup 35/, Cas/sup 45/, Co/sup 60/, Ce/sup 141/Tl/sup 204/ , and Y/sup 91/ were studied. (tr-auth)

Vasil' ev, I.A.; Petrazhak, K.A.

1959-01-01T23:59:59.000Z

417

Measurement of dissolved neon by isotope dilution using a quadrupole mass spectrometer  

E-Print Network (OSTI)

and finally air. A special technique for sealing in whichsealing end. ple times by reverse isotope dilution with air.

Hamme, Roberta C; Emerson, Steven R

2004-01-01T23:59:59.000Z

418

Development of Superconducting High-Resolution Gamma-Ray Spectrometers for Nuclear Safeguards  

E-Print Network (OSTI)

Against the Spread of Nuclear Weapons: IAEA Safeguards indetonation of the first nuclear weapon in the desert of Newby the pursuit of nuclear weapons by violent extremists and

Dreyer, Jonathan

2012-01-01T23:59:59.000Z

419

The CO2 Gas Cherenkov Detectors for the Je erson Lab Hall A Spectrometers  

E-Print Network (OSTI)

obtained by using a wavelength shifter coated on the photocathode glass window. With such an improvement and in the hadron arm, by combining the information coming from a silica aerogel Cherenkov counter 2,3 , a gas

420

Performance of the Two Aerogel Cherenkov Detectors of the JLab Hall A Hadron Spectrometer  

E-Print Network (OSTI)

We report on the design and commissioning of two silica aerogel Cherenkov detectors with different refractive indices. In particular, extraordinary performance in terms of the number of detected photoelectrons was achieved through an appropriate choice of PMT type and reflector, along with some design considerations. After four years of operation, the number of detected photoelectrons was found to be noticeably reduced in both detectors as a result of contamination, yellowing, of the aerogel material. Along with the details of the set-up, we illustrate the characteristics of the detectors during different time periods and the probable causes of the contamination. In particular we show that the replacement of the contaminated aerogel and parts of the reflecting material has almost restored the initial performance of the detectors.

S. Marrone; B. B. Wojtsekhowski; A. Acha; E. Cisbani; M. Coman; F. Cusanno; C. W. de Jager; R. De Leo; H. Gao; F. Garibaldi; D. W. Higinbotham; M. Iodice; J. J. LeRose; D. Macchia; P. Markowitz; E. Nappia; F. Palmisano; G. M. Urciuoli; I. van der Werf; H. Xiang; L. Y. Zhu

2008-10-25T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

Lessons Learned for the MICE Coupling Solenoid from the MICE Spectrometer Solenoids  

E-Print Network (OSTI)

liquid helium stream from the condenser from the helium gasstream going back to the condenser. AKNOWLEDGEMENT Thefrom the sleeve below the condenser to the bottom tank will

Green, Michael A.

2010-01-01T23:59:59.000Z

422

Progress on the Fabrication and Testing of the MICE Spectrometer Solenoids  

E-Print Network (OSTI)

on the vacuum vessel). to the condenser circuit issue. UponThe system consisted of condenser blocks attached to thecarried to and from the condenser through a direct, large

Virostek, Steve

2010-01-01T23:59:59.000Z

423

A picosecond time-resolved electron energy spectrometer based on Cerenkov radiation  

Science Conference Proceedings (OSTI)

The energy spectrum of relativistic electrons is an important characterization of high intensity laser-matter interactions. We present a technique that utilizes Cerenkov radiation to measure the time-resolved energy distribution of electrons. Electrons escaping from targets irradiated by high-intensity laser pulses were measured, demonstrating the feasibility of such a novel diagnostic. Limitations on the time resolution of this diagnostic are also discussed.

Elberson, Lee N.; Hill, Wendell T. III [Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States); Ping, Yuan; Shepherd, Ronnie L.; Patel, Pravesh K.; Mackinnon, Andrew J. [Lawrence Livermore National Laboratory, Livermore, California 94550-9234 (United States)

2009-02-15T23:59:59.000Z

424

TOWARDS BENCHMARK MEASUREMENTS FOR USED NUCLEAR FUEL ASSAY USING A LEAD SLOWING-DOWN SPECTROMETER  

E-Print Network (OSTI)

and the Karlsruhe Nuclear Research Center, Germany designed and operated a LSDS to assayed fresh mixed oxide (MOX

Danon, Yaron

425

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

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

Specifications of the PTAX Instrument Beam Spectrum: Thermal Monochromators Unpolarized PG(002) Polarized (commissioning) Analyzers Unpolarized PG(002), Be(101), Be(002), Si(111)...

426

Development of Superconducting High-Resolution Gamma-Ray Spectrometers for Nuclear Safeguards  

E-Print Network (OSTI)

a thermometer, and a weak thermal link. The absorber is ais then removed through a weak thermal link with a thermalconductance G across the weak thermal link as G = dP = nKT n

Dreyer, Jonathan

2012-01-01T23:59:59.000Z

427

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.

428

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

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

A good example is the study of famous "resonance" excitations in certain high temperature superconductors, thought to play a crucial role in electron pairing. In the unpolarized...

429

Use of Portable Gamma Spectrometers for Identifying Persons Exposed in a Nuclear Criticality Event  

Science Conference Proceedings (OSTI)

Detectors / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

K. G. Veinot; B. T. Gose; T. G. Davis; J. S. Bogard

430

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

431

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

432

Liquid Nitrogen-Cooled Fourier Transform Spectrometer System for Measuring Atmospheric Emission at High Altitudes  

Science Conference Proceedings (OSTI)

A cryogenically cooled FTS system capable of a spectral resolution of 0.06 cm?1 is described. The entire interferometer is operated at LN2 temperature with the exception of the Ge:Cu detector, which is cooled to below 10 K. In order to maintain ...

Frank H. Murcray; Frank J. Murcray; David G. Murcray; James Pritchard; George Vanasse; Hajime Sakai

1984-12-01T23:59:59.000Z

433

The Multiplexed Chemical Kinetic Photoionization Mass Spectrometer: A New Approach To Isomer-resolved Chemical Kinetics  

E-Print Network (OSTI)

Facility, Mail Stop 9055, Sandia National Laboratories,the U.S. Department of Energy. Sandia is a multiprogramlaboratory operated by Sandia Corporation, a Lockheed Martin

Osborne, David L.

2009-01-01T23:59:59.000Z

434

Geophysical parameter estimation with a passive microwave spectrometer at 54 / 118 / 183 / 425 GHz  

E-Print Network (OSTI)

(cont.) model of a convective cell is presented that provides a physical basis for this relationship.

Leslie, Robert Vincent, 1972-

2004-01-01T23:59:59.000Z

435

FABSOAR--A Fabry-Perot Spectrometer for Oxygen A-band Research Final Technical Report  

SciTech Connect

Because this was a Phase I project, it did not add extensively to the body of A-band knowledge. There was no basic research performed on that subject. The principal addition was that a mechanical and optical design for a triple-etalon Fabry-Perot interferometer (FABSOAR) capable of A-band sensing was sketched out and shown to be within readily feasible instrument fabrication parameters. The parameters for the proposed triple-etalon Fabry-Perot were shown to be very similar to existing Fabry-Perots built by Scientific Solutions. The mechanical design for the FABSOAR instrument incorporated the design of previous Scientific Solutions imagers, condensing the three three-inch-diameter etalons into a single, sturdy tube. The design allowed for the inclusion of a commercial off-the-shelf (COTS) filter wheel and a thermocooled CCD detector from Andor. The tube has supports to mount to a horizontal or vertical opticaltable surface, and was to be coupled to a Scientific Solutions pointing head at the Millstone Hill Observatory in Massachusetts for Phase II calibration and testing.

Watchorn, Steven

2010-09-10T23:59:59.000Z

436

The DOE Automated Radioxenon Sampler-Analyzer (ARSA) Beta-Gamma Coincidence Spectrometer Data Analyzer  

Science Conference Proceedings (OSTI)

The ARSA developed at PNNL for the CTBT measures four radioxenon isotopes. This paper will describe the software program along with data formats, various software controllable parameters and calculations.

Heimbigner, Tom R.; Bowyer, Ted W.; McIntyre, Justin I.; Abel, Keith H.; Hayes, James C.; Panisko, Mark E.; Pitts, W. K.

2000-09-01T23:59:59.000Z

437

Development of Superconducting High-Resolution Gamma-Ray Spectrometers for Nuclear Safeguards  

E-Print Network (OSTI)

of smuggling. Today, nuclear security is significantly morecritical importance of nuclear security, stating that thereJ. Doyle. Nuclear Safeguards, Security and Nonproliferation:

Dreyer, Jonathan

2012-01-01T23:59:59.000Z

438

Airborne gamma-ray spectrometer and magnetometer survey: Huron quadrangle, South Dakota. Final report  

SciTech Connect

Volume II contains the flight path, radiometric multi-parameter stacked profiles, magnetic and ancillary parameter stacked profiles, histograms, and anomaly maps for the Huron Quadrangle in South Dakota.

1981-04-01T23:59:59.000Z

439

Airborne gamma-ray spectrometer and magnetometer survey: Sioux Falls quadrangle, South Dakota. Final report  

SciTech Connect

Volume II contains the flight path, radiometric multi-parameter stacked profiles, magnetic and ancillary parameter stacked profiles, histograms, and anomaly maps for the Sioux Falls Quadrangle in South Dakota.

1981-05-01T23:59:59.000Z

440

An ultra-high throughput mutational spectrometer for human genetic diagnostics  

E-Print Network (OSTI)

Discovering the genetic causes of common diseases may require scanning for mutations in all of the genes in a million people, a significant undertaking. Such discoveries would revolutionize biotechnology, potentially ...

Forest, Craig Richard, 1978-

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

The Chopped Pyrgeometer: A New Step in Pyrgeometry  

Science Conference Proceedings (OSTI)

A new type of pyrgeometer, which uses modulation of the atmospheric radiation by a mechanical chopper, has been built for the use of ground-based and airborne measurement of broadband infrared atmospheric irradiances. The instrument basically ...

Dieter Lorenz; Peter Wendling; Peter Burkert; Friedrich Fergg; Günther Wildgruber

1996-02-01T23:59:59.000Z

442

by Roger Pynn Los Alamos National Laboratory LECTURE 2 ...  

Science Conference Proceedings (OSTI)

... SNS at ORNL will cost about $1.5B to construct & ~$140M per year to operate ... Cd is used in frame overlap choppers to absorb slower neutrons ...

2011-04-18T23:59:59.000Z

443

D. M. Mills* Introduction  

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

housing, (ii) the chopper or slit assembly, (iii) bearing assembly, and (iv) the drive motor. Typically the housing is evacuated to several Torr to reduce drag from the air. A...

444

Documentation for EQ-SANS | ORNL Neutron Sciences  

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

the usage of high-speed choppers in the future. Optical Components for the EQ-SANS Diffractometer Supplement documentation Manuals Data collection on EQ-SANS EQ-SANS Cheat Sheet...

445

Mechanical design of the SNS MEBT  

E-Print Network (OSTI)

et al. , “Progress with the SNS Front-End Systems,” PAC ’01,T. Saleh, “Design of the SNS MEBT,” Linac ‘00, Monterey,D.L. Schrage, “Progress with SNS Fast Beam Chopper,” PAC01,

Oshatz, D.; DeMello, A.; Doolittle, L.; Luft, P.; Staples, J.; Zachoszcz, A.

2001-01-01T23:59:59.000Z

446

Precision mass measurements of very short-lived, neutron-rich Na isotopes using a radiofrequency spectrometer  

E-Print Network (OSTI)

Mass measurements of high precision have been performed on sodium isotopes out to $^{30}$Na using a new technique of radiofrequency excitation of ion trajectories in a homogeneous magnetic field. This method, especially suited to very short-lived nuclides, has allowed us to significantly reduce the uncertainty in mass of the most exotic Na isotopes: a relative error of 5\\audi was achieved for $^{28}$Na having a half-life of only 30.5 ms and 9\\audi for the weakly produced $^{30}$Na. Verifying and minimizing binding energy uncertainties in this region of the nuclear chart is important for clarification of a long standing problem concerning the strength of the $N~=~20$ magic shell closure. These results are the fruit of the commissioning of the new experimental program Mistral.

Lunney, M D; Doubre, H; Henry, S; Monsanglant, C; De Saint-Simon, M; Thibault, C; Toader, C F; Borcea, C; Bollen, G

2001-01-01T23:59:59.000Z

447

Comparison of improved Aura Tropospheric Emission Spectrometer (TES) CO2 with HIPPO and SGP aircraft profile measurements  

E-Print Network (OSTI)

Propulsion Laboratory, California Institute of Technology, was performed under a contract with the National Aeronautics and Space

Kulawik, S.S.

2013-01-01T23:59:59.000Z

448

Use of HyMap imaging spectrometer data to map mineralogy in the Rodalquilar caldera, southeast Spain  

Science Conference Proceedings (OSTI)

The Rodalquilar epithermal gold alunite deposit occurs within the Rodalquilar caldera complex, in the Cabo de Gata volcanic field, a semi-arid region in southeast Spain. The epithermal mineralization is associated with an extensive east-west trending ...

E. Bedini; F. van der Meer; F. van Ruitenbeek

2009-01-01T23:59:59.000Z

449

An Open Path, Fast Response IR Spectrometer for Simultaneous Detection of C02 and Water Vapor Fluctuations  

Science Conference Proceedings (OSTI)

A fast response C02 and water vapor (H2O) analyzer was developed in this study for the measurement of atmospheric turbulence fluctuations and, in conjunction with a fast response anemometer, transport of these entities. High speed and high ...

M. J. Heikinheimo; G. W. Thurtell; G. E. Kidd

1989-08-01T23:59:59.000Z

450

Low-Level Measurement with a Noble Gas Mass Spectrometer for Organically Bound Tritium in Environmental Samples  

Science Conference Proceedings (OSTI)

Environmental and Organically Bound Tritium / Proceedings of the Ninth International Conference on Tritium Science and Technology (Part 2)

H. Kakiuchi et al.

451

Calibration transfer of intact olive NIR spectra between a pre-dispersive instrument and a portable spectrometer  

Science Conference Proceedings (OSTI)

The recent development of new portable devices enables the establishment of NIRS technology at industrial setting (on-line). However, the numerous existing NIRS databases based on a particular parameter, have been constructed with laboratory instruments ... Keywords: Calibration transfer, Intact olives, NIR spectroscopy, PDS, TOP

L. Salguero-Chaparro, B. Palagos, F. PeñA-RodríGuez, J. M. Roger

2013-08-01T23:59:59.000Z

452

3D position sensitive CdZnTe gamma-ray spectrometers improved performance with new ASICs  

E-Print Network (OSTI)

Energy Sciences and the NNSA ASC program. We thank E. Chandler and C. Mailhiot for their encouragement

He, Zhong

453

Inclusive meson production in 3.5 GeV pp collisions studied with the HADES spectrometer  

Science Conference Proceedings (OSTI)

We present the inclusive di?electron invariant?mass spectrum from p + p interactions at 3.5 GeV kinetic beam energy. It is a very important reference for the study of vector meson production off the nucleus

Anar Rustamov; The HADES Collaboration

2010-01-01T23:59:59.000Z

454

Scintillation detector development for the solenoidal tracker at RHIC (STAR) and the CEBAF large acceptance spectrometer (CLAS).  

E-Print Network (OSTI)

??After a brief introduction describing some of the physics and mechanics of scintillation detection, results of the development for the Central Trigger Barrel (CTB) for… (more)

Taylor, Simon John

1996-01-01T23:59:59.000Z

455

Manufacturing improvement and thermal property characterization of the frame structure of an Ultra-high Throughput Mutational Spectrometer  

E-Print Network (OSTI)

Constant denaturant capillary electrophoresis (CDCE) is a DNA separation technique that allows the detection of mutants at a fraction of 10Ì???. CDCE uses a region of constant temperature and constant denaturant concentration ...

Lin, Jiengju J. (Jiengju James)

2005-01-01T23:59:59.000Z

456

The Development and Use of the Berkeley Fluorescence Spectrometer to Characterize Microbial Content and Detect Volcanic Ash in Glacial Ice  

E-Print Network (OSTI)

V. M. Pashkevich, “Antarctic Ice Sheet as a model in Searchmethods for discovery of ice-entrapped microorganisms inV. M. Pashkevich, “Antarctic Ice Sheet as Object for Solving

Rohde, Robert Andrew

2010-01-01T23:59:59.000Z

457

Radial wave thermoacoustic engines: Theory and examples for refrigerators and high?gain narrow?bandwidth photoacoustic spectrometers  

Science Conference Proceedings (OSTI)

A theoretical analysis of radial wave thermoacoustic engines in cylindrical resonators is developed. Impedance and pressure translation equations are presented for open sections of the resonator and for heat exchangers. Coupled first?order differential equations are given for pressure and impedance in the temperature gradient supporting engine section (stack). These quantities are used to calculate heat and work flows and to predict engine performance. Theory and design of a variable quality factor resonator for enhanced photoacoustic spectroscopy are presented. The short stack approximation is developed for the radial geometry and is used along with plane?wave equations to compare refrigerator performance for these two geometries. Results of the comparison are that engines in the plane?wave geometry are better overall refrigerators when maximizing the coefficient of performance and cooling capacity together.

W. Patrick Arnott; Richard Raspet; Hans Moosmüller

1996-01-01T23:59:59.000Z

458

High energy resolution five-crystal spectrometer for high quality fluorescence and absorption measurements on an X-ray Absorption  

E-Print Network (OSTI)

at the Los Alamos Neutron Science Center (LANSCE). It will be unique among nuclear fuel irradiation at Idaho National Laboratory for fabrication of metallic nuclear fuels rods. A small bench scale caster and emission applications, and study their optical properties. Colloidal nanomaterials for light harvesting

459

Comparison of improved Aura Tropospheric Emission Spectrometer (TES) CO2 with HIPPO and SGP aircraft profile measurements  

E-Print Network (OSTI)

Aircraft observation of carbon dioxide at 8-13km altitudedecade, measurements of carbon dioxide (CO ) from space haveEmission Spectrome- ter (TES) carbon dioxide (CO ) satellite

Kulawik, S.S.

2013-01-01T23:59:59.000Z

460

EUV Spectra of the Full Solar Disk: Analysis and Results of the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS)  

E-Print Network (OSTI)

L. , Feldman, U. : 1972, The solar spectrum: Wavelengths andknowledge of the solar spectrum. SOHO/CDS/GIS has onedetails of the solar spectrum. Rocket ?ights typically

Sirk, M. M.; Hurwitz, M.; Marchant, W.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "angular-range chopper 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

Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers  

DOE Patents (OSTI)

A high speed, digitally based, signal processing system is disclosed which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system`s principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom. 14 figs.

Warburton, W.K.

1998-06-30T23:59:59.000Z

462

Method and apparatus for digitally based high speed x-ray spectrometer for direct coupled use with continuous discharge preamplifiers  

DOE Patents (OSTI)

A high speed, digitally based, signal processing system which accepts directly coupled input data from a detector with a continuous discharge type preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system's principal elements are an analog signal conditioning section, a combinatorial logic section which implements digital triangular filtering and pileup inspection, and a microprocessor which accepts values captured by the logic section and uses them to compute x-ray energy values. Operating without pole-zero correction, the system achieves high resolution by capturing, in conjunction with each peak value from the digital filter, an associated value of the unfiltered signal, and using this latter signal to correct the former for errors which arise from its local slope terms. This correction greatly reduces both energy resolution degradation and peak centroid shifting in the output spectrum as a function of input count rate. When the noise of this correction is excessive, a modification allows two filtered averages of the signal to be captured and a corrected peak amplitude computed therefrom.

Warburton, William K. (1300 Mills St., Menlo Park, CA 94025)

1998-01-01T23:59:59.000Z

463

A New Low-Energy Neutron Spectrometer Based on Position-Sensitive Proportional Counter for Accelerator-Based Neutron Source  

Science Conference Proceedings (OSTI)

Neutron Measurements / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Measurements and Instrumentation

I. Murata; H. Miyamaru; I. Kato; S. Yoshida; Y. Mori

464

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

465

Note: A portable, light-emitting diode-based ruby fluorescence spectrometer for high-pressure calibration  

SciTech Connect

Ruby (Al{sub 2}O{sub 3}, with {approx}0.5 wt. % Cr doping) is one of the most widely used manometers at the giga-Pascal scale. Traditionally, its fluorescence is excited with intense laser sources. Here, I present a simple, robust, and portable design that employs light-emitting diodes (LEDs) instead. This LED-based system is safer in comparison with laser-based ones.

Feng Yejun [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2011-04-15T23:59:59.000Z

466

Investigating ion-surface collisions with a niobium superconducting tunnel junction detector in a time-of-flight mass spectrometer  

E-Print Network (OSTI)

Physics at the University of Manitoba for some helpful andPhysics at the University of Manitoba for some helpful and

Westmacott, G.

2011-01-01T23:59:59.000Z

467

A Systems Level Characterization and Tradespace Evaluation of a Simulated Airborne Fourier Transform Infrared Spectrometer for Gas Detection  

E-Print Network (OSTI)

of operation; and (d) flexibility to fuel changes. In a dry sorbent injection system, trona or sodium In a dry sorbent injection system, trona (Na2CO3·NaHCO3· 2H2O) or sodium bicarbonate (NaHCO3) is injected electrostatic precipitators or fabric filters. Figure 1: Raw Trona under Microscope The chemical reactions

Salvaggio, Carl