These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

MPS (Multiparticle Spectrometer) data acquisition software system  

SciTech Connect

A description of the software for a FASTBUS based data acquisition system in use at the Brookhaven National Laboratory Multiparticle Spectrometer is presented. Data reading and formatting is done by the SLAC Scanner Processors (SSP's) resident in the FASTBUS system. A multiprocess software system on VAX computers is used to communicate with the SSP's, record the data, and monitor on-line the progress of high energy and heavy ion experiments. The structure and the performance of this system are discussed. 4 refs., 1 fig.

Saulys, A.C.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Longacre, R.S.; Love, W.A.; Morris, T.W.; Platner, E.D.; Lindenbaum, S.J.; Chan, C.S.

1989-04-04

2

Light Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory  

SciTech Connect

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

2011-12-01

3

A Spatial Heterodyne Spectrometer for VUV Laboratory Astrophysics  

NASA Astrophysics Data System (ADS)

All reflection Spatial Heterodyne Spectrometer (SHS) designs have the potential to revolutionize spectroscopy in the VUV. The advantages of interferometric spectrometers such as the Kitt Peak 1m Fourier Transform Spectrometer (FTS) in the near UV, visible, and IR for laboratory measurements of spectroscopic data including emission branching fractions, improved level energies, and hyperfine/isotopic parameters are well documented. These advantages include: (1) very high spectral resolving powers, (2) excellent absolute wavenumber accuracy, (3) extremely broad spectral coverage, (4) high data collection rates, and (5) insensitivity to source drift during branching fraction measurements. Some progress has been made in extending spectroscopic interferometry into the VUV using modified versions of Chelsea Instruments FTS, but beam splitter performance issues and the problem of generally low sensitivity at wavenumbers above 67,000 cm-1 have proven to be quite stubborn. We are starting the construction of a SHS which has promise of extending spectroscopic interferometry to the window limit ( 90,000 cm-1) and eventually above the window limit. In addition to the lack of transmitting optics, the SHS has other advantages. Optical imperfections are much more serious in a traditional Michelson FTS than in a SHS. The localized fringes of equal thickness in a SHS deviate from straight lines due to optical imperfections, but such deviations can be corrected with software after transferring the interferogram from the CCD. Similar optical imperfections from either figure or index of refraction variations in a Michelson FTS lower fringe contrast and degrade the instrument sensitivity. The use of a CCD detector array to record the spatially distributed interferogram means that the SHS is quite compatible with transient, low duty cycle sources which are common in the VUV. Supported by NASA.

Lawler, J. E.; Roesler, F. L.; Harlander, J.

2005-05-01

4

Holographic spectrometer for astronomy: design and experiments--initial laboratory results  

NASA Astrophysics Data System (ADS)

In order to fulfill the need of high astronomical observation spectral resolution, we are developing a new stationary interferometric spectrometer: heterodyne holographic spectrometer (HHS). It utilizes the configuration of a Twyman- Green interferometer with two arms adjusted for zero path difference and with a plane diffraction grating replacing one of the arm mirrors. So, it combines the multi-advantages of traditional spectrometers: SGS and FTS (slit grating spectrometer and Fourier transform spectrometer), and avoids their disadvantages, especially in the observation with telescope. We get its experimental result in the laboratory and have a simple discussion on its application prospect in astronomy.

Zhou, Bifang; Wang, Haitao; Zhao, Peiqian

1997-05-01

5

Portable Remote Imaging Spectrometer (PRISM): Laboratory and Field Calibration  

NASA Technical Reports Server (NTRS)

We report the characteristics of the Portable Remote Imaging Spectrometer, an airborne sensor specifically designed for the challenges of coastal ocean research. PRISM has high signal to noise ratio and uniformity, as well as low polarization sensitivity. Acquisition of high quality data has been demonstrated with the first engineering flight.

Mouroulis, Pantazis; Van Gorp, Byron; Green, Robert O.; Eastwood, Michael; Boardman, Joseph; Richardson, Brandon S.; Rodriguez, Jose I.; Urquiza, Eugenio; Franklin, Brian D.; Gao, Bo-Cai

2012-01-01

6

Laboratory radiometric calibration for the convex grating imaging spectrometer  

NASA Astrophysics Data System (ADS)

The radiometric calibration of imaging spectrometer plays an import role for scientific application of spectral data. The radiometric calibration accuracy is influenced by many factors, such as the stability and uniformity of light source, the transfer precision of radiation standard and so on. But the deviation from the linear response mode and the polarization effect of the imaging spectrometer are always neglected. In this paper, the linear radiometric calibration model is constructed and the radiometric linear response capacity is test by adjusting electric gain, exposure time and radiance level. The linear polarizer and the sine function fitting algorithm are utilized to measure polarization effect. The integrating sphere calibration system is constructed in our Lab and its spectral radiance is calibrated by a well-characterized and extremely stable NIST traceable transfer spectroradiometer. Our manufactured convex grating imaging spectrometer is relative and absolute calibrated based on the integrating sphere calibration system. The relative radiometric calibration data is used to remove or reduce the radiometric response non-uniformity every pixel of imaging spectrometer while the absolute radiometric calibration is used to construct the relationship between the physical radiant of the scene and the digital number of the image. The calibration coefficients are acquired at ten radiance levels. The diffraction noise in the images can be corrected by the calibration coefficients and the uniform radiance image can be got. The calibration result shows that our manufactured imaging spectrometer with convex grating has 3.0% degree of polarization and the uncertainties of the relative and absolute radiometric calibrations are 2.4% and 5.6% respectively.

Zhou, Jiankang; Chen, Xinhua; Chen, Yuheng; Ji, Yiqun; Shen, Weimin

2014-09-01

7

Multiparticle entanglement purification protocols  

NASA Astrophysics Data System (ADS)

Purification schemes for multiparticle entangled states cannot be treated as straightforward extensions of those two-particle ones because of the lack of symmetry they possess. We propose purification protocols for a wide range of mixed entangled states of many particles. These are useful for understanding entanglement, and could be of practical significance in multiuser cryptographic schemes or distributed quantum computation and communication. We show that operating locally on multiparticle entangled states directly is more efficient than relying on two-particle purification.

Murao, M.; Plenio, M. B.; Popescu, S.; Vedral, V.; Knight, P. L.

1998-06-01

8

Electron Positron Proton Spectrometer for use at Laboratory for Laser Energetics  

SciTech Connect

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

2010-04-07

9

GIOVE, a shallow laboratory Ge-spectrometer with 100 ?Bq/kg sensitivity  

NASA Astrophysics Data System (ADS)

A new germanium gamma spectrometer called GIOVE (Germanium spectrometer with Inner and Outer Veto) has been set up at the underground/shallow laboratory (15 m w.e.) of MPI-K. Its double plastic scintillator veto system and neutron moderation interlayer lower the background by more than one order of magnitude compared to the other existing spectrometer at this facility. The integral (40-2700 keV) background rate of about 290 counts (day kg)-1 is just a factor 4 to 8 above that of the GeMPI spectrometers operated at LNGS (3800 m w.e.) and thus proves that even under shallow overburden sub mBq/kg sensitivities are achievable. Extended material screening and neutron attenuation studies preceded the final design of the spectrometer. The technical realization of the spectrometer is described in detail with special emphasis on the inner veto system. For its optimisation a simulation model was developed for light collection on small low activity PMT's under various geometrical conditions. Radon suppression is accomplished by employing a gas tight sample container and a nitrogen flushed glove-box system with an airlock. The active volume of the crystal was modelled by absorption scanning measurements and Monte Carlo simulations. The complete shield is implemented in a Geant4 based simulation framework.

Heusser, G.; Weber, M.; Denz, T.; Hakenmueller, J.; Hofacker, R.; Lackner, R.; Lindner, M.; Maneschg, W.; Reisfelder, M.; Simgen, H.; Schreiner, J.; Stolzenburg, D.; Strecker, H.; Westermann, J.

2013-08-01

10

Ultra-Compact Imaging Spectrometer (UCIS) for In-Situ Planetary Mineralogy: Laboratory and Field Calibration  

NASA Technical Reports Server (NTRS)

The Ultra-Compact Imaging Spectrometer (UCIS) is a miniature telescope and spectrometer system intended for mapping terrain mineralogy over distances from 1.5 m to infinity with spatial sampling of 1.35 mrad over a 33 deg field, and spectral sampling of 10 nm in the 600-2500 nm range. The core of the system has been designed for operation in a Martian environment, but can also be used in a terrestrial environment when placed inside a vacuum vessel. We report the laboratory and field calibration data that include spatial and spectral calibration, and demonstrate the use of the system.

Van Gorp, Byron; Mouroulis, Pantazis; Green, Robert O.; Rodriguez, Jose I.; Blaney, Diana; Wilson, Daniel W.; Sellar, R. Glenn; Richardson, Brandon S.

2012-01-01

11

Laboratory Astrophysics, QED, and other Measurements using the EBIT Calorimeter Spectrometer at LLNL  

SciTech Connect

We have used the EBIT Calorimeter Spectrometer (ECS), a microcalorimeter instrument built by the calorimeter group at the NASA/Goddard Space Flight Center, to make a variety of measurements since its installation at Lawrence Livermore National Laboratory's EBIT facility. These include measurements of charge exchange between neutral gas and K- and L-shell ions, measurements of the X-ray transmission efficiency of optical blocking filters, high resolution measurements of transition energies for high-Z, highly charged ions, and measurements of M and L-shell emission from highly charged tungsten following on earlier measurements of L-shell gold. Our results will see application in the interpretation of the spectra from the Jovian atmosphere and of the diffuse soft X-ray background, in tests of QED, and in diagnosing inertial and magnetic confinement fusion plasmas. These measurements augment previous laboratory astrophysics, atomic physics, and calibration measurements made using earlier versions of NASA's microcalorimeter spectrometer.

Brown, G V; Adams, J S; Beiersdorfer, P; Clementson, J; Frankel, M; Kahn, S M; Kelley, R L; Kilbourne, C A; Koutroumpa, D; Leutenegger, M; Porter, F S; Thorn, D B; Trabert, E

2009-08-25

12

Laboratory calibration of the Extreme-Ultraviolet Imaging Spectrometer for the Solar-B satellite  

Microsoft Academic Search

The laboratory end-to-end testing of the Extreme-Ultraviolet Imaging Spectrometer (EIS) for the Solar-B satellite is reported. A short overview of the EIS, which observes in two bands in the extreme-ultraviolet wavelength range, is given. The calibration apparatus is described, including details of the light sources used. The data reduction and analysis procedure are outlined. The wavelength calibration using a Penning

James Lang; Barry J. Kent; Wolfgang Paustian; Charles M. Brown; Christian Keyser; Mark R. Anderson; Giles C. R. Case; Rahil A. Chaudry; Adrian M. James; Clarence M. Korendyke; C. David Pike; Brian J. Probyn; David J. Rippington; John F. Seely; Jason A. Tandy; Matthew C. R. Whillock

2006-01-01

13

A novel von Hamos spectrometer for efficient X-ray emission spectroscopy in the laboratory  

SciTech Connect

We present a novel, highly efficient von Hamos spectrometer for X-ray emission spectroscopy (XES) in the laboratory using highly annealed pyrolitic graphite crystals as the dispersive element. The spectrometer covers an energy range from 2.5 keV to 15 keV giving access to chemical speciation and information about the electronic configuration of 3d transition metals by means of the K? multiplet. XES spectra of Ti compounds are presented to demonstrate the speciation capabilities of the instrument. A spectral resolving power of E/?E = 2000 at 8 keV was achieved. Typical acquisition times range from 10?min for bulk material to hours for thin samples below 1??m.

Anklamm, Lars, E-mail: anklamm@physik.tu-berlin.de; Schlesiger, Christopher; Malzer, Wolfgang; Grötzsch, Daniel; Neitzel, Michael; Kanngießer, Birgit [Institute for Optic and Atomic Physics, Technical University Berlin, Hardenbergstr. 36, 10623 Berlin (Germany)

2014-05-15

14

Laboratory performances of the solar multichannel resonant scattering spectrometer prototype of the GOLF-New Generation instrument  

E-print Network

This article quickly summarizes the performances and results of the GOLF/SoHO resonant spectrometer, thus justifying to go a step further. We then recall the characteristics of the multichannel resonant GOLF-NG spectrometer and present the first successful performances of the laboratory tests on the prototype and also the limitations of this first technological instrument. Scientific questions and an observation strategy are discussed.

S. Turck-Chieze; P. H. Carton; S. Mathur; J. -C. Barriere; P. Daniel-Thomas; C. Lahonde-Hamdoun; R. Granelli; D. Loiseau; F. Nunio; Y. Piret; J. M. Robillot

2008-06-21

15

Comparison of spectral data gathered from a laboratory spectrometer and TM images with and without shadow correction  

SciTech Connect

Spectral reflectance data from field samples were determined with a laboratory spectrometer (Beckman DK-2A). The spectral curves obtained with the spectrometer were correlated with the histograms determined from the images. The tightly defined histograms from the shadow corrected TM provided the best correlation with the rock data. Several units, including the Rainier Mesa Member of the Timber Mountain Tuff, showed multiple spectral patterns on both images and rock spectra. This difference was evaluated versus geochemistry, hematitic alteration, devitrification, pumice content, and degree of welding. 11 refs., 3 figs., 3 tabs.

Thiessen, R.L.; Eliason, J.R.

1989-01-01

16

The characteristics of a low background germanium gamma ray spectrometer at China JinPing Underground Laboratory.  

PubMed

A low background germanium gamma ray spectrometer, GeTHU, has been installed at China JinPing Underground Laboratory (CJPL). The integral background count rate of the spectrometer was 0.629 cpm between 40 and 2700 keV, the origins of which were studied by Monte Carlo simulation. Detection limits and efficiencies were calculated for selected gamma peaks. Some samples of rare event experiments were measured and (137)Cs contamination was found in boric acid. GeTHU will be mainly used to measure environmental samples and screen materials in dark matter and double beta decay experiments. PMID:24950199

Zeng, Zhi; Mi, Yuhao; Ma, Hao; Cheng, Jianping; Su, Jian; Yue, Qian

2014-09-01

17

Calibration of the Mars Science Laboratory Alpha Particle X-ray Spectrometer  

NASA Astrophysics Data System (ADS)

The alpha-particle X-ray spectrometer (APXS) for the Mars Science Laboratory (MSL) mission was calibrated for routine analysis of: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Zn, Br, Rb, Sr, and Y. The following elements were also calibrated, but may be too low to be measured (10s-100s ppm) for their usual abundance on Mars: V, Cu, Ga, As, Se and W. An extensive suite of geological reference materials, supplemented by pure chemical elements and compounds was used. Special attention was paid to include phyllosilicates, sulfates and a broad selection of basalts as these are predicted minerals and rocks at the Gale Crater landing site. The calibration approach is from first principles, using fundamental physics parameters and an assumed homogeneous sample matrix to calculate expected elemental signals for a given instrument setup and sample composition. Resulting concentrations for most elements accord with expected values. Deviations in elements of lower atomic number (Na, Mg, Al) indicate significant influences of mineral phases, especially in basalts, ultramafic rocks and trachytes. The systematics of these deviations help us to derive empirical, iterative corrections for different rock groups, based on a preliminary APXS analysis which assumes a homogeneous sample. These corrections have the potential to significantly improve the accuracy of APXS analyses, especially when other MSL instrument results, such as the X-ray diffraction data from CheMin, are included in the overall analysis process.

Campbell, John L.; Perrett, Glynis M.; Gellert, Ralf; Andrushenko, Stefan M.; Boyd, Nicholas I.; Maxwell, John A.; King, Penelope L.; Schofield, Céleste D. M.

2012-09-01

18

Calibration of the Mars Science Laboratory Alpha Particle X-Ray Spectrometer  

NASA Astrophysics Data System (ADS)

We have used a suite of over 60 geochemical reference standards for the calibration of the Mars Science Laboratory (MSL) Alpha Particle X-ray Spectrometer (APXS). For the elements P, S, Cl and Br we have supplemented this suite by adding various amounts of relevant chemical compounds to a powdered basalt standard. Special attention has been paid to include phyllosilicates, sulphates and a broad selection of igneous basalts as these are predicted key deposits at the MSL landing site, Gale Crater. The calibration is performed from first principles using x-ray excitation cross sections for the alpha particle and x-ray radiation source and an assumed homogeneous sample matrix. Remaining deviations indicate significant influences of mineral phases especially for light elements in basalts, ultra-mafic rocks and trachytes. Supporting x-ray diffraction work has helped to derive empirical, iterative corrections for distinct rock types, based on the first APXS analysis, assuming a homogeneous sample. These corrections have the potential to significantly improve the accuracy of APXS analyses, especially when other MSL instrument results, such as x-ray diffraction data from ChemMin, are included in the overall analysis process.

Perrett, G. M.; Campbell, J. L.; Gellert, R.; King, P. L.; Maxwell, J. A.; Andrushenko, S. M.

2011-12-01

19

Laboratory Astrophysics using a Microcalorimeter and Bragg Crystal Spectrometer on an Electron Beam Ion Trap  

NASA Technical Reports Server (NTRS)

During the past year we have been preparing our new microcalorimeter system for permanent delivery to the NIST EBIT. Unfortunately, there have been delays due to technical difficulties in the fabrication of the two-stage adiabatic demagnetization refrigerator and in the life expectancy of the thin windows used for internal thermal baffling of the infrared radiation. These problems have been solved and we are completing tests of the entire system and it will be set up at NIST during the first week of May. Several photos of the new system are shown in Figures 1A and 1B. This microcalorimeter spectrometer only requires helium refills every three days (as opposed to every 24 hours) and it will hold a temperature! of 65 mK for up to 48 hours (as opposed to 8 hours). Consequently, the efficiency of data acquisition will improve dramatically. In parallel we have published a paper that reviews our previous work (Takacs et al. 2003), especially on Fe XVII, in the context of recent measurements by other groups. This paper is included. We highlight a recent measurement of a broad band spectrum of Fe in Figure 2 that simultaneously includes L and K radiation. It is compared with the simulated spectrum of the Perseus Cluster that one could expect to obtain with a microcalorimeter in the focus of a grazing incidence telescope such as the one being designed for Constellation X. Both the charge state distributions and the relative intensity ratios of the emission lines within the particular charge state are very similar in the two spectra. This further demonstrates the importance and relevance of the laboratory measurements in predicting the components of cosmic spectra.

Brinton, John C. (Technical Monitor); Silver, Eric

2004-01-01

20

Laboratory and field measurements of organic aerosols with the photoionization aerosol mass spectrometer  

NASA Astrophysics Data System (ADS)

Analytical methods developed to sample and characterize ambient organic aerosols often face the trade-off between long sampling times and the loss of detailed information regarding specific chemical species present. The soft, universal ionization scheme of the Photoionization Aerosol Mass Spectrometer (PIAMS) allows for identification of various chemical compounds by a signature ion, often the molecular ion. The goal of this thesis work is to apply PIAMS to both laboratory and field experiments to answer questions regarding the formation, composition, and behavior of organic aerosols. To achieve this goal, a variety of hardware and software upgrades were administered to PIAMS to optimize the instrument. Data collection and processing software were either refined or built from the ground up to simplify difficult or monotonous tasks. Additional components were added to PIAMS with the intent to automate the instrument, enhance the results, and make the instrument more rugged and user-friendly. These changes, combined with the application of an external particle concentration system (mini-Versatile Aerosol Concentration Enrichment System, m-VACES), allowed PIAMS to be suitable for field measurements of organic aerosols. Two such field campaigns were completed, both at the State of Delaware Air Quality Monitoring Site in Wilmington, Delaware: a one week period in June, 2006, and an 18 day period in October and November of 2007. A sampling method developed was capable of collecting sufficient ambient organic aerosol and analyzing it with a time resolution of 3.5 minutes. Because of this method, short term concentration changes of individual species can be tracked. Combined with meteorological data, the behavior of these species can be analyzed as a function of time or wind direction. Many compounds are found at enhanced levels during the evening/night-time hours; potentially due to the combined effects of temperature inversion, and fresh emissions in a cooler environment. The high-time resolution data shows that rapid concentration changes of a common individual species can be lost with traditional bulk sampling, and a time resolution of 30 minutes is suggested to accurately represent these changes. Using the mass spectra collected from the extended sampling campaign, source apportionment was performed with positive matrix factorization (PMF). The resulting model features six factors either correlated to specific sources (meat cooking, car emissions/road dust, diesel exhaust) or types of compounds (phthalates, alkanes/alkanoic acids, PAHs). The high-time resolution data allowed for the observation of specific trends in each factor's behavior as a function of time and wind direction relative to the receptor site. Elemental carbon/organic carbon (EC/OC) data is used to calculate the percentages of primary and secondary organic aerosol. Primary organic aerosol (POA) constituted the vast majority of the total carbon at 91% (an average of 2.8 +/- 1.1mug/m 3); 30% of which came from combustion, and 70% from non-combustion sources. These results can be explained by the PIAMS data: the diesel factor contributes to the combustion-related POA; the car/road dust, meat cooking, and alkane/alkanoic acid factors contribute the majority of non-combustion POA. The remaining factors represent <5% of the remaining OC. Considering the compatibility of data from the EC/OC and PIAMS, the ability of PIAMS to yield molecular species information to further define the primary and secondary organic aerosol factions is a distinct advantage in describing the behavior of the Wilmington organic aerosol. PIAMS was also applied to laboratory experiments. These experiments simulated complex environmental processes in order to focus on answering a central question. By mixing cholesterol aerosol with ozone in a smog chamber, and monitoring the concentration of cholesterol with PIAMS, the rate of reaction was determined. This rate indicates that cholesterol aerosol, which is a suggested source tracer, will remain in the ambient air for a few days under norma

Dreyfus, Matthew A.

21

Using an NMR Spectrometer to Do Magnetic Resonance Imaging: An Undergraduate Physical Chemistry Laboratory Experiment  

ERIC Educational Resources Information Center

A conventional Fourier-transform NMR spectrometer with a triple-axis gradient probe can function as a MRI imager. In this experiment students gain hands-on experience with MRI while they learn about important principles underlying the practice of NMR, such as gradients, multi-dimensional spectroscopy, and relaxation. Students image a biological…

Steinmetz, Wayne E.; Maher, M. Cyrus

2007-01-01

22

Laboratory and field measurements of organic aerosols with the photoionization aerosol mass spectrometer  

Microsoft Academic Search

Analytical methods developed to sample and characterize ambient organic aerosols often face the trade-off between long sampling times and the loss of detailed information regarding specific chemical species present. The soft, universal ionization scheme of the Photoionization Aerosol Mass Spectrometer (PIAMS) allows for identification of various chemical compounds by a signature ion, often the molecular ion. The goal of this

Matthew A. Dreyfus

2008-01-01

23

Laboratory Tests of a Handheld X-Ray Fluorescence Spectrometer: A Tool for Planetary Exploration  

NASA Astrophysics Data System (ADS)

Maximizing the science return from a mission to another planetary surface involves the integration of science objectives with deployable technologies that enable the collection of data and samples. For long duration manned missions, it is likely that more samples will be collected than can be returned to Earth due to mass limits. A niche exists for technologies that help prioritize samples for return, provide data for future sample handling and curation, and characterization for samples that are not returned to Earth. To fill this niche, hardware and protocols for field instruments are currently being developed and evaluated at NASA Johnson Space Center and Arizona State University. Our goal is to develop an easily used, environmentally isolated facility as part of the astronaut surface habitat for preliminary sample characterization and down-selection. NASA has constructed a prototype, GeoLab, as a testbed for evaluating the scientific applicability and operational considerations of various analytical instruments. One instrument under evaluation is a small, portable x-ray fluorescence (XRF) spectrometer that can be also be used by astronaut explorers as part of their field gear while on scientific sorties, or on robotic field assistants. We report on preliminary usability tests for commercially available handheld XRF instruments. These instruments collect data by contacting the surface of a rock or sediment sample with an 8 mm-wide sensor window. Within 60 seconds, the devices can provide relatively precise data on the abundance of major and trace elements heavier than Na. Lab-based handheld XRF analyses of terrestrial and lunar samples, compared with those made with full-scale laboratory XRF systems, show good correlation, but we continue to investigate potential sources of error and the need for careful calibration with standards of known composition. Specifically, we use a suite of five terrestrial and five lunar basalts, all well characterized by conventional XRF technology, to evaluate the handheld technology. All of these samples are fine-grained and homogeneous, and were selected to eliminate effects introduced to the data by inconsistencies in the sample matrix, or added complexities like increased vesicularity or phenocryst content. Our calibration curves are built from smooth, sawed surfaces. We have examined all major elements, minus Na (which falls below the instrument sensitivity). Initial tests show that reproducible and reliable calibration curves are produced for Ca, Fe, Al, Ti, and Si, but the curves produced for Mg, Mn, K and P include greater uncertainties. We are currently investigating how the instrument signal variably drops off as a function of surface roughness and distance to the instrument window. Through studies such as these in the simulated GeoLab setting, we can better understand the instrument's capabilities in a field environment, both on Earth and for potential future missions to other planetary surfaces.

Young, K. E.; Evans, C. A.; Hodges, K.

2011-12-01

24

Multiple detector focal plane array ultraviolet spectrometer for the AMPS laboratory  

NASA Technical Reports Server (NTRS)

The possibility of meeting the requirements of the amps spectroscopic instrumentation by using a multi-element focal plane detector array in a conventional spectrograph mount was examined. The requirements of the detector array were determined from the optical design of the spectrometer which in turn depends on the desired level of resolution and sensitivity required. The choice of available detectors and their associated electronics and controls was surveyed, bearing in mind that the data collection rate from this system is so great that on-board processing and reduction of data are absolutely essential. Finally, parallel developments in instrumentation for imaging in astronomy were examined, both in the ultraviolet (for the Large Space Telescope as well as other rocket and satellite programs) and in the visible, to determine what progress in that area can have direct bearing on atmospheric spectroscopy.

Feldman, P. D.

1975-01-01

25

LABORATORY EVALUATION OF TUNABLE ATOMIC LINE MOLECULAR SPECTROMETERS FOR BENZENE ANALYSIS  

EPA Science Inventory

Tunable Atomic Line Molecular Spectroscopy (TALMS) is a high resolution, differential absorption technique used in the ultraviolet region. Under Interagency Agreements EPA-80-D-X1014 and AD-89-F-2A008 with Lawrence Berkeley Laboratory, two prototype TALMS instruments were designe...

26

Negative chemiions formed in jet fuel combustion: new insights from jet engine and laboratory measurements using a quadrupole ion trap mass spectrometer apparatus  

Microsoft Academic Search

Measurements were made of mass numbers and composition of negative chemiions produced in jet fuel combustion in the exhaust of a jet engine and of a burner in the laboratory. The measurements made by a novel quadrupole ion trap mass spectrometer apparatus revealed the presence of three major ion families: ions containing an HSO4? “core” or an NO3? “core”, and

A Kiendler; St Aberle; F Arnold

2000-01-01

27

Laboratory Astrophysics using a Microcalorimeter and Bragg Crystal Spectrometer on an Electron Beam Ion Trap  

NASA Technical Reports Server (NTRS)

When we last reported, our new microcalorimeter system was being prepared for delivery and permanent installation at the NIST EBIT. This occurred in June 2003 and check-out with the internal calibration source and EBIT plasma x-rays took place over the next several months during which time we modified several component parts to improve the performance. These changes included: 1) A redesign of the x-ray calibration source from a direct electron impact source to one that irradiates the microcalorimeter with fluorescent x-rays. The resulting calibration lines are free of bremsstrahlung background; 2) The microcalorimeter electronic circuit has been significantly improved to ensure long-term stability for the lengthy upcoming runs of the EBIT. Both the preamplifier feedback resistors were changed and the first stage of the preamplifier redesigned. Several photos of the new system are shown in slides 3 and 4. This microcalorimeter spectrometer only requires helium refills every three days (as opposed to every 24 hours in our earlier system) and it will hold a temperature of 65 mK for up to 48 hours (as opposed to 8 hours). Consequently, the efficiency of data acquisition will improve dramatically. The first x-ray spectra of the new calibration source made with the 4-element detector array is shown. An example of the temperature control capabilities of the ADR for a 23 hour interval is shown. The horizontal line shows the temperature stability (about +/- 3 micro kelvin). There are a few short-lived heating excursions caused by technical staff working on the EBIT machine simultaneously. During actual experimental runs these are absent. This temporal profile was interrupted to test additional components of the system; otherwise, the temperature controlling would have continued for another 24 hours.

Silver, Eric

2004-01-01

28

Multiparticle clusters and carbon superstructure in martensite  

Microsoft Academic Search

On the basis of experimentally verified concentration expansion tensor values, stress induced two-particle C-C potentials have been calculated in harmonic approximation. A calculation method has been developed and expressions derived for the evaluation of multiparticle interaction potentials and cluster population. The temperature range of the applicability of the method has been estimated. On the basis of this method it has

L. Dabrowski; Otwock-Swierk Poland

1995-01-01

29

Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). A description of the sensor, ground data processing facility, laboratory calibration, and first results  

NASA Technical Reports Server (NTRS)

The papers in this document were presented at the Imaging Spectroscopy 2 Conference of the 31st International Symposium on Optical and Optoelectronic Applied Science and Engineering, in San Diego, California, on 20 and 21 August 1987. They describe the design and performance of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) sensor and its subsystems, the ground data processing facility, laboratory calibration, and first results.

Vane, Gregg (editor)

1987-01-01

30

Micromachined mass spectrometer  

Microsoft Academic Search

The general purpose of the present study is the realisation with silicon microtechnologies of a low cost miniature mass spectrometer working at high pressure (>1Pa). For this, two kinds of filter have been developed in our laboratory: a quadrupole mass spectrometer and a Wien filter, which is presented in this paper. The micromachined device contains on one single chip the

Nicolas Sillon; Robert Baptist

2002-01-01

31

Laboratory-based micro-X-ray fluorescence setup using a von Hamos crystal spectrometer and a focused beam X-ray tube  

SciTech Connect

The high-resolution von Hamos bent crystal spectrometer of the University of Fribourg was upgraded with a focused X-ray beam source with the aim of performing micro-sized X-ray fluorescence (XRF) measurements in the laboratory. The focused X-ray beam source integrates a collimating optics mounted on a low-power micro-spot X-ray tube and a focusing polycapillary half-lens placed in front of the sample. The performances of the setup were probed in terms of spatial and energy resolution. In particular, the fluorescence intensity and energy resolution of the von Hamos spectrometer equipped with the novel micro-focused X-ray source and a standard high-power water-cooled X-ray tube were compared. The XRF analysis capability of the new setup was assessed by measuring the dopant distribution within the core of Er-doped SiO{sub 2} optical fibers.

Kayser, Y., E-mail: yves.kayser@psi.ch [Department of Physics, University of Fribourg, 1700 Fribourg (Switzerland); Paul Scherrer Institut, 5232 Villigen-PSI (Switzerland); B?achucki, W.; Dousse, J.-Cl.; Hoszowska, J. [Department of Physics, University of Fribourg, 1700 Fribourg (Switzerland)] [Department of Physics, University of Fribourg, 1700 Fribourg (Switzerland); Neff, M.; Romano, V. [Institute of Applied Physics, University of Bern, 3012 Bern (Switzerland)] [Institute of Applied Physics, University of Bern, 3012 Bern (Switzerland)

2014-04-15

32

Analytical techniques for retrieval of atmospheric composition with the quadrupole mass spectrometer of the Sample Analysis at Mars instrument suite on Mars Science Laboratory  

NASA Astrophysics Data System (ADS)

The Sample Analysis at Mars (SAM) instrument suite is the largest scientific payload on the Mars Science Laboratory (MSL) Curiosity rover, which landed in Mars' Gale Crater in August 2012. As a miniature geochemical laboratory, SAM is well-equipped to address multiple aspects of MSL's primary science goal, characterizing the potential past or present habitability of Gale Crater. Atmospheric measurements support this goal through compositional investigations relevant to martian climate evolution. SAM instruments include a quadrupole mass spectrometer, a tunable laser spectrometer, and a gas chromatograph that are used to analyze martian atmospheric gases as well as volatiles released by pyrolysis of solid surface materials (Mahaffy et al., 2012). This report presents analytical methods for retrieving the chemical and isotopic composition of Mars' atmosphere from measurements obtained with SAM's quadrupole mass spectrometer. It provides empirical calibration constants for computing volume mixing ratios of the most abundant atmospheric species and analytical functions to correct for instrument artifacts and to characterize measurement uncertainties. Finally, we discuss differences in volume mixing ratios of the martian atmosphere as determined by SAM (Mahaffy et al., 2013) and Viking (Owen et al., 1977; Oyama and Berdahl, 1977) from an analytical perspective. Although the focus of this paper is atmospheric observations, much of the material concerning corrections for instrumental effects also applies to reduction of data acquired with SAM from analysis of solid samples. The Sample Analysis at Mars (SAM) instrument measures the composition of the martian atmosphere. Rigorous calibration of SAM's mass spectrometer was performed with relevant gas mixtures. Calibration included derivation of a new model to correct for electron multiplier effects. Volume mixing ratios for Ar and N2 obtained with SAM differ from those obtained with Viking. Differences between SAM and Viking volume mixing ratios are under investigation.

B. Franz, Heather; G. Trainer, Melissa; H. Wong, Michael; L. K. Manning, Heidi; C. Stern, Jennifer; R. Mahaffy, Paul; K. Atreya, Sushil; Benna, Mehdi; G. Conrad, Pamela; N. Harpold, Dan; A. Leshin, Laurie; A. Malespin, Charles; P. McKay, Christopher; Thomas Nolan, J.; Raaen, Eric

2014-06-01

33

Doppler optical mixing spectroscopy in multiparticle scattering fluids  

SciTech Connect

We discuss the basic scheme of laser Doppler optical mixing spectroscopy for the analysis of media with multiparticle scattering. It is shown that the Rayleigh scheme, in contrast to the heterodyne and differential schemes, is insensitive to the effects of multiparticle scattering. (laser applications and other aspects of quantum electronics)

Dubnishchev, Yu N [S S Kutateladze Institute of Thermophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

2011-03-31

34

Collection Efficiencies in an Aerodyne Aerosol Mass Spectrometer as a Function of Particle Phase for Laboratory Generated Aerosols  

Microsoft Academic Search

The Aerodyne Aerosol Mass Spectrometer (AMS) is a useful tool to study ambient particles. To be quantitative, the mass or (number) of particles detected by the AMS relative to the mass (or number) of particles sampled by the AMS, or the AMS collection efficiency (CE), must be known. Here we investigated the effect of particulate phase on AMS CE for

Brendan M. Matthew; Ann M. Middlebrook; Timothy B. Onasch

2008-01-01

35

Analysis of Bromination of Ethylbenzene Using a 45 MHz NMR Spectrometer: An Undergraduate Organic Chemistry Laboratory Experiment  

ERIC Educational Resources Information Center

A 45 MHz benchtop NMR spectrometer is used to identify the structures and determine the amount of 1-bromoethylbenzene and 1,1-dibromoethylbenzene produced from free-radical bromination of ethylbenzene. The experiment is designed for nonchemistry majors, specifically B.S. Biology students, in a predominantly undergraduate institution with…

Isaac-Lam, Meden F.

2014-01-01

36

The successful implementation of a licensed data management interface between a Sunquest® laboratory information system and an AB SCIEX™ mass spectrometer  

PubMed Central

Background: Interfacing complex laboratory equipment to laboratory information systems (LIS) has become a more commonly encountered problem in clinical laboratories, especially for instruments that do not have an interface provided by the vendor. Liquid chromatography-tandem mass spectrometry is a great example of such complex equipment, and has become a frequent addition to clinical laboratories. As the testing volume on such instruments can be significant, manual data entry will also be considerable and the potential for concomitant transcription errors arises. Due to this potential issue, our aim was to interface an AB SCIEX™ mass spectrometer to our Sunquest® LIS. Materials and Methods: We licensed software for the data management interface from the University of Pittsburgh, but extended this work as follows: The interface was designed so that it would accept a text file exported from the AB SCIEX™ × 5500 QTrap® mass spectrometer, pre-process the file (using newly written code) into the correct format and upload it into Sunquest® via file transfer protocol. Results: The licensed software handled the majority of the interface tasks with the exception of converting the output from the Analyst® software to the required Sunquest® import format. This required writing of a “pre-processor” by one of the authors which was easily integrated with the supplied software. Conclusions: We successfully implemented the data management interface licensed from the University of Pittsburgh. Given the coding that was required to write the pre-processor, and alterations to the source code that were performed when debugging the software, we would suggest that before a laboratory decides to implement such an interface, it would be necessary to have a competent computer programmer available. PMID:23599901

French, Deborah; Terrazas, Enrique

2013-01-01

37

Integral correlation measures for multiparticle physics  

E-print Network

We report on a considerable improvement in the technique of measuring multiparticle correlations via integrals over correlation functions. A modification of measures used in the characterization of chaotic dynamical sytems permits fast and flexible calculation of factorial moments and cumulants as well as their differential versions. Higher order correlation integral measurements even of large multiplicity events such as encountered in heavy ion collisons are now feasible. The change from ``ordinary'' to ``factorial'' powers may have important consequences in other fields such as the study of galaxy correlations and Bose-Einstein interferometry.

Eggers, H C; Carruthers, Peter A; Buschbeck, Brigitte

1993-01-01

38

Integral correlation measures for multiparticle physics  

E-print Network

We report on a considerable improvement in the technique of measuring multiparticle correlations via integrals over correlation functions. A modification of measures used in the characterization of chaotic dynamical sytems permits fast and flexible calculation of factorial moments and cumulants as well as their differential versions. Higher order correlation integral measurements even of large multiplicity events such as encountered in heavy ion collisons are now feasible. The change from ``ordinary'' to ``factorial'' powers may have important consequences in other fields such as the study of galaxy correlations and Bose-Einstein interferometry.

H. C. Eggers; P. Lipa; P. Carruthers; B. Buschbeck

1993-04-03

39

The SAGE spectrometer  

NASA Astrophysics Data System (ADS)

The SAGE spectrometer has been constructed for in-beam nuclear structure studies. SAGE combines a Ge-detector array and an electron spectrometer for detection of -rays and internal conversion electrons, respectively, and allows simultaneous observation of both electrons and -rays emitted from excited nuclei. SAGE is set up in the Accelerator Laboratory of the University of Jyväskylä and works in conjunction with the RITU gas-filled recoil separator and the GREAT focal-plane spectrometer allowing the use of the recoil-decay tagging method.

Pakarinen, J.; Papadakis, P.; Sorri, J.; Herzberg, R.-D.; Greenlees, P. T.; Butler, P. A.; Coleman-Smith, P. J.; Cox, D. M.; Cresswell, J. R.; Jones, P.; Julin, R.; Konki, J.; Lazarus, I. H.; Letts, S. C.; Mistry, A.; Page, R. D.; Parr, E.; Pucknell, V. F. E.; Rahkila, P.; Sampson, J.; Sandzelius, M.; Seddon, D. A.; Simpson, J.; Thornhill, J.; Wells, D.

2014-03-01

40

Monolithic spectrometer  

DOEpatents

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)

1998-01-01

41

Monolithic spectrometer  

DOEpatents

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. 6 figs.

Rajic, S.; Egert, C.M.; Kahl, W.K.; Snyder, W.B. Jr.; Evans, B.M. III; Marlar, T.A.; Cunningham, J.P.

1998-05-19

42

Anderson Localization for a Multi-Particle Quantum Graph  

NASA Astrophysics Data System (ADS)

We study a multi-particle quantum graph with random potential. Taking the approach of multiscale analysis, we prove exponential and strong dynamical localization of any order in the Hilbert-Schmidt norm near the spectral edge. Apart from the results on multi-particle systems, we also prove Lifshitz-type asymptotics for single-particle systems. This shows in particular that localization for single-particle quantum graphs holds under a weaker assumption on the random potential than previously known.

Sabri, Mostafa

2014-11-01

43

Simulation of background reduction and Compton depression in low-background HPGe spectrometer at a surface laboratory  

E-print Network

High-purity germanium detectors are well suited to analysis the radioactivity of samples. In order to reduce the environmental background, low-activity lead and oxygen free copper are installed outside of the probe to shield gammas, outmost is a plastic scintillator to veto the cosmic rays, and an anti-Compton detector can improve the Peak-to-Compton ratio. Using the GEANT4 tools and taking into account a detailed description of the detector, we optimize the sizes of the detectors to reach the design indexes. A group of experimental data from a HPGe spectrometer in using were used to compare with the simulation. As to new HPGe Detector simulation, considering the different thickness of BGO crystals and anti-coincidence efficiency, the simulation results show that the optimal thickness is 5.5cm, and the Peak-to-Compton ratio of 40K is raised to 1000 when the anti-coincidence efficiency is 0.85. As the background simulation, 15 cm oxygen-free copper plus 10 cm lead can reduce the environmental gamma rays to 0.0024 cps/100 cm3 Ge (50keV~2.8MeV), which is about 10-5 of environmental background.

ShunLi Niu; Xiao Cai; ZhenZhong Wu; YuGuang Xie; BoXiang Yu; ZhiGang Wang; Jian Fang; XiLei Sun; LiJun Sun; YingBiao Liu; Long Gao; Xuan Zhang; Hang Zhao; Li Zhou; JunGuang Lv; Tao Hu

2014-10-16

44

Simulation of background reduction and Compton depression in low-background HPGe spectrometer at a surface laboratory  

E-print Network

High-purity germanium detectors are well suited to analysis the radioactivity of samples. In order to reduce the environmental background, low-activity lead and oxygen free copper are installed outside of the probe to shield gammas, outmost is a plastic scintillator to veto the cosmic rays, and an anti-Compton detector can improve the Peak-to-Compton ratio. Using the GEANT4 tools and taking into account a detailed description of the detector, we optimize the sizes of the detectors to reach the design indexes. A group of experimental data from a HPGe spectrometer in using were used to compare with the simulation. As to new HPGe Detector simulation, considering the different thickness of BGO crystals and anti-coincidence efficiency, the simulation results show that the optimal thickness is 5.5cm, and the Peak-to-Compton ratio of 40K is raised to 1000 when the anti-coincidence efficiency is 0.85. As the background simulation, 15 cm oxygen-free copper plus 10 cm lead can reduce the environmental gamma rays to 0.0...

Niu, ShunLi; Wu, ZhenZhong; Xie, YuGuang; Yu, BoXiang; Wang, ZhiGang; Fang, Jian; Sun, XiLei; Sun, LiJun; Liu, YingBiao; Gao, Long; Zhang, Xuan; Zhao, Hang; Zhou, Li; Lv, JunGuang; Hu, Tao

2014-01-01

45

Acquisition of a Gas Chromatograph/Mass Spectrometer System for Laboratory Study of Prebiotic Organic Geochemical Processes on the Early Earth, Mars, and Meteorites  

NASA Technical Reports Server (NTRS)

This was a major equipment grant that provided funds ($72K) for purchase of a benchtop gas chromatograph-mass spectrometer (GC-MS) for use in experimental studies of prebiotic organic compounds. An Agilent model 689015973 GC-MS was purchased and installed in the PI's lab in August of 2003. The instrument is now being used for a variety of research projects. The primary use of the instrument is to analyze and quantify organic products of laboratory experiments conducted by the PI. One example is shown, which shows organic products (predominantly n-alkanes) formed during Fischer-Tropsch-type abiotic synthesis under hydrothermal conditions. The analytical capabilities of the GC- MS allowed identification of the numerous organic products of this as well as other laboratory experiments. A key use of the instrument in this research is that the mass spectrometer capabilities allow use of isotopically labeled reactants to trace the progress of reactions and evaluate background contaminants. collaborative projects with other scientists involved in exobiology & astrobiology research (e.g., Mitch Schulte, NASA Ames; Katrina Edwards, Woods Hole Oceanographic Institution). For instance, an analysis of membrane lipids of an lithoautotrophic iron-oxidizing bacteria being grown on basalt as a source of metabolic energy, a project where the instrument is being used to evaluate possible biomarker compounds from these organisms is shown. These iron oxidizers are thought to be similar to those living within the ocean crust, and are being investigated as possible analog organisms to those on the early Earth or crust of Mars. The instrument has also been used by an outside investigator (graduate student Brandon Canfeld, Arizona State University) for identification and isotopic characterization of experimental products of abiotic organic synthesis experiments he is conducting with Dr. John Holloway. analysis of quality control samples for other NASA-funded projects. For instance, an analysis of residual hydrocarbon contaminants on the internal surface of the shell of an atmospheric sounding rocket is shown. This analysis was used to help determine the source of the contaminating compounds. In the future, the instrument will continue to be used for quality control analysis in clean rooms and instrument construction facilities within the Laboratory for Atmospheric and Space Physics, where the GC-MS is housed.

McCollom, Thomas

2004-01-01

46

Correlation spectrometer  

DOEpatents

A correlation spectrometer can detect a large number of gaseous compounds, or chemical species, with a species-specific mask wheel. In this mode, the spectrometer is optimized for the direct measurement of individual target compounds. Additionally, the spectrometer can measure the transmission spectrum from a given sample of gas. In this mode, infrared light is passed through a gas sample and the infrared transmission signature of the gasses present is recorded and measured using Hadamard encoding techniques. The spectrometer can detect the transmission or emission spectra in any system where multiple species are present in a generally known volume.

Sinclair, Michael B. (Albuquerque, NM); Pfeifer, Kent B. (Los Lunas, NM); Flemming, Jeb H. (Albuquerque, NM); Jones, Gary D. (Tijeras, NM); Tigges, Chris P. (Albuquerque, NM)

2010-04-13

47

Multidimensional spectrometer  

DOEpatents

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)

2010-07-20

48

CD Spectrometer  

NSDL National Science Digital Library

In this activity, learners use a compact disc to make a spectrometer, an instrument used to measure properties of light. Learners use their spectrometer to view a continuous spectrum produced by fluorescent light. This lesson guide also includes instructions on how to build a spectroscope from a cereal box.

Paul Doherty

2000-01-01

49

Measurement of the Helicity Difference in gamma-->p-->-->ppi+pi? with the CLAS Spectrometer at Jefferson Laboratory  

SciTech Connect

The study of the properties of baryon resonances can provide us with hints to help us understand the structure of non-perturbative QCD and the effect of a particular resonance on polarization observables. The investigation of double-pion photoproduction data is needed to discover higher-lying states and their properties at and above W [approximate] 1.8 GeV. Therefore, the analysis of the helicity difference in gp gammap-->ppi+pi? will help us in our understanding of QCD.The CLAS g9a (FROST) experiment, as part of the N* spectroscopy program at Jefferson Laboratory, has accumulated photoproduction data using linearly and circularly polarized photons incident on a longitudinally-polarized butanol target in the photon energy range 0.3 to 2.4 GeV. The FROST experiment provides an important step toward a “complete” experiment for the reaction gammaN-->KY.In this contribution, the method to calculate the helicity difference for the reaction gammap-->ppi+pi? will be described and preliminary results will be discussed.

Sungkyun Park

2010-08-01

50

Multiparticle decoherence-free subspaces in extended systems  

SciTech Connect

We develop a method to determine spatial configurations to realize decoherence-free subspaces for spatially extended multiparticle systems. We have assumed normal reservoir behavior including translational invariance of the reservoir and preparation in stationary states or mixture thereof and weak Markovian system-reservoir coupling that requires energy transfer. One important outcome of our method is a proof that there does not exist a multiparticle decoherence-free subspace in such systems except in the limit that the spatial extent of the system becomes infinitesimal.

Karasik, Raisa I. [Applied Science and Technology, University of California, Berkeley, California 94720 (United States); Department of Chemistry and Berkeley Quantum Information Center, University of California, Berkeley, California 94720 (United States); Institute for Quantum Information Science, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Marzlin, Karl-Peter; Sanders, Barry C. [Institute for Quantum Information Science, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Whaley, K. Birgitta [Applied Science and Technology, University of California, Berkeley, California 94720 (United States); Department of Chemistry and Berkeley Quantum Information Center, University of California, Berkeley, California 94720 (United States)

2007-07-15

51

Advanced Mass Spectrometers for Hydrogen Isotope Analyses  

SciTech Connect

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.

2001-08-01

52

Advanced Mass Spectrometers for Hydrogen Isotope Analyses  

Microsoft Academic Search

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

2001-01-01

53

Exploring the Capabilities of the Anti-Coincidence Shield of the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) Spectrometer to Study Solar Flares  

NASA Astrophysics Data System (ADS)

The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) is a European Space Agency hard X-ray/ ?-ray observatory for astrophysics, covering photon energies from 15 keV to 10 MeV. It was launched in 2002, and since then the Bismuth Germanate (BGO) detectors of the Anti-Coincidence Shield (ACS) of the Spectrometer on INTEGRAL (SPI) have detected many hard X-ray (HXR) bursts from the Sun, producing light curves at photon energies above ? 100 keV. The spacecraft has a highly elliptical orbit, providing long uninterrupted observing (about 90 % of the orbital period) with nearly constant background due to the shorter time needed to cross Earth's radiation belts. However, because of technical constraints, INTEGRAL cannot be pointed at the Sun, and high-energy solar photons are always detected in nonstandard observation conditions. To make the data useable for solar studies, we have undertaken a major effort to specify the observing conditions through Monte Carlo simulations of the response of ACS for several selected flares. We checked the performance of the model employed for the Monte Carlo simulations using the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations for the same sample of solar flares. We conclude that although INTEGRAL was not designed to perform solar observations, ACS is a useful instrument for solar-flare research. In particular, its relatively large effective area allows determining good-quality HXR/ ?-ray light curves for X- and M-class solar flares and, in some cases, probably also for C-class flares.

Rodríguez-Gasén, R.; Kiener, J.; Tatischeff, V.; Vilmer, N.; Hamadache, C.; Klein, K.-L.

2014-05-01

54

The LASS (Larger Aperture Superconducting Solenoid) spectrometer  

SciTech Connect

LASS is the acronym for the Large Aperture Superconducting Solenoid spectrometer which is located in an rf-separated hadron beam at the Stanford Linear Accelerator Center. This spectrometer was constructed in order to perform high statistics studies of multiparticle final states produced in hadron reactions. Such reactions are frequently characterized by events having complicated topologies and/or relatively high particle multiplicity. Their detailed study requires a spectrometer which can provide good resolution in momentum and position over almost the entire solid angle subtended by the production point. In addition, good final state particle identification must be available so that separation of the many kinematically-overlapping final states can be achieved. Precise analyses of the individual reaction channels require high statistics, so that the spectrometer must be capable of high data-taking rates in order that such samples can be acquired in a reasonable running time. Finally, the spectrometer must be complemented by a sophisticated off-line analysis package which efficiently finds tracks, recognizes and fits event topologies and correctly associates the available particle identification information. This, together with complicated programs which perform specific analysis tasks such as partial wave analysis, requires a great deal of software effort allied to a very large computing capacity. This paper describes the construction and performance of the LASS spectrometer, which is an attempt to realize the features just discussed. The configuration of the spectrometer corresponds to the data-taking on K and K interactions in hydrogen at 11 GeV/c which took place in 1981 and 1982. This constitutes a major upgrade of the configuration used to acquire lower statistics data on 11 GeV/c K p interactions during 1977 and 1978, which is also described briefly.

Aston, D.; Awaji, N.; Barnett, B.; Bienz, T.; Bierce, R.; Bird, F.; Bird, L.; Blockus, D.; Carnegie, R.K.; Chien, C.Y.

1986-04-01

55

Spectrometer gun  

DOEpatents

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)

1985-01-01

56

Spectrometer gun  

DOEpatents

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.

1981-11-03

57

Next Generation Multi-particle event generators for the MSSM  

E-print Network

We present a next generation of multi-particle Monte Carlo (MC) Event generators for LHC and ILC for the MSSM, namely the three program packages Madgraph/MadEvent, WHiZard/O'Mega and Sherpa/Amegic++. The interesting but difficult phenomenology of supersymmetric models at the upcoming colliders demands a corresponding complexity and maturity from simulation tools. This includes multi-particle final states, reducible and irreducible backgrounds, spin correlations, real emission of photons and gluons, etc., which are incorporated in the programs presented here. The framework of a model with such a huge particle content and as complicated as the MSSM makes strenuous tests and comparison of codes inevitable. Various tests show agreement among the three different programs; the tables of cross sections produced in these tests may serve as a future reference for other codes. Furthermore, first MSSM physics analyses performed with these programs are presented here.

J. Reuter; K. Hagiwara; W. Kilian; F. Krauss; T. Ohl; T. Plehn; D. Rainwater; S. Schumann

2006-02-02

58

The Spectrometer  

ERIC Educational Resources Information Center

In the fall of 1999 I was shown an Ocean Optics spectrometer-in-the-computer at St. Patricks College at Maynooth, Ireland, and thought that I had seen heaven. Of course, it could not resolve the sodium D-lines (I had done that many years before with a homemade wire diffraction grating), and I began to realize that inside was some familiar old…

Greenslade, Thomas B., Jr.

2012-01-01

59

Mass spectrometers and atomic oxygen  

NASA Technical Reports Server (NTRS)

The likely role of atmospheric atomic oxygen in the recession of spacecraft surfaces and in the shuttle glow has revived interest in the accurate measurement of atomic oxygen densities in the upper atmosphere. The Air Force Geophysics Laboratory is supplying a quadrupole mass spectrometer for a materials interactions flight experiment being planned by the Johnson Space Center. The mass spectrometer will measure the flux of oxygen on test materials and will also identify the products of surface reactions. The instrument will be calibrated at a new facility for producing high energy beams of atomic oxygen at the Los Alamos National Laboratory. The plans for these calibration experiments are summarized.

Hunton, D. E.; Trzcinski, E.; Cross, J. B.; Spangler, L. H.; Hoffbauer, M. H.; Archuleta, F. H.; Visentine, J. T.

1987-01-01

60

A Mass Spectrometer Simulator in Your Computer  

ERIC Educational Resources Information Center

Introduced to study components of ionized gas, the mass spectrometer has evolved into a highly accurate device now used in many undergraduate and research laboratories. Unfortunately, despite their importance in the formation of future scientists, mass spectrometers remain beyond the financial reach of many high schools and colleges. As a result,…

Gagnon, Michel

2012-01-01

61

Investigating the multiparticle decay in intermediate energy heavy ion collisions  

SciTech Connect

Exclusive measurements of light charged products (LCP) in the [sup 132]Xe+[sup 197]Au collisions at 44 MeV/nucleon have been performed using MEDEA 4[pi] detection system. The admixture of each partricle type into the LCP multiplicity is found to be almost independent of the impact parameter. The data are analyzed with a formalism where the fluctuations of the multiparticle decay are described by uncorrelated Poissonian statistical distributions. The impact parameter filtering is performed using the LCP multiplicity. Self-correlation and impact parameter averagining effects are identified. The dominance of the statistical contribution in the fluctuations of the LCP multiplicity is deduced.

Del Zoppo, A.; Alba, R.; Coniglione, R.; Agodi, C.; Bellia, G.; Finocchiaro, P.; Loukachine, K.; Maiolino, C.; Migneco, E.; Peghaire, A.; Piattelli, P.; Santonocito, D.; Sapienza, P. (INFN Laboratorio Nazionale del Sud, Via S. Sofia 44, 95123 Catania (Italy) Dipartimento di Fisica dell'Universita di Catania (Italy) GANIL, Caen (France))

1994-06-01

62

Small angle spectrometers: Summary  

SciTech Connect

Aspects of experiments at small angles at the Superconducting Super Collider are considered. Topics summarized include a small angle spectrometer, a high contingency spectrometer, dipole and toroid spectrometers, and magnet choices. (LEW)

Courant, E.; Foley, K.J.; Schlein, P.E.; Rosner, J.; Slaughter, J.; Bromberg, C.; Jones, L.; Garren, A.; Groom, D.; Johnson, D.E.

1986-01-01

63

Quasi-power laws in multiparticle production processes  

E-print Network

We review the ubiquitous presence in multiparticle production processes of quasi-power law distributions (i.e., distributions following pure power laws for large values of the argument but remaining finite, usually exponential, for small values). Special emphasis is placed on the conjecture that this reflects the presence in the produced hadronic systems of some intrinsic fluctuations. If described by parameter q they form, together with the scale parameter $T$ ("temperature"), basis of Tsallis distribution, ${f(X)\\sim [1 - (1-q)X/T]^{1/(1-q)}}$, frequently used to describe the relevant distributions (the X being usually a transverse momentum). We discuss the origin of such quasi-power law behavior based on our experience with the description of multiparticle production processes. In particular, we discuss Tsallis distribution with complex nonextensivity parameter q and argue that it is needed to describe log-oscillations as apparently observed in recent data on large momentum distributions in very high energy p-p collisions.

Grzegorz Wilk; Zbigniew W?odarczyk

2015-03-30

64

Multiparticle Higgs and vector boson amplitudes at threshold  

NASA Astrophysics Data System (ADS)

In a spontaneously broken gauge theory we consider (sub)-processes in which one virtual intermediate state (it can be a Higgs or a gauge field) produces many on-shell Higgses and massive vector bosons. In the kinematic regime where all final states are produced on their mass threshold, we show how to compute iteratively all tree-level amplitudes involving an arbitrary number n of Higgs bosons and m of longitudinal vector bosons in the final state, and list the amplitudes coefficients for up to n=32 and m=32. Wefindthattheseamplitudesexhibitfactorialgrowthnotonlyinthenumberof scalar fields, but also in the number of longitudinal gauge fields, ~ n! m!. This growth is not expected to disappear at loop-level in the fixed-order perturbation theory. We conclude that at energies accessible at the next generation of hadron colliders, such as the 50-100 TeV FCC, where is sufficient to produce ?1 /? W of W, Z and H, perturbation theory breaks down when applied to the multiparticle electroweak production, at least near the kinematic multiparticle mass threshold where the electroweak gauge-Higgs sector becomes strongly coupled.

Khoze, Valentin V.

2014-07-01

65

Mass spectrometers: instrumentation  

NASA Astrophysics Data System (ADS)

Developments in mass spectrometry instrumentation over the past three years are reviewed. The subject is characterized by an enormous diversity of designs, a high degree of competition between different laboratories working with either different or similar techniques and by extremely rapid progress in improving analytical performance. Instruments can be grouped into genealogical charts based on their physical and conceptual interrelationships. This is illustrated using mass analyzers of different types. The time course of development of particular instrumental concepts is illustrated in terms of the s-curves typical of cell growth. Examples are given of instruments which are at the exponential, linear and mature growth stages. The prime examples used are respectively: (i) hybrid instruments designed to study reactive collisions of ions with surfaces: (ii) the Paul ion trap; and (iii) the triple quadrupole mass spectrometer. In the area of ion/surface collisions, reactive collisions such as hydrogen radical abstraction from the surface by the impinging ion are studied. They are shown to depend upon the chemical nature of the surface through the use of experiments which utilize self-assembled monolayers as surfaces. The internal energy deposited during surface-induced dissociation upon collision with different surfaces in a BEEQ instrument is also discussed. Attention is also given to a second area of emerging instrumentation, namely technology which allows mass spectrometers to be used for on-line monitoring of fluid streams. A summary of recent improvements in the performance of the rapidly developing quadrupole ion trap instrument illustrates this stage of instrument development. Improvements in resolution and mass range and their application to the characterization of biomolecules are described. The interaction of theory with experiment is illustrated through the role of simulations of ion motion in the ion trap. It is emphasized that mature instruments play a dominant role in most work using mass spectrometers. This is illustrated with recent results on the chemistry of C+.60 including the formation of covalent adducts with aromatic compounds. Quantitative analysis of methylated nucleosides and structural studies of the anti-cancer drug taxol are also discussed. A compendium of mass spectrometers constructed over the past three years is provided. This includes a variety of hybrid instruments, combinations of sector mass spectrometers with traps, instruments designed to study collision dynamics, and many more.

Cooks, R. G.; Hoke, S. H., II; Morand, K. L.; Lammert, S. A.

1992-09-01

66

The effect of a computer-based, spectrometer tutorial on chemistry students' learning in a UV/vis spectroscopy laboratory experiment  

NASA Astrophysics Data System (ADS)

It is common for fairly sophisticated instruments to be used in undergraduate, general chemistry, laboratory courses. Typically, these instruments are treated as incidental to the experiment: students are given extensive operating instructions, but told little or nothing about how they work, because understanding the instruments themselves is not an objective of the course. The implicit assumption is that chemical principles can be deduced simply from accurate data. However, cognitive load theory (Sweller, 1988, 2005) predicts it would be more difficult for students with limited prior knowledge to make sense of their data if they do not know how measurements made with the instruments are actually derived from their physical sample. Therefore, treating laboratory instruments as incidental may actually make it more difficult for students to learn the chemical concepts that underlie the data they collect. This experimental study was intended to determine whether a multimedia tutorial, designed to help students understand how a UV/vis spectrophotometer works, brings about any changes in performance on a laboratory experiment about food dye solutions. Working in pairs, 750 students were randomly assigned to receive either the tutorial (treatment) or an alternative task (comparison) as an introduction to an experiment that was a regular part of an undergraduate, general chemistry, laboratory course. Students' responses to all laboratory questions were collected and scored. The amount of time students spent on each laboratory task was collected as well. On average, treatment students completed many of the laboratory tasks significantly more quickly than comparison students. Treatment students typically also provided more concise responses to many of the laboratory questions. Unfortunately, no differences were found in scores on laboratory questions. Therefore, while there is evidence the tutorial helped students learn more efficiently, evidence could not be found that they learned more deeply. Potential explanations for these results and their implications are discussed.

Wood, Nathan Brent

67

Multiparticle entanglement in graph-diagonal states: Necessary and sufficient conditions for four qubits  

SciTech Connect

The characterization of genuine multiparticle entanglement is important for entanglement theory as well as experimental studies related to quantum-information theory. Here, we completely characterize genuine multiparticle entanglement for four-qubit states diagonal in the cluster-state basis. In addition, we give a complete characterization of multiparticle entanglement for all five-qubit graph states mixed with white noise, for states diagonal in the basis corresponding to the five-qubit Y-shaped graph, and for a family of graph states with an arbitrary number of qubits.

Guehne, Otfried [Naturwissenschaftlich-Technische Fakultaet, Universitaet Siegen, Walter-Flex-Strasse 3, D-57068 Siegen (Germany); Jungnitsch, Bastian; Moroder, Tobias [Institut fuer Quantenoptik und Quanteninformation, Oesterreichische Akademie der Wissenschaften, Technikerstrasse 21A, A-6020 Innsbruck (Austria); Weinstein, Yaakov S. [Quantum Information Science Group, MITRE, 260 Industrial Way West, Eatontown, New Jersey 07724 (United States)

2011-11-15

68

Monte Carlo model for multiparticle production at ultrarelativistic energies  

SciTech Connect

The Monte Carlo parton string model for multiparticle production in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions at high energies is described. An adequate choice of the parameters in the model gives the possibility of recovering the main results of the dual parton model, with the advantage of treating both hadron and nuclear interactions on the same footing, reducing them to interactions between partons. Also the possibility of considering both soft and hard parton interactions is introduced. Comparison to the available experimental data on nucleon and nuclear collisions, together with predictions for mean multiplicities, net baryon rapidity distributions, and the temporal evolution of meson densities for heavy ion collisions at the CERN Super Proton Synchrotron (194A GeV) and the BNL Relativistic Heavy Ion Collider (200{ital A} GeV) are presented. Furthermore, predictions for charm production at these energies are given.

Amelin, N.S.; Stoecker, H.; Greiner, W. [Institut fuer Theoretische Physik, Universitaet Frankfurt, Postfach 111932, D-6054 Frankfurt am Main 11 (Germany)] [Institut fuer Theoretische Physik, Universitaet Frankfurt, Postfach 111932, D-6054 Frankfurt am Main 11 (Germany); Armesto, N.; Braun, M.A.; Pajares, C. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15706-Santiago de Compostela (Spain)] [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15706-Santiago de Compostela (Spain)

1995-07-01

69

Simulating strongly correlated multiparticle systems in a truncated Hilbert space  

SciTech Connect

Representing a strongly interacting multiparticle wave function in a finite product basis leads to errors. Simple rescaling of the contact interaction can preserve the low-lying energy spectrum and long-wavelength structure of wave functions in one-dimensional systems and thus correct for the basis set truncation error. The analytic form of the rescaling is found for a two-particle system where the rescaling is exact. A detailed comparison between finite Hilbert space calculations and exact results for up to five particles show that rescaling can significantly improve the accuracy of numerical calculations in various external potentials. In addition to ground-state energies, the low-lying excitation spectrum, density profile, and correlation functions are studied. The results give a promising outlook for numerical simulations of trapped ultracold atoms.

Ernst, Thomas; Hallwood, David W.; Gulliksen, Jake; Brand, Joachim [New Zealand Institute for Advanced Study and Centre for Theoretical Chemistry and Physics, Massey University, Private Bag 102904, North Shore, Auckland 0745 (New Zealand); Meyer, Hans-Dieter [Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany)

2011-08-15

70

Backtracking of colloids: a multiparticle collision dynamics simulation study  

E-print Network

The role of sound in the dynamics of mesoscale systems is typically neglected, since frequently the associated time scales are much smaller than all the other time scales of interest. However, for sufficiently small objects embedded in a solvent with a sufficiently small sound velocity, sound can play a crucial role. In particular, behavior resembling viscoelasticity has been theoretically predicted for non-viscoelastic fluids. This effect is due to the interference of the propagation of sound waves caused by the solute particle's motion and hydrodynamic vortex formation. We demonstrate this effect, known as backtracking, in computer simulations employing the method of multiparticle collision dynamics. We systematically study the influence of sound on the dynamics of the solute particle, and find that it disappears in the long-time limit. Thus, we confirm that sonic effects at the single-particle level can be neglected at sufficiently long times.

M. Belushkin; R. G. Winkler; G. Foffi

2011-08-26

71

Entanglement Polytopes: Multiparticle Entanglement from Single-Particle Information  

E-print Network

Entangled many-body states are an essential resource for quantum computing and interferometry. Determining the type of entanglement present in a system usually requires access to an exponential number of parameters. We show that in the case of pure multi-particle quantum states, features of the global entanglement can already be extracted from local information alone. This is achieved by associating with any given class of entanglement an entanglement polytope---a geometric object which characterizes the single-particle states compatible with that class. Our results, applicable to systems of arbitrary size and statistics, give rise to local witnesses for global pure-state entanglement, and can be generalized to states affected by low levels of noise.

Michael Walter; Brent Doran; David Gross; Matthias Christandl

2014-11-14

72

Multiparticle Simulation of Intrabeam Scattering for SuperB  

SciTech Connect

In this communication we present the structure of a multiparticle tracking code to investigate intrabeam scattering effects in low emittance colliders. Simulation results obtained with particular reference to the SuperB parameters are compared with those of conventional IBS theories.and with those of a novel semi-analythical model able to predict IBS effect in terms of emittance growths. Intrabeam scattering (IBS) is associated with multiple small angle scattering events leading to emittance growth. In most electron storage rings, the growth rates arising from IBS are usually much longer than damping times due to synchrotron radiation, and its effect is not observed. However, IBS growth rates increase with bunch charge density, and for machines such as SuperB, that operate with high bunch charges and very low emittances, the IBS growth rates can be large enough to observe significant emittance increase. Several formalisms have been developed for calculating IBS growth rates in storage rings, notably those by Piwinski, Bjorken and Mtingwa, and their high energy approximations. Calculations show that IBS should be manageable in both SuperB rings. However these analytical models, based on Gaussian bunch distributions, cannot investigate some interesting aspects of IBS such as its impact during the damping process and its effect on the beam distribution. We developed a multiparticle tracking code, based on the Zenkevich-Bolshakov algorithm, to investigate these effects. In this communication we present the structure of the code and some simulation results obtained with particular reference to the SuperB parameters. Simulation results are compared with those of conventional IBS theories.

Biagini, M.; Boscolo, M.; Demma, T.; /Frascati; Chao, A.W.; Bane, K.L.F.; Pivi, M.T.F.; /SLAC

2012-04-27

73

Efficient localization bounds in a continuous multi-particle Anderson model with long-range interaction  

E-print Network

We establish strong dynamical localization for a class of multi-particle Anderson models in a Euclidean space with an alloy-type random potential and a sub-exponentially decaying interaction of infinite range. For the first time in the mathematical literature, the uniform decay bounds on the eigenfunction correlators at low energies are proved, in the multi-particle continuous configuration space, in the norm-distance and not in the Hausdorff pseudo-metric.

Victor Chulaevsky

2014-07-17

74

Studies of nuclear rotational bands with the spin spectrometer  

Microsoft Academic Search

In the last few years increasingly sophisticated gamma-ray spectrometer arrays have been built at a number of laboratories around the world. These instruments, coupled with versatile heavy-ion accelerators, are capable of probing the detailed behaviour of atomic nuclei under extreme conditions of angular momentum and temperature. Characteristics of one such detector array, the Spin Spectrometer at Oak Ridge National Laboratory,

L. L. Riedinger; M. P. Carpenter; L. H. Courtney; V. P. Janzen

1987-01-01

75

Multidetector calibration for mass spectrometers  

Microsoft Academic Search

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: (i) peak-shift experiments and (ii) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements

C. Bayne; D. Donohue; R. Fiedler

1994-01-01

76

Multidetector calibration for mass spectrometers  

Microsoft Academic Search

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

C. K. Bayne; D. L. Donohue; R. Fiedler

1994-01-01

77

A transmission oscillator ultrasonic spectrometer  

NASA Technical Reports Server (NTRS)

A continuous wave ultrasonic instrument capable of measuring very small changes in acoustic attenuation and phase velocity is described. This transmission oscillator ultrasonic spectrometer (TOUS) exhibits high sensitivity because it oscillates marginally. In spite of this high sensitivity, the TOUS system is relatively simple, compact, and inexpensive. These features suggest that the TOUS is suitable not only for precise laboratory measurements of the physical properties of materials, but also for field applications in nondestructive testing.

Conradi, M. S.; Miller, J. G.; Heyman, J. S.

1974-01-01

78

Tropospheric Emission Spectrometer and Airborne Emission Spectrometer  

NASA Technical Reports Server (NTRS)

The Tropospheric Emission Spectrometer (TES) is an instrument being developed for the NASA Earth Observing System Chemistry Platform. TES will measure the distribution of ozone and its precursors in the lower atmosphere. The Airborne Emission Spectrometer (AES) is an aircraft precursor to TES. Applicable descriptions are given of instrument design, technology challenges, implementation and operations for both.

Glavich, T.; Beer, R.

1996-01-01

79

Automated mass spectrometer grows up  

SciTech Connect

In 1980 we reported the development of an automated mass spectrometer for large scale batches of samples enriched in nitrogen-15 as ammonium salts. Since that time significant technical progress has been made in the instrument. Perhaps more significantly, administrative and institutional changes have permitted the entire effort to be transferred to the private sector from its original base at the Los Alamos National Laboratory. This has ensured the continuance of a needed service to the international scientific community as revealed by a development project at a national laboratory, and is an excellent example of beneficial technology transfer to private industry.

McInteer, B.B.; Montoya, J.G.; Stark, E.E.

1984-01-01

80

Galileo Ultraviolet Spectrometer experiment  

Microsoft Academic Search

The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113–432 nm with a wavelength

C. W. Hord; A. I. F. Stewart; C. A. Barth; L. W. Esposito; G. E. Thomas; B. R. Sandel; D. M. Hunten; A. L. Broadfoot; D. E. Shemansky; J. M. Ajello; R. A. West

1992-01-01

81

Galileo Ultraviolet Spectrometer experiment  

Microsoft Academic Search

The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113-432 nm with a wavelength

C. W. Hord; W. E. McClintock; A. I. F. Stewart; C. A. Barth; L. W. Esposito; G. E. Thomas; B. R. Sandel; D. M. Hunten; A. L. Broadfoot; D. E. Shemansky

1992-01-01

82

On Statistical Mechanics Developments of Clan Concept in Multiparticle Production  

E-print Network

Clan concept has been introduced in multiparticle dynamics in order to interpret the wide occurrence of negative binomial (NB) regularity in n-charged particle multiplicity distributions (MDs) in various high energy collisions. The centrality of clan concept led to the attempt to justify its occurrence within a statistical model of clan formation and evolution. In this framework all thermodynamical potentials have been explicitly calculated in terms of NB parameters. Interestingly it was found that NB parameter k corresponds to the one particle canonical partition function. The goal of this paper is to explore a possible temperature and volume dependence of parameter k in various classes of events in high energy hadron-hadron collisions. It is shown that the existence of a phase transition at parton level from the ideal clan gas associated to the semihard component with k>1 to the ideal clan gas of the hard component with k<1 implies a discontinuity in the average number of particles at hadron level.

M. Brambilla; A. Giovannini; R. Ugoccioni

2007-12-16

83

Thermostat for nonequilibrium multiparticle-collision-dynamics simulations  

NASA Astrophysics Data System (ADS)

Multiparticle collision dynamics (MPC), a particle-based mesoscale simulation technique for complex fluid, is widely employed in nonequilibrium simulations of soft matter systems. To maintain a defined thermodynamic state, thermalization of the fluid is often required for certain MPC variants. We investigate the influence of three thermostats on the nonequilibrium properties of a MPC fluid under shear or in Poiseuille flow. In all cases, the local velocities are scaled by a factor, which is either determined via a local simple scaling approach (LSS), a Monte Carlo-like procedure (MCS), or by the Maxwell-Boltzmann distribution of kinetic energy (MBS). We find that the various scaling schemes leave the flow profile unchanged and maintain the local temperature well. The fluid viscosities extracted from the various simulations are in close agreement. Moreover, the numerically determined viscosities are in remarkably good agreement with the respective theoretically predicted values. At equilibrium, the calculation of the dynamic structure factor reveals that the MBS method closely resembles an isothermal ensemble, whereas the MCS procedure exhibits signatures of an adiabatic system at larger collision-time steps. Since the velocity distribution of the LSS approach is non-Gaussian, we recommend to apply the MBS thermostat, which has been shown to produce the correct velocity distribution even under nonequilibrium conditions.

Huang, Chien-Cheng; Varghese, Anoop; Gompper, Gerhard; Winkler, Roland G.

2015-01-01

84

Thermostat for nonequilibrium multiparticle-collision-dynamics simulations.  

PubMed

Multiparticle collision dynamics (MPC), a particle-based mesoscale simulation technique for complex fluid, is widely employed in nonequilibrium simulations of soft matter systems. To maintain a defined thermodynamic state, thermalization of the fluid is often required for certain MPC variants. We investigate the influence of three thermostats on the nonequilibrium properties of a MPC fluid under shear or in Poiseuille flow. In all cases, the local velocities are scaled by a factor, which is either determined via a local simple scaling approach (LSS), a Monte Carlo-like procedure (MCS), or by the Maxwell-Boltzmann distribution of kinetic energy (MBS). We find that the various scaling schemes leave the flow profile unchanged and maintain the local temperature well. The fluid viscosities extracted from the various simulations are in close agreement. Moreover, the numerically determined viscosities are in remarkably good agreement with the respective theoretically predicted values. At equilibrium, the calculation of the dynamic structure factor reveals that the MBS method closely resembles an isothermal ensemble, whereas the MCS procedure exhibits signatures of an adiabatic system at larger collision-time steps. Since the velocity distribution of the LSS approach is non-Gaussian, we recommend to apply the MBS thermostat, which has been shown to produce the correct velocity distribution even under nonequilibrium conditions. PMID:25679742

Huang, Chien-Cheng; Varghese, Anoop; Gompper, Gerhard; Winkler, Roland G

2015-01-01

85

Multi-particle collision dynamics modeling of viscoelastic fluids  

E-print Network

In order to investigate the rheological properties of viscoelastic fluids by mesoscopic hydrodynamics methods, we develop a multi-particle collision dynamics (MPC) model for a fluid of harmonic dumbbells. The algorithm consists of alternating streaming and collision steps. The advantage of the harmonic interactions is that the integration of the equations of motion in the streaming step can be performed analytically. Therefore, the algorithm is computationally as efficient as the original MPC algorithm for Newtonian fluids. The collision step is the same as in the original MPC method. All particles are confined between two solid walls moving oppositely, so that both steady and oscillatory shear flows can be investigated. Attractive wall potentials are applied to obtain a nearly uniform density everywhere in the simulation box. We find that both in steady and oscillatory shear flow, a boundary layer develops near the wall, with a higher velocity gradient than in the bulk. The thickness of this layer is proportional to the average dumbbell size. We determine the zero-shear viscosities as a function of the spring constant of the dumbbells and the mean free path. For very high shear rates, a very weak ``shear thickening'' behavior is observed. Moreover, storage and loss moduli are calculated in oscillatory shear, which show that the viscoelastic properties at low and moderate frequencies are consistent with a Maxwell fluid behavior. We compare our results with a kinetic theory of dumbbells in solution, and generally find good agreement.

Yu-Guo Tao; Ingo O. Goetze; Gerhard Gompper

2008-02-15

86

An industrial hygiene survey of acetonitrile using a miniature quadrupole mass spectrometer  

E-print Network

in the laboratory, such as the mass spectrometer. These advances include recent development of a miniature multipole mass spectrometer that may be useful for direct measurement of contamination in the field. Two goals were achieved in this research. First...

Bruss, Stacy M

1999-01-01

87

Identification of new transformation products during enzymatic treatment of tetracycline and erythromycin antibiotics at laboratory scale by an on-line turbulent flow liquid-chromatography coupled to a high resolution mass spectrometer LTQ-Orbitrap.  

PubMed

This work describes the formation of transformation products (TPs) by the enzymatic degradation at laboratory scale of two highly consumed antibiotics: tetracycline (Tc) and erythromycin (ERY). The analysis of the samples was carried out by a fast and simple method based on the novel configuration of the on-line turbulent flow system coupled to a hybrid linear ion trap - high resolution mass spectrometer. The method was optimized and validated for the complete analysis of ERY, Tc and their transformation products within 10 min without any other sample manipulation. Furthermore, the applicability of the on-line procedure was evaluated for 25 additional antibiotics, covering a wide range of chemical classes in different environmental waters with satisfactory quality parameters. Degradation rates obtained for Tc by laccase enzyme and ERY by EreB esterase enzyme without the presence of mediators were ?78% and ?50%, respectively. Concerning the identification of TPs, three suspected compounds for Tc and five of ERY have been proposed. In the case of Tc, the tentative molecular formulas with errors mass within 2 ppm have been based on the hypothesis of dehydroxylation, (bi)demethylation and oxidation of the rings A and C as major reactions. In contrast, the major TP detected for ERY has been identified as the "dehydration ERY-A", with the same molecular formula of its parent compound. In addition, the evaluation of the antibiotic activity of the samples along the enzymatic treatments showed a decrease around 100% in both cases. PMID:24972175

Llorca, Marta; Rodríguez-Mozaz, Sara; Couillerot, Olivier; Panigoni, Karine; de Gunzburg, Jean; Bayer, Sally; Czaja, Rico; Barceló, Damià

2015-01-01

88

Handheld spectrometers: the state of the art  

NASA Astrophysics Data System (ADS)

"Small" spectrometers fall into three broad classes: small versions of laboratory instruments, providing data, subsequently processed on a PC; dedicated analyzers, providing actionable information to an individual operator; and process analyzers, providing quantitative or semi-quantitative information to a process controller. The emphasis of this paper is on handheld dedicated analyzers. Many spectrometers have historically been large, possible fragile, expensive and complicated to use. The challenge over the last dozen years, as instruments have moved into the field, has been to make spectrometers smaller, affordable, rugged, easy-to-use, but most of all capable of delivering actionable results. Actionable results can dramatically improve the efficiency of a testing process and transform the way business is done. There are several keys to this handheld spectrometer revolution. Consumer electronics has given us powerful mobile platforms, compact batteries, clearly visible displays, new user interfaces, etc., while telecomm has revolutionized miniature optics, sources and detectors. While these technologies enable miniature spectrometers themselves, actionable information has demanded the development of rugged algorithms for material confirmation, unknown identification, mixture analysis and detection of suspicious materials in unknown matrices. These algorithms are far more sophisticated than the `correlation' or `dot-product' methods commonly used in benchtop instruments. Finally, continuing consumer electronics advances now enable many more technologies to be incorporated into handheld spectrometers, including Bluetooth, wireless, WiFi, GPS, cameras and bar code readers, and the continued size shrinkage of spectrometer `engines' leads to the prospect of dual technology or `hyphenated' handheld instruments.

Crocombe, Richard A.

2013-05-01

89

Multiparticle SUSY simulations at LHC & ILC: Off-Shell effects, interferences and radiative corrections  

E-print Network

The interesting but difficult phenomenology of supersymmetric models at the LHC and ILC demands a corresponding complexity and maturity from simulation tools. This includes multi-particle final states, reducible and irreducible backgrounds, spin correlations, real emission of photons and gluons, virtual corrections etc. Most of these topics are included in the multi-particle Monte Carlo (MC) Event generators Madgraph, WHIZARD and Sherpa. A comparison of these codes is shown, with a special focus on the new release of WHIZARD. I show examples for the necessity of considering full matrix elements with all off-shell effects and interferences for multi-particle final states in supersymmetric models and give a status report on ongoing projects for simulations of SUSY processes at the LHC with these codes, including all of the abovementioned corrections.

Jurgen Reuter

2007-09-28

90

Generic framework for anisotropic flow analyses with multi-particle azimuthal correlations  

E-print Network

We present a new generic framework which enables exact and fast evaluation of all multi-particle azimuthal correlations. The framework can be readily used along with a correction framework for systematic biases in anisotropic flow analyses due to various detector inefficiencies. A new recursive algorithm has been developed for higher order correlators for the cases where their direct implementation is not feasible. We propose and discuss new azimuthal observables for anisotropic flow analyses which can be measured for the first time with our new framework. Effects of finite detector granularity on multi-particle correlations are quantified and discussed in detail. We point out the existence of a systematic bias in traditional differential flow analyses which stems solely from the applied selection criteria on particles used in the analyses, and is also present in the ideal case when only flow correlations are present. Finally, we extend the applicability of our generic framework to the case of differential multi-particle correlations.

Ante Bilandzic; Christian Holm Christensen; Kristjan Gulbrandsen; Alexander Hansen; You Zhou

2013-12-20

91

Multi-particle assembled porous nanostructured MgO: its application in fluoride removal  

NASA Astrophysics Data System (ADS)

In this article, a simple and economical route based on ethylene glycol mediated process was developed to synthesize one-dimensional (1D) multiparticle assembled nanostructured MgO using magnesium acetate and urea as reactants. Porous multiparticle chain-like MgO has been synthesized by the calcination of a solvothermally derived single nanostructured precursor. The prepared products were characterized by an x-ray diffraction (XRD) pattern, thermogravimetry, scanning/transmission electron microscopy (SEM/TEM) and N2 adsorption (BET). As a proof of concept, the porous multiparticle chain-like MgO has been applied in a water treatment for isolated and rural communities, and it has exhibited an excellent adsorption capability to remove fluoride in waste water. In addition, this method could be generalized to prepare other 1D nanostructures with great potential for various attractive applications.

Gangaiah, Vijayakumar; Siddaramanna, Ashoka; Thimanna Chandrappa, Gujjarahalli

2014-12-01

92

Data acquisition system for the HHIRF spin spectrometer  

Microsoft Academic Search

The Spin Spectrometer at the Holifield Heavy Ion Research Facility (HHIRF) is a multidetector ..gamma..-ray spectrometer consisting of 72 separate NaI detector elements closely packed in a 4..pi.. geometry. The basic apparatus was constructed at Washington University and has been installed and implemented at the HHIRF at Oak Ridge National Laboratory. The spectrometer was designed especially for the investigation of

Hensley

2009-01-01

93

Nuclear k_T in d+Au Collisions from Multiparticle Jet Reconstruction at STAR  

E-print Network

This paper presents the most recent nuclear k_T measurements from STAR derived from multiparticle jet reconstruction of d+Au and p+p collisions at sqrt(s)=200 GeV. Since jets reconstructed from multiple particles are relatively free of fragmentation biases, nuclear k_T can be measured with greater certainty in this way than with traditional di-hadron correlations. Multi-particle jet reconstruction can also be used for a direct measurement of the fragmentation function.

Thomas Henry

2005-11-01

94

Cryogenic Neutron Spectrometer Development  

SciTech Connect

Cryogenic microcalorimeter detectors operating at temperatures around {approx}0.1 K have been developed for the last two decades, driven mostly by the need for ultra-high energy resolution (<0.1%) in X-ray astrophysics and dark matter searches [1]. The Advanced Detector Group at Lawrence Livermore National Laboratory has developed different cryogenic detector technologies for applications ranging from X-ray astrophysics to nuclear science and non-proliferation. In particular, we have adapted cryogenic detector technologies for ultra-high energy resolution gamma-spectroscopy [2] and, more recently, fast-neutron spectroscopy [3]. Microcalorimeters are essentially ultra-sensitive thermometers that measure the energy of the radiation from the increase in temperature upon absorption. They consist of a sensitive superconducting thermometer operated at the transition between its superconducting and its normal state, where its resistance changes very rapidly with temperature such that even the minute energies deposited by single radiation quanta are sufficient to be detectable with high precision. The energy resolution of microcalorimeters is fundamentally limited by thermal fluctuations to {Delta}E{sub FWHM} {approx} 2.355 (k{sub B}T{sup 2}C{sub abs}){sup 1/2}, and thus allows an energy below 1 keV for neutron spectrometers for an operating temperature of T {approx} 0.1 K . The {Delta}E{sub FWHM} does not depend on the energy of the incident photon or particle. This expression is equivalent to the familiar (F{var_epsilon}E{sub {gamma}}){sup 1/2} considering that an absorber at temperature T contains a total energy C{sub abs}T, and the associated fluctuation are due to variations in uncorrelated (F=1) phonons ({var_epsilon} = k{sub B}T) dominated by the background energy C{sub abs}T >> E{gamma}. The rationale behind developing a cryogenic neutron spectrometer is the very high energy resolution combined with the high efficiency. Additionally, the response function is simple and the instrument is transportable. We are currently developing a fast neutron spectrometer with 0.1% energy resolution at 1 MeV neutron energy with an efficiency of > 1%. Our fast-neutron spectrometers use boron-based and {sup 6}LiF absorber crystals with Mo/Cu thermistors readout. They have achieved an energy resolution of 5.5 keV FWHM for 2.79 MeV deposited in {sup 10}B by thermal neutron capture (fig. 1), and 46 keV FWHM for fast (MeV) neutrons absorbed in {sup 6}LiF (fig. 2). Since the energy resolution does not depend on the neutron energy, we expect a similar energy resolution for MeV neutron energies. The response function is given simply by the cross section of the capture reaction, offset from zero by the Q-value of the capture reaction. This allows straightforward discrimination against gamma-events, most of which deposit less that Q{sub 6Li} = 4.79 MeV in the {sup 6}LiF absorber, and easy deconvolution of the neutron spectrum, since there is only a single capture reaction in {sup 6}Li and the spectrum is not affected by edge effects or geometric broadening. The current challenge for microcalorimeters is their necessarily small effective pixel area, {approx}1cm{sup 3} for neutron spectrometer pixels, and their slow decay time, {approx}10ms for neutron spectrometers. The pixel size is limited by the requirement for low Cabs for high energy resolution; the decay time is set by the intrinsically weak thermal coupling between materials at low temperatures. Both issues can be addressed by fabricating large detector arrays. This will enable high-precision neutron spectrometry with high statistics, such as simulated for Pu analysis in fig 3.

Niedermayr, T; Hau, I D; Friedrich, S; Burger, A; Roy, U N; Bell, Z W

2006-03-08

95

A negative ion source for spectrometer calibration  

Microsoft Academic Search

Summary form only given. A negative ion source has been built to perform the primary calibrations of the electron spectrometers used on the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility at Los Alamos National Laboratory. The calibration requirement for the DARHT electron beam calls for an energy\\/momentum measurement of better than 1% absolute precision, and better than 0.5% relative precision.

R. Trainham; R. R. Bartsch; C. Ekdahl; A. P. Tipton; H. A. Bender

2004-01-01

96

On the Partial-Wave Analysis of Mesonic Resonances Decaying to Multiparticle Final States Produced by Polarized Photons  

SciTech Connect

Meson spectroscopy is going through a revival with the advent of high statistics experiments and new advances in the theoretical predictions. The Constituent Quark Model (CQM) is finally being expanded considering more basic principles of field theory and using discrete calculations of Quantum Chromodynamics (lattice QCD). These new calculations are approaching predictive power for the spectrum of hadronic resonances and decay modes. It will be the task of the new experiments to extract the meson spectrum from the data and compare with those predictions. The goal of this report is to describe one particular technique for extracting resonance information from multiparticle final states. The technique described here, partial wave analysis based on the helicity formalism, has been used at Brookhaven National Laboratory (BNL) using pion beams, and Jefferson Laboratory (Jlab) using photon beams. In particular this report broaden this technique to include production experiments using linearly polarized real photons or quasi-real photons. This article is of a didactical nature. We describe the process of analysis, detailing assumptions and formalisms, and is directed towards people interested in starting partial wave analysis.

Salgado, Carlos W. [Norfolk State University, Norfolk, VA (United States) and Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Weygand, Dennis P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-04-01

97

On the partial-wave analysis of mesonic resonances decaying to multiparticle final states produced by polarized photons  

NASA Astrophysics Data System (ADS)

Meson spectroscopy is going through a revival with the advent of high statistics experiments and new advances in the theoretical predictions. The Constituent Quark Model (CQM) is finally being expanded considering more basic principles of field theory and using discrete calculations of Quantum Chromodynamics (lattice QCD). These new calculations are approaching predictive power for the spectrum of hadronic resonances and decay modes. It will be the task of the new experiments to extract the meson spectrum from the data and compare with those predictions. The goal of this report is to describe one particular technique for extracting resonance information from multiparticle final states. The technique described here, partial wave analysis based on the helicity formalism, has been used at Brookhaven National Laboratory (BNL) using pion beams, and Jefferson Laboratory (JLab) using photon beams. In particular this report broadens this technique to include production experiments using linearly polarized real photons or quasi-real photons. This article is of a didactical nature. We describe the process of analysis, detailing assumptions and formalisms, and is directed towards people interested in starting partial wave analysis.

Salgado, Carlos W.; Weygand, Dennis P.

2014-04-01

98

21 CFR 862.2860 - Mass spectrometer for clinical use.  

Code of Federal Regulations, 2011 CFR

...AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments...spectrometer for clinical use is a device intended to identify inorganic or organic compounds (e.g., lead, mercury,...

2011-04-01

99

21 CFR 862.2860 - Mass spectrometer for clinical use.  

Code of Federal Regulations, 2013 CFR

...AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments...spectrometer for clinical use is a device intended to identify inorganic or organic compounds (e.g., lead, mercury,...

2013-04-01

100

21 CFR 862.2860 - Mass spectrometer for clinical use.  

Code of Federal Regulations, 2014 CFR

...AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments...spectrometer for clinical use is a device intended to identify inorganic or organic compounds (e.g., lead, mercury,...

2014-04-01

101

21 CFR 862.2860 - Mass spectrometer for clinical use.  

Code of Federal Regulations, 2012 CFR

...AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments...spectrometer for clinical use is a device intended to identify inorganic or organic compounds (e.g., lead, mercury,...

2012-04-01

102

High efficiency transfer of quantum information and multiparticle entanglement generation in translation-invariant quantum chains  

Microsoft Academic Search

We demonstrate that a translation-invariant chain of interacting quantum systems can be used for high efficiency transfer of quantum entanglement and the generation of multiparticle entanglement over large distances and between arbitrary sites without the requirement of precise spatial or temporal control. The scheme is largely insensitive to disorder and random coupling strengths in the chain. We discuss harmonic oscillator

Martin B Plenio; Fernando L Semião

2005-01-01

103

Proton structure from multiparticle contribution to elastic pp-scattering at 7 TeV  

E-print Network

Proton structure from multiparticle contribution to elastic pp-scattering at 7 TeV I.M. Dremin Lebedev Physical Institute, Moscow 119991, Russia The parton content of protons gets strong peripheral protons. The very first analyses [1, 2, 3] have lead to extremely interesting conclusions about

Heller, Barbara

104

Controlled collisions for multi-particle entanglement of optically trapped atoms  

Microsoft Academic Search

Entanglement lies at the heart of quantum mechanics, and in recent years has been identified as an essential resource for quantum information processing and computation. The experimentally challenging production of highly entangled multi-particle states is therefore important for investigating both fundamental physics and practical applications. Here we report the creation of highly entangled states of neutral atoms trapped in the

Olaf Mandel; Markus Greiner; Artur Widera; Tim Rom; Theodor W. Hänsch; Immanuel Bloch

2003-01-01

105

Optimization of mass spectrometers using the adaptive particle swarm algorithm.  

PubMed

Optimization of mass spectrometers using the adaptive particle swarm algorithm (APSA) is described along with implementations for ion optical simulations and various time-of-flight (TOF) instruments. The need for in situ self optimization is addressed through discussion of the reflectron TOF mass spectrometer (RTOF) on the European Space Agency mission Rosetta. In addition, a tool for optimization of laboratory mass spectrometers is presented and tested on two different instruments. After the application of APSA optimization, a substantial increase in performance for mass spectrometers that have manually been tuned for several weeks or months is demonstrated. PMID:22124986

Bieler, A; Altwegg, K; Hofer, L; Jäckel, A; Riedo, A; Sémon, T; Wahlström, P; Wurz, P

2011-11-01

106

Performance of the EBIT calorimeter spectrometer  

SciTech Connect

The EBIT calorimeter spectrometer (ECS) is a new high-resolution, broadband x-ray spectrometer that has recently been installed at the Electron Beam Ion Trap Facility (EBIT) at the Lawrence Livermore National Laboratory. The ECS is an entirely new production class spectrometer that replaces the XRS/EBIT spectrometer that has been operating at EBIT since 2000. The ECS utilizes a 32-pixel x-ray calorimeter array from the XRS instrument on the Suzaku x-ray observatory. Eighteen of the pixels are optimized for the 0.1-10 keV band and yield 4.5 eV full width at half maximum energy resolution and 95% quantum efficiency at 6 keV. In addition, the ECS includes 14 detector pixels that are optimized for the high-energy band with a bandpass from 0.5 to over 100 keV with 34 eV resolution and 32% quantum efficiency at 60 keV. The ECS detector array is operated at 50 mK using a five stage cryogenic system that is entirely automated. The instrument takes data continuously for over 65 h with a 2.5 h recycle time. The ECS is a nondispersive, broadband, highly efficient spectrometer that is one of the prime instruments at the EBIT facility. The instrument is used for studies of absolute cross sections, charge exchange recombination, and x-ray emission from nonequilibrium plasmas, among other measurements in our laboratory astrophysics program.

Porter, Frederick Scott; Gygax, John; Kelley, Richard L.; Kilbourne, Caroline A.; King, Jonathan M. [Code 662, NASA/GSFC, Greenbelt, Maryland 20771 (United States); Beiersdorfer, Peter; Brown, Gregory V.; Thorn, Daniel B. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Kahn, Steven M. [Department of Physics, Stanford University, Stanford, California 94305 (United States)

2008-10-15

107

The SLIM spectrometer.  

PubMed

A new spectrometer, here denoted the SLIM (simple, low-power, inexpensive, microcontroller-based) spectrometer, was developed that exploits the small size and low cost of solid-state electronic devices. In this device, light-emitting diodes (LED), single-chip integrated circuit photodetectors, embedded microcontrollers, and batteries replace traditional optoelectronic components, computers, and power supplies. This approach results in complete customizable spectrometers that are considerably less expensive and smaller than traditional instrumentation. The performance of the SLIM spectrometer, configured with a flow cell, was evaluated and compared to that of a commercial spectrophotometer. Thionine was the analyte, and the detection limit was approximately 0.2 microM with a 1.5-mm-path length flow cell. Nonlinearity due to the broad emission profile of the LED light sources is discussed. PMID:12530815

Cantrell, Kevin M; Ingle, James D

2003-01-01

108

Composite Spectrometer Prisms  

NASA Technical Reports Server (NTRS)

Efficient linear dispersive element for spectrometer instruments achieved using several different glasses in multiple-element prism. Good results obtained in both two-and three-element prisms using variety of different glass materials.

Breckinridge, J. B.; Page, N. A.; Rodgers, J. M.

1985-01-01

109

The VIR Spectrometer  

Microsoft Academic Search

The Dawn spectrometer (VIR) is a hyperspectral spectrometer with imaging capability. The design fully accomplishes Dawn’s\\u000a scientific and measurement objectives. Determination of the mineral composition of surface materials in their geologic context\\u000a is a primary Dawn objective. The nature of the solid compounds of the asteroid (silicates, oxides, salts, organics and ices)\\u000a can be identified by visual and infrared spectroscopy

M. C. De Sanctis; A. Coradini; E. Ammannito; G. Filacchione; M. T. Capria; S. Fonte; G. Magni; A. Barbis; A. Bini; M. Dami; I. Ficai-Veltroni; G. Preti

2010-01-01

110

Automated calibration of a flight particle spectrometer  

NASA Technical Reports Server (NTRS)

An automatic calibration system was designed for use in the vacuum facility at the Space Science Laboratory of the Marshall Space Flight Center. That system was developed and used in the intervening winter to calibrate the ion spectrometer that eventually flew in May 1986 aboard the NASA project, CRIT 1. During this summer, it is planned to implement the calibration of both an ion and electron spectrometer of a new design whose basic elements were conceived during the winter of 1985 to 1986. This spectrometer was completed in the summer and successfully mounted in the vacuum tank for calibration. However, the source gate valve malfunctioned, and, at the end of the summer, it still needed a replacement. During the inevitable delays in the experimental research, the numerical model of the Critical Velocity effect was completed and these results were presented.

Torbert, Roy B.

1986-01-01

111

MultiParticle Collision Dynamics: A Particle-Based Mesoscale Simulation Approach to the Hydrodynamics of Complex Fluids  

Microsoft Academic Search

In this review, we describe and analyze a mesoscale simulation method for fluid flow, which was introduced by Malevanets and\\u000a Kapral in 1999, and is now called multi-particle collision dynamics (MPC) or stochastic rotation dynamics (SRD). The method\\u000a consists of alternating streaming and collision steps in an ensemble of point particles. The multi-particle collisions are\\u000a performed by grouping particles in

G. Gompper; T. Ihle; D. M. Kroll; R. G. Winkler

112

ELECTRONICS UPGRADE OF HIGH RESOLUTION MASS SPECTROMETERS  

SciTech Connect

High resolution mass spectrometers are specialized systems that allow researchers to determine the exact mass of samples to four significant digits by using magnetic and electronic sector mass analyzers. Many of the systems in use today at research laboratories and universities were designed and built more than two decades ago. The manufacturers of these systems have abandoned the support for some of the mass spectrometers and parts to power and control them have become scarce or obsolete. The Savannah River National Laboratory has been involved in the upgrade of the electronics and software for these legacy machines. The Electronics Upgrade of High Resolution Mass Spectrometers consists of assembling high-end commercial instrumentation from reputable manufacturers with a minimal amount of customization to replace the electronics for the older systems. By taking advantage of advances in instrumentation, precise magnet control can be achieved using high resolution current sources and continuous feedback from a high resolution hall-effect probe. The custom equipment include a precision voltage divider/summing amplifier chassis, high voltage power supply chassis and a chassis for controlling the voltage emission for the mass spectrometer source tube. The upgrade package is versatile enough to interface with valve control, vacuum and other instrumentation. Instrument communication is via a combination of Ethernet and traditional IEEE-488 GPIB protocols. The system software upgrades include precision control, feedback and spectral waveform analysis tools.

Mcintosh, J; Joe Cordaro, J

2008-03-10

113

Non-contact multi-particle annular patterning and manipulation with ultrasound microbeam  

NASA Astrophysics Data System (ADS)

Multiparticle-trapping offers diverse opportunities and applications in biotechnology. It can be applied to creating various functional materials or organizing reactive particles. In this paper, we demonstrate that it is possible to trap and manipulate multi-particles in an annular pattern with a 24 MHz focused ring-type single element ultrasound transducer. Acoustic ring trap can be useful in undertaking biotropism studies due to an equal-distance condition from the center. Also, this ring trap could serve as a force shield to protect analysis area from other cells. The experimental results showed the capability of the proposed method as a multi-cell manipulator in formatting specific patterns of small cells like sperms.

Lee, Changyang; Seob Jeong, Jong; Youn Hwang, Jae; Lee, Jungwoo; Kirk Shung, K.

2014-06-01

114

Non-contact multi-particle annular patterning and manipulation with ultrasound microbeam.  

PubMed

Multiparticle-trapping offers diverse opportunities and applications in biotechnology. It can be applied to creating various functional materials or organizing reactive particles. In this paper, we demonstrate that it is possible to trap and manipulate multi-particles in an annular pattern with a 24?MHz focused ring-type single element ultrasound transducer. Acoustic ring trap can be useful in undertaking biotropism studies due to an equal-distance condition from the center. Also, this ring trap could serve as a force shield to protect analysis area from other cells. The experimental results showed the capability of the proposed method as a multi-cell manipulator in formatting specific patterns of small cells like sperms. PMID:25114330

Lee, Changyang; Seob Jeong, Jong; Youn Hwang, Jae; Lee, Jungwoo; Kirk Shung, K

2014-06-16

115

Multi-particle systems in $?$-Poincaré inspired by 2+1D gravity  

E-print Network

Inspired by a Chern-Simons description of 2+1D gravity coupled to point particles we propose a new Lagrangian of a multiparticle system living in $\\kappa$-Minkowski/$\\kappa$-Poincar\\'e spacetime. We derive the dynamics of interacting particles with $\\kappa$-momentum space, alternative to the one proposed in the "principle of relative locality" literature. The model that we obtain takes into account of the nonlocal topological interactions between the particles, so that the effective multi-particle action is not a sum of their free actions. In this construction the locality of particle processes is naturally implemented, even for distant observers. In particular a particle process is characterized by a local deformed energy-momentum conservation law. The spacetime transformations are generated by total charges/generators for the composite particle system, and leave unaffected the locality of individual particle processes.

Jerzy Kowalski-Glikman; Giacomo Rosati

2015-04-15

116

Multiparticle-multihole configuration mixing description of nuclear many-body systems  

SciTech Connect

In this work we discuss the multiparticle-multihole configuration mixing method which aims to describe the structure of atomic nuclei. Based on a variational principle it is able to treat in a unified way all types of long-range correlations between nucleons, without introducing symmetry breaking. The formalism is presented along with some preliminary results obtained for a few sd-shell nuclei. In the presented applications, the D1S Gogny force has been used.

Robin, C.; Pillet, N.; Le Bloas, J.; Berger, J.-F. [CEA/DAM/DIF, F-91297 Arpajon (France); Zelevinsky, V. G. [Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-10-15

117

Energy evolution of the large-t elastic scattering and its correlation with multiparticle production  

SciTech Connect

It is emphasized that the collective dynamics associated with color confinement is dominating over a point-like mechanism related to a scattering of the proton constituents at the currently available values of the momentum transferred in proton elastic scattering at the LHC. Deep-elastic scattering and its role in the dissimilation of the absorptive and reflective asymptotic scattering mechanisms are discussed with emphasis on the experimental signatures associated with the multiparticle production processes.

Troshin, S. M. [Institute for High Energy Physics, Protvino, Moscow Region, 142281 (Russian Federation)

2013-04-15

118

The Geostationary Fourier Transform Spectrometer  

NASA Technical Reports Server (NTRS)

The Geostationary Fourier Transform Spectrometer (GeoFTS) is an imaging spectrometer designed for an earth science mission to measure key atmospheric trace gases and process tracers related to climate change and human activity. The GeoFTS instrument is a half meter cube size instrument designed to operate in geostationary orbit as a secondary "hosted" payload on a commercial geostationary satellite mission. The advantage of GEO is the ability to continuously stare at a region of the earth, enabling frequent sampling to capture the diurnal variability of biogenic fluxes and anthropogenic emissions from city to continental scales. The science goal is to obtain a process-based understanding of the carbon cycle from simultaneous high spatial resolution measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and chlorophyll fluorescence (CF) many times per day in the near infrared spectral region to capture their spatial and temporal variations on diurnal, synoptic, seasonal and interannual time scales. The GeoFTS instrument is based on a Michelson interferometer design with a number of advanced features incorporated. Two of the most important advanced features are the focal plane arrays and the optical path difference mechanism. A breadboard GeoFTS instrument has demonstrated functionality for simultaneous measurements in the visible and IR in the laboratory and subsequently in the field at the California Laboratory for Atmospheric Remote Sensing (CLARS) observatory on Mt. Wilson overlooking the Los Angeles basin. A GeoFTS engineering model instrument is being developed which will make simultaneous visible and IR measurements under space flight like environmental conditions (thermal-vacuum at 180 K). This will demonstrate critical instrument capabilities such as optical alignment stability, interferometer modulation efficiency, and high throughput FPA signal processing. This will reduce flight instrument development risk and show that the GeoFTS design is mature and flight ready.

Key, Richard; Sander, Stanley; Eldering, Annmarie; Miller, Charles; Frankenberg, Christian; Natra, Vijay; Rider, David; Blavier, Jean-Francois; Bekker, Dmitriy; Wu, Yen-Hung

2012-01-01

119

Investigating graph isomorphism in cospectral graphs via multiparticle quantum walk in fermionic basis and entanglement entropy  

E-print Network

We investigate the graph isomorphism (GI) in some cospectral networks. Two graph are isomorphic when they are related to each other by a relabeling of the graph vertices. We want to investigate the GI in two scalable (n + 2)-regular graphs G4(n; n + 2) and G5(n; n + 2), analytically by using the multiparticle quantum walk. These two graphs are a pair of non-isomorphic connected cospectral regular graphs for any positive integer n. In order to investigation GI in these two graphs, we rewrite the adjacency matrices of graphs in the antisymmetric fermionic basis and show that they are different for thesepairs of graphs. So the multiparticle quantum walk is able to distinguish pairs of non- isomorph graphs. Also we construct two new graphs T4(n; n + 2) and T5(n; n + 2) and repeat the same process of G4 and G5 to study the GI problem by using multiparticle quantum walk. Then we study GI by using the entanglement entropy. To this aim, we calculate entanglement entropy between two parts of network. In our model the nodes are considered as identical quantum harmonic oscillators. The entanglement entropy between two special parts of G4(n; n+2) and G5(n; n+2) are calculated analytically. It is shown that the entanglement entropy can distinguish pairs of non-isomorphic cospectral graphs too.

M. A. Jafarizadeh; F. Eghbalifam; S. Nami

2014-12-03

120

Benchmarking of multiparticle phase scan and acceptance scan techniques for the Spallation Neutron Source linac  

NASA Astrophysics Data System (ADS)

The importance of accurately setting the RF field amplitude and phase, called the RF set-point is well recognized for a high intensity proton linac such as the Spallation Neutron Source (SNS) linac. Techniques such as phase scan and acceptance scan have been used to determine RF set-points. However, benchmarking study of phase scan and acceptance scan techniques based on experiment was never undertaken before. The benchmarking study demonstrated that the multiparticle phase scan technique based on realistic tracking produces RF set-points consistent with those obtained from the acceptance scan technique. Previous work of phase scan type was based on single-particle tracking and the RF set-point from the single-particle phase scan sometimes did not agree well with either that from the multiparticle phase scan or that from the acceptance scan. The analysis based on multiparticle phase scan showed an accurate agreement between the measurement and simulation even when the beam bunch is rather long (the full-width at half-maximum (FWHM) beam bunch length entering the SNS Drift Tube linac tank 1 is about 27°).

Jeon, Dong-o.

2007-08-01

121

New mass spectrometers for hydrogen isotope analyses  

Microsoft Academic Search

Two advanced mass spectrometers for the accurate analysis of mixtures of the hydrogen isotopes are being evaluated by Du Pont personnel at the Savannah River Laboratory. One is a large double-focusing instrument with a resolution of 2000 at mass 4, an abundance sensitivity of > 100,000 for the HT-Dâ doublet, and a sophisticated electronic control and data collection system. The

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

1981-01-01

122

Mass Spectrometer Simulator  

NSDL National Science Digital Library

From the Colby College Chemistry Department, this tutorial will help visitors understand what happens inside a mass spectrometer. Users are able to select various parts of the instrument to learn and see what happens inside: the vaporization chamber, the ionization chamber, the accelerator plates, the curved chamber, and the detector. Shockwave is required to use the learning activity.

Mundy, Bradford P., 1938-

123

The VIR Spectrometer  

NASA Astrophysics Data System (ADS)

The Dawn spectrometer (VIR) is a hyperspectral spectrometer with imaging capability. The design fully accomplishes Dawn’s scientific and measurement objectives. Determination of the mineral composition of surface materials in their geologic context is a primary Dawn objective. The nature of the solid compounds of the asteroid (silicates, oxides, salts, organics and ices) can be identified by visual and infrared spectroscopy using high spatial resolution imaging to map the heterogeneity of asteroid surfaces and high spectral resolution spectroscopy to determine the composition unambiguously. The VIR Spectrometer—covering the range from the near UV (0.25 ?m) to the near IR (5.0 ?m) and having moderate to high spectral resolution and imaging capabilities—is the appropriate instrument for the determination of the asteroid global and local properties. VIR combines two data channels in one compact instrument. The visible channel covers 0.25-1.05 ?m and the infrared channel covers 1-5.0 ?m. VIR is inherited from the VIRTIS mapping spectrometer (Coradini et al. in Planet. Space Sci. 46:1291-1304, 19989; Reininger et al. in Proc. SPIE 2819:66-77, 1996) on board the ESA Rosetta mission. It will be operated for more than 2 years and spend more than 10 years in space.

de Sanctis, M. C.; Coradini, A.; Ammannito, E.; Filacchione, G.; Capria, M. T.; Fonte, S.; Magni, G.; Barbis, A.; Bini, A.; Dami, M.; Ficai-Veltroni, I.; Preti, G.

2011-12-01

124

Mass spectrometer mixture calibrations  

Microsoft Academic Search

Mass spectrometric analyses of hydrogen isotope mixtures can be difficult to make for a number of reasons. The most difficult problem is the possibility of confronting extremely great and extremely small relative mass differences in the same analysis. Commercial mass spectrometers are now available that can overcome these problems. The analytical capabilities and limitations of these instruments will be discussed.

Hicks

1986-01-01

125

Cyclotrons as mass spectrometers  

SciTech Connect

The principles and design choices for cyclotrons as mass spectrometers are described. They are illustrated by examples of cyclotrons developed by various groups for this purpose. The use of present high energy cyclotrons for mass spectrometry is also described. 28 references, 12 figures.

Clark, D.J.

1984-04-01

126

Dual Beam Spectrometer  

NSDL National Science Digital Library

This Quick Time movie describes the operation of a dual beam spectrometer using an optical wedge to improve the accuracy of the absorbance measurement. The movie includes narration and graphs which explain the technological concepts involved. Running time for the movie is 3 minutes and 55 seconds.

Chasteen, Thomas G.

127

Modular Total Absorption Spectrometer at the HRIBF (ORNL, Oak Ridge)  

NASA Astrophysics Data System (ADS)

The Modular Total Absorption Spectrometer (MTAS) array has been designed, constructed, characterized, and applied to the decay studies of 238U fission products at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. A MTAS commissioning run was performed in January 2012 at the mass separator on-line to the HRIBF Tandem accelerator. Preliminary results of MTAS data confirm known decay patterns of 142Ba and 142La deduced from an earlier study using a total absorption spectrometer technique.

Woli?ska-Cichocka, M.; Rykaczewski, K. P.; Fija?kowska, A.; Karny, M.; Grzywacz, R. K.; Gross, C. J.; Johnson, J. W.; Rasco, B. C.; Zganjar, E. F.

2014-06-01

128

Pulsed Nozzle Fourier Transform Microwave Spectrometer: Advances and Applications  

Microsoft Academic Search

The pulsed nozzle Fourier transform microwave (PNFTMW) spectrometer was developed by Balle and Flygare [A new method for observing the rotational spectra of weak molecular complexes: KrHCl. J. Chem. Phys. 1979, 71 (6), 2723–2724 and 1980, 72 (2), 922–932] in 1979. The design, fabrication, and operation of this spectrometer are complicated and it has largely remained a research laboratory tool

E. Arunan; Sagarika Dev; Pankaj K. Mandal

2004-01-01

129

Data acquisition system for the HHIRF spin spectrometer  

SciTech Connect

The Spin Spectrometer at the Holifield Heavy Ion Research Facility (HHIRF) is a multidetector ..gamma..-ray spectrometer consisting of 72 separate NaI detector elements closely packed in a 4..pi.. geometry. The basic apparatus was constructed at Washington University and has been installed and implemented at the HHIRF at Oak Ridge National Laboratory. The spectrometer was designed especially for the investigation of the mechanisms of heavy-ion induced nuclear reactions and of the structure of nuclei with high angular momentum. The data acquisition system is described. (WHK)

Hensley, D.C.

1981-05-28

130

Design of the Compact Wide Swath Imaging Spectrometer (CWIS)  

NASA Astrophysics Data System (ADS)

The Compact Wide Swath Imaging Spectrometer (CWIS) is a pushbroom imaging spectrometer for the solar reflected spectrum (380-2500 nm) with wide swath (1600 elements), fast optical speed (F/1.8), and high uniformity (>=95%). The CWIS compact Dyson demonstrates a reduction in volume and mass over the equivalent Offner-type instrument. CWIS is currently under development at the Jet Propulsion Laboratory and is intended to address the need for high signal to noise ratio compact imaging spectrometer systems for the visible short wave infrared wavelength range. Optical design, stray light modeling, and current status of the instrument are discussed.

Van Gorp, B.; Mouroulis, P.; Wilson, D. W.; Green, R. O.

2014-09-01

131

Tropospheric and Airborne Emission Spectrometers  

NASA Technical Reports Server (NTRS)

X This paper describes the development of two related instruments, the Tropospheric Emission Spectrometer (TES) and the Airborne Emission Spectrometer (AES). Both instruments are infrared imaging Fourier Transform Spectrometers, used for measuring the state of the lower atmosphere, and in particular the measurement of ozone and ozone sources and sinks.

Glavich, Thomas; Beer, Reinhard

1996-01-01

132

HyTES: Thermal Imaging Spectrometer Development  

NASA Technical Reports Server (NTRS)

The Jet Propulsion Laboratory has developed the Hyperspectral Thermal Emission Spectrometer (HyTES). It is an airborne pushbroom imaging spectrometer based on the Dyson optical configuration. First low altitude test flights are scheduled for later this year. HyTES uses a compact 7.5-12 micrometer m hyperspectral grating spectrometer in combination with a Quantum Well Infrared Photodetector (QWIP) and grating based spectrometer. The Dyson design allows for a very compact and optically fast system (F/1.6). Cooling requirements are minimized due to the single monolithic prism-like grating design. The configuration has the potential to be the optimal science-grade imaging spectroscopy solution for high altitude, lighter-than-air (HAA, LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The QWIP sensor allows for optimum spatial and spectral uniformity and provides adequate responsivity which allows for near 100mK noise equivalent temperature difference (NEDT) operation across the LWIR passband. The QWIP's repeatability and uniformity will be helpful for data integrity since currently an onboard calibrator is not planned. A calibration will be done before and after eight hour flights to gage any inconsistencies. This has been demonstrated with lab testing. Further test results show adequate NEDT, linearity as well as applicable earth science emissivity target results (Silicates, water) measured in direct sunlight.

Johnson, William R.; Hook, Simon J.; Mouroulis, Pantazis; Wilson, Daniel W.; Gunapala, Sarath D.; Realmuto, Vincent; Lamborn, Andy; Paine, Chris; Mumolo, Jason M.; Eng, Bjorn T.

2011-01-01

133

A versatile photoelectron spectrometer for pressures up to 30 mbar  

SciTech Connect

High-pressure photoelectron spectroscopy is a rapidly developing technique with applications in a wide range of fields ranging from fundamental surface science and catalysis to energy materials, environmental science, and biology. At present the majority of the high-pressure photoelectron spectrometers are situated at synchrotron end stations, but recently a small number of laboratory-based setups have also emerged. In this paper we discuss the design and performance of a new laboratory based high pressure photoelectron spectrometer equipped with an Al K? X-ray anode and a hemispherical electron energy analyzer combined with a differentially pumped electrostatic lens. The instrument is demonstrated to be capable of measuring core level spectra at pressures up to 30 mbar. Moreover, valence band spectra of a silver sample as well as a carbon-coated surface (graphene) recorded under a 2 mbar nitrogen atmosphere are presented, demonstrating the versatility of this laboratory-based spectrometer.

Eriksson, Susanna K.; Edström, Kristina; Hagfeldt, Anders [Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20 Uppsala (Sweden); Hahlin, Maria; Rensmo, Håkan; Siegbahn, Hans [Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala (Sweden); Kahk, Juhan Matthias; Villar-Garcia, Ignacio J.; Payne, David J. [Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Webb, Matthew J.; Grennberg, Helena [Department of Chemistry-BMC, Uppsala University, Box 576, 75123 Uppsala (Sweden); Yakimova, Rositza [Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping (Sweden); Edwards, Mårten O. M.; Karlsson, Patrik G.; Backlund, Klas; Åhlund, John, E-mail: john.ahlund@vgscienta.com [VG Scienta AB, Box 15120, 750 15 Uppsala (Sweden)

2014-07-15

134

Miniaturized Ion Mobility Spectrometer  

NASA Technical Reports Server (NTRS)

By utilizing the combination of a unique electronic ion injection control circuit in conjunction with a particularly designed drift cell construction, the instantly disclosed ion mobility spectrometer achieves increased levels of sensitivity, while achieving significant reductions in size and weight. The instant IMS is of a much simpler and easy to manufacture design, rugged and hermetically sealed, capable of operation at high temperatures to at least 250.degree. C., and is uniquely sensitive, particularly to explosive chemicals.

Kaye, William J. (Inventor); Stimac, Robert M. (Inventor)

2015-01-01

135

Galileo Ultraviolet Spectrometer experiment  

NASA Technical Reports Server (NTRS)

The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113-432 nm with a wavelength resolution of 0.7 nm below 190 and 1.3 nm at longer wavelengths. The UVS spatial resolution is 0.4 deg x 0.1 deg for illuminated disk observations and 1 deg x 0.1 deg for limb geometries. The EUVS is a Voyager design objective grating spectrometer, modified to cover the wavelength range from 54 to 128 nm with wavelength resolution 3.5 nm for extended sources and 1.5 nm for point sources and spatial resolution of 0.87 deg x 0.17 deg. The EUVS instrument will follow up on the many Voyager UVS discoveries, particularly the sulfur and oxygen ion emissions in the Io torus and molecular and atomic hydrogen auroral and airglow emissions from Jupiter. The UVS will obtain spectra of emission, absorption, and scattering features in the unexplored, by spacecraft, 170-432 nm wavelength region. The UVS and EUVS instruments will provide a powerful instrument complement to investigate volatile escape and surface composition of the Galilean satellites, the Io plasma torus, micro- and macro-properties of the Jupiter clouds, and the composition structure and evolution of the Jupiter upper atmosphere.

Hord, C. W.; Mcclintock, W. E.; Stewart, A. I. F.; Barth, C. A.; Esposito, L. W.; Thomas, G. E.; Sandel, B. R.; Hunten, D. M.; Broadfoot, A. L.; Shemansky, D. E.

1992-01-01

136

EXTENDING THE USEFUL LIFE OF OLDER MASS SPECTROMETERS  

SciTech Connect

Thermal ionization and gas mass spectrometers are widely used across the Department of Energy (DOE) Complex and contractor laboratories. These instruments support critical missions, where high reliability and low measurement uncertainty are essential. A growing number of these mass spectrometers are significantly older than their original design life. The reality is that manufacturers have declared many of the instrument models obsolete, with direct replacement parts and service no longer available. Some of these obsolete models do not have a next generation, commercially available replacement. Today's budget conscious economy demands for the use of creative funds management. Therefore, the ability to refurbish (or upgrade) these valuable analytical tools and extending their useful life is a cost effective option. The Savannah River Site (SRS) has the proven expertise to breathe new life into older mass spectrometers, at a significant cost savings compared to the purchase and installation of new instruments. A twenty-seven year old Finnigan MAT-261{trademark} Thermal Ionization Mass Spectrometer (TIMS), located at the SRS F/H Area Production Support Laboratory, has been successfully refurbished. Engineers from the Savannah River National Laboratory (SRNL) fabricated and installed the new electronics. These engineers also provide continued instrument maintenance services. With electronic component drawings being DOE Property, other DOE Complex laboratories have the option to extend the life of their aged Mass Spectrometers.

Johnson, S.; Cordaro, J.; Holland, M.; Jones, V.

2010-06-17

137

Broadband ferromagnetic resonance spectrometer  

NASA Astrophysics Data System (ADS)

The continuous wave ferromagnetic resonance (FMR) spectrometer operating in multioctave (0.05-40 GHz) frequency range has been built to investigate the magnetic properties of thin ferromagnetic films in the temperature range of 4-420 K. The spectrometer has two probeheads: one is the X-band microwave reflection cavity used to perform express room temperature measurements and the other is an in-cryostat microstrip line probe to carry out FMR experiments covering the entire frequency range offered by the microwave source. Very uniform and stable magnetic field up to 2.4 T, temperature 4 K-420 K, and continuous frequency scan performed by an HP8722D vector network analyzer provide various modes of operation. Both probe heads are equipped with two-circle high precision goniometers to ensure accurate characterization of magnetic anisotropy and magnetostatic waves spectra recording. Use of the phase sensitive detection, utilized by magnetic field modulation at audio frequency and computer triggering of the network analyzer, enables broadband spectrometer sensitivity to be as high as 1.3×1011 spins/Oe.

Denysenkov, V. P.; Grishin, A. M.

2003-07-01

138

Anamorphic imaging spectrometer  

NASA Astrophysics Data System (ADS)

Deployment of compact hyperspectral imaging sensors on small UAVs has the potential of providing a cost-effective solution for rapid-response target detection and cueing based on time critical spectral information collected at low altitudes. To address this goal, a new compact hyperspectral imaging sensor is being developed with an anamorphic optical system that partially decouples image formation along both the spatial and spectral axes found in conventional push-broom hyperspectral imagers. This design concept benefits from a reduction in complexity over standard highperformance spectrometer optical designs while maintaining excellent aberration control and spatial and spectral distortion characteristics. The anamorphic optical system has the advantage of removing the spectrometer slit focus along the spatial axis and in turn eliminates nearly all aberrations in the front-end optics, regardless of field angle or aperture size. This paper presents results from the first prototype anamorphic imaging spectrometer, which weighs 4 pounds and is designed for operation in the Short Wave InfraRed (SWIR) spectral band over a wavelength range of 1 ?m to 1.7 ?m dictated by the uncooled InGaAs focal plane array used as the detector. The anamorphic system design will be discussed and results from characterization and field measurements will be presented.

Swanson, Rand C.; Moon, Thomas S.; Smith, Casey W.; Kehoe, Michael R.; Brown, Steven W.; Lykke, Keith R.

2008-04-01

139

Expert overseer for mass spectrometer system  

DOEpatents

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)

1991-01-01

140

Multi-particle interaction in a model of the hydrophobic interaction  

NASA Astrophysics Data System (ADS)

The multi-particle potential of mean force between interstitial solute molecules in Ben-Naim's one-dimensional, many-state lattice model is calculated. The solution is a direct extension of an earlier calculation of the two-particle interaction by Kolomeisky and Widom (Faraday Dis. 112 (1999) 81). It is found that the many-particle interaction potential is a sum of pair potentials between neighboring particles only. An exact equation of state, expressing the activity in the temperature and the pressure, is derived. The resulting solubility of a gaseous hydrophobe, which is defined osmotically, is calculated and found to increase considerably with the gas density.

Bedeaux, D.; Koper, G. J. M.; Ispolatov, S.; Widom, B.

2001-03-01

141

Effect of multiparticle correlations on the stability of electron-positron clusters  

SciTech Connect

The total energy of electrically neutral electron-positron clusters with closed shells containing different numbers of pairs has been calculated. The inclusion of multiparticle correlations in the random phase approximation with exchange has allowed the reduction of the energy per pair of particles below the energy per dipositronium molecule. The calculations have revealed the region of the minimum of the total energy per pair of particles at the numbers of pairs in the range of 20 to 40, which assumingly correspond to the most stable electron-positron droplets.

Ipatov, A. N., E-mail: Andrei_ipatov@mail.ru; Ivanov, V. K.; Polozkov, R. G. [St. Petersburg State Polytechnic University (Russian Federation)] [St. Petersburg State Polytechnic University (Russian Federation)

2013-10-15

142

Multiparticle collision dynamics: GPU accelerated particle-based mesoscale hydrodynamic simulations  

NASA Astrophysics Data System (ADS)

The Compute Unified Device Architecture (CUDA) programming language on a graphics processing unit (GPU) is exploited to develop a GPU-based simulation program for the multiparticle collision dynamics (MPC) approach, a particle-based mesoscale hydrodynamic simulation technique. The coarse-grained description of the fluid dynamics in terms of ballistic motion and local stochastic interactions of particles renders MPC inherently highly parallel. We achieve a 1-2 orders of magnitude performance gain over a comparable CPU-core version of the algorithm, depending on the implementation (single threaded or OpenMP). Various aspects of the implementation are discussed in the context of an optimized performance.

Westphal, E.; Singh, S. P.; Huang, C.-C.; Gompper, G.; Winkler, R. G.

2014-02-01

143

{gamma} induced multiparticle emissions of medium mass nuclei at intermediate energies  

SciTech Connect

A comprehensive analysis of multiparticle emissions following photon induced reactions at intermediate energies is provided. Photon induced reaction is described in the energy range of {approx}30-140 MeV with an approach based on the quasideuteron nuclear photoabsorption model followed by the process of competition between light particle evaporation and fission for the excited nucleus. The evaporation-fission process of the compound nucleus is simulated in a Monte-Carlo framework. The study shows almost no fission events for the medium mass nuclei and reproduces the available experimental data of photonuclear reaction cross sections satisfactorily at energies {approx}30-140 MeV.

Mukhopadhyay, Tapan; Basu, D. N. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064 (India)

2009-01-15

144

Multi-particle processes in $?$-Poincaré inspired by 2+1D gravity  

E-print Network

Inspired by a Chern-Simons description of 2+1D gravity coupled to point particles we propose a new Lagrangian of a multiparticle system living in $\\kappa$-Minkowski/$\\kappa$-Poincar\\'e spacetime. We derive the dynamics of interacting particles with $\\kappa$-momentum space, alternative to the one proposed in the "principle of relative locality" literature. In this construction the locality of particle processes is naturally implemented, even for distant observers. In particular each particle process is characterized by a local deformed energy-momentum conservation law. On the other hand, the relation between non-causally-connected events still reflects the effects of deformed kinematics and relativity of locality.

Jerzy Kowalski-Glikman; Giacomo Rosati

2014-12-01

145

Portable gas chromatograph-mass spectrometer  

SciTech Connect

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.

1994-12-31

146

Portable gas chromatograph-mass spectrometer  

DOEpatents

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, Brian D. (Livermore, CA); Eckels, Joel D. (Livermore, CA); Kimmons, James F. (Manteca, CA); Myers, David W. (Livermore, CA)

1996-01-01

147

The transition-edge EBIT microcalorimeter spectrometer  

NASA Astrophysics Data System (ADS)

The Transition-edge EBIT Microcalorimeter Spectrometer (TEMS) is a 1000-pixel array instrument to be delivered to the Electron Beam Ion Trap (EBIT) facility at the Lawrence Livermore National Laboratory (LLNL) in 2015. It will be the first fully operational array of its kind. The TEMS will utilize the unique capabilities of the EBIT to verify and benchmark atomic theory that is critical for the analysis of high-resolution data from microcalorimeter spectrometers aboard the next generation of x-ray observatories. We present spectra from the present instrumentation at EBIT, as well as our latest results with time-division multiplexing using the current iteration of the TEMS focal plane assembly in our test platform at NASA/GSFC.

Betancourt-Martinez, Gabriele L.; Adams, Joseph; Bandler, Simon; Beiersdorfer, Peter; Brown, Gregory; Chervenak, James; Doriese, Randy; Eckart, Megan; Irwin, Kent; Kelley, Richard; Kilbourne, Caroline; Leutenegger, Maurice; Porter, F. S.; Reintsema, Carl; Smith, Stephen; Ullom, Joel

2014-07-01

148

Water Mass Map from Neutron Spectrometer  

NASA Technical Reports Server (NTRS)

December 8, 2003

This map shows the estimated lower limit of the water content of the upper meter of Martian soil. The estimates are derived from the hydrogen abundance measured by the neutron spectrometer component of the gamma ray spectrometer suite on NASA's Mars Odyssey spacecraft.

The highest water-mass fractions, exceeding 30 percent to well over 60 percent, are in the polar regions, beyond about 60 degrees latitude north or south. Farther from the poles, significant concentrations are in the area bound in longitude by minus 10 degrees to 50 degrees and in latitude by 30 degrees south to 40 degrees north, and in an area to the south and west of Olympus Mons (30 degrees to 0 degrees south latitude and minus 135 degrees to 110 degrees longitude).

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for the NASA Office of Space Science in Washington. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Space Systems, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL.

2003-01-01

149

Neutron range spectrometer  

DOEpatents

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.

1988-03-10

150

Mossbauer spectrometer radiation detector  

NASA Technical Reports Server (NTRS)

A Mossbauer spectrometer with high efficiencies in both transmission and backscattering techniques is described. The device contains a sodium iodide crystal for detecting radiation caused by the Mossbauer effect, and two photomultipliers to collect the radiation detected by the crystal. When used in the transmission technique, the sample or scatterer is placed between the incident radiation source and the detector. When used in a backscattering technique, the detector is placed between the incident radiation source and the sample of scatterer such that the incident radiation will pass through a hole in the crystal and strike the sample. Diagrams of the instrument are provided.

Singh, J. J. (inventor)

1973-01-01

151

Calibration of a High Resolution Soft X-ray Spectrometer  

SciTech Connect

A high resolution grating spectrometer (HRGS) with 2400 line/mm variable line spacing grating for the 10-50 {angstrom} wavelength range has been designed for laser-produced plasma experiments at the Lawrence Livermore National Laboratory (LLNL). The spectrometer has a large radius of curvature, R=44.3 m, is operated at a 2{sup o} grazing angle and can record high signal-to-noise spectra when used with a low-noise, cooled, charge-coupled device detector. The instrument can be operated with a 10-25 {micro}m wide slit to achieve the best spectral resolving power on laser plasma sources, approaching 2000, or in slitless mode with a small symmetrical emission source. Results will be presented for the spectral response of the spectrometer cross-calibrated at the LLNL Electron Beam Ion Trap facility using the broadband x-ray energy EBIT Calorimeter Spectrometer (ECS).

Dunn, J; Beiersdorfer, P; Brown, G V; Magee, E W

2010-01-26

152

High Resolution VUV Spectrometer at the INDUS-1 Synchrotron Source  

SciTech Connect

An indigenously developed high-resolution vacuum ultraviolet (VUV) spectrometer has recently been commissioned at the INDUS-1 Synchrotron Source, Indore, India for carrying out spectroscopic research of atomic and molecular gases. The spectrometer uses a 6.65-meter concave grating in off-plane Eagle mounting and a photomultiplier tube (PMT) for recording the intensity profile of various spectral lines. Experimental performance of the spectrometer has been tested using laboratory sources and 1200 grooves/mm and 4800 grooves/mm concave gratings. Wavelength resolutions of 0.08 Aa and 0.01 Aa have been achieved when 1200 grooves/mm and 4800 grooves/mm concave gratings have been mounted successfully in the spectrometer. The instrument has been integrated with the high resolution VUV beamline at INDUS-1 and its performance is being evaluated with synchrotron radiation.

Das, Nimai C.; Shukla, Ram P.; Udupa, Dinesh V.; Sahoo, Naba K.; Bhattacharyya, Dibyendu; Sunanda, K.; Saraswathy, P. [Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai -400 085 (India)

2007-01-19

153

Multi-particle correlations, many particle systems, and entropy in effective field theories  

E-print Network

We discuss the treatment, in an effective field theory, of multi-particle correlations within a "large" system. We show that the act of coarse-graining necessarily introduces violations of unitarity in the evolution of states where the particle number is not defined. For an interacting system, such unitarity violations can cascade from the ultraviolet scale to the infrared in a "short" time. Hence, an effective field theory will be grossly inadequate for describing multi-particle correlations and related observables, even far away from the cut-off scale $\\Lambda$. We furthermore argue that if the system is strongly coupled at $\\Lambda$, than its final state {\\em in the Effective Field Theory} (EFT) will appear as the highest entropy state if only low cumulants and correlations of the EFT degrees of freedom are measured. Heuristically, this can serve as an explanation of how "entropy" is created in a microscopically unitary evolution of a Quantum Field Theory (QFT). We conclude by discussing how these considerations might provide a clue to the apparent thermalization in a hadronic collision even in comparatively small systems, as well as the so-called black hole information paradox; We argue the "paradoxes" are likely to be artifacts of using an effective theory beyond its domain of validity.

Giorgio Torrieri

2013-09-19

154

Portable beta spectrometer/dosimeter  

SciTech Connect

As part of an ongoing program to upgrade health and safety radiation survey instruments, the Los Alamos National Laboratory has developed a portable, battery-operated, computerized beta spectrometer/dosimeter. The instrument will support many different detectors, but the one chosen here is a combination plastic scintillator and NaI crystal. The instrument includes pulse conditioning circuits, 128-channel pulse height analyzer with integral liquid crystal display, and a microcomputer system which calculates dose and dose rate from betas incident on the detector. Instrument operating life is about 8 hours between charges. The instrument will, at the user's option, display a beta spectrum or the accumulated dose in millirad, as well as give the user beta dose rates in millirad per hour. Data accumulated in the instrument can be read out through an RS-232 serial port on the instrument. The entire unit weighs 8 pounds, including internal batteries, and is packaged in a small case 25-cm long, 15-cm wide, and 15-cm high.

Erkkila, B.H.; Waechter, D.A.; Brake, R.J.

1983-01-01

155

Gamma ray spectrometer for ITER  

SciTech Connect

Gamma diagnostics is considered to be primary for the confined ?-particles and runaway electrons measurements on ITER. The gamma spectrometer will be embedded into a neutron dump of the ITER Neutral Particle Analyzer diagnostic complex. It will supplement NPA measurements on the fuel isotope ratio and confined alphas/fast ions. In this paper an update on ITER gamma spectrometer developments is given. A new geometry of the system is described and detailed analysis of expected signals for the spectrometer is presented.

Gin, D.; Chugunov, I.; Shevelev, A.; Khilkevitch, E.; Doinikov, D.; Naidenov, V.; Pasternak, A.; Polunovsky, I. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Polytechnicheskaya 26, St. Petersburg, 194021 (Russian Federation); Kiptily, V. [EURATOM / CCFE Fusion Association, Abingdon, OX14 3DB (United Kingdom)

2014-08-21

156

Gamma ray spectrometer for ITER  

NASA Astrophysics Data System (ADS)

Gamma diagnostics is considered to be primary for the confined ?-particles and runaway electrons measurements on ITER. The gamma spectrometer will be embedded into a neutron dump of the ITER Neutral Particle Analyzer diagnostic complex. It will supplement NPA measurements on the fuel isotope ratio and confined alphas/fast ions. In this paper an update on ITER gamma spectrometer developments is given. A new geometry of the system is described and detailed analysis of expected signals for the spectrometer is presented.

Gin, D.; Chugunov, I.; Shevelev, A.; Khilkevitch, E.; Doinikov, D.; Naidenov, V.; Pasternak, A.; Polunovsky, I.; Kiptily, V.

2014-08-01

157

Resonant ultrasound spectrometer  

DOEpatents

An ultrasound resonant spectrometer determines the resonant frequency spectrum of a rectangular parallelepiped sample of a high dissipation material over an expected resonant response frequency range. A sample holder structure grips corners of the sample between piezoelectric drive and receive transducers. Each transducer is mounted on a membrane for only weakly coupling the transducer to the holder structure and operatively contacts a material effective to remove system resonant responses at the transducer from the expected response range. i.e., either a material such as diamond to move the response frequencies above the range or a damping powder to preclude response within the range. A square-law detector amplifier receives the response signal and retransmits the signal on an isolated shield of connecting cabling to remove cabling capacitive effects. The amplifier also provides a substantially frequency independently voltage divider with the receive transducer. The spectrometer is extremely sensitive to enable low amplitude resonance to be detected for use in calculating the elastic constants of the high dissipation sample.

Migliori, Albert (Santa Fe, NM); Visscher, William M. (Los Alamos, NM); Fisk, Zachary (Santa Fe, NM)

1990-01-01

158

DIRECT TRACE ANALYSIS OF VOLATILE ORGANIC COMPOUNDS IN AIR USING ION TRAP MASS SPECTROMETERS WITH FILTERED NOISE FIELDS  

EPA Science Inventory

Two ion trap mass spectrometers and direct air sampling interfaces are being evaluated in the laboratory for monitoring toxic air pollutants in real time. he mass spectrometers are the large, laboratory-based Finnigan MAT ion trap (ITMS) and the compact, field-deployable Teledyne...

159

Multislit optimized spectrometer: flight-like environment test results  

NASA Astrophysics Data System (ADS)

The NASA ESTO funded Multislit Optimized Spectrometer (MOS) Instrument Incubator Program advances a spatial multiplexing spectrometer for coastal ocean remote sensing from laboratory demonstration to flight-like environment testing. The multiple slit design reduces the required telescope aperture leading to mass and volume reductions over conventional spectrometers when applied to the GEO-CAPE oceans mission. This paper discusses the performance and characterization of the MOS instrument from laboratory and thermal vacuum testing. It also presents the current technology readiness level and possible future applications. Results of an ocean color data product simulation study using flight-like performance data from MOS are also covered. The MOS instrument implementation for GEO-CAPE provides system benefits that may lead to measurable cost savings and reductions in risks while meeting its science objectives.

Good, William S.; Valle, Tim; Davis, Curtiss O.; Tufillaro, Nicholas; Spuhler, Peter; Hardesty, Chuck; Staples, Conor

2014-09-01

160

The Multiparticle Quantum Arnol'd Cat: a test case for the decoherence approach to quantum chaos  

E-print Network

A multi-particle extension of the Arnol'd Cat Hamiltonian system is defined and examined. We propose to compute its Alicki-Fannes quantum dynamical entropy, to validate (or disprove) the validity of the decoherence approach to quantum chaos. A first set of numerical experiments is presented and discussed.

Giorgio Mantica

2010-07-06

161

Spectrometer Observations Near Mawrth Vallis  

NASA Technical Reports Server (NTRS)

This targeted image from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) shows a region of heavily altered rock in Mars' ancient cratered highlands. The featured region is just south of Mawrth Vallis, a channel cut by floodwaters deep into the highlands.

CRISM acquired the image at 1216 UTC (8:16 a.m. EDT) on Oct. 2, 2006, near 25.4 degrees north latitude, 340.7 degrees east longitude. It covers an area about 13 kilometers (8 miles) long and, at the narrowest point, about 9 kilometers (5.6 miles) wide. At the center of the image, the spatial resolution is as good as 35 meters (115 feet) per pixel. The image was taken in 544 colors covering 0.36-3.92 micrometers.

This image includes four renderings of the data, all map-projected. At top left is an approximately true-color representation. At top right is false color showing brightness of the surface at selected infrared wavelengths. In the two bottom views, brightness of the surface at different infrared wavelengths has been compared to laboratory measurements of minerals, and regions that match different minerals have been colored. The bottom left image shows areas high in iron-rich clay, and the bottom right image shows areas high in aluminum-rich clay.

Clay minerals are important to understanding the history of water on Mars because their formation requires that rocks were exposed to liquid water for a long time. Environments where they form include soils, cold springs, and hot springs. There are many clay minerals, and which ones form depends on the composition of the rock, and the temperature, acidity, and salt content of the water. CRISM's sister instrument on the Mars Express spacecraft, OMEGA, has spectrally mapped Mars at lower spatial resolution and found several regions rich in clay minerals. The Mawrth Vallis region, in particular, was found to contain iron-rich clay. CRISM is observing these regions at several tens of times higher spatial resolution, to correlate the minerals with different rock formations and to search for new minerals not resolved by OMEGA.

CRISM has found that the iron-rich clays (lower left image) correspond with a layer of rock that is dark red in the true color view (upper left) and bright gray in the infrared (upper right). In addition, it has found previously undetected exposures of aluminum-rich clay, in a rock unit that is buff-colored in the true color view, and bluish in the infrared. Both types of rocks formed early in Mars' history, about 3.8 billion years ago. The difference in clay mineralogy reveals differences in the environment either over time or over a distance of kilometers. CRISM will be taking many more images of the Mawrth Vallis region to piece together the geologic history of this fascinating area that was once a wet oasis on Mars.

The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad.

CRISM's mission: Find the spectral fingerprints of aqueous and hydrothermal deposits and map the geology, composition and stratigraphy of surface features. The instrument will also watch the seasonal variations in Martian dust and ice aerosols, and water content in surface materials -- leading to new understanding of the climate.

NASA's Jet Propulsion Laboratory, a division of the Califonia Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor and built the spacecraft.

2006-01-01

162

Performance and applications of a spectrometer with micromachined scanning grating  

Microsoft Academic Search

Micro Optical Electro Mechanical Systems (MOEMS) gain more and more importance in technical applications. The combination of optical actuators and micromachined silicon technology arise possibilities to realize equipment in high volumes for reasonable prices, that have formerly been expensive laboratory equipment. This paper reports on the performance and applications of a spectrometer in MOEMS technology. It is based on a

Heinrich Grüger; Alexander Wolter; Tobias Schuster; Harald Schenk; Hubert K. Lakner

2003-01-01

163

A novel dual-detector micro-spectrometer  

Microsoft Academic Search

Infrared analysis is a well-established tool for measuring composition and purity of various materials in industrial-, medical- and environmental applications. Traditional spectrometers, for example Fourier Transform Infrared (FTIR) Instruments are mainly designed for laboratory use and are generally, too large, heavy, costly and delicate to handle for remote applications. With important advances in the miniaturization, ruggedness and cost efficiency we

Thomas Otto; Ray Saupe; Volker Stock; Reinhard Bruch; Bernd Gruska; Thomas Gessner

2005-01-01

164

Calibration Of Airborne Visible/IR Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

Paper describes laboratory spectral and radiometric calibration of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) applied to all AVIRIS science data collected in 1987. Describes instrumentation and procedures used and demonstrates that calibration accuracy achieved exceeds design requirements. Developed for use in remote-sensing studies in such disciplines as botany, geology, hydrology, and oceanography.

Vane, G. A.; Chrien, T. G.; Miller, E. A.; Reimer, J. H.

1990-01-01

165

A practical Hadamard transform spectrometer for astronomical application  

NASA Technical Reports Server (NTRS)

The mathematical properties of Hadamard matrices and their application to spectroscopy are discussed. A comparison is made between Fourier and Hadamard transform encoding in spectrometry. The spectrometer is described and its laboratory performance evaluated. The algorithm and programming of inverse transform are given. A minicomputer is used to recover the spectrum.

Tai, M. H.

1977-01-01

166

Night vision imaging spectrometer (NVIS) calibration and configuration: recent developments  

Microsoft Academic Search

The Night Vision Imaging Spectrometer (NVIS) system has participated in a large variety of hyperspectral data collections for the Department of Defense. A large number of improvements to this system have been undertaken. They include the implementation of a calibration process that utilizes in-flight calibration units (IFCU). Other improvements include the completion and implementation of an updated laboratory wavelength assignments

Christopher G. Simi; Anthony B. Hill; Henry Kling; Christopher LaSota; Jerome A. Zadnik; John Parish; Joe Deaver

2001-01-01

167

Detectors for the JWST Near-Infrared Spectrometer  

NASA Technical Reports Server (NTRS)

The Near-Infrared Spectrometer (NIRSpec) places the most stringent demands upon its detectors of all James Webb Space Telescope (JWST) instruments. We present the scientific rationale for challenging requirements including noise laboratory test results that are informing the design of NIRSpec's detector system and operational concept.

Rauscher, B. J.; Strada, P.; Regan, M. W.; Figer, D. F.; Jakobsen, P.; Moseley, H. S.; Boeker, T.

2004-01-01

168

Developing Tools for Undergraduate Spectroscopy: An Inexpensive Visible Light Spectrometer  

ERIC Educational Resources Information Center

The design and implementation of an inexpensive, high-resolution Littrow-type visible light spectrometer is presented. The instrument is built from low-cost materials and interfaced with the program RSpec for real-time spectral analysis, making it useful for classroom and laboratory exercises. Using a diffraction grating ruled at 1200 lines/mm and…

Vanderveen, Jesse R.; Martin, Brian; Ooms, Kristopher J.

2013-01-01

169

The Portable Remote Imaging Spectrometer (PRISM) Coastal Ocean Sensor  

NASA Technical Reports Server (NTRS)

PRISM is an airborne pushbroom imaging spectrometer intended to address the needs of airborne coastal ocean science research. Its critical characteristics are high throughput and signal-to-noise ratio, high uniformity of response to reduce spectral artifacts, and low polarization sensitivity. We give a brief overview of the instrument and results from laboratory calibration measurements regarding the spatial, spectral, radiometric and polarization characteristics.

Mouroulis, Pantazis; VanGorp, Byron E.; Green, Robert O.; Eastwppd, Michael; Wilson, Daniel W.; Richardson, Brandon; Dierssen, Heidi

2012-01-01

170

Photo ion spectrometer  

DOEpatents

A charged particle spectrometer is described for performing ultrasensitive quantitative analysis of selected atomic components removed from a sample. Significant improvements in performing energy and angular refocusing spectroscopy are accomplished by means of a two dimensional structure for generating predetermined electromagnetic field boundary conditions. Both resonance and non-resonance ionization of selected neutral atomic components allow accumulation of increased chemical information. A multiplexed operation between a SIMS mode and a neutral atomic component ionization mode with EARTOF analysis enables comparison of chemical information from secondary ions and neutral atomic components removed from the sample. An electronic system is described for switching high level signals, such as SIMS signals, directly to a transient recorder and through a charge amplifier to the transient recorder for a low level signal pulse counting mode, such as for a neutral atomic component ionization mode. 12 figs.

Gruen, D.M.; Young, C.E.; Pellin, M.J.

1989-12-26

171

Photo ion spectrometer  

DOEpatents

A charged particle spectrometer for performing ultrasensitive quantitative analysis of selected atomic components removed from a sample. Significant improvements in performing energy and angular refocusing spectroscopy are accomplished by means of a two dimensional structure for generating predetermined electromagnetic field boundary conditions. Both resonance and non-resonance ionization of selected neutral atomic components allow accumulation of increased chemical information. A multiplexed operation between a SIMS mode and a neutral atomic component ionization mode with EARTOF analysis enables comparison of chemical information from secondary ions and neutral atomic components removed from the sample. An electronic system is described for switching high level signals, such as SIMS signals, directly to a transient recorder and through a charge amplifier to the transient recorder for a low level signal pulse counting mode, such as for a neutral atomic component ionization mode.

Gruen, Dieter M. (Downers Grove, IL); Young, Charles E. (Westmont, IL); Pellin, Michael J. (Naperville, IL)

1989-01-01

172

Broadband Liquid Dielectric Spectrometer  

NASA Astrophysics Data System (ADS)

A dielectric spectrometer was built to measure the dielectric relaxation of proteins in solution. The dielectric cell consisted of two parallel stainless-steel electrodes (separation of 8.5 mm) embedded in PTFE. To provide temperature stability, thermally regulated water flowed through both electrodes. The cell was connected to a 4294A Precision Impedance Analyzer, providing impedance measurements from 40Hz to 110 MHz. Due to electrode polarization and high frequency parasitics, useful measurements were obtained for frequencies ranging from 10 kHz to 10 MHz. Calibration was performed using air, iso-propanol and deionized water. Experiments were also conducted on buffers and salt solutions. The dielectric relaxation of the protein beta-lactoglobulin was measured at mg/ml concentrations.

Chandra, Satyan; Arellano, Jesus; Mazzeo, Brian

2009-10-01

173

Imaging Fourier transform spectrometer  

NASA Astrophysics Data System (ADS)

Design considerations and experimental measurements from an imaging Fourier transform spectrometer are presented. The system is based on the Bomem MB-series of Fourier transform interferometer and is capable of more than 8 frames/second at 4 cm(superscript -1 apodized spectral resolution. The interferometer features dual output beams, allowing for example, the coverage of two different spectral ranges using a short-wave array and a long- wave array. The present system uses a set of two 8 X 8 InSb detector arrays to cover the 2 to 5.3 micrometers spectral range on two coaligned fields of view of 4 mrad X 4 mrad and 1 mrad X 1 mrad. Predicted noise equivalent spectral radiance as well as instrument lineshape are compared to measurements on the actual system. Particular emphasis is devoted to the behavior of the instrument lineshape with respect to off-axis position in the focal plane.

Villemaire, Andre J.; Fortin, Serge; Giroux, Jean; Smithson, Tracy; Oermann, Raymond J.

1995-06-01

174

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

2012-10-16

175

Image quality with array spectrometers  

Microsoft Academic Search

We present data on the image quality achieved with the near IR array spectrometer cooled grating spectrometer 4 (CGS4) on the UK IR telescope (UKIRT) on Mauna Kea. A design spot size of 30 micrometers was specified for CGS4, to maintain acceptable image quality with both the 58 by 62 pixel array with which it is currently equipped and the

Suzanne K. Ramsay Howat; Gillian S. Wright; David Montgomery; Eli I. Atad-Ettedgui

1994-01-01

176

ATF beamline 1 analysis spectrometer  

SciTech Connect

We describe the design parameters and expected performance of the analysis spectrometer for beamline 1 at the BNL Accelerator Test Facility. The spectrometer should be well suited for measuring the change in energy caused by the first generation laser acceleration experiments.

Fernow, R.C.; Kirk, H.G.; Ulc, S.

1993-01-01

177

The Geostationary Fourier Transform Spectrometer  

Microsoft Academic Search

The Geostationary Fourier Transform Spectrometer (GeoFTS) is an imaging spectrometer designed for an earth science mission to measure key atmospheric trace gases and process tracers related to climate change and human activity. The GeoFTS instrument is a half meter cube size instrument designed to operate in geostationary orbit as a secondary “hosted” payload on a commercial geostationary satellite mission. The

Richard Key; Stanley Sander; Annmarie Eldering; David Rider; Jean-Francois Blavier; Dmitriy Bekker; Yen-Hung Wu; Ken Manatt

2012-01-01

178

Lunar orbital mass spectrometer experiment  

NASA Technical Reports Server (NTRS)

The design, development, manufacture, test and calibration of five lunar orbital mass spectrometers with the four associated ground support equipment test sets are discussed. A mass spectrometer was installed in the Apollo 15 and one in the Apollo 16 Scientific Instrument Module within the Service Module. The Apollo 15 mass spectrometer was operated with collection of 38 hours of mass spectra data during lunar orbit and 50 hours of data were collected during transearth coast. The Apollo 16 mass spectrometer was operated with collection of 76 hours of mass spectra data during lunar orbit. However, the Apollo 16 mass spectrometer was ejected into lunar orbit upon malfunction of spacecraft boom system just prior to transearth insection and no transearth coast data was possible.

Lord, W. P.

1971-01-01

179

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

SciTech Connect

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)

2011-08-15

180

Preliminary testing of a prototype portable X-ray fluorescence spectrometer  

NASA Technical Reports Server (NTRS)

A portable X-ray fluorescence spectrometer for use as an analyzer in mineral resource investigative work was built and tested. The prototype battery powered spectrometer, measuring 11 by 12 by 5 inches and weighing only about 15 pounds, was designed specifically for field use. The spectrometer has two gas proportional counters and two radioactive sources, Cd (10a) and Fe (55). Preliminary field and laboratory tests on rock specimens and rock pulps have demonstrated the capability of the spectrometer to detect 33 elements to date. Characteristics of the system present some limitations, however, and further improvements are recommended.

Patten, L. L.; Anderson, N. B.; Stevenson, J. J.

1982-01-01

181

A balloon-borne aerosol spectrometer for high altitude low aerosol concentration measurements  

SciTech Connect

Funded by Air Force Wright Aeronautical Laboratory, a new balloon-borne high altitude aerosol spectrometer, for the measurement of cirrus cloud ice crystals, has been developed and successfully flown by Sandia National Laboratories and Radiance Research. This report (1) details the aerosol spectrometer design and construction, (2) discusses data transmission and decoding, (3) presents data collected on three Florida flights in tables and plots. 2 refs., 11 figs., 3 tabs.

Brown, G.S. (Sandia National Labs., Albuquerque, NM (USA)); Weiss, R.E. (Radiance Research, Seattle, WA (USA))

1990-08-01

182

Multi-particle FEM modeling on microscopic behavior of 2D particle compaction  

NASA Astrophysics Data System (ADS)

In this paper, the discrete random packing and various ordered packings such as tetragonal and hexagonal close packed structures generated by discrete element method and honeycomb, which is manually generated were input as the initial packing structures into the multi-particle finite element model (FEM) to study their densification during compaction, where each particle is discretized as a FEM mesh. The macro-property such as relative density and micro-properties such as local morphology, stress, coordination number and densification mechanism obtained from various initial packings are characterized and analyzed. The results show that the coupling of discrete feature in particle scale with the continuous FEM in macro-scale can effectively conquer the difficulties in traditional FEM modeling, which provides a reasonable way to reproduce the compaction process and identify the densification mechanism more accurately and realistically.

Zhang, Y. X.; An, X. Z.; Zhang, Y. L.

2015-03-01

183

Multiparticle quantum Szilard engine with optimal cycles assisted by a Maxwell's demon.  

PubMed

We present a complete-quantum description of a multiparticle Szilard engine that consists of a working substance and a Maxwell's demon. The demon is modeled as a multilevel quantum system with specific quantum control, and the working substance consists of identical particles obeying Bose-Einstein or Fermi-Dirac statistics. In this description, a reversible scheme to erase the demon's memory by a lower-temperature heat bath is used. We demonstrate that (1) the quantum control of the demon can be optimized for a single-particle Szilard engine so that the efficiency of the demon-assisted thermodynamic cycle could reach the Carnot cycle's efficiency and (2) the low-temperature behavior of the working substance is very sensitive to the quantum statistics of the particles and the insertion position of the partition. PMID:22587045

Cai, C Y; Dong, H; Sun, C P

2012-03-01

184

Controlled-NOT for multiparticle qubits and topological quantum computation based on parity measurements  

E-print Network

We discuss a measurement-based implementation of a controlled-NOT (CNOT) quantum gate. Such a gate has recently been discussed for free electron qubits. Here we extend this scheme for qubits encoded in product states of two (or more) spins-1/2 or in equivalent systems. The key to such an extension is to find a feasible qubit-parity meter. We present a general scheme for reducing this qubit-parity meter to a local spin-parity measurement performed on two spins, one from each qubit. Two possible realizations of a multiparticle CNOT gate are further discussed: electron spins in double quantum dots in the singlet-triplet encoding, and nu=5/2 Ising non-Abelian anyons using topological quantum computation braiding operations and nontopological charge measurements.

Oded Zilberberg; Bernd Braunecker; Daniel Loss

2008-01-25

185

Exploring conformational modes of macromolecular assemblies by multi-particle cryo-EM  

PubMed Central

Summary Single particle cryo-electron microscopy (cryo-EM) is a technique aimed at structure determination of large macromolecular complexes in their unconstrained, physiological conditions. The power of the method has been demonstrated in selected studies where for highly symmetric molecules the resolution attained permitted backbone tracing. However, most molecular complexes appear to exhibit intrinsic conformational variability necessary to perform their functions. Therefore, it is now increasingly recognized that sample heterogeneity constitutes a major methodological challenge for cryo-EM. To overcome it dedicated experimental and particularly computational multi-particle approaches have been developed. Their applications point to the future of cryo-EM as an experimental method uniquely suited to visualize the conformational modes of large macromolecular complexes and machines. PMID:19767196

Spahn, Christian M.T.; Penczek, Pawel A.

2009-01-01

186

Searching for low-lying multi-particle thresholds in lattice spectroscopy  

SciTech Connect

We explore the Euclidean-time tails of odd-parity nucleon correlation functions in a search for the S-wave pion–nucleon scattering-state threshold contribution. The analysis is performed using 2+1 flavor 32{sup 3}×64 PACS-CS gauge configurations available via the ILDG. Correlation matrices composed with various levels of fermion source/sink smearing are used to project low-lying states. The consideration of 25,600 fermion propagators reveals the presence of more than one state in what would normally be regarded as an eigenstate-projected correlation function. This observation is in accord with the scenario where the eigenstates contain a strong mixing of single and multi-particle states but only the single particle component has a strong coupling to the interpolating field. Employing a two-exponential fit to the eigenvector-projected correlation function, we are able to confirm the presence of two eigenstates. The lower-lying eigenstate is consistent with a N? scattering threshold and has a relatively small coupling to the three-quark interpolating field. We discuss the impact of this small scattering-state contamination in the eigenvector projected correlation function on previous results presented in the literature. -- Highlights: • Correlation-matrix projected correlators reveal more than one state contributing. • Results are associated with strong mixing of single and multi-particle states in QCD. • A two-exponential fit confirms the presence of two QCD eigenstates. •The lower-lying eigenstate is consistent with a nucleon–pion scattering threshold. •The impact of this small contamination on the higher-lying state is examined.

Mahbub, M. Selim [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia) [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia); CSIRO Computational Informatics, College Road, Sandy Bay, TAS 7005 (Australia); Kamleh, Waseem [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia)] [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia); Leinweber, Derek B., E-mail: derek.leinweber@adelaide.edu.au [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia); Williams, Anthony G. [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia)] [Special Research Centre for the Subatomic Structure of Matter, School of Chemistry and Physics, The University of Adelaide, SA, 5005 (Australia)

2014-03-15

187

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.

1994-06-01

188

VEGAS: VErsatile GBT Astronomical Spectrometer  

NASA Astrophysics Data System (ADS)

The National Science Foundation Advanced Technologies and Instrumentation (NSF-ATI) program is funding a new spectrometer backend for the Green Bank Telescope (GBT). This spectrometer is being built by the CICADA collaboration - collaboration between the National Radio Astronomy Observatory (NRAO) and the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California Berkeley.The backend is named as VErsatile GBT Astronomical Spectrometer (VEGAS) and will replace the capabilities of the existing spectrometers. This backend supports data processing from focal plane array systems. The spectrometer will be capable of processing up to 1.25 GHz bandwidth from 8 dual polarized beams or a bandwidth up to 10 GHz from a dual polarized beam.The spectrometer will be using 8-bit analog to digital converters (ADC), which gives a better dynamic range than existing GBT spectrometers. There will be 8 tunable digital sub-bands within the 1.25 GHz bandwidth, which will enhance the capability of simultaneous observation of multiple spectral transitions. The maximum spectral dump rate to disk will be about 0.5 msec. The vastly enhanced backend capabilities will support several science projects with the GBT. The projects include mapping temperature and density structure of molecular clouds; searches for organic molecules in the interstellar medium; determination of the fundamental constants of our evolving Universe; red-shifted spectral features from galaxies across cosmic time and survey for pulsars in the extreme gravitational environment of the Galactic Center.

Bussa, Srikanth; VEGAS Development Team

2012-01-01

189

Neutron range spectrometer  

DOEpatents

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated 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. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

Manglos, Stephen H. (East Syracuse, NY)

1989-06-06

190

Photo ion spectrometer  

DOEpatents

A method and apparatus for extracting for quantitative analysis ions of selected atomic components of a sample. A lens system is configured to provide a slowly diminishing field region for a volume containing the selected atomic components, enabling accurate energy analysis of ions generated in the slowly diminishing field region. The lens system also enables focusing on a sample of a charged particle beam, such as an ion beam, along a path length perpendicular to the sample and extraction of the charged particles along a path length also perpendicular to the sample. Improvement of signal to noise ratio is achieved by laser excitation of ions to selected autoionization states before carrying out quantitative analysis. Accurate energy analysis of energetic charged particles is assured by using a preselected resistive thick film configuration disposed on an insulator substrate for generating predetermined electric field boundary conditions to achieve for analysis the required electric field potential. The spectrometer also is applicable in the fields of SIMS, ISS and electron spectroscopy.

Gruen, Dieter M. (Downers Grove, IL); Young, Charles E. (Westmont, IL); Pellin, Michael J. (Naperville, IL)

1989-01-01

191

Aerosol mobility size spectrometer  

DOEpatents

A device for measuring aerosol size distribution within a sample containing aerosol particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording aerosol size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an aerosol injection port adjacent the inlet for introducing a charged aerosol sample into the chamber, a separation section for applying an electric field to the aerosol sample across the flow direction and an outlet opposite the inlet. In the separation section, the aerosol sample becomes entrained in the flow medium and the aerosol particles within the aerosol sample are separated by size into a plurality of aerosol flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one aerosol flow stream exiting the outlet and for optically detecting the number of aerosol particles within the at least one aerosol flow stream.

Wang, Jian (Port Jefferson, NY); Kulkarni, Pramod (Port Jefferson Station, NY)

2007-11-20

192

Photo ion spectrometer  

DOEpatents

A method and apparatus are described for extracting for quantitative analysis ions of selected atomic components of a sample. A lens system is configured to provide a slowly diminishing field region for a volume containing the selected atomic components, enabling accurate energy analysis of ions generated in the slowly diminishing field region. The lens system also enables focusing on a sample of a charged particle beam, such as an ion beam, along a path length perpendicular to the sample and extraction of the charged particles along a path length also perpendicular to the sample. Improvement of signal to noise ratio is achieved by laser excitation of ions to selected auto-ionization states before carrying out quantitative analysis. Accurate energy analysis of energetic charged particles is assured by using a preselected resistive thick film configuration disposed on an insulator substrate for generating predetermined electric field boundary conditions to achieve for analysis the required electric field potential. The spectrometer also is applicable in the fields of SIMS, ISS and electron spectroscopy. 8 figs.

Gruen, D.M.; Young, C.E.; Pellin, M.J.

1989-08-08

193

Cascaded interferometric imaging spectrometer  

NASA Astrophysics Data System (ADS)

We present what we believe to be a novel method for order sorting a Fabry-Perot interferometer using a Fourier transform spectrometer (FTS) in tandem. We demonstrate how the order sorting is achieved using a model instrument response as an example of an instrument working in the 5-25 ?m band, although the method is generally applicable at all wavelengths. We show that an instrument of this type can be realized with a large bandwidth, a large field of view, and good transmission efficiency. These attributes make this instrument concept a useful technique in applications where true imaging spectroscopy is required, such as mapping large astronomical sources. We compare the performance of the new instrument to grating and standard FTS instruments in circumstances where the measurement is background and detector noise limited. We use a figure of merit based on the field of view and speed of detection and find that the new system has a speed advantage over a FTS with the same field of view in all circumstances. The instrument will be faster than a grating instrument with the same spectral resolution once the field of view is >13 times larger under high background conditions and >50 times larger with detector performances that match the photon noise from Zodiacal light.

Swinyard, Bruce; Ferlet, Marc

2007-09-01

194

Multiple order common path spectrometer  

NASA Technical Reports Server (NTRS)

The present invention relates to a dispersive spectrometer. The spectrometer allows detection of multiple orders of light on a single focal plane array by splitting the orders spatially using a dichroic assembly. A conventional dispersion mechanism such as a defraction grating disperses the light spectrally. As a result, multiple wavelength orders can be imaged on a single focal plane array of limited spectral extent, doubling (or more) the number of spectral channels as compared to a conventional spectrometer. In addition, this is achieved in a common path device.

Newbury, Amy B. (Inventor)

2010-01-01

195

Method for calibrating mass spectrometers  

DOEpatents

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

2002-12-24

196

Multichannel Fabry-Perot spectrometer for infrared astronomy  

NASA Technical Reports Server (NTRS)

A multichannel design which makes use of the radiation normally rejected in a Fabry-Perot spectrometer is described, with application to infrared astronomy. The present optical design minimizes the diameters of the etalon and optics. The use of spherical mirrors ensures that no radiation is lost through the entrance aperture, and the beams can be completely collimated at the etalon. Laboratory studies demonstrate that the ability to employ eight channels increases by a factor of four the flux integrated during a given time period compared with that of a single-channel instrument. The spectrometer is nondispersive, and the source can be imaged at each of several output spectral positions.

Jennings, Donald E.; Boyle, R. J.

1986-01-01

197

The EBIT Calorimeter Spectrometer: a new, permanent user facility at the LLNL EBIT  

SciTech Connect

The EBIT Calorimeter Spectrometer (ECS) is currently being completed and will be installed at the EBIT facility at the Lawrence Livermore National Laboratory in October 2007. The ECS will replace the smaller XRS/EBIT microcalorimeter spectrometer that has been in almost continuous operation since 2000. The XRS/EBIT was based on a spare laboratory cryostat and an engineering model detector system from the Suzaku/XRS observatory program. The new ECS spectrometer was built to be a low maintenance, high performance implanted silicon microcalorimeter spectrometer with 4 eV resolution at 6 keV, 32 detector channels, 10 {micro}s event timing, and capable of uninterrupted acquisition sessions of over 60 hours at 50 mK. The XRS/EBIT program has been very successful, producing many results on topics such as laboratory astrophysics, atomic physics, nuclear physics, and calibration of the spectrometers for the National Ignition Facility. The ECS spectrometer will continue this work into the future with improved spectral resolution, integration times, and ease-of-use. We designed the ECS instrument with TES detectors in mind by using the same highly successful magnetic shielding as our laboratory TES cryostats. This design will lead to a future TES instrument at the LLNL EBIT. Here we discuss the legacy of the XRS/EBIT program, the performance of the new ECS spectrometer, and plans for a future TES instrument.

Porter, F S; Beiersdorfer, P; Brown, G V; Doriese, W; Gygax, J; Kelley, R L; Kilbourne, C A; King, J; Irwin, K; Reintsema, C; Ullom, J

2007-09-07

198

Micromachined Slits for Imaging Spectrometers  

NASA Technical Reports Server (NTRS)

Slits for imaging spectrometers can now be fabricated to a precision much greater than previously attainable. What makes this possible is a micromachining process that involves the use of microlithographic techniques.

Wilson, Daniel; Kenny, James; White, Victor

2008-01-01

199

Versatile cluster based photoelectron spectrometer  

SciTech Connect

A recently constructed cluster based photoelectron spectrometer is described. This instrumentation is unique in that it enables the kinetic energy analysis of electrons ejected from both anions and neutral clusters. This capability permits the investigation of discrete electronic levels in all charge states (anionic, neutral, and cationic). A laser vaporization plasma reactor cluster source affixed with a sublimation cell is employed to produce a variety of metal clusters, and the resulting cluster distributions are analyzed with time-of-flight mass spectrometry. The corresponding electronic structure is analyzed with a 'magnetic bottle' photoelectron spectrometer. Examples of instrument performance operating in both anion photodetachment and neutral multiphoton ionization (MPI) modes are provided. In the case of neutral MPI, the corresponding product distribution is collected with a Wiley-McLaren [Rev. Sci. Instrum. 26, 1150 (1955)] mass spectrometer mounted perpendicular to the magnetic bottle photoelectron spectrometer.

Knappenberger, K. L. Jr.; Jones, C. E. Jr.; Sobhy, M. A.; Castleman, A. W. Jr. [Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802 and Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2006-12-15

200

The GRAVITY spectrometers: optical qualification  

NASA Astrophysics Data System (ADS)

GRAVITY1 is a 2nd generation Very Large Telescope Interferometer (VLTI) operated in the astronomical K-band. In the Beam Combiner Instrument2 (BCI) four Fiber Couplers3 (FC) will feed the light coming from each telescope into two fibers, a reference channel for the fringe tracking spectrometer4 (FT) and a science channel for the science spectrometer4 (SC). The differential Optical Path Difference (dOPD) between the two channels will be corrected using a novel metrology concept.5 The metrology laser will keep control of the dOPD of the two channels. It is injected into the spectrometers and detected at the telescope level. Piezo-actuated fiber stretchers correct the dOPD accordingly. Fiber-fed Integrated Optics6 (IO) combine coherently the light of all six baselines and feed both spectrometers. Assisted by Infrared Wavefront Sensors7 (IWS) at each Unit Telescope (UT) and correcting the path difference between the channels with an accuracy of up to 5 nm, GRAVITY will push the limits of astrometrical accuracy to the order of 10 ?as and provide phase-referenced interferometric imaging with a resolution of 4 mas. The University of Cologne developed, constructed and tested both spectrometers of the camera system. Both units are designed for the near infrared (1.95 - 2.45 ?m) and are operated in a cryogenic environment. The Fringe Tracker is optimized for highest transmission with fixed spectral resolution (R = 22) realized by a double-prism.8 The Science spectrometer is more diverse and allows to choose from three different spectral resolutions8 (R = [22, 500, 4000]), where the lowest resolution is achieved with a prism and the higher resolutions are realized with grisms. A Wollaston prism in each spectrometer allows for polarimetric splitting of the light. The goal for the spectrometers is to concentrate at least 90% of the ux in 2 × 2 pixel (36 × 36 ?m2) for the Science channel and in 1 pixel (24 × 24 ?m) in the Fringe Tracking channel. In Section 1, we present the arrangement, direction of spectral dispersion and shift of polarization channels for both spectrometers, and the curvature of the spectra in the science spectrometer. In Section 2 we determine the best focus position of the detectors. The overall contrast of images at different positions of the detector stage is computed with the standard deviation of pixel values in the spectra containing region. In Section 3 we analyze high dynamic range images for each spectrometer and resolution obtained at the afore determined best focus positions. We deduce the ensquared energy from the FWHM of Gaussian fits perpendicular to the spectra.

Yazici, Senol; Straubmeier, Christian; Wiest, Michael; Wank, Imke; Fischer, Sebastian; Horrobin, Matthew; Eisenhauer, Frank; Perrin, Guy; Perraut, Karine; Brandner, Wolfgang; Amorim, Antonio; Schöller, Markus; Eckart, Andreas

2014-07-01

201

Coastal Research Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote-sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly.anomaly. Both the visible and infrared subsystems scan in "pushbroom" mode: that is, an aircraft carrying the system moves along a ground track, the system is aimed downward, and image data are acquired in acrosstrack linear arrays of pixels. Both subsystems operate at a frame rate of 30 Hz. The infrared and visible-light optics are adjusted so that both subsystems are aimed at the same moving swath, which has across-track angular width of 15. Data from the infrared and visible imaging subsystems are stored in the same file along with aircraft-position data acquired by a Global Positioning System receiver. The combination of the three sets of data is used to construct infrared and hyperspectral maps of scanned areas shown.

2002-01-01

202

HEAVY ION FUSION SCIENCE VIRTUAL NATIONAL LABORATORY2nd QUARTER 2010 MILESTONE REPORTDevelop the theory connecting pyrometer and streak camera spectrometer data to the material properties of beam heatedtargets and compare to the data  

SciTech Connect

This milestone has been accomplished. We have extended the theory that connects pyrometer and streak spectrometer data to material temperature on several fronts and have compared theory to NDCX-I experiments. For the case of NDCX-I, the data suggests that as the metallic foils are heated they break into droplets (cf. HIFS VNL Milestone Report FY 2009 Q4). Evaporation of the metallic surface will occur, but optical emission should be directly observable from the solid or liquid surface of the foil or from droplets. However, the emissivity of hot material may be changed from the cold material and interference effects will alter the spectrum emitted from small droplets. These effects have been incorporated into a theory of emission from droplets. We have measured emission using streaked spectrometry and together with theory of emission from heated droplets have inferred the temperature of a gold foil heated by the NDCX-I experiment. The intensity measured by the spectrometer is proportional to the emissivity times the blackbody intensity at the temperature of the foil or droplets. Traditionally, a functional form for the emissivity as a function of wavelength (such as a quadratic) is assumed and the three unknown emissivity parameters (for the case of a quadratic) and the temperature are obtained by minimizing the deviations from the fit. In the case of the NDCX-I experiment, two minima were obtained: at 7200 K and 2400 K. The best fit was at 7200 K. However, when the actual measured emissivity of gold was used and when the theoretical corrections for droplet interference effects were made for emission from droplets having radii in the range 0.2 to 2.0 microns, the corrected emissivity was consistent with the 2400 K value, whereas the fit emissivity at 7200 K shows no similarity to the corrected emissivity curves. Further, an estimate of the temperature obtained from beam heating is consistent with the lower value. This exercise proved to be a warning to be skeptical of assuming functional forms when they are unknown, and also represents a first success of the droplet emission theory. The thermal optical emission from a hot metal surface is polarized (for observation angles that are not normal to the surface). By observing the intensity of both polarizations at two or more observation angles the emissivity can be inferred directly, and the temperature at the surface unambiguously determined. Emission from the spolarization (where the E-field is parallel to the surface and normal to the wave vector) is generally less intense than emission from the p-polarization (E-field that is normal to the s-polarization E-field and the wave vector.) The emissivity and temperature may be inferred directly without assuming any specific functional form for the emissivity or resorting to published data tables (which usually do not apply when temperatures reach the WDM regime). We have derived the theory of polarized emission from hot metals, and consider an improved method of temperature determination that takes advantage of polarization measurements, which we call polarization pyrometry. Thus far we have successfully applied the theory to electrically heated metallic filaments, and will apply the theory to beam heated targets when chamber space constraints are removed that will make it feasible to observe the targets at multiple angles. For the case of experiments on NDCX-II, hydrodynamic expansion on a nanosecond timescale that is comparable to the heating time will result in an expanding fluid, with a strong (but finite) density and temperature gradient. Emission will be observed from positions in the foil near the critical density (where the observation photon frequency is equal to the local plasma frequency). By assuming a brightness temperature equal to the local fluid temperature at the critical frequency, a time history of the emission spectrum from an expanding foil can be synthesized from a hydrodynamic simulation of the target. We find that observations from the ultraviolet to the infrared will allow a probing of the target at dif

More, R.M.; Barnard, J. J.; Bieniosek, F.M.; Henestroza, E.; Lidia, S. M.; Ni, P. A.

2010-04-01

203

Coastal Research Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly. Both the visible and infrared subsystems scan in pushbroom mode: that is, an aircraft carrying the system moves along a ground track, the system is aimed downward, and image data are acquired in across-track linear arrays of pixels. Both subsystems operate at a frame rate of 30 Hz. The infrared and visible-light optics are adjusted so that both subsystems are aimed at the same moving swath, which has across-track angular width of 15 . Data from the infrared and visible imaging subsystems are stored in the same file along with aircraft- position data acquired by a Global Positioning System receiver. The combination of the three sets of data is used to construct infrared and hyperspectral maps of scanned areas (see figure). The visible subsystem is based on a grating spectrograph and a rapid-readout charge-coupled-device camera. Images of the swatch are acquired in 256 spectral bands at wavelengths from 400 to 800 nm. The infrared subsystem, which is sensitive in a single wavelength band of 8 to 10 m, is based on a focal-plane array of HgCdTe photodetectors that are cooled to an operating temperature of 77 K by use of a closed-Stirling-cycle mechanical cooler. The nonuniformities of the HgCdTe photodetector array are small enough that the raw pixel data from the infrared subsystem can be used to recognize temperature differences on the order of 1 C. By use of a built-in blackbody calibration source that can be switched into the field of view, one can obtain bias and gain offset terms for individual pixels, making it possible to offset the effects of nonuniformities sufficiently to enable the measurement of temperature differences as small as 0.1 C.

Lucey, Paul G.; Williams, Timothy; Horton, Keith A.

2004-01-01

204

Preliminary Results of an On-Line, Multi-Spectrometer Fission Product Monitoring System to Support Advanced Gas Reactor Fuel Testing and Qualification in the Advanced Test Reactor at the Idaho National Laboratory  

SciTech Connect

The Advanced Gas Reactor -1 (AGR-1) experiment is the first experiment in a series of eight separate low enriched uranium (LEU) oxycarbide (UCO) tri-isotropic (TRISO) particle fuel (in compact form) experiments scheduled for placement in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The experiment began irradiation in the ATR with a cycle that reached full power on December 26, 2006 and will continue irradiation for about 2.5 years. During this time six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The goals of the irradiation experiment is to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. This paper presents the preliminary test details of the fuel performance, as measured by the control and acquisition software.

Dawn M. Scates; John K. Hartwell; John B. Walter; Mark W. Drigert

2007-10-01

205

Improved Cloud Condensation Nucleus Spectrometer  

NASA Technical Reports Server (NTRS)

An improved thermal-gradient cloud condensation nucleus spectrometer (CCNS) has been designed to provide several enhancements over prior thermal- gradient counters, including fast response and high-sensitivity detection covering a wide range of supersaturations. CCNSs are used in laboratory research on the relationships among aerosols, supersaturation of air, and the formation of clouds. The operational characteristics of prior counters are such that it takes long times to determine aerosol critical supersaturations. Hence, there is a need for a CCNS capable of rapid scanning through a wide range of supersaturations. The present improved CCNS satisfies this need. The improved thermal-gradient CCNS (see Figure 1) incorporates the following notable features: a) The main chamber is bounded on the top and bottom by parallel thick copper plates, which are joined by a thermally conductive vertical wall on one side and a thermally nonconductive wall on the opposite side. b) To establish a temperature gradient needed to establish a supersaturation gradient, water at two different regulated temperatures is pumped through tubes along the edges of the copper plates at the thermally-nonconductive-wall side. Figure 2 presents an example of temperature and supersaturation gradients for one combination of regulated temperatures at the thermally-nonconductive-wall edges of the copper plates. c) To enable measurement of the temperature gradient, ten thermocouples are cemented to the external surfaces of the copper plates (five on the top plate and five on the bottom plate), spaced at equal intervals along the width axis of the main chamber near the outlet end. d) Pieces of filter paper or cotton felt are cemented onto the interior surfaces of the copper plates and, prior to each experimental run, are saturated with water to establish a supersaturation field inside the main chamber. e) A flow of monodisperse aerosol and a dilution flow of humid air are introduced into the main chamber at the inlet end. The inlet assembly is designed to offer improved (relative to prior such assemblies) laminar-flow performance within the main chamber. Dry aerosols are subjected to activation and growth in the supersaturation field. f) After aerosol activation, at the outlet end of the main chamber, a polished stainless-steel probe is used to sample droplets into a laser particle counter. The probe features an improved design for efficient sampling. The counter has six channels with size bins in the range of 0.5- to 5.0-micron diameter. g) To enable efficient sampling, the probe is scanned along the width axis of the main chamber (thereby effecting scanning along the temperature gradient and thereby, further, effecting scanning along the supersaturation gradient) by means of a computer-controlled translation stage.

Leu, Ming-Taun

2010-01-01

206

A pair spectrometer for nuclear astrophysics experiments  

NASA Astrophysics Data System (ADS)

Non-radiative transitions in nuclear capture reactions between light nuclei play a relevant role in stellar nuclear astrophysics, where nuclear processes occur at typical energies from tens to hundreds of keV. At higher energies, instead, the E0 contributions may be shadowed by more intense transitions. The experimental study of E0 transitions requires a specific detection setup, able to uniquely identify events where an electron-positron pair is produced. A compact ?E- E charged-particle spectrometer based on two silicon detectors has been designed to be installed in the jet gas target chamber of the recoil mass separator ERNA (European Recoil separator for Nuclear Astrophysics) at the CIRCE laboratory of Caserta, Italy. The detector design, its performances and the first foreseen applications are described.

Guerro, L.; Di Leva, A.; Gialanella, L.; Saltarelli, A.; Schürmann, D.; Tabassam, U.; Busso, M.; De Cesare, N.; D'Onofrio, A.; Romoli, M.; Terrasi, F.

2014-11-01

207

Simulation of bent crystal spectrometers  

SciTech Connect

In crystal spectrometers one traditionally labels each position in the dispersion/recording plane by a single wavelength value. A simple examination of the crystal spectrometers shows that different areas of the crystal contribute different wavelengths at the same position in the recording plane. Using collimators and apertures one may reduce these effects, as well as reduce the collected signal. Convolving the system response, in that case, may not allow simple analytic estimates of the sensitivity/responsivity of the system. A Monte-Carlo ray-trace program was written in order to study and simulate the real geometry including finite source size effects. The results of using the code will be presented, demonstrating the contributions to the resolution and absolute responsivity, for a particular parabolically bent crystal spectrometer.

Kyrala, G.A.

1984-01-01

208

Mobile spectrometer measures radar backscatter  

NASA Technical Reports Server (NTRS)

The present article is concerned with a helicopter-borne spectrometer (Heloscat), which has been developed to permit high-quality scattering measurements from a mobile platform at remote sites. The term 'spectrometer' referes to a class of scatterometers. The term 'scatterometer' is employed to denote a specialized radar for measuring scattering coefficients as a function of angle. A spectrometer, on the other hand, is a scatterometer which can measure backscatter at several frequencies. The Heloscat system is discussed, taking into account two antennas, RF hardware, and an externally mounted pendulum for angle encoding. A dual-antenna configuration is used for cross-polarized measurements, while a single-antenna system is used for like-polarized measurements. Attention is also given to oscillator characteristics, efficient data handling, and aspects of calibration.

Gogineni, S.; Moore, R. K.; Onstott, R. G.; Kim, Y. S.; Bushnell, D.

1984-01-01

209

Mini ion trap mass spectrometer  

DOEpatents

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.

1995-09-19

210

Mini ion trap mass spectrometer  

DOEpatents

An ion trap 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.

Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

1995-01-01

211

Measuring Breath Alcohol Concentrations with an FTIR Spectrometer  

NASA Astrophysics Data System (ADS)

An FTIR spectrometer equipped with a long-path gas cell can be used to measure breath alcohol concentrations in an instrumental analysis laboratory course. Students use aqueous ethanol solutions to make a calibration curve that relates absorbance signals of breath samples with blood alcohol concentrations. Students use their calibration curve to determine the time needed for their calculated blood alcohol levels to drop below the legal limit following use of a commercial mouthwash. They also calculate their blood alcohol levels immediately after chewing bread. The main goal of the experiment is to provide the students with an interesting laboratory exercise that teaches them about infrared spectrometers. While the results are meant to be only semiquantitative, they have compared well with results from other published studies. A reference is included that describes how to fabricate a long-path gas cell.

Kneisel, Adam; Bellamy, Michael K.

2003-12-01

212

Miniature Time-of-Flight Mass Spectrometer  

NASA Technical Reports Server (NTRS)

Major advances must occur to protect astronauts from prolonged periods in near-zero gravity and high radiation associated with extended space travel. The dangers of living in space must be thoroughly understood and methods developed to reverse those effects that cannot be avoided. Six of the seven research teams established by the National Space Biomedical Research Institute (NSBRI) are studying biomedical factors for prolonged space travel to deliver effective countermeasures. To develop effective countermeasures, each of these teams require identification of and quantitation of complex pharmacological, hormonal, and growth factor compounds (biomarkers) in humans and in experimental animals to develop an in-depth knowledge of the physiological changes associated with space travel. At present, identification of each biomarker requires a separate protocol. Many of these procedures are complicated and the identification of each biomarker requires a separate protocol and associated laboratory equipment. To carry all of this equipment and chemicals on a spacecraft would require a complex clinical laboratory; and it would occupy much of the astronauts time. What is needed is a small, efficient, broadband medical diagnostic instrument to rapidly identify important biomarkers for human space exploration. The Miniature Time-Of- Flight Mass Spectrometer Project in the Technology Development Team is developing a small, high resolution, time-of-flight mass spectrometer (TOFMS) to quantitatively measure biomarkers for human space exploration. Virtues of the JHU/APL TOFMS technologies reside in the promise for a small (less than one cubic ft), lightweight (less than 5 kg), low-power (less than 50 watts), rugged device that can be used continuously with advanced signal processing diagnostics. To date, the JHU/APL program has demonstrated mass capability from under 100 to beyond 10,000 atomic mass units (amu) in a very small, low power prototype for biological analysis. Further, the electronic nature of the TOFMS output makes it ideal for rapid telemetry to earth for in-depth analysis by ground support teams.

Potember, Richard S.

1999-01-01

213

Characterization of the Basalt of Broken Tank, NM for the 'in situ' Calibration Target for the Alpha-Particle X-ray Spectrometer (APXS) on the Upcoming Mars Science Laboratory (MSL) Rover  

NASA Astrophysics Data System (ADS)

The MSL rover mission will launch in Fall 2009. It is equipped with an APXS for analyzing the bulk chemistry of rocks and soils. To monitor the APXS performance in situ on the martian surface over the extended mission, a calibration target will be included on the MSL rover. Engineering constraints led to a 4.2 cm diameter, 3 mm thick, homogeneous rock disc that would survive vibrations during launch. The basalt from Broken Tank, NM was chosen for the flight disc from ~200 volcanic rocks. The basalt is relatively homogeneous, fine- and even-grained, vesicle-free, and extremely dense and hard due to its ophitic texture. Other volcanic rocks - even well characterized samples of BCR - were ruled out due to vesicles, or high contents of glass, phenocrysts, secondary minerals, or fractures. The flight disc was prepared by hand- polishing to a 0.05 micron finish. We obtained scanning electron microscope back-scattered electron maps and X-ray maps (Al, Mg, Ca, Fe, Ti, Na, and K) on the polished, uncoated surface of the target. One pit (~0.03 mm2) and three tiny surface imperfections (<0.04 mm2) were observed on the surface. Electron microprobe analyses on two C-coated thin sections give the following compositions: olivine cores Fa23Fo77 and rims Fa40Fo60; plagioclase cores Ab42An56Or2 and discrete rims Ab62An7Or31; oxides Ilm67Hm33 and also trace chromite, apatite, chlorite, clays and devitrified glass. The NIH software Scion Image was used to determine the modal abundance of each phase in the basalt disk and in two thin sections. Bulk composition was established with multiple XRF laboratory analyses. There is no significant heterogeneity on the scale of the APXS analysis (~1.5 cm). Sulfides were not observed and XRF verified low Ni (<90 ppm) and S (70 ppm), making these elements ideal to monitor any Martian dust build-up during the surface operation. The rock slab is glued into a Ni frame, mounted vertically and accessible with a brush tool. The K- and L- X-ray lines of Ni can be used to monitor the energy efficiency of the X-ray detector. This work was supported by the Space Science Enhancement Program of the Canadian Space Agency and the New Mexico Space Grant Consortium.

Burkemper, L.; King, P. L.; Gellert, R.; Spilde, M. N.; Chamberlin, R. M.

2008-12-01

214

The GRAVITY spectrometers: thermal behaviour  

NASA Astrophysics Data System (ADS)

GRAVITY is a 2nd generation VLTI Instrument o which operates on 6 interferometric baselines by using all 4 Unit Telescopes. It will deliver narrow angle astrometry with 10?as accuracy at the infrared K-band. At the 1. Physikalische Institut of the University of Cologne, which is part of the international GRAVITY consortium, two spectrometers, one for the sciene object, and one for the fringe tracking object, have been designed, manufactured and tested. These spectrometers are two individual devices, each with own housing and interfaces. For a minimized thermal background, the spectrometers are actively cooled down to an operating temperature of 80K in the ambient temperature environment of the Beam Combiner Instrument (BCI) cryostat. The outer casings are mounted thermal isolated to the base plate by glass fiber reinforced plastic (GRP) stands, copper cooling structures conduct the cold inside the spectrometers where it is routed to components via Cu cooling stripes. The spectrometers are covered with shells made of multi insulation foil. There will be shown and compared 3 cooling installations: setups in the Cologne test dewar, in the BCI dewar and in a mock-up cad model. There are some striking differences between the setup in the 2 different dewars. In the Cologne Test dewar the spectrometers are connected to the coldplate (80K); a Cu cooling structure and the thermal isolating GRP stands are bolted to the coldplate. In the BCI dewer Cu cooling structure is connected to the bottom of the nitrogen tank (80K), the GRP stands are bolted to the base plate (240K). The period of time during the cooldown process will be analyzed.

Wank, Imke; Straubmeier, Christian; Wiest, Michael; Yazici, Senol; Fischer, Sebastian; Eisenhauer, Frank; Perrin, Guy S.; Perraut, Karine; Brandner, Wolfgang; Amorim, Antonio; Schöller, Markus; Eckart, Andreas

2014-07-01

215

Force calculation on walls and embedded particles in multiparticle collision dynamics simulations  

E-print Network

Colloidal solutions posses a wide range of time and length scales, so that it is unfeasible to keep track of all of them within a single simulation. As a consequence some form of coarse-graining must be applied. In this work we use the Multi-Particle Collision Dynamics scheme. We describe a particular implementation of no-slip boundary conditions upon a solid surface, capable of providing correct force s on the solid bypassing the calculation of the velocity profile or the stre ss tensor in the fluid near the surface. As an application we measure the friction on a spherical particle, when it is placed in a bulk fluid and when it is confined in a slit. We show that the implementation of the no-slip boundary conditions leads to an enhanced Ensko g friction, which can be understood analytically. Because of the long-range nature of hydrodynamic interactions, the Stokes friction obtained from the simulations is sensitive of the simulation box size. We address this topic for the slit geometry, showing that that the dependence on the system size differs very much from what is expected in a 3D system, where periodic boundary conditions are used in all directions.

A. Imperio; J. T. Padding; W. J. Briels

2011-02-14

216

Start-to-end Transport Design and Multi-particle Tracking for the ILC Electron Source  

SciTech Connect

A train of 2-ns micro bunches of longitudinally polarized electrons are generated in a 120-kV DC-gun based injector in the ILC electron source; a bunching system with extremely high bunching efficiency to compress the micro-bunch down to 20 ps FWHM is designed. Complete optics to transport the electron bunch to the entrance of the 5-GeV damping ring injection line is developed. Start-to-end multi-particle tracking through the beamline is performed including the bunching system, pre-acceleration, chicane, 5-GeV superconducting booster linac, spin rotators and energy compressor. It shows that 94% of the electrons from the DC-gun are captured within the damping ring 6-D acceptance--A{sub x} + A{sub y} {le} 0.09 m and {Delta}E x {Delta}z {le} ({+-} 25 MeV) x ({+-} 3.46 cm)--at the entrance of the damping ring injection line. The field and alignment errors and orbit correction are analyzed.

Zhou, F.; Batygin, Y.; Brachman, A.; Clendenin, J.; Miller, R.H.; Sheppard, J.C.; Woodley, M.D.; /SLAC

2007-02-02

217

Modeling the locomotion of the African trypanosome using multi-particle collision dynamics  

NASA Astrophysics Data System (ADS)

The African trypanosome is a single flagellated micro-organism that causes the deadly sleeping sickness in humans and animals. We study the locomotion of a model trypanosome by modeling the spindle-shaped cell body using an elastic network of vertices with additional bending rigidity. The flagellum firmly attached to the model cell body is either straight or helical. A bending wave propagates along the flagellum and pushes the trypanosome forward in its viscous environment, which we simulate with the method of multi-particle collision dynamics. The relaxation dynamics of the model cell body due to a static bending wave reveals the sperm number from elastohydrodynamics as the relevant parameter. Characteristic cell body conformations for the helically attached flagellum resemble experimental observations. We show that the swimming velocity scales as the root of the angular frequency of the bending wave reminiscent of predictions for an actuated slender rod attached to a large viscous load. The swimming velocity for one geometry collapses on a single master curve when plotted versus the sperm number. The helically attached flagellum leads to a helical swimming path and a rotation of the model trypanosome about its long axis as observed in experiments. The simulated swimming velocity agrees with the experimental value.

Babu, Sujin B.; Stark, Holger

2012-08-01

218

Interfacing an aspiration ion mobility spectrometer to a triple quadrupole mass spectrometer  

NASA Astrophysics Data System (ADS)

This article presents the combination of an aspiration-type ion mobility spectrometer with a mass spectrometer. The interface between the aspiration ion mobility spectrometer and the mass spectrometer was designed to allow for quick mounting of the aspiration ion mobility spectrometer onto a Sciex API-300 triple quadrupole mass spectrometer. The developed instrumentation is used for gathering fundamental information on aspiration ion mobility spectrometry. Performance of the instrument is demonstrated using 2,6-di-tert-butyl pyridine and dimethyl methylphosphonate.

Adamov, Alexey; Viidanoja, Jyrki; Kärpänoja, Esko; Paakkanen, Heikki; Ketola, Raimo A.; Kostiainen, Risto; Sysoev, Alexey; Kotiaho, Tapio

2007-04-01

219

Interfacing an aspiration ion mobility spectrometer to a triple quadrupole mass spectrometer  

SciTech Connect

This article presents the combination of an aspiration-type ion mobility spectrometer with a mass spectrometer. The interface between the aspiration ion mobility spectrometer and the mass spectrometer was designed to allow for quick mounting of the aspiration ion mobility spectrometer onto a Sciex API-300 triple quadrupole mass spectrometer. The developed instrumentation is used for gathering fundamental information on aspiration ion mobility spectrometry. Performance of the instrument is demonstrated using 2,6-di-tert-butyl pyridine and dimethyl methylphosphonate.

Adamov, Alexey; Viidanoja, Jyrki; Kaerpaenoja, Esko; Paakkanen, Heikki; Ketola, Raimo A.; Kostiainen, Risto; Sysoev, Alexey; Kotiaho, Tapio [Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 University of Helsinki (Finland); Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 (Finland) and Moscow Engineering Physics Institute, State University, Kashirskoe shosse 31, 115409, Moscow (Russian Federation); Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 University of Helsinki (Finland); Environics Ltd., Graanintie 5, P.O. Box 349, FI-50101, Mikkeli (Finland); Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 University of Helsinki (Finland) and Drug Discovery and Development Technology Center, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 (Finland); Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 (Finland); Moscow Engineering Physics Institute, State University, Kashirskoe shosse 31, 115409, Moscow (Russian Federation); Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 (Finland) and Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 (Finland)

2007-04-15

220

A cometary ion mass spectrometer  

NASA Technical Reports Server (NTRS)

The development of flight suitable analyzer units for that part of the GIOTTO Ion Mass Spectrometer (IMS) experiment designated the High Energy Range Spectrometer (HERS) is discussed. Topics covered include: design of the total ion-optical system for the HERS analyzer; the preparation of the design of analyzing magnet; the evaluation of microchannel plate detectors and associated two-dimensional anode arrays; and the fabrication and evaluation of two flight-suitable units of the complete ion-optical analyzer system including two-dimensional imaging detectors and associated image encoding electronics.

Shelley, E. G.; Simpson, D. A.

1984-01-01

221

Noble gas abundance and isotope ratios in the atmosphere of Jupiter from the Galileo Probe Mass Spectrometer  

Microsoft Academic Search

The Galileo Probe Mass Spectrometer provided the first data on the noble gas mixing and isotope ratios in the Jovian atmosphere. These measurements and the comparison with solar values constrain models of Jupiter's formation. Significant refinements to the initially reported abundances of argon, krypton, and xenon have been enabled through post-encounter laboratory calibrations using a refurbished engineering unit mass spectrometer

P. R. Mahaffy; H. B. Niemann; A. Alpert; S. K. Atreya; J. Demick; T. M. Donahue; D. N. Harpold; T. C. Owen

2000-01-01

222

High spin nuclear structure studies using the spin spectrometer  

Microsoft Academic Search

The gamma-gamma correlation technique is used to generate two-dimensional histograms of gamma ray energy from gamma-gamma coincidence data. The spin spectrometer at Oak Ridge National Laboratory is used to study the continuum gamma-rays from the reaction ¹°°Mo + ³⁴S at 144 MeV beam energy. Double and triple correlation spectra for transitions in rotational bands are obtained which exhibit characteristic valleys.

1986-01-01

223

Airborne Visible / Infrared Imaging Spectrometer AVIS: Design, Characterization and Calibration  

PubMed Central

The Airborne Visible / Infrared imaging Spectrometer AVIS is a hyperspectral imager designed for environmental monitoring purposes. The sensor, which was constructed entirely from commercially available components, has been successfully deployed during several experiments between 1999 and 2007. We describe the instrument design and present the results of laboratory characterization and calibration of the system's second generation, AVIS-2, which is currently being operated. The processing of the data is described and examples of remote sensing reflectance data are presented.

Oppelt, Natascha; Mauser, Wolfram

2007-01-01

224

An Advanced Neutron Spectrometer for Future Manned Exploration Missions  

NASA Technical Reports Server (NTRS)

An Advanced Neutron Spectrometer (ANS) is being developed to support future manned exploration missions. This new instrument uses a refined gate and capture technique that significantly improves the identification of neutrons in mixed radiation fields found in spacecraft, habitats and on planetary surfaces. The new instrument is a composite scintillator comprised of PVT loaded with litium-6 glass scintillators. We will describe the detection concept and show preliminary results from laboratory tests and exposures at particle accelerators

Christl, Mark; Apple, Jeffrey A.; Cox, Mark D.; Dietz, Kurtis L.; Dobson, Christopher C.; Gibson, Brian F.; Howard, David E.; Jackson, Amanda C.; Kayatin, Mathew J.; Kuznetsov, Evgeny N.; Norwood, Joseph K.; Merril, Garrick W.; Watts, John W.; Sabra, Mohammad S.; Smith, Dennis A.; Rodriquez-Otero, Miguel A.

2014-01-01

225

Imaging IR spectrometer, phase 2  

NASA Technical Reports Server (NTRS)

The development is examined of a prototype multi-channel infrared imaging spectrometer. The design, construction and preliminary performance is described. This instrument is intended for use with JPL Table Mountain telescope as well as the 88 inch UH telescope on Mauna Kea. The instrument is capable of sampling simultaneously the spectral region of 0.9 to 2.6 um at an average spectral resolution of 1 percent using a cooled (77 K) optical bench, a concave holographic grating and a special order sorting filter to allow the acquisition of the full spectral range on a 128 x 128 HgCdTe infrared detector array. The field of view of the spectrometer is 0.5 arcsec/pixel in mapping mode and designed to be 5 arcsec/pixel in spot mode. The innovative optical design has resulted in a small, transportable spectrometer, capable of remote operation. Commercial applications of this spectrometer design include remote sensing from both space and aircraft platforms as well as groundbased astronomical observations.

Gradie, Jonathan; Lewis, Ralph; Lundeen, Thomas; Wang, Shu-I

1990-01-01

226

MICE Spectrometer Magnet System Progress  

SciTech Connect

The first magnets for the muon ionization cooling experimentwill be the tracker solenoids that form the ends of the MICE coolingchannel. The primary purpose of the tracker solenoids is to provide auniform 4 T field (to better than +-0.3 percent over a volume that is 1meter long and 0.3 meters in diameter) spectrometer magnet field for thescintillating fiber detectors that are used to analyze the muons in thechannel before and after ionization cooling. A secondary purpose for thetracker magnet is the matching of the muon beam between the rest of theMICE cooling channel and the uniform field spectrometer magnet. Thetracker solenoid is powered by three 300 amp power supplies. Additionaltuning of the spectrometer is provided by a pair of 50 amp power suppliesacross the spectrometer magnet end coils. The tracker magnet will becooled using a pair of 4 K pulse tube coolers that each provide 1.5 W ofcooling at 4.2 K. Final design and construction of the tracker solenoidsbegan during the summer of 2006. This report describes the progress madeon the construction of the tracker solenoids.

Green, Michael A.; Virostek, Steve P.

2007-08-27

227

Convex Diffraction Grating Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

A 1:1 Offner mirror system for imaging off-axis objects is modified by replacing a concave spherical primary mirror that is concentric with a convex secondary mirror with two concave spherical mirrors M1 and M2 of the same or different radii positioned with their respective distances d1 and d2 from a concentric convex spherical diffraction grating having its grooves parallel to the entrance slit of the spectrometer which replaces the convex secondary mirror. By adjusting their distances d1 and d2 and their respective angles of reflection alpha and beta, defined as the respective angles between their incident and reflected rays, all aberrations are corrected without the need to increase the spectrometer size for a given entrance slit size to reduce astigmatism, thus allowing the imaging spectrometer volume to be less for a given application than would be possible with conventional imaging spectrometers and still give excellent spatial and spectral imaging of the slit image spectra over the focal plane.

Chrisp, Michael P. (Inventor)

1999-01-01

228

Reflecting Slit for Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

Optical slit that reflects rather than transmits performs multiple functions for imaging infrared spectrometer. Serves as field reflector, field flattener, and entrance aperture for instrument. Reflecting slit narrow strip of spherical reflecting surface with intersecting spherical reflecting side surfaces that reject radiation originating outside slit region. Precision of slit geometry crucial in optical system.

Page, N. A.; Parks, R. E.; Rodgers, J. M.

1986-01-01

229

Time of flight mass spectrometer  

DOEpatents

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)

1984-01-01

230

Alpha proton x ray spectrometer  

NASA Technical Reports Server (NTRS)

Mars Pathfinder will carry an alpha-proton x ray spectrometer (APX) for the determination of the elemental chemical composition of Martian rocks and soils. The instrument will measure the concentration of all major and some minor elements, including C, N, and O at levels above typically 1 percent.

Rieder, Rudi; Waeke, H.; Economou, T.

1994-01-01

231

IPNS-I chopper spectrometers  

SciTech Connect

We briefly describe the layout and operation of the two chopper experiments at IPNS-I. The recent measurement on solid /sup 4/He by Hilleke et al. provides examples of time-of-flight data from the Low Resolution Chopper Spectrometer.

Price, D.L.; Carpenter, J.M.; Pelizzari, C.A.; Sinha, S.K.; Bresof, I.; Ostrowski, G.E.

1982-01-01

232

Analytical techniques for retrieval of atmospheric composition with the quadrupole mass spectrometer of the Sample Analysis at Mars  

E-print Network

Keywords: Mars Atmosphere Isotopes Mars Science Laboratory Curiosity Rover Sample Analysis at Mars payload on the Mars Science Laboratory (MSL) Curiosity rover, which landed in Mars' Gale Crater in August spectrometer of the Sample Analysis at Mars instrument suite on Mars Science Laboratory Heather B. Franz a

Atreya, Sushil

233

Determination of the spin alignment in heavy-ion reactions with the spin spectrometer  

Microsoft Academic Search

A detailed procedure is outlined that permits one to deduce the spin direction in heavy-ion fusion reactions on an event-by-event basis using data from the spin spectrometer at the Holifield Heavy Ion Research Facility of Oak Ridge National Laboratory. The parameters that govern the ability of the spin spectrometer in determining the spin direction, namely the gamma-ray multiplicity, the multipolarity,

K. J. Honkanen; F. A. Dilmanian; D. G. Sarantites; S. P. Sorensen

1987-01-01

234

The EBIT Calorimeter Spectrometer: A New, Permanent User Facility at the LLNL EBIT  

NASA Technical Reports Server (NTRS)

The EBIT Calorimeter Spectrometer (ECS) has recently been completed and is currently being installed at the EBIT facility at the Lawrence Livermore National Laboratory. The ECS will replace the smaller XRS/EBIT spectrometer that has been in almost continuous operation since 2000. The XRS/EBIT was based on a spare laboratory cryostat and an engineering model detector system from the Suzaku/XRS observatory. The new ECS spectrometer was built from the ground up to be a low maintenance, high performance microcalorimeter spectrometer with 4 eV resolution at 6 keV, 32 detector channels, 10 us event timing, and capable of uninterrupted acquisition sessions of over 70 hours at 50 mK. The XRSIEBIT program has been extremely successful, producing over two-dozen refereed publications on topics such as laboratory astrophysics, atomic physics, nuclear physics, and calibration of the spectrometers for the National Ignition Facility, with many more publications in preparation. The ECS spectrometer will continue this work into the future with improved spectral resolution, integration times, and ease-of-use. We designed the ECS instrument with TES detectors in mind by using the same highly successful magnetic shielding as our laboratory TES cryostats. This design will lead to a future TES instrument at the LLNL EBIT. This proposed future instrument would include a hybrid detector system with 0.8 eV resolution in the band from 0.1-1.0 keV, 2 eV from 0.1-10 keV, and 30 eV from 0.5-100 keV, with high quantum efficiency in each band. Here we discuss the legacy of the XRS/EBIT program, the performance of the new ECS spectrometer, and plans for a future TES spectrometer.

Porter, S.

2007-01-01

235

A field-deployable gamma-ray spectrometer utilizing xenon at high pressure  

SciTech Connect

Prototype gamma-ray spectrometers utilizing xenon gas at high pressure, suitable for applications in the nuclear safeguards, arms control, and nonproliferation communities, have been developed at Brookhaven National Laboratory (BNL). These spectrometers function as ambient-temperature ionization chambers detecting gamma rays with good efficiency in the energy range 50 keV - 2 MeV, with an energy resolution intermediate between semiconductor (Ge) and scintillation (NaI) spectrometers. They are capable of prolonged, low-power operation without a requirement for cryogenic fluids or other cooling mechanisms, and with the addition of small quantities of {sup 3}He gas, can function simultaneously as efficient thermal neutron detectors.

Smith, G.C.; Mahler, G.J.; Yu, B.; Salwen, C.; Kane, W.R.; Lemley, J.R.

1996-10-01

236

A high-resolution imaging x-ray crystal spectrometer for high energy density plasmas  

NASA Astrophysics Data System (ADS)

Adapting a concept developed for magnetic confinement fusion experiments, an imaging crystal spectrometer has been designed and tested for HED plasmas. The instrument uses a spherically bent quartz [211] crystal with radius of curvature of 490.8 mm. The instrument was tested at the Titan laser at Lawrence Livermore National Laboratory by irradiating titanium slabs with laser intensities of 1019-1020 W/cm2. He-like and Li-like Ti lines were recorded, from which the spectrometer performance was evaluated. This spectrometer provides very high spectral resolving power (E/dE > 7000) while acquiring a one-dimensional image of the source.

Chen, Hui; Bitter, M.; Hill, K. W.; Kerr, S.; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P.

2014-11-01

237

A high-resolution imaging x-ray crystal spectrometer for high energy density plasmas.  

PubMed

Adapting a concept developed for magnetic confinement fusion experiments, an imaging crystal spectrometer has been designed and tested for HED plasmas. The instrument uses a spherically bent quartz [211] crystal with radius of curvature of 490.8 mm. The instrument was tested at the Titan laser at Lawrence Livermore National Laboratory by irradiating titanium slabs with laser intensities of 10(19)-10(20) W/cm(2). He-like and Li-like Ti lines were recorded, from which the spectrometer performance was evaluated. This spectrometer provides very high spectral resolving power (E/dE > 7000) while acquiring a one-dimensional image of the source. PMID:25430352

Chen, Hui; Bitter, M; Hill, K W; Kerr, S; Magee, E; Nagel, S R; Park, J; Schneider, M B; Stone, G; Williams, G J; Beiersdorfer, P

2014-11-01

238

Sample rotating turntable kit for infrared spectrometers  

DOEpatents

An infrared spectrometer sample rotating turntable kit has a rotatable sample cup containing the sample. The infrared spectrometer has an infrared spectrometer probe for analyzing the sample and the rotatable sample cup is adapted to receive the infrared spectrometer probe. A reflectance standard is located in the rotatable sample cup. A sleeve is positioned proximate the sample cup and adapted to receive the probe. A rotator rotates the rotatable sample cup. A battery is connected to the rotator.

Eckels, Joel Del (Livermore, CA); Klunder, Gregory L. (Oakland, CA)

2008-03-04

239

Measuring Transmission Efficiencies Of Mass Spectrometers  

NASA Technical Reports Server (NTRS)

Coincidence counts yield absolute efficiencies. System measures mass-dependent transmission efficiencies of mass spectrometers, using coincidence-counting techniques reminiscent of those used for many years in calibration of detectors for subatomic particles. Coincidences between detected ions and electrons producing them counted during operation of mass spectrometer. Under certain assumptions regarding inelastic scattering of electrons, electron/ion-coincidence count is direct measure of transmission efficiency of spectrometer. When fully developed, system compact, portable, and used routinely to calibrate mass spectrometers.

Srivastava, Santosh K.

1989-01-01

240

Electron/proton spectrometer certification documentation analyses  

NASA Technical Reports Server (NTRS)

A compilation of analyses generated during the development of the electron-proton spectrometer for the Skylab program is presented. The data documents the analyses required by the electron-proton spectrometer verification plan. The verification plan was generated to satisfy the ancillary hardware requirements of the Apollo Applications program. The certification of the spectrometer requires that various tests, inspections, and analyses be documented, approved, and accepted by reliability and quality control personnel of the spectrometer development program.

Gleeson, P.

1972-01-01

241

Evidence for collective multi-particle correlations in pPb collisions  

E-print Network

The second-order azimuthal anisotropy Fourier harmonics, v2, are obtained in pPb and PbPb collisions over a wide pseudorapidity (eta) range based on correlations among six or more charged particles. The pPb data, corresponding to an integrated luminosity of 35 inverse nanobarns, were collected during the 2013 LHC pPb run at a nucleon-nucleon center-of-mass energy of 5.02 TeV by the CMS experiment. A sample of semi-peripheral PbPb collision data at sqrt(s[NN])= 2.76 TeV, corresponding to an integrated luminosity of 2.5 inverse microbarns and covering a similar range of particle multiplicities as the pPb data, is also analyzed for comparison. The six- and eight-particle cumulant and the Lee-Yang zeros methods are used to extract the v2 coefficients, extending previous studies of two- and four-particle correlations. For both the pPb and PbPb systems, the v2 values obtained with correlations among more than four particles are consistent with previously published four-particle results. These data support the interpretation of a collective origin for the previously observed long-range (large Delta[eta]) correlations in both systems. The ratios of v2 values corresponding to correlations including different numbers of particles are compared to theoretical predictions that assume a hydrodynamic behavior of a pPb system dominated by fluctuations in the positions of participant nucleons. These results provide new insights into the multi-particle dynamics of collision systems with a very small overlapping region.

CMS Collaboration

2015-02-18

242

Multi-particle and tetrad statistics in numerical simulations of turbulent relative dispersion  

NASA Astrophysics Data System (ADS)

The evolution in size and shape of three and four-particle clusters (triangles and tetrads, respectively) in isotropic turbulence is studied using direct numerical simulations at grid resolution up to 40963 and Taylor-scale Reynolds numbers from 140 to 1000. A key issue is the attainment of inertial range behavior at high Reynolds number, while the small- and large-time limits of ballistic and diffusive regimes, respectively, are also considered in some detail. Tetrad size expressed by the volume (V) and (more appropriately) the gyration radius (R) is shown to display inertial range scaling consistent with a Richardson constant close to 0.56 for two-particle relative dispersion. For tetrads of initial size in a suitable range moments of shape parameters, including the ratio V2/3/R2 and normalized eigenvalues of a moment-of-inertia-like dispersion tensor, show a regime of near-constancy which is identified with inertial-range scaling. Sheet-like structures are dominant in this period, while pancakes and needles are more prevalent at later times. For triangles taken from different faces of each tetrad effects of the initial shape (isosceles right-angled or equilateral) are retained only for about one Batchelor time scale. In the inertial range there is a prevalence of nearly isosceles triangles of two long sides and one short side, representing one particle moving away from the other two which are still close together. In general, measures of shape display asymptotic scaling ranges more readily than measures of size. With some caveats, the simulation results are also compared with the limited literature available for multiparticle cluster dispersion in turbulent flow.

Hackl, J. F.; Yeung, P. K.; Sawford, B. L.

2011-06-01

243

Hydrodynamic mechanisms of spinodal decomposition in confined colloid-polymer mixtures: a multiparticle collision dynamics study.  

PubMed

A multiscale model for a colloid-polymer mixture is developed. The colloids are described as point particles interacting with each other and with the polymers with strongly repulsive potentials, while polymers interact with each other with a softer potential. The fluid in the suspension is taken into account by the multiparticle collision dynamics method (MPC). Considering a slit geometry where the suspension is confined between parallel repulsive walls, different possibilities for the hydrodynamic boundary conditions (b.c.) at the walls (slip versus stick) are treated. Quenching experiments are considered, where the system volume is suddenly reduced (keeping the density of the solvent fluid constant, while the colloid and polymer particle numbers are kept constant) and thus an initially homogeneous system is quenched deeply into the miscibility gap, where it is unstable. For various relative concentrations of colloids and polymers, the time evolution of the growing colloid-rich and polymer-rich domains are studied by molecular dynamics simulation, taking hydrodynamic effects mediated by the solvent into account via MPC. It is found that the domain size [script-l](d)(t) grows with time t as [script-l](d)(t) [proportionality] t(1/3) for stick and (at late stages) as [script-l](d)(t) [proportionality] t(2/3) for slip b.c., while break-up of percolating structures can cause a transient "arrest" of growth. While these findings apply for films that are 5-10 colloid diameters wide, for ultrathin films (1.5 colloid diameters wide) a regime with [script-l](d)(t) [proportionality] t(1/2) is also identified for rather shallow quenches. PMID:23406143

Winkler, Alexander; Virnau, Peter; Binder, Kurt; Winkler, Roland G; Gompper, Gerhard

2013-02-01

244

[Research on algorithm for self-absorption correction based on multi-particles LIBS spectra].  

PubMed

In order to overcome the influence of self-absorption on quantitative analysis, the optimizing process of very fast simulated annealing algorithm was studied. According to basic theory of plasma emission spectrum, a new algorithm for self-absorpton correction based on multi-particles spectra was proposed, and the algorithm flowchart was given. With the self-absorption correction algorithm mentioned above, the spectra of refining slag and blast furnace slag were corrected. The effect of self-ab sorption correction on the quantitative analysis results was analyzed based on calibration free method. Comparison of Boltzmann plots before and after self-absorption correction indicated that the plasma temperatures calculated with spectra after self-absorption correction tended to be uniform, and remained stable around 11,600 K. The Boltzmann plots constructed with plasma spectra of the same particle after self-absorption correction indicated that the intercepts were almost the same except for one group data. With calibration free method and spectra after self-absorption correction, the contents of components in slag were analyzed. For refining slag, quantitative analysis precision of MgO was low. If ignoring the existence of MgO, the relative errors of quantitative analysis results of CaO, Al2 O3 and SiOs were much smaller. For blast furnace slag in which the content of MgO was 8.49%, the relative error of quantitative analysis result of Al2 O3 was 2.38%, which was the smallest. And the relative error of quantitative analysis result of MgO was 28.27%, which was still the biggest. PMID:25532357

Ni, Zhi-Bo; Dong, Feng-Zhong; Chen, Xing-Long; Wang, Jing-Ge; He, Wen-Gan; Fu, Hong-Bo

2014-09-01

245

Signal Processing Issues in Fourier Transform Spectrometers  

Microsoft Academic Search

There are a number of interesting and challenging signal processing problems related to the design of a Fourier Transform Spectrometer (FTS). In this project, we look at a few of these problems in two different types of spectrometers-the Geostationary Imaging Fourier Transform Spectrometer (GIFTS), and a Far Infrared (FIR) FTS. One of the si nal processing challenges in GIFTS is

Monson H. Hayes

2002-01-01

246

ADVANCED METHODS FOR THE COMPUTATION OF PARTICLE BEAM TRANSPORT AND THE COMPUTATION OF ELECTROMAGNETIC FIELDS AND MULTIPARTICLE PHENOMENA  

SciTech Connect

Since 1980, under the grant DEFG02-96ER40949, the Department of Energy has supported the educational and research work of the University of Maryland Dynamical Systems and Accelerator Theory (DSAT) Group. The primary focus of this educational/research group has been on the computation and analysis of charged-particle beam transport using Lie algebraic methods, and on advanced methods for the computation of electromagnetic fields and multiparticle phenomena. This Final Report summarizes the accomplishments of the DSAT Group from its inception in 1980 through its end in 2011.

Alex J. Dragt

2012-08-31

247

The BFKL Pomeron Calculus in zero transverse dimensions: summation of Pomeron loops and generating functional for the multiparticle production processes  

E-print Network

In this paper we address two problems in the BFKL Pomeron calculus in zero transverse dimensions: the summation of the Pomeron loops and the calculation of the processes of multiparticle generation. We introduce a new generating functional for these processes and obtain the evolution equation for it. We argue that in the kinematic range given by $ 1 \\ll \\ln(1/\\as^2) \\ll \\as Y \\ll \\frac{1}{\\as}$, we can reduce the Pomeron calculus to exchange of non-interacting Pomerons with the renormalized amplitude of their interaction with the target. Therefore, the summation of the Pomeron loops can be performed using Mueller, Patel, Salam and Iancu approximation.

E. Levin; A. Prygarin

2007-04-16

248

Group-theoretical construction of finite-momentum and multi-particle operators for lattice hadron spectroscopy  

E-print Network

Determining the spectrum of hadronic excitations from Monte Carlo simulations requires the use of interpolating operators that couple to multi-particle states. Recent algorithmic advances have made the inclusion of multi-hadron operators in spectroscopy calculations a practical reality. In this talk, a procedure for constructing a set of multi-hadron interpolators that project onto the states of interest is described. To aid in the interpretation of simulation data, operators are designed to transform irreducibly under the lattice symmetry group. The identification of a set of optimal single-hadron interpolators for states with non-zero momenta is an essential intermediate step in this analysis.

Justin Foley; John Bulava; You-Cyuan Jhang; Keisuke J. Juge; David Lenkner; Colin Morningstar; Chik Him Wong

2012-05-18

249

Fabrication, Testing and Modeling of the MICE Superconducting Spectrometer Solenoids  

SciTech Connect

The Muon Ionization Cooling Experiment (MICE), an international collaboration sited at Rutherford Appleton Laboratory in the UK, will demonstrate ionization cooling in a section of realistic cooling channel using a muon beam. A five-coil superconducting spectrometer solenoid magnet will provide a 4 tesla uniform field region at each end of the cooling channel. Scintillating fiber trackers within the 400 mm diameter magnet bore tubes measure the emittance of the beam as it enters and exits the cooling channel. Each of the identical 3-meter long magnets incorporates a three-coil spectrometer magnet section and a two-coil section to match the solenoid uniform field into the other magnets of the MICE cooling channel. The cold mass, radiation shield and leads are currently kept cold by means of three two-stage cryocoolers and one single-stage cryocooler. Liquid helium within the cold mass is maintained by means of a re-condensation technique. After incorporating several design changes to improve the magnet cooling and reliability, the fabrication and acceptance testing of the spectrometer solenoids have proceeded. The key features of the spectrometer solenoid magnets, the development of a thermal model, the results of the recently completed tests, and the current status of the project are presented.

Virostek, S.P.; Green, M.A.; Trillaud, F.; Zisman, M.S.

2010-05-16

250

Portable neutron spectrometer/dosimeter  

SciTech Connect

As part of the continuing DOE effort to upgrade personnel neutron dosimetry, the Health Division at Los Alamos has developed a portable, battery-operated, computerized neutron spectrometer/dosimeter. The instrument has a built-in tissue-equivalent LET neutron detector, 128-channel pulse height analyzer with integral liquid crystal display, and a microcomputer system which calculates dose and dose rate from neutrons incident on the detector. The neutron spectrometer/dosimeter is designed around a linear energy transfer (LET) proportional counter. The instrument will, at the user's option, display a raw data spectrum or a spectrum of rad or rem as a function of keV per micron of equivalent tissue. The dosimeter will also calculate and display accumulated dose in millirad and millirem, as well as giving the user neutron dose rates in millirad and millirem per hour.

Waechter, D.A.; Erkkila, B.H.; Vasilik, D.G.

1982-01-01

251

New family of reflective spectrometers  

NASA Astrophysics Data System (ADS)

Three kinds of spectrometers based on off-axis Schmidt and Schmidt-Cassegrain cameras are presented; they have been used for several instruments studies, mainly for European Space Agency and Agenzia Spaziale Italiana. Both dispersive prism and grating based configurations have interesting characteristics, such as: simplicity, low cost, high efficiency, small volume and weight, very low sensitivity to polarization and great flexibility also in multichannel (wavebands) configurations. The image quality is high, even with low relative apertures and great fields of view, allowing a very good correction of smile and keystone. The compensation of the slit curvature induced by a prism disperser is also demonstrated. This family of spectrometers was the topic of three patents, belonging to Selex-Galileo, while the intellectual property belongs to A. Romali et al.

Romoli, Andrea; Simonetti, Francesca; Gambicorti, Lisa; Marchi, Alessandro Zuccaro

2011-01-01

252

Exploiting a Transmission Grating Spectrometer  

SciTech Connect

The availability of compact transmission grating spectrometers now allows an attractive and economical alternative to the more familiar Czerny-Turner configuration for many high-temperature plasma applications. Higher throughput is obtained with short focal length refractive optics and stigmatic imaging. Many more spectra can be obtained with a single spectrometer since smaller, more densely packed optical input fibers can be used. Multiple input slits, along with a bandpass filter, can be used to maximize the number of spectra per detector, providing further economy. Curved slits can correct for the strong image curvature of the short focal length optics. Presented here are the governing grating equations for both standard and high-dispersion transmission gratings, defining dispersion, image curvature, and desired slit curvature, that can be used in the design of improved plasma diagnostics.

Ronald E. Bell

2004-12-08

253

A 4 ? dilepton spectrometer: PEPSI  

NASA Astrophysics Data System (ADS)

A novel positron-electron pair spectroscopy instrument (PEPSI) was designed to measure transitions in the energy region 10-40 MeV. It consists of Nd 2Fe 14B permanent magnets forming a compact 4 ? magnetic filter consisting of 12 positron and 20 electron mini-orange-like spectrometers. The response function of PEPSI has been measured with mono-energetic beams of electrons from 5 to 20 MeV. The PEPSI spectrometer was used for measuring the internal pair conversion coefficient ( ??) of the 15.1 MeV M1 transition from a J? = 1 + state to the ground state in 12C. Our experimental value of ?? = (3.3 ± 0.5) × 10 -3 is in good agreement with theoretical estimates.

Buda, A.; Bacelar, J. C. S.; Ba?anda, A.; van Klinken, J.; Sujkowski, Z.; van der Woude, A.

1993-11-01

254

Imaging X-ray spectrometer  

NASA Technical Reports Server (NTRS)

An X-ray spectrometer for providing imaging and energy resolution of an X-ray source is described. This spectrometer is comprised of a thick silicon wafer having an embedded matrix or grid of aluminum completely through the wafer fabricated, for example, by thermal migration. The aluminum matrix defines the walls of a rectangular array of silicon X-ray detector cells or pixels. A thermally diffused aluminum electrode is also formed centrally through each of the silicon cells with biasing means being connected to the aluminum cell walls and causes lateral charge carrier depletion between the cell walls so that incident X-ray energy causes a photoelectric reaction within the silicon producing collectible charge carriers in the form of electrons which are collected and used for imaging.

Grant, P. A.; Jackson, J. W., Jr.; Alcorn, G. E.; Marshall, F. E. (inventors)

1984-01-01

255

Short wavelength rocketborne infrared spectrometer  

Microsoft Academic Search

An IR spectrometer, used to obtain measurements of faint atmospheric emission spectra from a rocket carrier, is described. The sensor scans the 2.07 to 5.47 micron spectral region at the rate of 2 scan\\/s. The spectral resolution of the sensor, which employs a circular variable filter (CVF), ranges from 1.0 to 3.0%. The entire optical subsection, indium antimonide detector, CVF,

C. L. Wyatt; D. G. Frodsham

1977-01-01

256

The Upper Atmosphere Composition Spectrometer  

Microsoft Academic Search

The Upper Atmosphere Composition Spectrometer (UACS) was flown on the Department of Defense Space Test Program mission S85-1. This paper describes the instrument and discusses examples of its operation in orbit. UACS employs a conventional quadrupole mass filter with a semi-open ionization chamber and a special dual detector system for a large dynamic measurement range. In addition to measuring neutral

D. C. Kayser; W. T. Chater; C. K. Howey; J. B. Pranke

1986-01-01

257

Ultraviolet spectrometer observations of Uranus  

Microsoft Academic Search

The Voyager 2 UV spectrometer was used to scan the Uranus atmosphere at wavelengths from 500-1700 A with a field of view of 0.1 x 0.86 deg. The temperature and composition of the upper atmosphere were determined through occultations of light from gamma Pegasi, nu Geminorum and the sun. The data indicated a substantial gas density (100 million H atoms\\/cu

A. L. Broadfoot; F. Herbert; J. B. Holberg; D. M. Hunten; S. Kumar; B. R. Sandel; D. E. Shemansky; G. R. Smith; R. V. Yelle; D. F. Strobel; H. W. Moos; T. M. Donahue; S. K. Atreya; J. L. Bertaux; J. E. Blamont; J. C. Mcconnell; A. J. Dessler; S. Linick; R. Springer

1986-01-01

258

High resolution hadamard transform spectrometer.  

PubMed

The ir spectrometer described employs alkaline halide lenses, an echelle grating, and a cryogenically cooled doped germanium bolometer as a detector. It is provided for two possible modes of operation: one is a single slit or conventional scan, the other is a multiplex or Hadamard scan. Signal strength, noise characteristics, scanning time, and available computer facilities determine the mode of operation. Sample spectra are presented. PMID:20111540

Hansen, P; Strong, J

1972-03-01

259

Impacts of Limestone Multi-particle Size on Production Performance, Egg Shell Quality, and Egg Quality in Laying Hens  

PubMed Central

This experiment was conducted to evaluate the effects of single or multi-particle size limestone on the egg shell quality, egg production, egg quality and feed intake in laying hens. A total of 280 laying hens (ISA brown) were used in this 10-wk trial. Laying hens were randomly assigned to 4 treatments with 14 replications per treatment and 5 adjacent cages as a replication (hens were caged individually). The experimental treatments were: i) L, basal diet+10% large particle limestone; ii) LS1, basal diet+8% large particle limestone+2% small particle limestone; iii) LS2, basal diet+6% large particle limestone+4% small particle limestone; iv) S, basal diet+10% small particle limestone. The egg production was unaffected by dietary treatments. The egg weight in S treatment was lighter than other treatments (p<0.05). The egg specific gravity in S treatment was lower than other treatments (p<0.05). The eggshell strength and eggshell thickness in S treatment were decreased when compared with other dietary treatments (p<0.05). The laying hens in LS1 and LS2 treatment had a higher average feed intake than the other two treatments (p<0.05). Collectively, the dietary multi-particle size limestone supplementation could be as efficient as large particle size limestone. PMID:25049635

Guo, X. Y.; Kim, I. H.

2012-01-01

260

Multi-Particle Collision Dynamics -- a Particle-Based Mesoscale Simulation Approach to the Hydrodynamics of Complex Fluids  

E-print Network

In this review, we describe and analyze a mesoscale simulation method for fluid flow, which was introduced by Malevanets and Kapral in 1999, and is now called multi-particle collision dynamics (MPC) or stochastic rotation dynamics (SRD). The method consists of alternating streaming and collision steps in an ensemble of point particles. The multi-particle collisions are performed by grouping particles in collision cells, and mass, momentum, and energy are locally conserved. This simulation technique captures both full hydrodynamic interactions and thermal fluctuations. The first part of the review begins with a description of several widely used MPC algorithms and then discusses important features of the original SRD algorithm and frequently used variations. Two complementary approaches for deriving the hydrodynamic equations and evaluating the transport coefficients are reviewed. It is then shown how MPC algorithms can be generalized to model non-ideal fluids, and binary mixtures with a consolute point. The importance of angular-momentum conservation for systems like phase-separated liquids with different viscosities is discussed. The second part of the review describes a number of recent applications of MPC algorithms to study colloid and polymer dynamics, the behavior of vesicles and cells in hydrodynamic flows, and the dynamics of viscoelastic fluids.

G. Gompper; T. Ihle; D. M. Kroll; R. G. Winkler

2008-08-15

261

Ion mobility spectrometer / mass spectrometer (IMS-MS).  

SciTech Connect

The use of Ion Mobility Spectrometry (IMS) in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400). Combining Ion Mobility Spectrometry (IMS) with Mass Spectrometry (MS) is described. The IMS-MS combination overcomes several limitations present in simple IMS systems. Ion mobility alone is insufficient to identify an unknown chemical agent. Collision cross section, upon which mobility is based, is not sufficiently unique or predictable a priori to be able to make a confident peak assignment unless the compounds present are already identified. Molecular mass, on the other hand, is much more readily interpreted and related to compounds. For a given compound, the molecular mass can be determined using a pocket calculator (or in one's head) while a reasonable value of the cross-section might require hours of computation time. Thus a mass spectrum provides chemical specificity and identity not accessible in the mobility spectrum alone. In addition, several advanced mass spectrometric methods, such as tandem MS, have been extensively developed for the purpose of molecular identification. With an appropriate mass spectrometer connected to an ion mobility spectrometer, these advanced identification methods become available, providing greater characterization capability.

Hunka Deborah Elaine; Austin, Daniel E.

2005-07-01

262

Ion Mobility Spectrometer / Mass Spectrometer (IMS-MS).  

SciTech Connect

The use of Ion Mobility Spectrometry (IMS)in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400).Combining Ion Mobility Spectrometry (IMS) with Mass Spectrometry (MS)The IMS-MS combination overcomes several limitations present in simple IMS systems. Ion mobility alone is insufficient to identify an unknown chemical agent. Collision cross section, upon which mobility is based, is not sufficiently unique or predictable a priori to be able to make a confident peak assignment unless the compounds present are already identified. Molecular mass, on the other hand, is much more readily interpreted and related to compounds. For a given compound, the molecular mass can be determined using a pocket calculator (or in one's head) while a reasonable value of the cross-section might require hours of computation time. Thus a mass spectrum provides chemical specificity and identity not accessible in the mobility spectrum alone. In addition, several advanced mass spectrometric methods, such as tandem MS, have been extensively developed for the purpose of molecular identification. With an appropriate mass spectrometer connected to an ion mobility spectrometer, these advanced identification methods become available, providing greater characterization capability.3 AcronymsIMSion mobility spectrometryMAAMaterial Access AreaMSmass spectrometryoaTOForthogonal acceleration time-of-flightTOFtime-of-flight4

Hunka, Deborah E; Austin, Daniel

2005-10-01

263

A microelectromechanical systems-enabled, miniature triple quadrupole mass spectrometer.  

PubMed

Miniaturized mass spectrometers are becoming increasingly capable, enabling the development of many novel field and laboratory applications. However, to date, triple quadrupole tandem mass spectrometers, the workhorses of quantitative analysis, have not been significantly reduced in size. Here, the basis of a field-deployable triple quadrupole is described. The key development is a highly miniaturized ion optical assembly in which a sequence of six microengineered components is employed to generate ions at atmospheric pressure, provide a vacuum interface, effect ion guiding, and perform fragmentation and mass analysis. Despite its small dimensions, the collision cell efficiently fragments precursor ions and yields product ion spectra that are very similar to those recorded using conventional instruments. The miniature triple quadrupole has been used to detect thiabendazole, a common pesticide, in apples at a level of 10 ng/g. PMID:25708099

Wright, Steven; Malcolm, Andrew; Wright, Christopher; O'Prey, Shane; Crichton, Edward; Dash, Neil; Moseley, Richard W; Zaczek, Wojciech; Edwards, Peter; Fussell, Richard J; Syms, Richard R A

2015-03-17

264

An FIR cooled grating spectrometer for the Kuiper Airborne Observatory  

NASA Technical Reports Server (NTRS)

The design and performance of a liquid-He-cooled spectrometer being developed for the Kuiper Airborne Observatory (KAO) to study FIR lines originating in the interstellar medium are discussed. Currently, the spectrometer contains six Ge:Ga photoconductor detectors mounted in integrating cavities and cooled to about 3 K; the collimator focal plane has space for 39 such detectors. The instrument achieves a maximum resolving power of 6000 by means of a 45-cm long echelle grating and is optically capable of operating in the spectral range 25-300 microns. A laboratory spectrum of water vapor, an atmospheric water absorption feature measured from the KAO with Mars as a source, and the forbidden O(2+) emission from W51-IRS1 are shown.

Erickson, E. F.; Haas, M. R.; Hollenbach, D. J.; Simpson, J. P.; Augason, G. C.; Houck, J. R.; Harwit, M. O.; Rank, D. M.

1985-01-01

265

A Shuttle Imaging Spectrometer Experiment for the late 1980's  

NASA Technical Reports Server (NTRS)

The Shuttle Imaging Spectrometer Experiment (SISEX), proposed as a next experimental step in the development of advanced earth remote sensing technology, is capable of imaging the earth's surface simultaneously in 128 spectral bands covering the range from 0.4 to 2.5 micrometers. Laboratory and field measurements have suggested the utility of high-spectral-resolution remote sensing, and an aircraft-borne precursor to the SISEX has demonstrated the ability to distinguish among differing vegetation and rock types - in certain cases making unique identifications. The SISEX instrument utilizes an area-array focal plane, populated by visual- and infrared-sensitive detectors, to acquire simultaneous spatial and spectral information on a line-by-line basis. The spectrum is dispersed by means of a prism spectrometer. The performance analysis indicates that the scientific requirements for radiometric precision can be achieved using optics with an effective circular aperture of 11 cm.

Wellman, J. B.; Goetz, A. F. H.; Herring, M.; Vane, G.

1983-01-01

266

Data Acquisition System for Electron Energy Loss Coincident Spectrometers  

NASA Astrophysics Data System (ADS)

A Data Acquisition System (DAQ) for electron energy loss coincident spectrometers (EELCS) has been developed. The system is composed of a Multiplex Time-Digital Converter (TDC) that measures the flying time of positive and negative ions and a one-dimension position-sensitive detector that records the energy loss of scattering electrons. The experimental data are buffered in a first-in-first-out (FIFO) memory module, then transferred from the FIFO memory to PC by the USB interface. The DAQ system can record the flying time of several ions in one collision, and allows of different data collection modes. The system has been demonstrated at the Electron Energy Loss Coincident Spectrometers at the Laboratory of Atomic and Molecular Physics, USTC. A detail description of the whole system is given and experimental results shown.

Zhang, Chi; Yu, Xiaoqi; Yang, Tao

2005-12-01

267

The AMS (Accelerator Mass Spectrometer) program at LLNL  

SciTech Connect

Livermore will have an operational Accelerator Mass Spectrometer (AMS) by mid-1989 as part of its new Multi-user Tandem Laboratory. The spectrometer was designed primarily for applications in archaeology and the geosciences and was co-funded by the University of California Regents. Radiological control for personnel protection, ion sources and injection systems, the tandem and all beam handling hardware are operated with a distributed processor computer control system. The Tandem is the former University of Washington injector FN which has been upgraded with Dowlish tubes, pelletron charging and SF/sub 6/ gas. Design goals for the AMS system, computer aided operation, automated measurement capability, initial results and some of our intended applications will be presented. 5 refs., 2 figs.

Proctor, I.D.

1988-09-01

268

Scintillation gamma spectrometer for analysis of hydraulic fracturing waste products.  

PubMed

Flowback and produced wastewaters from unconventional hydraulic fracturing during oil and gas explorations typically brings to the surface Naturally Occurring Radioactive Materials (NORM), predominantly radioisotopes from the U238 and Th232 decay chains. Traditionally, radiological sampling are performed by sending collected small samples for laboratory tests either by radiochemical analysis or measurements by a high-resolution High-Purity Germanium (HPGe) gamma spectrometer. One of the main isotopes of concern is Ra226 which requires an extended 21-days quantification period to allow for full secular equilibrium to be established for the alpha counting of its progeny daughter Rn222. Field trials of a sodium iodide (NaI) scintillation detector offers a more economic solution for rapid screenings of radiological samples. To achieve the quantification accuracy, this gamma spectrometer must be efficiency calibrated with known standard sources prior to field deployments to analyze the radioactivity concentrations in hydraulic fracturing waste products. PMID:25734826

Ying, Leong; O'Connor, Frank; Stolz, John F

2015-04-16

269

Miniature Mass Spectrometers on Space and Planetary Missions  

NASA Technical Reports Server (NTRS)

Space flight mass spectrometers contribute our understanding of the origin and evolution of our solar system and even of life itself. This fundamental role has motivated increasing interest in miniature mass spectrometry for planetary missions. Several remarkable new instruments are en route or under development to investigate the composition of planetary bodies such as Mars and comets. For instance, the Sample Analysis at Mars (SAM) suite on the 2009 Mars Science Laboratory (MSL) mission includes a quadrupole mass spectrometer with a sophisticated gas processing system as well as pyrolysis and chemical derivatization protocols for solid samples. Future missions will require even lighter, lower power, and yet more capable mass spectrometers, particularly to analyze samples in situ on planetary surfaces. We have been developing laser-based mass spectrometers for elemental and organic/molecular analysis of rock, ice, or fine particle samples. These typically use time-of-flight (TOF) mass analyzers, which are readily miniaturized and can detect both atomic species and complex organics that occur in a variety of planetary materials. For example, nonvolatile polycyclic aromatic hydrocarbons and kerogen-like macromolecular carbon are found in some carbonaceous meteorites, which derived from asteroid parent bodies. A single focused laser pulse is able to volatilize and ionize some of these compounds for direct TOF analysis. While this is possible without any sample preparation or contact, sensitivity and quantitative performance can improve significantly with some sample handling. As such we have also been examining robotic mechanisms and protocols to accompany space flight mass spectrometers. In addition, sensors in early development may significantly improve these capabilities, via use of techniques such as switchable polarity, ambient pressure, or resonant ionization; tandem mass spectrometry (TOF or ion trap); and chemical imaging.

Brinckerhoff, William

2008-01-01

270

Portable neutron spectrometer and dosimeter  

DOEpatents

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)

1985-01-01

271

MODIS: Moderate Resolution Imaging Spectrometer  

NSDL National Science Digital Library

This brochure describes the Moderate Resolution Imaging Spectrometer (MODIS) instrument on NASA's Terra satellite. The first NASA Earth Observing System (EOS) satellite, Terra, was launched on December 18, 1999, carrying five remote sensors. The most comprehensive EOS sensor is MODIS which offers a unique combination of features: it detects a wide spectral range of electromagnetic energy; it takes measurements at three spatial resolutions (levels of detail); it takes measurements all day, every day; and it has a wide field of view. This continual, comprehensive coverage allows MODIS to complete an electromagnetic picture of the globe every two days.

2002-01-01

272

Optical design and performance of the Ultra-Compact Imaging Spectrometer  

NASA Astrophysics Data System (ADS)

We present the optical design and performance of the Ultra-Compact Imaging Spectrometer (UCIS) currently under development at Caltech's Jet Propulsion Laboratory. The new instrument demonstrates a low optical bench mass of less than 0.5 kg and compact size that enables Mars Rover or other in situ planetary applications. UCIS is an F/4, wide field (30°) design, covering the spectral range 600-2600 nm and is enabled by a simple all aluminum two-mirror telescope and Offner spectrometer. We discuss here the optical design and alignment method that enables this compact and low mass imaging spectrometer and demonstrate successful spectrometer alignment with smile and keystone levels at 2-3% of a pixel width.

Van Gorp, B.; Mouroulis, P.; Wilson, D. W.; Rodriguez, J.; Sobel, H.; Sellar, R. G.; Blaney, D.; Green, R. O.

2011-10-01

273

Instrumental background in gamma-ray spectrometers flown in low earth orbit  

NASA Technical Reports Server (NTRS)

Techniques are presented for calculating the instrumental continuum background in gamma-ray spectrometers flown in low earth orbit (LEO), with special attention given to simple methods developed for scaling from the better-understood measurements and calculations of background in balloon-borne instruments to LEO (Gehrels, 1985). Results are presented in the form of predictions of the background and its components for spectrometers in LEO. These predictions are compared to the measured background for the HEAO 3 gamma-ray spectrometer (Mahoney et al., 1980), and predictions are made for the International Gamma-Ray Astrophysics Laboratory mission and the Nuclear Astrophysics Explorer (Matteson et al., 1990) spectrometers. A comparison is made of various orbit options. It is shown that a critical factor is the number of times the instrument passes through the South Atlantic Anomaly (which is the region of enhanced trapped particle fluxes in LEO) and the depth of penetration on each pass.

Gehrels, Neil

1992-01-01

274

High-resolution compact Johann crystal spectrometer with the Livermore electron beam ion trap  

SciTech Connect

A compact high-resolution ({lambda}/{delta}{lambda}{approx_equal}10 000) spherically bent crystal spectrometer in the Johann geometry was recently installed and tested on the Lawrence Livermore National Laboratory SuperEBIT electron beam ion trap. The curvature of the mica (002) crystal grating allows for higher collection efficiency compared to the flat and cylindrically bent crystal spectrometers commonly used on the Livermore electron beam ion traps. The spectrometer's Johann configuration enables orientation of its dispersion plane to be parallel to the electron beam propagation. Used in concert with a crystal spectrometer, whose dispersion plane is perpendicular to the electron beam propagation, the polarization of x-ray emission lines can be measured.

Robbins, D.L.; Chen, H.; Beiersdorfer, P.; Faenov, A.Ya.; Pikuz, T.A.; May, M.J.; Dunn, J.; Smith, A.J. [Department of Physics, Morehouse College, Atlanta, Georgia 30314 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Multicharged Ions Spectra Data Center of VNIIFTRI, Mendeleevo, Moscow Region, 141570 (Russian Federation); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Department of Physics, Morehouse College, Atlanta, Georgia 30314 (United States)

2004-10-01

275

A high-resolution compact Johann crystal spectrometer with the Livermore electron beam ion trap.  

SciTech Connect

A compact high-resolution ({lambda}/{Delta}{lambda} {approx} 10000) spherically bent crystal spectrometer in the Johann geometry was recently installed and tested on the Lawrence Livermore National Laboratory SuperEBIT electron beam ion trap. The curvature of the mica (002) crystal grating allows for higher collection efficiency compared to the flat and cylindrically bent crystal spectrometers commonly used on the Livermore electron beam ion traps. The spectrometer's Johann configuration enables orientation of its dispersion plane to be parallel to the electron beam propagation. Used in concert with a crystal spectrometer, whose dispersion plane is perpendicular to the electron beam propagation, the polarization of x-ray emission lines can be measured.

Robbins, D L; Chen, H; Beiersdorfer, P; Faenov, A Y; Pikuz, T A; May, M J; Dunn, J; Smith, A J

2004-04-14

276

Engine spectrometer probe and method of use  

NASA Technical Reports Server (NTRS)

The engine spectrometer probe and method of using the same of the present invention provides a simple engine spectrometer probe which is both lightweight and rugged, allowing an exhaust plume monitoring system to be attached to a vehicle, such as the space shuttle. The engine spectrometer probe can be mounted to limit exposure to the heat and debris of the exhaust plume. The spectrometer probe 50 comprises a housing 52 having an aperture 55 and a fiber optic cable 60 having a fiber optic tip 65. The fiber optic tip 65 has an acceptance angle 87 and is coupled to the aperture 55 so that the acceptance angle 87 intersects the exhaust plume 30. The spectrometer probe can generate a spectrum signal from light in the acceptance angle 506 and the spectrum signal can be provided to a spectrometer 508.

Barkhoudarian, Sarkis (Inventor); Kittinger, Scott A. (Inventor)

2006-01-01

277

Elemental concentration logging with a germanium spectrometer  

SciTech Connect

The German deep-well project is currently drilling a scientific well in northeastern Bavaria at the intersection of the African and Northern European tectonic plates. This well is scheduled to be drilled to a depth of {approximately}10 km to study the geochemical processes involved in the alteration of minerals under high temperature and pressure. As an initial stage in this project, a well was drilled to a depth of 4 km within 200 m of the site selected for the deep well. This well was fully cored and extensively logged with both commercial and experimental logging systems. Cores, as well as cuttings and fluids, were extensively analyzed in a well-site laboratory established specifically for that purpose. One of the experimental logging systems run in the 4-km well was a gamma-ray spectrometer that used a {sup 252}Cf source for delayed activation measurements and a neutron generator that produces 14-MeV neutrons for thermal neutron-capture gamma-ray measurements. There were two primary goals of this project. The first was to confirm the validity of elemental concentration determinations from commercial logging equipment, based on NaI(Tl) detectors, in this crystalline rock environment. The commercial equipment determines the elements: aluminum, silicon, sulfur, calcium, titanium, iron, gadolinium, potassium, thorium, and uranium. The second was to determine additional elemental concentrations that can be used to enhance the geo-chemical studies of the crystalline rock mineralogy.

Peterson, C.A.; Schweitzer, J.S. (Schlumberger-Doll Research Center, Ridgefield, CT (United States)); Draxler, J.K.

1991-11-01

278

Compact reflective imaging spectrometer utilizing immersed gratings  

DOEpatents

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)

2006-05-09

279

A variable-dispersion micro-spectrometer  

Microsoft Academic Search

A space-variant variable-dispersion micro-spectrometer has been designed, fabricated, and tested. This spectrometer allows the dispersion to be varied on a pixel-by-pixel basis across the one-dimensional entrance slit. Micro-electro-mechanical mirrors are located at the entrance slit and direct light to one of three different diffraction gratings. A standard grating spectrometer geometry is used to achieve diffraction-limited performance across the 500--1000 nm

Eric Arden Shields

2003-01-01

280

The Nagoya cosmic-ray muon spectrometer  

Microsoft Academic Search

A cosmic-ray muon spectrometer using a solid iron magnet is now under construction. This spectrometer detects muon tracks optically by wide-gap spark chambers triggered by a time-of-flight counter system. The accuracy of the momentum determination of this spectrometer is estimated by a prototype experiment using eight small-scale spark chambers triggered by vertical cosmic-ray muons above 1 GeV\\/c. It is found

S. Shibata; Y. Kamiya; K. Kobayashi; S. Iida

1977-01-01

281

Spectral full-field displays for spectrometers  

NASA Astrophysics Data System (ADS)

The emergence of freeform surfaces in optical systems creates a need for new design methodologies and tools. We present a new analysis tool to facilitate spectrometer designs that leverage freeform surfaces. We demonstrate this new tool for two common all-spherical spectrometer design forms. Using insights from nodal aberration theory, this novel visualization enables the optical designer to efficiently and effectively implement freeform optical surfaces into spectrometers and other dispersive optical instrumentation.

Reimers, Jacob; Thompson, Kevin; Whiteaker, Kevin L.; Rolland, Jannick P.

2014-12-01

282

Stationary Fourier-transform spectrometer.  

PubMed

The performance and the characteristics of an interferometric double-mirror spectrometer with uncollimated light are studied by measuring spectra of different radiation sources. The stationary interferometer is fabricated without a beam splitter or moving components. The measured interferogram visibilities, which are limited by the size of the source aperture, agree with the theoretical predictions for a slit and a circular source aperture. By background subtraction the effect of detection nonuniformity can be radically reduced to increase the dynamics and the resolving power of the spectrometer. We used a mercury pencil lamp for measurement and found that the dynamic range was ~80 dBm. When isolated spectral lines are measured, the resolving power can be improved by squeezing more than half of a spatial interference cycle onto one pixel. The maximum resolving power reached in measuring the spectra of a diode laser was 1600. The instrument is applicable to a wide range of measurements, such as the recording of temporally variant, wideband radiation sources and the monitoring of laser wavelength. PMID:20725388

Junttila, M L

1992-07-20

283

Lunar mass spectrometer test program  

NASA Technical Reports Server (NTRS)

The procedures are described along with results obtained in a test program conducted to demonstrate the performance of a candidate lunar mass spectrometer. The instrument was designed to sample and measure gases believed to exist in the lunar atmosphere at the surface. The subject instrument consists of a cold cathode ion source, a small quadrupole mass analyzer and an off axis electron multiplier ion counting detector. The major program emphasis was placed on demonstrating instrument resolution, sensitivity and S/N ratio over the mass range 0-150 amu and over a partial pressure range from 10 to the minus 9th power to 10 to the minus 13th power torr. Ultrahigh vacuum tests were conducted and the minimum detectable partial pressure for neon, argon, krypton and xenon was successfully determined for the spectrometer using isotopes of these gases. With the exception of neon, the minimum detectable partial pressure is approximately 4 x 10 to the minus 14th power torr for the above gases.

Torney, F. L.; Dobrott, J. R.

1972-01-01

284

High spin nuclear structure studies using the spin spectrometer  

SciTech Connect

The gamma-gamma correlation technique is used to generate two-dimensional histograms of gamma ray energy from gamma-gamma coincidence data. The spin spectrometer at Oak Ridge National Laboratory is used to study the continuum gamma-rays from the reaction /sup 100/Mo + /sup 34/S at 144 MeV beam energy. Double and triple correlation spectra for transitions in rotational bands are obtained which exhibit characteristic valleys. These valleys are shown to depend on the moment of inertia of the rotational bands and the gamma ray spreading width. 5 refs., 4 figs., 4 tabs. (DWL)

Lee, I.Y.

1986-01-01

285

A Feasability Study of the Wheel Electrostatic Spectrometer  

NASA Technical Reports Server (NTRS)

Mars rover missions rely on time-consuming, power-exhausting processes to analyze the Martian regolith. A low power electrostatic sensor in the wheels of a future Mars rover could be used to quickly determine when the rover is driving over a different type of regolith. The Electrostatics and Surface Physics Laboratory at NASA's Kennedy Space Center developed the Wheel Electrostatic Spectrometer as a feasibility study to investigate this option. In this paper, we discuss recent advances in this technology to increase the repeatability of the tribocharging experiments, along with supporting data. In addition, we discuss the development of a static elimination tool optimized for Martian conditions.

Johansen, Michael Ryan; Phillips, James Ralph; Kelley, Joshua David; Mackey, Paul J.; Holbert, Eirik; Clements, Gregory R.; Calle, Carlos I.

2014-01-01

286

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)

1997-04-01

287

SWEPP Gamma-Ray Spectrometer System software design description  

SciTech Connect

To assist in the characterization of the radiological contents of contract-handled waste containers at the Stored Waste Examination Pilot Plant (SWEPP), the SWEPP Gamma-Ray Spectrometer (SGRS) System has been developed by the Radiation Measurements and Development Unit of the Idaho National Engineering Laboratory. The SGRS system software controls turntable and detector system activities. In addition to determining the concentrations of gamma-ray-emitting radionuclides, this software also calculates attenuation-corrected isotopic mass ratios of-specific interest. This document describes the software design for the data acquisition and analysis software associated with the SGRS system.

Femec, D.A.; Killian, E.W.

1994-08-01

288

Simplified electrochemical multi-particle model for LiFePO4 cathodes in lithium-ion batteries  

NASA Astrophysics Data System (ADS)

A simplified physics-based model is developed to predict the performance of an LiFePO4 cathode at various operating and design conditions. Newman's full-order porous-electrode model is simplified using polynomial approximations for electrolyte variables at the electrode-level while a multi-particle model featuring variable solid-state diffusivity is employed at the particle level. The computational time of this reduced-order model is decreased by almost one order of magnitude compared to the full-order model without sacrificing the accuracy of the results. The model is general and can be used to expedite the simulation of any composite electrode with active-material particles of non-uniform properties (e.g., size, contact resistance, material chemistry etc.). In a broader perspective, this model is of practical value for electric vehicle power train simulations and battery management systems.

Mastali Majdabadi, Mehrdad; Farhad, Siamak; Farkhondeh, Mohammad; Fraser, Roydon A.; Fowler, Michael

2015-02-01

289

Start-to-end Beam Optics Development and Multi-particle Tracking for the ILC Positron Source  

SciTech Connect

Undulator-based positron source is adopted as the ILC baseline design. Complete optics to transport the positron beam having large angular divergence and large energy spread from an immersed thin Ti target to the entrance of the 5 GeV damping ring injection line is developed. Start-to-end multi-particle tracking through the beamline is performed including the optical matching device, capture system, transport system, superconducting booster linac, spin rotators, and energy compressor. It shows that 49.8% of the positrons from the target are captured within the damping ring 6-D acceptance--A{sub x} + A{sub y} {le} 0.09 m and {Delta}E x {Delta}z ({+-} 25 MeV) x ({+-} 3.46cm)--at the entrance of the damping ring injection line. The field and alignment errors and orbit correction are analyzed.

Zhou, F.a Batygin, Y.; Nosochkov, Y.; Sheppard, J.C.; Woodley, M.D.; /SLAC

2007-01-25

290

A zero dead-time multi-particle time and position sensitive detector based on correlation between brightness and amplitude.  

PubMed

A new multi-particle time and position sensitive detector using only a set of microchannel plates, a waveform digitizer, a phosphor screen, and a CMOS camera is described. The assignment of the timing information, as taken from the microchannel plates by fast digitizing, to the positions, as recorded by the camera, is based on the COrrelation between the BRightness of the phosphor screen spots, defined as their integrated intensity and the Amplitude of the electrical signals (COBRA). Tests performed by observing the dissociation of HeH, the fragmentation of H3 into two or three fragments, and the photo-double-ionization of Xenon atoms are presented, which illustrate the performances of the COBRA detection scheme. PMID:25725834

Urbain, X; Bech, D; Van Roy, J-P; Géléoc, M; Weber, S J; Huetz, A; Picard, Y J

2015-02-01

291

A zero dead-time multi-particle time and position sensitive detector based on correlation between brightness and amplitude  

NASA Astrophysics Data System (ADS)

A new multi-particle time and position sensitive detector using only a set of microchannel plates, a waveform digitizer, a phosphor screen, and a CMOS camera is described. The assignment of the timing information, as taken from the microchannel plates by fast digitizing, to the positions, as recorded by the camera, is based on the COrrelation between the BRightness of the phosphor screen spots, defined as their integrated intensity and the Amplitude of the electrical signals (COBRA). Tests performed by observing the dissociation of HeH, the fragmentation of H3 into two or three fragments, and the photo-double-ionization of Xenon atoms are presented, which illustrate the performances of the COBRA detection scheme.

Urbain, X.; Bech, D.; Van Roy, J.-P.; Géléoc, M.; Weber, S. J.; Huetz, A.; Picard, Y. J.

2015-02-01

292

Development of a Submillimeter-Wavelength Immersion Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The broad goal of this project was to develop a broadband, moderate-resolution spectrometer for submillimeter wavelengths. Our original approach was to build an immersion grating spectrometer, and as such, the first step was to identify the best material (lowest loss, highest index) for the grating medium, and to characterize its properties at the foreseen optical-bench operating temperature of 1.5 K. To this end, we put our initial efforts into upgrading an existing laboratory submillimeter Fourier transform spectrometer, which allowed us to carry out the requisite materials measurements. The associated cryogenic detector dewar was also redesigned and rebuilt to carry out this work. This dewar houses the 1.5 K detector and the filter wheel used in the materials characterization. Our goal was to have the beam propagate through the samples as uniformly as possible, so the optics were redesigned to allow for the samples to be traversed by a well-defined collimated beam. The optics redesign also placed the samples at an image of the aperture stop located within the FTS. After the rebuild, we moved into the testing phase.

Phillips, T. G.

2001-01-01

293

Miniature mass spectrometer systems based on a microengineered quadrupole filter.  

PubMed

Two miniature mass spectrometer systems based on a microengineered quadrupole mass filter have been developed. One of the instruments has a footprint of 27 cm x 20 cm and is intended for laboratory use when space is at a premium. The other is portable and intended for use in the field. It is battery powered, weighs 14.9 kg, and is housed in a rugged case. This is the first example of a portable mass spectrometer incorporating an analyzer fabricated using microelectromechanical systems (MEMS) techniques. The starting material for construction of the filters is a bonded silicon on insulator substrate, which is selectively etched using batch processing techniques to form coupling optics and springs that accurately hold 0.5 mm diameter stainless steel rods in the required geometry. Assembled filters measure 35 mm x 6 mm x 1.5 mm and are mounted, together with an ion source and channeltron detector, in small, interchangeable cartridges, which plug into a 220 cm(3) vacuum chamber. Recovery from accidental contamination or when servicing is required can be achieved within 5-10 min, as the cartridge is easily exchanged with a spare. A potential application to environmental monitoring has been investigated. The headspace above water spiked with dibutyl mercaptan was sampled with a solid phase microextraction (SPME) fiber, which was then injected directly into the vacuum chamber of the mass spectrometer. Using this method, the limit of detection was found to be approximately 5 ppm for a 15 s sampling period. PMID:20108919

Malcolm, Andrew; Wright, Steven; Syms, Richard R A; Dash, Neil; Schwab, Marc-André; Finlay, Alan

2010-03-01

294

HySens-DAIS/ROSIS Imaging Spectrometers at DLR  

NASA Astrophysics Data System (ADS)

Airborne imaging spectroscopy has undergone a rapid development over the last decade. The number of research groups making use of this technology has increased by an order of a magnitude. Starting from the late 1980s at the DLR research center 'Oberpfaffenhofen' spectroscopic earth observation facilities have been continuously improved in order to be able to provide reliable imaging spectrometer data to the scientific community. At the current stage the integrated hyperspectral facilities at DLR Cluster for Applied Remote Sensing consists of the two imaging spectrometers DAIS 7915 and ROSIS, a laboratory calibration facility and the respective processing and archiving facilities. As an additional important factor in airborne remote sensing access to a DLR-own fleet of research aircraft (Dornier Do228, Cessna 208B Grand-Caravan, FALCON 20 E5 jet) is granted. Numerous imaging spectrometer campaigns have been carried out during the last years with flight activities all over Europe. Currently the two airborne imaging sensors are identified by the European Commission as a mayor research infrastructure and supported in a 3 year project. In the frame of this project hyperspectral data sets will be acquired over different test areas proposed by international research teams. In this paper the installation of the facility in an European research environment, the technical components as well as the currently ongoing research activities will be described. A list of already acquired data sets and the corresponding thematic applications is shown. An outlook to future improvements including new sensor initiatives is given.

Mueller, Andreas A.; Hausold, Andrea; Strobl, Peter

2002-01-01

295

Investigating the rp-process with the Canadian Penning trap mass spectrometer  

Microsoft Academic Search

The Canadian Penning trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of nuclides with short half-lives. Since the previous ENAM conference, many significant modifications to the apparatus were implemented to improve both the precision and efficiency of measurement, and now more than 60 radioactive isotopes have been measured with half-lives as short as one second

J. A. Clark; R. C. Barber; B. Blank; C. Boudreau; F. Buchinger; J. E. Crawford; J. P. Greene; S. Gulick; J. C. Hardy; A. A. Hecht; A. Heinz; J. K. P. Lee; A. F. Levand; B. F. Lundgren; R. B. Moore; G. Savard; N. D. Scielzo; D. Seweryniak; K. S. Sharma; G. D. Sprouse; W. Trimble; J. Vaz; J. C. Wang; Y. Wang; B. J. Zabransky; Z. Zhou

2005-01-01

296

HYSPEC : A CRYSTAL TIME OF FLIGHT HYBRID SPECTROMETER FOR THE SPALLATION NEUTRON SOURCE  

Microsoft Academic Search

This document lays out a proposal by the Instrument Development Team (IDT) composed of scientists from leading Universities and National Laboratories to design and build a conceptually new high-flux inelastic neutron spectrometer at the pulsed Spallation Neutron Source (SNS) at Oak Ridge. This instrument is intended to supply users of the SNS and scientific community, of which the IDT is

S. M. SHAPIRO; I. A. ZALIZNYAK

2002-01-01

297

A compact, multiangle electron spectrometer for ultraintense laser-plasma interaction experiments  

Microsoft Academic Search

Experiments on the multiterawatt (MTW) laser at the Laboratory for Laser Energetics will study the effect of the focal-spot shape on the forward acceleration and collimation of electrons. A compact electron spectrometer has been developed to record the energy spectra of electrons ejected in the interaction of the laser at multiple angular locations simultaneously. The modular system with replaceable magnets

O. V. Gotchev; P. Brijesh; P. M. Nilson; C. Stoeckl; D. D. Meyerhofer

2008-01-01

298

Lunar mass spectrometer test program  

NASA Technical Reports Server (NTRS)

The procedures used and the results are described, which were obtained in a test program to demonstrate the performance of a candidate lunar mass spectrometer. The instrument was designed to sample and measure gases believed to exist in the lunar atmosphere at the surface. The instrument consists of a cold cathode ion source, a small quadrupole mass analyzer, and an off-axis electron multiplier ion-counting detector. Instrument resolution, sensitivity, and S/N ratio were demonstrated over the mass range 0-150 amu and over a partial pressure range from ntorr to ptorr. The subject analyzer was also prepared for extended testing, in conjunction with two other candidate instruments, in a large molecular beam vacuum facility.

Torney, F. L.; Dobrott, J. R.

1971-01-01

299

NA62 Low Mass Spectrometer  

NASA Astrophysics Data System (ADS)

The NA62 experiment at CERN aims at a precision measurement of the ultra-rare decay K^+ rightarrow ?^+?bar?. A low mass (˜ 1.8%X0) spectrometer, whose construction is ongoing, has been designed to track charged kaon decays products. The system operates in vacuum, and will be operative in October 2014, when the first physics run is scheduled. The straw detector is made of 4 stations, each equipped with 1792 straws, arranged in 4 views (X, Y, U and V). A high aperture magnet (MNP33), placed between the second and the third chamber, provides a 0.36T dipole vertical B-field, required to measure the momentum of the charged particles. A 64-straws prototype was constructed in 2010. It was used as test bench for electronics commissioning and detector characterization. Time resolution and space-time relation were measured. A first test with a full chamber and final beam setup was performed in November 2012.

Palladino, V.

2014-06-01

300

The Geostationary Fourier Transform Spectrometer  

NASA Technical Reports Server (NTRS)

The Geostationary Fourier Transform Spectrometer (GeoFTS) is an imaging spectrometer designed for a geostationary orbit (GEO) earth science mission to measure key atmospheric trace gases and process tracers related to climate change and human activity. GEO allows GeoFTS to continuously stare at a region of the earth for frequent sampling to capture the variability of biogenic fluxes and anthropogenic emissions from city to continental spatial scales and temporal scales from diurnal, synoptic, seasonal to interannual. The measurement strategy provides a process based understanding of the carbon cycle from contiguous maps of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and chlorophyll fluorescence (CF) collected many times per day at high spatial resolution (2.7kmx2.7km at nadir). The CO2/CH4/CO/CF measurement suite in the near infrared spectral region provides the information needed to disentangle natural and anthropogenic contributions to atmospheric carbon concentrations and to minimize uncertainties in the flow of carbon between the atmosphere and surface. The half meter cube size GeoFTS instrument is based on a Michelson interferometer design that uses all high TRL components in a modular configuration to reduce complexity and cost. It is self-contained and as independent of the spacecraft as possible with simple spacecraft interfaces, making it ideal to be a "hosted" payload on a commercial communications satellite mission. The hosted payload approach for measuring the major carbon-containing gases in the atmosphere from the geostationary vantage point will affordably advance the scientific understating of carbon cycle processes and climate change.

Key, Richard; Sander, Stanley; Eldering, Annmarie; Blavier, Jean-Francois; Bekker, Dmitriy; Manatt, Ken; Rider, David; Wu, Yen-Hung

2012-01-01

301

Design of a portable microfiber optic spectrometer  

Microsoft Academic Search

Spectrum examination is widely used in scientific research and production. With the development of scientific research and production, the trend of spectrum examination is from indoor to outdoor in situ examination and on-line monitor. So the spectrometer is required to be more minimal. A new type of portable micro fiber spectrometer, using CCD, blaze grating, and two spherical mirror, a

Jian-Ping Tong; Yang Yang; Cheng-Hua Sui; Dang-Yang Xu; Fei Wang

2010-01-01

302

MAGNETIC DEFLECTION MASS SPECTROMETER May 6, 1970  

E-print Network

of building flight mass spec- trometers commensurate with the Apollo 17 flight schedules. Refer to Figures 1ALSEP MAGNETIC DEFLECTION MASS SPECTROMETER May 6, 1970 Dr. J. H. HOFFM}u~ Principal Scientist FOR TYPE OF MASS SPECTROMETER PROPOSED II. STATUS REPORT A. CHRONOLOGY OF DEVELOPMEXT OF LUNAR MASS

Rathbun, Julie A.

303

Signal Processing Issues in Fourier Transform Spectrometers  

NASA Astrophysics Data System (ADS)

There are a number of interesting and challenging signal processing problems related to the design of a Fourier Transform Spectrometer (FTS). In this project, we look at a few of these problems in two different types of spectrometers-the Geostationary Imaging Fourier Transform Spectrometer (GIFTS), and a Far Infrared (FIR) FTS. One of the si nal processing challenges in GIFTS is the reduction of the massive data rate (2.4 x 109 bps) to an affordable telemetry rate of less than 60 Mbps. Since the GIFTS interferograms are heavily over-sampled, the first step is to decimate (down-sample) the interferograms with minimal distortion while keeping the signal processing algorithms simple enough to be implemented in the GIFTS hardware. Therefore, the first problem we looked at was the design of the decimation filters. Specifically, we performed a detailed analysis of two competing approaches that were being considered. The first, proposed by the Space Dynamics Lab (SDL), was to use a double sideband (real) band-pass filter. The second, proposed by Lincoln Laboratories (LL), was to use a single sideband (complex) band-pass filter. What the study showed was that a complex filter (LL approach) results in a savings of about 25% in the filtering requirements for the long-wave band, while in the mid-wave band the savings are approximately 50%. As a result, the decision was made to use a complex filter. Once the decision to use a complex filter had been made, we looked at some of the consequences of this decision. The most significant of these was the discovery that, with a complex filter, it is possible to extend the long-wave IR band beyond the folding frequency of 1174/cm and recover the SO2 line at 1176.5/cm. What this requires is the design of a band-pass decimation filter with a wider passband, and consequently of higher order. Specifically, it was shown that with about 25% more filter operations, the elusive SO2 line, believed to be irretrievable, could in fact be recovered. While working on the decimation filtering requirements, an issue arose with respect to how the 16-bit long-wave interferogram data should be processed by a 15-bit USES chip. There were two approaches being considered, and each one had at least one serious drawback. Therefore, given the nature of the data that is to be processed by the USES chip, we developed an efficient loss-less encoder that is robust to errors, and is easily decoded. Since the encoder eliminates the drawbacks of the other two approaches, and greatly simplifies the signal processing requirements, the downlink board is currently being redesigned to include this encoder. The last problem that was looked at involved an investigation into the optimum sampling strategy in the design of a far infrared FTS. The problem was to minimize the amount of spectral noise that is induced by non-uniform mirror velocity.

Hayes, Monson H.

2002-12-01

304

Photoelectronmultiple-photofragment coincidence spectrometer K. A. Hanold,a)  

E-print Network

is used for collection of multiple photofragments up to 8 in coincidence. This multiparticle detector uses photofragments. The detector was demonstrated to record all three particles produced in a single three- viously used in studies of three-body dissociation processes yielding charged atomic and molecular

Continetti, Robert E.

305

Measurements of neutron energy spectra from 7Li(p,n)7Be reaction with Bonner sphere spectrometer, Nested Neutron Spectrometer and ROSPEC.  

PubMed

Neutron spectrometry measurements were carried out at the McMaster Accelerator Laboratory (MAL), which is equipped with a 3-MV Van de Graaff-type accelerator. Protons were accelerated onto a thick natural lithium target inducing the (7)Li(p,n)(7)Be threshold reaction. Depending on the proton energy, slightly different poly-energetic neutron fields were produced. Neutron spectra were measured at two incident proton energies: 2.15 and 2.24 MeV, which produced poly-energetic neutrons with maximum kinetic energies of 401 and 511 keV, respectively. Measurements were performed at a distance of 1.5 m from the target in the forward direction with three different instruments: Bonner sphere spectrometer, Nested Neutron Spectrometer and ROtational proton recoil SPECtrometer. PMID:24298169

Atanackovic, J; Matysiak, W; Witharana, S; Dubeau, J; Waker, A J

2014-10-01

306

The GRAVITY spectrometers: optical design and first light  

NASA Astrophysics Data System (ADS)

Operating on 6 interferometric baselines, i.e. using all 4 unit telescopes (UTs) of the Very Large Telescope Interferometer (VLTI) simultaneously, the 2nd generation VLTI instrument GRAVITY will deliver narrow-angle astrometry with 10?as accuracy at the infrared K-band. At this angular resolution, GRAVITY will e.g. be able to detect the positional shift of the photo-center of a flare at the Galactic Center within its orbital timescale of about 20 minutes, using the observed motion of the flares as dynamical probes of the gravitational field around the supermassive black hole Sgr A*. Within the international GRAVITY consortium, the 1. Physikalische Institut of the University of Cologne is responsible for the development and construction of the two spectrometers of the camera system: one for the science object, and one for the fringe tracking object, both being operated in cryo-vacuum conditions. In this contribution we describe the basic functionality of the two units and present the final optical design of the two spectrometers as it got realised successfully until end of 2013 with minor changes to the Final Design Review (FDR) of October 2011. In addition we present some of the first light images of the two spectrometers, taken at the laboratory of the Cologne institute between Dec. 2012 and Oct. 2013 respectively. By the end of 2013 both spectrometers got transferred to the PI institute of GRAVITY, the Max-Planck-Institute for Extraterrestrial Physics, where at the time of writing they are undergoing system-level testing in combination with the other sub-systems of GRAVITY.

Straubmeier, Christian; Yazici, Senol; Wiest, Michael; Wank, Imke; Fischer, Sebastian; Eisenhauer, Frank; Perrin, Guy; Perraut, Karine; Brandner, Wolfgang; Amorim, Antonio; Schöller, Markus; Eckart, Andreas

2014-07-01

307

The Moon Mineralogy (M3) Imaging Spectrometer: Early Assessment of the Spectral, Radiometric, Spatial and Uniformity Properties  

NASA Technical Reports Server (NTRS)

The Moon Mineralogy Mapper's (M3) is a high uniformity and high signal-to-noise ratio NASA imaging spectrometer that is a guest instrument on the Indian Chandrayaan-1 Mission to the Moon. The laboratory measured spectral, radiometric, spatial, and uniformity characteristics of the M3 instrument are given. The M3 imaging spectrometer takes advantage of a suite of critical enabling capabilities to achieve its measurement requirement with a mass of 8 kg, power usage of 15 W, and volume of 25X18X12 cm. The M3 detector and spectrometer are cooled by a multi-stage passive cooler. This paper presents early M3 performance assessment results.

Green, Robert O.; Pieters, C. M.; Boardman, J.; Barr, D.; Bruce, C.; Bousman, J.; Chatterjee, A.; Eastwood, M.; Essandoh, V.; Geier, S.; Glavich, T.; Green, R.; Haemmerle, V.; Hyman, S.; Hovland, L.; Koch, T.; Lee, K.; Lundeen, S.; Motts, E.; Mouroulis, P.; Paulson, S.; Plourde, K.; Racho, C.; Robinson, D.; Rodriquez, J.

2009-01-01

308

Comparison of COSPEC and two miniature ultraviolet spectrometer systems for SO2 measurements using scattered sunlight  

USGS Publications Warehouse

The correlation spectrometer (COSPEC), the principal tool for remote measurements of volcanic SO2, is rapidly being replaced by low-cost, miniature, ultraviolet (UV) spectrometers. We compared two of these new systems with a COSPEC by measuring SO2 column amounts at Ki??lauea Volcano, Hawaii. The two systems, one calibrated using in-situ SO2 cells, and the other using a calibrated laboratory reference spectrum, employ similar spectrometer hardware, but different foreoptics and spectral retrieval algorithms. Accuracy, signal-to-noise, retrieval parameters, and precision were investigated for the two configurations of new miniature spectrometer. Measurements included traverses beneath the plumes from the summit and east rift zone of Ki??lauea, and testing with calibration cells of known SO2 concentration. The results obtained from the different methods were consistent with each other, with <8% difference in estimated SO2 column amounts up to 800 ppm m. A further comparison between the COSPEC and one of the miniature spectrometer configurations, the 'FLYSPEC', spans an eight month period and showed agreement of measured emission rates to within 10% for SO2 column amounts up to 1,600 ppm m. The topic of measuring high SO2 burdens accurately is addressed for the Ki??lauea measurements. In comparing the foreoptics, retrieval methods, and resultant implications for data quality, we aim to consolidate the various experiences to date, and improve the application and development of miniature spectrometer systems. ?? Springer-Verlag 2006.

Elias, T.; Sutton, A.J.; Oppenheimer, C.; Horton, K.A.; Garbeil, H.; Tsanev, V.; McGonigle, A.J.S.; Williams-Jones, G.

2006-01-01

309

Miniature Ion-Mobility Spectrometer  

NASA Technical Reports Server (NTRS)

The figure depicts a proposed miniature ion-mobility spectrometer that would be fabricated by micromachining. Unlike prior ion-mobility spectrometers, the proposed instrument would not be based on a time-of-flight principle and, consequently, would not have some of the disadvantageous characteristics of prior time-of-flight ion-mobility spectrometers. For example, one of these characteristics is the need for a bulky carrier-gas-feeding subsystem that includes a shutter gate to provide short pulses of gas in order to generate short pulses of ions. For another example, there is need for a complex device to generate pulses of ions from the pulses of gas and the device is capable of ionizing only a fraction of the incoming gas molecules; these characteristics preclude miniaturization. In contrast, the proposed instrument would not require a carrier-gas-feeding subsystem and would include a simple, highly compact device that would ionize all the molecules passing through it. The ionization device in the proposed instrument would be a 0.1-micron-thick dielectric membrane with metal electrodes on both sides. Small conical holes would be micromachined through the membrane and electrodes. An electric potential of the order of a volt applied between the membrane electrodes would give rise to an electric field of the order of several megavolts per meter in the submicron gap between the electrodes. An electric field of this magnitude would be sufficient to ionize all the molecules that enter the holes. Ionization (but not avalanche arcing) would occur because the distance between the ionizing electrodes would be less than the mean free path of gas molecules at the operating pressure of instrument. An accelerating grid would be located inside the instrument, downstream from the ionizing membrane. The electric potential applied to this grid would be negative relative to the potential on the inside electrode of the ionizing membrane and would be of a magnitude sufficient to generate a moderate electric field. Positive ions leaving the membrane holes would be accelerated in this electric field. The resulting flux of ions away from the ionization membrane would create a partial vacuum that would draw more of the gas medium through the membrane. The figure depicts a filter electrode and detector electrodes located along the sides of a drift tube downstream from the accelerator electrode. These electrodes would apply a transverse AC electric field superimposed on a ramped DC electric field. The AC field would effect differential transverse dispersal of ions. At a given instant of time, the trajectories of most of the ions would be bent toward the electrodes, causing most of the ions to collide with the electrodes and thereby become neutralized. The DC field would partly counteract the dispersive effect of the AC field, straightening the trajectories of a selected species of ions; the selection would vary with the magnitude of the applied DC field. The straightening of the trajectories of the selected ions would enable them to pass into the region between the detector electrodes. Depending on the polarity of the voltage applied to the detector electrodes, the electric field between the detector electrodes would draw the selected ions to one of these electrodes. Hence, the current collected by one of the detector electrodes would be a measure of the abundance of ions of the selected species. The ramping of the filter- electrode DC voltage would sweep the selection of ions through the spectrum of ionic species.

Hartley, Frank T.

2006-01-01

310

Inorganic Chemistry Laboratory  

NSDL National Science Digital Library

This Web site depicts the work of the University of Oxford's Inorganic Chemistry Laboratory in the experimental and theoretical aspects of catalytic systems, bioinorganic, co-ordination, organometallic, structural, surface, and solid state chemistry. The site provides a brief summary of the early professors of the department including Oddling who formulated the periodic table, and two noble prize winners, Soddy and Hinshelwood. Students and educators can discover the exciting research endeavors taken on by the twenty academic staff and over one hundred postdoctoral workers, graduate students, Part II chemists, and other academic visitors. The site also describes the instrumentation used at the laboratory including NMR, CMX, and CI/FI spectrometers and various diffractometers.

311

Preliminary Analysis of the Multisphere Neutron Spectrometer  

NASA Technical Reports Server (NTRS)

Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from galactic cosmic radiation. Crews of future high-speed commercial aircraft flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the Atmospheric Ionizing Radiation (AIR) Project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on five flights of a NASA ER-2 high-altitude aircraft. The primary AIR instrument was a highly sensitive extended-energy multisphere neutron spectrometer with lead and steel shells placed within the moderators of two of its 14 detectors to enhance response at high energies. Detector responses were calculated for neutrons and charged hadrons at energies up to 100 GeV using MCNPX. Neutron spectra were unfolded from the measured count rates using the new MAXED code. We have measured the cosmic-ray neutron spectrum (thermal to greater than 10 GeV), total neutron fluence rate, and neutron effective dose and dose equivalent rates and their dependence on altitude and geomagnetic cutoff. The measured cosmic-ray neutron spectra have almost no thermal neutrons, a large "evaporation" peak near 1 MeV and a second broad peak near 100 MeV which contributes about 69% of the neutron effective dose. At high altitude, geomagnetic latitude has very little effect on the shape of the spectrum, but it is the dominant variable affecting neutron fluence rate, which was 8 times higher at the northernmost measurement location than it was at the southernmost. The shape of the spectrum varied only slightly with altitude from 21 km down to 12 km (56 - 201 grams per square centimeter atmospheric depth), but was significantly different on the ground. In all cases, ambient dose equivalent was greater than effective dose for cosmic-ray neutrons.

Goldhagen, P.; Kniss, T.; Wilson, J. W.; Singleterry, R. C.; Jones, I. W.; VanSteveninck, W.

2003-01-01

312

Miniature quadrupole mass spectrometer array  

NASA Technical Reports Server (NTRS)

The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

1998-01-01

313

Miniature quadrupole mass spectrometer array  

NASA Technical Reports Server (NTRS)

The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

1997-01-01

314

High-Resolution Mass Spectrometers  

NASA Astrophysics Data System (ADS)

Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

Marshall, Alan G.; Hendrickson, Christopher L.

2008-07-01

315

Spectrometer for cluster ion beam induced luminescence  

NASA Astrophysics Data System (ADS)

A spectrometer to detect the ultra-weak luminescence originated by the collision of cluster ions on the surfaces of solid materials was constructed. This spectrometer consists of 11 photomultipliers with band-pass interference filters that can detect the luminescence within the wavelength ranging from 300 to 700 nm and of a photomultiplier without filter. The calibration of the detection system was performed using the photons emitted from a strontium aluminate fluorescent tape and from a high temperature tungsten filament. Preliminary measurements show the ability of this spectrometer to detect the cluster ion beam induced luminescence.

Ryuto, H.; Musumeci, F.; Sakata, A.; Takeuchi, M.; Takaoka, G. H.

2015-02-01

316

Gas sampling system for a mass spectrometer  

DOEpatents

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.

2003-12-30

317

Spectrometer for cluster ion beam induced luminescence.  

PubMed

A spectrometer to detect the ultra-weak luminescence originated by the collision of cluster ions on the surfaces of solid materials was constructed. This spectrometer consists of 11 photomultipliers with band-pass interference filters that can detect the luminescence within the wavelength ranging from 300 to 700 nm and of a photomultiplier without filter. The calibration of the detection system was performed using the photons emitted from a strontium aluminate fluorescent tape and from a high temperature tungsten filament. Preliminary measurements show the ability of this spectrometer to detect the cluster ion beam induced luminescence. PMID:25725822

Ryuto, H; Musumeci, F; Sakata, A; Takeuchi, M; Takaoka, G H

2015-02-01

318

A preliminary design study for a cosmic X-ray spectrometer  

NASA Technical Reports Server (NTRS)

The results are described of theoretical and experimental investigations aimed at the development of a curved crystal cosmic X-ray spectrometer to be used at the focal plane of the large orbiting X-ray telescope on the third High Energy Astronomical Observatory. The effort was concentrated on the development of spectrometer concepts and their evaluation by theoretical analysis, computer simulation, and laboratory testing with breadboard arrangements of crystals and detectors. In addition, a computer-controlled facility for precision testing and evaluation of crystals in air and vacuum was constructed. A summary of research objectives and results is included.

1972-01-01

319

Investigations of 2? decay measured by low background HPGe spectrometer OBELIX  

SciTech Connect

A low background high sensitive HPGe spectrometer OBELIX was installed at the Modane Underground Laboratory (LSM, France, 4800 m w.e.). The detector was designed to measure a contamination of enriched isotopes and radio-impurities in construction materials, to investigate rare nuclear processes such as resonance neutrinoless double electron capture and two-neutrino double beta decay to excited states of daughter nuclei. Spectrometer sensitivity, contamination of NEMO-3 sources and results of 2?2?{sup ?} decay of {sup 100}Mo to the 0{sup +} (1130 keV) and 2{sup +} (540 keV) excited states as well as future plans for OBELIX detector are given.

Rukhadze, Ekaterina [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Collaboration: OBELIX Collaboration; SuperNEMO Collaboration

2013-12-30

320

Electron pair emission detected by time-of-flight spectrometers: Recent progress  

SciTech Connect

We present results for electron coincidence spectroscopy using two time-of-flight (ToF) spectrometers. Excited by electron impact, the energy and momentum distribution of electron pairs emitted from the Cu(111) surface are resolved and a spectral feature related to the Shockley surface state is identified. By combining the two ToF spectrometers with a high-order harmonic generation light source, we demonstrate double photoemission spectroscopy in the laboratory that required synchrotron radiation in the past. Utilizing this setup, we report results for (?,2e) on NiO(001) on Ag(001) excited with light at 30?eV photon energy.

Huth, Michael; Schumann, Frank O. [Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle (Germany); Chiang, Cheng-Tien; Trützschler, Andreas; Kirschner, Jürgen [Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle (Germany); Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, D-06120 Halle (Saale) (Germany); Widdra, Wolf [Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, D-06120 Halle (Saale) (Germany); Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle (Germany)

2014-02-10

321

SETA-Hyperspectral Imaging Spectrometer for Marco Polo mission.  

NASA Astrophysics Data System (ADS)

The Marco Polo NEO sample return M-class mission has been selected for assessment study within the ESA Cosmic Vision 2015-2025 program. The Marco Polo mission proposes to do a sample return mission to Near Earth Asteroid. With this mission we have the opportunity to return for study in Earth-based laboratories a direct sample of the earliest record of how our solar system formed. The landing site and sample selection will be the most important scientific decision to make during the course of the entire mission. The imaging spectrometer is a key instrument being capable to characterize the mineralogical composition of the entire asteroid and to analyze the of the landing site and the returned sample in its own native environment. SETA is a Hyperspectral Imaging Spectrometer able to perform imaging spectroscopy in the spectral range 400-3300 nm for a complete mapping of the target in order to characterize the mineral properties of the surface. The spectral sampling is of at least 20 nm and the spatial resolution of the order of meter. SETA shall be able to return a detailed determination of the mineralogical composition for the different geologic units as well as the overall surface mineralogy with a spatial resolution of the order of few meters. These compositional characterizations involve the analysis of spectral parameters that are diagnostic of the presence and composition of various mineral species and materials that may be present on the target body. Most of the interesting minerals have electronic and vibrational absorption features in their VIS-NIR reflectance spectra. The SETA design is based on a pushbroom imaging spectrometer operating in the 400-3300 nm range, using a 2D array HgCdTe detector. This kind of instrument allows a simultaneous measurement of a full spectrum taken across the field of view defined by the slit's axis (samples). The second direction (lines) of the hyperspectral image shall be obtained by using the relative motion of the orbiter with respect to the target or by using a scan mirror. The SETA optical concept is mostly inherited from the SIMBIO-SYS/VIHI (Visible Infrared Hyperspectral Imager) imaging spectrometer aboard Bepi Colombo mission but also from other space flying imaging spectrometers, such as VIRTIS (on Rosetta and Venus Express, VIR on DAWN).

de Sanctis, M. Cristina; Filacchione, Gianrico; Capaccioni, Fabrizio; Piccioni, Giuseppe; Ammannito, Eleonora; Capria, M. Teresa; Coradini, Angioletta; Migliorini, Alessandra; Battistelli, Enrico; Preti, Giampaolo

2010-05-01

322

NEREUS Nemertes : embedded mass spectrometer control system  

E-print Network

In this thesis, I present Nemertes System, a software suite to control an embedded autonomous mass spectrometer. I first evaluate previous control systems for the hard- ware and evaluate a set of software design goals. The ...

Champy, Adam Samuel

2005-01-01

323

AVIRIS Spectrometer Maps Total Water Vapor Column  

NASA Technical Reports Server (NTRS)

Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) processes maps of vertical-column abundances of water vapor in atmosphere with good precision and spatial resolution. Maps provide information for meteorology, climatology, and agriculture.

Conel, James E.; Green, Robert O.; Carrere, Veronique; Margolis, Jack S.; Alley, Ronald E.; Vane, Gregg A.; Bruegge, Carol J.; Gary, Bruce L.

1992-01-01

324

Visible spectrometer utilizing organic thin film absorption  

E-print Network

In this thesis, I modeled and developed a spectrometer for the visible wavelength spectrum, based on absorption characteristics of organic thin films. The device uses fundamental principles of linear algebra to reconstruct ...

Tiefenbruck, Laura C. (Laura Christine)

2004-01-01

325

Ultra High Mass Range Mass Spectrometer System  

DOEpatents

Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 10.sup.16 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization/ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization/ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

Reilly, Peter T. A. [Knoxville, TN

2005-12-06

326

The Shuttle Imaging Spectrometer Experiment (SISEX)  

NASA Astrophysics Data System (ADS)

The concept of the imaging spectrometer is becoming established as a major new thrust in remote sensing of the Earth. For several years, JPL has operated the Airborne Imaging Spectrometer on a NASA C-130; this instrument has demonstrated the direct identification of surface materials using imaging spectrometry. An advanced aircraft instrument, the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), began operation on a NASA U-2 in 1987. The Shuttle Imaging Spectrometer Experiment (SISEX) was conceived as the next step in the sequence, and would provide a relatively inexpensive demonstration of the concept in Earth orbit. This paper will describe the design and development status of SISEX, and the status of the enabling technology.

Herring, Mark

1987-01-01

327

The Shuttle Imaging Spectrometer Experiment (SISEX)  

NASA Astrophysics Data System (ADS)

The concept of the imaging spectrometer is becoming established as a major new thrust in remote sensing of the earth. For several years, JPL has operated the airborne imaging spectrometer on a NASA C-130; this instrument has demonstrated the direct identification of surface materials using imaging spectrometry. An advanced aircraft instrument, the airborne visible/infrared imaging spectrometer (AVIRIS), began operation on a NASA U-2 in 1987. The Shuttle Imaging Spectrometer Experiment (SISEX) was conceived as the next step in the sequence, and would provide a relatively inexpensive demonstration of the concept in earth orbit. This paper describes the design and development status of SISEX and the status of the enabling technology.

Herring, Mark

328

The iLocater Doppler Spectrometer  

NASA Astrophysics Data System (ADS)

iLocater is a diffraction-limited planet-hunting spectrometer being developed for the Large Binocular Telescope. In this poster, we present iLocater's science cases and most recent mechanical and optical design.

Bechter, E.; Bechter, A.; Crepp, J. R.; Berg, M.; Carroll, J.; Collins, K.; Corpuz, T.; Ketterer, R.; Kielb, E.; Stoddard, R.; Eisner, J.; Gaudi, B. S.; Hinz, P.; Kratter, K.; Macela, G.; Quirrenbach, A.; Skrutskie, M.; Sozzetti, A.; Woodward, C. E.; Zhao, B.

2014-03-01

329

Imaging Spectrometer on a Chip  

NASA Technical Reports Server (NTRS)

A proposed visible-light imaging spectrometer on a chip would be based on the concept of a heterostructure comprising multiple layers of silicon-based photodetectors interspersed with long-wavelength-pass optical filters. In a typical application, this heterostructure would be replicated in each pixel of an image-detecting integrated circuit of the active-pixel-sensor type (see figure). The design of the heterostructure would exploit the fact that within the visible portion of the spectrum, the characteristic depth of penetration of photons increases with wavelength. Proceeding from the front toward the back, each successive long-wavelength-pass filter would have a longer cutoff wavelength, and each successive photodetector would be made thicker to enable it to absorb a greater proportion of incident longer-wavelength photons. Incident light would pass through the first photodetector and encounter the first filter, which would reflect light having wavelengths shorter than its cutoff wavelength and pass light of longer wavelengths. A large portion of the incident and reflected shorter-wavelength light would be absorbed in the first photodetector. The light that had passed through the first photodetector/filter pair of layers would pass through the second photodetector and encounter the second filter, which would reflect light having wavelengths shorter than its cutoff wavelength while passing light of longer wavelengths. Thus, most of the light reflected by the second filter would lie in the wavelength band between the cutoff wavelengths of the first and second filters. Thus, further, most of the light absorbed in the second photodetector would lie in this wavelength band. In a similar manner, each successive photodetector would detect, predominantly, light in a successively longer wavelength band bounded by the shorter cutoff wavelength of the preceding filter and the longer cutoff wavelength of the following filter.

Wang, Yu; Pain, Bedabrata; Cunningham, Thomas; Zheng, Xinyu

2007-01-01

330

The VERDI fission fragment spectrometer  

NASA Astrophysics Data System (ADS)

The VERDI time-of-flight spectrometer is dedicated to measurements of fission product yields and of prompt neutron emission data. Pre-neutron fission-fragment masses will be determined by the double time-of-flight (TOF) technique. For this purpose an excellent time resolution is required. The time of flight of the fragments will be measured by electrostatic mirrors located near the target and the time signal coming from silicon detectors located at 50 cm on both sides of the target. This configuration, where the stop detector will provide us simultaneously with the kinetic energy of the fragment and timing information, significantly limits energy straggling in comparison to legacy experimental setup where a thin foil was usually used as a stop detector. In order to improve timing resolution, neutron transmutation doped silicon will be used. The high resistivity homogeneity of this material should significantly improve resolution in comparison to standard silicon detectors. Post-neutron fission fragment masses are obtained form the time-of-flight and the energy signal in the silicon detector. As an intermediary step a diamond detector will also be used as start detector located very close to the target. Previous tests have shown that poly-crystalline chemical vapour deposition (pCVD) diamonds provides a coincidence time resolution of 150 ps not allowing complete separation between very low-energy fission fragments, alpha particles and noise. New results from using artificial single-crystal diamonds (sCVD) show similar time resolution as from pCVD diamonds but also sufficiently good energy resolution.

Frégeau, M. O.; Bry?, T.; Gamboni, Th.; Geerts, W.; Oberstedt, S.; Oberstedt, A.; Borcea, R.

2013-12-01

331

Hadamard spectrometer for passive LWIR standoff surveillance  

Microsoft Academic Search

Based on the principle of the Integrated Optical Spectrometer (IOSPEC), a waveguide-based, longwave infrared (LWIR) dispersive spectrometer with multiple input slits for Hadamard spectroscopy was designed and built intended for passive standoff chemical agent detection in 8 to 12mum spectral range. This prototype unit equips with a three-inch input telescope providing a field-of-view of 1.2 degrees, a 16-microslit array (each

Roman V. Kruzelecky; Brian Wong; Jing Zou; Najeeb Mohammad; Wes Jamroz; Mohammed Soltani; Mohamed Chaker; Emile Haddad; Philips Laou; Suzanne Paradis

2007-01-01

332

Compact hydrogen\\/helium isotope mass spectrometer  

Microsoft Academic Search

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,

Herbert O. Funsten; David J. McComas; Earl E. Scime

1996-01-01

333

Ruggedized Spectrometers Are Built for Tough Jobs  

NASA Technical Reports Server (NTRS)

The Mars Curiosity Chemistry and Camera instrument, or ChemCam, analyzes the elemental composition of materials on the Red Planet by using a spectrometer to measure the wavelengths of light they emit. Principal investigator Roger Wiens worked with Ocean Optics, out of Dunedin, Florida, to rework the company's spectrometer to operate in cold and rowdy conditions and also during the stresses of liftoff. Those improvements have been incorporated into the firm's commercial product line.

2015-01-01

334

Optical Calibration For Jefferson Lab HKS Spectrometer  

E-print Network

In order to accept very forward angle scattering particles, Jefferson Lab HKS experiment uses an on-target zero degree dipole magnet. The usual spectrometer optics calibration procedure has to be modified due to this on-target field. This paper describes a new method to calibrate HKS spectrometer system. The simulation of the calibration procedure shows the required resolution can be achieved from initially inaccurate optical description.

L. Yuan; L. Tang

2005-11-04

335

Mass Spectrometer for Airborne Micro-Organisms  

NASA Technical Reports Server (NTRS)

Bacteria and other micro-organisms identified continously with aid of new technique for producing samples for mass spectrometer. Technique generates aerosol of organisms and feeds to spectrometer. Given species of organism produces characteristic set of peaks in mass spectrum and thereby identified. Technique useful for monitoring bacterial makeup in environmental studies and in places where cleanliness is essential, such as hospital operating rooms, breweries, and pharmaceutical plants.

Sinha, M. P.; Friedlander, S. K.

1986-01-01

336

A 4pi dilepton spectrometer: PEPSI  

Microsoft Academic Search

A novel positron-electron pair spectroscopy instrument (PEPSI) was designed to measure transitions in the energy region 10-40 MeV. It consists of Nd2Fe14B permanent magnets forming a compact 4pi magnetic filter consisting of 12 positron and 20 electron mini-orange-like spectrometers. The response function of PEPSI has been measured with mono-energetic beams of electrons from 5 to 20 MeV. The PEPSI spectrometer

A. Buda; J. C. S. Bacelar; A. Balanda; J. van Klinken; Z. Sujkowski; A. van der Woude

1993-01-01

337

Design of a transuranic VUV spectrometer  

SciTech Connect

Most of our present knowledge about the physics of 5f systems derives from studies of uranium and its compounds. This is particularly true in the case of photoemission measurements where the intense radioactivity has prevented studies at synchrotron sources. The development of a transuranic VUV spectrometer capable of safe operation at a synchrotron source would represent a giant step in 5f research. This paper describes the conceptual design of such a spectrometer.

Arko, A.J.

1987-01-01

338

Permanent magnet system of alpha magnetic spectrometer  

Microsoft Academic Search

Alpha magnetic spectrometer (AMS) is the first large magndtic spectrometer in space. Its precursor flioht was completed successfully\\u000a in June 1998. The key part of AMS is the permanent magnet system, which was built by the lnstitute of Electric Engineering,\\u000a the institute of High Energy Physics and the Chinese Academy of Launch Vehicle Technology. This system includes a permanent\\u000a magnet

Hesheng Chen

2000-01-01

339

SUB 1-Millimeter Size Fresnel Micro Spectrometer  

NASA Technical Reports Server (NTRS)

An ultra-small micro spectrometer with less than 1mm diameter was constructed using Fresnel diffraction. The fabricated spectrometer has a diameter of 750 nmicrometers and a focal length of 2.4 mm at 533nm wavelength. The micro spectrometer was built with a simple negative zone plate that has an opaque center with an ecliptic shadow to remove the zero-order direct beam to the aperture slit. Unlike conventional approaches, the detailed optical calculation indicates that the ideal spectral resolution and resolving power do not depend on the miniaturized size but only on the total number of rings. We calculated 2D and 3D photon distribution around the aperture slit and confirmed that improved micro-spectrometers below 1mm size can be built with Fresnel diffraction. The comparison between mathematical simulation and measured data demonstrates the theoretical resolution, measured performance, misalignment effect, and improvement for the sub-1mm Fresnel micro-spectrometer. We suggest the utilization of an array of micro spectrometers for tunable multi-spectral imaging in the ultra violet range.

Park, Yeonjoon; Koch, Laura; Song, Kyo D.; Park, Sangloon; King, Glen; Choi, Sang

2010-01-01

340

A small gas inlet system for orbital mass-spectrometer calibrations  

NASA Technical Reports Server (NTRS)

A gas inlet system is described for generating precise gas pressures that are to be used as calibration references for the mass spectrometers aboard the dual air density Explorer satellites. This gas inlet system was developed as an inflight calibration technique in which a known amount of onboard gas is released in the satellite cavity and is detected by the mass spectrometer. Although several flight mass spectrometer experiments have been proposed, none make use of the inflight calibration technique described in this report. Laboratory measurements and calibration of the metering leak technique for the gas inlet systems are discussed. The systems tested have metering leak rates between 2 and 4 microliters/sec at 298 K for argon-40, and they produce molecular flow up to 100 torr, which is the highest test pressure in this experiment. Test data show that metering leak rates are reproducible within 1 percent of established means for helium-3, helium-4, and argon-40.

Smith, A.; Stell, R. E.

1978-01-01

341

Azimuthal anisotropy of charged particles from multiparticle correlations in pPb and PbPb collisions with CMS  

NASA Astrophysics Data System (ADS)

Motivated by two- and four-particle azimuthal correlation measurements that suggest possible collective flow for charged particles emitted in pPb collisions at ?{sNN} = 5.02 TeV, we extend the correlation results for these collisions using the six- and eight-particle cumulant methods, and the Lee-Yang Zeros method. CMS has an extensive program studying azimuthal harmonic coefficients for both PbPb and pPb collisions using various methods. The current pPb results will be presented in this context. The data were collected by the CMS experiment at the LHC using both minimum bias and high-multiplicity collision triggers over a wide range in pseudorapidity. The results are compared to 2.76 TeV semi-peripheral PbPb collision data collected in 2011 covering a similar range of particle multiplicities. The second-order azimuthal anisotropy Fourier harmonic (v2) is shown for the different methods. A comparison of the six- and greater particle correlations to the previously published two- and four-particle correlation results sheds light on the multiparticle nature of the azimuthal anisotropy. The results are also discussed in terms of recent calculations that explore the role of participant fluctuations on measurements of higher-order particle correlations in pPb collisions.

Wang, Quan

2014-11-01

342

Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider  

E-print Network

Measurements of multi-particle azimuthal correlations (cumulants) for charged particles in p-Pb and Pb-Pb collisions are presented. They help address the question of whether there is evidence for global, flow-like, azimuthal correlations in the p-Pb system. Comparisons are made to measurements from the larger Pb-Pb system, where such evidence is established. In particular, the second harmonic two-particle cumulants are found to decrease with multiplicity, characteristic of a dominance of few-particle correlations in p-Pb collisions. However, when a $|\\Delta \\eta|$ gap is placed to suppress such correlations, the two-particle cumulants begin to rise at high-multiplicity, indicating the presence of global azimuthal correlations. The Pb-Pb values are higher than the p-Pb values at similar multiplicities. In both systems, the second harmonic four-particle cumulants exhibit a transition from positive to negative values when the multiplicity increases. The negative values allow for a measurement of $v_{2}\\{4\\}$ to be made, which is found to be higher in Pb-Pb collisions at similar multiplicities. The second harmonic six-particle cumulants are also found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find $v_{2}\\{4\\} \\simeq v_{2}\\{6\\}\

ALICE Collaboration

2014-10-28

343

Panoramic Imaging Spectroscopy with the Ultra Compact Imaging Spectrometer (UCIS)  

NASA Astrophysics Data System (ADS)

In Situ imaging spectroscopy provides a way to address complex questions of geological evolution for aqueous, volcanic, and impact processes by mapping mineral composition at the spatial scale of rocks and outcrops. Spectroscopy from 500-2600 nm is an established technique for measuring the mineralogy of sedimentary and igneous rocks, outcrops, and regoliths. Minerals such as olivine, pyroxene, carbonates, clays, and sulfates exhibit absorption features that are highly diagnostic of their structure and composition in this wavelength range. Imaging spectroscopy allows for mineralogy to be mapped at geological important special scales thus allowing for the investigation of the spatial relationship between minerals and compositions and of the geologic and geochemical processes of planets, asteroids, comets, and moons. The Ultra Compact Imaging Spectrometer (UCIS) is a JPL developed imaging spectrometer suitable for inclusion on a Mars or lunar rover or asteroid lander but packaged for operation at terrestrial ambient conditions. UCIS is an Offner spectrometer using JPL e-beam gratings, HgCdTe detectors with many components having direct heritage from the Moon Mineralogy Mapper (M3). UCIS covers the wavelength range from 500-2600 nm with 10 nm sampling/resolution with a 30 deg. field of view with and instantaneous field of view 1.4 mrad (spatial sampling of 4.2 mm at 3 m.) The optical head of the instrument has a mass of < 2 kg on the mass and takes 5.2 W of power (Van Gorp et al. 2011). The instrument has completed calibration and has begun field trials. Initial trials were carried out in the JPL "Mars Yard" robotic testbed. The Mars Yard contains a large number of basaltic boulders and other rocks/soils. Additional rocks and spectrally interesting materials were place in the Mars Yard to fully assess the ability of the instrument to identify spectrally distinct material. To collect data the instrument was mounted with the spectrometer slit oriented in elevation on a precision controlled stage. The slit was then scanned in azimuth to build up a spatial image. Telluric absorption features were calibrated out using Spectralon® calibration target taken before and after the scan of the Mars Yard. Spectra of selected materials in the Mars Yard were collected with an Analytical Spectral Devices Field Spectrometer to compare to the UCIS spectrometer. Initial results show clear spectral features consistent with the mineralogies present. Additional field trials are planned in September in geologically interesting locations. Reference: Van Gorp et al., Optical design and performance of the Ultra-Compact Imaging Spectrometer, SPIE Optics and Photonics, San Diego, Aug 21-25, 2011. Acknowledgements: This work has been conducted at the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration. Work was carried out with JPL Research and Technology Development Funding. False color (RGB) image reconstruction of part of the Mars Yard Panorma

Blaney, D. L.; Mouroulis, P.; Van Gorp, B.; Green, R. O.; Borden, M.; Smith-Dryden, S. D.; Bender, H.; Sellar, R. G.; Rodriguez, J.; Wilson, D.

2012-12-01

344

Development and Characterization of a High Resolution Portable Gamma Spectrometer  

NASA Astrophysics Data System (ADS)

The recent disaster of Fukushima in Japan combined with the high demand to enhance nuclear safety and to minimize personal exposure to radioactive materials has a significant impact on research and development of radiation detection instrumentation. Currently, there is ample effort worldwide in the pursuit of radiation detection to maximize the accuracy and meet international standards in terms of size and specifications to enable radiation protection decision making. Among the requirements is the development of a portable, light-weight gamma-ray isotope identifier to be used by first responders in nuclear accidents as well as for radiation security and identification of illicit material isotopes. From nuclear security perspective, research into advanced screening technologies has become a high priority in all aspects, while for occupational safety, and environmental radiation protection, the regulatory authorities are requiring specific performance of radiation detection and measuring devices. At the applied radiation laboratory of the University of Ontario Institute of Technology, UOIT, the development of a high resolution spectrometer for medium and high energy gamma ray has been conducted. The spectrometer used a newly developed scintillator based on a LaBr3(Ce) crystal. The detector has been modeled using advanced Monte Carlo code (MCNP/X code) for the response function simulation and parameter characterization. The simulation results have been validated by experimental investigations using a wide range of gamma radiation energies. The developed spectrometer has been characterized in terms of resolution and response in different fields. It has also been compared with other crystals such as NaI(TI) and LiI(Eu).

Ali, Muhammad

345

IR Spectrometer Using 90-degree Off-axis Parabolic Mirrors  

SciTech Connect

A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light ource at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output IR recording camera. With an initial wavelength range of 1500–4500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors, serves as the dispersion element. The spectrometer is doubly telecentric. With proper choice of the air spacing between the prism and the second parabolic mirror, any spectral region of interest within the InSb camera array’s sensitivity region can be recorded. The wavelengths leaving the second parabolic mirror are collimated, thereby relaxing the camera positioning tolerance. To set up the instrument, two different wavelength (visible) lasers are introduced at the entrance slit and made collinear with the optical axis via flip mirrors. After dispersion by the prism, these two laser beams are directed to tick marks located on the outside housing of the gated IR camera. This provides first-order wavelength calibration for the instrument. Light that is reflected off the front prism face is coupled into a high-speed detector to verify steady radiance during the gated spectral imaging. Alignment features include tick marks on the prism and parabolic mirrors. This instrument was designed to complement singlepoint pyrometry, which provides continuous time histories of a small collection of spots from shock-heated targets.

Robert M. Malone, Richard, G. Hacking, Ian J. McKenna, and Daniel H. Dolan

2008-09-02

346

IR Spectrometer Using 90-Degree Off-Axis Parabolic Mirrors  

SciTech Connect

A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light Source at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output recording camera. With an initial wavelength range of 1500–4500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors, serves as the dispersion element. The spectrometer is doubly telecentric. With proper choice of the air spacing between the prism and the second parabolic mirror, any spectral region of interest within the InSb camera array’s sensitivity region can be recorded. The wavelengths leaving the second parabolic mirror are collimated, thereby relaxing the camera positioning tolerance. To set up the instrument, two different wavelength (visible) lasers are introduced at the entrance slit and made collinear with the optical axis via flip mirrors. After dispersion by the prism, these two laser beams are directed to tick marks located on the outside housing of the gated IR camera. This provides first-order wavelength calibration for the instrument. Light that is reflected off the front prism face is coupled into a high-speed detector to verify steady radiance during the gated spectral imaging. Alignment features include tick marks on the prism and parabolic mirrors. This instrument was designed to complement single-point pyrometry, which provides continuous time histories of a small collection of spots from shock-heated targets.

Robert M. Malone, Ian J. McKenna

2008-03-01

347

Mobility Spectrometer Studies on Hydrazine and Ammonia Detection  

NASA Technical Reports Server (NTRS)

An airborne vapor analyzer for detecting sub- to low- parts-per-million (ppm) hydrazine in the presence of higher concentration levels of ammonia has been under development for the Orion program. The detector is based on ambient pressure ionization and ion mobility characterization. The detector encompasses: 1) a membrane inlet to exclude particulate and aerosols from the analyzer inlet; 2) a method to separate hydrazine from ammonia which would otherwise lead to loss of calibration and quantitative accuracy for the hydrazine determination; and 3) response and quantitative determinations for both hydrazine and ammonia. Laboratory studies were made to explore some of these features including mobility measurements mindful of power, size, and weight issues. The study recommended the use of a mobility spectrometer of traditional design with a reagent gas and equipped with an inlet transfer line of bonded phase fused silica tube. The inlet transfer line provided gas phase separation of neutrals of ammonia from hydrazine at 50 C simplifying significantly the ionization chemistry that underlies response in a mobility spectrometer. Performance of the analyzer was acceptable between ranges of 30 to 80 C for both the pre-fractionation column and the drift tube. An inlet comprised of a combined membrane with valve-less injector allowed high speed quantitative determination of ammonia and hydrazine without cross reactivity from common metabolites such as alcohols, esters, and aldehydes. Preliminary test results and some of the design features are discussed.

Niu, William; Eiceman, Gary; Szumlas, Andrew; Lewis, John

2011-01-01

348

Proceedings of the Airborne Imaging Spectrometer Data Analysis Workshop  

NASA Technical Reports Server (NTRS)

The Airborne Imaging Spectrometer (AIS) Data Analysis Workshop was held at the Jet Propulsion Laboratory on April 8 to 10, 1985. It was attended by 92 people who heard reports on 30 investigations currently under way using AIS data that have been collected over the past two years. Written summaries of 27 of the presentations are in these Proceedings. Many of the results presented at the Workshop are preliminary because most investigators have been working with this fundamentally new type of data for only a relatively short time. Nevertheless, several conclusions can be drawn from the Workshop presentations concerning the value of imaging spectrometry to Earth remote sensing. First, work with AIS has shown that direct identification of minerals through high spectral resolution imaging is a reality for a wide range of materials and geological settings. Second, there are strong indications that high spectral resolution remote sensing will enhance the ability to map vegetation species. There are also good indications that imaging spectrometry will be useful for biochemical studies of vegetation. Finally, there are a number of new data analysis techniques under development which should lead to more efficient and complete information extraction from imaging spectrometer data. The results of the Workshop indicate that as experience is gained with this new class of data, and as new analysis methodologies are developed and applied, the value of imaging spectrometry should increase.

Vane, G. (editor); Goetz, A. F. H. (editor)

1985-01-01

349

Variable filter array spectrometer of VPD PbSe  

NASA Astrophysics Data System (ADS)

MWIR spectroscopy shows a large potential in the current IR devices market, due to its multiple applications (gas detection, chemical analysis, industrial monitoring, combustion and flame characterization, food packaging etc) and its outstanding performance (good sensitivity, NDT method, velocity of response, among others), opening this technique to very diverse fields of application, such as industrial monitoring and control, agriculture, medicine and environmental monitoring. However, even though a big interest on MWIR spectroscopy technique has been present in the last years, two major barriers have held it back from its widespread use outside the laboratory: the complexity and delicateness of some popular techniques such as Fourier-transform IR (FT-IR) spectrometers, and the lack of affordable specific key elements such a MWIR light sources and low cost (real uncooled) detectors. Recent developments in electrooptical components are helping to overcome these drawbacks. The need for simpler solutions for analytical measurements has prompted the development of better and more affordable uncooled MWIR detectors, electronics and optics. In this paper a new MWIR spectrometry device is presented. Based on linear arrays of different geometries (64, 128 and 256 elements), NIT has developed a MWIR Variable Filter Array Spectrometer (VFAS). This compact device, with no moving parts, based on a rugged and affordable detector, is suitable to be used in applications which demand high sensitivity, good spectral discrimination, reliability and compactness, and where an alternative to the traditional scanning instrument is desired. Some measurements carried out for several industries will be also presented.

Linares-Herrero, R.; Vergara, G.; Gutiérrez-Álvarez, R.; Fernández-Montojo, C.; Gómez, L. J.; Villamayor, V.; Baldasano-Ramírez, A.; Montojo, M. T.

2012-06-01

350

Bulk and integrated acousto-optic spectrometers for molecular astronomy with heterodyne spectrometers  

NASA Technical Reports Server (NTRS)

A survey of acousto-optic spectrometers for molecular astronomy is presented, noting a technique of combining the acoustic bending of a collimated coherent light beam with a Bragg cell followed by an array of sensitive photodetectors. This acousto-optic spectrometer has a large bandwidth, a large number of channels, high resolution, and is energy efficient. Receiver development has concentrated on high-frequency heterodyne systems for the study of the chemical composition of the interstellar medium. RF spectrometers employing acousto-optic diffraction cells are described. Acousto-optic techniques have been suggested for applications to electronic warfare, electronic countermeasures and electronic support systems. Plans to use integrated optics for the further miniaturization of acousto-optic spectrometers are described. Bulk acousto-optic spectrometers with 300 MHz and 1 GHz bandwidths are being developed for use in the back-end of high-frequency heterodyne receivers for astronomical research.

Chin, G.; Buhl, D.; Florez, J. M.

1981-01-01

351

A Wideband Spectrometer with RFI Detection  

NASA Astrophysics Data System (ADS)

We report on the design and construction of a wideband spectrometer of 500 MHz instantaneous bandwidth that includes automatic radio frequency interference (RFI) detection. The implementation is based on hardware developed at the Center for Astronomical Signal Processing and Electronics Research (CASPER). The unique aspect of the spectrometer is that it accumulates both power and power-squared, which are then used to develop a spectral kurtosis (SK) estimator. The SK estimator statistics are used for real-time detection and excision of certain types of RFI embedded in the received signal. We report on the use of this spectrometer in the Korean Solar Radio Burst Locator (KSRBL). This instrument utilizes four of these 500 MHz bandwidth SK spectrometers in parallel, to achieve a 2 GHz instantaneous bandwidth that is time multiplexed over the entire 0.24-18 GHz radio frequency range, to study solar bursts. The performance of the spectrometers for excising RFI over this range is presented. It is found that the algorithm is especially useful for excising highly intermittent RFI but is less successful for RFI due to digital signals. A method we call multiscale SK is presented that addresses the known blindness of Kurtosis-based estimators to 50% duty-cycle RFI. The SK algorithm can also be applied to spectral channels prior to correlation to remove unwanted RFI from interferometer data.

Gary, Dale E.; Liu, Zhiwei; Nita, Gelu M.

2010-05-01

352

Imaging Spectrometers Using Concave Holographic Gratings  

NASA Technical Reports Server (NTRS)

Imaging spectroscopy combines the spatial attributes of imaging with the compositionally diagnostic attributes of spectroscopy. For spacebased remote sensing applications, mass, size, power, data rate, and application constrain the scanning approach. For the first three approaches, substantial savings in mass and size of the spectrometer can be achieved in some cases with a concave holographic grating and careful placement of an order-sorting filter. A hologram etched on the single concave surface contains the equivalent of the collimating, dispersing, and camera optics of a conventional grating spectrometer and provides substantial wavelength dependent corrections for spherical aberrations and a flat focal field. These gratings can be blazed to improve efficiency when used over a small wavelength range or left unblazed for broadband uniform efficiency when used over a wavelength range of up to 2 orders. More than 1 order can be imaged along the dispersion axis by placing an appropriately designed step order-sorting filter in front of the one- or two-dimensional detector. This filter can be shaped for additional aberration corrections. The VIRIS imaging spectrometer based on the broadband design provides simultaneous imaging of the entrance slit from lambda = 0.9 to 2.6 microns (1.5 orders) onto a 128 x 128 HgCdTe detector (at 77 K). The VIRIS spectrometer was used for lunar mapping with the UH 24.in telescope at Mauna Kea Observatory. The design is adaptable for small, low mass, space based imaging spectrometers.

Gradie, J.; Wang, S.

1993-01-01

353

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

2012-05-04

354

A portable spectrometer for use from 5 to 15 micrometers  

NASA Technical Reports Server (NTRS)

A field portable spectrometer suitable for collecting data relevant to remote sensing applications in the 8 to 12 micrometer atmospheric window has been built at the Jet Propulsion Laboratory. The instrument employs a single cooled HgCdTe detector and a continuously variable filter wheel analyzer. The spectral range covered is 5 to 14.5 micrometers and the resolution is approximately 1.5 percent of the wavelength. A description of the hardware is followed by a discussion of the analysis of the spectral data leading to finished emissivity and radiance spectra. A section is devoted to the evaluation of the instrument performance with respect to spectral resolution, radiometric precision, and accuracy. Several examples of spectra acquired in the field are included.

Hoover, G.; Kahle, A. B.

1986-01-01

355

An Overview of the LADEE Ultraviolet-Visible Spectrometer  

NASA Astrophysics Data System (ADS)

The Ultraviolet-Visible Spectrometer (UVS) instrument, which flew on the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft (SC), was one of three science instruments used to characterize the lunar exosphere. UVS is a point spectrograph operating between 230-810 nm and used its two optical apertures to make observations of the exosphere just above the surface at a range of local times and altitudes, as well as making solar occultation measurements at the lunar sunrise terminator. The instrument was led out of NASA Ames Research Center with primary hardware being provided by Draper Laboratories. Final instrument integration, testing and operations were performed at NASA Ames. Over the course of the 140-day LADEE mission UVS acquired more than 1 million spectra, providing a unique data set for lunar exosphere gasses and dust.

Colaprete, Anthony; Vargo, Kara; Shirley, Mark; Landis, Dave; Wooden, Diane; Karcz, John; Hermalyn, Brendan; Cook, Amanda

2014-12-01

356

Polarization analysis for the thermal chopper spectrometer TOPAS  

NASA Astrophysics Data System (ADS)

We report on the progress of the construction of the thermal time-of-flight spectrometer with polarization analysis TOPAS at the Mayer-Leibnitz Zentrum (MLZ). The instrument components approach the status to be ready for installation. The special feature of the instrument is its capability for wide-angle polarization analysis in the thermal spectral range. Here we describe a novel approach to rotate the neutron spin adiabatically into the X, Y or Z direction of the laboratory frame by combination of permanent magnets aligned as Halbach rings and electrically generated fields. Despite the severe spatial restrictions the design exhibits a very high adiabaticity and interacts only weakly with the coil layout for the analyzing 3He spin filter cell (SFC).

Voigt, Jörg; Soltner, Helmut; Babcock, Earl; Aldus, Robert J.; Salhi, Zahir; Gainov, Ramil R.; Brückel, Thomas

2015-01-01

357

Portable instant display and analysis reflectance spectrometer  

NASA Technical Reports Server (NTRS)

A portable analysis spectrometer (10) for field mineral identification is coupled to a microprocessor (11) and memory (12) through a bus (13) and A/D converter (14) to display (16) a spectrum of reflected radiation in a band selected by an adjustable band spectrometer (20) and filter (23). A detector array (21) provides output signals at spaced frequencies within the selected spectrometer band which are simultaneously converted to digital form for display. The spectrum displayed is compared with a collection of spectra for known minerals. That collection is stored in memory and selectively displayed with the measured spectrum, or stored in a separate portfolio. In either case, visual comparison is made. Alternatively, the microprocessor may use an algorithm to make the comparisons in search for the best match of the measured spectrum with one of the stored spectra to identify the mineral in the target area.

Goetz, Alexander F. H. (Inventor)

1985-01-01

358

Compact hydrogen/helium isotope mass spectrometer  

DOEpatents

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)

1996-01-01

359

Testing of Josephson Spectrometer with Waveguide Coupling  

NASA Astrophysics Data System (ADS)

One of the challenges in public security is the quick and reliable identification of threat liquids in bottles, when vapour analysis is not possible. Recently, we demonstrated that it is possible to rapidly identify liquids by EM measurements of their dielectric functions in the sub-THz range with a high-Tc Josephson spectrometer. Following this approach, we have developed a Josephson spectrometer with a new radiation coupling system, based on dielectric waveguides. In this paper, we present the results of spectroscopic measurements on liquid samples of various purities including 30% H2O2/H2O, performed using our Josephson spectrometer with waveguide coupling. Also, the signal and noise characteristics of a classical Josephson detector used in our liquid identifier were numerically simulated and the power dynamic range was estimated for a wide spread of junction parameters.

Lyatti, M.; Gundareva, I.; Pavlovskii, V.; Poppe, U.; Divin, Y.

2014-05-01

360

Calibration of a Flat Field Soft X-ray Grating Spectrometer for Laser Produced Plasmas  

SciTech Connect

We have calibrated the x ray response of a variable line spaced grating spectrometer, known as the VSG, at the Fusion and Astrophysics Data and Diagnostic Calibration Facility at the Lawrence Livermore National Laboratory (LLNL). The VSG has been developed to diagnose laser produced plasmas, such as those created at the Jupiter Laser Facility and the National Ignition Facility at LLNL, and at both the Omega and Omega EP lasers at University of Rochester's Laboratory for Laser Energetics. The bandwidth of the VSG spans the range from {approx} 6 to 60 {angstrom}. The calibration results present here include the VSG's dispersion and quantum efficiency. The dispersion is determined by measuring the x rays emitted from hydrogen-like and helium-like ions of carbon, nitrogen, oxygen, neon, and aluminum. The quantum efficiency is calibrated to an accuracy of 30% or better by normalizing the x ray intensities recorded by the VSG to those simultaneously recorded by an x ray microcalorimeter spectrometer.

Park, J; Brown, G V; Schneider, M B; Baldis, H A; Beiersdorfer, P; Cone, K V; Kelley, R L; Kilbourne, C A; Magee, E; May, M J; Porter, F S

2010-05-12

361

Degradation Free Spectrometers for Solar EUV Measurements  

NASA Astrophysics Data System (ADS)

Solar EUV observations will be made using two new degradation-free EUV spectrometers on a sounding rocket flight scheduled for summer 2012. The two instruments, a rare gas photoionization-based Optics-Free Spectrometer (OFS) and a Dual Grating Spectrometer (DGS), are filter-free and optics-free. OFS can measure the solar EUV spectrum with a spectral resolution comparable to that of grating-based EUV spectrometers. The DGS selectable spectral bandwidth is designed to provide solar irradiance in a 10 nm band centered on the Lyman-alpha 121.6 nm line and a 4 nm band centered on the He-II 30.4 nm line to overlap EUV observations from the SDO/EUV Variability Experiment (EVE) and the SOHO/Solar EUV Monitor (SEM). A clone of the SOHO/SEM flight instrument and a Rare Gas Ionization Cell (RGIC) absolute EUV detector will also be flown to provide additional measurements for inter-comparison. Program delays related to the sounding rocket flight termination system, which was no longer approved by the White Sands Missile Range prevented the previously scheduled summer 2011 launch of these instruments. During this delay several enhancements have been made to the sounding rocket versions of the DFS instruments, including a lighter, simplified vacuum housing and gas system for the OFS and an improved mounting for the DGS, which allows more accurate co-alignment of the optical axes of the DGS, OFS, and the SOHO/SEM clone. Details of these enhancements and results from additional lab testing of the instruments are reported here. The spectrometers are being developed and demonstrated as part of the Degradation Free Spectrometers (DFS) project under NASA's Low Cost Access to Space (LCAS) program and are supported by NASA Grant NNX08BA12G.

Wieman, S. R.; Didkovsky, L. V.; Judge, D. L.; McMullin, D. R.

2011-12-01

362

Noiseless coding for the Gamma Ray spectrometer  

NASA Technical Reports Server (NTRS)

The payload of several future unmanned space missions will include a sophisticated gamma ray spectrometer. Severely constrained data rates during certain portions of these missions could limit the possible science return from this instrument. This report investigates the application of universal noiseless coding techniques to represent gamma ray spectrometer data more efficiently without any loss in data integrity. Performance results demonstrate compression factors from 2.5:1 to 20:1 in comparison to a standard representation. Feasibility was also demonstrated by implementing a microprocessor breadboard coder/decoder using an Intel 8086 processor.

Rice, R.; Lee, J. J.

1985-01-01

363

Compact Raman Spectrometers Would Detect Hydrogen  

NASA Technical Reports Server (NTRS)

Compact Raman spectrometers developed to measure concentrations of hydrogen as low as hundreds of parts per million in air, nitrogen, or other carrier gases. Advantages include speed, dynamic range, and ease of calibration. Design concept incorporates Raman-scattering apparatus into compact instrument of hydrogen leaking into stream of gas or into gas enclosed in small space. Should hydrogen-fueled cars and trucks come into widespread use, instruments used to detect leaks from vehicles and supply equipment, to help prevent explosions. Similar spectrometers developed to detect other gases emitting characteristic Raman spectra.

Helms, William R.; Adler-Golden, Steven

1993-01-01

364

The BTeV main spectrometer  

NASA Astrophysics Data System (ADS)

BTeV is a second generation B-factory experiment that will use a double-arm, forward spectrometer in the C0 experimental hall at the Fermilab Tevatron. I will describe the motivation and design of the "main spectrometer", consisting of a ring-imaging Cherenkov system for charged particle identification, an electromagnetic calorimeter of lead-tungstate crystals, a proportional tube muon system with magnetized filtering steel, and a straw-tube and silicon strip charged particle tracking system. The vertex system and trigger, as well as the physics motivations for BTeV, are described elsewhere in these proceedings.

Sheldon, Paul D.

2001-04-01

365

The Mass Spectrometer - How It Works  

NSDL National Science Digital Library

This website includes a simple description of how a mass spectrometer works. Mass spectrometry (MS) is an analytical technique for the determination of the elemental composition of a sample or molecule. It is also used for elucidating the chemical structures of molecules, such as peptides and other chemical compounds. The MS principle consists of ionizing chemical compounds to generate charged molecules or molecule fragments and measurement of their mass-to-charge ratios. Keywords: mass spectrometer, mass spectrometry, mass spectrum, mass spectra, spectrum, spectra, mass, ionisation, acceleration, deflection, detection

Clark, Jim

366

Compact Imaging Spectrometer Utilizing Immersed Gratings  

DOEpatents

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

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

2006-03-21

367

A multichannel magneto-chiral dichroism spectrometer  

NASA Astrophysics Data System (ADS)

In this work, we describe a multichannel magneto-chiral dichroism spectrometer for the visible and near infrared wavelength ranges. The optical signal acquisition is based on commercially available Czerny-Turner spectrograph systems equipped with solid state detector arrays. The signal analysis method is based on post-processing phase sensitive detection, where the optical properties of the sample are modulated by an alternating external magnetic field. As an illustration of the performance of this spectrometer, magneto-chiral dichroism was measured in crystals of ? - NiSO4 . 6H2O and good agreement with literature results was obtained.

Kopnov, G.; Rikken, G. L. J. A.

2014-05-01

368

Wide size range fast integrated mobility spectrometer  

DOEpatents

A mobility spectrometer to measure a nanometer particle size distribution is disclosed. The mobility spectrometer includes a conduit and a detector. The conduit is configured to receive and provide fluid communication of a fluid stream having a charged nanometer particle mixture. The conduit includes a separator section configured to generate an electrical field of two dimensions transverse to a dimension associated with the flow of the charged nanometer particle mixture through the separator section to spatially separate charged nanometer particles of the charged nanometer particle mixture in said two dimensions. The detector is disposed downstream of the conduit to detect concentration and position of the spatially-separated nanometer particles.

Wang, Jian

2013-10-29

369

Improved real-time imaging spectrometer  

NASA Technical Reports Server (NTRS)

An improved AOTF-based imaging spectrometer that offers several advantages over prior art AOTF imaging spectrometers is presented. The ability to electronically set the bandpass wavelength provides observational flexibility. Various improvements in optical architecture provide simplified magnification variability, improved image resolution and light throughput efficiency and reduced sensitivity to ambient light. Two embodiments of the invention are: (1) operation in the visible/near-infrared domain of wavelength range 0.48 to 0.76 microns; and (2) infrared configuration which operates in the wavelength range of 1.2 to 2.5 microns.

Lambert, James L. (inventor); Chao, Tien-Hsin (inventor); Yu, Jeffrey W. (inventor); Cheng, Li-Jen (inventor)

1993-01-01

370

Construction of Ibaraki prefectural neutron spectrometers  

NASA Astrophysics Data System (ADS)

Ibaraki Prefectural Government established Science Frontier 21 Initiative (SF21) in 2001. In SF21 the active co-operations between Tsukuba, Tokai and Hitachi areas are accelerated and two Prefecture's neutron spectrometers have been constructed in order to establish the advanced industrial zone by setting the J-PARC as a key component. In addition, the industrial applications of neutron will be promoted. The objectives of SF21 are promotion of industrial applications of J-PARC, grow-up of neutron research scientists, and establishment of infrastructure supporting international collaboration. In this paper, outline of the two Ibaraki prefecture's spectrometers are described.

Hayashi, Makoto; Ishigaki, Toru; Kamiyama, Takashi; Tanaka, Ichiro

2009-02-01

371

Vacuum system for the SAMURAI spectrometer  

NASA Astrophysics Data System (ADS)

The first commissioning experiment of the SAMURAI spectrometer and its beam line was performed in March, 2012. The vacuum system for the SAMURAI spectrometer includes its beam line and the SAMURAI vacuum chamber with the windows for detecting neutrons and charged particles. The window for neutrons was made of stainless steel with a thickness of 3 mm and was designed with a shape of partial cylinder to support itself against the atmospheric pressure. The window for charged particles was of the combination of Kevlar and Mylar with the thickness of 280 and 75 ?m, respectively. The pressure in the vacuum system was at a few Pa throughout the commissioning experiment.

Shimizu, Y.; Otsu, H.; Kobayashi, T.; Kubo, T.; Motobayashi, T.; Sato, H.; Yoneda, K.

2013-12-01

372

NEAR Gamma Ray Spectrometer Characterization and Repair  

NASA Technical Reports Server (NTRS)

This report covers the work completed in the third year of the contract. The principle activities during this period were (1) the characterization of the NEAR 2 Gamma Ray Spectrometer using a neutron generator to generate complex gamma ray spectra and a large Ge Detecter to identify all the major peaks in the spectra; (2) the evaluation and repair of the Engineering Model Unit of the Gamma Ray Spectrometer for the NEAR mission; (3) the investigation of polycapillary x-ray optics for x-ray detection; and (4) technology transfer from NASA to forensic science.

Groves, Joel Lee; Vajda, Stefan

1998-01-01

373

Turning Laboratory \\  

Microsoft Academic Search

Sometimes, a student laboratory exercise will fail. Our normal approach to such an event is to work to prevent its occurrence. Students frequently get frustrated when laboratory results differ from their expectations, and instructors may be embarrassed, disappointed, or even panic-stricken by the outcomes. Laboratory failures can provide excellent learning opportunities for students, however, if they are handled properly. Unexpected

L. Brent Jenkins

374

Peptide sequencing using MALDI on time-of-flight and ion trap mass spectrometers  

Microsoft Academic Search

Two instruments have been developed in our laboratory for the direct amino-acid sequencing of peptides. The first is a time-of-flight (TOF) mass spectrometer that utilizes a coaxial, curved-field reflectron which provides simultaneous focusing of product ins formed by post- source decay (PSD) and obviates the need for scanning or stepping the reflectron voltage. The second is a matrix-assisted laser desorption\\/ionization

Robert J. Cotter; Timothy J. Cornish; Marcela Cordero; Vladimir M. Doroshenko

1996-01-01

375

Validation of Tropospheric Emission Spectrometer (TES) nadir ozone profiles using ozonesonde measurements  

Microsoft Academic Search

We compare Tropospheric Emission Spectrometer (TES) version 2 (V002) nadir ozone profiles with ozonesonde profiles from the Intercontinental Chemical Transport Experiment Ozonesonde Network Study, the World Ozone and Ultraviolet Data Center, the Global Monitoring Division of the Earth System Research Laboratory, and the Southern Hemisphere Additional Ozonesonde archives. Approximately 1600 coincidences spanning 72.5°S-80.3°N from October 2004 to October 2006 are

Ray Nassar; Jennifer A. Logan; Helen M. Worden; Inna A. Megretskaia; Kevin W. Bowman; Gregory B. Osterman; Anne M. Thompson; David W. Tarasick; Shermane Austin; Hans Claude; Manvendra K. Dubey; Wayne K. Hocking; Bryan J. Johnson; Everette Joseph; John Merrill; Gary A. Morris; Mike Newchurch; Samuel J. Oltmans; Françoise Posny; F. J. Schmidlin; Holger Vömel; David N. Whiteman; Jacquelyn C. Witte

2008-01-01

376

High-energy resolution Thomson Parabola spectrometer for laser plasma diagnostics  

SciTech Connect

Thomson Parabola (TP) spectrometers are widely used devices for laser-driven beam diagnostics as they provide a complete set of information on the accelerated particles. A novel TP has been developed at LNS with a design able to detect protons up to 20 MeV. The layout design and some results obtained during the experimental campaign at PALS laboratory will be reported in the following.

Cirrone, G. A. P.; Schillaci, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic)] [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Carpinelli, M. [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy)] [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy); Cuttone, G.; Romano, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy)] [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Maggiore, M. [Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague, Czech Republic and Laboratori Nazionali di Legnaro, INFN, Via Università 2, Legnaro (PD) (Italy)] [Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague, Czech Republic and Laboratori Nazionali di Legnaro, INFN, Via Università 2, Legnaro (PD) (Italy); Ter-Avetisyan, S. [Laboratori Nazionali di Legnaro, INFN, Via Università 2, Legnaro (PD) (Italy)] [Laboratori Nazionali di Legnaro, INFN, Via Università 2, Legnaro (PD) (Italy); Tramontana, A. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and School of Mathematics and Physics, The Queen's University Belfast, BT7 1NN (United Kingdom)] [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and School of Mathematics and Physics, The Queen's University Belfast, BT7 1NN (United Kingdom); Velyhan, A. [Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic)] [Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic)

2013-07-26

377

JPL Carbon Dioxide Laser Absorption Spectrometer Data Processing Results for the 2010 Flight Campaign  

NASA Technical Reports Server (NTRS)

As a precursor to and validation of the core technology necessary for NASA's Active Sensing of CO2 Emissions over Nights, Days,and Seasons (ASCENDS) mission, we flew JPL's Carbon Dioxide Laser Absorption Spectrometer (CO2LAS) in a campaign of five flights onboard NASA's DC-8 Airborne Laboratory in July 2010. This is the latest in a series of annual flight campaigns that began in 2006, and our first on the DC-8 aircraft.

Jacob, Joseph C.; Spiers, Gary D.; Menzie, Robert T.; Christensen, Lance E.

2011-01-01

378

Scene-based spectral response function shape discernibility for the APEX imaging spectrometer  

Microsoft Academic Search

Scene-based spectrometer calibration is becoming increasingly interesting due to the decreasing cost of computing resources as compared with laboratory calibration costs. Three of the most important instrument parameters needed for deriving surface reflectance products are per-band bandwidths, i.e., full-width at half-maximum, band centers, and spectral response function (SRF) shape. Methods for scene-based bandwidth and band center retrieval based on curve

Jason Brazile; Robert A. Neville; Karl Staenz; Daniel Schläpfer; Lixin Sun; Klaus I. Itten

2006-01-01

379

Simulation of background characteristics of low-level gamma-ray spectrometers using Monte Carlo method.  

PubMed

A computing code based on the CERN's GEANT4 has been used to compute cosmic-ray background components of low-level Ge-spectrometers, optionally equipped with an anticosmic shield made of a plastic scintillation detector. The results show that the background of the Ge detector placed at 100 m w.e. (water equivalent) has decreased by a factor of 30 and 100 without and with anticosmic shielding, respectively, when compared with a surface laboratory without anticosmic shielding. PMID:19944615

Breier, R; Povinec, P P

2010-01-01

380

Multiparticle azimuthal correlations in p -Pb and Pb-Pb collisions at the CERN Large Hadron Collider  

NASA Astrophysics Data System (ADS)

Measurements of multiparticle azimuthal correlations (cumulants) for charged particles in p -Pb at ?{sNN}=5.02 TeV and Pb-Pb at ?{sNN}=2.76 TeV collisions are presented. They help address the question of whether there is evidence for global, flowlike, azimuthal correlations in the p -Pb system. Comparisons are made to measurements from the larger Pb-Pb system, where such evidence is established. In particular, the second harmonic two-particle cumulants are found to decrease with multiplicity, characteristic of a dominance of few-particle correlations in p -Pb collisions. However, when a |? ? | gap is placed to suppress such correlations, the two-particle cumulants begin to rise at high multiplicity, indicating the presence of global azimuthal correlations. The Pb-Pb values are higher than the p -Pb values at similar multiplicities. In both systems, the second harmonic four-particle cumulants exhibit a transition from positive to negative values when the multiplicity increases. The negative values allow for a measurement of v2{4 } to be made, which is found to be higher in Pb-Pb collisions at similar multiplicities. The second harmonic six-particle cumulants are also found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find v2{4 } ?v2{6 } ?0 which is indicative of a Bessel-Gaussian function for the v2 distribution. For very high-multiplicity Pb-Pb collisions, we observe that the four- and six-particle cumulants become consistent with 0. Finally, third harmonic two-particle cumulants in p -Pb and Pb-Pb are measured. These are found to be similar for overlapping multiplicities, when a |? ? |>1.4 gap is placed.

Abelev, B.; Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agostinelli, A.; Agrawal, N.; Ahammed, Z.; Ahmad, N.; Ahmed, I.; Ahn, S. U.; Ahn, S. A.; Aimo, I.; Aiola, S.; Ajaz, M.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alici, A.; Alkin, A.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Anti?i?, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Armesto, N.; Arnaldi, R.; Aronsson, T.; Arsene, I. C.; Arslandok, M.; Augustinus, A.; Averbeck, R.; Awes, T. C.; Azmi, M. D.; Bach, M.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Baltasar Dos Santos Pedrosa, F.; Baral, R. C.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartke, J.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Baumann, C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bellwied, R.; Belmont-Moreno, E.; Belmont, R.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Berger, M. E.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Biel?ík, J.; Biel?íková, J.; Bilandzic, A.; Bjelogrlic, S.; Blanco, F.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Bogolyubsky, M.; Böhmer, F. V.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Bossú, F.; Botje, M.; Botta, E.; Böttger, S.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Castillo Castellanos, J.; Casula, E. A. R.; Catanescu, V.; Cavicchioli, C.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Chang, B.; Chapeland, S.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Chochula, P.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa Del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortese, P.; Cortés Maldonado, I.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dainese, A.; Dang, R.; Danu, A.; Das, D.; Das, I.; Das, K.; Das, S.; Dash, A.; Dash, S.; de, S.; Delagrange, H.; Deloff, A.; Dénes, E.; D'Erasmo, G.; de Caro, A.; de Cataldo, G.; de Cuveland, J.; de Falco, A.; de Gruttola, D.; De Marco, N.; de Pasquale, S.; de Rooij, R.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; di Bari, D.; di Liberto, S.; di Mauro, A.; di Nezza, P.; Djuvsland, Ø.; Dobrin, A.; Dobrowolski, T.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Dørheim, S.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Dutta Majumdar, A. K.; Hilden, T. E.; Ehlers, R. J.; Elia, D.; Engel, H.; Erazmus, B.; Erdal, H. A.; Eschweiler, D.; Espagnon, B.; Esposito, M.; Estienne, M.; Esumi, S.; Evans, D.; Evdokimov, S.; Fabris, D.; Faivre, J.; Falchieri, D.; Fantoni, A.; Fasel, M.; Fehlker, D.; Feldkamp, L.; Felea, D.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Floratos, E.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Garishvili, I.; Gerhard, J.; Germain, M.; Gheata, A.; Gheata, M.; Ghidini, B.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Gladysz-Dziadus, E.; Glässel, P.; Gomez Ramirez, A.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Graczykowski, L. K.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Guilbaud, M.; Gulbrandsen, K.; Gulkanyan, H.; Gumbo, M.; Gunji, T.; Gupta, A.; Gupta, R.; Khan, K. H.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.

2014-11-01

381

PPPL3278, Preprint: January 1998, UC426 The TFTR E||B Spectrometer for Mass and Energy Resolved  

E-print Network

, a novel charge exchange spectrometer using a dee­ shaped region of parallel electric and magnetic fields Multi­Ion Charge Exchange Diagnostics S.S. Medley and A.L. Roquemore Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543 USA Abstract The Charge Exchange Neutral Analyzer diagnostic

382

PPPL-3278, Preprint: January 1998, UC-426 The TFTR E||B Spectrometer for Mass and Energy Resolved  

E-print Network

, a novel charge exchange spectrometer using a dee- shaped region of parallel electric and magnetic fields Multi-Ion Charge Exchange Diagnostics S.S. Medley and A.L. Roquemore Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543 USA Abstract The Charge Exchange Neutral Analyzer diagnostic

383

Study of multiparticle jet production using calorimeters, high energy channeling, and other high energy physics research  

SciTech Connect

During this period, work was started on the construction of the backward gamma chambers to be used in experiment E683 at Fermilab. Work also is proceeding on various auxiliary experiments that can be performed with the experimental set-up. Work on the SSC accelerator and experiments began in 1984 with the participation of the principal investigator in the Snomass summer studies and continues with the funding of the accelerator and the location of its site in Texas. We are working with the large EMPACT/TEXAS collaboration on a large detector that the group has proposed. As well, the principal investigator is working on smaller experiments that can be executed at the SSC with less resources. Also, we are working on detector development and radiation tolerance of detectors such as scintillating fibers and data acquisition electronics. Experiments continue at Lehigh on growing whiskers'' in wire chambers. These whiskers affect the performance of wire chambers by providing corona discharge points within the chambers. We are able to study the growth of the whiskers in the laboratory and measure the whisker composition using Auger and ESCA spectroscopy and the scanning electron microscope. We are further developing results that were obtained earlier from various Monte-Carlo programs, including the effects of various momentum energy conservation methods on results, extrapolations to higher transverse momentum, granularity of detectors, and resolution of previous discrepancies. Results of radiation effects on various electronic devices were obtained. Work continued on new accelerator devices and concepts.

Kanofsky, A.S.

1990-10-01

384

Sequential indicator conditional simulation and indicator kriging applied to discrimination of dolomitization in GER 63-channel imaging spectrometer data  

Microsoft Academic Search

Laboratory reflectance spectra of synthetic mixtures of the carbonate minerals calcite and dolomite were measured in the visible and near-infrared wavelength region (0.4–2.5 m) using a high-spectral resolution laboratory spectrometer. The instrument measured reflectivity with an accuracy of 0.001 m, allowing detailed resolution of the carbonate spectrum. The spectra of calcite and dolomite could be characterized by the presence of

Freek van der Meer

1994-01-01

385

Opportunities in Inelastic Neutron Scattering at Oak Ridge National Laboratory  

NASA Astrophysics Data System (ADS)

The Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) are the two world class neutron scattering user facilities located at Oak Ridge National Laboratory. Inelastic scattering instruments designed to optimally utilize their source are either in, or will soon enter, the user program. The HFIR has three thermal and plans for two cold, neutron triple axis spectrometers in the user program. These instruments examine localized regions of Q and ? space with tunable resolution. The spectrometers at the SNS cover broad ranges of Q and ? space. The BASIS instrument, in the user program, uses near backscattering analyzer crystals to provide 3?eV ? resolution. The ARCS thermal to epithermal neutron spectrometer is in commissioning and the Cold Neutron Chopper Spectrometer will enter commissioning soon. These instruments provide moderate, tunable resolution, and detector coverage out to 140^o. The SEQUOIA spectrometer, complete in 2008, is the fine resolution complement of ARCS. The finest resolution is provided by the Spin-Echo spectrometer; complete in 2009. The HYSPEC spectrometer, available in 2011, will provide polarized capabilities and optimized flux for neutrons of thermal energies. Finally, the Vision chemical spectrometer will use crystal analyzers to access ? in the epithermal range. These instruments, along with representative science to be performed on each, will be presented.

Granroth, Garrett E.

2007-11-01

386

Lens system for a photo ion spectrometer  

DOEpatents

A lens system in a photo ion spectrometer for manipulating a primary ion beam and ionized atomic component is disclosed. The atomic components are removed from a sample by a primary ion beam using the lens system, and the ions are extracted for analysis. The lens system further includes ionization resistant coatings for protecting the lens system. 8 figs.

Gruen, D.M.; Young, C.E.; Pellin, M.J.

1990-11-27

387

The Orbitrap: a new mass spectrometer  

Microsoft Academic Search

Research areas such as proteomics and metabolomics are driving the demand for mass spectrometers that have high performance but modest power requirements, size, and cost. This paper describes such an instrument, the Orbitrap, based on a new type of mass analyzer invented by Makarov. The Orbitrap operates by radially trapping ions about a central spindle electrode. An outer barrel-like electrode

Qizhi Hu; Robert J. Noll; Hongyan Li; Alexander Makarov; Mark Hardman; R. Graham Cooks

2005-01-01

388

Research highlights with the spin spectrometer  

Microsoft Academic Search

The excitation energy and angular momentum dependence of the entry states in fusion reactions measured with the spin spectrometer is discussed. A new decay mode involving the onset of localized stretched dipole radiation at half the accompanying stretched E2 collective radiation is found in 157-161Yb. The appearance of this mode correlates smoothly with neutron number and spin. Possible interpretations are

D. G. Sarantites; M. Jääskeläinen; F. A. Dilmanian; H. Puchta; R. Woodward; J. R. Beene; B. C. Hensley; M. L. Halbert; J. Hattula; J. H. Barker; R. Novotny; L. Adler; R. K. Choudhury; M. N. Namboodiri; R. P. Schmitt; J. B. Natowitz

1983-01-01

389

Research highlights with the spin spectrometer  

Microsoft Academic Search

The excitation energy and angular momentum dependence of the entry states in fusion reactions measured with the spin spectrometer is discussed. A new decay mode involving the onset of localized stretched dipole radiation at half the accompanying stretched E2 collective radiation is found in \\/sup 157 -161\\/Yb. The appearance of this mode correlates smoothly with neutron number and spin. Possible

D. G. Sarantites; M. Jaeaeskelaeinen; F. A. Dilmanian; H. Puchta; R. Woodward; J. R. Beene; D. C. Hensley; M. L. Halbert; J. Hattula; J. H. Barker

1982-01-01

390

Compact imaging spectrometer utilizing immersed gratings  

DOEpatents

A compact imaging spectrometer comprising an entrance slit for directing light, lens means for receiving the light, refracting the light, and focusing the light; an immersed diffraction grating that receives the light from the lens means and defracts the light, the immersed diffraction grating directing the detracted light back to the lens means; and a detector that receives the light from the lens means.

Lerner, Scott A.

2005-12-20

391

A transmission grating spectrometer for plasma diagnostics  

SciTech Connect

Radiation temperature is an important parameter in characterizing the properties of hot plasmas. In most cases this temperature is time varying caused by the short lived and/or time dependent nature of the plasma. Thus, a measurement of the radiation flux as a function of time is quite valuable. To this end the authors have developed a spectrometer that can acquire spectra with a time resolution of less than 1 ns and covers the spectral energy range from {approximately} 60 to 1,000 eV. The spectrometer consists of an entrance slit placed relatively near the plasma, a thin gold film transmission grating with aperture, a micro channel plate (MCP) detector with a gold cathode placed at the dispersion plane and an electron lens to focus the electrons from the MCP onto a phosphor coated fiber optic plug. The phosphor (In:CdS) has a response time of {approximately} 500 ps. This detector system, including the fast phosphor is similar to one that has been previously described. The spectrometer is in a vacuum chamber that is turbo pumped to a base pressure of {approximately} 5 x 10{sup 7} torr. The light from the phosphor is coupled to two streak cameras through 100 m long fiber optic cables. The streak cameras with their CCD readouts provide the time resolution of the spectrum. The spectrometer has a built in alignment system that uses an alignment telescope and retractable prism.

Bartlett, R.J.; Hockaday, R.G. [Los Alamos National Lab., NM (United States); Gallegos, C.H.; Gonzales, J.M.; Mitton, V. [EG and G Energy Measurements, Los Alamos, NM (United States)

1995-09-01

392

A transmission grating spectrometer for plasma diagnostics  

Microsoft Academic Search

Radiation temperature is an important parameter in characterizing the properties of hot plasmas. In most cases this temperature is time varying caused by the short lived and\\/or time dependent nature of the plasma. Thus, a measurement of the radiation flux as a function of time is quite valuable. To this end we have developed a spectrometer that can acquire spectra

R. J. Bartlett; R. G. Hockaday; C. H. Gallegos; J. M. Gonzales; V. Mitton

1995-01-01

393

A transmission grating spectrometer for plasma diagnostics  

Microsoft Academic Search

Radiation temperature is an important parameter in characterizing the properties of hot plasmas. In most cases this temperature is time varying caused by the short lived and\\/or time dependent nature of the plasma. Thus, a measurement of the radiation flux as a function of time is quite valuable. To this end the authors have developed a spectrometer that can acquire

Roger J. Bartlett; Robert G. Hockaday; Cenobio H. Gallegos; Joseph M. Gonzales; Vance Mitton

1995-01-01

394

Micro IR Spectrometer Based on Blaze Grating  

Microsoft Academic Search

An infrared spectrometer which employs a blaze grating as well as an 8-element thermopile array is designed, fabricated and tested in this paper. The grating which has 80 grooves of 19.2deg blazing angle and 5 mum grating constant is precisely defined by an anisotropic etching in KOH solution from a carefully cut silicon wafer. After bonded to wafers consisting of

Hong Zhou; Tie Li; Yi Wang; Xinxin Li; Yuelin Wang

2007-01-01

395

Dyson spectrometers for infrared earth remote sensing  

Microsoft Academic Search

The Dyson spectrometer form is capable of providing high throughput, excellent image quality, low spatial and spectral distortions, and high tolerance to fabrication and alignment errors in a compact format with modest demands for weight, volume, and cooling resources. These characteristics make it attractive for hyperspectral imaging from a space-based platform. After a brief discussion of history and basic principles,

David W. Warren; David J. Gutierrez; Jeffrey L. Hall; Eric R. Keim

2008-01-01

396

Tropospheric Emission Spectrometer Product File Readers  

NASA Technical Reports Server (NTRS)

TES Product File Reader software extracts data from publicly available Tropospheric Emission Spectrometer (TES) HDF (Hierarchical Data Format) product data files using publicly available format specifications for scientific analysis in IDL (interactive data language). In this innovation, the software returns data fields as simple arrays for a given file. A file name is provided, and the contents are returned as simple IDL variables.

Fisher, Brendan M.

2010-01-01

397

Lens system for a photo ion spectrometer  

DOEpatents

A lens system in a photo ion spectrometer for manipulating a primary ion beam and ionized atomic component. The atomic components are removed from a sample by a primary ion beam using the lens system, and the ions are extracted for analysis. The lens system further includes ionization resistant coatings for protecting the lens system.

Gruen, Dieter M. (Downers Grove, IL); Young, Charles E. (Westmont, IL); Pellin, Michael J. (Napersville, IL)

1990-01-01

398

The CONTOUR remote imager and spectrometer (CRISP)  

Microsoft Academic Search

The CONTOUR Remote Imager and Spectrometer (CRISP) was a multi-function optical instrument developed for the Comet Nucleus Tour Spacecraft (CONTOUR). CONTOUR was a NASA Discovery class mission launched on July 3, 2002. This paper describes the design, fabrication, and testing of CRISP. Unfortunately, the CONTOUR spacecraft was destroyed on August 15, 2002 during the firing of the solid rocket motor

Jeffery W. Warren; Kevin J. Heffernan; Steven J. Conard; James F. Bell III; Anita L. Cochran; John D. Boldt; Alice F. Bowman; E. H. Darlington; Anthony Deluzio; Daniel Fiore; Dennis E. Fort; David Garcia; Matthew P. Grey; Bruce L. Gotwols; Ann P. Harch; John R. Hayes; Gene A. Heyler; Linda M. Howser; David C. Humm; Noam R. Izenberg; Kris E. Kosakowski; W. J. Lees; D. A. Lohr; Holger M. Luther; Douglas S. Mehoke; Scott L. Murchie; R. Alan Reiter; Brian Rider; G. D. Rogers; Deepak Sampath; Edward D. Schaefer; Thomas S. Spisz; Kim Strohbehn; Scott Svenson; Howard W. Taylor; Patrick L. Thompson; Joseph Veverka; Robert L. Williams; Paul Wilson

2004-01-01

399

Thermal emission spectrometer experiment - Mars Observer mission  

Microsoft Academic Search

The paper describes the thermal emission spectrometer (TES) designed for the Mars Observer mission. The TES measurements of the surface and the atmosphere of Mars will be used to determine and map the composition of the surface rocks, minerals, and the condensates. Examples of information that will be obtained from TES data include mineral abundance maps, condensate properties and their

Philip R. Christensen; Donald L. Anderson; Stillman C. Chase; Roger N. Clark; Hugh H. Kieffer; Michael C. Malin; John C. Pearl; James Carpenter; Nuno Bandiera; F. G. Brown; Steven Silverman

1992-01-01

400

Broadband Infrared Heterodyne Spectrometer: Final Report  

SciTech Connect

This report summarizes the most important results of our effort to develop a new class of infrared spectrometers based on a novel broadband heterodyne design. Our results indicate that this approach could lead to a near-room temperature operation with performance limited only by quantum noise carried by the incoming signal. Using a model quantum-well infrared photodetector (QWIP), we demonstrated key performance features of our approach. For example, we directly measured the beat frequency signal generated by superimposing local oscillator (LO) light of one frequency and signal light of another through a spectrograph, by injecting the LO light at a laterally displaced input location. In parallel with the development of this novel spectrometer, we modeled a new approach to reducing detector volume though plasmonic resonance effects. Since dark current scales directly with detector volume, this ''photon compression'' can directly lead to lower currents. Our calculations indicate that dark current can be reduced by up to two orders of magnitude in an optimized ''superlens'' structure. Taken together, our spectrometer and dark current reduction strategies provide a promising path toward room temperature operation of a mid-wave and possibly long-wave infrared spectrometer.

Stevens, C G; Cunningham, C T; Tringe, J W

2010-12-16

401

A portable surface-enhanced Raman spectrometer  

SciTech Connect

We describe the development of a simple and compact spectrometer for use in Raman and Surface-enhanced Raman Scattering (SERS) analysis. The instrument using an avalanche photodiode is designed to use under field conditions with simple optical samples. Examples of measurement of a variety of chemicals are used to illustrate the performance of the instrument. 26 refs., 4 figs.

Sutherland, W.S.; Alarie, J.P.; Stokes, D.L.; Vo-Dinh, T. [Oak Ridge National Lab., TN (United States)

1994-12-31

402

Imaging mass spectrometer with mass tags  

DOEpatents

A method of analyzing biological material by exposing the biological material to a recognition element, that is coupled to a mass tag element, directing an ion beam of a mass spectrometer to the biological material, interrogating at least one region of interest area from the biological material and producing data, and distributing the data in plots.

Felton, James S.; Wu, Kuang Jen J.; Knize, Mark G.; Kulp, Kristen S.; Gray, Joe W.

2013-01-29

403

Imaging mass spectrometer with mass tags  

DOEpatents

A method of analyzing biological material by exposing the biological material to a recognition element, that is coupled to a mass tag element, directing an ion beam of a mass spectrometer to the biological material, interrogating at least one region of interest area from the biological material and producing data, and distributing the data in plots.

Felton, James S.; Wu, Kuang Jen; Knize, Mark G.; Kulp, Kristen S.; Gray, Joe W.

2010-06-01

404

Reflecting Schmidt/Littrow Prism Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

High resolution achieved with wide field of view. Imaging Spectrometer features off-axis reflecting optics, including reflecting "slit" that also serves as field flattener. Only refracting element is prism. By scanning slit across object or scene and timing out signal, both spectral and spatial information in scene are obtained.

Breckinridge, J. B.; Page, N. A.; Shack, R. V.; Shannon, R. R.

1985-01-01

405

Apollo 17 ultraviolet spectrometer experiment (S-169)  

NASA Technical Reports Server (NTRS)

The scientific objectives of the ultraviolet spectrometer experiment are discussed, along with design and operational details, instrument preparation and performance, and scientific results. Information gained from the experiment is given concerning the lunar atmosphere and albedo, zodiacal light, astronomical observations, spacecraft environment, and the distribution of atomic hydrogen in the solar system and in the earth's atmosphere.

Fastie, W. G.

1974-01-01

406

Gamma Ray Burst All-Sky Spectrometer  

Microsoft Academic Search

The Gamma Ray Burst All-Sky Spectrometer Experiment (GASE) is designed to detect radio emission from gamma ray bursts (GRB's). Radio emission from GRB's could help us better understand the plasma physics of the blast and might also help us measure dark energy. GASE uses short-baseline interferometry with eight dipole antennas located at the MIT Haystack Observatory. These antennas measure the

Arielle Steger

2011-01-01

407

LUVIMS lunar UV and IR mapping spectrometer  

NASA Astrophysics Data System (ADS)

A new imaging spectrometer particularly designed for the lunar mission MORO (Moon ORbiting Observatory) is presented. This spectrometer, named LUVIMS (Lunar UV and Infrared Mapping Spectrometer), is characterized by high performances - high spectral, high spatial resolution - being at the same time small, light weight and has a low power consumption. An imaging spectrometer, operating in the visible an infrared, is able to provide information about lunar mineralogical composition. By means of LUVIMS it will be possible to identify most of the mineralogical species and to relate their distribution with the surface morphology LUVIMS scientific objectives concerned the geochemical characterization of the Moon's surface in terms of global mapping, identification of different material and their distribution, mineralogical analysis of different terrain observations with high spatial resolution added to high spectral resolution can be the most powerful technique to have information on the lunar material origin and evolution. The spectrometer has been designed in order to work properly on either a tri-axis stabilized or a spinning spacecraft. In fact MORO has being studied as a candidate mission for the third cycle of Medium size missions, M3, in the framework of ESA's Horizon 2000 scientific programme. During the assessment phase, parametric solutions have been evaluated, but it has been shown that LUVIMS can fulfil the scientific requirements in any of the proposed spacecraft configurations. During phase A of the MORO mission the three-axis stabilized option has been selected, however it is thought that the evaluation of the performance of LUVIMS for a spinning spacecraft can be relevant also for other small spinning satellites.

Coradini, A.; De Sanctis, M. C.; Reininger, F.; Bonsignori, R.; Racca, G.; Chicarro, A.

1996-10-01

408

OZSPEC-2: An improved broadband high-resolution elliptical crystal x-ray spectrometer for high-energy density physics experiments (invited)  

Microsoft Academic Search

A novel time, space, and energy-resolved x-ray spectrometer has been developed which produces, in a single snapshot, a broadband and relatively calibrated spectrum of the x-ray emission from a high-energy density laboratory plasma. The opacity zipper spectrometer (OZSPEC-1) records a nearly continuous spectrum for x-ray energies from 240 to 5800 eV in a single shot. The second-generation OZSPEC-2, detailed in

R. F. Heeter; S. G. Anderson; R. Booth; G. V. Brown; J. Emig; S. Fulkerson; T. McCarville; D. Norman; M. B. Schneider; B. K. F. Young

2008-01-01

409

Development and performance of a miniature, low cost mass spectrometer  

E-print Network

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)

2011-01-01

410

Laboratory Tests  

MedlinePLUS

... factors can affect test results, including: sex age race medical history general health specific foods drugs you are taking how closely your follow preparatory instructions variations in laboratory ...

411

Measurement of flow harmonics with multi-particle cumulants in Pb+Pb collisions at TeV with the ATLAS detector  

NASA Astrophysics Data System (ADS)

ATLAS measurements of the azimuthal anisotropy in lead-lead collisions at TeV are shown using a dataset of approximately 7 b collected at the LHC in 2010. The measurements are performed for charged particles with transverse momenta GeV and in the pseudorapidity range . The anisotropy is characterized by the Fourier coefficients, , of the charged-particle azimuthal angle distribution for -4. The Fourier coefficients are evaluated using multi-particle cumulants calculated with the generating function method. Results on the transverse momentum, pseudorapidity and centrality dependence of the coefficients are presented. The elliptic flow, , is obtained from the two-, four-, six- and eight-particle cumulants while higher-order coefficients, and , are determined with two- and four-particle cumulants. Flow harmonics measured with four-particle cumulants are significantly reduced compared to the measurement involving two-particle cumulants. A comparison to measurements obtained using different analysis methods and previously reported by the LHC experiments is also shown. Results of measurements of flow fluctuations evaluated with multi-particle cumulants are shown as a function of transverse momentum and the collision centrality. Models of the initial spatial geometry and its fluctuations fail to describe the flow fluctuations measurements.

Aad, G.; Abbott, B.; Abdallah, J.; Abdel Khalek, S.; Abdinov, O.; Aben, R.; Abi, B.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B. S.; Adamczyk, L.; Adams, D. L.; Adelman, J.; Adomeit, S.; Adye, T.; Agatonovic-Jovin, T.; Aguilar-Saavedra, J. A.; Agustoni, M.; Ahlen, S. P.; Ahmadov, F.; Aielli, G.; Akerstedt, H.; Åkesson, T. P. A.; Akimoto, G.; Akimov, A. V.; Alberghi, G. L.; Albert, J.; Albrand, S.; Alconada Verzini, M. J.; Aleksa, M.; Aleksandrov, I. N.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Alimonti, G.; Alio, L.; Alison, J.; Allbrooke, B. M. M.; Allison, L. J.; Allport, P. P.; Almond, J.; Aloisio, A.; Alonso, A.; Alonso, F.; Alpigiani, C.; Altheimer, A.; Alvarez Gonzalez, B.; Alviggi, M. G.; Amako, K.; Amaral Coutinho, Y.; Amelung, C.; Amidei, D.; Amor Dos Santos, S. P.; Amorim, A.; Amoroso, S.; Amram, N.; Amundsen, G.; Anastopoulos, C.; Ancu, L. S.; Andari, N.; Andeen, T.; Anders, C. F.; Anders, G.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Anduaga, X. S.; Angelidakis, S.; Angelozzi, I.; Anger, P.; Angerami, A.; Anghinolfi, F.; Anisenkov, A. V.; Anjos, N.; Annovi, A.; Antonaki, A.; Antonelli, M.; Antonov, A.; Antos, J.; Anulli, F.; Aoki, M.; Aperio Bella, L.; Apolle, R.; Arabidze, G.; Aracena, I.; Arai, Y.; Araque, J. P.; Arce, A. T. H.; Arguin, J.-F.; Argyropoulos, S.; Arik, M.; Armbruster, A. J.; Arnaez, O.; Arnal, V.; Arnold, H.; Arratia, M.; Arslan, O.; Artamonov, A.; Artoni, G.; Asai, S.; Asbah, N.; Ashkenazi, A.; Åsman, B.; Asquith, L.; Assamagan, K.; Astalos, R.; Atkinson, M.; Atlay, N. B.; Auerbach, B.; Augsten, K.; Aurousseau, M.; Avolio, G.; Azuelos, G.; Azuma, Y.; Baak, M. A.; Baas, A. E.; Bacci, C.; Bachacou, H.; Bachas, K.; Backes, M.; Backhaus, M.; Backus Mayes, J.; Badescu, E.; Bagiacchi, P.; Bagnaia, P.; Bai, Y.; Bain, T.; Baines, J. T.; Baker, O. K.; Balek, P.; Balli, F.; Banas, E.; Banerjee, Sw.; Bannoura, A. A. E.; Bansal, V.; Bansil, H. S.; Barak, L.; Baranov, S. P.; Barberio, E. L.; Barberis, D.; Barbero, M.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnett, B. M.; Barnett, R. M.; Barnovska, Z.; Baroncelli, A.; Barone, G.; Barr, A. J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Bartoldus, R.; Barton, A. E.; Bartos, P.; Bartsch, V.; Bassalat, A.; Basye, A.; Bates, R. L.; Batley, J. R.; Battaglia, M.; Battistin, M.; Bauer, F.; Bawa, H. S.; Beattie, M. D.; Beau, T.; Beauchemin, P. H.; Beccherle, R.; Bechtle, P.; Beck, H. P.; Becker, K.; Becker, S.; Beckingham, M.; Becot, C.; Beddall, A. J.; Beddall, A.; Bedikian, S.; Bednyakov, V. A.; Bee, C. P.; Beemster, L. J.; Beermann, T. A.; Begel, M.; Behr, K.; Belanger-Champagne, C.; Bell, P. J.; Bell, W. H.; Bella, G.; Bellagamba, L.; Bellerive, A.; Bellomo, M.; Belotskiy, K.; Beltramello, O.; Benary, O.; Benchekroun, D.; Bendtz, K.; Benekos, N.; Benhammou, Y.; Benhar Noccioli, E.; Benitez Garcia, J. A.; Benjamin, D. P.; Bensinger, J. R.; Benslama, K.; Bentvelsen, S.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Berghaus, F.; Beringer, J.; Bernard, C.; Bernat, P.; Bernius, C.; Bernlochner, F. U.; Berry, T.; Berta, P.; Bertella, C.; Bertoli, G.; Bertolucci, F.; Bertsche, C.; Bertsche, D.; Besana, M. I.; Besjes, G. J.; Bessidskaia, O.; Bessner, M.; Besson, N.; Betancourt, C.; Bethke, S.; Bhimji, W.; Bianchi, R. M.; Bianchini, L.; Bianco, M.; Biebel, O.; Bieniek, S. P.; Bierwagen, K.; Biesiada, J.; Biglietti, M.; Bilbao De Mendizabal, J.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Black, C. W.; Black, J. E.; Black, K. M.; Blackburn, D.; Blair, R. E.; Blanchard, J.-B.; Blazek, T.; Bloch, I.; Blocker, C.; Blum, W.; Blumenschein, U.; Bobbink, G. J.; Bobrovnikov, V. S.; Bocchetta, S. S.; Bocci, A.; Bock, C.; Boddy, C. R.; Boehler, M.; Boek, T. T.; Bogaerts, J. A.; Bogdanchikov, A. G.; Bogouch, A.; Bohm, C.; Bohm, J.; Boisvert, V.; Bold, T.; Boldea, V.; Boldyrev, A. S.; Bomben, M.; Bona, M.; Boonekamp, M.; Borisov, A.; Borissov, G.; Borri, M.; Borroni, S.; Bortfeldt, J.; Bortolotto, V.; Bos, K.; Boscherini, D.; Bosman, M.; Boterenbrood, H.; Boudreau, J.; Bouffard, J.; Bouhova-Thacker, E. V.; Boumediene, D.; Bourdarios, C.; Bousson, N.; Boutouil, S.; Boveia, A.; Boyd, J.; Boyko, I. R.; Bracinik, J.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J. E.; Braun, H. M.; Brazzale, S. F.; Brelier, B.; Brendlinger, K.; Brennan, A. J.; Brenner, R.; Bressler, S.; Bristow, K.; Bristow, T. M.; Britton, D.; Brochu, F. M.; Brock, I.; Brock, R.; Bromberg, C.; Bronner, J.; Brooijmans, G.; Brooks, T.; Brooks, W. K.; Brosamer, J.; Brost, E.; Brown, J.; Bruckman de Renstrom, P. A.; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Bryngemark, L.; Buanes, T.; Buat, Q.; Bucci, F.

2014-11-01

412

Measured properties of an out-of-plane spectrometer  

Microsoft Academic Search

We report the results of measurements of the properties of a prototype out-of-plane magnetic spectrometer (OOPS). This spectrometer is one of four identical modules which, together with a support structure, comprise the OOPS cluster. The performance of the spectrometer was found to closely match its design characteristics.

J. B. Mandeville; L. S. Cardman; S. M. Dolfini; W. Kim; R. M. Laszewski; C. N. Papanicolas; S. E. Williamson; R. Alarcon; J. Görgen; D. Martinez; K. Dow; M. M. Farkhondeh; D. Tieger; J. Zumbro; M. Epstein; D. Margaziotis; A. Bernstein; W. Bertozzi; V. Bhushan; S. Gilad; M. Holtrop; D. Jordan; T. McIlvain; L. Weinstein; R. Beck; W. Boeglin; E. A. J. M. Offermann

1994-01-01

413

Investigation and Progress of MicroSpectrometer's Light Splitting System  

Microsoft Academic Search

It becomes possible to micro spectrometers with the development of micromachining techniques such as MEMS (micro electro mechanical systems). According to different dispersive elements used by micro spectrometers, the paper mainly illuminates the principle and fabrication technology of typical micro spectrometers whose dispersive elements adopt silicon micro grating, filter and Febry-Perot resonant cavity. The paper briefly summarizes the advantages, disadvantages

Wang Yongqing; Li Chunli; Sun Rongxia; Wang Haizhou

2007-01-01

414

Fabrication of a bolometric infrared micro-spectrometer  

Microsoft Academic Search

The bolometric infrared spectrometer instantaneously detects the incoming IR spectra by detecting the decrease or increase of bolometer resistance due to its temperature change caused by the incident infrared light. In this paper, the design and fabrication methods of bolometric IR spectrometer are presented. The IR spectrometer reported in this paper consists of a bolometric IR detector array made of

Jae Chang Yang; Ju Chan Choi; Ho Jung; Seong Ho Kong

2007-01-01

415

A personal digital assistant-based portable radiation spectrometer  

Microsoft Academic Search

A nuclear spectrometer based on a personal digital assistant (PDA) has been designed, built and tested. This portable radiation spectrometer, PDA SPECTROMETER, can be used for data acquisition and spectrum analysis in a field that requiring output of radiation dose rate and count rate as well as nuclide identification. A Complex Programmable Logic Design (CPLD) circuit block is built for

P. C. Huang; H. P. Chou; K. B. Chen

2007-01-01

416

The Constellation-X reflection grating spectrometer Jean Cottama  

E-print Network

The Constellation-X reflection grating spectrometer Jean Cottama , Webster Cashb , Kathryn A University, SLAC, Menlo Park, CA USA 94025 ABSTRACT The Constellation-X Reflection Grating Spectrometer (RGS. Keywords: X-ray, spectrometer, grating, CCD, Constellation-X 1. INTRODUCTION Constellation-X1 is one

417

IR spectrometers for Venus and Mars measurements  

NASA Astrophysics Data System (ADS)

The SOIR spectrometer [1] is an infra-red spectrometer that has performed over 500 solar occultation measurements of the Venus atmosphere, profiling major and minor constituents and studying aerosol absorption, temperature and pressure effects. NOMAD is a 3-channel spectrometer for Mars occultation, limb and nadir measurements. 2 channels are infra-red, the other UV-visible. We will present the technology that enables SOIR and NOMAD to get to parts per billion mixing ratio sensitivities for trace atmospheric components and highlight the improvements made to the SOIR design to enable nadir viewing with NOMAD. Key components include the Acousto-Optical Tunable Filter with radio frequency driver that allows these spectrometers to select the wavelength domain under observation with no need for mechanical moving parts. It also allows background measurements because it is opaque when no RF is applied. The grating with 4 grooves/mm is a very hard to manufacture optical component, and suppliers were very difficult to find. The detector-cooler combination (working at 90K) is from Sofradir/Ricor and the model on board Venus Express is still working after 6 years in space (more on/off cycles that ON hour lifetime problem). The detector MCT mix is slightly altered for nadir observation, in order to reduce thermal background noise and the nadir channel spectrometer is cooled down to 173K by a large V-groove radiator. All the optical components have been enlarged to maximise signal throughput and the slit (that determines spatial and spectral resolution) has also been increased. The spacecraft attitude control system switches from yaw steering for nadir to inertial pointing for solar occultations. 1. Nevejans, D., E. Neefs, E. Van Ransbeeck, S. Berkenbosch, R. Clairquin, L. De Vos, W. Moelans, S. Glorieux, A. Baeke, O. Korablev, I. Vinogradov, Y. Kalinnikov, B. Bach, J.P. Dubois, and E. Villard, Compact high-resolution space-borne echelle grating spectrometer with AOTF based on order sorting for the infrared domain from 2.2 to 4.3 micrometer. Applied Optics, 45(21), 5191-5206 (2006)

Drummond, Rachel; Neefs, Eddy; Vandaele, Ann C.

2012-07-01

418

Broadband Single-Shot Electron Spectrometer for GeV-Class Laser Plasma Based Accelerators  

SciTech Connect

Laser-plasma-based accelerators can provide electrons over a broad energy range and/or with large momentum spread. The electron beam energy distribution can be controlled via accurate control of laser and plasma properties, and beams with energies ranging from'0.5 to 1000 MeV have been observed. Measuring these energy distributions in a single shot requires the use of a diagnostic with large momentum acceptance and, ideally, sufficient resolution to accurately measure energy spread in the case of narrow energy spread. Such a broadband single-shot electron magnetic spectrometer for GeV-class laser-plasma-based accelerators has been developed at Lawrence Berkeley National Laboratory. A detailed description of the hardware and the design concept is presented, as well as a performance evaluation of the spectrometer. The spectrometer covered electron beam energies raging from 0.01 to 1.1 GeV in a single shot, and enabled the simultaneous measurement of the laser properties at the exit of the accelerator through the use of a sufficiently large pole gap. Based on measured field maps and 3rd-order transport analysis, a few percent-level resolution and determination of the absolute energy were achieved over the entire energy range. Laser-plasma-based accelerator experiments demonstrated the capability of the spectrometer as a diagnostic and its suitability for such a broadband electron source.

Nakamura, K.; Wan, W.; Ybarrolaza, N.; Syversrud, D.; Wallig, J.; Leemans, W.P.

2008-05-01

419

Two CdZnTe Detector-Equipped Gamma-ray Spectrometers for Attribute Measurements on Irradiated Nuclear Fuel  

SciTech Connect

Some United States Department of Energy-owned spent fuel elements from foreign research reactors (FRRs) are presently being shipped from the reactor location to the US for storage at the Idaho National Engineering and Environmental Laboratory (INEEL). Two cadmium zinc telluride detector-based gamma-ray spectrometers have been developed to confirm the irradiation status of these fuels. One spectrometer is configured to operate underwater in the spent fuel pool of the shipping location, while the other is configured to interrogate elements on receipt in the dry transfer cell at the INEEL’s Interim Fuel Storage Facility (IFSF). Both units have been operationally tested at the INEEL.

Hartwell, John Kelvin; Winston, Philip Lon; Marts, Donna Jeanne; Moore-McAteer, Lisa Dawn; Taylor, Steven Cheney

2003-04-01

420

Data analysis for Skylab proton spectrometer  

NASA Technical Reports Server (NTRS)

The data from a proton spectrometer flown aboard Skylab is examined. The instrument is sensitive to protons in the energy range 18 to 400 MeV. A partial failure of the spectrometer restricted spectral analysis to two energy bands, 18 to 27 MeV and 27 to 400 MeV. The directional data showed that a Gaussian angular distribution parameter of at least 70 degrees is required for the low energy band and at least 40 degrees for the high energy band. The data, integrated over angle, indicate that the AP3 model extrapolated down to 18-27 MeV is high by factors of 2 to 5 over most of the B-L space mapped. In the 27 to 400 MeV range, the AP3 model is 20 to 100 percent low at low and high values of L, and is high at medium L values in the B-L space mapped.

Hill, C. W.

1976-01-01

421

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

2011-09-01

422

GOSPEC - The infrared spectrometer of TIRGO  

NASA Astrophysics Data System (ADS)

This paper describes the structure of the GOSPEC, a new instrument for the TIRGO observatory. It is a cryogenically cooled grating spectrometer equipped with a seven-element InSb array detector, which can be used both as a spectrometer with a resolution of 300-2600 between 1 and 5 microns and as a mapping photometer in the IR bands J-H-K-L-M. The optical system's grating is in Littrow configuration, with 300 grooves/mm and the blaze angle of 36 deg 52 min. The back of the grating is a plane mirror, so that when the grating is rotated 180 deg, the instrument works as a photometer with mapping capability in the band defined by the filters. The results of tests showed a good optical quality of the image (the image size at 80 percent of energy was about 0.04 mm) and a good mechanical stability of the optical system.

Gennari, S.

423

PAC spectrometer for condensed matter investigation  

NASA Astrophysics Data System (ADS)

A four-detector spectrometer of perturbed angular ?? correlations is developed for investigation of hyperfine interactions in condensed matter. It allows measurements with practically any type of detectors. A unique circuit design involving a specially developed Master PAC unit combined with a computer allows a substantially higher efficiency, reduced set-up time and simpler operation in comparison with traditional PAC spectrometers. A cryostat and a high-temperature oven allow measurements in the temperature range from 120 to 1300 K. An encased electromagnet makes it possible to generate a magnetic field up to 2 T on a sample. The measurement system includes a press with a specially designed high-pressure chamber allowing on-line PAC measurements in samples under pressure up to 60 GPa.

Brudanin, V. B.; Filossofov, D. V.; Kochetov, O. I.; Korolev, N. A.; Milanov, M.; Ostrovskiy, I. V.; Pavlov, V. N.; Salamatin, A. V.; Timkin, V. V.; Velichkov, A. I.; Fomicheva, L. N.; Tsvyaschenko, A. V.; Akselrod, Z. Z.

2005-08-01

424

Compact imaging spectrometer utilizing immersed gratings  

DOEpatents

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)

2007-07-03

425

Interface for liquid chromatograph-mass spectrometer  

DOEpatents

A moving belt interface for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer.

Andresen, Brian D. (Pleasanton, CA); Fought, Eric R. (Livermore, CA)

1989-01-01

426

Interface for liquid chromatograph-mass spectrometer  

DOEpatents

A moving belt interface is described for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer. 8 figs.

Andresen, B.D.; Fought, E.R.

1989-09-19

427

Dds-Based Fast Scan Spectrometer  

NASA Astrophysics Data System (ADS)

The technique of direct digital synthesis (DDS) has two important features which enable its application in microwave spectroscopy: micro-Hz tuning resolution and extremely fast frequency switching with continuous phase. We have applied a direct digital synthesizer in a PLL-spectrometer based on backward-wave oscillator (BWO). As result we have obtained an instrument that can cover a 100 GHz bandwidth in less than one hour with high spectral resolution and high precision of frequency measurement. The application of the spectrometer to sub-millimeter wave survey spectra records of several isotopic species of astrophysical molecules (methanol, formamide, methyl formate, aziridine) will be discussed. The support of Université de Lille 1 and le Programme National de Physique Chimie du Milieu Interstellaire is gratefully acknowledged.

Alekseev, E. A.; Motiyenko, R. A.; Margulès, L.

2010-06-01

428

Imaging spectrometer wide field catadioptric design  

DOEpatents

A wide field catadioptric imaging spectrometer with an immersive diffraction grating that compensates optical distortions. The catadioptric design has zero Petzval field curvature. The imaging spectrometer comprises an entrance slit for transmitting light, a system with a catadioptric lens and a dioptric lens for receiving the light and directing the light, an immersion grating, and a detector array. The entrance slit, the system for receiving the light, the immersion grating, and the detector array are positioned wherein the entrance slit transmits light to the system for receiving the light and the system for receiving the light directs the light to the immersion grating and the immersion grating receives the light and directs the light through the system for receiving the light to the detector array.

Chrisp; Michael P. (Danville, CA)

2008-08-19

429

Cryogenic system for a superconducting spectrometer  

SciTech Connect

The Heavy Ion Spectrometer System (HISS) relies upon superconducting coils of cryostable, pool boiling design to provide a maximum particle bending field of 3 tesla. This paper describes the cryogenic facility including helium refrigeration, gas management, liquid nitrogen system, and the overall control strategy. The system normally operates with a 4 K heat load of 150 watts; the LN/sub 2/ circuits absorb an additional 4000 watts. 80K intercept control is by an LSI 11 computer. Total available refrigeration at 4K is 400 watts using reciprocating expanders at the 20K and 4K level. The minicomputer has the capability of optimizing overall utility input cost by varying operating points. A hybrid of pneumatic, analog, and digital control is successful in providing full time unattended operation. The 7m diameter magnet/cryostat assembly is rotatable through 180 degrees to provide a variety of spectrometer orientations.

Porter, J.

1983-03-01

430

Forward production of. pi. ° mesons in the multiparticle reaction. pi. ⁻p. --> pi. °. pi. \\/sup +\\/. pi. ⁻. pi. ⁻p at momentum 4. 5 GeV\\/c  

Microsoft Academic Search

The mechanism of forward ..pi..°-meson production in the multiparticle ..pi..⁻p..--> pi..°..pi..\\/sup +\\/..pi..⁻..pi..⁻p reaction at momentum 4.5 GeV\\/c is discussed, and the resonance states corresponding to this final state of the reaction are compared.

Y. D. Aleshin; A. I. Vovk; A. G. Drutskoi; I. L. Kiselevich; I. A. Melnichenko; V. I. Mikhailichenko; S. Y. Nikitin; L. A. Prostova; V. I. Silaev; A. V. Shidlovskii

1987-01-01

431

Forward production of. pi. /sup 0/ mesons in the multiparticle reaction. pi. /sup -/p. --> pi. /sup 0/. pi. /sup +/. pi. /sup -/. pi. /sup -/p at momentum 4. 5 GeV/c  

SciTech Connect

The mechanism of forward ..pi../sup 0/-meson production in the multiparticle ..pi../sup -/p..--> pi../sup 0/..pi../sup +/..pi../sup -/..pi../sup -/p reaction at momentum 4.5 GeV/c is discussed, and the resonance states corresponding to this final state of the reaction are compared.

Aleshin, Y.D.; Vovk, A.I.; Drutskoi, A.G.; Kiselevich, I.L.; Mel'nichenko, I.A.; Mikhailichenko, V.I.; Nikitin, S.Y.; Prostova, L.A.; Silaev, V.I.; Shidlovskii, A.V.; and others

1987-12-01

432

Pioneer Venus large probe neutral mass spectrometer  

NASA Technical Reports Server (NTRS)

The deuterium hydrogen abundance ratio in the Venus atmosphere was measured while the inlets to the Pioneer Venus large probe mass spectrometer were coated with sulfuric acid from Venus' clouds. The ratio is (1.6 + or - 0.2) x 10 to the minus two power. It was found that the 100 fold enrichment of deuterium means that Venus outgassed at least 0.3% of a terrestrial ocean and possibly more.

Hoffman, J.

1982-01-01

433

Parallel processor for the spin spectrometer  

Microsoft Academic Search

Current maximum data rates from the Spin Spectrometer of about 5000 events\\/s (up to 1.3 MBytes\\/s) and minimum analysis requiring at least 3000 operations\\/event require a CPU cycle time near 70 ns. In order to achieve an effective cycle time of 70 ns, a parallel processing device is proposed. Up to 4 independent processors will be implemented in parallel in

D. C. Hensley

1983-01-01

434

Scanning imaging absorption spectrometer for atmospheric chartography  

NASA Technical Reports Server (NTRS)

The SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY is an instrument which measures backscattered, reflected, and transmitted light from the earth's atmosphere and surface. SCIAMACHY has eight spectral channels which observe simultaneously the spectral region between 240 and 1700 nm and selected windows between 1940 and 2400 nm. Each spectral channel contains a grating and linear diode array detector. SCIAMACHY observes the atmosphere in nadir, limb, and solar and lunar occultation viewing geometries.

Burrows, John P.; Chance, Kelly V.

1991-01-01

435

Capillary zone electrophoresis-mass spectrometer interface  

DOEpatents

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conductors is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer. 1 fig.

D`Silva, A.

1996-08-06

436

Silicon-based micro-Fourier spectrometer  

Microsoft Academic Search

A novel Fourier spectrometer based on a partly transparent thin-film detector in combination with a tunable silicon micromachined mirror was developed. The operation principle based on the detection of an intensity profile of a standing-wave by introducing a partly transparent detector in the standing-wave. Varying the position of the mirror results in a phase shift of the standing-wave and thus

Dietmar Knipp; Helmut Stiebig; Sameer R. Bhalotra; Eerke Bunte; Helen L. Kung; David A. B. Miller

2005-01-01

437

Spectrometer of high energy gamma quantums  

NASA Technical Reports Server (NTRS)

A detailed description of the apparatus GG-2M is given. The spectrometer contains a Cerenkov and scintillation (including anticoincidence) counter. The energies of the gamma quantums are measured by a shower calorimeter, in which scintillation counters are used in the capacity of detectors. Results are given for tuning the device on mu-mesons of cosmic rays. The data of physical tuning allow more reliable interpretation of the results of measurements which are received on the satellites.

Blokhintsev, I. D.; Melioranskiy, A. S.; Kalinkin, L. F.; Nagornykh, Y. I.; Pryakhin, Y. A.

1979-01-01

438

Advanced mass spectrometers for hydrogen isotope analyses  

Microsoft Academic Search

Two advanced prototype mass spectrometers for the accurate analysis of mixtures of the hydrogen isotopes were evaluated. The GAZAB is a large double-focusing instrument with a resolution of 2000 at mass 4 and an abundance sensitivity of greater than 100,000 for the HT-D2 doublet. The MAT 250 HDT is a smaller, simpler, stigmatic focusing instrument with exceptionally high ion intensities

P. Chastagner

1984-01-01

439

The Oriented Scintillation Spectrometer Experiment - Instrument description  

Microsoft Academic Search

The Oriented Scintillation Spectrometer Experiment on the Arthur Holly Compton Gamma Ray Observatory satellite uses four actively shielded NaI (Tl)-CsI(Na) phoswich detectors to provide gamma-ray line and continuum detection capability in the 0.05-10 MeV energy range. The instrument includes secondary capabilities for gamma-ray and neutron detection between 10 and 250 MeV. The detectors have 3.8 deg x 11.04 deg (FWHM)

W. N. Johnson; R. L. Kinzer; J. D. Kurfess; M. S. Strickman; W. R. Purcell; D. A. Grabelsky; M. P. Ulmer; D. A. Hillis; G. V. Jung; R. A. Cameron

1993-01-01

440

Design of a portable microfiber optic spectrometer  

NASA Astrophysics Data System (ADS)

Spectrum examination is widely used in scientific research and production. With the development of scientific research and production, the trend of spectrum examination is from indoor to outdoor in situ examination and on-line monitor. So the spectrometer is required to be more minimal. A new type of portable micro fiber spectrometer, using CCD, blaze grating, and two spherical mirror, a small dispersing system based on crossing Czerny-Turner structure, is designed based on this kind of requirement. By analyzing optical system structure, the relation among parameters of these components has been found out in order to fix basic parameters for miniaturized spectrometer; its working wavelength is 200-910nm. The entire spectrum is detected by a CCD for one time, the selection of CCD is product of Toshiba Corporation, linear charge coupled device (L.CCD) TCD1304AP, then received light signal is converted to an electrical signal. The system's hardware circuit includes CPLD, MCU, the CCD driving timing circuit, signal conditioning circuits, high-speed A/D sampling and transform timing circuit. A new kind of driving and sampling system which is high integrated for multi-channel has been designed by using CPLD (complex programmable logical device) and MCU. In this system, many function modules can be generated by logic cells inside of the CPLD chip, such as the driving pulse of CCD, the driving timing of high-speed A/D sampling converter and storage system and so on. In the end, the A/D results can be transmitted to computer by MCU for storage, processing and analysis. The CPLD is programmed in VHDL and compiled, synthesized, simulated and burned with the helping of the environment of Quartus II. The design of portable micro fiber spectrometer has the feature of wide spectrum range and high resolving power, so the system is especially suitable in the application of portable filed examination.

Tong, Jian-ping; Yang, Yang; Sui, Cheng-hua; Xu, Dang-yang; Wang, fei

2010-10-01

441

Lead Slowing Down Spectrometer Status Report  

Microsoft Academic Search

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

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

2012-01-01

442

Compact Ion Source for Mass Spectrometers  

NASA Technical Reports Server (NTRS)

Cyclotron-resonance device uses miniature components and permanent magnet for small size, low weight, and low cost. Gas molecules are ionized by electrons from hot filament. Magnetic field, acting with electrostatic drift field, causes ions to move in circles with a superimposed drift perpendicular to both fields, toward the exit. Compact source can be used for studying ion-molecule reactions by ion cyclotron-resonance methods in conventional mass spectrometer with either magnetic sector or quadrupole sector.

Anicich, V. G.; Huntress, W. T. J.

1982-01-01

443

Capillary zone electrophoresis-mass spectrometer interface  

DOEpatents

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conducts is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer.

D'Silva, Arthur (Ames, IA)

1996-08-06

444

Construction of Ibaraki prefectural neutron spectrometers  

Microsoft Academic Search

Ibaraki Prefectural Government established Science Frontier 21 Initiative (SF21) in 2001. In SF21 the active co-operations between Tsukuba, Tokai and Hitachi areas are accelerated and two Prefecture's neutron spectrometers have been constructed in order to establish the advanced industrial zone by setting the J-PARC as a key component. In addition, the industrial applications of neutron will be promoted. The objectives

Makoto Hayashi; Toru Ishigaki; Takashi Kamiyama; Ichiro Tanaka

2009-01-01

445

Synchronized high speed scanning infrared spectrometer.  

PubMed

A spectrometer which scans a wavelength band of 0.6 micro in 30 microsec and is useful from 2-6 micro is described. The instrument can be synchronized with a pulsed source with a minimum triggering delay of 15microsec. The instrument is basically an Ebert spectrometer equipped with an indium antimonide detector at the exit slit, an aluminum scanning mirror placed 5 cm before the exit slit, and a wavelength calibration signal generator. The scanning mirror, which is supported on pivots inside a helical coil, deflects the spectrum through an angle of approximately 90 degrees onto the exit slit. When a capacitor is discharged through the coil, the resulting magnetic field spins the aluminum mirror causing the spectrum to move across the exit slit. The wavelength calibration signal generator produces a series of electrical pulses as the scanning mirror turns, permitting wavelength calibration when the pulses are displayed below the spectrometer signal on a dual beam oscilloscope. Using this instrument on a shock tube, data have bee obtained on the absolute spectral radiation intensity of air, nitrogen, neon, and argon heated by reflected shocks to equilibrium temperatures in the range of 6000 degrees K to 10,000 degrees K. In this temperature region with these gases, an important source of continuum radiation is neutral Bremsstrahlung caused by the inelastic scattering of electrons from neutral atoms and molecules. By employing the scanning ir spectrometer it has been possible to separate the continuum radiation from contributions owing to lines and bands and determine the cross section for the neutral Bremsstrahlung. PMID:20057870

Camm, J C; Taylor, R L; Lynch, R

1967-05-01

446

Time Dispersive Spectrometer Using Digital Switching Means  

DOEpatents

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)

2004-09-07

447

Ten channel filter-fluorescer spectrometer  

Microsoft Academic Search

A ten channel filter-fluorescer spectrometer was designed for measuring x-ray spectra from 2 to 115 keV at the Argus and Shiva laser facilities. Previously x-ray spectra were measured with filtered detectors; however, the higher fluxes and more complicated spectra observed in recent experiments requires the greater photon energy definition of this technique. Five filter-detector channels are also incorporated in the

B. L. Pruett; K. G. Tirsell; H. N. Kornblum; S. S. Glaros; D. E. Campbell; V. W. Slivinsky

1978-01-01

448

Method of multiplexed analysis using ion mobility spectrometer  

DOEpatents

A method for analyzing analytes from a sample introduced into a Spectrometer by generating a pseudo random sequence of a modulation bins, organizing each modulation bin as a series of submodulation bins, thereby forming an extended pseudo random sequence of submodulation bins, releasing the analytes in a series of analyte packets into a Spectrometer, thereby generating an unknown original ion signal vector, detecting the analytes at a detector, and characterizing the sample using the plurality of analyte signal subvectors. The method is advantageously applied to an Ion Mobility Spectrometer, and an Ion Mobility Spectrometer interfaced with a Time of Flight Mass Spectrometer.

Belov, Mikhail E. (Richland, WA); Smith, Richard D. (Richland, WA)

2009-06-02

449

The wide-angle neutron spin echo spectrometer project WASP  

SciTech Connect

This paper describes design and optimization for the wide angle spin-echo spectrometer (WASP) presently being planned at the ILL. The spectrometer will be a replacement for the high intensity spectrometer IN11 and will enhance its signal by more than one order of magnitude while maintaining the resolution of the present spectrometer. The paper outlines the magnetic field calculations and the considerations about possible limitations. The projected performance has been verified carefully by Monte Carlo raytracing and Biot-Savart magnetic field calculations. The maximum momentum transfer of the new spectrometer is to be extended to 4 angstroms {sup -1}.

Ehlers, Georg [ORNL

2007-01-01

450

Large-scale calcium metal sample preparation for /sup 41/Ca isotope pre-enrichment and AMS (accelerator mass spectrometer). [Accelerator mass spectrometer  

SciTech Connect

Large quantities of high-purity Ca metal were successfully prepared and used in the Oak Ridge Calutron and subsequent AMS (accelerator mass spectrometer) measurements at Argonne National Laboratory. The high purity could be partly due to the pureness of the original source material for CaCO/sub 3/ but mostly due to the method of Ca metal reduction involved. A further indication that this is very high quality Ca metal was obtained from the Calutron from enrichment runs where the efficiency seems about a factor of 1.5 to 1.7 better than for the commercial Ca metal generally used.

Henning, W.; Liu, Z.; Lucas, H.F.; Thomas, G.E.; Adair, H.L.; Grisham, W.B.

1986-01-01

451

ScanSpec: an imaging FTIR spectrometer  

NASA Astrophysics Data System (ADS)

The demand for hyperspectral imagers for research has increased in order to match the performance of new sensors for military applications. These work in several spectral bands and targets and backgrounds need to be characterized both spatially and spectrally to enable efficient signature analysis. Another task for a hyperspectral research imager is to acquire hyperspectral data to be able to study new hyperspectral signal processing techniques to detect, classify, and identify targets. This paper describes how a hyperspectral IR imager was developed based on an FTIR spectrometer at the Defence Research Establishment (FOA) in Linkoping, Sweden. The system, called ScanSpec, consists of a fast FTIR spectrometer from Bomem (MR254), an image-scanning mirror device with controlling electronics, and software for data collection and image forming. The spectrometer itself has not been modified. The paper also contains a performance evaluation with NESR NEDT, and MRTD analysis. Finally, some examples of hyperspectral results from field trials are presented: maritime background and remote gas detection.

Nelsson, Claes; Lundberg, Frans; Nilsson, Paer; Berglund, Mattias

2000-07-01

452

Development of a segmented fast neutron spectrometer  

NASA Astrophysics Data System (ADS)

We discuss the development of a spectrometer based on full energy absorption using liquid scintillator doped with enriched 6Li. Of specific interest, the spectrometer is expected to have good pulse height resolution, estimated to lie in the range 10 15% for 14-MeV neutrons. It should be sensitive to flux rates from 10-6 cm-2 s-1 to 106 cm-2 s-1 above a threshold of 500 keV in an uncorrelated ? background of up to 104 s-1. We have constructed a pilot version of the detector using undoped liquid scintillator, and we report its present status. The detector’s efficiency is determined by the volume of the scintillator (˜1.21) and is estimated to be 0.2 0.5% for 3-MeV neutrons. The good pulse height resolution is achieved by compensation of the nonlinear light yield of the scintillator due to the use of optically separated segments, which collect scintillations from each recoil proton separately. We demonstrate here the response of the detector to neutrons from a Pu-?-Be source, whose energies range up to 10 MeV. Initial testing indicates a low threshold (?600 keV) and good spectral response after requiring a multiplicity of three segments. Such a spectrometer has applications for low-background experiments in fundamental physics research, characterizations of neutron flux in space, and the health physics community.

Abdurashitov, J. N.; Gavrin, V. N.; Matushko, V. L.; Nico, J. S.; Shikhin, A. A.; Thompson, A. K.; Veretenkin, I. E.; Yants, V. E.

2007-01-01

453

The compact neutron spectrometer at ASDEX Upgrade  

SciTech Connect

The first neutron spectrometer of ASDEX Upgrade (AUG) was installed in November 2008. It is a compact neutron spectrometer (CNS) based on a BC501A liquid scintillating detector, which can simultaneously measure 2.45-MeV and 14-MeV neutrons emitted from deuterium (D) plasmas and {gamma} radiation. The scintillating detector is coupled to a digital pulse shape discrimination data acquisition (DPSD) system capable of count rates up to 10{sup 6} s{sup -1}. The DPSD system can operate in acquisition and processing mode. With the latter n-{gamma} discrimination is performed off-line based on the two-gate method. The paper describes the tests of the CNS and its installation at AUG. The neutron emission from the D plasma measured during a discharge with high auxiliary heating power was used to validate the CNS performance. The study of the optimal settings for the DPSD data processing to maximize the n-{gamma} discrimination capability of the CNS is reported. The CNS measured both 2.45-MeV and 14-MeV neutrons emitted in AUG D plasmas with a maximum count rate of 5.4 x10{sup 5} s{sup -1} (>10 times higher than similar spectrometers previously achieved) with an efficiency of 9.3 x 10{sup -10} events per AUG neutron.

Giacomelli, L.; Zimbal, A.; Tittelmeier, K.; Schuhmacher, H. [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Tardini, G.; Neu, R. [Max Planck Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); Collaboration: ASDEX Upgrade Team

2011-12-15

454

Advances in miniature spectrometer and sensor development  

NASA Astrophysics Data System (ADS)

Miniaturization and cost reduction of spectrometer and sensor technologies has great potential to open up new applications areas and business opportunities for analytical technology in hand held, mobile and on-line applications. Advances in microfabrication have resulted in high-performance MEMS and MOEMS devices for spectrometer applications. Many other enabling technologies are useful for miniature analytical solutions, such as silicon photonics, nanoimprint lithography (NIL), system-on-chip, system-on-package techniques for integration of electronics and photonics, 3D printing, powerful embedded computing platforms, networked solutions as well as advances in chemometrics modeling. This paper will summarize recent work on spectrometer and sensor miniaturization at VTT Technical Research Centre of Finland. Fabry-Perot interferometer (FPI) tunable filter technology has been developed in two technical versions: Piezoactuated FPIs have been applied in miniature hyperspectral imaging needs in light weight UAV and nanosatellite applications, chemical imaging as well as medical applications. Microfabricated MOEMS FPIs have been developed as cost-effective sensor platforms for visible, NIR and IR applications. Further examples of sensor miniaturization will be discussed, including system-on-package sensor head for mid-IR gas analyzer, roll-to-roll printed Surface Enhanced Raman Scattering (SERS) technology as well as UV imprinted waveguide sensor for formaldehyde detection.

Malinen, Jouko; Rissanen, Anna; Saari, Heikki; Karioja, Pentti; Karppinen, Mikko; Aalto, Timo; Tukkiniemi, Kari

2014-05-01

455

Cooled grating infrared spectrometer for astronomical observations  

NASA Technical Reports Server (NTRS)

A liquid helium-cooled infrared spectrometer for the 16 to 50 micron range is described. The instrument has six detectors, three each of Si:Sb and Ge:Ga and two diffraction gratings mounted back-to-back. Cold preoptics are used to match the spectrometer to the telescope. In its nominal configuration the system resolution is 0.03 micron from 16 to 30 microns and 0.07 micron from 28 to 50 microns. A cooled filter wheel is used to change order sorting filters. The gratings are driven by a steel band and gear train operating at 4 K. The detector outputs are amplified by a TIA, employing a matched pair of JFETs operating at 70 K inside the dewar. The external warm electronics include a gain stage for the TIA and dc-coupled gating circuit to remove charged-particle (cosmic-ray secondary)-induced noise spikes. The gating circuit reduces the overall system noise by a factor of two when the spectrometer is used on NASA's Kuiper Airborne Observatory. Sample spectra are presented and the deglitcher performance is illustrated.

Houck, J. R.; Gull, G. E.

1983-01-01

456

Prismatic analyser concept for neutron spectrometers  

NASA Astrophysics Data System (ADS)

Developments in modern neutron spectroscopy have led to typical sample sizes decreasing from few cm to several mm in diameter samples. We demonstrate how small samples together with the right choice of analyser and detector components makes distance collimation an important concept in crystal analyser spectrometers. We further show that this opens new possibilities where neutrons with different energies are reflected by the same analyser but counted in different detectors, thus improving both energy resolution and total count rate compared to conventional spectrometers. The technique can readily be combined with advanced focussing geometries and with multiplexing instrument designs. We present a combination of simulations and data showing three different energies simultaneously reflected from one analyser. Experiments were performed on a cold triple axis instrument and on a prototype inverse geometry Time-of-flight spectrometer installed at PSI, Switzerland, and shows excellent agreement with the predictions. Typical improvements will be 2.0 times finer resolution and a factor of 1.9 in flux gain compared to a focussing Rowland geometry, or of 3.3 times finer resolution and a factor of 2.4 in flux gain compared to a single flat analyser slab.

Birk, Jonas O.; Markó, Márton; Freeman, Paul G.; Jacobsen, Johan; Hansen, Rasmus L.; Christensen, Niels B.; Niedermayer, Christof; Mânsson, Martin; Rønnow, Henrik M.; Lefmann, Kim

2014-11-01

457

Multislit optimized spectrometer: fabrication and assembly update  

NASA Astrophysics Data System (ADS)

The NASA ESTO funded Multi-slit Optimized Spectrometer (MOS) Instrument Incubator Program will advance a spatial multiplexing spectrometer for coastal ocean remote sensing from lab demonstration to flight like environment testing. Vibration testing to meet the GEVS requirements for a geostationary orbit launch will be performed. The multiple slit design reduces the required telescope aperture leading to mass and volume reductions over conventional spectrometers when applied to the GEO-CAPE oceans mission. The MOS program is entering year 3 of the 3-year program where assembly and test activities will demonstrate the performance of the MOS concept. This paper discusses the instrument design, fabrication and assembly. It outlines the test plan to realize a technology readiness level of 6. Testing focuses on characterizing radiometric impacts of the multiple slit images multiplexed onto a common focal plane, and assesses the resulting uncertainties imparted to the ocean color data products. The MOS instrument implementation for GEO-CAPE provides system benefits that can lead to cost savings and risk reduction while meeting the science objectives of understanding the dynamic coastal ocean environment.

Valle, Tim; Hardesty, Chuck; Good, William; Seckar, Chris; Shea, Don; Spuhler, Peter; Davis, Curtiss O.; Tufillaro, Nicholas

2013-09-01

458

Mathematical Simulation for Integrated Linear Fresnel Spectrometer Chip  

NASA Technical Reports Server (NTRS)

A miniaturized solid-state optical spectrometer chip was designed with a linear gradient-gap Fresnel grating which was mounted perpendicularly to a sensor array surface and simulated for its performance and functionality. Unlike common spectrometers which are based on Fraunhoffer diffraction with a regular periodic line grating, the new linear gradient grating Fresnel spectrometer chip can be miniaturized to a much smaller form-factor into the Fresnel regime exceeding the limit of conventional spectrometers. This mathematical calculation shows that building a tiny motionless multi-pixel microspectrometer chip which is smaller than 1 cubic millimter of optical path volume is possible. The new Fresnel spectrometer chip is proportional to the energy scale (hc/lambda), while the conventional spectrometers are proportional to the wavelength scale (lambda). We report the theoretical optical working principle and new data collection algorithm of the new Fresnel spectrometer to build a compact integrated optical chip.

Park, Yeonjoon; Yoon, Hargoon; Lee, Uhn; King, Glen C.; Choi, Sang H.