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Sample records for 4pi ge spectrometer

  1. A 4. pi. tracking TPC magnetic spectrometer for RHIC

    SciTech Connect

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

    1990-01-01

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

  2. An approximately 4. pi. tracking magnetic spectrometer for RHIC

    SciTech Connect

    Not Available

    1987-01-01

    A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) is proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low rapidity quark-gluon plasma.

  3. A 4. pi. tracking magnetic spectrometer for RHIC

    SciTech Connect

    Lindenbaum, S.J.

    1988-01-01

    A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) was previously proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low cm rapidity quark-gluon plasma. Experimental progress in the successful performance of a TPC developed for AGS E-810 is reported. We have also included typical results of our event generator which contains an interface of an improved HIJET and a plasma bubble model. Typical plasma signals one can expect from this model are presented. 4 refs., 9 figs.

  4. 4. pi. physics. [/sup 40/Ar + KCl, 0. 4 to 1. 8 GeV/A

    SciTech Connect

    Sandoval, A.

    1980-03-01

    Exclusive ..pi../sup -/ and charged-particle production in collisions of /sup 40/Ar on KCl are studied at incident energies from 0.4 to 1.8 GeV/A. The correlation between the ..pi../sup -/ and the total charged particle multiplicity confines the reaction along a narrow ridge with no exotic islands of pion production. For high multiplicities the system reaches the total disintegration of target and projectile into singly charged fragments and pions. Every 200 MeV/A datum was taken with a central and inelastic trigger. For central collisions the mean ..pi../sup -/ multiplicity increases linearly with the bombarding energy with no marked discontinuities due to the ..delta..(3,3) resonance. At 1.8 GeV/A evidence for nonthermal ..pi../sup -/ production in central collisions is found. The total c.m. energy in ..pi../sup -/ shows linear dependence on the ..pi../sup -/ multiplicity with a slope of epsilon = 300 MeV/..pi../sup -/. Strange particle production in the central collision of 1.8 GeV/A Ar on KCl is seen. 8 figures.

  5. 4{pi} studies of the 1.8{endash}4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. I. Energy deposition

    SciTech Connect

    Morley, K.B.; Kwiatkowski, K.; Bracken, D.S.; Renshaw Foxford, E.; Viola, V.E.; Woo, L.W.; Yoder, N.R.; Legrain, R.; Pollacco, E.C.; Volant, C.; Korteling, R.G.; Breuer, H.; Brzychczyk, J.

    1996-08-01

    The Indiana Silicon Sphere 4{pi} detector has been used to measure light-charged particles and intermediate-mass fragments (IMFs) emitted in the 18{endash}4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. Ejectile multiplicity and total event kinetic energy distributions scale systematically with projectile energy and target mass, except for the {sup nat}Ag target at 3.6 and 4.8 GeV. For this system, a saturation in deposition energy is indicated by the data, suggesting the upper projectile energy for stopping has been reached. Maximum deposition energies of {approximately}950 MeV for the {sup nat}Ag target and {approximately}1600 MeV for the {sup 197}Au target are inferred from the data. The results also demonstrate the importance of accounting for fast cascade processes in defining the excitation energy of the targetlike residue. Correlations between various observables and the average IMF multiplicity indicate that the total thermal energy and total observed charge provide useful gauges of the excitation energy of the fragmenting system. Comparison of the experimental distributions with intranuclear cascade predictions shows qualitative agreement. {copyright} {ital 1996 The American Physical Society.}

  6. 4Pi-RESOLFT nanoscopy.

    PubMed

    Böhm, Ulrike; Hell, Stefan W; Schmidt, Roman

    2016-01-01

    By enlarging the aperture along the optic axis, the coherent utilization of opposing objective lenses (4Pi arrangement) has the potential to offer the sharpest and most light-efficient point-spread-functions in three-dimensional (3D) far-field fluorescence nanoscopy. However, to obtain unambiguous images, the signal has to be discriminated against contributions from lobes above and below the focal plane, which has tentatively limited 4Pi arrangements to imaging samples with controllable optical conditions. Here we apply the 4Pi scheme to RESOLFT nanoscopy using two-photon absorption for the on-switching of fluorescent proteins. We show that in this combination, the lobes are so low that low-light level, 3D nanoscale imaging of living cells becomes possible. Our method thus offers robust access to densely packed, axially extended cellular regions that have been notoriously difficult to super-resolve. Our approach also entails a fluorescence read-out scheme that translates molecular sensitivity to local off-switching rates into improved signal-to-noise ratio and resolution. PMID:26833381

  7. 4Pi-RESOLFT nanoscopy

    NASA Astrophysics Data System (ADS)

    Böhm, Ulrike; Hell, Stefan W.; Schmidt, Roman

    2016-02-01

    By enlarging the aperture along the optic axis, the coherent utilization of opposing objective lenses (4Pi arrangement) has the potential to offer the sharpest and most light-efficient point-spread-functions in three-dimensional (3D) far-field fluorescence nanoscopy. However, to obtain unambiguous images, the signal has to be discriminated against contributions from lobes above and below the focal plane, which has tentatively limited 4Pi arrangements to imaging samples with controllable optical conditions. Here we apply the 4Pi scheme to RESOLFT nanoscopy using two-photon absorption for the on-switching of fluorescent proteins. We show that in this combination, the lobes are so low that low-light level, 3D nanoscale imaging of living cells becomes possible. Our method thus offers robust access to densely packed, axially extended cellular regions that have been notoriously difficult to super-resolve. Our approach also entails a fluorescence read-out scheme that translates molecular sensitivity to local off-switching rates into improved signal-to-noise ratio and resolution.

  8. 4Pi-RESOLFT nanoscopy

    PubMed Central

    Böhm, Ulrike; Hell, Stefan W.; Schmidt, Roman

    2016-01-01

    By enlarging the aperture along the optic axis, the coherent utilization of opposing objective lenses (4Pi arrangement) has the potential to offer the sharpest and most light-efficient point-spread-functions in three-dimensional (3D) far-field fluorescence nanoscopy. However, to obtain unambiguous images, the signal has to be discriminated against contributions from lobes above and below the focal plane, which has tentatively limited 4Pi arrangements to imaging samples with controllable optical conditions. Here we apply the 4Pi scheme to RESOLFT nanoscopy using two-photon absorption for the on-switching of fluorescent proteins. We show that in this combination, the lobes are so low that low-light level, 3D nanoscale imaging of living cells becomes possible. Our method thus offers robust access to densely packed, axially extended cellular regions that have been notoriously difficult to super-resolve. Our approach also entails a fluorescence read-out scheme that translates molecular sensitivity to local off-switching rates into improved signal-to-noise ratio and resolution. PMID:26833381

  9. 4. pi. physics with the plastic ball

    SciTech Connect

    Gutbrod, H.H.; Loehner, H.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G.; Warwick, A.; Weik, F.; Wieman, H.

    1982-10-01

    4 ..pi.. data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density.

  10. GIOVE, a shallow laboratory Ge-spectrometer with 100 μBq/kg sensitivity

    SciTech Connect

    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.

    2013-08-08

    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){sup −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.

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

    SciTech Connect

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

    2008-05-01

    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.

  12. The Diogene 4 pi detector at Saturne

    NASA Technical Reports Server (NTRS)

    Alard, J. P.; Arnold, J.; Augerat, J.; Babinet, R.; Bastid, N.; Brochard, F.; Costilhes, J. P.; Crouau, M.; De Marco, N.; Drouet, M.; Dupieux, P.; Fanet, H.; Fodor, Z.; Fraysse, L.; Girard, J.; Gorodetzky, P.; Gosset, J.; Laspalles, C.; Lemaire, M. C.; L'Hote, D.; Lucas, B.; Montarou, G.; Papineau, A.; Parizet, M. J.; Schimmerling, W.

    1987-01-01

    Diogene, an electronic 4 pi detector, has been built and installed at the Saturne synchrotron in Saclay. The forward angular range (0 degree-6 degrees) is covered by 48 time-of-flight scintillator telescopes that provide charge identification. The trajectories of fragments emitted at larger angles are recorded in a cylindrical 0.4-m3 Pictorial Drift Chamber (PDC) surrounding the target. The PDC is inside a 1-T magnetic field; the axis of the PDC cylinder and the magnetic field are parallel to the beam. Good identification has been obtained for both positive and negative pi mesons and for hydrogen and helium isotopes. Multiplicities in relativistic nucleus-nucleus reactions up to 40 have been detected, limited mainly by the present electronics.

  13. GeMini: The Next-Generation Mechanically-Cooled Germanium Spectrometer

    SciTech Connect

    Burks, M

    2008-11-12

    The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (MINIature GErmanium spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. Intended applications include short-notice inspections, border patrol, port monitoring and emergency response, where positive nuclide identification of radioactive materials is required but power and liquid cryogen are not easily available. GeMini weighs 2.75 kg for the basic instrument and 4.5 kg for the full instrument including user interface and ruggedized hermetic packaging. It is very low power allowing it to operate for 10 hours on a single set of rechargeable batteries. This instrument employs technology adapted from the gamma-ray spectrometer currently flying on NASA's Mercury MESSENGER spacecraft. Specifically, infrared shielding techniques allow for a vast reduction of thermal load. This in turn allows for a smaller, lighter-weight design, well-suited for a hand-held instrument. Three working prototypes have been built and tested in the lab. The measured energy resolution is 3 keV fwhm at 662 keV gamma-rays. This paper will focus on the design and performance of the instrument.

  14. GeMini: The Next Generation Mechanically-Cooled Germanium Spectrometer

    SciTech Connect

    Burks, M

    2008-06-13

    The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (GErmanium MINIature spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. Intended applications include short-notice and surprise inspections where positive nuclide identification of radioactive materials is required. GeMini weighs 2.75 kg (6 lbs) total including the detector, cryostat, cryocooler, batteries, electronics and readout. It is very low power allowing it to operate for 10 hours on a single set of rechargeable batteries. This instrument employs technology adapted from the gamma-ray spectrometer currently flying on NASA's Mercury MESSENGER spacecraft. Specifically, infrared shielding techniques allow for a vast reduction of thermal load. This in turn allows for a smaller, lighter-weight design, well-suited for a hand-held instrument. Two working prototypes have been built and tested in the lab. The target energy resolution is 3 keV fwhm or better for 1332 keV gamma-rays. The detectors currently achieve around 4.5 keV resolution, which is slightly higher than our goal due to microphonic noise. Our present work focuses on improving the resolution through mechanical and electronic means of reducing the microphonic noise. This paper will focus on the performance of the instrument and its applicability for inspectors in the field.

  15. Calibration of Ge gamma-ray spectrometers for complex sample geometries and matrices

    NASA Astrophysics Data System (ADS)

    Semkow, T. M.; Bradt, C. J.; Beach, S. E.; Haines, D. K.; Khan, A. J.; Bari, A.; Torres, M. A.; Marrantino, J. C.; Syed, U.-F.; Kitto, M. E.; Hoffman, T. J.; Curtis, P.

    2015-11-01

    A comprehensive study of the efficiency calibration and calibration verification of Ge gamma-ray spectrometers was performed using semi-empirical, computational Monte-Carlo (MC), and transfer methods. The aim of this study was to evaluate the accuracy of the quantification of gamma-emitting radionuclides in complex matrices normally encountered in environmental and food samples. A wide range of gamma energies from 59.5 to 1836.0 keV and geometries from a 10-mL jar to 1.4-L Marinelli beaker were studied on four Ge spectrometers with the relative efficiencies between 102% and 140%. Density and coincidence summing corrections were applied. Innovative techniques were developed for the preparation of artificial complex matrices from materials such as acidified water, polystyrene, ethanol, sugar, and sand, resulting in the densities ranging from 0.3655 to 2.164 g cm-3. They were spiked with gamma activity traceable to international standards and used for calibration verifications. A quantitative method of tuning MC calculations to experiment was developed based on a multidimensional chi-square paraboloid.

  16. Development of a Multi-GeV spectrometer for laser-plasma experiment at FLAME

    NASA Astrophysics Data System (ADS)

    Valente, P.; Anelli, F.; Bacci, A.; Batani, D.; Bellaveglia, M.; Benocci, R.; Benedetti, C.; Cacciotti, L.; Cecchetti, C. A.; Clozza, A.; Cultrera, L.; Di Pirro, G.; Drenska, N.; Faccini, R.; Ferrario, M.; Filippetto, D.; Fioravanti, S.; Gallo, A.; Gamucci, A.; Gatti, G.; Ghigo, A.; Giulietti, A.; Giulietti, D.; Gizzi, L. A.; Koester, P.; Labate, L.; Levato, T.; Lollo, V.; Londrillo, P.; Martellotti, S.; Pace, E.; Pathak, N.; Rossi, A.; Tani, F.; Serafini, L.; Turchetti, G.; Vaccarezza, C.

    2011-10-01

    The advance in laser-plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular, the upcoming experiments with the 250 TW laser at the FLAME facility of the INFN Laboratori Nazionali di Frascati, will enter the GeV regime with more than 100 pC of electrons. At the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need for developing a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV), with still unknown angular divergences. Within the PlasmonX experiment at FLAME, a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence, present challenges in the design and construction of such a device. We present the design considerations for this spectrometer that lead to the use of scintillating fibers, multichannel photo-multipliers and a multiplexing electronics, a combination which is innovative in the field. We also present the experimental results obtained with a high intensity electron beam performed on a prototype at the LNF beam test facility.

  17. Analysis of Superconducting Dipole Coil of 11 GeV Super High Momentum Spectrometer

    SciTech Connect

    Sun, Eric; Cheng, Gary; Lassiter, Steve R.; Brindza, Paul D.; Fowler, Michael J.

    2015-06-01

    Jefferson Lab is constructing five Super High Momentum Spectrometer (SHMS) superconducting magnets for the 12 GeV Upgrade. This paper reports measured coil material properties and the results of the extensive finite element analysis (FEA) for the dipole coil. To properly define the smeared orthotropic material of the coil, a detailed coil model is set up to compute material parameters because not all parameters were measured. Stress and strain acceptance criteria are discussed. Eight load steps are defined. The preheat temperature of the force collar is optimized under two loading scenarios so that the positive pressure between the inner coil and central spacer is maintained while there is not too much squeeze to the coil.

  18. Estimation method of planetary fast neutron flux by a Ge gamma-ray spectrometer

    NASA Astrophysics Data System (ADS)

    Hareyama, M.; Fujibayashi, Y.; Yamashita, Y.; Karouji, Y.; Nagaoka, H.; Kobayashi, S.; Reedy, R. C.; Gasnault, O.; Forni, O.; d'Uston, C.; Kim, K. J.; Hasebe, N.

    2016-08-01

    An intensity map of lunar fast neutrons (LFNs) and their temporal variation has been estimated by fitting "sawtooth" peaks in the energy spectra of lunar gamma rays observed by the Kaguya (SELENE) Gamma Ray Spectrometer (GRS) consisting of a high-purity germanium (HPGe) detector with a BGO scintillator. While an ordinary peak in the spectrum is produced by only gamma ray lines, the sawtooth peak is produced by gamma ray lines and recoil nuclei in the detector by Ge(n ,n‧ γ) reaction. We develop a model for the shape of the sawtooth peak and apply it to fit sawtooth peaks together with ordinary peaks in actual observed spectra on the Moon. The temporal variation of LFNs is synchronous with that of galactic cosmic rays (GCRs), and the global distribution of fast neutrons on the lunar surface agrees well with the past observation reported by the Neutron Spectrometer aboard Lunar Prospector. Based on these results, a new method is established to estimate the flux of fast neutrons by fitting sawtooth peaks on the gamma ray spectrum observed by the HPGe detector.

  19. Ge-diode detector combined with crystal-diffraction spectrometer permits high-resolution gamma ray spectroscopy

    NASA Technical Reports Server (NTRS)

    Namenson, A. I.; Smither, R. K.

    1969-01-01

    Crystal-diffraction spectrometer, combined with a lithium-drifted Ge-diode detector, performs high-resolution gamma ray spectroscopy on the complicated neutron-capture gamma ray spectra. The system is most useful in the 1-3 MeV energy range and improves the signal to background ratio.

  20. A new look at reaction mechanisms with 4. pi. charged-particle and neutron multiplicity measurements

    SciTech Connect

    Sarantites, D.G.; Semkow, T.M.; Sobotka, L.G.; Abenante, V.; Li, Z.; Majka, Z.; Nicolis, N.G.; Stracener, D.W.; Hensley, D.C.; Beene, J.R.

    1987-01-01

    We have studied the excitation of target-like fragments produced in the reactions of 331.9 MeV /sup 28/Si + /sup 181/Ta. The light charged particles and intermediate mass fragments were detected in a small, highly segmented 4..pi.. phoswich detector system placed inside the spin spectrometer, a 4..pi.. NaI array which served as a neutron and ..gamma..-ray detector. All target emissions indicate that excitation ceases to increase with decreasing projectile-like fragment energy, as it should if the primary reaction is binary. Non-equilibrium neutron, proton and ..cap alpha..-particle emission and projectile fragmentation conspire and limit the conversion of kinetic energy into target excitation. This effect is more pronounced for PLF away from the injection point and for the largest kinetic energy losses. 8 refs., 10 figs.

  1. 4Pi Spectral Self-interference Fluorescence Microscopy

    NASA Astrophysics Data System (ADS)

    Dogan, Mehmet; Swan, Anna K.; Unlu, M. Selim; Goldberg, Bennett B.

    2006-03-01

    4Pi fluorescence confocal microscopy [1] improves axial resolution, and Spectral Self-Interference Fluorescence Microscopy (SSFM) [2] provides sub-nanometer localization of fluorescent emitters in biological structures. Here we report on the construction and evaluation of a 4Pi fluorescence confocal microscope and discuss the efforts to combine the high resolution 4Pi technique with SSFM. In the 4Pi microscope, the back focal planes of two opposing high numerical aperture objectives are filled with coherent laser illumination and counter propagating spherical wave fronts form constructive interference at the common focus of two objectives, resulting in an improvement of the axial point spread function (PSF). We characterized the 3-D PSF of the microscope using fluorescent polystyrene beads and fluorescent monolayers. We measured a factor of 3 improvement of the axial PSF compared to a confocal microscope. [1] S. W. Hell et al. J.Opt.Soc.Am. A Vol.9, No.12, pp.2159 (1992) [2] A. K. Swan et al. IEEE JSTQE Vol. 9, No. 2, pp. 294 (2003)

  2. Test of a Silica Aerogel Threshold Cherenkov Counter for the TJNAF Hall A Spectrometers with 1-GeC/c - 4-GeV/c Particles

    SciTech Connect

    R. Perrino; Luigi Lagamba; Evaristo Cisbani; Stefano Colilli; Riccardo Crateri; Raffaele De Leo; Salvatore Frullani; Franco Garibaldi; Fausto Giuliani; Massimo Gricia; Mauro Iodice; Antonio Leone; Maurizio Lucentini; A. Mostarda; E. Nappi; L. Pierangeli; Fabio Santavenere

    1998-09-01

    The silica aerogel threshold Cherenkov counter for the Jefferson Lab Hall A spectrometers has been tested at CERN with a beam of positrons, pions and protons in order to characterize its efficiencies to particle detection in the 1 to 4 GeV/c momentum range. A detection efficiency to particles above the Cherenkov threshold (e{sup +} and {pi}{sup +}) greater than 95% and to particles below the threshold (p) of about 5% has been quoted in the whole momentum range explored. The detection efficiency to protons is due both to induced {delta}-rays production (3.5%), and to accidentals due to the high counting rate.

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

    NASA Astrophysics Data System (ADS)

    Rustamov, Anar

    2010-08-01

    We present the inclusive di-electron invariant-mass spectrum from p+p interactions at 3.5 GeV kinetic beam energy. It is a very important reference for the study of vector meson production off the nucleus, recently investigated by HADES in p+93Nb reactions at the same beam energy. Up to invariant masses of 0.6 GeV/c2 the main contributions to the e+e- spectrum are π0, η, ω and Δ Dalitz decays. In the vector-meson region a clear peak corresponding to the ω direct decay is reconstructed with ≈2% mass resolution. Subtracting this peak from the spectrum allows to investigate additional sources, in particular the ρ meson. Indeed, the latest results from HSD and UrQMD calculations show different distributions for the shape of the ρ meson at these energies. Therefore it is important to experimentally understand the production mechanism of the ρ meson in elementary reactions. Besides the spectral shape of the mesons, their inclusive production cross sections are also not known at these energies. Due to the large and flat acceptance of the HADES spectrometer for e+e- masses above 0.2 GeV/c2 and for PT<1GeV/c, acceptance corrections are to a large extent model independent. This allows us to extract the preliminary inclusive cross section values for the meson productions at these energies.

  4. Continuous fluorescence microphotolysis and correlation spectroscopy using 4Pi microscopy.

    PubMed

    Arkhipov, Anton; Hüve, Jana; Kahms, Martin; Peters, Reiner; Schulten, Klaus

    2007-12-01

    Continuous fluorescence microphotolysis (CFM) and fluorescence correlation spectroscopy (FCS) permit measurement of molecular mobility and association reactions in single living cells. CFM and FCS complement each other ideally and can be realized using identical equipment. So far, the spatial resolution of CFM and FCS was restricted by the resolution of the light microscope to the micrometer scale. However, cellular functions generally occur on the nanometer scale. Here, we develop the theoretical and computational framework for CFM and FCS experiments using 4Pi microscopy, which features an axial resolution of approximately 100 nm. The framework, taking the actual 4Pi point spread function of the instrument into account, was validated by measurements on model systems, employing 4Pi conditions or normal confocal conditions together with either single- or two-photon excitation. In all cases experimental data could be well fitted by computed curves for expected diffusion coefficients, even when the signal/noise ratio was small due to the small number of fluorophores involved. PMID:17704168

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

    SciTech Connect

    Rustamov, Anar

    2010-08-05

    We present the inclusive di-electron invariant-mass spectrum from p+p interactions at 3.5 GeV kinetic beam energy. It is a very important reference for the study of vector meson production off the nucleus, recently investigated by HADES in p+{sup 93}Nb reactions at the same beam energy. Up to invariant masses of 0.6 GeV/c{sup 2} the main contributions to the e{sup +}e{sup -} spectrum are {pi}{sup 0},{eta}, {omega} and {Delta} Dalitz decays. In the vector-meson region a clear peak corresponding to the {omega} direct decay is reconstructed with {approx_equal}2% mass resolution. Subtracting this peak from the spectrum allows to investigate additional sources, in particular the {rho} meson. Indeed, the latest results from HSD and UrQMD calculations show different distributions for the shape of the {rho} meson at these energies. Therefore it is important to experimentally understand the production mechanism of the {rho} meson in elementary reactions. Besides the spectral shape of the mesons, their inclusive production cross sections are also not known at these energies. Due to the large and flat acceptance of the HADES spectrometer for e{sup +}e{sup -} masses above 0.2 GeV/c{sup 2} and for P{sub T}<1GeV/c, acceptance corrections are to a large extent model independent. This allows us to extract the preliminary inclusive cross section values for the meson productions at these energies.

  6. Automatic deconvolution in 4Pi-microscopy with variable phase.

    PubMed

    Vicidomini, Giuseppe; Schmidt, Roman; Egner, Alexander; Hell, Stefan; Schönle, Andreas

    2010-05-10

    4Pi-microscopy doubles the aperture of the imaging system by coherent addition of the wavefronts for illumination and/or detection through opposing objective lenses. This improves the axial resolution 3-7 fold, but the raw data usually features ghost images which have to be removed by image reconstruction. This straightforward procedure is sometimes precluded by imperfect alignment of the instrument or a specimen with strong variations of its refractive index, because the image formation process now depends on the space-variant phase difference between the counter-propagating wavefronts. Here we present a computationally fast method of parametric blind deconvolution that allows for automatic and robust simultaneous estimation of both the object and the phase function in such cases. We verify the performance of our approach on both synthetic and real data. Because the method does not require a-priori knowledge of the phase function it is major step towards reliable 4Pi-imaging and automatic image restoration by non-expert users. PMID:20588870

  7. Code CUGEL: A code to unfold Ge(Li) spectrometer polyenergetic gamma photon experimental distributions

    NASA Technical Reports Server (NTRS)

    Steyn, J. J.; Born, U.

    1970-01-01

    A FORTRAN code was developed for the Univac 1108 digital computer to unfold lithium-drifted germanium semiconductor spectrometers, polyenergetic gamma photon experimental distributions. It was designed to analyze the combination continuous and monoenergetic gamma radiation field of radioisotope volumetric sources. The code generates the detector system response matrix function and applies it to monoenergetic spectral components discretely and to the continuum iteratively. It corrects for system drift, source decay, background, and detection efficiency. Results are presented in digital form for differential and integrated photon number and energy distributions, and for exposure dose.

  8. Characterization of Lead Tungstate for Neutral Particle Spectrometer at 12 GeV JLab

    NASA Astrophysics Data System (ADS)

    Runyon, Christian

    2015-10-01

    Precision measurements of the deeply-virtual Compton scattering cross section at different beam energies to extract the real part of the Compton form factor, measurements to push the energy scale of real Compton scattering, and measurements of the basic semi-inclusive neutral-pion cross section in a kinematical region where the QCD factorization scheme is expected to hold all have something in common: the need for detecting neutral particles with high precision and high luminosity. The Neutral Particle Spectrometer (NPS) is a crystal electromagnetic calorimeter preceded by a sweeping magnet to sweep away charged particles. In this presentation I will show the results of PbWO4 crystal quality studies for the NPS. PbWO4 is optimal for the NPS due to its small Moliere radius and radiation hardness. The critical aspect for crystal quality, and thus resolution/precision, is the combination of high light output and radiation hardness, which depend strongly on the manufacturing process. We have tested the performance of PbWO4 crystals, and in particular, measured their light yield, optical transmission, and uniformity and radiation hardness. The homogeneity of the crystal was investigated based on the variation of the transverse optical transmission. Supported in part by NSF-PHY-1306227.

  9. Curved optical tubes in a 4Pi focusing system.

    PubMed

    Yan, Shaohui; Yu, Xianghua; Li, Manman; Yao, Baoli

    2015-08-24

    We demonstrate the possibility of creating curved optical tubes in a 4Pi focusing system. The focal fields of such optical tubes have interesting properties: the energy is concentered in the neighborhood of a prescribed three-dimensional (3D) curve while the cross section is of hollow shape. The creation of these optical tubes is based on the annular focal spot of a vortex beam, which is employed as a building block. An optical tube is thus obtained by covering the central-axis curve of the tube by various such building blocks. Each building block has a certain orientation and position, realized by a rotation plus a certain translation. The spatial spectrum (the input field as well) of the optical tube is obtained by linearly superposing the spectrum of each transformed building block. The curve is rather arbitrary. Three examples of optical tubes: a torus, a solenoid and a trefoil knot are given, showing a good agreement with the expected results. PMID:26368256

  10. Search for a QGP with a TPC spectrometer, and QGP signals predicted by new event generator

    SciTech Connect

    Lindenbaum, S.J.

    1988-12-08

    The BNL/CCNY/Johns Hopkins/Rice Collaboration has developed and successfully tested a TPC Magnetic Spectrometer to search for OGP signals produced by ion beams at AGS. Test data with 14.5 GeV/c /times/ A Oxygen ions incident on a Pb target has been obtained. These include a 78-prong nuclear interaction in the MPS magnet which was pattern recognized with an efficiency approx.75%. A cascade and plasma event generator has also been developed, the predictions of which are used to illustrate how our technique can detect possible plasma signals at AGS and RHIC. A 4..pi.. tracking TPC magnetic spectrometer has been proposed for RHIC. The new event generator predicts striking central rapidity bump QGP signals at RHIC for p, /bar p/, ..pi../sup +-/, K/sup +-/, etc., produced by 100 GeV/c /times/ A Au on Au collisions and these are presented. 2 refs., 13 figs., 1 tab.

  11. Effects of polarization and phase modulation on the focal spot in 4Pi microscopy

    NASA Astrophysics Data System (ADS)

    Liu, Shaocong; You, Shangting; Fang, Yue; Wang, Yifan; Kuang, Cuifang; Liu, Xu

    2016-07-01

    In 4Pi microscopy, the intensity and polarization distributions of the focal spot directly determine the system resolution, influencing its extended applications. This paper illustrates how the focal spot is affected by the polarization and phase modulation of the incident beams. Various combinations of polarization states and phase modulations are considered and their effects on the focal spot are investigated. The optimal configurations for generating a solid spot and a doughnut-shaped spot are proposed. This paper provides the theoretical basis and reference for extended applications, such as super-resolution confocal microscopy, 4Pi microscopy or 4Pi-STED microscopy.

  12. Measuring sin2θw in PV-DIS with the Baseline Spectrometers at JLab 12 GeV

    SciTech Connect

    Reimer, Paul

    2007-07-18

    The couplings of leptons to quarks are fundamental parameters of the electroweak interaction. Within the framework of the Standard Model, these couplings can be related to sin2θw. Parity violation (PV) in deep inelastic scattering (DIS) is proportional to these couplings and hence sensitive sin2θw. PV-DIS, first measured at SLAC in the mid-1970's, was used to establish the Standard Model. The high quality and intensity of the upgraded 11 GeV CEBAF beam at Jefferson Laboratory will make it an ideal tool for PV studies. In DIS the asymmetry from parity violation is large (APV ≈10-4 Q2), allowing precise measurements with modest beam-time. This talk will explore a PV-DIS measurement which can be made using the baseline spectrometers that will exist as part of the 12 GeV JLab upgrade.

  13. Measurement of cross section and electron asymmetry of the p (e(pol), e-prime pi+) n reaction in the Delta(1232) and higher resonances for Q**2 <= 4.9-(GeV/c)**2

    SciTech Connect

    Kijun Park; Inna Aznauryan; Volker Burkert; Wooyoung Kim

    2006-06-01

    The cross section and beam asymmetry were measured in channel of (pol)ep --> e'pi^+n using 5.754 GeV electron beam with CEBAF Large Acceptance Spectrometer(CLAS). This measurement covers 4 pi angular coverage and high Q^2 up to 4.9 GeV^2 under various resonance mass regions. The structure functions sigmaT + epsilonLsigmaL, sigmaTT, sigmaLT and sigmaLT/ were extracted from fit angular distribution of cross section and asymmetry.

  14. Charge exchange dp → (pp)n reaction study at 1.75 A GeV/c by the STRELA spectrometer

    NASA Astrophysics Data System (ADS)

    Basilev, S. N.; Bushuev, Yu. P.; Glagolev, V. V.; Dolgiy, S. A.; Kirillov, D. A.; Kostyaeva, N. V.; Kovalenko, A. D.; Livanov, A. N.; Manyakov, P. K.; Martinská, G.; Mušinský, J.; Piskunov, N. M.; Povtoreiko, A. A.; Rukoyatkin, P. A.; Shindin, R. A.; Sitnik, I. M.; Slepnev, V. M.; Slepnev, I. V.; Urbán, J.

    2016-02-01

    The differential cross sections of the charge exchange reaction dp → (pp)n has been measured at 1.75 GeV/c momentum per nucleon for small transferred momenta using the one arm magnetic spectrometer STRELA at the Nuclotron accelerator. The ratio of the differential cross section of the charge exchange reaction dp → (pp)n to that of the np → pn elementary process is discussed in order to estimate the spin-dependent part of the np → pn charge exchange amplitude on the basis of dp → (pp)n data. The np → pn amplitude turned out to be predominantly spin-dependent.

  15. High Resolution Spectrometer in studies of e/sup +/e/sup -/ annihilation at. sqrt. s = 29 GeV

    SciTech Connect

    Derrick, M.

    1985-05-03

    The High Resolution Spectrometer is a general-purpose spectrometer which measures both charged particles and electromagnetic energy over 90% of the solid angle. The detection elements are in a 1.62-T magnetic field. The detector elements consist of a central drift chamber, an outer drift-chamber system, a barrel shower counter, and an end-cap shower-counter system. The goals of the program of research with the High Resolution Spectrometer include measurements of the electroweak coupling of the quarks and leptons, studies of the strong interactions of the quarks, and search for qualitatively new phenomena. 20 refs., 35 figs. (LEW)

  16. NEPTUN-A spectrometer for measuring the Spin Analyzing Power in p-p elastic scattering at large P2⊥ at 400 GeV (and 3 TeV) at UNK

    NASA Astrophysics Data System (ADS)

    Lin, Ali M. T.

    1995-09-01

    We are constructing the NEPTUN-A spectrometer for measuring the Spin Analyzing Power in p+p↑→p+p at P2⊥=2 to 10 (GeV/c)2 at 400 GeV (or at 3 TeV) when the UNK accelerator in Protvino, Russia, becomes operational. The spectrometer consists of a 55 m long recoil arm with 3 horizontally bending magnets to guide the recoil protons onto a fixed 37° line. Then two vertical dipole magnets bend the protons up by 12° for momentum analysis. The momentum will be measured to an accuracy of 0.1% using chambers. In order to accept a large solid angle, the spectrometer contains a strong-focusing pair of quadrupoles looking at the polarized proton jet target. The forward arm consists of scintillator hodoscopes for measurement of the forward vertical angle. Acceptances and event rates are calculated. The status of the spectrometer is reported.

  17. Composite particle production in relativistic Au+Au collisions at AGS: First results from the E866 forward spectrometer @ 2, 4, and 10.8 A{center_dot}GeV

    SciTech Connect

    Ashktorab, K.

    1996-12-31

    Particle spectra were measured for Au + Au collisions at 2, 4, and 10. 8 A{center_dot}GeV using the E866 spectrometers. Recent results on proton emission and composite particle production form the E866 forward spectrometer data taken in 1994 together with the first results from the 1995/6 AGS running period are presented. Preliminary results indicate a decrease in the coalescence scaling coefficient with increasing projectile energy and centrality.

  18. Optimization of statistical methods for HpGe gamma-ray spectrometer used in wide count rate ranges

    NASA Astrophysics Data System (ADS)

    Gervino, G.; Mana, G.; Palmisano, C.

    2016-07-01

    The need to perform γ-ray measurements with HpGe detectors is a common technique in many fields such as nuclear physics, radiochemistry, nuclear medicine and neutron activation analysis. The use of HpGe detectors is chosen in situations where isotope identification is needed because of their excellent resolution. Our challenge is to obtain the "best" spectroscopy data possible in every measurement situation. "Best" is a combination of statistical (number of counts) and spectral quality (peak, width and position) over a wide range of counting rates. In this framework, we applied Bayesian methods and the Ellipsoidal Nested Sampling (a multidimensional integration technique) to study the most likely distribution for the shape of HpGe spectra. In treating these experiments, the prior information suggests to model the likelihood function with a product of Poisson distributions. We present the efforts that have been done in order to optimize the statistical methods to HpGe detector outputs with the aim to evaluate to a better order of precision the detector efficiency, the absolute measured activity and the spectra background. Reaching a more precise knowledge of statistical and systematic uncertainties for the measured physical observables is the final goal of this research project.

  19. Inclusive π° production in 360 GeV pp interactions using the european hybrid spectrometer

    NASA Astrophysics Data System (ADS)

    Bailly, J. L.; Bartl, W.; Bruyant, F.; Bugg, W. M.; Caso, C.; Contri, R.; Dibon, H.; di Marco, R.; Epp, B.; Ferrando, A.; Fontanelli, F.; Girtler, P.; Gurfu, A.; Hart, E. L.; Herquet, P.; Hrubec, J.; Iga, Y.; Kisteney, E.; Kitamura, S.; Kohli, J. M.; Kohno, H.; Marin, J. C.; Markytan, M.; Mittra, I. S.; Montanet, L.; Neuhofer, G.; Petrovykh, Y.; Plano, R.; Poljakov, B.; Porth, P.; Powell, B.; Pylgroms, B.; Rodrigo, T.; Rogers, A. H.; Salicio, J.; Squarcia, S.; Stamer, P.; Stopchenko, V.; Sudhakar, K.; Trevisan, U.; Willmott, C.; Yamagata, T.; Yarba, V.

    1984-06-01

    The intermediate and forward gamma detectors of EHS are used to reconstruct π°'s produced by 360 GeV/c pp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using the pp forwardbackward symmetry, the inclusive π° production cross section is obtained σ π°=(132±11) mb. The average π° multiplicity is determined as a function of the charged particle multiplicity. The (1-x) dependence is given for different p T regions.

  20. Commissioning of horizontal-bend superconducting magnet for Jefferson Lab's 11-GeV super high momentum spectrometer

    DOE PAGESBeta

    Sun, Eric; Brindza, Paul D.; Lassiter, Steven R.; Fowler, Mike J.; Fenker, Howard C.; DeKamp, Jon C.

    2016-03-02

    Commissioning characteristics of the Superconducting High Momentum Spectrometer (SHMS) Horizontal Bend (HB) magnet was presented. Pre-commissioning peer review of the magnet uncovered issues with eddy currents in the thermal shield, resulting in additional testing and modeling of the magnet. A three-stage test plan was discussed. A solution of using a small dump resistor and a warm thermal shield was presented. Analyses illustrated that it was safe to run the magnet to full test current. As a result, the HB magnet was successfully cooled to 4 K and reached its maximum test current of 4000 A.

  1. Large size GEM for Super Bigbite Spectrometer (SBS) polarimeter for Hall A 12GeV program at JLab

    SciTech Connect

    Gnanvo, Kondo; Liyanage, Nilanga; Nelyubin, Vladimir; Saenboonruang, Kiadtisak; Sacher, Seth; Wojtsekhowski, Bogdan

    2015-05-01

    We report on the R&D effort in the design and construction of a large size GEM chamber for the Proton Polarimeter of the Super Bigbite Spectrometer (SBS) in Hall A at Thomas Jefferson National Laboratory (JLab). The SBS Polarimeter trackers consist of two sets of four large chambers of size 200 cm x 60 cm2. Each chamber is a vertical stack of four GEM modules with an active area of 60 cm x 50 cm. We have built and tested several GEM modules and we describe in this paper the design and construction of the final GEM as well as the preliminary results on performances from tests carried out in our detector lab and with test beams at (Fermilab).

  2. Large size GEM for Super Bigbite Spectrometer (SBS) polarimeter for Hall A 12GeV program at JLab

    DOE PAGESBeta

    Gnanvo, Kondo; Liyanage, Nilanga; Nelyubin, Vladimir; Saenboonruang, Kiadtisak; Sacher, Seth; Wojtsekhowski, Bogdan

    2015-05-01

    We report on the R&D effort in the design and construction of a large size GEM chamber for the Proton Polarimeter of the Super Bigbite Spectrometer (SBS) in Hall A at Thomas Jefferson National Laboratory (JLab). The SBS Polarimeter trackers consist of two sets of four large chambers of size 200 cm x 60 cm2. Each chamber is a vertical stack of four GEM modules with an active area of 60 cm x 50 cm. We have built and tested several GEM modules and we describe in this paper the design and construction of the final GEM as well asmore » the preliminary results on performances from tests carried out in our detector lab and with test beams at (Fermilab).« less

  3. Large size GEM for Super Bigbite Spectrometer (SBS) polarimeter for Hall A 12 GeV program at JLab

    NASA Astrophysics Data System (ADS)

    Gnanvo, Kondo; Liyanage, Nilanga; Nelyubin, Vladimir; Saenboonruang, Kiadtisak; Sacher, Seth; Wojtsekhowski, Bogdan

    2015-05-01

    We report on the R&D effort in the design and construction of a large size Gas Electron Multiplier (GEM) for the Proton Polarimeter Back Tracker (BT) of the Super Bigbite Spectrometer (SBS) in Hall A at Thomas Jefferson National Laboratory (JLab). The SBS BT GEM trackers consist of two sets of five large GEM chambers of size 60×200 cm2. The GEM chamber is a vertical stack of four GEM modules, each with an active area of 60×50 cm2. We have built and tested several prototypes and the construction of GEM modules for SBS BT is ongoing. We describe in this paper the design and construction of the GEM module prototype as well as the preliminary results on performance from tests carried out in our detector lab and during test beam at Fermi National Laboratory (Fermilab).

  4. Taylor series expansion based multidimensional image reconstruction for confocal and 4pi microscopy

    NASA Astrophysics Data System (ADS)

    Dilipkumar, Shilpa; Pratim Mondal, Partha

    2013-08-01

    We propose and experimentally demonstrate a three-dimensional (3D) image reconstruction methodology based on Taylor series approximation (TSA) in a Bayesian image reconstruction formulation. TSA incorporates the requirement of analyticity in the image domain, and acts as a finite impulse response filter. This technique is validated on images obtained from widefield, confocal laser scanning fluorescence microscopy and two-photon excited 4pi (2PE-4pi) fluorescence microscopy. Studies on simulated 3D objects, mitochondria-tagged yeast cells (labeled with Mitotracker Orange) and mitochondrial networks (tagged with Green fluorescent protein) show a signal-to-background improvement of 40% and resolution enhancement from 360 to 240 nm. This technique can easily be extended to other imaging modalities (single plane illumination microscopy (SPIM), individual molecule localization SPIM, stimulated emission depletion microscopy and its variants).

  5. Application of PGNAA for bulk coal samples in a 4pi geometry.

    PubMed

    Borsaru, M; Jecny, Z

    2001-03-01

    A 4pi geometry bulk coal analyser using the Prompt gamma neutron activation analysis (PGNAA) technique was tested in the laboratory. The volume of the bulk samples was 270 litres. A 1.5 microg 252Cf neutron source and a 75 mm x 35 mm dia BGO detector were used for the measurements. The ash, Fe, Si and Al content of coal were determined with good accuracy. PMID:11214889

  6. DANCE : a 4[pi] barium fluoride detector for measuring neutron capture on unstable nuclei /.

    SciTech Connect

    Ullmann, J. L.; Haight, Robert C.; Hunt, L. F.; Reifarth, R.; Rundberg, R. S.; Bredeweg, T. A.; Fowler, Malcolm M.; Miller, G. G.; Heil, M.; Käppeler, F.; Chamberlin, E. P.

    2002-01-01

    Measurements of neutron capture on unstable nuclei are important for studies of s-process nucleosynthesis, nuclear waste transmutation, and stewardship science. A 160-element, 4{pi} barium fluoride detector array, and associated neutron flight path, is being constructed to make capture measurements at the moderated neutron spallation source at LANSCE. Measurements can be made on as little as 1 mg of sample material over energies from near thermal to near 100 keV. The design of the DANCE array is described and neutron flux measurements from flight path commissioning are shown. The array is expected to be complete by the end of 2002.

  7. Detailed angular correlation analysis with 4{pi} spectrometers: Spin determinations and multipolarity mixing measurements in {sup 128}Ba

    SciTech Connect

    Wiedenhoever, I.; Vogel, O.; Klein, H.; Dewald, A.; von Brentano, P.; Gableske, J.; Nicolay, N.; Gelberg, A.; Wiedenhoever, I.; Janssens, R.V.; Carpenter, M.P.; Kruecken, R.; Petkov, P.; Gizon, A.; Gizon, J.; Bazzacco, D.; Rossi Alvarez, C.; Pavan, P.; de Angelis, G.; Lunardi, S.; Napoli, D.R.; Frauendorf, S.; Doenau, F.

    1998-08-01

    We analyze for the first time the full {gamma}{gamma} directional correlations from oriented states (DCO) in an experiment performed with the GASP detector array. Our analysis is based on a transformation of the directional information into expansion coefficients of an orthogonal basis. With this method, which we call SpeeDCO (spectral expansion of DCO), the complete DCO information is concentrated in 12 {gamma}{gamma} coincidence spectra. The analysis is applicable to all detector arrays which uniformly cover the solid angle. We show that the complete DCO information can be used for a reliable and unique determination of spins and multipolarity mixing ratios in weakly populated bands. We were able to establish the spins and the positive parity of the {Delta}I=1 {open_quotes}M1 band{close_quotes} in {sup 128}Ba and multipolarity mixing ratios of nine M1/E2 in-band transitions were derived as well. The measured values are in good agreement with those expected for a high-K rotational band. thinsp thinsp thinsp {copyright} {ital 1998} {ital The American Physical Society}

  8. Simulation of the SAGE spectrometer

    NASA Astrophysics Data System (ADS)

    Cox, D. M.; Konki, J.; Greenlees, P. T.; Hauschild, K.; Herzberg, R.-D.; Pakarinen, J.; Papadakis, P.; Rahkila, P.; Sandzelius, M.; Sorri, J.

    2015-06-01

    The SAGE spectrometer combines a Ge-detector array with a Si detector to allow simultaneous detection of γ-rays and electrons. A comprehensive GEANT4 simulation package of the SAGE spectrometer has been developed with the ability to simulate the expected datasets based on user input files. The measured performance of the spectrometer is compared to the results obtained from the simulations.

  9. First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV.

    PubMed

    Aguilar, M; Alberti, G; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Anderhub, H; Arruda, L; Azzarello, P; Bachlechner, A; Barao, F; Baret, B; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Basili, A; Batalha, L; Bates, J; Battiston, R; Bazo, J; Becker, R; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Berges, P; Bertucci, B; Bigongiari, G; Biland, A; Bindi, V; Bizzaglia, S; Boella, G; de Boer, W; Bollweg, K; Bolmont, J; Borgia, B; Borsini, S; Boschini, M J; Boudoul, G; Bourquin, M; Brun, P; Buénerd, M; Burger, J; Burger, W; Cadoux, F; Cai, X D; Capell, M; Casadei, D; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, C R; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chernoplyiokov, N; Chikanian, A; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Commichau, V; Consolandi, C; Contin, A; Corti, C; Costado Dios, M T; Coste, B; Crespo, D; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirkoz, B; Dennett, P; Derome, L; Di Falco, S; Diao, X H; Diago, A; Djambazov, L; Díaz, C; von Doetinchem, P; Du, W J; Dubois, J M; Duperay, R; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eppling, F J; Eronen, T; van Es, J; Esser, H; Falvard, A; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Flood, K; Foglio, R; Fohey, M; Fopp, S; Fouque, N; Galaktionov, Y; Gallilee, M; Gallin-Martel, L; Gallucci, G; García, B; García, J; García-López, R; García-Tabares, L; Gargiulo, C; Gast, H; Gebauer, I; Gentile, S; Gervasi, M; Gillard, W; Giovacchini, F; Girard, L; Goglov, P; Gong, J; Goy-Henningsen, C; Grandi, D; Graziani, M; Grechko, A; Gross, A; Guerri, I; de la Guía, C; Guo, K H; Habiby, M; Haino, S; Hauler, F; He, Z H; Heil, M; Heilig, J; Hermel, R; Hofer, H; Huang, Z C; Hungerford, W; Incagli, M; Ionica, M; Jacholkowska, A; Jang, W Y; Jinchi, H; Jongmanns, M; Journet, L; Jungermann, L; Karpinski, W; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Koulemzine, A; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Laudi, E; Laurenti, G; Lauritzen, C; Lebedev, A; Lee, M W; Lee, S C; Leluc, C; León Vargas, H; Lepareur, V; Li, J Q; Li, Q; Li, T X; Li, W; Li, Z H; Lipari, P; Lin, C H; Liu, D; Liu, H; Lomtadze, T; Lu, Y S; Lucidi, S; Lübelsmeyer, K; Luo, J Z; Lustermann, W; Lv, S; Madsen, J; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masciocchi, F; Masi, N; Maurin, D; McInturff, A; McIntyre, P; Menchaca-Rocha, A; Meng, Q; Menichelli, M; Mereu, I; Millinger, M; Mo, D C; Molina, M; Mott, P; Mujunen, A; Natale, S; Nemeth, P; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oh, S; Oliva, A; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Park, W H; Pauluzzi, M; Pauss, F; Pauw, A; Pedreschi, E; Pensotti, S; Pereira, R; Perrin, E; Pessina, G; Pierschel, G; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pochon, J; Pohl, M; Poireau, V; Porter, S; Pouxe, J; Putze, A; Quadrani, L; Qi, X N; Rancoita, P G; Rapin, D; Ren, Z L; Ricol, J S; Riihonen, E; Rodríguez, I; Roeser, U; Rosier-Lees, S; Rossi, L; Rozhkov, A; Rozza, D; Sabellek, A; Sagdeev, R; Sandweiss, J; Santos, B; Saouter, P; Sarchioni, M; Schael, S; Schinzel, D; Schmanau, M; Schwering, G; Schulz von Dratzig, A; Scolieri, G; Seo, E S; Shan, B S; Shi, J Y; Shi, Y M; Siedenburg, T; Siedling, R; Son, D; Spada, F; Spinella, F; Steuer, M; Stiff, K; Sun, W; Sun, W H; Sun, X H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tassan-Viol, J; Ting, Samuel C C; Ting, S M; Titus, C; Tomassetti, N; Toral, F; Torsti, J; Tsai, J R; Tutt, J C; Ulbricht, J; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vargas Trevino, M; Vaurynovich, S; Vecchi, M; Vergain, M; Verlaat, B; Vescovi, C; Vialle, J P; Viertel, G; Volpini, G; Wang, D; Wang, N H; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Wallraff, W; Weng, Z L; Willenbrock, M; Wlochal, M; Wu, H; Wu, K Y; Wu, Z S; Xiao, W J; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J G; Zhang, Z; Zhang, M M; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zuccon, P; Zurbach, C

    2013-04-01

    A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena. PMID:25166975

  10. Standardization of (18)F using the 4pi(beta+gamma) integral counting technique.

    PubMed

    Yamada, T; Kawada, Y; Sato, Y; Yunoki, A; Hino, Y

    2008-01-01

    Alpha 4pi(beta+gamma) integral counting technique using a 4pibeta-4pigamma detector configuration was adopted for the standardization of (18)F. In this technique, the beta-detector is composed of two thin plastic scintillators sandwiching the source, coupled with a slender photomultiplier tube. The beta-detector part with the source was inserted into a large well-type NaI(Tl) scintillation detector for gamma-ray detection, making a 4pibeta-4pigamma coincidence counting system. In this work, positron particles were detected with high efficiency in the beta-channel and annihilation quanta were also detected with high efficiency in the 4pigamma channel. The very small inefficiency of the 4pi(beta+gamma) integral counter for the beta-plus branch has been confirmed by EGS5 Monte Carlo simulation. The result using this technique agreed within the uncertainties with the result obtained by the conventional 4pibeta-gamma coincidence counting with the efficiency extrapolation technique using the same detector configuration and a conventional 4pibeta-gamma coincidence counter. PMID:18378155

  11. Search for tau- ---> 4pi- 3pi+ (pi0) nu/tau Decays

    SciTech Connect

    Ter-Antonian, R.; Kass, R.; Allmendinger, T.; Hast, C.; /SLAC

    2005-06-21

    A search for the decay of the {tau} lepton to seven charged pions and at most one {pi}{sup 0} was performed using the BABAR detector at the PEP-II e{sup +}e{sup -} collider. The analysis uses data recorded on and near the {Upsilon}(4S) resonance between 1999 and 2003, a total of 124.3 fb{sup -1}. They observe 7 events with an expected background of 11.9 {+-} 2.2 events and calculate a preliminary upper limit of BR({tau}{sup -} {yields} 4{pi}{sup -} 3{pi}{sup +}({pi}{sup 0}){nu}{sub {tau}}) < 2.7 x 10{sup -7} at 90% CL. This is a significant improvement over the previous limit established by the CLEO Collaboration.

  12. SPEIR: A Ge Compton Camera

    SciTech Connect

    Mihailescu, L; Vetter, K M; Burks, M T; Hull, E L; Craig, W W

    2004-02-11

    The SPEctroscopic Imager for {gamma}-Rays (SPEIR) is a new concept of a compact {gamma}-ray imaging system of high efficiency and spectroscopic resolution with a 4-{pi} field-of-view. The system behind this concept employs double-sided segmented planar Ge detectors accompanied by the use of list-mode photon reconstruction methods to create a sensitive, compact Compton scatter camera.

  13. The SAGE spectrometer

    NASA Astrophysics Data System (ADS)

    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

    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.

  14. Aberration control in 4Pi nanoscopy: definitions, properties, and applications (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hao, Xiang; Allgeyer, Edward S.; Velasco, Mary Grace M.; Booth, Martin J.; Bewersdorf, Joerg

    2016-03-01

    The development of fluorescence microscopy, which allows live-cell imaging with high labeling specificity, has made the visualization of cellular architecture routine. However, for centuries, the spatial resolution of optical microscopy was fundamentally limited by diffraction. The past two decades have seen a revolution in far-field optical nanoscopy (or "super-resolution" microscopy). The best 3D resolution is achieved by optical nanoscopes like the isoSTED or the iPALM/4Pi-SMS, which utilize two opposing objective lenses in a coherent manner. These system are, however, also more complex and the required interference conditions demand precise aberration control. Our research involves developing novel adaptive optics techniques that enable high spatial and temporal resolution imaging for biological applications. In this talk, we will discuss how adaptive optics can enhance dual-objective lens nanoscopes. We will demonstrate how adaptive optics devices provide unprecedented freedom to manipulate the light field in isoSTED nanoscopy, allow to realize automatic beam alignment, suppress the inherent side-lobes of the point-spread function, and dynamically compensate for sample-induced aberrations. We will present both the theoretical groundwork and the experimental confirmations.

  15. The data acquisition and control system for the 4{pi} detector CHIMERA

    SciTech Connect

    Aiello, S.; Anzalone, A.; Cardella, G.

    1998-08-01

    CHIMERA (Charged Heavy Ions Mass and Energy Resolving Array), a new 4{pi} detector for charged particles is under development at various sites of the Istituto Nazionale di Fisica Nucleare. This paper describes the new data acquisition system built to handle the signals coming out from the detector with a rate up to 1 kHz on almost 5000 electronic channels. The required average throughput for the system is in the order of the 1 MB/s. The used converters allow double-range conversion on 15 bits, in less than 50 {micro}s for all the 64 channels. The FDL link connects the different VME 9U crates performing a programmable hardware readout with a rate up to 100 MB/s. It uses a fast hardware protocol (Sparse Data Scan) to read the data buffers and send them to a FIC 8243 CPU board. A FIC 8243 dual-processor board forwards data (through Ethernet) to the analysis station (266 Mhz Digital AlphaStation or Sun Sparcstation). A DLT (Digital Linear Tape) unit connected to analysis station is used to store data. The new data acquisition system has been tested under beam conditions at the Laboratorio Nazionale del Sud (Catania, Italy) and at GANIL (Caen, France).

  16. A PbWO4-based Neutral Particle Spectrometer in Hall C at 12 GeV JLab

    SciTech Connect

    Horn, Tanja

    2015-02-01

    The Neutral Particle Spectrometer is a standalone electromagnetic calorimeter capable of detecting high energy photons from, for instance, DVCS or π0 decay with good energy and spatial resolution in a high rate environment. It can be used together with the Hall C high-momentum spectrometers for a suite of experiments with the underlying scientific objective of studying quark dynamics through exclusive and semi-inclusive reactions.

  17. A Comparison of 2pi and 4pi Photometric Testing of Directional and Omnidirectional Sources in an Integrating Sphere

    SciTech Connect

    Richman, Eric E.; Merzouk, Massine B.

    2014-06-12

    A Comparison of 2pi and 4pi Photometric Testing of Directional and Omnidirectional Sources in an Integrating Sphere. These data will help determine if differences in methods should be addresed in test methods specifically for LED products but applicable to other technologies as well

  18. Growth control of epitaxial GeTe-Sb2Te3 films using a line-of-sight quadrupole mass spectrometer

    NASA Astrophysics Data System (ADS)

    Perumal, Karthick; Braun, Wolfgang; Riechert, Henning; Calarco, Raffaella

    2014-06-01

    A narrow growth window combined with highly temperature dependent compositional variations poses a serious problem for the growth of epitaxial GeTe-Sb2Te3 (GST) thin films. The problems are further aggravated by the weak coupling of the radiatively heated non-contact thermocouples to the substrate. An increase in surface temperature during growth as inferred from the increase in desorption of GeTe heteromolecules and the resulting change in alloy composition are studied. Using the desorption signal as a feedback to control the surface temperature, the thermocouple temperature was varied over the duration of the growth to maintain a constant desorption and hence constant surface temperature. Interestingly, the composition of the grown films varies along the GeTe-Sb2Te3 pseudobinary line just by varying the desorption without changing the supplied flux. The out-of-plane lattice constant of the epitaxially grown GST thin film increases with an increase in Ge concentration.

  19. Multilayer scintillation spectrometer for charged pionium detection

    NASA Astrophysics Data System (ADS)

    Krasnov, V. A.; Karnyushina, L. V.; Kuznetsov, S. N.; Kurepin, A. B.; Livanov, A. N.; Pilyar, A. V.

    2013-01-01

    The design description and characteristics of a 14-layer scintillation spectrometer for meson recording are given. The results from testing the spectrometer, calibrating it with cosmic-ray particles, and using the particle beams at energies reaching 1 GeV are presented. The spectrometer design is based on flat scintillation plates glued with wavelength-shifting optic fibers.

  20. Study of Nuclei far From Stability by Using the CHIMERA 4{pi} Detector and Radioactive Beams at LNS

    SciTech Connect

    Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Verde, G.; Amorini, F.; Anzalone, A.; Maiolino, C.; Auditore, L.; Loria, D.; Trifiro, A.; Trimarchi, M.; Cavallaro, S.; Lombardo, I.; Porto, F.; Rizzo, F.; Russotto, P.; Chatterjee, M. B.; Geraci, E.

    2009-08-26

    At LNS are available radioactive beams at tandem and intermediate energies provided respectively by the EXCYT and by the fragmentation FRIBS facilities. Using these beams, and the 4{pi} detector CHIMERA, we want to study excitation and decay of resonances in light exotic nuclei populated with pick-up stripping and other reaction mechanisms. Some preliminary results obtained with stable and unstable beams are reported.

  1. Measurements of π ^{± }, K^{± }, K^0_S, \\varLambda and proton production in proton-carbon interactions at 31 GeV/ c with the NA61/SHINE spectrometer at the CERN SPS

    NASA Astrophysics Data System (ADS)

    Abgrall, N.; Aduszkiewicz, A.; Ali, Y.; Andronov, E.; Antićić, T.; Antoniou, N.; Baatar, B.; Bay, F.; Blondel, A.; Blümer, J.; Bogomilov, M.; Brandin, A.; Bravar, A.; Brzychczyk, J.; Bunyatov, S. A.; Busygina, O.; Christakoglou, P.; Czopowicz, T.; Damyanova, A.; Davis, N.; Debieux, S.; Dembinski, H.; Deveaux, M.; Diakonos, F.; Di Luise, S.; Dominik, W.; Drozhzhova, T.; Dumarchez, J.; Dynowski, K.; Engel, R.; Ereditato, A.; Feofilov, G. A.; Fodor, Z.; Gaździcki, M.; Golubeva, M.; Grebieszkow, K.; Grzeszczuk, A.; Guber, F.; Haesler, A.; Hasegawa, T.; Herve, A.; Hierholzer, M.; Igolkin, S.; Ivashkin, A.; Joković, D.; Johnson, S. R.; Kadija, K.; Kapoyannis, A.; Kaptur, E.; Kiełczewska, D.; Kisiel, J.; Kobayashi, T.; Kolesnikov, V. I.; Kolev, D.; Kondratiev, V. P.; Korzenev, A.; Kowalik, K.; Kowalski, S.; Koziel, M.; Krasnoperov, A.; Kuich, M.; Kurepin, A.; Larsen, D.; László, A.; Lewicki, M.; Lyubushkin, V. V.; Maćkowiak-Pawłowska, M.; Majka, Z.; Maksiak, B.; Malakhov, A. I.; Marchionni, A.; Manić, D.; Marcinek, A.; Marino, A. D.; Marton, K.; Mathes, H.-J.; Matulewicz, T.; Matveev, V.; Melkumov, G. L.; Messerly, B.; Mills, G. B.; Morozov, S.; Mrówczyński, S.; Murphy, S.; Nagai, Y.; Nakadaira, T.; Naskret, M.; Nirkko, M.; Nishikawa, K.; Palczewski, T.; Panagiotou, A. D.; Paolone, V.; Pavin, M.; Petukhov, O.; Pistillo, C.; Płaneta, R.; Popov, B. A.; Posiadała-Zezula, M.; Puławski, S.; Puzović, J.; Rauch, W.; Ravonel, M.; Redij, A.; Renfordt, R.; Richter-Was, E.; Robert, A.; Röhrich, D.; Rondio, E.; Roth, M.; Rubbia, A.; Rumberger, B. T.; Rustamov, A.; Rybczynski, M.; Sadovsky, A.; Sakashita, K.; Sarnecki, R.; Schmidt, K.; Sekiguchi, T.; Selyuzhenkov, I.; Seryakov, A.; Seyboth, P.; Sgalaberna, D.; Shibata, M.; Słodkowski, M.; Staszel, P.; Stefanek, G.; Stepaniak, J.; Ströbele, H.; Šuša, T.; Szuba, M.; Tada, M.; Taranenko, A.; Tefelska, A.; Tefelski, D.; Tereshchenko, V.; Tsenov, R.; Turko, L.; Ulrich, R.; Unger, M.; Vassiliou, M.; Veberič, D.; Vechernin, V. V.; Vesztergombi, G.; Vinogradov, L.; Wilczek, A.; Wlodarczyk, Z.; Wojtaszek-Szwarc, A.; Wyszyński, O.; Yarritu, K.; Zambelli, L.; Zimmerman, E. D.

    2016-02-01

    Measurements of hadron production in p + C interactions at 31 GeV/ c are performed using the NA61/SHINE spectrometer at the CERN SPS. The analysis is based on the full set of data collected in 2009 using a graphite target with a thickness of 4 % of a nuclear interaction length. Inelastic and production cross sections as well as spectra of π ^{± }, K^{± }, p, K^0_S and \\varLambda are measured with high precision. These measurements are essential for improved calculations of the initial neutrino fluxes in the T2K long-baseline neutrino oscillation experiment in Japan. A comparison of the NA61/SHINE measurements with predictions of several hadroproduction models is presented.

  2. Monolithic spectrometer

    DOEpatents

    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

    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.

  3. Monolithic spectrometer

    DOEpatents

    Rajic, Slobodan; Egert, Charles M.; Kahl, William K.; Snyder, Jr., William B.; Evans, III, Boyd M.; Marlar, Troy A.; Cunningham, Joseph P.

    1998-01-01

    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.

  4. Correlation spectrometer

    DOEpatents

    Sinclair, Michael B.; Pfeifer, Kent B.; Flemming, Jeb H.; Jones, Gary D.; Tigges, Chris P.

    2010-04-13

    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.

  5. Exact fan-beam and 4{pi}-acquisition cone-beam SPECT algorithms with uniform attenuation correction

    SciTech Connect

    Tang Qiulin; Zeng, Gengsheng L.; Wu Jiansheng; Gullberg, Grant T.

    2005-11-15

    This paper presents analytical fan-beam and cone-beam reconstruction algorithms that compensate for uniform attenuation in single photon emission computed tomography. First, a fan-beam algorithm is developed by obtaining a relationship between the two-dimensional (2D) Fourier transform of parallel-beam projections and fan-beam projections. Using this relationship, 2D Fourier transforms of equivalent parallel-beam projection data are obtained from the fan-beam projection data. Then a quasioptimal analytical reconstruction algorithm for uniformly attenuated Radon data, developed by Metz and Pan, is used to reconstruct the image. A cone-beam algorithm is developed by extending the fan-beam algorithm to 4{pi} solid angle geometry. The cone-beam algorithm is also an exact algorithm.

  6. Optimized 4 pi spherical shell depleted uranium-water shield weights for 200 to 550-megawatt reactors

    NASA Technical Reports Server (NTRS)

    Wohl, M. L.; Celnik, J.; Schamberger, R. D.

    1972-01-01

    Optimization calculations to determine minimum 4 pi spherical-shell weights were performed at 200-, 375-, and 550-megawatt-thermal reactor power levels. Monte Carlo analyses were performed for a reactor power level corresponding to 375 megawatts. Power densities for the spherical reactor model used varied from 64.2 to 256 watts per cubic centimeter. The dose rate constraint in the optimization calculations was 0.25 mrem per hour at 9.14 meters from the reactor center. The resulting shield weights were correlated with the reactor power levels and power densities by a regression analysis. The optimum shield weight for a 375-megawatt, 160-watt-per-cubic-centimeter reactor was 202,000 kilograms.

  7. Multidimensional spectrometer

    SciTech Connect

    Zanni, Martin Thomas; Damrauer, Niels H.

    2010-07-20

    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.

  8. Astronomical Fourier spectrometer.

    PubMed

    Connes, P; Michel, G

    1975-09-01

    A high resolution near ir Fourier spectrometer with the same general design as previously described laboratory instruments has been built for astronomical observations at a coudé focus. Present spectral range is 0.8-3.5 microm with PbS and Ge detectors and maximum path difference 1 m. The servo system can accommodate various recording modes: stepping or continuous scan, path difference modulation, sky chopping. A real time computer is incorporated into the system, which has been set up at the Hale 500-cm telescope on Mount Palomar. Samples of the results are given. PMID:20154966

  9. Nuclear structure analysis using the Orange Spectrometer

    SciTech Connect

    Regis, J.-M.; Pascovici, Gh.; Christen, S.; Meersschout, T.; Bernards, C.; Fransen, Ch.; Dewald, A.; Braun, N.; Heinze, S.; Thiel, S.; Jolie, J.; Materna, Th.

    2009-01-28

    Recently, an Orange spectrometer, a focusing iron-free magnetic spectrometer, has been installed at a beam line of the 10 MV Tandem accelerator of the IKP of the University of Cologne. The high efficiency of 15% of 4{pi} for the detection of conversion electrons and the energy resolution of 1% makes the Orange spectrometer a powerful instrument. From the conversion electron spectrum, transition multipolarities can be determined using the so called K to L ratio. In combination with an array of germanium and lanthanum bromide detectors, e{sup -}-{gamma}-coincidences can be performed to investigate the level scheme. Moreover, the very fast lanthanum bromide scintillator with an energy resolution of 3% allows e{sup -}-{gamma} lifetime measurements down to 0.3 ns. A second Orange spectrometer can be added to build the Double Orange Spectrometer for e{sup -}-e{sup -}-coincidences. It is indispensable for lifetime measurements of low intensity or nearby lying transitions as often occur in odd-A and odd-odd nuclei. The capabilities are illustrated with several examples.

  10. SCINTILLATION SPECTROMETER

    DOEpatents

    Bell, P.R.; Francis, J.E.

    1960-06-21

    A portable scintillation spectrometer is described which is especially useful in radio-biological studies for determining the uptake and distribution of gamma -emitting substances in tissue. The spectrometer includes a collimator having a plurality of apertures that are hexagonal in cross section. Two crystals are provided: one is activated to respond to incident rays from the collimator; the other is not activated and shields the first from external radiation.

  11. Multiaperture Spectrometer

    NASA Technical Reports Server (NTRS)

    Schindler, Rudolf A.; Pagano, Robert J.; O'Callaghan, Fred G.

    1991-01-01

    Proposed multiaperture spectrometer containing single grating provides high spectral resolution over broad spectrum. Produces parallel line images, each of which highly spectrally resolved display of intensity vs. wavelength in wavelength band of one of orders of spectrum produced by grating. Advantages; convenient two-dimensional spectral image, fewer components, and greater efficiency.

  12. Spectrometer gun

    DOEpatents

    Waechter, David A.; Wolf, Michael A.; Umbarger, C. John

    1985-01-01

    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.

  13. Spectrometer gun

    DOEpatents

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

    1981-11-03

    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.

  14. The Spectrometer

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2012-01-01

    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…

  15. MASS SPECTROMETER

    DOEpatents

    White, F.A.

    1960-08-23

    A mass spectrometer is designed with a first adjustable magnetic field for resolving an ion beam into beams of selected masses, a second adjustable magnetic field for further resolving the ion beam from the first field into beams of selected masses, a thin foil disposed in the path of the beam between the first and second magnets to dissociate molecular ions incident thereon, an electrostatic field for further resolving the ion beam from the second field into beams of selected masses, and a detector disposed adjacent to the electrostatic field to receive the ion beam.

  16. High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station.

    PubMed

    Accardo, L; Aguilar, M; Aisa, D; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Carosi, G; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cerreta, D; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Cindolo, F; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Haas, D; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Henning, R; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Levi, G; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lolli, M; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Massera, F; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Monreal, B; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pauluzzi, M; Pedreschi, E; Pensotti, S; Pereira, R; Pilastrini, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rossi, L; Rozhkov, A; Rozza, D; Rybka, G; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Vitale, V; Volpini, G; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Wu, K Y; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhou, F; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

    2014-09-19

    A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy. PMID:25279616

  17. Spin spectrometer at the holified heavy-ion research facility and some planned experiments

    SciTech Connect

    Sarantites, D. G.; Jaaskelainen, M.; Hood, J. T.; Woodward, R.; Barker, J. H.; Hensley, D. C.; Halbert, M. L.; Chan, Y. D.

    1980-01-01

    The 4..pi.. multidetector ..gamma..-ray spectrometer at the Holified Heavy-ion Research Facility (HHIRF) is described in some detail. The following important features of this spectrometer are discussed: (a) the geometric arrangement, (b) the actual performance of the individual detector elements, (c) the associated electronics and data acquisition system, and (d) the response of the system to input ..gamma..-cascades including the effect of crystal-to-crystal scattering and the response to neutrons. The first few experiments to be performed are briefly described.

  18. The Detector for Advanced Neutron Capture Experiments: A 4{pi} BaF2 Detector for Neutron Capture Measurements at LANSCE

    SciTech Connect

    Ullmann, J.L.; Esch, E.-I.; Haight, R.C.; Hunt, L.; O'Donnell, J.M.; Reifarth, R.; Agvaanluvsan, U.; Alpizar, A.; Hatarik, R.; Bond, E.M.; Bredeweg, T.A.; Kronenberg, A.; Rundberg, R.S.; Vieira, D.J.; Wilhelmy, J.B.; Folden, C.M.; Hoffman, D.C.; Greife, U.; Schwantes, J.M.; Strottman, D.D.

    2005-05-24

    The Detector for Advanced Neutron Capture Experiments (DANCE) is a 162-element 4{pi} BaF2 array designed to make neutron capture cross-section measurements on rare or radioactive targets with masses as little as one milligram. Accurate capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. These cross sections are difficult to calculate accurately and must be measured. The design and initial performance results of DANCE is discussed.

  19. Standardization of 152Eu and 154Eu by 4pibeta-4pigamma coincidence method and 4pi(beta+gamma) integral counting.

    PubMed

    Yamada, Takahiro; Nakamura, Yoshihide; Kawada, Yasushi; Sato, Yasushi; Hino, Yoshio

    2006-01-01

    The 4pibeta-4pigamma coincidence counting and 4pi(beta+gamma) integral counting techniques were applied for the standardization of 152Eu and 154Eu. In these techniques, the beta-detector is composed of two thin plastic scintillators sandwiching the source coupled with a slender photomultiplier tube. This beta-detector was inserted into a large well-type NaI(Tl) scintillation detector for gamma-ray detection, making a 4pibeta-4pigamma detector configuration. The results obtained by the above two techniques were in good agreement and consistent with the results of international comparisons. PMID:16618542

  20. Precision Measurement of the (e^{+}+e^{-}) Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station.

    PubMed

    Aguilar, M; Aisa, D; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Crispoltoni, M; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Donnini, F; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gargiulo, C; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pauluzzi, M; Pedreschi, E; Pensotti, S; Pereira, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Räihä, T; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

    2014-11-28

    We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e^{+}+e^{-}) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale). PMID:25494065

  1. Precision Measurement of the(e++e-)Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station

    DOE PAGESBeta

    Aguilar, M.; Aisa, D.; Alpat, B.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; et al

    2014-11-26

    We present a measurement of the cosmic ray (e++e-) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e++e-) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ= -3.170 ± 0.008(stat+syst) ± 0.008(energy scale).

  2. E1 and E2 S factors of {sup 12}C({alpha},{gamma}{sub 0}){sup 16}O from {gamma}-ray angular distributions with a 4 {pi}-detector array

    SciTech Connect

    Assuncao, M.; Lefebvre-Schuhl, A.; Kiener, J.; Tatischeff, V.; Boukari-Pelissie, C.; Coc, A.; Correia, J.J.; Grama, C.; Hannachi, F.; Korichi, A.; LeDu, D.; Lopez-Martens, A.; Meunier, R.; Thibaud, J.P.; Beck, C.; Courtin, S.

    2006-05-15

    A new experiment to determine the thermonuclear cross section of the {sup 12}C({alpha},{gamma}){sup 16}O reaction has been performed in regular kinematics using an intense {alpha}-particle beam of up to 340 {mu}A from the Stuttgart DYNAMITRON. For the first time, a 4{pi}-germanium-detector setup has been used to measure the angular distribution of the {gamma} rays at all angles simultaneously. It consisted of an array of nine EUROGAM high-purity Ge detectors in close geometry, actively shielded individually with bismuth germanate crystals. The {sup 12}C targets were isotopically enriched by magnetic separation during implantation. The depth profiles of the implanted carbon in the {sup 12}C targets were determined by Rutherford backscattering for purposes of cross-section normalization and absolute determination of the E1 and E2 S factors. Angular distributions of the {gamma} decay to the {sup 16}O ground state were measured in the energy range E{sub c.m.}=1.30-2.78 MeV and in the angular range (lab.) 30 deg. -130 deg. . From these distributions, astrophysical E1 and E2 S-factor functions vs energy were calculated, both of which are indispensable to the modeling of this reaction and the extrapolation toward lower energies. The separation of the E1 and E2 capture channels was done both by taking the phase value {phi}{sub 12} as a free parameter and by fixing it using the results of elastic {alpha}-particle scattering on {sup 12}C in the same energy range.

  3. NEAR Gamma Ray Spectrometer Characterization and Repair

    NASA Technical Reports Server (NTRS)

    Groves, Joel Lee; Vajda, Stefan

    1998-01-01

    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.

  4. The LASS (Larger Aperture Superconducting Solenoid) spectrometer

    SciTech Connect

    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

    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.

  5. Tropospheric Emission Spectrometer and Airborne Emission Spectrometer

    NASA Technical Reports Server (NTRS)

    Glavich, T.; Beer, R.

    1996-01-01

    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.

  6. Compact Infrared Spectrometers

    NASA Technical Reports Server (NTRS)

    Mouroulis, Pantazis

    2009-01-01

    Concentric spectrometer forms are advantageous for constructing a variety of systems spanning the entire visible to infrared range. Spectrometer examples are given, including broadband or high resolution forms. Some issues associated with the Dyson catadioptric type are also discussed.

  7. Miniature Neutron-Alpha Activation Spectrometer

    NASA Astrophysics Data System (ADS)

    Rhodes, Edgar; Holloway, James Paul; He, Zhong; Goldsten, John

    2002-10-01

    We are developing a miniature neutron-alpha activation spectrometer for in-situ analysis of chem-bio samples, including rocks, fines, ices, and drill cores, suitable for a lander or Rover platform for Mars or outer-planet missions. In the neutron-activation mode, penetrating analysis will be performed of the whole sample using a γ spectrometer and in the α-activation mode, the sample surface will be analyzed using Rutherford-backscatter and x-ray spectrometers. Novel in our approach is the development of a switchable radioactive neutron source and a small high-resolution γ detector. The detectors and electronics will benefit from remote unattended operation capabilities resulting from our NEAR XGRS heritage and recent development of a Ge γ detector for MESSENGER. Much of the technology used in this instrument can be adapted to portable or unattended terrestrial applications for detection of explosives, chemical toxins, nuclear weapons, and contraband.

  8. Performance of an INTEGRAL spectrometer model

    NASA Technical Reports Server (NTRS)

    Jean, P.; Naya, J. E.; vonBallmoos, P.; Vedrenne, G.; Teegarden, B.

    1997-01-01

    Model calculations for the INTEGRAL spectrometer (SPI) onboard the future INTErnational Gamma Ray Astrophysics Laboratory (INTEGAL) are presented, where the sensitivity for narrow lines is based on estimates of the background level and the detection efficiency. The instrumental background rates are explained as the sum of various components that depend on the cosmic ray intensity and the spectrometer characteristics, such as the mass distribution around the Ge detectors, the passive material, the characteristics of the detector system and the background reduction techniques. Extended background calculations were performed with Monte Carlo simulations and using semi-empirical and calculated neutron and proton cross sections. In order to improve the INTEGRAL spectrometer sensitivity, several designs and background reduction techniques were compared for an instrument with a fixed detector volume.

  9. A short-orbit spectrometer for Hall C

    SciTech Connect

    Jackson, H.E.; Kowalczyk, R.S.; Potterveld, D.H.; Zeidman, B.; Boudrie, R.L.; Hart, V.E.

    1992-09-01

    A short-orbit spectrometer capable of detecting particles with momentum < 2.0 GeV/c with moderate energy and angular resolution will be available in Hall C for operations in coincidence with the HMS spectrometer or for stand alone operation. The design is based on a QD(-D) configuration which can meet the needs of a broad spectrum of studies appropriate to Hall C. Measurements will be possible for angles of up to 20 degrees out of plane.

  10. A short-orbit spectrometer for Hall C

    SciTech Connect

    Jackson, H.E.; Kowalczyk, R.S.; Potterveld, D.H.; Zeidman, B. ); Boudrie, R.L.; Hart, V.E. )

    1992-01-01

    A short-orbit spectrometer capable of detecting particles with momentum < 2.0 GeV/c with moderate energy and angular resolution will be available in Hall C for operations in coincidence with the HMS spectrometer or for stand alone operation. The design is based on a QD(-D) configuration which can meet the needs of a broad spectrum of studies appropriate to Hall C. Measurements will be possible for angles of up to 20 degrees out of plane.

  11. Superconducting magnets for space flight. [magnetic cosmic ray spectrometers

    NASA Technical Reports Server (NTRS)

    Golden, R. L.

    1975-01-01

    The operating principle and application of superconducting magnetic spectrometers for cosmic ray analysis are described. Magnetic spectrometer experiments are thought to be possible in the areas of charge composition and its possible energy dependence, isotopic separation up to several GeV/n, electrons and positrons energy spectra, galactic secondary antiprotons, searches for primordial antimatter, searches for substructure in energy spectra, and gamma ray astronomy. Operational problems associated with the magnets are discussed, and a possible shuttle payload is also described.

  12. The molecular mechanism of polygalasaponin F-mediated decreases in TNFα: emphasizing the role of the TLR4-PI3K/AKT-NF-κB pathway.

    PubMed

    Yan, Wen-Fen; Shao, Qian-Hang; Zhang, Dong-Ming; Yuan, Yu-He; Chen, Nai-Hong

    2015-01-01

    Polygalasaponin F (PS-F), an oleanane-type triterpenoid saponin extracted from Polygala japonica, decreases the release of the inflammatory cytokine tumor necrosis factor α (TNFα), but the precise molecular mechanisms by which this event occurs are not fully understood. To study the anti-neuroinflammatory mechanisms of PS-F, enzyme-linked immunosorbent assay was used to detect the secretion of TNFα from BV-2 microglial cells. Nuclear proteins extracted from BV-2 microglial cells stimulated by lipopolysaccharide (LPS) and pretreated with/without inhibitors were measured by Western blotting, and cell viability was evaluated by MTT analysis. The results indicated that inhibition of toll-like receptor (TLR) 4 (CLI-095 1 μg/ml), phosphatidylinositol 3-kinase (PI3K) (Ly294002 10 μM) or IκBα phosphorylation (Bay11-7082 10 μM) completely prevents the release of TNFα induced by LPS without affecting cell viability and attenuated the nuclear translocation of p65 stimulated by LPS. In addition, PS-F exhibited a similar trend regarding TNFα release, AKT phosphorylation and NF-κB translocation. These results suggest that PS-F reduces neuroinflammatory cytokine secretion through the regulation of the TLR4-PI3K/AKT-NF-κB signaling pathway. PMID:26235355

  13. Spherical grating spectrometers

    NASA Astrophysics Data System (ADS)

    O'Donoghue, Darragh; Clemens, J. Christopher

    2014-07-01

    We describe designs for spectrometers employing convex dispersers. The Offner spectrometer was the first such instrument; it has almost exclusively been employed on satellite platforms, and has had little impact on ground-based instruments. We have learned how to fabricate curved Volume Phase Holographic (VPH) gratings and, in contrast to the planar gratings of traditional spectrometers, describe how such devices can be used in optical/infrared spectrometers designed specifically for curved diffraction gratings. Volume Phase Holographic gratings are highly efficient compared to conventional surface relief gratings; they have become the disperser of choice in optical / NIR spectrometers. The advantage of spectrometers with curved VPH dispersers is the very small number of optical elements used (the simplest comprising a grating and a spherical mirror), as well as illumination of mirrors off axis, resulting in greater efficiency and reduction in size. We describe a "Half Offner" spectrometer, an even simpler version of the Offner spectrometer. We present an entirely novel design, the Spherical Transmission Grating Spectrometer (STGS), and discuss exemplary applications, including a design for a double-beam spectrometer without any requirement for a dichroic. This paradigm change in spectrometer design offers an alternative to all-refractive astronomical spectrometer designs, using expensive, fragile lens elements fabricated from CaF2 or even more exotic materials. The unobscured mirror layout avoids a major drawback of the previous generation of catadioptric spectrometer designs. We describe laboratory measurements of the efficiency and image quality of a curved VPH grating in a STGS design, demonstrating, simultaneously, efficiency comparable to planar VPH gratings along with good image quality. The stage is now set for construction of a prototype instrument with impressive performance.

  14. Gamma-ray spectrometer utilizing xenon at high pressure

    SciTech Connect

    Smith, G.C.; Mahler, G.J.; Yu, B.; Kane, W.R.; Markey, J.K.

    1994-08-01

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

  15. Differential Moessbauer spectrometer

    SciTech Connect

    Kurinyi, Yu.A.; Grotov, Yu.D.

    1988-07-01

    A spectrometer is described that permits hardware differentiation of spectra with respect to the energy of gamma radiation, specimen temperature, etc. Differentiation is performed by secondary modulation of source motion with subsequent phase-sensitive detection at the harmonics. The spectrometer is CAMAC-compatible and permits simultaneous measurement of the first four harmonics.

  16. The Quadrupole Mass Spectrometer

    ERIC Educational Resources Information Center

    Matheson, E.; Harris, T. J.

    1969-01-01

    Describes the construction and operation of a quadrupole mass spectrometer for experiments in an advanced-teaching laboratory. Discusses the theory of operation of the spectrometer and the factors affecting the resolution. Some examples of mass spectra obtained with this instrument are presented and discussed. (LC)

  17. Comparison of the energy response of an ionization spectrometer for pions and protons

    NASA Technical Reports Server (NTRS)

    Jones, W. V.; Verma, S. D.

    1971-01-01

    An ionization spectrometer consisting of a sandwich of iron absorbers and plastic scintillation counters was used to measure the energy of pions and protons in the interval 10 to 1000 GeV. For the limited energy interval of 10 to 40 GeV, pions and protons were identified by an air cerenkov counter. Interactions in carbon were studied in a multiplate cloud chamber placed between the cerenkov counter and the spectrometer. Knowledge of these interactions were used in conjunction with a Monte Carlo simulation of the cascade process to study differences in the response of the spectrometer to pions and protons.

  18. Measurements on the development of cascades in a tungsten-scintillator ionization spectrometer

    NASA Technical Reports Server (NTRS)

    Cheshire, D. L.; Huggett, R. W.; Johnson, D. P.; Jones, W. V.; Rountree, S. P.; Schmidt, W. K. H.; Kurz, R. J.; Bowen, T.; Delise, D. A.; Krider, E. P.

    1975-01-01

    The response of a tungsten-scintillator ionization spectrometer to accelerated particle beams has been investigated. Results obtained from exposure of the approx. 1000 g/sq cm apparatus to 5, 10, and 15 GeV/c electrons and pions as well as to 2.1 GeV/nucleon C-12 and O-16 ions are presented. These results include cascade-development curves, fractions of the primary energy measured by the spectrometer, and resolutions of the apparatus for measuring the primary energies. For 15 GeV/c electrons, an average of about 82% of the incident energy is measured by the apparatus with resolution (normal standard deviation) of about 6%. For 15 GeV/c pions, an average of about 65% of the incident energy is measured with resolution of about 18%. The energy resolution improves with increasing energy and with increasing depth of the spectrometer.

  19. A Simple Raman Spectrometer.

    ERIC Educational Resources Information Center

    Blond, J. P.; Boggett, D. M.

    1980-01-01

    Discusses some basic physical ideas about light scattering and describes a simple Raman spectrometer, a single prism monochromator and a multiplier detector. This discussion is intended for British undergraduate physics students. (HM)

  20. The imaging spectrometer approach

    NASA Technical Reports Server (NTRS)

    Wellman, J. B.

    1982-01-01

    Two important sensor design drivers are the requirement for spatial registration of the spectral components and the implementation of the advanced multispectral capability, including spectral band width, number of bands and programmability. The dispersive approach, fundamental to the imaging spectrometer concept, achieves these capabilities by utilizing a spectrometer to disperse the spectral content while preserving the spatial identity of the information in the cross-track direction. Area array detectors in the spectrometer focal plane detect and store the spatial and multispectral content for each line of the image. The choice of spectral bands, image IFOV and swath width is implemented by programmed readout of the focal plane. These choices in conjunction with data compression are used to match the output data rate with the telemetry link capability. Progress in the key technologies of optics, focal plane detector arrays, onboard processing, and focal plane cooling supports the viability of the imaging spectrometer approach.

  1. Composite Spectrometer Prisms

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    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.

  2. The SLIM spectrometer.

    PubMed

    Cantrell, Kevin M; Ingle, James D

    2003-01-01

    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

  3. Imaging Fourier transform spectrometer

    SciTech Connect

    Bennett, C.L.

    1993-09-13

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

  4. Fourier Transform Spectrometer System

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F. (Inventor)

    2014-01-01

    A Fourier transform spectrometer (FTS) data acquisition system includes an FTS spectrometer that receives a spectral signal and a laser signal. The system further includes a wideband detector, which is in communication with the FTS spectrometer and receives the spectral signal and laser signal from the FTS spectrometer. The wideband detector produces a composite signal comprising the laser signal and the spectral signal. The system further comprises a converter in communication with the wideband detector to receive and digitize the composite signal. The system further includes a signal processing unit that receives the composite signal from the converter. The signal processing unit further filters the laser signal and the spectral signal from the composite signal and demodulates the laser signal, to produce velocity corrected spectral data.

  5. Microbolometer imaging spectrometer.

    PubMed

    Johnson, William R; Hook, Simon J; Shoen, Steven M

    2012-03-01

    Newly developed, high-performance, long-wave- and mid-wave-IR Dyson spectrometers offer a compact, low-distortion, broadband, imaging spectrometer design. The design is further accentuated when coupled to microbolometer array technology. This novel coupling allows radiometric and spectral measurements of high-temperature targets. It also serves to be unique since it allows for the system to be aligned warm. This eliminates the need for cryogenic temperature cycling. Proof of concept results are shown for a spectrometer with a 7.5 to 12.0 μm spectral range and approximately 20 nm per spectral band (~200 bands). Results presented in this Letter show performance for remote hot targets (>200 °C) using an engineering grade spectrometer and IR commercial lens assembly. PMID:22378399

  6. Pseudomorphic GeSn/Ge (001) heterostructures

    SciTech Connect

    Tonkikh, A. A.; Talalaev, V. G.; Werner, P.

    2013-11-15

    The synthesis of pseudomorphic GeSn heterostructures on a Ge (001) substrate by molecular-beam epitaxy is described. Investigations by transmission electron microscopy show that the GeSn layers are defect free and possess cubic diamondlike structure. Photoluminescence spectroscopy reveals interband radiative recombination in the GeSn quantum wells, which is identified as indirect transitions between the subbands of heavy electrons and heavy holes. On the basis of experimental data and modeling of the band structure of pseudomorphic GeSn compounds, the lower boundary of the bowing parameter for the indirect band gap is estimated as b{sub L} {>=} 1.47 eV.

  7. Particle identification algorithms for the HARP forward spectrometer

    NASA Astrophysics Data System (ADS)

    Catanesi, M. G.; Radicioni, E.; Edgecock, R.; Ellis, M.; Robbins, S.; Soler, F. J. P.; Gößling, C.; Bunyatov, S.; Chelkov, G.; Chukanov, A.; Dedovitch, D.; Gostkin, M.; Guskov, A.; Khartchenko, D.; Klimov, O.; Krasnoperov, A.; Kroumchtein, Z.; Kustov, D.; Nefedov, Y.; Popov, B.; Serdiouk, V.; Tereshchenko, V.; Zhemchugov, A.; Di Capua, E.; Vidal-Sitjes, G.; Artamonov, A.; Arce, P.; Giani, S.; Gilardoni, S.; Gorbunov, P.; Grant, A.; Grossheim, A.; Gruber, P.; Ivanchenko, V.; Kayis-Topaksu, A.; Panman, J.; Papadopoulos, I.; Pasternak, J.; Tcherniaev, E.; Tsukerman, I.; Veenhof, R.; Wiebusch, C.; Zucchelli, P.; Blondel, A.; Borghi, S.; Campanelli, M.; Cervera-Villanueva, A.; Morone, M. C.; Prior, G.; Schroeter, R.; Kato, I.; Nakaya, T.; Nishikawa, K.; Ueda, S.; Gastaldi, U.; Mills, G. B.; Graulich, J. S.; Grégoire, G.; Bonesini, M.; De Min, A.; Ferri, F.; Paganoni, M.; Paleari, F.; Kirsanov, M.; Bagulya, A.; Grichine, V.; Polukhina, N.; Palladino, V.; Coney, L.; Schmitz, D.; Barr, G.; De Santo, A.; Pattison, C.; Zuber, K.; Bobisut, F.; Gibin, D.; Guglielmi, A.; Laveder, M.; Menegolli, A.; Mezzetto, M.; Dumarchez, J.; Vannucci, F.; Ammosov, V.; Koreshev, V.; Semak, A.; Zaets, V.; Dore, U.; Orestano, D.; Pastore, F.; Tonazzo, A.; Tortora, L.; Booth, C.; Buttar, C.; Hodgson, P.; Howlett, L.; Bogomilov, M.; Chizhov, M.; Kolev, D.; Tsenov, R.; Piperov, S.; Temnikov, P.; Apollonio, M.; Chimenti, P.; Giannini, G.; Santin, G.; Hayato, Y.; Ichikawa, A.; Kobayashi, T.; Burguet-Castell, J.; Gómez-Cadenas, J. J.; Novella, P.; Sorel, M.; Tornero, A.

    2007-03-01

    The particle identification (PID) methods used for the calculation of secondary pion yields with the HARP forward spectrometer are presented. Information from time of flight and Cherenkov detectors is combined using likelihood techniques. The efficiencies and purities associated with the different PID selection criteria are obtained from the data. For the proton-aluminium interactions at 12.9 GeV/ c incident momentum, the PID efficiencies for positive pions are 86% in the momentum range below 2 GeV/ c, 92% between 2 and 3 GeV/ c and 98% in the momentum range above 3 GeV/ c. The purity of the selection is better than 92% for all momenta. Special emphasis has been put on understanding the main error sources. The final PID uncertainty on the pion yield is 3.3%.

  8. Large Isotope Spectrometer for Astromag

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Klarmann, J.; Israel, M. H.; Garrard, T. L.; Mewaldt, R. A.; Stone, E. C.; Ormes, J. F.; Streitmatter, R. E.; Rasmussen, I. L.; Wiedenbeck, M. E.

    1990-01-01

    The Large Isotope Spectrometer for Astromag (LISA) is an experiment designed to measure the isotopic composition and energy spectra of cosmic rays for elements extending from beryllium through zinc. The overall objectives of this investigation are to study the origin and evolution of galactic matter; the acceleration, transport, and time scales of cosmic rays in the galaxy; and search for heavy antinuclei in the cosmic radiation. To achieve these objectives, the LISA experiment will make the first identifications of individual heavy cosmic ray isotopes in the energy range from about 2.5 to 4 GeV/n where relativistic time dilation effects enhance the abundances of radioactive clocks and where the effects of solar modulation and cross-section variations are minimized. It will extend high resolution measurements of individual element abundances and their energy spectra to energies of nearly 1 TeV/n, and has the potential for discovering heavy anti-nuclei which could not have been formed except in extragalactic sources.

  9. Electron-proton spectrometer

    NASA Technical Reports Server (NTRS)

    Winckler, J. R.

    1973-01-01

    An electron-proton spectrometer was designed to measure the geomagnetically trapped radiation in a geostationary orbit at 6.6 earth radii in the outer radiation belt. This instrument is to be flown on the Applications Technology Satellite-F (ATS-F). The electron-proton spectrometer consists of two permanent magnet surface barrier detector arrays and associated electronics capable of selecting and detecting electrons in three energy ranges: (1) 30-50 keV, (2) 150-200 keV, and (3) 500 keV and protons in three energy ranges. The electron-proton spectrometer has the capability of measuring the fluxes of electrons and protons in various directions with respect to the magnetic field lines running through the satellite. One magnet detector array system is implemented to scan between EME north and south through west, sampling the directional flux in 15 steps. The other magnet-detector array system is fixed looking toward EME east.

  10. Compact Grism Spectrometer

    NASA Astrophysics Data System (ADS)

    Teare, S. W.

    2003-05-01

    Many observatories and instrument builders are retrofitting visible and near-infrared spectrometers into their existing imaging cameras. Camera designs that reimage the focal plane and have the optical filters located in a pseudo collimated beam are ideal candidates for the addition of a spectrometer. One device commonly used as the dispersing element for such spectrometers is a grism. The traditional grism is constructed from a prism that has had a diffraction grating applied on one surface. The objective of such a design is to use the prism wedge angle to select the desired "in-line" or "zero-deviation" wavelength that passes through on axis. The grating on the surface of the prism provides much of the dispersion for the spectrometer. A grism can also be used in a "constant-dispersion" design which provides an almost linear spatial scale across the spectrum. In this paper we provide an overview of the development of a grism spectrometer for use in a near infrared camera and demonstrate that a compact grism spectrometer can be developed on a very modest budget that can be afforded at almost any facility. The grism design was prototyped using visible light and then a final device was constructed which provides partial coverage in the near infrared I, J, H and K astronomical bands using the appropriate band pass filter for order sorting. The near infrared grism presented here provides a spectral resolution of about 650 and velocity resolution of about 450 km/s. The design of this grism relied on a computer code called Xspect, developed by the author, to determine the various critical parameters of the grism. This work was supported by a small equipment grant from NASA and administered by the AAS.

  11. Broad band waveguide spectrometer

    DOEpatents

    Goldman, Don S.

    1995-01-01

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

  12. The Apollo Alpha Spectrometer.

    NASA Technical Reports Server (NTRS)

    Jagoda, N.; Kubierschky, K.; Frank, R.; Carroll, J.

    1973-01-01

    Located in the Science Instrument Module of Apollo 15 and 16, the Alpha Particle Spectrometer was designed to detect and measure the energy of alpha particles emitted by the radon isotopes and their daughter products. The spectrometer sensor consisted of an array of totally depleted silicon surface barrier detectors. Biased amplifier and linear gate techniques were utilized to reduce resolution degradation, thereby permitting the use of a single 512 channel PHA. Sensor identification and in-flight radioactive calibration were incorporated to enhance data reduction.

  13. Comparison of imaging spectrometers

    SciTech Connect

    Bennett, C

    2000-01-09

    Realistic signal to noise performance estimates for the various types of instruments being considered for NGST are compared, based on the point source detection values quoted in the available ISIM final reports. The corresponding sensitivity of the various types of spectrometers operating in a full field imaging mode, for both emission line objects and broad spectral distribution objects, is computed and displayed. For the purpose of seeing the earliest galaxies, or the faintest possible emission line sources, the imaging Fourier transform spectrometer emerges superior to all others, by orders of magnitude in speed.

  14. Cooled grating infrared spectrometer for astronomical observations

    NASA Astrophysics Data System (ADS)

    Houck, J. R.; Gull, G. E.

    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.

  15. The HERSCHEL/PACS Spectrometer Pipeline

    NASA Astrophysics Data System (ADS)

    Schreiber, J.; Wieprecht, E.; de Jong, J.; Wetzstein, M.; Jacobson, J.; Huygen, R.; Appleton, P.; Bouwman, J.; Contursi, A.; Fadda, D.; Jean, C.; Klaas, U.; Royer, P.; Vandenbussche, B.

    2009-09-01

    ESA's Herschel Space Observatory, to be launched in 2009, is the first space observatory covering the full far-infrared and sub-millimeter wavelength range (60 - 670 micron). The Photodetector Array Camera & Spectrometer (PACS) is one of the three science instruments. It employs two Ge:Ga photoconductor arrays and two bolometer arrays to perform integral field spectroscopy and imaging photometry in the 60 - 210 micron wavelength band. The interactive PACS Spectrometer and Photometer \\citep{wieprecht09} Data Reduction Pipeline is integrated in the Herschel Data Processing System. The DP is implemented using Java technology and written in a common effort by the HERSCHEL Science Center (HSC) and the three instrument teams. We overview the concept and status of the PACS Spectrometer Data Reduction Pipeline. Additionally, we address the instrument mode-dependent data processing and the definition of the products of the different processing levels. Finally, we show first results by applying the pipeline on flight model instrument level test data.

  16. Short-orbit spectrometer for Hall C at CEBAF

    SciTech Connect

    Jackson, H.E.; Potterveld, D.H.; Zeidman, B.

    1995-08-01

    An examination of the proposed experimental program for Hall C at CEBAF reveals a major emphasis on coincidence experiments involving a {open_quotes}core{close_quotes} spectrometer and a second arm capable of detecting particles with momenta < 2 GeV/c with moderate energy and angular resolution. In most cases, the core spectrometer serves to tag a virtual photon, which induces a reaction in a nuclear target resulting in the ejection of a hadron in the energy range (0.2-2.0 GeV) which is observed in the second spectrometer. Nuclear physics topics addressed in these experiments include color transparency, nucleon propagation, pion electroproduction, and hyperon physics. All of these programs require an acceptance in the hadron spectrometer as large as possible in solid angle and momentum to maximize operational efficiency. In addition, relatively short spectrometer drift lengths are required in experiments involving detection of pions or kaons in order to minimize decay losses. Because the requirements for energy resolution in this class of experiments is moderate, typically {approximately} 10{sup -3}, an optimized design with a short optical length less than 10 m will provide a well-matched spectrometer capability. Excellent particle discrimination will be essential for detection of pions and kaons in the presence of high backgrounds. Operation at luminosities as high as 10{sup 38}/cm{sup 2} sec will be required frequently. To provide this second-arm capability, the Argonne group has built, under contract to CEBAF, a short-orbit spectrometer, the SOS, based on a QD{bar D} design. The QD{bar D} configuration provides a large momentum acceptance, with good energy resolution and solid-angle acceptance in a very compact geometry which can meet the needs of a broad spectrum of studies appropriate for Hall C at CEBAF.

  17. Fourier Transform Spectrometer

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Understanding the global atmospheric changes is difficult with today's current technology. However, with high resolution and nearly continuous observations from a satellite, it's possible to transform our understanding of the atmosphere. To enable the next generation of atmospheric science, a new class of orbiting atmospheric sensors is being developed. The foundation of this advanced concept is the Fourier Transform Spectrometer, or FTS.

  18. Cyclotrons as mass spectrometers

    SciTech Connect

    Clark, D.J.

    1984-04-01

    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.

  19. Mass Spectrometers in Space!

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, William B.

    2012-01-01

    Exploration of our solar system over several decades has benefitted greatly from the sensitive chemical analyses offered by spaceflight mass spectrometers. When dealing with an unknown environment, the broadband detection capabilities of mass analyzers have proven extremely valuable in determining the composition and thereby the basic nature of space environments, including the outer reaches of Earth s atmosphere, interplanetary space, the Moon, and the planets and their satellites. Numerous mass analyzer types, including quadrupole, monopole, sector, ion trap, and time-of-flight have been incorporated in flight instruments and delivered robotically to a variety of planetary environments. All such instruments went through a rigorous process of application-specific development, often including significant miniaturization, testing, and qualification for the space environment. Upcoming missions to Mars and opportunities for missions to Venus, Europa, Saturn, Titan, asteroids, and comets provide new challenges for flight mass spectrometers that push to state of the art in fundamental analytical technique. The Sample Analysis at Mars (SAM) investigation on the recently-launch Mars Science Laboratory (MSL) rover mission incorporates a quadrupole analyzer to support direct evolved gas as well as gas chromatograph-based analysis of martian rocks and atmosphere, seeking signs of a past or present habitable environment. A next-generation linear ion trap mass spectrometer, using both electron impact and laser ionization, is being incorporated into the Mars Organic Molecule Analyzer (MOMA) instrument, which will be flown to Mars in 2018. These and other mass spectrometers and mission concepts at various stages of development will be described.

  20. Crystals for stellar spectrometers

    NASA Technical Reports Server (NTRS)

    Alexandropoulos, N. G.; Cohen, G. G.

    1974-01-01

    Crystal evaluation as it applies to instrumentation employed in X-ray astronomy is reviewed, and some solutions are offered to problems that are commonly encountered. A general approach for selecting the most appropriate crystals for a given problem is also suggested. The energy dependence of the diffraction properties of (002) PET, (111) Ge, (101) ADP, (101) KAP, and (001) RAP are reported.

  1. Instrumental background in balloon-borne gamma-ray spectrometers and techniques for its reduction

    NASA Technical Reports Server (NTRS)

    Gehrels, N.

    1985-01-01

    Instrumental background in balloon-borne gamma-ray spectrometers is presented. The calculations are based on newly available interaction cross sections and new analytic techniques, and are the most detailed and accurate published to date. Results compare well with measurements made in the 20 keV to 10 MeV energy range by the Goddard Low Energy Gamma-ray Spectrometer (LEGS). The principal components of the continuum background in spectrometers with GE detectors and thick active shields are: (1) elastic neutron scattering of atmospheric neutrons on the Ge nuclei; (2) aperture flux of atmospheric and cosmic gamma rays; (3) beta decays of unstable nuclides produced by nuclear interactions of atmospheric protons and neutrons with Ge nuclei; and (4) shield leakage of atmospheric gamma rays. The improved understanding of these components leads to several recommended techniques for reducing the background.

  2. Off-axis measurements of atmospheric trace gases by use of an airborne ultraviolet-visible spectrometer.

    PubMed

    Petritoli, Andrea; Ravegnani, Fabrizio; Giovanelli, Giorgio; Bortoli, Daniele; Bonafè, Ubaldo; Kostadinov, Ivan; Oulanovsky, Alexey

    2002-09-20

    An airborne UV-visible spectrometer, the Gas Analyzer Spectrometer Correlating Optical Differences, airborne version (GASCOD/A4pi) was successfully operated during the Airborne Polar Experiment, Geophysica Aircraft in Antarctica airborne campaign from Ushuaia (54 degrees 49' S, 68 degrees 18' W), Argentina in southern spring 1999. The instrument measured scattered solar radiation through three optical windows with a narrow field of view (FOV), one from the zenith, two from the horizontal, as well as actinic fluxes through 2pi FOV radiometric heads. Only a few airborne measurements of scattered solar radiation at different angles from the zenith are available in the literature. With our configuration we attempted to obtain the average line-of-sight concentrations of detectable trace gases. The retrieval method, based on differential optical absorption spectroscopy, is described and results for ozone are shown and compared with measurements from an in situ instrument as the first method of validation. PMID:12269557

  3. Smartphone spectrometer for colorimetric biosensing.

    PubMed

    Wang, Yi; Liu, Xiaohu; Chen, Peng; Tran, Nhung Thi; Zhang, Jinling; Chia, Wei Sheng; Boujday, Souhir; Liedberg, Bo

    2016-05-23

    We report on a smartphone spectrometer for colorimetric biosensing applications. The spectrometer relies on a sample cell with an integrated grating substrate, and the smartphone's built-in light-emitting diode flash and camera. The feasibility of the smartphone spectrometer is demonstrated for detection of glucose and human cardiac troponin I, the latter in conjunction with peptide-functionalized gold nanoparticles. PMID:27163736

  4. Tropospheric and Airborne Emission Spectrometers

    NASA Technical Reports Server (NTRS)

    Glavich, Thomas; Beer, Reinhard

    1996-01-01

    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.

  5. The BaF sub 2 photon spectrometer TAPS

    SciTech Connect

    Novotny, R. . II Physics Inst.)

    1991-04-01

    The detector system TAPS (Two/Three Atm Photon Spectrometer) has been designed and installed to study high energy photons as well neutral mesons produced in relativistic heavy ion reactions. The spectrometer will consist of up to 384 individual BaF{sub 2}-modules packed in arrays of 64 scintillators. Each spectrometer arm, which carries two detector blocks, can be moved around the target location independently. This paper presents the design concept, the specifications of the individual scintillator and test results of sub-arrays performed with monochromatic photons and charged particles. first experiments at GANIL and SIS have been performed exploiting heavy ion beams up to a projectile energy of 1GeV/u.

  6. Surface Plasmon Based Spectrometer

    NASA Astrophysics Data System (ADS)

    Wig, Andrew; Passian, Ali; Boudreaux, Philip; Ferrell, Tom

    2008-03-01

    A spectrometer that uses surface plasmon excitation in thin metal films to separate light into its component wavelengths is described. The use of surface plasmons as a dispersive medium sets this spectrometer apart from prism, grating, and interference based variants and allows for the miniaturization of this device. Theoretical and experimental results are presented for two different operation models. In the first case surface plasmon tunneling in the near field is used to provide transmission spectra of different broad band-pass, glass filters across the visible wavelength range with high stray-light rejection at low resolution as well as absorption spectra of chlorophyll extracted from a spinach leaf. The second model looks at the far field components of surface plasmon scattering.

  7. FAST NEUTRON SPECTROMETER

    DOEpatents

    Davis, F.J.; Hurst, G.S.; Reinhardt, P.W.

    1959-08-18

    An improved proton recoil spectrometer for determining the energy spectrum of a fast neutron beam is described. Instead of discriminating against and thereby"throwing away" the many recoil protons other than those traveling parallel to the neutron beam axis as do conventional spectrometers, this device utilizes protons scattered over a very wide solid angle. An ovoidal gas-filled recoil chamber is coated on the inside with a scintillator. The ovoidal shape of the sensitive portion of the wall defining the chamber conforms to the envelope of the range of the proton recoils from the radiator disposed within the chamber. A photomultiplier monitors the output of the scintillator, and a counter counts the pulses caused by protons of energy just sufficient to reach the scintillator.

  8. Imaging Fourier Transform Spectrometer

    SciTech Connect

    Bennett, C.L.; Carter, M.R.; Fields, D.J.; Hernandez, J.

    1993-04-14

    The operating principles of an Imaging Fourier Transform Spectrometer (IFTS) are discussed. The advantages and disadvantages of such instruments with respect to alternative imaging spectrometers are discussed. The primary advantages of the IFTS are the capacity to acquire more than an order of magnitude more spectral channels than alternative systems with more than an order of magnitude greater etendue than for alternative systems. The primary disadvantage of IFTS, or FTS in general, is the sensitivity to temporal fluctuations, either random or periodic. Data from the IRIFTS (ir IFTS) prototype instrument, sensitive in the infrared, are presented having a spectral sensitivity of 0.01 absorbance units, a spectral resolution of 6 cm{sup {minus}1} over the range 0 to 7899 cm{sup {minus}1}, and a spatial resolution of 2.5 mr.

  9. Ion mass spectrometer

    NASA Technical Reports Server (NTRS)

    Neugebauer, M. (Inventor); Clay, D. R.; Goldstein, B. E.; Goldstein, R.

    1984-01-01

    An ion mass spectrometer is described which detects and indicates the characteristics of ions received over a wide angle, and which indicates the mass to charge ratio, the energy, and the direction of each detected ion. The spectrometer includes a magnetic analyzer having a sector magnet that passes ions received over a wide angle, and an electrostatic analyzer positioned to receive ions passing through the magnetic analyzer. The electrostatic analyzer includes a two dimensional ion sensor at one wall of the analyzer chamber, that senses not only the lengthwise position of the detected ion to indicate its mass to charge ratio, but also detects the ion position along the width of the chamber to indicate the direction in which the ion was traveling.

  10. The Composite Infrared Spectrometer

    NASA Technical Reports Server (NTRS)

    Calcutt, Simon; Taylor, Fredric; Ade, Peter; Kunde, Virgil; Jennings, Donald

    1992-01-01

    The Composite Infrared Spectrometer (CIRS) is a remote sensing instrument to be flown on the Cassini orbiter. It contains two Fourier transform spectrometers covering wavelengths of 7-1000 microns. The instrument is expected to have higher spectral resolution, smaller field of view, and better signal-to-noise performance than its counterpart, IRIS, on the Voyager missions. These improvements allow the study of the variability of the composition and temperature of the atmospheres of both Saturn and Titan with latitude, longitude and height, as well as allowing the possibility of discovery of previously undetected chemical species in these atmospheres. The long wavelengths accessible to CIRS allow sounding deeper into both atmospheres than was possible with IRIS.

  11. The Cryogenic Grating Spectrometer

    NASA Technical Reports Server (NTRS)

    Erickson, Edwin F.; Haas, Michael R.; Colgan, Sean W. J.; Simpson, Janet P.; Rubin, Robert H.

    1995-01-01

    The Cryogenic Grating Spectrometer (CGS) first flew on the KAO in 1982 December and has been open to guest investigators since 1984 October. In the past 12 years it has completed over 100 research flights supporting 13 different principal investigators studying a variety of objects. We briefly describe the instrument, its capabilities and accomplishments, and acknowledge the people who have contributed to its development and operation.

  12. Miniaturized Ion Mobility Spectrometer

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

    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.

  13. Spherical electrostatic electron spectrometer

    NASA Astrophysics Data System (ADS)

    Yang, T.-S.; Kolk, B.; Kachnowski, T.; Trooster, J.; Benczer-Koller, N.

    1982-06-01

    A high transmission, low energy spherical electrostatic electron spectrometer particularly suited to the geometry required for Mössbauer-conversion electron spectroscopy was built. A transmission of 13% at an energy resolution of 2% was obtained with an 0.5 cm diameter source of 13.6 keV electrons. Applications to the study of hyperfine interactions of surfaces and interfaces are discussed.

  14. X-ray Spectrometer

    NASA Technical Reports Server (NTRS)

    Porter, F. Scott

    2004-01-01

    The X-ray Spectrometer (XRS) instrument is a revolutionary non-dispersive spectrometer that will form the basis for the Astro-E2 observatory to be launched in 2005. We have recently installed a flight spare X R S microcalorimeter spectrometer at the EBIT-I facility at LLNL replacing the XRS from the earlier Astro-E mission and providing twice the resolution. The X R S microcalorimeter is an x-ray detector that senses the heat deposited by the incident photon. It achieves a high energy resolution by operating at 0.06K and by carefully controlling the heat capacity and thermal conductance. The XRS/EBIT instrument has 32 pixels in a square geometry and achieves an energy resolution of 6 eV at 6 keV, with a bandpass from 0.1 to 12 keV (or more at higher operating temperature). The instrument allows detailed studies of the x-ray line emission of laboratory plasmas. The XRS/EBIT also provides an extensive calibration "library" for the Astro-E2 observatory.

  15. Recent study for multibaryon states with strangeness in pC interaction at 10 GeV/c

    SciTech Connect

    Aslanyan, P. Zh.

    2013-08-15

    Strange multibaryon states with {Lambda}-hyperon and K{sub s}{sup 0} -meson subsystems has been studied from 700 000 stereo photographs or 10{sup 6} inelastic interactions which was obtained from expose of 2-m propane bubble chamber (PBC) LHEP, JINR to proton beams at 10 GeV/c. The obtained results from PBC can be divided into three subjects: in-medium effects of hadronic particles; baryon spectroscopy; hyper-nucleus production. At present the experimental situation is confused; so is theory. New accelerator research complexes has unique possibility for high-statistic and 4{pi}-geometry study of exotic states.

  16. Mass spectrometers: instrumentation

    NASA Astrophysics Data System (ADS)

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

    1992-09-01

    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

  17. Mossbauer spectrometer radiation detector

    NASA Technical Reports Server (NTRS)

    Singh, J. J. (Inventor)

    1973-01-01

    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.

  18. Neutron range spectrometer

    DOEpatents

    Manglos, S.H.

    1988-03-10

    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.

  19. Automated transportable mass spectrometer

    NASA Astrophysics Data System (ADS)

    Echo, M. W.

    1981-09-01

    The need was identified for a mass spectrometer (MS) which can be conveniently transported among several facilities for rapid verification of the isotopic composition of special nuclear material. This requirement for a light weight, transportable MS for U and Pu mass analysis was met by deleting the gas chromograph (GC) portions of a Hewlett-Packard Model 5992 Quadrupole GCMS and substituting a vacuum lock sample entry system. A programmable power supply and vacuum gauge were added and circuitry modifications were made to enable use of the supplied software.

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

    SciTech Connect

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

    1996-10-01

    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.

  1. Analytical response function for planar Ge detectors

    NASA Astrophysics Data System (ADS)

    García-Alvarez, Juan A.; Maidana, Nora L.; Vanin, Vito R.; Fernández-Varea, José M.

    2016-04-01

    We model the response function (RF) of planar HPGe x-ray spectrometers for photon energies between around 10 keV and 100 keV. The RF is based on the proposal of Seltzer [1981. Nucl. Instrum. Methods 188, 133-151] and takes into account the full-energy absorption in the Ge active volume, the escape of Ge Kα and Kβ x-rays and the escape of photons after one Compton interaction. The relativistic impulse approximation is employed instead of the Klein-Nishina formula to describe incoherent photon scattering in the Ge crystal. We also incorporate a simple model for the continuous component of the spectrum produced by the escape of photo-electrons from the active volume. In our calculations we include external interaction contributions to the RF: (i) the incoherent scattering effects caused by the detector's Be window and (ii) the spectrum produced by photo-electrons emitted in the Ge dead layer that reach the active volume. The analytical RF model is compared with pulse-height spectra simulated using the PENELOPE Monte Carlo code.

  2. The Athena Raman Spectrometer

    NASA Technical Reports Server (NTRS)

    Wang, Alian; Haskin, Larry A.; Jolliff, Bradley; Wdowiak, Tom; Agresti, David; Lane, Arthur L.

    2000-01-01

    Raman spectroscopy provides a powerful tool for in situ mineralogy, petrology, and detection of water and carbon. The Athena Raman spectrometer is a microbeam instrument intended for close-up analyses of targets (rock or soils) selected by the Athena Pancam and Mini-TES. It will take 100 Raman spectra along a linear traverse of approximately one centimeter (point-counting procedure) in one to four hours during the Mars' night. From these spectra, the following information about the target will extracted: (1) the identities of major, minor, and trace mineral phases, organic species (e.g., PAH or kerogen-like polymers), reduced inorganic carbon, and water-bearing phases; (2) chemical features (e.g. Mg/Fe ratio) of major minerals; and (3) rock textural features (e.g., mineral clusters, amygdular filling and veins). Part of the Athena payload, the miniaturized Raman spectrometer has been under development in a highly interactive collaboration of a science team at Washington University and the University of Alabama at Birmingham, and an engineering team at the Jet Propulsion Laboratory. The development has completed the brassboard stage and has produced the design for the engineering model.

  3. Resonant ultrasound spectrometer

    DOEpatents

    Migliori, Albert; Visscher, William M.; Fisk, Zachary

    1990-01-01

    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.

  4. Improved multisphere spectrometer system

    SciTech Connect

    Shonka, J.J.; Schwahn, S.O.; Rogers, P.E.; Misko, C.J.

    1991-01-01

    Shonka Research Associated undertook a research program to improve the capabilities and ease of use of the Bonner sphere spectrometer system. Two key elements formed the heart of this research: replacement of the lithium iodide (LiI(Eu)) detector normally used in the spectrometer system with a spherical boron triflouride (BF{sub 3}) proportional counter and exploitation of an optimized set of nested polyethylene spheres, including boron-loaded spherical shells. Use of a spherical BF{sub 3} detector offers many advantages over the LiI(Eu) crystal. The BF{sub 3} detectors are insensitive to gamma radiation. Lack of gamma sensitivity permits acquiring data with simple electronics and allows determination of neutron spectra and dose in lower neutron-to-gamma ratio fields, including background terrestrial radiation fields. The importance of the lack of gamma sensitivity is underscored by the pending changes in neutron quality factors. The nearly perfect spherical symmetry offers advantages for BF{sub 3} over LiI(Eu) detectors as well. A light pipe, which perturbs measurements, is not needed. The bare BF{sub 3} detector response is not affected by the moderation of neutrons as is the case of the organic light pipe used with LiI(Eu). The spherical symmetry permits the use of smaller diameter shells, which add to the number of response functions.

  5. Spectrometers beyond the laboratory

    SciTech Connect

    Wadsworth, W.

    1996-11-01

    Two new types of miniature Fourier Transform Spectrometers (FTS) presently being built have enabled this technology to be taken out of the laboratory and into the field. Both designs are very rugged, use little power to run, and can be made extremely small and lightweight. They are excellent candidates for airborne use, both in aircraft and satellite applications. One, the Mcro FT, is a mass balanced linear reciprocating scan operating in the 1-2 scan per second speed range. The other, the Turbo FT, uses a rotary scan, enabling it to run at much higher speeds, from 10 to 1000 scans per second. Either type can be built in the visible, near K and thermal IR wavelength ranges, and provide spectral resolution of 1-2 wave-numbers. Results obtained in all these wavelength ranges are presented here. The rotary configuration is more suited to airborne and satellite survey type deployments, due mostly to its rapid scan rate. Either of these sensors will fit into a small, commercially available stabilized pod which can easily be attached to a helicopter or light plane. This results in a very economical flight spectrometer system. 11 figs.

  6. Prototype Neutron Energy Spectrometer

    SciTech Connect

    Stephen Mitchell, Sanjoy Mukhopadhyay, Richard Maurer, Ronald Wolff

    2010-06-16

    The project goals are: (1) Use three to five pressurized helium tubes with varying polyethylene moderators to build a neutron energy spectrometer that is most sensitive to the incident neutron energy of interest. Neutron energies that are of particular interest are those from the fission neutrons (typically around 1-2 MeV); (2) Neutron Source Identification - Use the neutron energy 'selectivity' property as a tool to discriminate against other competing processes by which neutrons are generated (viz. Cosmic ray induced neutron production [ship effect], [a, n] reactions); (3) Determine the efficiency as a function of neutron energy (response function) of each of the detectors, and thereby obtain the composite neutron energy spectrum from the detector count rates; and (4) Far-field data characterization and effectively discerning shielded fission source. Summary of the presentation is: (1) A light weight simple form factor compact neutron energy spectrometer ready to be used in maritime missions has been built; (2) Under laboratory conditions, individual Single Neutron Source Identification is possible within 30 minutes. (3) Sources belonging to the same type of origin viz., (a, n), fission, cosmic cluster in the same place in the 2-D plot shown; and (4) Isotopes belonging to the same source origin like Cm-Be, Am-Be (a, n) or Pu-239, U-235 (fission) do have some overlap in the 2-D plot.

  7. Galactic antiprotons of 0.2-2 GeV energy

    NASA Technical Reports Server (NTRS)

    Shulakova, M. S.; Bogomolov, E. A.; Vasilyev, G. I.; Iodko, M. G.; Krutkov, S. Y.; Lubyanaya, N. D.; Romanov, V. A.; Stepanov, S. V.

    1985-01-01

    Balloon measurements of the galactic antiproton flux in the energy range 0.2 GeV to 2 GeV are presented. The experiments were carried out in the summer of 1984 with magnet spectrometers flown at a residual pressure of approximately 10 g sq cm and cut off rigidity of approximately 0.6 GV. An upper limit for the antiproton to proton flux ratio has been obtained of antiproton/proton (0.2 GeV to 2 GeV) less than 5 x .0001.

  8. Miniaturized MOEMS spectrometer for NIR applications

    NASA Astrophysics Data System (ADS)

    Grueger, Heinrich; Heberer, Andreas; Zimmer, Fabian; Wolter, Alexander; Schenk, Harald

    2005-08-01

    Optical spectroscopy is a common tool for many applications. Micro systems most often use fixed gratings and array detectors. In the infrared wavelength range above the limit for Si-detectors (1100nm) and Ge-detectors (1700nm) respectively, this is either very expensive or almost impossible. Micro opto electro mechanical systems (MOEMS) offer very promising options. A movable grating can be realized by a silicon chip, using the technology of a well established scanner mirror chips in combination with the realization of a reflective grating either through etching of the aluminium mirror layer or even a more sophisticated technology. The patented resonant drive realizes a mechanical angle of +/-7° with CMOS compatible voltages of approximately 20V. This technology leads to the realization of a set up close to a classical Czerny-Turner spectrometer using a single detector only. The device offers the capability to be scaled down to the size of a cigarette box. The spectrometer presented here was adjusted to 900...2500nm range. The scanning grating chip has either 500, 625 or 714 lines/mm. As detector serves a fast InGaAs photodiode, read out through a 12 Bit AD converter. The sinusoidal movement is unfolded by a signal processor (TI TMS320F2812) which also computes the spectrum. Acquired data can be shown by a display or transmitted to a host PC. System tests have been performed using infrared LEDs. Wavelengths have been 1300, 1400 or 1550nm for example. The spectrometer is working accurately. First result of micro shaped grating structures to enhance the sensitivity are presented.

  9. ISS Update: Alpha Magnetic Spectrometer

    NASA Video Gallery

    NASA Public Affairs Officer Kelly Humphries interviews Trent Martin, Johnson Space Center project manager for the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. Questions...

  10. Detector development for Jefferson Lab's 12 GeV Upgrade

    NASA Astrophysics Data System (ADS)

    Qiang, Yi

    2015-05-01

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers, the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.

  11. Detector development for Jefferson Lab's 12GeV Upgrade

    SciTech Connect

    Qiang, Yi

    2015-05-01

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers, the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.

  12. Detector development for Jefferson Lab's 12GeV Upgrade

    DOE PAGESBeta

    Qiang, Yi

    2015-05-01

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers,more » the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.« less

  13. Particle Spectrometers for FRIB

    NASA Astrophysics Data System (ADS)

    Amthor, A. M.

    2014-09-01

    FRIB promises to dramatically expand the variety of nuclear systems available for direct experimental study by providing rates of many rare isotopes orders of magnitude higher than those currently available. A new generation of experimental systems, including new particle spectrometers will be critical to our ability to take full advantage of the scientific opportunities offered by FRIB. The High-Rigidity Spectrometer (HRS) will allow for experiments with the most neutron-rich and short-lived isotopes produced by in-flight fragmentation at FRIB. The bending capability of the HRS (8 Tm) matches to the rigidity for which rare isotopes are produced at the highest intensity in the FRIB fragment separator. The experimental program will be focused on nuclear structure and astrophysics, and allow for the use of other cutting-edge detection systems for gamma, neutron, and charged-particle detection. Stopped and reaccelerated beam studies will be an important compliment to in-flight techniques at FRIB, providing world-unique, high quality, intense rare isotope beams at low energies up to and beyond the Coulomb barrier--with the completion of ReA12--and serving many of the science goals of the broader facility, from nuclear structure and astrophysics to applications. Two specialized recoil spectrometers are being developed for studies with reaccelerated beams. SECAR, the Separator for Capture Reactions, will be built following ReA3, coupled to a windowless gas jet target, JENSA, and will focus on radiative capture reactions for astrophysics, particularly those needed to improve our understanding of novae and X-ray bursts. A recoil separator following ReA12 is proposed to address a variety of physics cases based on fusion-evaporation, Coulomb excitation, transfer, and deep-inelastic reactions by providing a large angular, momentum and charge state acceptance; a high mass resolving power; and the flexibility to couple to a variety of auxiliary detector systems. Two designs

  14. Comet Ge-Wang

    NASA Astrophysics Data System (ADS)

    Ge, Yong-liang; Wang, Qi; Han, Tao

    1990-03-01

    Comet Ge-Wang (1988o) was discovered by GE Yong-liang and WANG Qi at Xinglong Station of Beijing Observatory on 1988 November 4. We collected 13 observations of this comet in China and abroad and calculated its orbit. It passed the perihelion on 1988 May 23. Ephemerides up to 1991 April are given.

  15. Comet Ge-Wang

    NASA Astrophysics Data System (ADS)

    Ge, Yong-Liang; Wang, Qi; Han, Tao

    1989-03-01

    Comet Ge-Wang (1988o) was discovered by GE Yong-liang and WANG Qi at Xinglong Station of Beijing Observatory on November 4, 1988. Thirteen observations of this comet were collected in China and abroad and calculated its orbit. It passed the perihelion on May 23, 1988. Ephemerides up to April 1991 are given.

  16. Photo ion spectrometer

    DOEpatents

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

    1989-12-26

    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.

  17. Photo ion spectrometer

    DOEpatents

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1989-01-01

    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.

  18. Coastal Research Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    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.

  19. Optical fiber smartphone spectrometer.

    PubMed

    Hossain, Md Arafat; Canning, John; Cook, Kevin; Jamalipour, Abbas

    2016-05-15

    An optical fiber-based smartphone spectrometer incorporating an endoscopic fiber bundle is demonstrated. The endoscope allows transmission of the smartphone camera LED light to a sample, removing complications from varying background illumination. The reflected spectra collected from a surface or interface is dispersed onto the camera CMOS using a reflecting diffraction grating. A spectral resolution as low as δλ∼2.0  nm over a bandwidth of Δλ∼250  nm is obtained using a slit width, ωslit=0.7  mm. The instrument has vast potential in a number of industrial applications including agricultural produce analysis. Spectral analysis of apples shows straightforward measurement of the pigments anthocyanins, carotenoid, and chlorophyll, all of which decrease with increasing storage time. PMID:27176971

  20. Cryogenic Neutron Spectrometer Development

    SciTech Connect

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

    2006-03-08

    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

  1. A Liquid-Cryogen-Free Superconducting Tunnel Junction X-ray Spectrometer for Astrobiology Research at the Synchrotron

    SciTech Connect

    Friedrich, S; Drury, O B; Hertrich, T; Hoehne, J

    2008-06-15

    Superconducting tunnel junctions (STJs) are being developed as energy-dispersive soft X-ray detectors, because they combine the high energy resolution of low-temperature detectors with the comparably high count rates of non-thermal devices. We have built a 36-pixel spectrometer based on 200 {micro}m x 200 {micro}m Nb-Al-AlOx-Al-Nb STJs. It offers an energy resolution of {approx}10 to 20 eV FWHM in the soft X-ray band below 1 keV, a solid angle coverage {Omega}/4{pi} {approx} 10{sup -3}, and can be operated at total rates up to {approx}10{sup 6} counts/s. For STJ operation by non-expert users, we have built a liquid-cryogen-free spectrometer with a mechanical pulse-tube cryocooler and a two-stage adiabatic demagnetization refrigerator. It is fully automated for cooldown to a base temperature of <30 mK in 15 hours, and has a hold time of >3 days between demagnetization cycles for STJ operation at 0.3 K. The STJ spectrometers are used for speciation measurements on dilute samples by fluorescence-detected X-ray absorption spectroscopy, and can achieve sensitivities below 100 ppm. We discuss the spectrometer performance in representative applications on metals in meteorites in the context of geological signatures of biological activity.

  2. Lunar orbital mass spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Lord, W. P.

    1971-01-01

    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.

  3. Analysis and implementation of a space resolving spherical crystal spectrometer for x-ray Thomson scattering experiments

    SciTech Connect

    Harding, E. C.; Ao, T.; Bailey, J. E.; Loisel, G.; Sinars, D. B.; Geissel, M.; Rochau, G. A.; Smith, I. C.

    2015-04-15

    The application of a space-resolving spectrometer to X-ray Thomson Scattering (XRTS) experiments has the potential to advance the study of warm dense matter. This has motivated the design of a spherical crystal spectrometer, which is a doubly focusing geometry with an overall high sensitivity and the capability of providing high-resolution, space-resolved spectra. A detailed analysis of the image fluence and crystal throughput in this geometry is carried out and analytical estimates of these quantities are presented. This analysis informed the design of a new spectrometer intended for future XRTS experiments on the Z-machine. The new spectrometer collects 6 keV x-rays with a spherically bent Ge (422) crystal and focuses the collected x-rays onto the Rowland circle. The spectrometer was built and then tested with a foam target. The resulting high-quality spectra prove that a spherical spectrometer is a viable diagnostic for XRTS experiments.

  4. Analysis and implementation of a space resolving spherical crystal spectrometer for x-ray Thomson scattering experiments.

    PubMed

    Harding, E C; Ao, T; Bailey, J E; Loisel, G; Sinars, D B; Geissel, M; Rochau, G A; Smith, I C

    2015-04-01

    The application of a space-resolving spectrometer to X-ray Thomson Scattering (XRTS) experiments has the potential to advance the study of warm dense matter. This has motivated the design of a spherical crystal spectrometer, which is a doubly focusing geometry with an overall high sensitivity and the capability of providing high-resolution, space-resolved spectra. A detailed analysis of the image fluence and crystal throughput in this geometry is carried out and analytical estimates of these quantities are presented. This analysis informed the design of a new spectrometer intended for future XRTS experiments on the Z-machine. The new spectrometer collects 6 keV x-rays with a spherically bent Ge (422) crystal and focuses the collected x-rays onto the Rowland circle. The spectrometer was built and then tested with a foam target. The resulting high-quality spectra prove that a spherical spectrometer is a viable diagnostic for XRTS experiments. PMID:25933859

  5. VEGAS: VErsatile GBT Astronomical Spectrometer

    NASA Astrophysics Data System (ADS)

    Bussa, Srikanth; VEGAS Development Team

    2012-01-01

    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.

  6. Nucleon spin physics using CEBAF at 11 GeV

    SciTech Connect

    Zein-Eddine Meziani

    2003-03-01

    We discuss key experiments that address some of the nucleon spin physics questions as part of the 12 GeV planning for the energy upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. These experiments take advantage of a highly polarized beam and the availability of polarized target namely {sup 3}He combined with a Medium Acceptance Spectrometer (MAD) in Hall A.

  7. Aerosol mobility size spectrometer

    DOEpatents

    Wang, Jian; Kulkarni, Pramod

    2007-11-20

    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.

  8. Cascaded interferometric imaging spectrometer.

    PubMed

    Swinyard, Bruce; Ferlet, Marc

    2007-09-01

    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 microm 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. PMID:17805378

  9. Photo ion spectrometer

    DOEpatents

    Gruen, Dieter M.; Young, Charles E.; Pellin, Michael J.

    1989-01-01

    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.

  10. Photo ion spectrometer

    DOEpatents

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

    1989-08-08

    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.

  11. Neutron range spectrometer

    DOEpatents

    Manglos, Stephen H.

    1989-06-06

    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.

  12. First Measurement of the Gerasimov-Drell-Hearn Sum Rule for 1H from 0.7 to 1.8 GeV at ELSA.

    PubMed

    Dutz, H; Helbing, K; Krimmer, J; Speckner, T; Zeitler, G; Ahrens, J; Altieri, S; Annand, J R M; Anton, G; Arends, H-J; Beck, R; Bock, A; Bradtke, C; Braghieri, A; v Drachenfels, W; Frommberger, F; Godo, M; Goertz, S; Grabmayr, P; Hasegawa, S; Hansen, K; Harmsen, J; Heid, E; Hillert, W; Holvoet, H; Horikawa, N; Iwata, T; Van Hoorebeke, L; d'Hose, N; Jennewein, P; Kiel, B; Klein, F; Kondratiev, R; Lang, M; Lannoy, B; Leukel, R; Lisin, V; Menze, D; Meyer, W; Michel, T; Naumann, J; Panzeri, A; Pedroni, P; Pinelli, T; Preobrajenski, I; Radtke, E; Reicherz, G; Rohlof, C; Rostomyan, T; Sauer, M; Schoch, B; Schumacher, M; Tamas, G; Thomas, A; van de Vyver, R; Weihofen, W; Zapadtka, F

    2003-11-01

    To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb. PMID:14611575

  13. Method for calibrating mass spectrometers

    DOEpatents

    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

    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.

  14. Multiple order common path spectrometer

    NASA Technical Reports Server (NTRS)

    Newbury, Amy B. (Inventor)

    2010-01-01

    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.

  15. Coastal Research Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    2002-01-01

    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.

  16. Micromachined Slits for Imaging Spectrometers

    NASA Technical Reports Server (NTRS)

    Wilson, Daniel; Kenny, James; White, Victor

    2008-01-01

    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.

  17. Alpha Magnetic Spectrometer (AMS) Overview

    NASA Video Gallery

    The Alpha Magnetic Spectrometer (AMS) is flying to the station on STS-134. The AMS experiment is a state-of-the-art particle physics detector being operated by an international team composed of 60 ...

  18. Fast-neutron spectrometer developments

    NASA Technical Reports Server (NTRS)

    Moler, R. B.; Zagotta, W. E.; Baker, S. I.

    1973-01-01

    Li6 sandwich-type neutron spectrometer is equipped with proportional counter for particle identification. System uses current-sensitive preamplifiers to minimize pile-up of gamma-ray and particle pulses.

  19. Versatile cluster based photoelectron spectrometer

    SciTech Connect

    Knappenberger, K. L. Jr.; Jones, C. E. Jr.; Sobhy, M. A.; Castleman, A. W. Jr.

    2006-12-15

    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.

  20. The GRAVITY spectrometers: optical qualification

    NASA Astrophysics Data System (ADS)

    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

    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 μas 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 μm) 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 μm2) for the Science channel and in 1 pixel (24 × 24 μm) in the Fringe Tracking channel. In Section 1, we present

  1. Resonance-filtered beam spectrometer

    SciTech Connect

    Brugger, R.M.; Taylor, A.D.; Olsen, C.E.; Goldstone, J.A.; Soper, A.K.

    1982-01-01

    A new inelastic neutron scattering spectrometer which operates in the range 1 eV to 15 eV has been developed at the Los Alamos pulsed spallation source WNR. Based on a nuclear resonance filtering the beam, the concept has been tested in direct, inverted and sample geometries. A number of resonance filters have been tested to determine their effectiveness. The spectrometer is described and examples of data are presented.

  2. Preliminary Analysis of the Multisphere Neutron Spectrometer

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

  3. Coastal Research Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    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

  4. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Macenka, Steven A.; Chrisp, Michael P.

    1988-01-01

    The development of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has been completed at JPL. This paper outlines the functional requirements of the spectrometer optics subsystem, and describes the spectrometer optical design. The optical subsystem performance is shown in terms of spectral modulation transfer functions, radial energy distributions, and system transmission at selected wavelengths for the four spectrometers. An outline of the spectrometer alignment is included.

  5. Imaging spectrometers for remote sensing from space

    NASA Technical Reports Server (NTRS)

    Chrisp, M. P.; Breckinridge, J. B.; Macenka, S. A.; Page, N. A.

    1986-01-01

    Three imaging spectrometers and two camera systems for remote sensing are described. Two of the imaging spectrometers are versions of the Visible and Infrared Mapping Spectrometer (VIMS) for Mars Observer and the Comet Rendezvous Asteroid Flyby (CRAF) mission. The other spectrometer is the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) which is currently under construction. The optical imaging systems are the wide angle and narrow angle cameras for the CRAF mission.

  6. A Novel MOEMS NIR Spectrometer

    NASA Astrophysics Data System (ADS)

    Zhihai, Zhang; Xiangxia, Mo; Yuanjun, Guo; Wei, Wang

    In order to detect luminous intensity of light signal in NIR (Near-infrared) wavelength range, a novel MOEMS(Micro-Opto-Electro-Mechanical Systems) NIR spectrometer is proposed in the paper. It uses DMD (Digital Micro-mirror Device) to band filter the input spectrum. The merits of DMD are small size, low price and high scan speed. Especially, when DMD acts as a Hadamard Transform encoding mask, the SNR (signal-to-noise-ratio) can be improved by multiplexing the light intensities. The structure and the theory of this spectrometer are analyzed. The Hadamard-S matrix and mask of 63-order and 127-order are designed. The output spectrum of the new spectrometer coincides with experimental result of Shimadzu spectrometer. The resolution of the new spectrometer is 19 nm over the spectral range between 900∼1700 nm while single scan time is only 2.4S. The SNR is 44.67:1. The size of optical path is 70mm × 130 mm, and it has a weight less than 1Kg. It can meet the requirement of real time measurement and portable application.

  7. Resolution-enhanced Mapping Spectrometer

    NASA Technical Reports Server (NTRS)

    Kumer, J. B.; Aubrun, J. N.; Rosenberg, W. J.; Roche, A. E.

    1993-01-01

    A familiar mapping spectrometer implementation utilizes two dimensional detector arrays with spectral dispersion along one direction and spatial along the other. Spectral images are formed by spatially scanning across the scene (i.e., push-broom scanning). For imaging grating and prism spectrometers, the slit is perpendicular to the spatial scan direction. For spectrometers utilizing linearly variable focal-plane-mounted filters the spatial scan direction is perpendicular to the direction of spectral variation. These spectrometers share the common limitation that the number of spectral resolution elements is given by the number of pixels along the spectral (or dispersive) direction. Resolution enhancement by first passing the light input to the spectrometer through a scanned etalon or Michelson is discussed. Thus, while a detector element is scanned through a spatial resolution element of the scene, it is also temporally sampled. The analysis for all the pixels in the dispersive direction is addressed. Several specific examples are discussed. The alternate use of a Michelson for the same enhancement purpose is also discussed. Suitable for weight constrained deep space missions, hardware systems were developed including actuators, sensor, and electronics such that low-resolution etalons with performance required for implementation would weigh less than one pound.

  8. A balloon-borne ionization spectrometer with very large aperture for the detection of high energy cosmic rays

    NASA Technical Reports Server (NTRS)

    Atallah, K.; Modlinger, A.; Schmidt, W. K. H.; Cleghorn, T. F.

    1975-01-01

    A balloon experiment which was used to determine the chemical composition of very high-energy cosmic rays up to and beyond 100 GeV/nucleon is described. The detector had a geometric factor of 1 sq m sr and a total weight on the balloon of 2100 kg. The apparatus consisted of an ionization spectrometer, spark chambers, and plastic scintillation and Cherenkov counters. It was calibrated at CERN up to 24 GeV/c protons and at DESY up to 7 GeV/c electrons. In October 1972 it was flown successfully on a stratospheric balloon.

  9. Mini ion trap mass spectrometer

    DOEpatents

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

    1995-09-19

    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.

  10. Mini ion trap mass spectrometer

    DOEpatents

    Dietrich, Daniel D.; Keville, Robert F.

    1995-01-01

    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.

  11. Mobile spectrometer measures radar backscatter

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

  12. Multichannel Spectrometer of Time Distribution

    NASA Astrophysics Data System (ADS)

    Akindinova, E. V.; Babenko, A. G.; Vakhtel, V. M.; Evseev, N. A.; Rabotkin, V. A.; Kharitonova, D. D.

    2015-06-01

    For research and control of characteristics of radiation fluxes, radioactive sources in particular, for example, in paper [1], a spectrometer and methods of data measurement and processing based on the multichannel counter of time intervals of accident events appearance (impulses of particle detector) MC-2A (SPC "ASPECT") were created. The spectrometer has four independent channels of registration of time intervals of impulses appearance and correspondent amplitude and spectrometric channels for control along the energy spectra of the operation stationarity of paths of each of the channels from the detector to the amplifier. The registration of alpha-radiation is carried out by the semiconductor detectors with energy resolution of 16-30 keV. Using a spectrometer there have been taken measurements of oscillations of alpha-radiation 239-Pu flux intensity with a subsequent autocorrelative statistical analysis of the time series of readings.

  13. Thermal Infrared Profiling Spectrometer (TIPS)

    NASA Astrophysics Data System (ADS)

    Lanzl, Franz; Miosga, G.; Lehmann, F.; Richter, R.; Tank, V.

    1989-12-01

    An airborne/spaceborne sensor concept developed for scientific observations in remote sensing of the earth surface is presented. The spectrometer design is based on a fast scanning Fourier spectrometer using a rotating retroreflector. The spectrometer covers the 3-13-micron band with a spectral resolution of 5/cm. The measured signal is an interferogramm, while derived quantities are spectral emissivity, spectral radiance, and surface temperature. The optical system consists of an aperture-filling plane tilting mirror to provide off-nadir observation and calibration modes. The collecting mirror focal length and the detector area yield an instantaneous field of view of 1.2 mrad, noise equivalent temperature resolution of 0.004 K, and a noise equivalent change in emissivity of 0.0006. The simulation results of signal-to-noise performance of the TIPS are presented and discussed.

  14. Identified particles in Au+Au collisions at S=200 GeV

    NASA Astrophysics Data System (ADS)

    Phobos Collaboration; Wosiek, Barbara; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Ballintijn, M.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2003-03-01

    The yields of identified particles have been measured at RHIC for Au+Au collisions at S=200 GeV using the PHOBOS spectrometer. The ratios of antiparticle to particle yields near mid-rapidity are presented. The first measurements of the invariant yields of charged pions, kaons and protons at very low transverse momenta are also shown.

  15. The GRAVITY spectrometers: thermal behaviour

    NASA Astrophysics Data System (ADS)

    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

    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 10μas 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.

  16. JPL Fourier transform ultraviolet spectrometer

    NASA Technical Reports Server (NTRS)

    Cageao, R. P.; Friedl, R. R.; Sander, Stanley P.; Yung, Y. L.

    1994-01-01

    The Fourier Transform Ultraviolet Spectrometer (FTUVS) is a new high resolution interferometric spectrometer for multiple-species detection in the UV, visible and near-IR. As an OH sensor, measurements can be carried out by remote sensing (limb emission and column absorption), or in-situ sensing (long-path absorption or laser-induced fluorescence). As a high resolution detector in a high repetition rate (greater than 10 kHz) LIF system, OH fluorescence can be discriminated against non-resonant background emission and laser scatter, permitting (0, 0) excitation.

  17. A cometary ion mass spectrometer

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

  18. Forward spectrometers at the SSC

    SciTech Connect

    Bjorken, J.D.

    1986-01-01

    Most of SSC phase space and a great deal of physics potential is in the forward/backward region (absolute value of theta < 100 mrad). Comprehensive open-geometry spectrometers are feasible and very cost effective. Examples of such devices are sketched. Because such spectrometers are very long and may operate at high ..beta.. and longer bunch spacing, they impact now on SSC interaction - region design. The data acquisition load is as heavy as for central detectors, although there may be less emphasis on speed and more emphasis on sophisticated parallel and/or distributed processing for event selection, as well as on high-capacity buffering.

  19. Towed seabed gamma ray spectrometer

    SciTech Connect

    Jones, D.G. )

    1994-08-01

    For more than 50 years, the measurement of radioactivity has been used for onshore geological surveys and in laboratories. The British Geological Survey (BGS) has extended the use of this type of equipment to the marine environment with the development of seabed gamma ray spectrometer systems. The present seabed gamma ray spectrometer, known as the Eel, has been successfully used for sediment and solid rock mapping, mineral exploration, and radioactive pollution studies. The range of applications for the system continues to expand. This paper examines the technological aspects of the Eel and some of the applications for which it has been used.

  20. Portable smartphone optical fibre spectrometer

    NASA Astrophysics Data System (ADS)

    Hossain, Md. Arafat; Canning, John; Cook, Kevin; Jamalipour, Abbas

    2015-09-01

    A low cost, optical fibre based spectrometer has been developed on a smartphone platform for field-portable spectral analysis. Light of visible wavelength is collected using a multimode optical fibre and diffracted by a low cost nanoimprinted diffraction grating. A measurement range over 300 nm span (λ = 400 to 700 nm) is obtained using the smartphone CMOS chip. The spectral resolution is Δλ ~ 0.42 nm/screen pixel. A customized Android application processed the spectra on the same platform and shares with other devices. The results compare well with commercially available spectrometer.

  1. The Bruny Island Radio Spectrometer

    NASA Astrophysics Data System (ADS)

    Erickson, W. C.

    1997-11-01

    A radio spectrometer has been built on Bruny Island, south of Hobart, for the study of solar bursts in the rarely observed frequency range from 3 to 20 MHz. This spectrometer is an adaptive device that employs digital techniques to avoid most of the strong terrestrial interference prevalent in this frequency range. The residual interference that cannot be avoided is excised during off-line processing. As a result, successful observations are made down to the minimum frequency that can propagate through the ionosphere to the antenna. This minimum frequency depends upon the zenith distance of the Sun and it is usually between 4 and 8 MHz.

  2. Mass spectrometers and atomic oxygen

    NASA Technical Reports Server (NTRS)

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

    1987-01-01

    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.

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

    SciTech Connect

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

    2007-04-15

    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.

  4. GeV Electron Beams from a Capillary Discharge Guided Laser Plasma Accelerator

    SciTech Connect

    Nakamura, Kei; Gonsalves, Anthony; Panasenko, Dmitriy; Lin, Chen; Toth, Csaba; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Leemans, Wim

    2010-07-08

    Laser plasma acceleration (LPA) up to 1 GeV has been realized at Lawrence Berkeley National Laboratory by using a capillary discharge waveguide. In this paper, the capillary discharge guided LPA system including a broadband single-shot electron spectrometer is described. The spectrometer was designed specifically for LPA experiments and has amomentumacceptance of 0.01 - 1.1 GeV/c with a percent level resolution. Experiments using a 33 mm long, 300 mu m diameter capillary demonstrated the generation of high energy electron beams up to 1 GeV. By de-tuning discharge delay from optimum guiding performance, selftrapping and acceleration were found to be stabilized producing 460 MeV electron beams.

  5. Si/Ge intermixing during Ge Stranski–Krastanov growth

    PubMed Central

    Hoummada, Khalid; Ronda, Antoine; Mangelinck, Dominique; Berbezier, Isabelle

    2014-01-01

    Summary The Stranski–Krastanov growth of Ge islands on Si(001) has been widely studied. The morphology changes of Ge islands during growth, from nucleation to hut/island formation and growth, followed by hut-to-dome island transformation and dislocation nucleation of domes, have been well described, even at the atomic scale, using techniques such as scanning tunneling microscopy and transmission electron microscopy. Although it is known that these islands do not consist of pure Ge (due to Si/Ge intermixing), the composition of the Ge islands is not precisely known. In the present work, atom probe tomography was used to study the composition of buried dome islands at the atomic scale, in the three-dimensional space. The core of the island was shown to contain about 55 atom % Ge, while the Ge composition surrounding this core decreases rapidly in all directions in the islands to reach a Ge concentration of about 15 atom %. The Ge distribution in the islands follows a cylindrical symmetry and Ge segregation is observed only in the {113} facets of the islands. The Ge composition of the wetting layer is not homogeneous, varying from 5 to 30 atom %. PMID:25551065

  6. Imaging IR spectrometer, phase 2

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

    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.

  7. IPNS-I chopper spectrometers

    SciTech Connect

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

    1982-01-01

    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.

  8. Alpha proton x ray spectrometer

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    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.

  9. Time of flight mass spectrometer

    DOEpatents

    Ulbricht, Jr., William H.

    1984-01-01

    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.

  10. Tracking System for Infrared Spectrometer

    NASA Technical Reports Server (NTRS)

    Johnson, R. A.; Webster, C. R.; Menzies, R. T.; Morrison, G. B.; Riccio, J. H.

    1986-01-01

    Visible laser tracking system for infrared laser spectometer keeps probe infrared laser beam aimed at moving reflector, thereby keeping reflector image and return laser beam within spectrometer field of view. System includes tracking mirror tilted by stepping motors under microprocessor control to deflect beams toward continually changing reflector position.

  11. MICE Spectrometer Magnet System Progress

    SciTech Connect

    Green, Michael A.; Virostek, Steve P.

    2007-08-27

    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.

  12. A simple digital TDPAC spectrometer

    NASA Astrophysics Data System (ADS)

    Webb, T. A.; Nikkinen, Leo; Gallego, Juan; Ryan, D. H.

    2013-05-01

    We present a simplified digital time differential perturbed γ - γ angular correlation (TDPAC) spectrometer that demonstrates that such instruments can be built using primarily commercial components and with relatively modest coding effort. The system handles data rates of 70 kcps/detector with a timing resolution of better than 500 ps, and has been used with both 111In and 181Hf.

  13. Convex Diffraction Grating Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Chrisp, Michael P. (Inventor)

    1999-01-01

    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.

  14. Acoustically-tuned optical spectrometer

    NASA Technical Reports Server (NTRS)

    Sklar, E.

    1981-01-01

    Lens arrangement corrects for aberrations and gives resolution of 0.7 seconds of arc. In spectrometer, light from telescope is relayed by doublet lens to acoustically tuned optical filter. Selected wavelengths are relayed by triplet lens to charge coupled device camera. Intervening cylindrical lens, tilted at 12 degree angle, corrects for astigmatism and coma introduced by two element birefringent crystal in filter.

  15. The Sandwich spectrometer for ultra low-level gamma-ray spectrometry.

    PubMed

    Wieslander, J S Elisabeth; Hult, Mikael; Gasparro, Joël; Marissens, Gerd; Misiaszek, Marcin; Preusse, Werner

    2009-05-01

    The technical details and performance of the newly developed Sandwich spectrometer for ultra low-level gamma-ray spectrometry are presented. The spectrometer, which consists of two HPGe detectors, an active muon shield and a lead/copper shield with a convenient and rapid opening mechanism, is located in an underground laboratory at a depth of 500 m water equivalent. The data is collected in list mode, which enables off-line data analysis to identify muon-induced events and possible Ge detector crosstalk due to Compton scattering. The background count-rate from 40 to 2700 keV normalised to the mass of the Ge crystals is 220 day(-1)kg(-1). PMID:19246202

  16. Synthesis of Epitaxial Films Based on Ge-Si-Sn Materials with Ge/GeSn, Ge/GeSiSn, and GeSn/GeSiSn Heterojunctions

    NASA Astrophysics Data System (ADS)

    Timofeev, V. A.; Kokhanenko, A. P.; Nikiforov, A. I.; Mashanov, V. I.; Tuktamyshev, A. R.; Loshkarev, I. D.

    2015-11-01

    Results of investigations into the synthesis of heterostructures based on Ge-Si-Sn materials by the method of low-temperature molecular beam epitaxy are presented. The formation of epitaxial films during structure growth has been controlled by the reflection high-energy electron diffraction method. Films with Ge/GeSn, Ge/GeSiSn, and GeSn/GeSiSn heterojunctions are grown with Sn content changing from 2 to 10 % at temperatures in the interval 150-350°C. The stressed state, the composition, and the lattice parameter are studied by the x-ray diffraction method using Omega-scan curves and reciprocal space maps. A tensile strain in the Ge film during Ge/Ge0.9Sn0.1/Si structure growth has reached 0.86%.

  17. Barrel Calorimeter for the Hall D Spectrometer

    SciTech Connect

    David Urner

    1998-06-01

    The barrel calorimeter for the hall D spectrometer is discussed for standard pointing geometry and a parallel geometry using Lead Scintillating fibres as active material. A comparison with a CSI spectrometer is shown.

  18. Electron/proton spectrometer certification documentation analyses

    NASA Technical Reports Server (NTRS)

    Gleeson, P.

    1972-01-01

    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.

  19. Sample rotating turntable kit for infrared spectrometers

    DOEpatents

    Eckels, Joel Del; Klunder, Gregory L.

    2008-03-04

    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.

  20. Measuring Transmission Efficiencies Of Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Srivastava, Santosh K.

    1989-01-01

    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.

  1. Electron spectrometer for gas-phase spectroscopy

    SciTech Connect

    Bozek, J.D.; Schlachter, A.S.

    1997-04-01

    An electron spectrometer for high-resolution spectroscopy of gaseous samples using synchrotron radiation has been designed and constructed. The spectrometer consists of a gas cell, cylindrical electrostatic lens, spherical-sector electron energy analyzer, position-sensitive detector and associated power supplies, electronics and vacuum pumps. Details of the spectrometer design are presented together with some representative spectra.

  2. Advanced Mass Spectrometers for Hydrogen Isotope Analyses

    SciTech Connect

    Chastagner, P.

    2001-08-01

    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.

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

    PubMed

    Bakeman, M S; van Tilborg, J; Sokollik, T; Baum, D; Ybarrolaza, N; Duarte, R; Toth, C; Leemans, W P

    2010-10-01

    We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range. PMID:21034012

  4. Cosmic ray studies with a gas Cherenkov counter in association with an ionization spectrometer

    NASA Technical Reports Server (NTRS)

    Balasubrahmanyan, V. K.; Ormes, J. F.; Arens, J. F.; Siohan, F.; Yodh, G. B.; Simon, M.; Spiegelhauer, H.

    1980-01-01

    The results from a balloon-borne gas Cherenkov counter (threshold 16.5 GeV/nucleon) and an ionization spectrometer are presented. The gas Cherenkov counter provides an absolute energy distribution for the response of the calorimeter for 5 or = Z 26 nuclei of cosmic rays. The contribution of scintillation to the gas Cherenkov pulse height was obtained by independently selecting particles below the gas Cherenkov threshold using the ionization spectrometer. Energy spectra were derived by minimizing the chi squared between Monte Carlo simulted data and flight data. Best fit power laws, dN/dE = AE-gamma, were determined for C, N, O, Ne, Mg, and Si. The power laws, all consistent with E (-2.7) are not good fits to the data. A better fit is obtained using the spectrum derived from the spectrometer. The data from the ionization calorimeter and the gas Cherenkov are thus completely self-consistent.

  5. Cosmic ray studies with a gas Cerenkov counter in association with an ionization spectrometer

    NASA Technical Reports Server (NTRS)

    Balasubrahmanyan, V. K.; Ormes, J. F.; Arens, J. F.; Siohan, F.; Simon, M.; Spiegelhauer, H.; Yodh, G. B.

    1980-01-01

    The results from a balloon-borne gas Cerenkov counter (threshold 16.5 GeV/nuc) and an ionization spectrometer are presented. The gas Cerenkov counter provides an absolute energy calibration for the response of the calorimeter for the Z range of 5-26 nuclei of cosmic rays. The contribution of scintillation to the gas Cerenkov pulse height has been obtained by independently selecting particles below the gas Cerenkov threshold using the ionization spectrometer. Energy spectra were derived by minimizing the chi-squared between a Monte Carlo simulated data and flight data. Best fit power laws were determined for C, N, O, Ne, Mg, and Si. The power laws, all consistent with E exp-2.7, are not good fits to the data. A better fit is obtained using the spectrum derived from the spectrometer.

  6. Concerning the Spatial Heterodyne Spectrometer.

    PubMed

    Lenzner, Matthias; Diels, Jean-Claude

    2016-01-25

    A modified Spatial Heterodyne Spectrometer (SHS) is used for measuring atomic emission spectra with high resolution. This device is basically a Fourier Transform Spectrometer, but the Fourier transform is taken in the directions perpendicular to the optical propagation and heterodyned around one preset wavelength. In recent descriptions of this device, one specific phenomenon - the tilt of the energy front of wave packets when diffracted from a grating - was neglected. This led to an overestimate of the resolving power of this spectrograph, especially in situations when the coherence length of the radiation under test is in the order of the effective aperture of the device. The limits of usability are shown here together with some measurements of known spectral lines. PMID:26832561

  7. Concerning the Spatial Heterodyne Spectrometer

    DOE PAGESBeta

    Lenzner, Matthias; Diels, Jean -Claude

    2016-01-22

    A modified Spatial Heterodyne Spectrometer (SHS) is used for measuring atomic emission spectra with high resolution. This device is basically a Fourier Transform Spectrometer, but the Fourier transform is taken in the directions perpendicular to the optical propagation and heterodyned around one preset wavelength. In recent descriptions of this device, one specific phenomenon - the tilt of the energy front of wave packets when diffracted from a grating - was neglected. This led to an overestimate of the resolving power of this spectrograph, especially in situations when the coherence length of the radiation under test is in the order ofmore » the effective aperture of the device. In conclusion, the limits of usability are shown here together with some measurements of known spectral lines.« less

  8. Temporal dispersion of a spectrometer.

    PubMed

    Visco, A; Drake, R P; Froula, D H; Glenzer, S H; Pollock, B B

    2008-10-01

    The temporal dispersion of an optical spectrometer has been characterized for a variety of conditions related to optical diagnostics to be fielded at the National Ignition Facility (e.g., full-aperture backscatter station, Thomson scattering). Significant time smear is introduced into these systems by the path length difference through the spectrometer. The temporal resolution is shown to depend only on the order of the grating, wavelength, and the number of grooves illuminated. To enhance the temporal resolution, the spectral gratings can be masked limiting the number of grooves illuminated. Experiments have been conducted to verify these calculations. The size and shape of masks are investigated and correlated with the exact shape of the temporal instrument function, which is required when interpreting temporally resolved data. The experiments used a 300 fs laser pulse and a picosecond optical streak camera to determine the temporal dispersion. This was done for multiple spectral orders, gratings, and optical masks. PMID:19044687

  9. On-chip plasmonic spectrometer.

    PubMed

    Tsur, Yuval; Arie, Ady

    2016-08-01

    We report a numerical and experimental study of an on-chip optical spectrometer, utilizing propagating surface plasmon polaritons in the telecom spectral range. The device is based on two holographic gratings, one for coupling, and the other for decoupling free-space radiation with the surface plasmons. This 800 μm×100 μm on-chip spectrometer resolves 17 channels spectrally separated by 3.1 nm, spanning a freely tunable spectral window, and is based on standard lithography fabrication technology. We propose two potential applications for this new device; the first employs the holographic control over the amplitude and phase of the input spectrum, for intrinsically filtering unwanted frequencies, like pump radiation in Raman spectroscopy. The second prospect utilizes the unique plasmonic field enhancement at the metal-dielectric boundary for the spectral analysis of very small samples (e.g., Mie scatterers) placed between the two gratings. PMID:27472609

  10. Imaging X-ray spectrometer

    NASA Astrophysics Data System (ADS)

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

    1984-09-01

    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.

  11. Exploiting a Transmission Grating Spectrometer

    SciTech Connect

    Ronald E. Bell

    2004-12-08

    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.

  12. Imaging X-ray spectrometer

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

  13. Axial field spectrometer at the CERN ISR

    SciTech Connect

    Gordon, H.; Hogue, R.; Killian, T.

    1981-01-01

    The Axial Field Spectrometer (AFS) was recently brought into operation at the CERN ISR. It is being exploited in a wide-ranging program to study different aspects of those proton-proton or proton-antiproton collisions which are characterized by a large transverse momentum (p/sub T/). Examples include the measurement of inclusive distributions of identified high p/sub T/ hadrons, and the study of event structures characterized by a large transverse energy (E/sub T/) or the production of one or several high-p/sub T/ electrons or photons. The experimental approach to this program emphasizes integration of advanced magnetic spectroscopy with state-of-the-art calorimetry. These techniques are fully exploited to provide maximal information on all particles produced. In addition, information from these detectors is used in new ways for on-line event triggering and filtering; this allows even very rare events to be selected with high efficiency, an essential prerequisite for studies at a high-luminosity hadron collider, such as the ISR. Considerable modularity of the detectors was sought. Apart from clear advantages of construction, debugging, running, and servicing of such components, modularity provides ease for addition or reconfiguration of the system to emphasize the study of specific final states. At present, for example, a 1 sr Cerenkov detector system allows hadron identification up to p approx. = 12 GeV/c; liquid-argon electromagnetic calorimeters and a uranium-scintillator calorimeter (Hexagon) are used for a study of events containing direct photons.

  14. Amorphous Ge bipolar blocking contacts on Ge detectors

    SciTech Connect

    Luke, P.N.; Cork, C.P.; Madden, N.W.; Rossington, C.S.; Wesela, M.F.

    1991-10-01

    Semiconductor nuclear radiation detectors are usually operated in a full depletion mode and blocking contacts are required to maintain low leakage currents and high electric fields for charge collection. Blocking contacts on Ge detectors typically consist of n-type contacts formed by lithium diffusion and p-type contacts formed by boron ion implantation. Electrical contacts formed using sputtered amorphous Ge (a-Ge) films on high-purity Ge crystals were found to exhibit good blocking behavior in both polarities with low leakage currents. The a-Ge contacts have thin dead layers associated with them and can be used in place of lithium-diffused, ion-implanted or Schottky barrier contacts on Ge radiation detectors. Multi-electrode detectors can be fabricated with very simple processing steps using these contacts. 12 refs.

  15. Characteristics of Sn segregation in Ge/GeSn heterostructures

    NASA Astrophysics Data System (ADS)

    Li, H.; Chang, C.; Chen, T. P.; Cheng, H. H.; Shi, Z. W.; Chen, H.

    2014-10-01

    We report an investigation of Sn segregation in Ge/GeSn heterostructures occurred during the growth by molecular beam epitaxy. The measured Sn profile in the Ge layer shows that: (a) the Sn concentration decreases rapidly near the Ge/GeSn interface, and (b) when moving away from the interface, the Sn concentration reduced with a much slower rate. The 1/e decay lengths of the present system are much longer than those of the conventional group IV system of Ge segregation in the Si overlayer because of the smaller kinetic potential as modeled by a self-limited two-state exchange scheme. The demonstration of the Sn segregation shows the material characteristics of the heterostructure, which are needed for the investigation of its optical properties.

  16. Ge Nanocluster Enhanced Er Photoluminescence

    NASA Astrophysics Data System (ADS)

    Guzman, Julian; Chrzan, Daryl C.; Haller, Eugene E.

    2010-03-01

    We investigated the enhancement of the Er^3+ photoluminescence (PL) at 1540 nm by the incorporation of Ge nanoclusters into Er-doped silica using ion beams. We found that the Er^3+ PL enhancement is due to the presence of Ge and not to the radiation damage from the ion-implantation process. We determined that the Er^3+ PL depends on the Ge content, postgrowth annealing, and crystallinity of the Ge nanoclusters. Furthermore, we observed that the Er^3+ PL signal is maximized after annealing at 685 C for 1 h. This is the temperature at which Ge nanoclusters begin to crystallize. Transmission electron microscopy studies were conducted to determine the size distribution of the Ge nanoclusters. Moreover, extended X-ray absorption fine structure measurements performed at the Ge-K and Er-LIII edges revealed that there is negligible Ge-Er bonding. This suggests that Er is either fully oxidized or that it is not located in the Ge nanoclusters. Therefore, we believe that the energy transfer process from the Ge nanoclusters to the Er ions occurs through a non-optical resonant dipole transfer (F"orster ProcessfootnotetextT. F"orster, Discuss. Faraday Soc. 27, 7 (1959). similar to what has been proposed for the Si nanocrystal case.footnotetextM. Fujii, M. Yoshida, S. Hayashi, and K. Yamamoto, J. Appl. Phys. 84, 4525 (1998).

  17. Gamma-ray spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Arnold, J. R.; Peterson, L. E.; Metzger, A. E.; Trombka, J. I.

    1972-01-01

    The experiments in gamma-ray spectrometry to determine the geochemical composition of the lunar surface are reported. The theory is discussed of discrete energy lines of natural radioactivity, and the lines resulting from the bombardment of the lunar surface by high energy cosmic rays. The gamma-ray spectrometer used in lunar orbit and during transearth coast is described, and a preliminary analysis of the results is presented.

  18. Spectrometers for Beta Decay Electrons

    NASA Astrophysics Data System (ADS)

    Jiang, Yong; Hirshfield, Jay

    2015-04-01

    Inspired by the neutrino mass direct measurement experiment Project 8, precision spectrometers are proposed to simultaneously measure energy and momentum of beta-decay electrons produced in rare nuclear events with improved energy resolution. For detecting single beta decay electrons near the end-point from a gaseous source such as tritium, one type of spectrometer is proposed to utilize stimulated cyclotron resonance interaction of microwaves with electrons in a waveguide immersed in a magnetic mirror. In the external RF fields, on-resonance electrons will satisfy both the cyclotron resonance condition and waveguide dispersion relationship. By correlating the resonances at two waveguide modes, one can associate the frequencies with both the energy and longitudinal momentum of an on-resonance electron to account for the Doppler shifts. For detecting neutrino-less double-beta decay, another spectrometer is proposed with thin foil of double-beta-allowed material immersed in a magnetic field, and RF antenna array for detection of synchrotron radiation from electrons. It utilizes the correlation between the antenna signals including higher harmonics of radiation to reconstruct the total energy distribution.

  19. Landsat swath imaging spectrometer design

    NASA Astrophysics Data System (ADS)

    Mouroulis, Pantazis; Green, Robert O.; Van Gorp, Byron; Moore, Lori B.; Wilson, Daniel W.; Bender, Holly A.

    2016-01-01

    This paper describes the design of a high-throughput and high-uniformity pushbroom imaging spectrometer and telescope system that is capable of Landsat swath and resolution while providing better than 10 nm per pixel spectral resolution over the full visible to short-wave infrared band. The design is based on a 3200×480 element×18 μm pixel size focal plane array, two of which are utilized to cover the full swath. At an optical speed of F/1.8, the system is the fastest proposed to date to our knowledge. The utilization of only two Dyson-type spectrometer modules fed from the same telescope reduces system complexity while providing a solution within achievable detector technology. Two telescope designs are shown to achieve the required swath and resolution from different altitudes. Predictions of complete system response are shown. Also, it is shown that detailed ghost analysis is a requirement for this type of spectrometer and forms an essential part of a complete design.

  20. Thermal Infrared Profiling Spectrometer (TIPS)

    NASA Astrophysics Data System (ADS)

    Lanzl, Franz; Miosga, Gerhard; Lehmann, Frank; Richter, Rudolf; Tank, Volker; Boehl, R.

    1990-01-01

    The Thermal Infrared Profiling Spectrometer (TIPS) is an airborne/spaceborne sensor concept developed at DLR-Institute for Optoelectronics for scientific observations in remote sensing of the earth surface. The patented spectrometer design is based on a fast scanning Fourier spectrometer (FSM) using a rotating retroreflector to achieve the appropriate path alteration thus avoiding the usual linear movement of one of the mirrors in an conventional Michelson interferometer. The spectral band covers the 3 - 13 μm band with a spectral resolution of 5 cm-1 (50 nm at 10 μm). The measured signal is an interferogramm, derived quantities are spectral emissivity, spectral radiance and surface temperature. The optical system consists of an aperture filling plane tilting mirror to provide off-nadir observation and calibration mode. The collecting mirror focal length and the detector area yields an instantaneous field of view (ifov) of 1.2 mrad, noise equivalent temperature resolution of 0.04K (300K), and a noise equivalent change in emissivity Δɛof 6 x 10-4. Calibration is performed by two aperture filling area blackbodies at two different temperatures. An extensive simulation of signal/noise performance of the TIPS has been evaluated by means of the simulation programm SENSAT9, developed by DI.R. This simulation comprises the sensor performance, typical variations of atmospheric conditions and selected spectra from ground surfaces. Results of this simulation are discussed and a description of the sensor is presented.

  1. APPROACHING CRYOGENIC GE PERFORMANCE WITH PELTIER COOLED CDTE

    SciTech Connect

    Khusainov, A. K.; Iwanczyk, J. S.; Patt, B. E.; Prirogov, A. M.; Vo, Duc T.

    2001-01-01

    A new class of hand-held, portable spectrometers based on large area (lcm2) CdTe detectors of thickness up to 3mm has been demonstrated to produce energy resolution of between 0.3 and 0.5% FWHM at 662 keV. The system uses a charge loss correction circuit for improved efficiency, and detector temperature stabilization to ensure consistent operation of the detector during field measurements over a wide range of ambient temperature. The system can operate continuously for up to 8hrs on rechargeable batteries. The signal output from the charge loss corrector is compatible with most analog and digital spectroscopy amplifiers and multi channel analyzers. Using a detector measuring 11.2 by 9.1 by 2.13 mm3, we have recently been able to obtain the first wide-range plutonium gamma-ray isotopic analysis with other than a cryogenically cooled germanium spectrometer. The CdTe spectrometer is capable of measuring small plutonium reference samples in about one hour, covering the range from low to high burnup. The isotopic analysis software used to obtain these results was FRAM, Version 4 from LANL. The new spectrometer is expected to be useful for low-grade assay, as well as for some in-situ plutonium gamma-ray isotopics in lieu of cryogenically cooled Ge.

  2. Formation of Hot Nuclei with GeV {ital p} and {ital {pi}}{sup {minus}} Beams

    SciTech Connect

    Hsi, W.; Kwiatkowski, K.; Wang, G.; Bracken, D.S.; Cornell, E.; Ginger, D.S.; Viola, V.E.; Yoder, N.R.; Korteling, R.G.; Gimeno-Nogures, F.; Ramakrishnan, E.; Rowland, D.; Yennello, S.J.; Huang, M.J.; Lynch, W.G.; Tsang, M.B.; Xi, H.; Chu, Y.Y.; Gushue, S.; Remsberg, L.P.; Morley, K.B.; Breuer, H.

    1997-08-01

    4{pi} studies of multiple charged-particle emission in GeV {pi}{sup {minus}} - and proton-induced reactions on a Au target have been performed with the ISiS detector array. Multiplicity, charge, and angular distributions yield nearly identical results for both p and {pi}{sup {minus}} beams, suggesting an independence of hadron type in initiating the fast cascade and subsequent energy deposition in the struck nucleus. The excitation functions show little sensitivity to beam momentum, consistent with a saturation in deposition energy and the concept of limiting fragmentation. However, the intermediate mass fragment multiplicities and fragment charge distributions depend strongly on collision violence. {copyright} {ital 1997} {ital The American Physical Society}

  3. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) spectrometer design and performance

    NASA Technical Reports Server (NTRS)

    Macenka, Steven A.; Chrisp, Michael P.

    1987-01-01

    The development of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has been completed at JPL. This paper outlines the functional requirements of the spectrometer optics subsystem, and describes the spectrometer optical design. The optical subsystem performance is shown in terms of spectral modulation transfer functions, radial energy distributions, and system transmission at selected wavelengths for the four spectrometers. An outline of the spectrometer alignment is included.

  4. Nucleon Form Factors above 6 GeV

    DOE R&D Accomplishments Database

    Taylor, R. E.

    1967-09-01

    This report describes the results from a preliminary analysis of an elastic electron-proton scattering experiment... . We have measured cross sections for e-p scattering in the range of q{sup 2} from 0.7 to 25.0 (GeV/c){sup 2}, providing a large region of overlap with previous measurements. In this experiment we measure the cross section by observing electrons scattered from a beam passing through a liquid hydrogen target. The scattered particles are momentum analyzed by a magnetic spectrometer and identified as electrons in a total absorption shower counter. Data have been obtained with primary electron energies from 4.0 to 17.9 GeV and at scattering angles from 12.5 to 35.0 degrees. In general, only one measurement of a cross section has been made at each momentum transfer.

  5. Parity-violating DIS at 12 GeV

    SciTech Connect

    Souder, Paul

    2007-06-01

    The advent of the 12-GeV upgrade at JLab will present an excellent opportunity to study parity violation in deep inelastic scattering at high values of x. The physics issues in this domain include charge symmetry violation, quark-quark correlations in the nucleon, and tests of the Standard Model. This program will require a high-luminosity detector with high acceptance for scattering angles up to about 35°. A possible design for a solenoidal spectrometer that meets this requirement is suggested.

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

    SciTech Connect

    Hunka Deborah Elaine; Austin, Daniel E.

    2005-07-01

    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.

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

    SciTech Connect

    Hunka, Deborah E; Austin, Daniel

    2005-10-01

    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

  8. SiGe/Si heterojunction internal photoemission long-wavelength infrared detectors fabricated by molecular beam epitaxy

    NASA Technical Reports Server (NTRS)

    Lin, True-Lon; Ksendzov, A.; Dejewski, Suzan M.; Jones, Eric W.; Fathauer, Robert W.; Krabach, Timothy N.; Maserjian, Joseph

    1991-01-01

    A new SiGe/Si heterojunction internal photoemission (HIP) long-wavelength infrared (LWIR) detector has been fabricated by molecular beam epitaxy (MBE). The detection mechanism of the SiGe/Si HIP detector is infrared absorption in the degenerately doped p+-SiGe layer followed by internal photoemission of photoexcited holes over a heterojunction barrier. By adjusting the Ge concentration in the SiGe layer, and, consequently, the valence band offset between SiGe and Si, the cutoff wavelength of SiGe HIP detectors can be extended into the LWIR (8-17-micron) regime. Detectors were fabricated by growing p+-SiGe layers using MBE on patterned p-type Si substrates. The SiGe layers were boron-doped, with concentrations ranging from 10 to the 19th/cu cm to 4 x 10 to the 20th/cu cm. Infrared absorption of 5-25 percent in a 30-nm-thick p+-SiGe layer was measured in the 3-20-micron range using a Fourier transform infrared spectrometer. Quantum efficiencies of 3-5 percent have been obtained from test devices in the 8-12-micron range.

  9. 12 GeV detector technology at Jefferson Lab

    SciTech Connect

    Leckey, John P.; Collaboration: GlueX Collaboration

    2013-04-19

    The Thomas Jefferson National Accelerator Facility (JLab) is presently in the middle of an upgrade to increase the energy of its CW electron beam from 6 GeV to 12 GeV along with the addition of a fourth experimental hall. Driven both by necessity and availability, novel detectors and electronics modules have been used in the upgrade. One such sensor is the Silicon Photomultiplier (SiPM), specifically a Multi-Pixel Photon Counter (MPPC), which is an array of avalanche photodiode pixels operating in Geiger mode that are used to sense photons. The SiPMs replace conventional photomultiplier tubes and have several distinct advantages including the safe operation in a magnetic field and the lack of need for high voltage. Another key to 12 GeV success is advanced fast electronics. Jlab will use custom 250 MHz and 125 MHz 12-bit analog to digital converters (ADCs) and time to digital converters (TDCs) all of which take advantage of VME Switched Serial (VXS) bus with its GB/s high bandwidth readout capability. These new technologies will be used to readout drift chambers, calorimeters, spectrometers and other particle detectors at Jlab once the 12 GeV upgrade is complete. The largest experiment at Jlab utilizing these components is GlueX - an experiment in the newly constructed Hall D that will study the photoproduction of light mesons in the search for hybrid mesons. The performance of these components and their respective detectors will be presented.

  10. GRIS background reduction results using isotopically enriched Ge

    NASA Technical Reports Server (NTRS)

    Barthelmy, S. D.; Bartlett, L. M.; Gehrels, N.; Leventhal, M.; Teegarden, B. J.; Tueller, J.; Belyaev, S.; Lebedev, V.; Klapdor-Kleingrothaus, H. V.

    1994-01-01

    The Gamma Ray Imaging Spectrometer (GRIS) was flown twice from Alice Springs, Australia, in the spring of 1992 for a total of 32 hr at float altitude. One of the seven Ge detectors was isotopically enriched (greater than 97% Ge-70). This was the first time an enriched-Ge detector was used for astrophysical observations. Because of its thick anticoincidence shield, the GRIS instrument background is dominated by internal beta-decay in the energy range of 200-1000 keV. Half of the contribution in this beta-decay 'hump' is due to neutron-activated Ge-74. In this energy range, GRIS observed a factor of 2 reduction in the background in the enriched detector, as predicted. In future instruments (e.g., INTEGRAL), with thicker anticoincidence shields and smaller apertures, the background reduction will be even larger. Three strong instrumental background lines (54, 67, and 139 keV) are also eliminated. The elimination of the first two is particularly important for cylotron line observations.