National Library of Energy BETA

Sample records for alpha magnetic spectrometer

  1. The Gamma Ray Detection Capabilities of the Alpha Magnetic Spectrometer

    E-Print Network [OSTI]

    R. Battiston; M. Biasini; E. Fiandrini; J. Petrakis; M. H. Salamon

    1999-09-30

    The modeled performance of the Alpha Magnetic Spectrometer (AMS) as a high energy (0.3 to 100 GeV) gamma-ray detector is described, and its gamma ray astrophysics objectives are discussed.

  2. The 28th International Cosmic Ray Conference 1 The Alpha Magnetic Spectrometer on the International

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    The 28th International Cosmic Ray Conference 1 The Alpha Magnetic Spectrometer on the International", I.N.F.N Sez. Roma1, Roma, Italy Abstract The Alpha Magnetic Spectrometer (AMS) is a particle physics Academy Press, Inc. #12;2 Fig. 1. The Alpha Magnetic Spectrometer on the International Space Station. e

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

    E-Print Network [OSTI]

    Harrison, Stephen

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

  4. The Alpha Magnetic Spectrometer on the International Space Station

    E-Print Network [OSTI]

    Carmen Palomares

    2005-05-20

    The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to operate on the International Space Station (ISS). The aim of AMS is the direct detection of charged particles in the rigidity range from 0.5 GV to few TV to perform high statistics studies of cosmic rays in space and search for antimatter and dark matter. This will be possible because of the large geometrical acceptance, a very accurate energy determination and a very precise particle identification through redundant measurements of its energy, velocity and electric charge. AMS is scheduled to be placed on the ISS at the beginning of 2008 for a 3 year exposure.

  5. 2786 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 52, NO. 6, DECEMBER 2005 The Alpha Magnetic Spectrometer

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    , superconducting spectrom- eter. I. INTRODUCTION THE Alpha Magnetic Spectrometer (AMS) is a high-energy particle2786 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 52, NO. 6, DECEMBER 2005 The Alpha Magnetic Spectrometer on the International Space Station B. Borgia on behalf of AMS Collaboration Abstract--The Alpha

  6. Search for Antimatter in Space with the Alpha Magnetic Spectrometer

    E-Print Network [OSTI]

    Roberto Battiston

    1999-07-12

    The Alpha Magnetic Spectrometer (AMS) is a state of the art particle physics experiment for the extraterrestrial study of antimatter, matter and missing matter. AMS successfully completed the precursor STS91 Discovery flight (June 2nd-12th, 1998), completing 152 orbits at 52 degrees of latitude and about 400 km of height, collecting more than 100 million CR events. In this paper we report on the first flight experience and we present preliminary results on the search for nuclear antimatter. No antimatter nuclei with Z>=2 were detected. We obtain a model dependent upper limit on the anti-He /He flux 2, improving the results of previous published searches performed with stratospheric balloons.

  7. Physics Results From Alpha Magnetic Spectrometer 1998 Shuttle Flight

    E-Print Network [OSTI]

    Ming-Huey A. Huang

    2001-04-13

    The Alpha Magnetic Spectrometer (AMS) is a particle detector designed to detect antimatter. During the 10-day test flight on the space shuttle in June 1998, AMS detected $10^8$ events. Upon analysis, no antimatter was found and the antimatter limit was reduced to $1.1\\times10^{-6}$. The proton spectrum shows some differences with the cosmic ray flux used in atmospheric neutrino simulation. A large amount of protons, positrons, and electrons were found below the geomagnetic rigidity cutoff. The energy of these particles are as high as several GeV, one order of magnitude higher than any previously measured energy in radiation belts. These particles also exhibit many interesting features. This paper reviews the results in the four published papers of the AMS collaboration and provides explanation for some features of the albedo particles.

  8. Nuclear Instruments and Methods in Physics Research A 478 (2002) 119122 The Alpha Magnetic Spectrometer (AMS)

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    2002-01-01

    Nuclear Instruments and Methods in Physics Research A 478 (2002) 119­122 The Alpha Magnetic Spectrometer (AMS) J. Alcaraza , B. Alpatb , G. Ambrosic , H. Anderhubd , L. Aoe , A. Arefievf , P. Azzarelloc

  9. The Capabilities of the Alpha Magnetic Spectrometer as GeV Gamma-rays Detector

    E-Print Network [OSTI]

    R. Battiston

    1999-11-13

    The modeled performance of the Alpha Magnetic Spectrometer (AMS) as a high-energy (0.3 to 100 GeV) gamma-ray detector is described, and its gamma-ray astrophysics objectives are discussed.

  10. Cosmic-Ray Studies with an Alpha Magnetic Spectrometer (AMS Detector) on the International Space Station

    SciTech Connect (OSTI)

    Plyaskin, V.V. [Institute of Theoretical and Experimental Physics, Bol'shaya Cheremushkinskaya ul. 25, Moscow, 117259 (Russian Federation)

    2005-01-01

    A brief description of the physics research program implemented with an alpha magnetic spectrometer (AMS detector) by a large-scale international collaboration on board the International Space Station is presented. The features of the experimental facility under construction are given, along with some results obtained during the test flight of the prototype spectrometer on board a space shuttle.

  11. Abstract--The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to measure charged cosmic rays spectra

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    Abstract--The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to measure Alpha Magnetic Spectrometer (AMS) is a high energy particle physics experiment in space to be placed hundred GeV. AMS is a superconducting spectrometer with large acceptance, long duration (3 years

  12. Recent results from the Alpha Magnetic Spectrometer (AMS) on the STS-91

    E-Print Network [OSTI]

    R. Battiston

    2001-01-30

    The Alpha Magnetic Spectrometer (AMS) is a state of the art detector for the extraterrestrial study of matter, antimatter and missing matter. During the ten days long STS-91 precursor flight in may 1998 AMS collected nearly 100 millions of Cosmic Rays on Low Earth Orbit, measuring with high accuracy their composition. We present results on the flux of proton, electron, positron and helium particles in the rigidity region 0.1 to 200 GV . Analysis of the under cutoff spectra indicates the existence of a new type of belts containing high energy particles and characterized by a dominance of positrons versus electrons.

  13. Alpha Magnetic Spectrometer (AMS02) experiment on the International Space Station (ISS)

    E-Print Network [OSTI]

    Behcet Alpat

    2003-08-27

    The Alpha Magnetic Spectrometer experiment is realized in two phases. A precursor flight (STS-91) with a reduced experimental configuration (AMS01) has successfully flown on space shuttle Discovery in June 1998. The final version (AMS02) will be installed on the International Space Station (ISS) as an independent module in early 2006 for an operational period of three years. The main scientific objectives of AMS02 include the searches for the antimatter and dark matter in cosmic rays. In this work we will discuss the experimental details as well as the improved physics capabilities of AMS02 on ISS.

  14. Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    E-Print Network [OSTI]

    Aguilar, M; 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; 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; 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; Mańá, 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; 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; 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; Türko?lu, 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

    2014-01-01

    Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ?30??GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

  15. An indirect dark matter search with diffuse gamma rays from the Galactic Centre with the Alpha Magnetic Spectrometer

    E-Print Network [OSTI]

    A. Jacholkowska; G. Lamanna; E. Nuss; J. Bolmont; C. Adloff; J. Alcaraz; R. Battiston; P. Brun; W. J. Burger; V. Choutko; G. Coignet; A. Falvard; E. Flandrini; L. Girard; C. Goy; K. Jedamzik; R. Kossakowski; G. Moultaka; S. Natale; J. Pochon; M. Pohl; S. Rosier-Lees; M. Sapinski; I. Sevilla Noarbe; JP. Vialle

    2006-05-23

    The detection of non-baryonic dark matter through its gamma-ray annihilation in the centre of our galaxy has been studied. The gamma fluxes according to different models have been simulated and compared to those expected to be observed with the Alpha Magnetic Spectrometer (AMS), during a long-term mission on board of the International Space Station. Under the assumption that the dark matter halo is composed of the lightest, stable supersymmetric particle, the neutralino, the results of the simulations in the framework of mSUGRA models, show that with a cuspy dark matter halo or a clumpy halo, the annihilation gamma-ray signal would be detected by AMS. More optimistic perspectives are obtained with the Anomaly Mediated Supersymmetry Breaking (AMSB) model. The latter leads also to a cosmologically important 6Li abundance. Finally, the discovery potential for the massive Kaluza-Klein dark matter candidates has been evaluated and their detection looks feasible.

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

    E-Print Network [OSTI]

    Basil, A.

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

  17. MICE Spectrometer Magnet System Progress

    SciTech Connect (OSTI)

    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.

  18. Associated Particle Tagging (APT) in Magnetic Spectrometers

    SciTech Connect (OSTI)

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

    2012-10-16

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

  19. AMS - a magnetic spectrometer on the international space station

    E-Print Network [OSTI]

    Arruda, Luísa; Barăo, Fernando; Barreira, Gaspar; Borges, Joăo; Gonçalves, Patrícia; Pimenta, Mário

    2008-01-01

    The Alpha Magnetic Spectrometer (AMS) is a particle detector, designed to search for cosmic antimatter and dark matter and to study the elemental and isotopic composition of primary cosmic rays, that will be installed on the International Space Station (ISS) in 2008 to operate for at least three years. The detector will be equipped with a ring imaging Cherenkov detector (RICH) enabling measurements of particle electric charge and velocity with unprecedented accuracy. Physics prospects and test beam results are shortly presented.

  20. AMS - a magnetic spectrometer on the international space station

    E-Print Network [OSTI]

    Luísa Arruda; Rui Pereira; Fernando Barăo; Gaspar Barreira; Joăo Borges; Patrícia Gonçalves; Mário Pimenta

    2008-01-31

    The Alpha Magnetic Spectrometer (AMS) is a particle detector, designed to search for cosmic antimatter and dark matter and to study the elemental and isotopic composition of primary cosmic rays, that will be installed on the International Space Station (ISS) in 2008 to operate for at least three years. The detector will be equipped with a ring imaging Cherenkov detector (RICH) enabling measurements of particle electric charge and velocity with unprecedented accuracy. Physics prospects and test beam results are shortly presented.

  1. La missione AMS Alpha Magnetic Spectrometer

    E-Print Network [OSTI]

    Roma "La Sapienza", UniversitĂ  di

    . OF BUCHAREST RUSSIA I.K.I. ITEP KURCHATOV INST. MOSCOW STATE UNIV. SPAIN CIEMAT - MADRID I.A.C. CANARIAS

  2. Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...

    Office of Scientific and Technical Information (OSTI)

    Warburton, E. K. PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...

  3. Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...

    Office of Scientific and Technical Information (OSTI)

    English Subject: PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...

  4. Mu2e Calibration: Electron Spectrometer and Magnetic Fields

    E-Print Network [OSTI]

    Gollin, George

    ,c , George Gollina,1 , Tim Hea , Guangyong Koha , Matthew McHugha , Daniel Persheya,b a Department of Physics calculations, MATLAB numerical integration, equivalent magnetic charge distributions, and series approximations Contact person: George Gollin, g-gollin@illinois.edu, +1 (217) 333-4451. - 1 - #12;Spectrometer

  5. 30TH INTERNATIONAL COSMIC RAY CONFERENCE In-orbit performances of the magnetic spectrometer of PAMELA

    E-Print Network [OSTI]

    Morselli, Aldo

    of the spectrometer of PAMELA is generated by a permanent magnet composed of five identical modules put one on top microstrip sensors, which are placed inside the magnetic cavity of a permanent magnet. The apparatus is used30TH INTERNATIONAL COSMIC RAY CONFERENCE In-orbit performances of the magnetic spectrometer

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

    SciTech Connect (OSTI)

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

    2011-07-15

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

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

    E-Print Network [OSTI]

    Green, Michael A

    2011-01-01

    MICE Note 324 What Caused the Lead burn-out in SpectrometerThe magnet failed because a lead to coil M2 failed before itof the magnet when the lead failure occurred. The lead that

  8. Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets

    E-Print Network [OSTI]

    The PANDA Collaboration; W. Erni; I. Keshelashvili; B. Krusche; M. Steinacher; Y. Heng; Z. Liu; H. Liu; X. Shen; O. Wang; H. Xu; J. Becker; F. Feldbauer; F. -H. Heinsius; T. Held; H. Koch; B. Kopf; M. Pelizaeus; T. Schroeder; M. Steinke; U. Wiedner; J. Zhong; A. Bianconi; M. Bragadireanu; D. Pantea; A. Tudorache; V. Tudorache; M. De Napoli; F. Giacoppo; G. Raciti; E. Rapisarda; C. Sfienti; E. Bialkowski; A. Budzanowski; B. Czech; M. Kistryn; S. Kliczewski; A. Kozela; P. Kulessa; K. Pysz; W. Schaefer; R. Siudak; A. Szczurek; W. Czy. zycki; M. Domagala; M. Hawryluk; E. Lisowski; F. Lisowski; L. Wojnar; D. Gil; P. Hawranek; B. Kamys; St. Kistryn; K. Korcyl; W. Krzemien; A. Magiera; P. Moskal; Z. Rudy; P. Salabura; J. Smyrski; A. Wronska; M. Al-Turany; I. Augustin; H. Deppe; H. Flemming; J. Gerl; K. Goetzen; R. Hohler; D. Lehmann; B. Lewandowski; J. Luehning; F. Maas; D. Mishra; H. Orth; K. Peters; T. Saito; G. Schepers; C. J. Schmidt; L. Schmitt; C. Schwarz; B. Voss; P. Wieczorek; A. Wilms; K. -T. Brinkmann; H. Freiesleben; R. Jaekel; R. Kliemt; T. Wuerschig; H. -G. Zaunick; V. M. Abazov; G. Alexeev; A. Arefiev; V. I. Astakhov; M. Yu. Barabanov; B. V. Batyunya; Yu. I. Davydov; V. Kh. Dodokhov; A. A. Efremov; A. G. Fedunov; A. A. Feshchenko; A. S. Galoyan; S. Grigoryan; A. Karmokov; E. K. Koshurnikov; V. Ch. Kudaev; V. I. Lobanov; Yu. Yu. Lobanov; A. F. Makarov; L. V. Malinina; V. L. Malyshev; G. A. Mustafaev; A. Olshevski; M. A. . Pasyuk; E. A. Perevalova; A. A. Piskun; T. A. Pocheptsov; G. Pontecorvo; V. K. Rodionov; Yu. N. Rogov; R. A. Salmin; A. G. Samartsev; M. G. Sapozhnikov; A. Shabratova; G. S. Shabratova; A. N. Skachkova; N. B. Skachkov; E. A. Strokovsky; M. K. Suleimanov; R. Sh. Teshev; V. V. Tokmenin; V. V. Uzhinsky; A. S. Vodopianov; S. A. Zaporozhets; N. I. Zhuravlev; A. G. Zorin; D. Branford; K. Foehl; D. Glazier; D. Watts; P. Woods; W. Eyrich; A. Lehmann; A. Teufel; S. Dobbs; Z. Metreveli; K. Seth; B. Tann; A. Tomaradze; D. Bettoni; V. Carassiti; A. Cecchi; P. Dalpiaz; E. Fioravanti; I. Garzia; M. Negrini; M. Savri`e; G. Stancari; B. Dulach; P. Gianotti; C. Guaraldo; V. Lucherini; E. Pace; A. Bersani; M. Macri; M. Marinelli; R. F. Parodi; I. Brodski; W. Doering; P. Drexler; M. Dueren; Z. Gagyi-Palffy; A. Hayrapetyan; M. Kotulla; W. Kuehn; S. Lange; M. Liu; V. Metag; M. Nanova; R. Novotny; C. Salz; J. Schneider; P. Schoenmeier; R. Schubert; S. Spataro; H. Stenzel; C. Strackbein; M. Thiel; U. Thoering; S. Yang; T. Clarkson; E. Cowie; E. Downie; G. Hill; M. Hoek; D. Ireland; R. Kaiser; T. Keri; I. Lehmann; K. Livingston; S. Lumsden; D. MacGregor; B. McKinnon; M. Murray; D. Protopopescu; G. Rosner; B. Seitz; G. Yang; M. Babai; A. K. Biegun; A. Bubak; E. Guliyev; V. S. Jothi; M. Kavatsyuk; H. Loehner; J. Messchendorp; H. Smit; J. C. van der Weele; F. Garcia; D. -O. Riska; M. Buescher; R. Dosdall; R. Dzhygadlo; A. Gillitzer; D. Grunwald; V. Jha; G. Kemmerling; H. Kleines; A. Lehrach; R. Maier; M. Mertens; H. Ohm; D. Prasuhn; T. Randriamalala; J. Ritman; M. Roeder; T. Stockmanns; P. Wintz; P. Wuestner; J. Kisiel; S. Li; Z. Li; Z. Sun; H. Xu; S. Fissum; K. Hansen; L. Isaksson; M. Lundin; B. Schroeder; P. Achenbach; M. C. Mora Espi; J. Pochodzalla; S. Sanchez; A. Sanchez-Lorente; V. I. Dormenev; A. A. Fedorov; M. V. Korzhik; O. V. Missevitch; V. Balanutsa; V. Chernetsky; A. Demekhin; A. Dolgolenko; P. Fedorets; A. Gerasimov; V. Goryachev; A. Boukharov; O. Malyshev; I. Marishev; A. Semenov; C. Hoeppner; B. Ketzer; I. Konorov; A. Mann; S. Neubert; S. Paul; Q. Weitzel; A. Khoukaz; T. Rausmann; A. Taeschner; J. Wessels; R. Varma; E. Baldin; K. Kotov; S. Peleganchuk; Yu. Tikhonov; J. Boucher; T. Hennino; R. Kunne; S. Ong; J. Pouthas; B. Ramstein; P. Rosier; M. Sudol; J. Van de Wiele; T. Zerguerras; K. Dmowski; R. Korzeniewski; D. Przemyslaw; B. Slowinski; G. Boca; A. Braghieri; S. Costanza; A. Fontana; P. Genova; L. Lavezzi; P. Montagna; A. Rotondi; N. I. Belikov; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; D. A. Konstantinov; V. A. Kormilitsin; V. I. Kravtsov; Y. A. Matulenko; Y. M. Melnik; A. P. Meschanin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; S. B. Nurushev; A. V. Ryazantsev; P. A. Semenov; L. F. Soloviev; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; T. Baeck; B. Cederwall; C. Bargholtz; L. Geren; P. E. Tegner; S. Belostotski; G. Gavrilov; A. Itzotov; A. Kisselev; P. Kravchenko; S. Manaenkov; O. Miklukho; Y. Naryshkin; D. Veretennikov; V. Vikhrov; A. Zhadanov; L. Fava; D. Panzieri; D. Alberto; A. Amoroso; E. Botta; T. Bressani; S. Bufalino; M. P. Bussa; L. Busso; F. De Mori; M. Destefanis; L. Ferrero; A. Grasso; M. Greco; T. Kugathasan; M. Maggiora; S. Marcello; G. Serbanut; S. Sosio; R. Bertini; D. Calvo; S. Coli; P. De Remigis; A. Feliciello; A. Filippi; G. Giraudo; G. Mazza

    2009-07-01

    This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible modifications arising during this process.

  9. Magnetic interaction in oxygenated alpha Fe-phthalocyanines

    SciTech Connect (OSTI)

    Kuzmann, Ern?, E-mail: kuzmann@caesar.elte.hu; Homonnay, Zoltán; Horváth, Attila [Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, 1512 Budapest (Hungary); Pechousek, Jiri; Cuda, Jan; Machala, Libor; Zoppellaro, Giorgio; Zboril, Radek [Regional Centre of Advanced Technologies and Materials, Departments of Experimental Physics and Physical Chemistry, Faculty of Science Palacky University, 17. Listopadu 1192/12, 771 46 Olomouc (Czech Republic); Yin, Houping; Wei, Yen [Department of Chemistry, Drexel University, Philadelphia, PA 19104 (United States); Klencsár, Zoltán [Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, 1117 (Hungary); Kubuki, Shiro [Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachi-Oji, Tokyo 192-0397 (Japan); Nath, Amar [Department of Chemistry, University of North Carolina, Asheville, NC 28804 (United States)

    2014-10-27

    Alpha iron phthalocyanines (?-FePc) oxygenated at low temperatures were investigated with the help of {sup 57}Fe Mössbauer spectroscopy, magnetization measurements (SQUID) and X-ray diffractometry (XRD). Mössbauer spectroscopy revealed that upon oxygenation of ?-FePc, new species were formed which could be associated with Fe{sup III}Pc oxygen adducts. Unexpectedly, magnetically split spectrum of oxygenated ?-FePc was observed below 20 K. In-field Mössbauer spectra in a 5 T external magnetic field at 5K and magnetization measurements indicate antiferromagnetic coupling in oxygenated ?-FePc.

  10. The magnetic shielding for the neutron decay spectrometer aSPECT

    E-Print Network [OSTI]

    Gertrud Konrad; Fidel Ayala Guardia; Stefan Baeßler; Michael Borg; Ferenc Glück; Werner Heil; Stefan Hiebel; Raquel Munoz Horta; Yury Sobolev

    2014-05-05

    Many experiments in nuclear and neutron physics are confronted with the problem that they use a superconducting magnetic spectrometer which potentially affects other experiments by their stray magnetic field. The retardation spectrometer aSPECT consists, inter alia, of a superconducting magnet system that produces a strong longitudinal magnetic field of up to 6.2T. In order not to disturb other experiments in the vicinity of aSPECT, we had to develop a magnetic field return yoke for the magnet system. While the return yoke must reduce the stray magnetic field, the internal magnetic field and its homogeneity should not be affected. As in many cases, the magnetic shielding for aSPECT must manage with limited space. In addition, we must ensure that the additional magnetic forces on the magnet coils are not destructive. In order to determine the most suitable geometry for the magnetic shielding for aSPECT, we simulated a variety of possible geometries and combinations of shielding materials of non-linear permeability. The results of our simulations were checked through magnetic field measurements both with Hall and nuclear magnetic resonance probes. The experimental data are in good agreement with the simulated values: The mean deviation from the simulated exterior magnetic field is (-1.7+/-4.8)%. However, in the two critical regions, the internal magnetic field deviates by 0.2% respectively <1E-4 from the simulated values.

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

    DOE Patents [OSTI]

    Fan, N.Q.; Clarke, J.

    1993-10-19

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

  12. Detection of alpha radiation in a beta radiation field

    DOE Patents [OSTI]

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

    2001-01-01

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

  13. Design and commissioning of a high magnetic field muon spin relaxation spectrometer at the ISIS pulsed neutron and muon source

    SciTech Connect (OSTI)

    Lord, J. S.; McKenzie, I.; Baker, P. J.; Cottrell, S. P.; Giblin, S. R.; Hillier, A. D.; Holsman, B. H.; King, P. J. C.; Nightingale, J. B.; Pratt, F. L.; Rhodes, N. J.; Blundell, S. J.; Lancaster, T.; Good, J.; Mitchell, R.; Owczarkowski, M.; Poli, S.; Scheuermann, R.; Salman, Z.

    2011-07-15

    The high magnetic field (HiFi) muon instrument at the ISIS pulsed neutron and muon source is a state-of-the-art spectrometer designed to provide applied magnetic fields up to 5 T for muon studies of condensed matter and molecular systems. The spectrometer is optimised for time-differential muon spin relaxation studies at a pulsed muon source. We describe the challenges involved in its design and construction, detailing, in particular, the magnet and detector performance. Commissioning experiments have been conducted and the results are presented to demonstrate the scientific capabilities of the new instrument.

  14. The lead-glass electromagnetic calorimeters for the magnetic spectrometers in Hall C at Jefferson Lab

    E-Print Network [OSTI]

    H. Mkrtchyan; R. Carlini; V. Tadevosyan; J. Arrington; A. Asaturyan; M. E. Christy; D. Dutta; R. Ent; H. C. Fenker; D. Gaskell; T. Horn; M. K. Jones; C. E. Keppel; D. J. Mack; S. P. Malace; A. Mkrtchyan; M. I. Niculescu; J. Seely; V. Tvaskis; S. A. Wood; S. Zhamkochyan

    2012-04-28

    The electromagnetic calorimeters of the various magnetic spectrometers in Hall C at Jefferson Lab are presented. For the existing HMS and SOS spectrometers design considerations, relevant construction information, and comparisons of simulated and experimental results are included. The energy resolution of the HMS and SOS calorimeters is better than $\\sigma/E \\sim 6%/\\sqrt E $, and pion/electron ($\\pi/e$) separation of about 100:1 has been achieved in energy range 1 -- 5 GeV. Good agreement has been observed between the experimental and simulated energy resolutions, but simulations systematically exceed experimentally determined $\\pi^-$ suppression factors by close to a factor of two. For the SHMS spectrometer presently under construction details on the design and accompanying GEANT4 simulation efforts are given. The anticipated performance of the new calorimeter is predicted over the full momentum range of the SHMS. Good electron/hadron separation is anticipated by combining the energy deposited in an initial (preshower) calorimeter layer with the total energy deposited in the calorimeter.

  15. Measurement of the Internal Magnetic Field of Plasmas using an Alpha Particle Source

    SciTech Connect (OSTI)

    S.J. Zweben; D.S. Darrow; P.W. Ross; J.L. Lowrance; G. Renda

    2004-05-13

    The internal magnetic fields of plasmas can be measured under certain conditions from the integrated v x B deflection of MeV alpha particles emitted by a small radioactive source. This alpha source and large-area alpha particle detector would be located inside the vacuum vessel but outside the plasma. Alphas with a typical energy of 5.5 MeV (241Am) can reach the center of almost all laboratory plasmas and magnetic fusion devices, so this method can potentially determine the q(r) profile of tokamaks or STs. Orbit calculations, background evaluations, and conceptual designs for such a vxB (or ''AVB'') detector are described.

  16. An alpha scintillation spectrometer 

    E-Print Network [OSTI]

    Yates, Ralph Aaron

    1952-01-01

    scintiilation counters& and for this reason they will be of in- terest here, The amount of light produced by an ionirirg particle of a given energy varies considerably under apparently co& st ant conditions. &'<housi& the particle loses about the same.... Uranium 1'hick Uranium sources were tested to determine if any differences would exist between the oulse height distribution oi' thick Uranium and Thorium sources. Sources were prepared by placing small pieces of Uranium nitrate, UO2 (NO3)2 6H20, on a...

  17. First measurements of the absolute neutron spectrum using the Magnetic Recoil Spectrometer (MRS) at OMEGA

    SciTech Connect (OSTI)

    Frenje, J A; Casey, D T; Li, C K; Rygg, J R; Seguin, F H; Petrasso, R D; Glebov, V Y; Meyerhofer, D D; Sangster, T C; Hatchett, S; Haan, S; Cerjan, C; Landen, O; Moran, M; Song, P; Wilson, D C; Leeper, R J

    2008-05-12

    A new type of neutron spectrometer, called a Magnetic Recoil Spectrometer (MRS), has been built and implemented at the OMEGA laser facility [T. R. Boehly. D. L. Brown, R. S. Craxton et al., Opt. Commun. 133, 495 (1997)] for absolute measurements of the neutron spectrum in the range 6 to 30 MeV, from which fuel areal density ({rho}R), ion temperature (T{sub i}) and yield (Y{sub n}) can be determined. The results from the first MRS measurements of the absolute neutron spectrum are presented. In addition, measuring {rho}R at the National Ignition Facility (NIF) [G.H. Miller, E.I. Moses and C.R. Wuest, Nucl. Fusion 44, S228 (2004)] will be essential for assessing implosion performance during all stages of development from surrogate implosions to cryogenic fizzles and ignited implosions. To accomplish this, we are also developing an MRS for the NIF. As much of the R&D and instrument optimization of the MRS at OMEGA is directly applicable to the MRS at the NIF, a description of the MRS design on the NIF is discussed as well.

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

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

    Casey, D. T. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Frenje, J. A. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Gatu Johnson, M. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Seguin, F. H. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Li, C. K. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Petrasso, R. D. [MIT, Cambridge, MA (United States). Plasma Science and Fusion Center; Glebov, V. Yu. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Katz, J. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Magoon, J. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Meyerhofer, D. D. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Sangster, T. C. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Shoup, M. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Ulreich, J. [Univ. of Rochester, NY (United States). Lab. for Laser Energitics; Ashabranner, R. C. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Bionta, R. M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Carpenter, A. C. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Felker, B. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Khater, H. Y. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); LePape, S. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); MacKinnon, A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); McKernan, M. A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Moran, M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Rygg, J. R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Yeoman, M. F. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Zacharias, R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Leeper, R. J. [Sandia National Laboratories, Albuquerque, NM (United States); Fletcher, K. [State Univ. of New York at Geneseo, NY (United States); Farrell, M. [General Atomics, San Diego, CA (United States); Jasion, D. [General Atomics, San Diego, CA (United States); Kilkenny, J. [General Atomics, San Diego, CA (United States); Paguio, R. [General Atomics, San Diego, CA (United States)

    2013-01-01

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

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

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

    Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D.; Glebov, V. Yu.; Katz, J.; Magoon, J.; Meyerhofer, D. D.; et al

    2013-04-18

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

  20. Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

    SciTech Connect (OSTI)

    Cui, Z. Q.; Chen, Z. J.; Xie, X. F.; Peng, X. Y.; Hu, Z. M.; Du, T. F.; Ge, L. J.; Zhang, X.; Yuan, X.; Fan, T. S.; Chen, J. X.; Li, X. Q., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn; Zhang, G. H., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn [School of Physics, State Key Lab of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xia, Z. W. [Southwestern Institute of Physics, Chengdu 610225 (China); Hu, L. Q.; Zhong, G. Q.; Lin, S. Y.; Wan, B. N. [Institute of Plasma Physics, CAS, Hefei 230031 (China)

    2014-11-15

    The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G.

  1. Possibility of Testing the Light Dark Matter Hypothesis with the Alpha Magnetic Spectrometer

    SciTech Connect (OSTI)

    Hooper, Dan; Xue, Wei

    2013-01-01

    The spectrum and morphology of gamma-rays from the Galactic Center and the spectrum of synchrotron emission observed from the Milky Way's radio filaments have each been interpreted as possible signals of $\\sim$7-10 GeV dark matter particles annihilating in the Inner Galaxy. In dark matter models capable of producing these signals, the annihilations should also generate significant fluxes of $\\sim$7-10 GeV positrons which can lead to a distinctive bump-like feature in local cosmic ray positron spectrum. In this letter, we show that while such a feature would be difficult to detect with PAMELA, it would likely be identifiable by the currently operating AMS experiment. As no known astrophysical sources or mechanisms are likely to produce such a sharp feature, the observation of a positron bump at around 7-10 GeV would significantly strengthen the case for a dark matter interpretation of the reported gamma-ray and radio anomalies.

  2. Latest Results from the Alpha Magnetic Spectrometer on the International Space Station

    E-Print Network [OSTI]

    Martin Pohl

    2014-12-08

    I review latest results from AMS on electrons and positrons in primary cosmic rays in the GeV to TeV energy range. Separate fluxes for electrons and positrons as well as their sum are presented. Neither of the fluxes is compatible with a simple power law. New data on the fraction of positrons in the joint electron and positron flux are also presented, which extend the energy range of our previous observation and increase its precision. The new results show, for the first time, that above about 200 GeV the positron fraction no longer exhibits an increase with energy. The results confirm that a common new source of electrons and positrons exists.

  3. The Alpha Magnetic Spectrometer (AMS): search for antimatter and dark matter on the International Space Station

    E-Print Network [OSTI]

    R. Battiston

    1997-08-27

    The AMS is a state of the art detector for extraterrestrial study of antimatter, matter and missing matter. After a precursor flight on STS91 in May 1998, AMS will be installed on the International Space Station where it will operate for three years. In this paper the AMS experiment is described and is physics potential reviewed.

  4. Latest Results from the Alpha Magnetic Spectrometer on the International Space Station

    E-Print Network [OSTI]

    Pohl, Martin

    2014-01-01

    I review latest results from AMS on electrons and positrons in primary cosmic rays in the GeV to TeV energy range. Separate fluxes for electrons and positrons as well as their sum are presented. Neither of the fluxes is compatible with a simple power law. New data on the fraction of positrons in the joint electron and positron flux are also presented, which extend the energy range of our previous observation and increase its precision. The new results show, for the first time, that above about 200 GeV the positron fraction no longer exhibits an increase with energy. The results confirm that a common new source of electrons and positrons exists.

  5. REVIEW OF SCIENTIFIC INSTRUMENTS 82, 073301 (2011) Calibration of a Thomson parabola ion spectrometer and Fujifilm imaging

    E-Print Network [OSTI]

    2011-01-01

    spectrometer and Fujifilm imaging plate detectors for protons, deuterons, and alpha particles C. G. Freeman,1 G parabola ion spectrometer has been designed for use at the Multiterawatt (MTW) laser facility and magnetic fields to deflect particles of a given mass-to-charge ratio onto parabolic curves on the detector

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

    E-Print Network [OSTI]

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

  7. Developing improved nuclear magnetic resonance marginal oscillator spectrometers for advanced teaching laboratories 

    E-Print Network [OSTI]

    Willingham, Frank Phillip

    1988-01-01

    about one. The longitudinal relaxation time, Ti In a liquid macroscopic sample of nuclear dipoles at thermal equilibrium there is no preferred orientatiou of the dipoles vrhen there is no externally applied magnetic field. As discussed earlier, when... coherent precession of the magnetization about the magnetic field and introducing a "dephasing" effect among the dipoles. This de- phasing of the transverse component of M combined with the longitudinal relaxs. tion described above has been shown...

  8. Design study of magnetic environments for XYZ polarization analysis using 3He for the new thermal time of flight spectrometer TOPAS

    E-Print Network [OSTI]

    Zahir Salhi; Earl Babcock; Alexander Ioffe

    2012-01-25

    We present a finite element calculation of the magnetic field (MagNet software) taken with the newly proposed PASTIS Coil, which uses a wide-angle banana shaped 3He Neuton Spin Filter cell (NSF) to cover a large range of scattering angle. The goal of this insert is to enable XYZ polarization analysis to be installed on the future thermal time-of flight spectrometer TOPAS.

  9. High Energy Physics and Nuclear Physics Network Requirements

    E-Print Network [OSTI]

    Dart, Eli

    2014-01-01

    The AMS (Alpha Magnetic Spectrometer) is a satellite-basedProtocol Alpha Magnetic Spectrometer Argonne National

  10. Monolithic spectrometer

    DOE Patents [OSTI]

    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.

  11. Tight binding prediction of the {alpha}-Gd{sub 2}S{sub 3} magnetic structure

    SciTech Connect (OSTI)

    Roy, Lindsay E.; Hughbanks, Timothy

    2007-03-15

    Spin-dependent extended Hueckel tight binding (EHTB) calculations were carried out for the magnetic solid Gd{sub 2}S{sub 3} by considering 20 different variations in the ordering of the 4f {sup 7} moments. The tight-binding calculations are used to interpolate the band structure of a nonmagnetic congener (Y{sub 2}S{sub 3}) and the 4f/5d,6s exchange interactions are introduced as perturbations via the introduction of spin-dependent H{sub dd} and H{sub ss} parameters. The calculations predict that Gd{sub 2}S{sub 3} adopts an antiferromagnetic ordering of the 4f {sup 7} moments that is consistent with published neutron diffraction results. Our attempt to account for the calculated energies of the spin patterns using an Ising model was unsuccessful. - Graphical abstract: The spin-dependent EHTB method correctly predicts the magnetic structure of {alpha}-Gd{sub 2}S{sub 3} determined from neutron diffraction experiments.

  12. Correlation spectrometer

    DOE Patents [OSTI]

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

    2010-04-13

    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.

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

    SciTech Connect (OSTI)

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

    2010-11-08

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

  14. Development of multiwavelength-range fine-resolution spectrometer for hydrogen emissions and its application to large helical device periphery plasmas

    SciTech Connect (OSTI)

    Fujii, K.; Mizushiri, K.; Nishioka, T.; Shikama, T.; Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan); Iwamae, A. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka 311-0193 (Japan); Goto, M.; Morita, S. [National Institute for Fusion Science, Toki 509-5292 (Japan); Kado, S [Department of Nuclear Engineering and Management, School of Engineering, University of Tokyo, Tokyo 113-8656 (Japan); Sawada, K. [Department of Applied Physics, Faculty of Engineering, Shinshu University, Nagano 380-8553 (Japan)

    2010-03-15

    We developed a spectrometer specialized for simultaneous observation of the hydrogen Balmer-{alpha}, -{beta}, -{gamma} lines and the Fulcher-{alpha} v'=v''=2 rovibronic transition band. The spectrometer was optimized for the light input coupled by nine optical fibers having 400 {mu}m core diameters. The spectral resolutions were 0.02-0.03 nm for these wavelength ranges at the entrance slit width of 20 {mu}m. The polarization resolved spectra of these emissions from the peripheral region of large helical device (LHD) plasmas were measured simultaneously and showed the polarization dependence coming from the magnetic field in the LHD plasma.

  15. The Results of Tests of the MICE Spectrometer Solenoids

    SciTech Connect (OSTI)

    Green, Michael A.; Virostek, Steve P.

    2009-10-19

    The Muon Ionization Cooling Experiment (MICE) spectrometer solenoid magnets will be the first magnets to be installed within the MICE cooling channel. The spectrometer magnets are the largest magnets in both mass and surface area within the MICE ooling channel. Like all of the other magnets in MICE, the spectrometer solenoids are kept cold using 1.5 W (at 4.2 K) pulse tube coolers. The MICE spectrometer solenoid is quite possibly the largest magnet that has been cooled using small coolers. Two pectrometer magnets have been built and tested. This report discusses the results of current and cooler tests of both magnets.

  16. Cryostat design and analysis of the superconducting magnets for Jefferson Lab's 11-GEV/C super high momentum spectrometer

    SciTech Connect (OSTI)

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

    2010-04-01

    This paper describes the mechanical design and analysis of the cryostats for the two cos(2theta) quadrupoles and the cos(theta) dipole. All the magnets are currently being bid for commercial fabrication. The results of finite element analysis for the magnet cryostat helium vessels and outer vacuum chambers which investigate the mechanical integrity under maximum allowable internal working pressure, maximum allowable external working pressure, and cryogenic temperature are discussed. The allowable stress criterion is determined based on the allowable stress philosophy of the ASME codes. The computed cryogenic heat load of the magnets is compared with the allowable cryogenic consumption budget. The presented cool-down time of the magnets was studied under the conditions of a limited supply rate and a controlled temperature differential of 50 K in the magnets.

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) byMultidayAlumni >Scientific and TechnicalSpectrometer (AMS)

  18. Spectrometer gun

    DOE Patents [OSTI]

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

    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.

  19. Spectrometer gun

    DOE Patents [OSTI]

    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.

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

    SciTech Connect (OSTI)

    Eric Sun, Paul Brindza, Steven Lassister, Mike Fowler

    2012-07-01

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

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

    SciTech Connect (OSTI)

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

    2010-06-01

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

  2. Radon induced background processes in the KATRIN pre-spectrometer

    E-Print Network [OSTI]

    Fränkle, F M; Drexlin, G; Glück, F; Görhardt, S; Käfer, W; Mertens, S; Wandkowsky, N; Wolf, J

    2011-01-01

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next generation, model independent, large scale tritium beta-decay experiment to determine the effective electron anti-neutrino mass by investigating the kinematics of tritium beta-decay with a sensitivity of 200 meV/c2 using the MAC-E filter technique. In order to reach this sensitivity, a low background level of 0.01 counts per second (cps) is required. This paper describes how the decay of radon in a MAC-E filter generates background events, based on measurements performed at the KATRIN pre-spectrometer test setup. Radon (Rn) atoms, which emanate from materials inside the vacuum region of the KATRIN spectrometers, are able to penetrate deep into the magnetic flux tube so that the alpha-decay of Rn contributes to the background. Of particular importance are electrons emitted in processes accompanying the Rn alpha-decay, such as shake-off, internal conversion of excited levels in the Rn daughter atoms and Auger electrons. While low-energy electrons (<...

  3. Background due to stored electrons following nuclear decays in the KATRIN spectrometers and its impact on the neutrino mass sensitivity

    E-Print Network [OSTI]

    Mertens, S; Fraenkle, F M; Furse, D; Glueck, F; Goerhardt, S; Hoetzel, M; Kaefer, W; Leiber, B; Thuemmler, T; Wandkowsky, N; Wolf, J

    2012-01-01

    The KATRIN experiment is designed to measure the absolute neutrino mass scale with a sensitivity of 200 meV at 90% C.L. by high resolution tritium beta-spectroscopy. A low background level of 10 mHz at the beta-decay endpoint is required in order to achieve the design sensitivity. In this paper we discuss a novel background source arising from magnetically trapped keV electrons in electrostatic retarding spectrometers. The main sources of these electrons are alpha-decays of the radon isotopes (219,220)Rn as well as beta-decays of tritium in the volume of the spectrometers. We characterize the expected background signal by extensive MC simulations and investigate the impact on the KATRIN neutrino mass sensitivity. From these results we refine design parameters for the spectrometer vacuum system and propose active background reduction methods to meet the stringent design limits for the overall background rate.

  4. Mini ion trap mass spectrometer

    DOE Patents [OSTI]

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

    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.

  5. Mini ion trap mass spectrometer

    DOE Patents [OSTI]

    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.

  6. High resolution transmission grating spectrometer for edge toroidal rotation measurements of tokamak plasmas

    SciTech Connect (OSTI)

    Graf, A.; May, M.; Beiersdorfer, P.; Magee, E.; Lawrence, M.; Rice, J. [University of California, Davis, California 95616 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2004-10-01

    We present a high throughput (f/3) visible (3500-7000 A) Doppler spectrometer for toroidal rotation velocity measurements of the Alcator C-Mod tokamak plasma. The spectrometer has a temporal response of 1 ms and a rotation velocity sensitivity of {approx}10{sup 5} cm/s. This diagnostic will have a tangential view and map out the plasma rotation at several locations along the outer half of the minor radius (r/a>0.5). The plasma rotation will be determined from the Doppler shifted wavelengths of D{sub {alpha}} and magnetic and electric dipole transitions of highly ionized impurities in the plasma. The fast time resolution and high spectral resolving power are possible due to a 6 in. diam circular transmission grating that is capable of {lambda}/{delta}{lambda}{approx}15 500 at 5769 A in conjunction with a 50 {mu}m slit.

  7. High Resolution Transmission Grating Spectrometer for Edge Toroidal Rotation Measurements of Tokamak Plasmas

    SciTech Connect (OSTI)

    Graf, A; May, M; Beiersdorfer, P; Magee, E; Lawrence, M; Terry, J; Rice, J

    2004-04-29

    We present a high throughput (f/3) visible (3500 - 7000 Angstrom) Doppler spectrometer for toroidal rotation velocity measurements of the Alcator C-Mod tokamak plasma. The spectrometer has a temporal response of 1 ms and a rotation velocity sensitivity of {approx}10{sup 5} cm/s. This diagnostic will have a tangential view and map out the plasma rotation at several locations along the outer half of the minor radius (r/a > 0.5). The plasma rotation will be determined from the Doppler shifted wavelengths of D{sub alpha} and magnetic and electric dipole transitions of highly ionized impurities in the plasma. The fast time resolution and high spectral resolving power are possible due to a 6' diameter circular transmission grating that is capable of {lambda}/{Delta}{lambda} {approx} 15500 at 5769 Angstrom in conjunction with a 50 {micro}m slit.

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

    SciTech Connect (OSTI)

    Green, Michael A.; Wang, Li; Pan, Heng; Wu, Hong; Guo, Xinglong; Li, S. Y.; Zheng, S. X.; Virostek, Steve P.; DeMello, Allen J.; Li, Derun; Trillaud, Frederick; Zisman, Michael S.

    2010-05-30

    Tests of the spectrometer solenoids have taught us some important lessons. The spectrometer magnet lessons learned fall into two broad categories that involve the two stages of the coolers that are used to cool the magnets. On the first spectrometer magnet, the problems were centered on the connection of the cooler 2nd-stage to the magnet cold mass. On the first test of the second spectrometer magnet, the problems were centered on the cooler 1st-stage temperature and its effect on the operation of the HTS leads. The second time the second spectrometer magnet was tested; the cooling to the cold mass was still not adequate. The cryogenic designs of the MICE and MuCOOL coupling magnets are quite different, but the lessons learned from the tests of the spectrometer magnets have affected the design of the coupling magnets.

  9. Optical Calibration For Jefferson Lab HKS Spectrometer

    E-Print Network [OSTI]

    L. Yuan; L. Tang

    2005-11-04

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

  10. H\\alpha\\ Emission Variability in Active M Dwarfs

    E-Print Network [OSTI]

    Bell, Keaton J; Davenport, James R A; Hawley, Suzanne L; West, Andrew A; Rogel, Allen B

    2011-01-01

    We use ~12,000 spectra of ~3,500 magnetically active M0-M9 dwarfs from the Sloan Digital Sky Survey taken at 10-15 minute intervals, together with ~300 spectra of ~60 M0-M8 stars obtained hourly with the Hydra multi-object spectrometer, to probe H\\alpha\\ variability on timescales of minutes to weeks. With multiple observations for every star examined, we are able to characterize fluctuations in H\\alpha emission as a function of activity strength and spectral type. Stars with greater magnetic activity (as quantified by L_H\\alpha/L_bol) are found to be less variable at all spectral types. We attribute this result to the stronger level of persistent emission in the high activity stars, requiring a larger heating event in order to produce measurable variability. We also construct H\\alpha\\ structure functions to constrain the timescale of variability. The more active objects with lower variability exhibit a characteristic timescale longer than an hour, likely due to larger, longer lasting heating events, while the...

  11. Simulation of background from low-level tritium and radon emanation in the KATRIN spectrometers

    SciTech Connect (OSTI)

    Leiber, B. [Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany)] [Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Collaboration: KATRIN Collaboration

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a large-scale experiment for the model independent determination of the mass of electron anti-neutrinos with a sensitivity of 200 meV/c{sup 2}. It investigates the kinematics of electrons from tritium beta decay close to the endpoint of the energy spectrum at 18.6 keV. To achieve a good signal to background ratio at the endpoint, a low background rate below 10{sup ?2} counts per second is required. The KATRIN setup thus consists of a high luminosity windowless gaseous tritium source (WGTS), a magnetic electron transport system with differential and cryogenic pumping for tritium retention, and electro-static retarding spectrometers (pre-spectrometer and main spectrometer) for energy analysis, followed by a segmented detector system for counting transmitted beta-electrons. A major source of background comes from magnetically trapped electrons in the main spectrometer (vacuum vessel: 1240 m{sup 3}, 10{sup ?11} mbar) produced by nuclear decays in the magnetic flux tube of the spectrometer. Major contributions are expected from short-lived radon isotopes and tritium. Primary electrons, originating from these decays, can be trapped for hours, until having lost almost all their energy through inelastic scattering on residual gas particles. Depending on the initial energy of the primary electron, up to hundreds of low energetic secondary electrons can be produced. Leaving the spectrometer, these electrons will contribute to the background rate. This contribution describes results from simulations for the various background sources. Decays of {sup 219}Rn, emanating from the main vacuum pump, and tritium from the WGTS that reaches the spectrometers are expected to account for most of the background. As a result of the radon alpha decay, electrons are emitted through various processes, such as shake-off, internal conversion and the Auger deexcitations. The corresponding simulations were done using the KASSIOPEIA framework, which has been developed for the KATRIN experiment for low-energy electron tracking, field calculation and detector simulation. The results of the simulations have been used to optimize the design parameters of the vacuum system with regard to radon emanation and tritium pumping, in order to reach the stringent requirements of the neutrino mass measurement.

  12. Forward fitting of experimental data from a NE213 neutron detector installed with the magnetic proton recoil upgraded spectrometer at JET

    SciTech Connect (OSTI)

    Binda, F. Ericsson, G.; Eriksson, J.; Hellesen, C.; Conroy, S.; Sundén, E. Andersson; Collaboration: JET-EFDA Team

    2014-11-15

    In this paper, we present the results obtained from the data analysis of neutron spectra measured with a NE213 liquid scintillator at JET. We calculated the neutron response matrix of the instrument combining MCNPX simulations, a generic proton light output function measured with another detector and the fit of data from ohmic pulses. For the analysis, we selected a set of pulses with neutral beam injection heating (NBI) only and we applied a forward fitting procedure of modeled spectral components to extract the fraction of thermal neutron emission. The results showed the same trend of the ones obtained with the dedicated spectrometer TOFOR, even though the values from the NE213 analysis were systematically higher. This discrepancy is probably due to the different lines of sight of the two spectrometers (tangential for the NE213, vertical for TOFOR). The uncertainties on the thermal fraction estimates were from 4 to 7 times higher than the ones from the TOFOR analysis.

  13. Neutron spectrometer for fast nuclear reactors

    E-Print Network [OSTI]

    M. Osipenko; M. Ripani; G. Ricco; B. Caiffi; F. Pompili; M. Pillon; M. Angelone; G. Verona-Rinati; R. Cardarelli; G. Mila; S. Argiro

    2015-05-25

    In this paper we describe the development and first tests of a neutron spectrometer designed for high flux environments, such as the ones found in fast nuclear reactors. The spectrometer is based on the conversion of neutrons impinging on $^6$Li into $\\alpha$ and $t$ whose total energy comprises the initial neutron energy and the reaction $Q$-value. The $^6$LiF layer is sandwiched between two CVD diamond detectors, which measure the two reaction products in coincidence. The spectrometer was calibrated at two neutron energies in well known thermal and 3 MeV neutron fluxes. The measured neutron detection efficiency varies from 4.2$\\times 10^{-4}$ to 3.5$\\times 10^{-8}$ for thermal and 3 MeV neutrons, respectively. These values are in agreement with Geant4 simulations and close to simple estimates based on the knowledge of the $^6$Li(n,$\\alpha$)$t$ cross section. The energy resolution of the spectrometer was found to be better than 100 keV when using 5 m cables between the detector and the preamplifiers.

  14. Neutron spectrometer for fast nuclear reactors

    E-Print Network [OSTI]

    Osipenko, M; Ricco, G; Caiffi, B; Pompili, F; Pillon, M; Angelone, M; Verona-Rinati, G; Cardarelli, R; Mila, G; Argiro, S

    2015-01-01

    In this paper we describe the development and first tests of a neutron spectrometer designed for high flux environments, such as the ones found in fast nuclear reactors. The spectrometer is based on the conversion of neutrons impinging on $^6$Li into $\\alpha$ and $t$ whose total energy comprises the initial neutron energy and the reaction $Q$-value. The $^6$LiF layer is sandwiched between two CVD diamond detectors, which measure the two reaction products in coincidence. The spectrometer was calibrated at two neutron energies in well known thermal and 3 MeV neutron fluxes. The measured neutron detection efficiency varies from 4.2$\\times 10^{-4}$ to 3.5$\\times 10^{-8}$ for thermal and 3 MeV neutrons, respectively. These values are in agreement with Geant4 simulations and close to simple estimates based on the knowledge of the $^6$Li(n,$\\alpha$)$t$ cross section. The energy resolution of the spectrometer was found to be better than 100 keV when using 5 m cables between the detector and the preamplifiers.

  15. Confirming HD 23478 as a new magnetic B star hosting an H$\\alpha$-bright centrifugal magnetosphere

    E-Print Network [OSTI]

    Sikora, James; Bohlender, David; Neiner, Coralie; Oksala, Mary; Shultz, Matt; Cohen, David; ud-Doula, Asif; Grunhut, Jason; Monin, Dmitry; Owocki, Stan; Petit, Véronique; Rivinius, Thomas; Townsend, Richard

    2015-01-01

    In this paper we report 23 magnetic field measurements of the B3IV star HD 23478: 12 obtained from high resolution Stokes $V$ spectra using the ESPaDOnS (CFHT) and Narval (TBL) spectropolarimeters, and 11 from medium resolution Stokes $V$ spectra obtained with the DimaPol spectropolarimeter (DAO). HD 23478 was one of two rapidly rotating stars identified as potential "centrifugal magnetosphere" hosts based on IR observations from the Apache Point Observatory Galactic Evolution Experiment survey. We derive basic physical properties of this star including its mass ($M=6.1^{+0.8}_{-0.7}\\,M_\\odot$), effective temperature ($T_{\\rm eff}=20\\pm2\\,$kK), radius ($R=2.7^{+1.6}_{-0.9}\\,R_\\odot$), and age ($\\tau_{\\rm age}=3^{+37}_{-1}\\,$Myr). We repeatedly detect weakly-variable Zeeman signatures in metal, He and H lines in all our observations corresponding to a longitudinal magnetic field of $\\langle B_z\\rangle\\approx-2.0\\,$kG. The rotational period is inferred from Hipparcos photometry ($P_{\\rm rot}=1.0498(4)\\,$d). Und...

  16. Alpha Particle Diagnostic

    SciTech Connect (OSTI)

    Fisher, Ray, K.

    2009-05-13

    The study of burning plasmas is the next frontier in fusion energy research, and will be a major objective of the U.S. fusion program through U.S. collaboration with our international partners on the ITER Project. For DT magnetic fusion to be useful for energy production, it is essential that the energetic alpha particles produced by the fusion reactions be confined long enough to deposit a significant fraction of their initial ~3.5 MeV energy in the plasma before they are lost. Development of diagnostics to study the behavior of energetic confined alpha particles is a very important if not essential part of burning plasma research. Despite the clear need for these measurements, development of diagnostics to study confined the fast confined alphas to date has proven extremely difficult, and the available techniques remain for the most part unproven and with significant uncertainties. Research under this grant had the goal of developing diagnostics of fast confined alphas, primarily based on measurements of the neutron and ion tails resulting from alpha particle knock-on collisions with the plasma deuterium and tritium fuel ions. One of the strengths of this approach is the ability to measure the alphas in the hot plasma core where the interesting ignition physics will occur.

  17. ELECTRONICS UPGRADE OF HIGH RESOLUTION MASS SPECTROMETERS

    SciTech Connect (OSTI)

    Mcintosh, J; Joe Cordaro, J

    2008-03-10

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

  18. Flows and Non-thermal Velocities in Solar Active Regions Observed with the Extreme-ultraviolet Imaging Spectrometer on Hinode: A Tracer of Active Region Sources of Heliospheric Magnetic Fields?

    E-Print Network [OSTI]

    G. A. Doschek; H. P. Warren; J. T. Mariska; K. Muglach; J. L. Culhane; H. Hara; T Watanabe

    2008-07-17

    From Doppler velocity maps of active regions constructed from spectra obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft we observe large areas of outflow (20-50 km/s) that can persist for at least a day. These outflows occur in areas of active regions that are faint in coronal spectral lines formed at typical quiet Sun and active region temperatures. The outflows are positively correlated with non-thermal velocities in coronal plasmas. The bulk mass motions and non-thermal velocities are derived from spectral line centroids and line widths, mostly from a strong line of Fe XII at 195.12 Angstroms. The electron temperature of the outflow regions estimated from an Fe XIII to Fe XII line intensity ratio is about 1.2-1.4 MK. The electron density of the outflow regions derived from a density sensitive intensity ratio of Fe XII lines is rather low for an active region. Most regions average around 7E10+8 cm(-3), but there are variations on pixel spatial scales of about a factor of 4. We discuss results in detail for two active regions observed by EIS. Images of active regions in line intensity, line width, and line centroid are obtained by rastering the regions. We also discuss data from the active regions obtained from other orbiting spacecraft that support the conclusions obtained from analysis of the EIS spectra. The locations of the flows in the active regions with respect to the longitudinal photospheric magnetic fields suggest that these regions might be tracers of long loops and/or open magnetic fields that extend into the heliosphere, and thus the flows could possibly contribute significantly to the solar wind.

  19. Fabrication, Testing and Modeling of the MICE Superconducting Spectrometer Solenoids

    SciTech Connect (OSTI)

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

    2010-05-16

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

  20. Interface for liquid chromatograph-mass spectrometer

    DOE Patents [OSTI]

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

    1989-09-19

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

  1. Interface for liquid chromatograph-mass spectrometer

    DOE Patents [OSTI]

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

    1989-01-01

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

  2. What Happened with Spectrometer Magnet 2B

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01

    nitrogen in the tank attached to the shield. Table 8 shows aone. A nitrogen tank was attached to the shield to pre-coolof the shield, the temperature of the nitrogen tank should

  3. Neutron range spectrometer

    DOE Patents [OSTI]

    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.

  4. Progress on the Design and Fabircation of the MICE SpectrometerSolenoids

    SciTech Connect (OSTI)

    Virostek, S.P.; Green, M.A.; Lia, D.; Sizman, M.S.

    2007-06-20

    The Muon Ionization Cooling Experiment (MICE) willdemonstrate ionization cooling in a short section of a realistic coolingchannel using a muon beam at Rutherford Appleton Laboratory (RAL) in theUK. A five-coil, superconducting spectrometer solenoid magnet at each endof the cooling channel will provide a 4 T uniform field region for thescintillating fiber tracker within the magnet bore tubes. The trackermodules are used to measure the muon beam emittance as it enters andexits the cooling channel. The cold mass for the 400 mm warm bore magnetconsists of two sections: a three-coil spectrometer magnet and a two-coilmatching section that matches the uniform field of the solenoid into theMICE cooling channel. The spectrometer solenoid detailed designandanalysis has been completed, and the fabrication of the magnets is wellunder way. The primary features of the spectrometer solenoid magnet andmechanical designs are presented along with a summary of key fabricationissues and photos of the construction.

  5. Resonant ultrasound spectrometer

    DOE Patents [OSTI]

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

    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.

  6. Magnetic Resonance Facility (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-03-01

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

  7. An all-cryogenic THz transmission spectrometer P. J. Burkea)

    E-Print Network [OSTI]

    Eisenstein, Jim

    with an electrical current serves as a magnetic-field tunable source. The spectrometer is demonstrated at 4.2 K gas laser which couples optically to a cold sample from room temperature. The disadvantage, this technique can be car- ried out. One must construct a set of filters with the desired pass functions from

  8. Photo ion spectrometer

    DOE Patents [OSTI]

    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.

  9. Photo ion spectrometer

    DOE Patents [OSTI]

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

    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.

  10. Design Criteria Document Hybrid Spectrometer

    E-Print Network [OSTI]

    Johnson, Peter D.

    Design Criteria Document for the Hybrid Spectrometer (HYSPEC) SNS SING14B-00-DC0001-R00 Date: 15 contract DE-AC05-00OR22725 #12;DESIGN CRITERIA DOCUMENT FOR THE HYBRID SPECTROMETER (HYSPEC) August 2005 or reflect those of the United States government or any agency thereof. #12;SING14B-00-DC0001-R00 DESIGN

  11. Design Criteria Document Hybrid Spectrometer

    E-Print Network [OSTI]

    Johnson, Peter D.

    Design Criteria Document for the Hybrid Spectrometer (HYSPEC) SNS SING14B-00-DC0001-R01 Date: 1 contract DE-AC05-00OR22725 #12;DESIGN CRITERIA DOCUMENT FOR THE HYBRID SPECTROMETER (HYSPEC) Mark Hagen or reflect those of the United States government or any agency thereof. #12;SING14B-00-DC0001-R01 DESIGN

  12. Validation of a model for Radon-induced background processes in electrostatic spectrometers

    E-Print Network [OSTI]

    Wandkowsky, N; Fränkle, F M; Glück, F; Groh, S; Mertens, S

    2013-01-01

    The Karlsruhe Tritium Neutrino (KATRIN) experiment investigating tritium beta-decay close to the endpoint with unprecedented precision has stringent requirements on the background level of less than 10^(-2) counts per second. Electron emission during the alpha-decay of Rn-219 and Rn-220 atoms in the electrostatic spectrometers of KATRIN is a serious source of background exceeding this limit. In this paper we compare extensive simulations of Rn-induced background to specific measurements with the KATRIN pre-spectrometer to fully characterize the observed Rn-background rates and signatures and determine generic Rn emanation rates from the pre-spectrometer bulk material and its vacuum components.

  13. Alpha Radiation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TA I N P A T TSorbentsAllosteric ModulationAlphaBasics

  14. NUCLEAR DECAY SCHEMES IN THE ACTINIUM FAMILY

    E-Print Network [OSTI]

    Pilger Jr, Richard C.

    2010-01-01

    magnetic alpha-particle and electron high-resolution spectrographs and scintillation gamma-ray spectrometers,

  15. Photo ion spectrometer

    DOE Patents [OSTI]

    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.

  16. Neutron range spectrometer

    DOE Patents [OSTI]

    Manglos, Stephen H. (East Syracuse, NY)

    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.

  17. Aerosol mobility size spectrometer

    DOE Patents [OSTI]

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

    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.

  18. Spin dynamics of charge carriers in the process of their localization in {alpha}'-(BEDT-TTF){sub 2}IBr{sub 2} single crystals

    SciTech Connect (OSTI)

    Morgunov, R. B., E-mail: morgunov2005@yandex.ru; Dmitriev, A. I.; Chernen'kaya, A. S. [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation); Yakushi, K. [Graduate University for Advanced Studies (Japan); Yamamoto, K. [Institute for Molecular Science (Japan); Tanimoto, Y. [Osaka-Ohtani University, Faculty of Pharmacy (Japan)

    2010-11-15

    Sharp changes in the integral intensity and linewidth of the ESR spectrum that accompany the localization of the charge carriers have been revealed in {alpha}'-(BEDT-TTF){sub 2}IBr{sub 2} crystals. It has been found that the types of localization in two compounds under investigation are different: charge carriers in {beta}''-(BEDT-TTF){sub 4}NH{sub 4}[Cr(C{sub 2}O{sub 4}){sub 3}] are localized on irregular defects of the crystal lattice, whereas charge carriers in {alpha}'-(BEDT-TTF){sub 2}IBr{sub 2} are localized at the regular positions of the unit cell. The exchange narrowing of the ESR line and a sharp decrease in the dc and ac magnetic susceptibilities are observed in {alpha}'-(BEDT-TTF){sub 2}IBr{sub 2} at low temperatures T < 50 K. The dc and ac magnetic susceptibilities observed in {alpha}'-(BEDT-TTF){sub 2}IBr{sub 2} at high temperatures T > 50 K differ from each other, because the thermally activated hopping frequency of the charge carriers is higher than the frequency of the measuring UHF field of an ESR spectrometer.

  19. 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

    E-Print Network [OSTI]

    Accardo, L; 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; Mańá, 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; Türko?lu, 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

    2014-01-01

    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.

  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

    E-Print Network [OSTI]

    Aguilar, M; 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; Mańá, 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; Türko?lu, 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

    2014-01-01

    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 ?=?3.170±0.008(stat+syst)±0.008(energy?scale).

  1. CERN celebrated the first year in space for the Alpha Magnetic Spectrometer (AMS) with a visit from the crew of the shuttle mission, STS-134, who successfully delivered AMS to the International Space Station (ISS) last year.

    E-Print Network [OSTI]

    Laurent Egli

    2012-01-01

    During the celebrations at CERN, the astronauts unveiled a commemorative plaque on the lawn outside the POCC to mark the occasion and later gave a public lecture at CERN. Picture 28 : STS-134 astronauts (left to right) Andrew Feustel, Gregory Chamitoff, Gregory Johnson, Michael Fincke and Mark Kelly in the AMS Payload Operations Centre at CERN.

  2. Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

    E-Print Network [OSTI]

    Aguilar, M.

    A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is ...

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

    E-Print Network [OSTI]

    Aguilar, M.

    We present a measurement of the cosmic ray (e[superscript +] + e[superscript -]) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e[superscript +] + e[superscript -]) events collected by AMS. The ...

  4. 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 Public Access Gateway for Energy & Science Beta (PAGES Beta)

    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 ?= -3.170 ± 0.008(stat+syst) ± 0.008(energy scale).

  5. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

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

    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.

  6. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

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

    1995-12-19

    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.

  7. Grating spectrometer system for beam emission spectroscopy diagnostics using high-energy negative-ion-based neutral beam injection on LHD

    SciTech Connect (OSTI)

    Kado, S. [School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Oishi, T. [Graduate School/School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yoshinuma, M.; Ida, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

    2010-10-15

    A beam emission spectroscopy (BES) system was developed for density gradient and fluctuation diagnostics in the Large Helical Device (LHD). In order to cover the large Doppler shift of the H{alpha} beam emission because of the high-energy negative-ion-based neutral beam atom (acceleration voltage V{sub acc}=90-170 kV) and the large motional Stark splitting due to the large vxB field (magnetic field B=3.0 T), a grating spectrometer was used instead of a conventional interference filter system. The reciprocal linear dispersion is about 2 nm/mm, which is sufficient to cover the motional Stark effect spectra using an optical fiber with a diameter of 1 mm.

  8. Polarization resolved H{sub {alpha}} spectra from the large helical device: Emission location, temperature, and inward flux of neutral hydrogen

    SciTech Connect (OSTI)

    Iwamae, Atsushi; Hayakawa, Masayuki; Atake, Makoto; Fujimoto, Takashi; Goto, Motoshi; Morita, Shigeru [Department of Engineering Physics and Mechanics, Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan); National Institute for Fusion Science, Toki 509-5292 (Japan)

    2005-04-15

    Spectral profiles of the H{sub {alpha}} line emitted from the large helical device plasma [O. Motojima et al., Phys. Plasmas 6, 1843 (1999)] have been measured with polarization-separation optics and a high-resolution spectrometer. Besides the underlying high-temperature component, which probably arises from charge-exchange recombination, the profiles are interpreted as superpositions of Zeeman profiles for two different magnetic field strengths. The emission locations are thus identified on the magnetic field map; the emissions are localized in the inner and outer regions just outside the ergodic layer, and each field-strength contribution to the overall Zeeman profile represents two radiator temperatures, and inward atom flow velocities in the range of (1-7)x10{sup 3} m/s.

  9. Ab initio alpha-alpha scattering

    E-Print Network [OSTI]

    Serdar Elhatisari; Dean Lee; Gautam Rupak; Evgeny Epelbaum; Hermann Krebs; Timo A. Lähde; Thomas Luu; Ulf-G. Meißner

    2015-06-11

    Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.

  10. Ab initio alpha-alpha scattering

    E-Print Network [OSTI]

    Elhatisari, Serdar; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-01-01

    Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.

  11. Time of flight mass spectrometer

    DOE Patents [OSTI]

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

    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.

  12. MEMS-based Speckle Spectrometer

    E-Print Network [OSTI]

    A. I. Sheinis; L. Nigra; M. Q. Kuhlen

    2006-06-07

    We describe a new concept for a MEMS-based active spatial filter for astronomical spectroscopy. The goal of this device is to allow the use of a diffraction-limited spectrometer on a seeing limited observation at improved throughput over a comparable seeing-limited spectrometer, thus reducing the size and cost of the spectrometer by a factor proportional to r0/D (For the case of a 10 meter telescope this size reduction will be approximately a factor of 25 to 50). We use a fiber-based integral field unit (IFU) that incorporates an active MEMS mirror array to feed an astronomical spectrograph. A fast camera is used in parallel to sense speckle images at a spatial resolution of lambda/D and at a temporal frequency greater than that of atmospheric fluctuations. The MEMS mirror-array is used as an active shutter to feed speckle images above a preset intensity threshold to the spectrometer, thereby increasing the signal-to-noise ratio (SNR) of the spectrogram. Preliminary calculations suggests an SNR improvement of a factor of about 1.4. Computer simulations have shown an SNR improvement of 1.1, but have not yet fully explored the parameter space.

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

    SciTech Connect (OSTI)

    Chen, Hui E-mail: bitter@pppl.gov; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P.; Bitter, M. E-mail: bitter@pppl.gov; Hill, K. W.; Kerr, S.

    2014-11-15

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

  14. Progress on the Fabrication and Testing of the MICE Spectrometer Solenoids

    SciTech Connect (OSTI)

    Virostek, Steve; Green, M.A.; Li, Derun; Zisman, Michael

    2009-05-19

    The Muon Ionization Cooling Experiment (MICE) is an international collaboration that will demonstrate ionization cooling in a section of a realistic cooling channel using a muon beam at Rutherford Appleton Laboratory (RAL) in the UK. At each end of the cooling channel a spectrometer solenoid magnet consisting of five superconducting coils will provide a 4 tesla uniform field region. The scintillating fiber tracker within the magnet bore will measure the muon beam emittance as it enters and exits the cooling channel. The 400 mm diameter warm bore, 3 meter long magnets incorporate a cold mass consisting of two coil sections wound on a single aluminum mandrel: a three-coil spectrometer magnet and a two-coil section that matches the solenoid uniform field into the MICE cooling channel. The fabrication of the first of two spectrometer solenoids has been completed, and preliminary testing of the magnet is nearly complete. The key design features of the spectrometer solenoid magnets are presented along with a summary of the progress on the training and testing of the first magnet.

  15. A short working distance multiple crystal x-ray spectrometer

    SciTech Connect (OSTI)

    Dickinson, B.; Seidler, G. T.; Webb, Z. W.; Bradley, J. A.; Nagle, K. P. [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Heald, S. M. [Advanced Photon Source, Argonne National Laboratories, Argonne, Illinois 60439 (United States); Gordon, R. A. [Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); Chou, I. M. [U.S. Geological Survey, Reston, Virginia 20192 (United States)

    2008-12-15

    For x-ray spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed {approx}1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal x-ray spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K{beta} x-ray emission and resonant inelastic x-ray scattering for MnO, and also for measurements of the x-ray absorption near-edge structure for Dy metal using L{alpha}{sub 2} partial-fluorescence yield detection. We discuss future applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution x-ray emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary.

  16. On-Chip Random Spectrometer

    E-Print Network [OSTI]

    Redding, Brandon; Sarma, Raktim

    2013-01-01

    Light scattering in disordered media has been studied extensively due to its prevalence in natural and artificial systems [1]. In the field of photonics most of the research has focused on understanding and mitigating the effects of scattering, which are often detrimental. For certain applications, however, intentionally introducing disorder can actually improve the device performance, e.g., in photovoltaics optical scattering improves the efficiency of light harvesting [2-5]. Here, we utilize multiple scattering in a random photonic structure to build a compact on-chip spectrometer. The probe signal diffuses through a scattering medium generating wavelength-dependent speckle patterns which can be used to recover the input spectrum after calibration. Multiple scattering increases the optical pathlength by folding the paths in a confined geometry, enhancing the spectral decorrelation of speckle patterns and thus increasing the spectral resolution. By designing and fabricating the spectrometer on a silicon wafe...

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

    SciTech Connect (OSTI)

    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-of-flightTOFtime-of-flight4

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

    SciTech Connect (OSTI)

    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.

  19. Compact mass spectrometer for plasma discharge ion analysis

    DOE Patents [OSTI]

    Tuszewski, Michel G. (Los Alamos, NM)

    1997-01-01

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

  20. Compact mass spectrometer for plasma discharge ion analysis

    DOE Patents [OSTI]

    Tuszewski, M.G.

    1997-07-22

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

  1. Importance of magnetic helicity in dynamos

    E-Print Network [OSTI]

    A. Brandenburg

    2004-12-15

    Magnetic helicity is nearly conserved and its evolution equation provides a dynamical feedback on the alpha effect that is distinct from the conventional algebraic alpha quenching. The seriousness of this dynamical alpha quenching is particularly evident in the case of closed or periodic boxes. The explicit connection with catastrophic alpha quenching is reviewed and the alleviating effects of magnetic and current helicity fluxes are discussed.

  2. Portable neutron spectrometer and dosimeter

    DOE Patents [OSTI]

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

    1985-01-01

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

  3. Compact reflective imaging spectrometer utilizing immersed gratings

    DOE Patents [OSTI]

    Chrisp, Michael P. (Danville, CA)

    2006-05-09

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

  4. Alpha channeling in rotating plasma with stationary waves Abraham J. Fetterman and Nathaniel J. Fisch

    E-Print Network [OSTI]

    particle energy. Alpha channeling uses radiofrequency waves to remove alpha particles collisionlessly at low energy. It is shown that stationary magnetic fields with high n can be used for this purpose, and simulations indicate that a large fraction of the alpha energy can be converted to rotation energy. © 2010

  5. Measurement of magnetic field produced by the interaction of ultra-short, ultra-intense fs laser pulse with matter

    SciTech Connect (OSTI)

    Zamponi, F.; Luebcke, A.; Uschmann, I.; Foerster, E.; Sauerbrey, R. [Institut fuer Optik und Quantenelektronik, Max-Wien-Platz, 1 07743 Jena (Germany); Kroupp, E.; Stambulchik, E.; Maron, Y. [Weizmann Institute of Science Rehovot 76100 (Israel); Fisher, D. [Soreq, NRC, Yavne 81800 (Israel)

    2006-04-07

    We report on the preliminary results of a first experiment where the Zeeman effect in the X-ray range was exploited to monitor the quasi static magnetic field, created by the interaction of an ultra-short (80 fs) ultra-intense fs laser pulse with solid matter.The involved laser intensities ranged between 1018 and 5{center_dot}1019 W/cm2. The target was a 25 {mu}m thick Ti foil. We monitored the X-ray emissions of the K{alpha}1 and K{alpha}2 lines by means of a spectrometer with 0.3 eV energy resolution and 20 {mu}m spatial resolution. The spectrometer was composed by a toroidally bent GaAs crystal and a Si plane crystal in dispersionless setup at 45 deg., working as polarizer, to distinguish contribution to the line broadening coming from other mechanisms.We observe an increasing broadening of the linewidth in dependence of the intensity but no differences between polarized and non-polarized spectra, probably because of a too low spatial resolution. A linewidth increase was measured to be 30%. We are working to determine the role of mechanisms other than the Zeeman effect in the measurements. Possible mechanisms causing line broadening, i.e. Stark effect, satellite lines, are discussed.If the Zeeman effect was the main cause for the measured line broadening, a magnetic field of 5000 tesla would be expected.

  6. Evaluation of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and Moderate Resolution Imaging Spectrometer

    E-Print Network [OSTI]

    Evaluation of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and Moderate Resolution the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and the Moderate Resolution Imaging Spectrometer (MODIS). Key goals were to assess the nature of these relationships as they varied between sensors

  7. Birefringent Fourier-transform imaging spectrometer

    E-Print Network [OSTI]

    Harvey, Andy

    Birefringent Fourier-transform imaging spectrometer Andrew Robert Harvey and David William Fletcher.r.Harvey@hw.ac.uk http://www.ece.eps.hw.ac.uk/~arharvey Abstract: Fourier-transform imaging spectrometers offer important, for application in harsh environments, deployment of Fourier-transform instruments based on traditional moving

  8. Event counting alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; MacArthur, D.W.

    1996-08-27

    An electrostatic detector is disclosed for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure. 6 figs.

  9. Event counting alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); MacArthur, Duncan W. (Los Alamos, NM)

    1996-01-01

    An electrostatic detector for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure.

  10. Nuclear diagnostic for fast alpha particles

    DOE Patents [OSTI]

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

    1986-01-01

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

  11. Design and operational characteristics of a cast steel mass spectrometer

    SciTech Connect (OSTI)

    Blantocas, Gene Q.; Ramos, Henry J.; Wada, Motoi

    2004-09-01

    A cast steel magnetic sector mass analyzer is developed for studies of hydrogen and helium ion beams generated by a gas discharge compact ion source. The optimum induced magnetic flux density of 3500 G made it possible to scan the whole spectrum of hydrogen and helium ion species. Analysis of beam characteristics shows that the mass spectrometer sensitivity, and resolving power are approximately inversely proportional. The resolution is enhanced at higher pressures and lower current discharges. In contrast, the instrument sensitivity increased at higher current discharges and decreased at higher pressures. Calculations of the ultimate resolving power with reference to analyzer dimensions yield a numerical value of 30. System anomaly in the form of spherical aberrations was also analyzed using the paraxial beam envelope equation. Beam divergence is most significant at high discharge conditions where angular spread reaches an upper limit of 8.6 deg.

  12. Improving Alpha Spectrometry Energy Resolution by Ion Implantation with ICP-MS

    SciTech Connect (OSTI)

    Dion, Michael P.; Liezers, Martin; Farmer, Orville T.; Miller, Brian W.; Morley, Shannon M.; Barinaga, Charles J.; Eiden, Gregory C.

    2015-01-01

    We report results of a novel technique using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) as a method of source preparation for alpha spectrometry. This method produced thin, contaminant free 241Am samples which yielded extraordinary energy resolution which appear to be at the lower limit of the detection technology used in this research.

  13. An Engine Exhaust Particle SizerTM Spectrometer for Transient...

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

    An Engine Exhaust Particle SizerTM Spectrometer for Transient Emission Particle Measurements An Engine Exhaust Particle SizerTM Spectrometer for Transient Emission Particle...

  14. Making Mobile Measurement Using an EEPS Spectrometer | Department...

    Energy Savers [EERE]

    Using an EEPS Spectrometer Making Mobile Measurement Using an EEPS Spectrometer 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: TSI Incorporated...

  15. An electron/ion spectrometer with the ability of low energy electron measurement for fast ignition experiments

    SciTech Connect (OSTI)

    Ozaki, T.; Sakagami, H. [National Institute for Fusion Science, 322-6, Oroshi, Toki, Gifu 509-5292 (Japan); Kojima, S.; Arikawa, Y.; Shiraga, H.; Fujioka, S. [Institute of Laser Engineering, Osaka University, 2-6, Yamada-oka, Suita, Osaka 565-0871 (Japan); Kato, R., E-mail: ozaki@nifs.ac.jp [Institute of Scientific and Industrial Research, Osaka University, 8-1, Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2014-11-15

    An electron energy spectrometer (ESM) is one of the most fundamental diagnostics in the fast ignition experiment. It is necessary to observe the spectra down to a low energy range in order to obtain the accurate deposition efficiency toward the core. Here, we realize the suitable ESM by using a ferrite magnet with a moderate magnetic field of 0.3 T and a rectangular magnetic circuit covered with a steel plate in the inlet side.

  16. THE PERFORMANCE OF THE AMS-02 TRD P. RAPAGNANI

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    , Universitŕ La Sapienza, INFN, Sez. Roma P.za A. Moro 2, I-00185 Rome, Italy The Alpha Magnetic Spectrometer, and so far within specifications and schedule. 1. Introduction The Alpha Magnetic Spectrometer (AMS-02

  17. Gas sampling system for a mass spectrometer

    DOE Patents [OSTI]

    2003-12-30

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

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

    SciTech Connect (OSTI)

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

    2012-11-10

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

  19. NEREUS Nemertes : embedded mass spectrometer control system

    E-Print Network [OSTI]

    Champy, Adam Samuel

    2005-01-01

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

  20. A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER

    E-Print Network [OSTI]

    O'Donnell, Tom

    A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER FOR PRODUCTION OF NEUTRON-RICH NUCLEI ( 136 Xe Superconducting Cyclotron Laboratory's weekly \\Green Sheet," 30 July 1999 #12; c Thomas W. O'Donnell 2000 All

  1. Ultra High Mass Range Mass Spectrometer System

    DOE Patents [OSTI]

    Reilly, Peter T. A. [Knoxville, TN

    2005-12-06

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

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

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

    The BRAHMS experiment was designed to measure charged hadrons over a wide range of rapidity and transverse momentum to study the reaction mechanisms of the relativistic heavy ion reactions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the properties of the highly excited nuclear matter formed in these reactions. The experiment took its first data during the RHIC 2000 year run and completed data taking in June 2006. The BRAHMS archive makes publications available and also makes data and figures from those publications available as separate items. See also the complete list of publications, multimedia presentations, and related papers at http://www4.rcf.bnl.gov/brahms/WWW/publications.html

  3. Performances of a bent-crystal spectrometer adapted to resonant x-ray emission measurements on gas-phase samples

    SciTech Connect (OSTI)

    Journel, Loiec; El Khoury, Lara; Marin, Thierry; Guillemin, Renaud; Carniato, Stephane; Avila, Antoine; Delaunay, Renaud; Hague, Coryn F.; Simon, Marc

    2009-09-15

    We describe a bent-crystal spectrometer adapted to measure x-ray emission resulting from core-level excitation of gas-phase molecules in the 0.8-8 keV energy range. The spectrometer is based on the Johann principle, and uses a microfocused photon beam to provide high-resolution (resolving power of {approx}7500). A gas cell was designed to hold a high-pressure (300 mbar) sample of gas while maintaining a high vacuum (10{sup -9} mbar) in the chamber. The cell was designed to optimize the counting rate (2000 cts/s at the maximum of the Cl K{alpha} emission line), while minimizing self-absorption. Example of the K{alpha} emission lines of CH{sub 3}Cl molecules is presented to illustrate the capabilities of this new instrument.

  4. The LASS (Larger Aperture Superconducting Solenoid) spectrometer

    SciTech Connect (OSTI)

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

    SciTech Connect (OSTI)

    Kleymenov, Evgeny; Bokhoven, Jeroen A. van; David, Christian; Janousch, Markus; Studer, Marco; Willimann, Markus; Bergamaschi, Anna; Henrich, Beat; Nachtegaal, Maarten; Glatzel, Pieter; Alonso-Mori, Roberto

    2011-06-15

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

  6. Compact hydrogen/helium isotope mass spectrometer

    DOE Patents [OSTI]

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

    1996-01-01

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

  7. Fast Neutron Detection with a Segmented Spectrometer

    E-Print Network [OSTI]

    T. J. Langford; C. D. Bass; E. J. Beise; H. Breuer; D. K. Erwin; C. R. Heimbach; J. S. Nico

    2014-11-20

    A fast neutron spectrometer consisting of segmented plastic scintillator and He-3 proportional counters was constructed for the measurement of neutrons in the energy range 1 MeV to 200 MeV. We discuss its design, principles of operation, and the method of analysis. The detector is capable of observing very low neutron fluxes in the presence of ambient gamma background and does not require scintillator pulseshape discrimination. The spectrometer was characterized for its energy response in fast neutron fields of 2.5 MeV and 14 MeV, and the results are compared with Monte Carlo simulations. Measurements of the fast neutron flux and energy response at 120 m above sea-level (39.130 deg. N, 77.218 deg. W) and at a depth of 560 m in a limestone mine are presented. Finally, the design of a spectrometer with improved sensitivity and energy resolution is discussed.

  8. AND FUSION TECHNOLOGY; MFTF DEVICES; DESIGN; DEUTERIUM; MAGNET...

    Office of Scientific and Technical Information (OSTI)

    MFTF-. cap alpha. + T progress report Nelson, W.D. (ed.) 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; MFTF DEVICES; DESIGN; DEUTERIUM; MAGNET COILS; MAINTENANCE; REACTOR FUELING;...

  9. Wide size range fast integrated mobility spectrometer

    SciTech Connect (OSTI)

    Wang, Jian

    2013-10-29

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

  10. The source-sample stage of the new two-dimensional angular correlation of annihilation radiation spectrometer at Technische Universitaet Muenchen

    SciTech Connect (OSTI)

    Ceeh, Hubert; Weber, Josef Andreas; Boeni, Peter [Technische Universitaet Muenchen, Lehrstuhl E21, James-Franck Strasse, 85747 Garching (Germany); Leitner, Michael [FRM II, Technische Universitaet Muenchen, Lichtenbergstrasse 1, 85747 Garching (Germany); Hugenschmidt, Christoph [Technische Universitaet Muenchen, Lehrstuhl E21, James-Franck Strasse, 85747 Garching (Germany); FRM II, Technische Universitaet Muenchen, Lichtenbergstrasse 1, 85747 Garching (Germany)

    2013-04-15

    Angular correlation of annihilation radiation (ACAR) is a well established technique for the investigation of the electronic structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. For this reason, the focus of this work is put on the discussion of a newly developed source-sample stage of the new 2D-ACAR spectrometer at Technische Universitaet Muenchen which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot diameter is d{sub FWHM}= 5.4 mm, with a high efficiency over the whole energy spectrum of the {sup 22}Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline {alpha}-quartz, which serves as a model system for the determination of the total resolution. A value of (1.53 Multiplication-Sign 1.64) mrad{sup 2} FWHM was achieved at room temperature.

  11. DC-based magnetic field controller

    DOE Patents [OSTI]

    Kotter, Dale K. (Shelley, ID); Rankin, Richard A. (Ammon, ID); Morgan, John P,. (Idaho Falls, ID)

    1994-01-01

    A magnetic field controller for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage.

  12. Lens system for a photo ion spectrometer

    DOE Patents [OSTI]

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

    1990-11-27

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

  13. Lens system for a photo ion spectrometer

    DOE Patents [OSTI]

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

    1990-01-01

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

  14. Development and performance of a miniature, low cost mass spectrometer

    E-Print Network [OSTI]

    Hemond, Brian D. (Brian David Thomson)

    2011-01-01

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

  15. Study of elementary reactions with the HADES dielectron spectrometer

    E-Print Network [OSTI]

    B. Ramstein

    2009-12-14

    Results obtained with the HADES dielectron spectrometer at GSI are discussed, with emphasis on dilepton production in elementary reactions.

  16. Surface alpha clustering

    SciTech Connect (OSTI)

    Rotter, I.

    1983-05-01

    The problem of alpha decay is discussed on the basis of a theory which describes discrete and continuous states in a unified manner. A formula for numerical calculations is given in which configurational mixing as well as channel coupling is taken into account. The R-matrix approximation is shown to be justified if the width is spread over a small number of decay channels. Generally, renormalization of the wave function is necessary if a factorization of the width is assumed. The importance of channel coupling for the case of a small reduced width is discussed.

  17. Fast-Ion Deuterium Alpha spectroscopic observations of the effects of fishbones in the Mega-Amp\\`ere Spherical Tokamak

    E-Print Network [OSTI]

    Jones, O M; McClements, K G; Conway, N J; Crowley, B; Akers, R J; Lake, R J; Pinches, S D

    2013-01-01

    Using the recently-installed Fast-Ion Deuterium Alpha (FIDA) spectrometer, the effects of low-frequency (20-50 kHz) chirping energetic particle modes with toroidal mode number n \\geq 1 on the fast-ion population in MAST plasmas are considered. Results from the FIDA diagnostic are presented and discussed in the light of the present theoretical understanding of these modes, known as fishbones, in plasmas with reversed shear. Measurements of the fast-ion population reveal losses of fast ions as well as strong redistribution in both real and velocity space as a result of the fishbones. Time-resolved measurements throughout the evolution of a fishbone show radial redistribution of fast ions with energies up to 95% of the primary beam injection energy. Correlations between fast-ion losses and the peak time derivative of the magnetic field perturbation are observed in a limited range of operating scenarios. The transient reduction in signal caused by a fishbone may in some cases reach 50% of the signal intensity bef...

  18. Portable gas chromatograph-mass spectrometer

    DOE Patents [OSTI]

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

    1996-01-01

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

  19. Imaging spectrometer wide field catadioptric design

    DOE Patents [OSTI]

    Chrisp; Michael P. (Danville, CA)

    2008-08-19

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

  20. Neutron spectrometer for improved SNM search.

    SciTech Connect (OSTI)

    Vance, Andrew L.; Aigeldinger, Georg

    2007-03-01

    With the exception of large laboratory devices with very low sensitivities, a neutron spectrometer have not been built for fission neutrons such as those emitted by special nuclear materials (SNM). The goal of this work was to use a technique known as Capture Gated Neutron Spectrometry to develop a solid-state device with this functionality. This required modifications to trans-stilbene, a known solid-state scintillator. To provide a neutron capture signal we added lithium to this material. This unique triggering signal allowed identification of neutrons that lose all of their energy in the detector, eliminating uncertainties that arise due to partial energy depositions. We successfully implemented a capture gated neutron spectrometer and were able to distinguish an SNM like fission spectrum from a spectrum stemming from a benign neutron source.

  1. Frequency-feedback cavity enhanced spectrometer

    DOE Patents [OSTI]

    Hovde, David Christian; Gomez, Anthony

    2015-08-18

    A spectrometer comprising an optical cavity, a light source capable of producing light at one or more wavelengths transmitted by the cavity and with the light directed at the cavity, a detector and optics positioned to collect light transmitted by the cavity, feedback electronics causing oscillation of amplitude of the optical signal on the detector at a frequency that depends on cavity losses, and a sensor measuring the oscillation frequency to determine the cavity losses.

  2. Introduction to Subatomic-Particle Spectrometers

    E-Print Network [OSTI]

    Daniel M. Kaplan; Charles. E. Lane; Kenneth S. Nelson

    2015-07-17

    An introductory review, suitable for the beginning student of high-energy physics or professionals from other fields who may desire familiarity with subatomic-particle detection techniques. Subatomic-particle fundamentals and the basics of particle interactions with matter are summarized, after which we review particle detectors. We conclude with three examples that illustrate the variety of subatomic-particle spectrometers and exemplify the combined use of several detection techniques to characterize interaction events more-or-less completely.

  3. Capillary zone electrophoresis-mass spectrometer interface

    DOE Patents [OSTI]

    D`Silva, A.

    1996-08-06

    A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conductors is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer. 1 fig.

  4. Magnetic Field Amplification via Protostellar Disc Dynamos

    E-Print Network [OSTI]

    Dyda, Sergei; Ustyugova, Galina V; Koldoba, Alexander V; Wasserman, Ira

    2015-01-01

    We model the generation of a magnetic field in a protostellar disc using an \\alpha-dynamo and perform axisymmetric magnetohydrodynamics (MHD) simulations of a T Tauri star. We find that for small values of the dimensionless dynamo parameter $\\alpha_d$ the poloidal field grows exponentially at a rate ${\\sigma} \\propto {\\Omega}_K \\sqrt{\\alpha_d}$ , before saturating to a value $\\propto \\sqrt{\\alpha_d}$ . The dynamo excites dipole and octupole modes, but quadrupole modes are suppressed, because of the symmetries of the seed field. Initial seed fields too weak to launch MHD outflows are found to grow sufficiently to launch winds with observationally relevant mass fluxes of order $10^{-9} M_{\\odot}/\\rm{yr}$ for T Tauri stars. For large values of $\\alpha_d$ magnetic loops are generated over the entire disc. These quickly come to dominate the disc dynamics and cause the disc to break up due to the magnetic pressure.

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

    DOE Patents [OSTI]

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

    1983-11-16

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

  6. Expert overseer for mass spectrometer system

    DOE Patents [OSTI]

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

    1991-01-01

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

  7. Superconducting Gamma/Neutron Spectrometer Task 1 Completion Report Evaluation of Candidate Neutron-Sensitive Materials

    SciTech Connect (OSTI)

    Bell, Z.W.; Lamberti, V.E.

    2002-06-20

    A review of the scientific literature regarding boron- and lithium-containing compounds was completed. Information such as Debye temperature, heat capacity, superconductivity properties, physical and chemical characteristics, commercial availability, and recipes for synthesis was accumulated and evaluated to develop a list of neutron-sensitive materials likely to perform properly in the spectrometer. The best candidate borides appear to be MgB{sub 2} (a superconductor with T{sub c} = 39 K), B{sub 6}Si, B{sub 4}C, and elemental boron; all are commercially available. Among the lithium compounds are LiH, LiAl, Li{sub 12}Si{sub 7}, and Li{sub 7}Sn{sub 2}. These materials have or are expected to have high Debye temperatures and sufficiently low heat capacities at 100 mK to produce a useful signal. The responses of {sup 10}B and {sup 6}Li to a fission neutron spectrum were also estimated. These demonstrated that the contribution of scattering events is no more than 3% in a boron-based system and 1.5% in a lithium-based system. This project is concerned with the development of materials for use in a cryogenic neutron spectrometer and is complementary to work in progress by Labov at LLNL to develop a cryogenic gamma ray spectrometer. Refrigeration to 100 mK lowers the heat capacity of these materials to the point that the energy of absorbed gamma and x rays, nuclei scattered by fast neutrons, and ions from (n, {alpha}) reactions produce a measurable heat pulse, from which the energy of the incident radiation may be deduced. The objective of this project is the discovery, fabrication, and testing of candidate materials with which a cryogenic neutron spectrometer may be realized.

  8. Performance of the new 2D ACAR spectrometer in Munich

    E-Print Network [OSTI]

    Ceeh, Hubert; Leitner, Michael; Böni, Peter; Hugenschmidt, Christoph

    2012-01-01

    Angular Correlation of Annihilation Radiation (ACAR) is a well established technique for the investigation of the electric structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. Fore this reason, the focus of this work is put on the discussion of a newly developed source-sample stage which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot size is $d_{\\mathrm{FWHM}}=5.4\\,$mm, with a high efficiency over the whole energy spectrum of the $^{22}$Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline $\\alpha$-quartz, which serves as a model system for the determination of the total resolution.

  9. Performance of the new 2D ACAR spectrometer in Munich

    E-Print Network [OSTI]

    Hubert Ceeh; Josef-Andreas Weber; Michael Leitner; Peter Böni; Christoph Hugenschmidt

    2012-10-12

    Angular Correlation of Annihilation Radiation (ACAR) is a well established technique for the investigation of the electric structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. Fore this reason, the focus of this work is put on the discussion of a newly developed source-sample stage which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot size is $d_{\\mathrm{FWHM}}=5.4\\,$mm, with a high efficiency over the whole energy spectrum of the $^{22}$Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline $\\alpha$-quartz, which serves as a model system for the determination of the total resolution.

  10. Size dependence in the stabilities and electronic properties of \\alpha-graphyne and its BN analogue

    E-Print Network [OSTI]

    Özçelik, V Ongun

    2013-01-01

    We predict the stabilities of \\alpha-graphynes and their boron nitride analogues(\\alpha-BNyne), which are considered as competitors of graphene and two-dimensional hexagonal BN. Based on first-principles plane wave method, we investigated the stability and structural transformations of these materials at different sizes using phonon dispersion calculations and ab-initio finite temperature, molecular dynamics simulations. Depending on the number of additional atoms in the edges between the corner atoms of the hexagons, n, both \\alpha-graphyne(n) and \\alpha-BNyne(n) are stable for even n, but unstable for odd n. \\alpha-graphyne(3) undergoes a structural transformation, where the symmetry of hexagons is broken. We present the structure optimized cohesive energies, electronic, magnetic and mechanical properties of stable structures. Our calculations reveal the existence of Dirac cones in the electronic structures of \\alpha-graphynes of all sizes, where the Fermi velocities decrease with increasing n. The electron...

  11. Micro-optical-mechanical system photoacoustic spectrometer

    DOE Patents [OSTI]

    Kotovsky, Jack; Benett, William J.; Tooker, Angela C.; Alameda, Jennifer B.

    2013-01-01

    All-optical photoacoustic spectrometer sensing systems (PASS system) and methods include all the hardware needed to analyze the presence of a large variety of materials (solid, liquid and gas). Some of the all-optical PASS systems require only two optical-fibers to communicate with the opto-electronic power and readout systems that exist outside of the material environment. Methods for improving the signal-to-noise are provided and enable mirco-scale systems and methods for operating such systems.

  12. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1985-07-29

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and sway from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch.

  13. Lead Slowing Down Spectrometer Status Report

    SciTech Connect (OSTI)

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

    2012-06-07

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

  14. Compact proton spectrometers for measurements of shock

    SciTech Connect (OSTI)

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

    2012-05-02

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

  15. Photoacoustic Soot Spectrometer (PASS) Instrument Handbook

    SciTech Connect (OSTI)

    Dubey, M; Springston, S; Koontz, A; Aiken, A

    2013-01-17

    The photoacoustic soot spectrometer (PASS) measures light absorption by aerosol particles. As the particles pass through a laser beam, the absorbed energy heats the particles and in turn the surrounding air, which sets off a pressure wave that can be detected by a microphone. The PASS instruments deployed by ARM can also simultaneously measure the scattered laser light at three wavelengths and therefore provide a direct measure of the single-scattering albedo. The Operator Manual for the PASS-3100 is included here with the permission of Droplet Measurement Technologies, the instrument’s manufacturer.

  16. Dual waveband compact catadioptric imaging spectrometer

    DOE Patents [OSTI]

    Chrisp, Michael P.

    2012-12-25

    A catadioptric dual waveband imaging spectrometer that covers the visible through short-wave infrared, and the midwave infrared spectral regions, dispersing the visible through shortwave infrared with a zinc selenide grating and midwave infrared with a sapphire prism. The grating and prism are at the cold stop position, enabling the pupil to be split between them. The spectra for both wavebands are focused onto the relevant sections of a single dual waveband detector. Spatial keystone distortion is controlled to less than one tenth of a pixel over the full wavelength range, facilitating the matching of the spectra in the midwave infrared with the shorter wavelength region.

  17. Wide swath imaging spectrometer utilizing a multi-modular design

    DOE Patents [OSTI]

    Chrisp, Michael P. (Danville, CA)

    2010-10-05

    A wide swath imaging spectrometer utilizing an array of individual spectrometer modules in the telescope focal plane to provide an extended field of view. The spectrometer modules with their individual detectors are arranged so that their slits overlap with motion on the scene providing contiguous spatial coverage. The number of modules can be varied to take full advantage of the field of view available from the telescope.

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

    DOE Patents [OSTI]

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

    1986-04-22

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

  19. Fabrication, Testing and Modeling of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2010-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.IEEE Transactions on Applied Superconductivity 15, No. 2, p.AND MODELING OF THE MICE SUPERCONDUCTING SPECTROMETER

  20. MICROWAVE SPECTROMETER FOR THE DETECTION OF TRANSIENT GASEOUS SPECIES

    E-Print Network [OSTI]

    Kolbe, W.F.

    2011-01-01

    for Computer Control of Microwave Spectrometers, LBL-9276,and H. P. Broida, "Microwave Discharge Cavities Operating atJr. , and C. H. Townes, "Microwave Spectra of the Free

  1. The Results of Tests of the MICE Spectrometer Solenoids

    E-Print Network [OSTI]

    Green, Michael A.

    2010-01-01

    Rotary Valve 1st Stage Drop in Sleeve PS 300 A Fig.3 Quench protection circuit for the MICE spectrometer solenoids

  2. 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

    SciTech Connect (OSTI)

    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.; Mańá, 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.; Türko?lu, 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.

    2014-11-26

    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 ?= -3.170 ± 0.008(stat+syst) ± 0.008(energy scale).

  3. The TFTR E Parallel B Spectrometer for Mass and Energy Resolved Multi-Ion Charge Exchange Diagnostics

    SciTech Connect (OSTI)

    A.L. Roquemore; S.S. Medley

    1998-01-01

    The Charge Exchange Neutral Analyzer diagnostic for the Tokamak Fusion Test Reactor was designed to measure the energy distributions of both the thermal ions and the supra thermal populations arising from neutral-beam injection and ion cyclotron radio-frequency heating. These measurements yield the plasma ion temperature, as well as several other plasma parameters necessary to provide an understanding of the plasma condition and the performance of the auxiliary heating methods. For this application, a novel charge-exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory. The design and performance of this spectrometer is described in detail, including the effects of exposure of the microchannel plate detector to magnetic fields, neutrons, and tritium.

  4. 140 GHz pulsed fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, William F. (Oakland, CA); Leskovar, Branko (Moraga, CA)

    1987-01-01

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer (10), including means (11, 19) for generating a high frequency carrier signal, and means (12) for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator (20) and the modulating signal is fed through a pulse switch (23) to the modulator. When the pulse switch (23) is on, the modulator (20) will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device (31) is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device (31) is controlled by the pulse switch (23).

  5. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1987-10-27

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal is disclosed. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch. 5 figs.

  6. Solid state NMR spectrometer. Final project report

    SciTech Connect (OSTI)

    Jensen, C.M.

    1997-11-01

    The new Varian Unity INOVA 400 is being utilized on a daily basis. The instrument is available 24 hours a day seven days a week for scheduled experiments. In addition, a limited amount of time is available on a walk-in basis for researchers on the project. The instrument has operated with no down time since the end of the Varian installation process. Minor problems have been corrected by the facility staff (spent fused, malfunctioning boards and components and interrupted data transfers). Most of the initial problems were covered under the warrantee period. Since the end of this period there have been no major operational problems. This report discusses two research projects using the new spectrometer: dynamics of dihydrogen and alkane complexes of iridium and catalytic dehydrogenation by iridium hydride complexes.

  7. Mass spectrometer vacuum housing and pumping system

    DOE Patents [OSTI]

    Coutts, Gerald W. (Livermore, CA); Bushman, John F. (Oakley, CA); Alger, Terry W. (Tracy, CA)

    1996-01-01

    A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.

  8. Mass spectrometer vacuum housing and pumping system

    DOE Patents [OSTI]

    Coutts, G.W.; Bushman, J.F.; Alger, T.W.

    1996-07-23

    A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.

  9. ALPHA-PARTICLE RADIOBIOLOGICAL EXPERIMENTS USING THIN CR-39 DETECTORS

    E-Print Network [OSTI]

    Yu, Peter K.N.

    sterilisation. For alpha-particle radiobiological experiments, it is easier to quantify the alpha energies

  10. LANL/Green Star spectrometer tests

    SciTech Connect (OSTI)

    Sampson, T.E.; Cremers, T.L.; Vo, D.T. [Los Alamos National Lab., NM (United States); Seldiakov, Y.P.; Dorin, A.B.; Kondrashov, M.V. [Green Star, Moscow (Russian Federation); Timoshin, V.I. [VNIINM, Moscow (Russian Federation)

    1997-12-01

    The US and Russia have agreed to the joint development of a nondestructive assay system for use to support the dismantlement of nuclear weapons in Russia. This nondestructive assay system will be used to measure plutonium produced by the conversion of Russian nuclear weapons. The NDA system for Russia will be patterned after the ARIES NDA system being constructed at Los Alamos. One goal of the program is to produce an NDA system for use in Russia that maximizes the use of Russian resources to facilitate maintenance and future upgrades. The Green Star SBS50 Single Board Spectrometer system (Green Star Ltd., Moscow, Russia) has been suggested for use as the data acquisition component for gamma ray instruments in the system. Possible uses are for plutonium isotopic analysis and also segmented gamma scanning. Green Star has also developed analysis software for the SBS50. This software, both plutonium isotopic analysis and uranium enrichment analysis, was developed specifically for customs/border inspection applications (low counting rate applications and identification as opposed to quantification) and was not intended for MC and A applications. Because of the relative immaturity of the Green Star plutonium isotopic analysis software (it has been under development for only one year and is patterned after US development circa 1980), it was tentatively agreed, before the tests, that the Russian NDA system would use the Los Alamos PC/FRAM software for plutonium isotopic analysis. However, it was also decided to include the Green Star plutonium isotopic software in the testing, both to quantify its performance for MC and A applications and also to provide additional data to Green Star for further development of their software. The main purpose of the testing was to evaluate the SBS-50 spectrometer as a data acquisition device for use with LANL software.

  11. A direct digital synthesis chirped pulse Fourier transform microwave spectrometer

    E-Print Network [OSTI]

    Blake, Geoffrey

    A direct digital synthesis chirped pulse Fourier transform microwave spectrometer Ian A. Finneran OF SCIENTIFIC INSTRUMENTS 84, 083104 (2013) A direct digital synthesis chirped pulse Fourier transform microwave pulse Fourier transform microwave (CP-FTMW) spectrometers have become the instrument of choice

  12. Neutron Sciences THE HYSPEC POLARIZED BEAM SPECTROMETER AT THE SNS

    E-Print Network [OSTI]

    Johnson, Peter D.

    Neutron Sciences THE HYSPEC POLARIZED BEAM SPECTROMETER AT THE SNS M.E. Hagen(1), S.M. Shapiro(2 Neutron Source, Oak Ridge National Lab., P.O. Box 2008, Oak Ridge, TN 37831, U.S.A (2)Dept. of Condensed spectrometer that utilizes Bragg focusing optics to obtain a high intensity at the sample position for neutron

  13. Workshop on high-resolution, large-acceptance spectrometers

    SciTech Connect (OSTI)

    Zeidman, B. (ed.)

    1981-01-01

    The purpose of the Workshop on High-Resolution, Large-Acceptance Spectrometers was to provide a means for exchange of information among those actively engaged in the design and construction of these new spectrometers. Thirty-seven papers were prepared for the data base.

  14. Ion mobility spectrometer, spectrometer analyte detection and identification verification system, and method

    DOE Patents [OSTI]

    Atkinson, David A. (Idaho Falls, ID)

    2002-01-01

    Methods and apparatus for ion mobility spectrometry and analyte detection and identification verification system are disclosed. The apparatus is configured to be used in an ion mobility spectrometer and includes a plurality of reactant reservoirs configured to contain a plurality of reactants which can be reacted with the sample to form adducts having varying ion mobilities. A carrier fluid, such as air or nitrogen, is used to carry the sample into the spectrometer. The plurality of reactants are configured to be selectively added to the carrier stream by use inlet and outlet manifolds in communication with the reagent reservoirs, the reservoirs being selectively isolatable by valves. The invention further includes a spectrometer having the reagent system described. In the method, a first reactant is used with the sample. Following a positive result, a second reactant is used to determine whether a predicted response occurs. The occurrence of the second predicted response tends to verify the existence of a component of interest within the sample. A third reactant can also be used to provide further verification of the existence of a component of interest. A library can be established of known responses of compounds of interest with various reactants and the results of a specific multi-reactant survey of a sample can be compared against the library to determine whether a component detected in the sample is likely to be a specific component of interest.

  15. Ellerman Bombs - Evidence for Magnetic Reconnection in the Lower Solar Atmosphere

    E-Print Network [OSTI]

    Nelson, C J; Mathioudakis, M; Doyle, J G; Madjarska, M S; Uitenbroek, H; Erdélyi, R

    2013-01-01

    The presence of photospheric magnetic reconnection has long been thought to give rise to short and impulsive events, such as Ellerman bombs (EBs) and Type II spicules. In this article, we combine high-resolution, high-cadence observations from the Interferometric BIdimensional Spectrometer (IBIS) and Rapid Oscillations in the Solar Atmosphere (ROSA) instruments at the Dunn Solar Telescope, National Solar Observatory, New Mexico with co-aligned Atmospheric Imaging Assembly (SDO/AIA) and Solar Optical Telescope (Hinode/SOT) data to observe small-scale events situated within an active region. These data are then compared with state-of-the-art numerical simulations of the lower atmosphere made using the MURaM code. It is found that brightenings, in both the observations and the simulations, of the wings of the H alpha line profile, interpreted as EBs, are often spatially correlated with increases in the intensity of the FeI 6302.5A line core. Bi-polar regions inferred from Hinode/SOT magnetic field data show evid...

  16. Open-split interface for mass spectrometers

    DOE Patents [OSTI]

    Diehl, John W. (Grand Forks, ND)

    1991-01-01

    An open-split interface includes a connector body having four leg members projecting therefrom within a single plane, the first and third legs being coaxial and the second and fourth legs being coaxial. A tubular aperture extends through the first and third legs and a second tubular aperture extends through the second and fourth legs, connecting at a juncture within the center of the connector body. A fifth leg projects from the connector body and has a third tubular aperture extending therethrough to the juncture of the first and second tubular apertures. A capillary column extends from a gas chromatograph into the third leg with its end adjacent the juncture. A flow restrictor tube extends from a mass spectrometer through the first tubular aperture in the first and third legs and into the capillary columnm end, so as to project beyond the end of the third leg within the capillary column. An annular gap between the tube and column allows excess effluent to pass to the juncture. A pair of short capillary columns extend from separate detectors into the second tubular aperture in the second and fourth legs, and are oriented with their ends spaced slightly from the first capillary column end. A sweep flow tube is mounted in the fifth leg so as to supply a helium sweep flow to the juncture.

  17. High resolving power spectrometer for beam analysis

    SciTech Connect (OSTI)

    Moshammer, H.W.; Spencer, J.E.

    1992-03-01

    We describe a system designed to analyze the high energy, closely spaced bunches from individual RF pulses. Neither a large solid angle nor momentum range is required so this allows characteristics that appear useful for other applications such as ion beam lithography. The spectrometer is a compact, double-focusing QBQ design whose symmetry allows the Quads to range between F or D with a correspondingly large range of magnifications, dispersion and resolving power. This flexibility insures the possibility of spatially separating all of the bunches along the focal plane with minimal transverse kicks and bending angle for differing input conditions. The symmetry of the system allows a simple geometric interpretationof the resolving power in terms of thin lenses and ray optics. We discuss the optics and the hardware that is proposed to measure emittance, energy, energy spread and bunch length for each bunch in an RF pulse train for small bunch separations. We also discuss how to use such measurements for feedback and feedforward control of these bunch characteristics as well as maintain their stability. 2 refs.

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

    E-Print Network [OSTI]

    V. Yu. Denisov; H. Ikezoe

    2005-10-27

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

  19. Alpha Gamma Hot Cell Facility

    E-Print Network [OSTI]

    Kemner, Ken

    . These operations can result in elevated radiological risks to the facility and workers. ARG-US -- meaning and should be developed for and deployed in nuclear and radiological facilities to aid operation and reduceAlpha Gamma Hot Cell Facility Argonne National Laboratory is a U.S. Department of Energy laboratory

  20. The FIRE infrared spectrometer at Magellan: construction and commissioning

    E-Print Network [OSTI]

    Simcoe, Robert A.

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

  1. Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane

    E-Print Network [OSTI]

    Texas at Austin, University of

    Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane 1 Funded by Environmental-infrared absorption spectrum of methane at 1665.5nm. · Guided mode design in SOI wafer #12;9 Device Fabrication Steps

  2. Diamond neutral particle spectrometer for fusion reactor ITER

    SciTech Connect (OSTI)

    Krasilnikov, V.; Amosov, V.; Kaschuck, Yu.; Skopintsev, D. [Institution PROJECT CENTER ITER, 1, Akademik Kurchatov Sq., Moscow (Russian Federation)

    2014-08-21

    A compact diamond neutral particle spectrometer with digital signal processing has been developed for fast charge-exchange atoms and neutrons measurements at ITER fusion reactor conditions. This spectrometer will play supplementary role for Neutral Particle Analyzer providing 10 ms time and 30 keV energy resolutions for fast particle spectra in non-tritium ITER phase. These data will also be implemented for independent studies of fast ions distribution function evolution in various plasma scenarios with the formation of a single fraction of high-energy ions. In tritium ITER phase the DNPS will measure 14 MeV neutrons spectra. The spectrometer with digital signal processing can operate at peak counting rates reaching a value of 10{sup 6} cps. Diamond neutral particle spectrometer is applicable to future fusion reactors due to its high radiation hardness, fast response and high energy resolution.

  3. Tunable light source for use in photoacoustic spectrometers

    DOE Patents [OSTI]

    Bisson, Scott E.; Kulp, Thomas J.; Armstrong, Karla M.

    2005-12-13

    The present invention provides a photoacoustic spectrometer that is field portable and capable of speciating complex organic molecules in the gas phase. The spectrometer has a tunable light source that has the ability to resolve the fine structure of these molecules over a large wavelength range. The inventive light source includes an optical parametric oscillator (OPO) having combined fine and coarse tuning. By pumping the OPO with the output from a doped-fiber optical amplifier pumped by a diode seed laser, the inventive spectrometer is able to speciate mixtures having parts per billion of organic compounds, with a light source that has a high efficiency and small size, allowing for portability. In an alternative embodiment, the spectrometer is scanned by controlling the laser wavelength, thus resulting in an even more compact and efficient design.

  4. Mass spectrometer having a derivatized sample presentation apparatus

    DOE Patents [OSTI]

    Nelson, Randall W. (Phoenix, AZ)

    2000-07-25

    A mass spectrometer having a derivatized sample presentation apparatus is provided. The sample presentation apparatus has a complex bound to the surface of the sample presentation apparatus. This complex includes a molecule which may chemically modify a biomolecule.

  5. Simulations of Alpha Wall Load in ITER. Final report

    SciTech Connect (OSTI)

    Carlsson, Johan

    2010-10-20

    The partially DOE funded International Thermonuclear Experimental Reactor (ITER) will produce massive amounts of energetic charged alpha particles, which are imperfectly confined by a strong magnetic field. The wall of the experiment is designed to withstand an estimated wall load from these fusion alpha particles, but the accuracy of this estimate needs to be improved to avoid potentially catastrophic surprises when the experiment becomes operational. We have added a more accurate, gyro-dynamic model of particle motion to the existing drift-dynamic model in the DELTA5D simulation software used for the project. We have also added the ability to load a detailed engineering model of the wall and use it in the simulations.

  6. Antihydrogen Trapped in the ALPHA Experiment

    ScienceCinema (OSTI)

    None

    2011-04-25

    In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i]  Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome.   The unique design features of the ALPHA apparatus will be explained.[ii]  These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise the perturbations to trapped charged particles which may cause particle loss and heating[iv].   The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried.   The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures',                                   G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii]  'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106, 025002 (2011) Organizer: Ferdinand Hahn PH/DT Detector Seminar webpage  

  7. Compact standing-wave transform spectrometer based on integrated MEMS mirror and thin-film photodetector

    E-Print Network [OSTI]

    Miller, David A. B.

    Compact standing-wave transform spectrometer based on integrated MEMS mirror and thin an integrated standing-wave Fourier-transform spectrometer, 17 × 13 × 2 mm, with 32 nm spectral resolution spectrometer, based on the 1-D standing-wave transform spectrometer architecture [1], with an integrated

  8. Using the Tremaine-Weinberg method to measure pattern speeds from H\\alpha velocity maps

    E-Print Network [OSTI]

    Beckman, John; Pińol, Nuria; Hernandez, Olivier; Carignan, Claude; Pérez, Isabel

    2008-01-01

    The Tremaine-Weinberg method is a well-known model independent technique for measuring density wave pattern speeds in spiral galaxies. Here we show how it can be applied to the data cubes (maps of surface brightness and velocity) obtained in H-alpha emission using a Fabry-Perot spectrometer. One of the main difficulties, the discontinuity of the H-alpha emission, is resolved using the neighbouring stellar continuum delivered by the data cube. We argue from symmetry that the motions not associated with the density wave should cancel. We show that our pattern speeds are reasonable by computing corotation radii, and comparing them to measured bar lengths. Simulations including star forming gas also add credibility to our results. Nevertheless it will be necessary to compare them with results using the spectra of the stellar components to quantify any systematic deviations from valid pattern speed values.

  9. THE AMS-02 TRANSITION RADIATION DETECTOR FOR THE INTERNATIONAL SPACE STATION

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    The Alpha Magnetic Spectrometer (AMS-02) is a large experiment in the International Space Station (ISS is presented 1. Introduction The Alpha Magnetic Spectrometer is an experiment which will be mounted composite/aluminum honeycomb octagonal support, fixed by an M-structure to the AMS-02 magnet flange. A space

  10. Cosmic magnetism

    SciTech Connect (OSTI)

    Seymour, P.

    1986-01-01

    This book deals with the cosmic magnetism in a non-mathematical way. It uses Faraday's very powerful and highly pictorial concept of lines of magnetic force and their associated physical properties to explain the structure and behavior of magnetic fields in extraterrestrial objects. Contents include: forces of nature; magnetic field of earth; solar and interplanetary magnetic fields; magnetic fields in the solar system; stars and pulsars; and magnetic fields of the milky way and other galaxies.

  11. EXTENDING THE USEFUL LIFE OF OLDER MASS SPECTROMETERS

    SciTech Connect (OSTI)

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

    2010-06-17

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

  12. Method for increasing the dynamic range of mass spectrometers

    DOE Patents [OSTI]

    Belov, Mikhail; Smith, Richard D.; Udseth, Harold R.

    2004-09-07

    A method for enhancing the dynamic range of a mass spectrometer by first passing a sample of ions through the mass spectrometer having a quadrupole ion filter, whereupon the intensities of the mass spectrum of the sample are measured. From the mass spectrum, ions within this sample are then identified for subsequent ejection. As further sampling introduces more ions into the mass spectrometer, the appropriate rf voltages are applied to a quadrupole ion filter, thereby selectively ejecting the undesired ions previously identified. In this manner, the desired ions may be collected for longer periods of time in an ion trap, thus allowing better collection and subsequent analysis of the desired ions. The ion trap used for accumulation may be the same ion trap used for mass analysis, in which case the mass analysis is performed directly, or it may be an intermediate trap. In the case where collection is an intermediate trap, the desired ions are accumulated in the intermediate trap, and then transferred to a separate mass analyzer. The present invention finds particular utility where the mass analysis is performed in an ion trap mass spectrometer or a Fourier transform ion cyclotron resonance mass spectrometer.

  13. Alpha

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TA I N P A T TSorbentsAllosteric Modulation ofOeffect

  14. A comparison of four direct geometry time-of-flight spectrometers at the Spallation Neutron Source

    SciTech Connect (OSTI)

    Stone, Matthew B [ORNL; Niedziela, Jennifer L [ORNL; Abernathy, Douglas L [ORNL; Debeer-Schmitt, Lisa M [ORNL; Garlea, Vasile O [ORNL; Granroth, Garrett E [ORNL; Graves-Brook, Melissa K [ORNL; Ehlers, Georg [ORNL; Kolesnikov, Alexander I [ORNL; Podlesnyak, Andrey A [ORNL; Winn, Barry L [ORNL

    2014-04-01

    The Spallation Neutron Source at Oak Ridge National Laboratory now hosts four direct geometry time-of-flight chopper spectrometers. These instruments cover a range of wave vector and energy transfer space with varying degrees of neutron flux and resolution. The regions of reciprocal and energy space available to measure at these instruments is not exclusive and overlaps significantly. We present a direct comparison of the capabilities of this instrumentation, conducted by data mining the instrument usage histories, and specific scanning regimes. In addition, one of the common science missions for these instruments is the study of magnetic excitations in condensed matter systems. We have measured the powder averaged spin wave spectra in one particular sample using each of these instruments, and use these data in our comparisons.

  15. A comparison of four direct geometry time-of-flight spectrometers at the Spallation Neutron Source

    SciTech Connect (OSTI)

    Stone, M. B.; Abernathy, D. L.; Ehlers, G.; Garlea, O.; Podlesnyak, A.; Winn, B. [Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Niedziela, J. L.; DeBeer-Schmitt, L.; Graves-Brook, M. [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Granroth, G. E. [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Kolesnikov, A. I. [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2014-04-15

    The Spallation Neutron Source at Oak Ridge National Laboratory now hosts four direct geometry time-of-flight chopper spectrometers. These instruments cover a range of wave-vector and energy transfer space with varying degrees of neutron flux and resolution. The regions of reciprocal and energy space available to measure at these instruments are not exclusive and overlap significantly. We present a direct comparison of the capabilities of this instrumentation, conducted by data mining the instrument usage histories, and specific scanning regimes. In addition, one of the common science missions for these instruments is the study of magnetic excitations in condensed matter systems. We have measured the powder averaged spin wave spectra in one particular sample using each of these instruments, and use these data in our comparisons.

  16. The Results of Recent MICE Superconducting Spectrometer Solenoid Test

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01

    nitrogen in the tank attached to the shield. From theshields of magnet 2 were that magnet 2 has an added liquid nitrogen tank

  17. Wavelength calibration of the JWST-MIRI medium resolution spectrometer

    E-Print Network [OSTI]

    Martinez-Galarza, J R; Hernan-Caballero, A; Azzollini, R; Glasse, A; Kendrew, S; Brandl, B; Lahuis, F

    2010-01-01

    We present the wavelength and spectral resolution characterisation of the Integral Field Unit (IFU) Medium Resolution Spectrometer for the Mid-InfraRed Instrument (MIRI), to fly onboard the James Webb Space Telescope in 2014. We use data collected using the Verification Model of the instrument and develop an empirical method to calibrate properties such as wavelength range and resolving power in a portion of the spectrometer's full spectral range (5-28 microns). We test our results against optical models to verify the system requirements and combine them with a study of the fringing pattern in the instrument's detector to provide a more accurate calibration. We show that MIRI's IFU spectrometer will be able to produce spectra with a resolving power above R=2800 in the wavelength range 6.46-7.70 microns, and that the unresolved spectral lines are well fitted by a Gaussian profile.

  18. Photo-Spectrometer Realized In A Standard Cmos Ic Process

    DOE Patents [OSTI]

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

    1999-10-12

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

  19. Sample introducing apparatus and sample modules for mass spectrometer

    DOE Patents [OSTI]

    Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

    1993-01-01

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus.

  20. Sample introducing apparatus and sample modules for mass spectrometer

    DOE Patents [OSTI]

    Thompson, C.V.; Wise, M.B.

    1993-12-21

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus. 5 figures.

  1. Development of multichannel low-energy neutron spectrometer

    SciTech Connect (OSTI)

    Arikawa, Y., E-mail: arikawa-y@ile.osaka-u.ac.jp; Nagai, T.; Abe, Y.; Kojima, S.; Sakata, S.; Inoue, H.; Utsugi, M.; Iwasa, Y.; Sarukura, N.; Nakai, M.; Shiraga, H.; Fujioka, S.; Azechi, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka (Japan); Murata, T. [Kumamoto University, 2-40-1 Kurokami, Kumamoto 860-8555 (Japan)

    2014-11-15

    A multichannel low-energy neutron spectrometer for down-scattered neutron (DSN) measurements in inertial confinement fusion (ICF) experiments has been developed. Our compact-size 256-channel lithium-glass-scintillator-based spectrometer has been implemented and tested in ICF experiments with the GEKKO XII laser. We have performed time calibration of the 256-channel analog-to-digital convertor system used for DSN measurements via X-ray pulse signals. We have clearly observed the DD-primary fusion neutron signal and have successfully studied the detector's impulse response. Our detector is soon to be implemented in future ICF experiments.

  2. Bragg x-ray survey spectrometer for ITER

    SciTech Connect (OSTI)

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

    2012-10-15

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

  3. Waveguide-integrated photonic crystal spectrometer with camera readout

    SciTech Connect (OSTI)

    Meng, Fan; Shiue, Ren-Jye; Li, Luozhou; Nie, Jing; Harris, Nicholas C.; Chen, Edward H.; Schröder, Tim; Englund, Dirk; Wan, Noel; Pervez, Nadia; Kymissis, Ioannis

    2014-08-04

    We demonstrate an infrared spectrometer based on waveguide-coupled nanocavity filters in a planar photonic crystal structure. The input light is coupled into the waveguide, from which spectral components are dropped into the cavities and radiated off-chip for detection on a commercial InGaAs camera. The spectrometer has a footprint of only 60??m by 8??m. The spectral resolution is about 1?nm in the operation bandwidth of 1522–1545?nm. By substituting the membrane material and structure parameters, this design can be easily extended into the visible regime and developed for a variety of highly efficient, miniature photonic applications.

  4. A broadband FFT spectrometer for radio and millimeter astronomy

    E-Print Network [OSTI]

    Arnold O. Benz; Paolo C. Grigis; V. Hungerbuhler; Hansueli Meyer; Cristian Monstein; Bruno Stuber; D. Zardet

    2005-09-22

    The core architecture, tests in the lab and first results of a Fast Fourier Transform (FFT) spectrometer are described. It is based on a commercially available fast digital sampler (AC240) with an on-board Field Programmable Gate Array (FPGA). The spectrometer works continuously and has a remarkable total bandwidth of 1 GHz, resolved into 16384 channels. The data is sampled with 8 bits, yielding a dynamic range of 48 dB. An Allan time of more than 2000 s and an SFDR of 37 dB were measured. First light observations with the KOSMA telescope show a perfect spectrum without internal or external spurious signals.

  5. Model of driven and decaying magnetic turbulence in a cylinder

    SciTech Connect (OSTI)

    Kemel, Koen; Brandenburg, Axel [NORDITA, AlbaNova University Center, Roslagstullsbacken 23, SE-10691 Stockholm (Sweden); Department of Astronomy, Stockholm University, SE 10691 Stockholm (Sweden); Ji Hantao [Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

    2011-11-15

    Using mean-field theory, we compute the evolution of the magnetic field in a cylinder with outer perfectly conducting boundaries and imposed axial magnetic and electric fields. The thus injected magnetic helicity in the system can be redistributed by magnetic helicity fluxes down the gradient of the local current helicity of the small-scale magnetic field. A weak reversal of the axial magnetic field is found to be a consequence of the magnetic helicity flux in the system. Such fluxes are known to alleviate so-called catastrophic quenching of the {alpha} effect in astrophysical applications. A stronger field reversal can be obtained if there is also a significant kinetic {alpha} effect. Application to the reversed field pinch in plasma confinement devices is discussed.

  6. Prospects for measuring the fuel ion ratio in burning ITER plasmas using a DT neutron emission spectrometer

    SciTech Connect (OSTI)

    Hellesen, C.; Skiba, M., E-mail: mateusz.skiba@physics.uu.se; Dzysiuk, N.; Weiszflog, M.; Hjalmarsson, A.; Ericsson, G.; Conroy, S.; Andersson-Sundén, E.; Eriksson, J.; Binda, F. [Department of Physics and Astronomy, Uppsala University, Uppsala (EURATOM-VR Association), SE-75120 Uppsala (Sweden)

    2014-11-15

    The fuel ion ratio n{sub t}/n{sub d} is an essential parameter for plasma control in fusion reactor relevant applications, since maximum fusion power is attained when equal amounts of tritium (T) and deuterium (D) are present in the plasma, i.e., n{sub t}/n{sub d} = 1.0. For neutral beam heated plasmas, this parameter can be measured using a single neutron spectrometer, as has been shown for tritium concentrations up to 90%, using data obtained with the MPR (Magnetic Proton Recoil) spectrometer during a DT experimental campaign at the Joint European Torus in 1997. In this paper, we evaluate the demands that a DT spectrometer has to fulfill to be able to determine n{sub t}/n{sub d} with a relative error below 20%, as is required for such measurements at ITER. The assessment shows that a back-scattering time-of-flight design is a promising concept for spectroscopy of 14 MeV DT emission neutrons.

  7. Fusion alpha-particle losses in a high-beta rippled tokamak

    SciTech Connect (OSTI)

    Bunno, M.; Nakamura, Y. [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Suzuki, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)] [National Institute for Fusion Science, Toki 509-5292 (Japan); Shinohara, K.; Matsunaga, G. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Tani, K. [Nippon Advanced Technology, Naka, Ibaraki 311-0102 (Japan)] [Nippon Advanced Technology, Naka, Ibaraki 311-0102 (Japan)

    2013-08-15

    In tokamak plasmas, the confinement of energetic ions depends on the magnetic field structure. If the plasma pressure is finite, the equilibrium current (i.e., the Pfirsch-Schlüter current and diamagnetic current) flows in the plasma to maintain the magnetohydrodynamic (MHD) equilibrium. These plasma currents generate poloidal and toroidal magnetic field and alter the field structure. Moreover, if we consider the non-axisymmetry of magnetic field structures such as toroidal field (TF) ripples, the non-axisymmetric component of the equilibrium current can alter TF ripples themselves. When the plasma beta becomes high, the changes in the field structure due to the equilibrium current might affect the confinement of energetic ions significantly. We intend to clarify how these currents alter the field structure and affect the confinement of alpha particles in high-beta plasma. The MHD equilibrium is calculated using VMEC and the orbits of fusion alpha particles are followed by using the fully three-dimensional magnetic field orbit-following Monte Carlo code. In relatively low-beta plasma (e.g., the volume-averaged beta value ?2%), the changes in the magnetic field component due to the plasma current negligibly affect the confinement of alpha particles except for the Shafranov shift effect. However, for ?3%, the diamagnetic effect reduces the magnetic field strength and significantly increases alpha-particle losses. In these high-beta cases, the non-axisymmetric field component generated by the equilibrium current also increases these losses, but not as effectively as compared to the diamagnetic effect.

  8. Primary beam steering due to field leakage from superconducting SHMS magnets

    SciTech Connect (OSTI)

    Moore, M. H. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States); Waidyawansa, B. P. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Covrig, S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Carlini, R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Benesch, J. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2014-11-01

    Simulations of the magnetic fields from the Super High Momentum Spectrometer in Hall C at Thomas Jefferson National Accelerator Facility show significant field leakage into the region of the primary beam line between the target and the beam dump. Without mitigation, these remnant fields will steer the unscattered beam enough to limit beam operations at small scattering angles. Presented here are magnetic field simulations of the spectrometer magnets and a solution using optimal placement of a minimal amount of shielding iron around the beam line.

  9. Primary Beam Steering Due to Field Leakage from Superconducting SHMS Magnets

    E-Print Network [OSTI]

    Michael H. Moore; Buddhini P. Waidyawansa; Silviu Covrig; Roger Carlini; Jay Benesch

    2014-08-26

    Simulations of the magnetic fields from the Super High Momentum Spectrometer in Hall C at Thomas Jefferson National Accelerator Facility show significant field leakage into the region of the primary beam line between the target and the beam dump. Without mitigation, these remnant fields will steer the unscattered beam enough to limit beam operations at small scattering angles. Presented here are magnetic field simulations of the spectrometer magnets and a solution using optimal placement of a minimal amount of shielding iron around the beam line.

  10. Primary beam steering due to field leakage from superconducting SHMS magnets

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

    Moore, Michael H.; Old Dominion Univ., Norfolk, VA; Waidyawansa, Buddhini P.; Covrig, Silviu; Carlini, Roger; Benesch, Jay

    2014-11-05

    In this study, simulations of the magnetic fields from the Super High Momentum Spectrometer in Hall C at Thomas Jefferson National Accelerator Facility show significant field leakage into the region of the primary beam line between the target and the beam dump. Without mitigation, these remnant fields will steer the unscattered beam enough to limit beam operations at small scattering angles. Presented here are magnetic field simulations of the spectrometer magnets and a solution using optimal placement of a minimal amount of shielding iron around the beam line.

  11. Local Varying-Alpha Theories

    E-Print Network [OSTI]

    John D. Barrow; Joao Magueijo

    2015-01-30

    In a recent paper we demonstrated how the simplest model for varying alpha may be interpreted as the effect of a dielectric material, generalized to be consistent with Lorentz invariance. Unlike normal dielectrics, such a medium cannot change the speed of light, and its dynamics obey a Klein-Gordon equation. This work immediately suggests an extension of the standard theory, even if we require compliance with Lorentz invariance. Instead of a wave equation, the dynamics may satisfy a local algebraic relation involving the permittivity and the properties of the electromagnetic field, in analogy with more conventional dielectric (but still preserving Lorentz invariance). We develop the formalism for such theories and investigate some phenomenological implications. The problem of the divergence of the classical self-energy can be solved, or at least softened, in this framework. Some interesting new cosmological solutions for the very early universe are found, including the possibility of a bounce, inflation and expansion with a loitering phase, all of which are induced by early variations in alpha.

  12. Characterization of polyxylylenes with solid state {sup 13}C nuclear magnetic resonance spectroscopy

    SciTech Connect (OSTI)

    Schneider, D.A.; Loy, D.A.; Assink, R.A. [Sandia National Labs., Albuquerque, NM (United States)] [and others

    1996-10-01

    Polyxylylenes are an important class of thermoplastics that are readily prepared by thermolysis of [2.2]paracyclophane or xylene precursors to afford xylylene monomers that condense and polymerize on solid surfaces to give polymer films. As most polyxylylenes are insoluble due to a high degree of crystallinity, characterization by solid state nuclear magnetic resonance spectroscopic techniques is necessary. In this paper we describe the preparation of polyxylylene, poly-2-ethylxylylene, poly-2-chloroxylylene, poly-2, 3-dichloroxylylene, and poly({alpha}, {alpha}, {alpha}{prime}, {alpha}{prime}-tetrafluoroxylylene) and their characterization using solid state {sup 13}C Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (CP MAS NMR) spectroscopy.

  13. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

    Becker, Gregory K. (Idaho Falls, ID); Martz, Dowell E. (Grand Junction, CO)

    1989-01-01

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

  14. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

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

    1988-06-27

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

  15. SHOE V.1.5 ALPHA

    Energy Science and Technology Software Center (OSTI)

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

  16. SIEMENS ADVANCED QUANTRA FTICR MASS SPECTROMETER FOR ULTRA HIGH RESOLUTION AT LOW MASS

    SciTech Connect (OSTI)

    Spencer, W; Laura Tovo, L

    2008-07-08

    The Siemens Advanced Quantra Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer was evaluated as an alternative instrument to large double focusing mass spectrometers for gas analysis. High resolution mass spectrometers capable of resolving the common mass isomers of the hydrogen isotopes are used to provide data for accurate loading of reservoirs and to monitor separation of tritium, deuterium, and helium. Conventional double focusing magnetic sector instruments have a resolution that is limited to about 5000. The Siemens FTICR instrument achieves resolution beyond 400,000 and could possibly resolve the tritium ion from the helium-3 ion, which differ by the weight of an electron, 0.00549 amu. Working with Y-12 and LANL, SRNL requested Siemens to modify their commercial Quantra system for low mass analysis. To achieve the required performance, Siemens had to increase the available waveform operating frequency from 5 MHz to 40 MHz and completely redesign the control electronics and software. However, they were able to use the previous ion trap, magnet, passive pump, and piezo-electric pulsed inlet valve design. NNSA invested $1M in this project and acquired four systems, two for Y-12 and one each for SRNL and LANL. Siemens claimed a $10M investment in the Quantra systems. The new Siemens Advanced Quantra demonstrated phenomenal resolution in the low mass range. Resolution greater than 400,000 was achieved for mass 2. The new spectrometer had a useful working mass range to 500 Daltons. However, experiments found that a continuous single scan from low mass to high was not possible. Two useful working ranges were established covering masses 1 to 6 and masses 12 to 500 for our studies. A compromise performance condition enabled masses 1 to 45 to be surveyed. The instrument was found to have a dynamic range of about three orders of magnitude and quantitative analysis is expected to be limited to around 5 percent without using complex fitting algorithms. Analysis of low concentration ions, at the ppm level, required a separate analysis using ion ejection techniques. Chemical ionization due to the formation of the MH{sup +} ion or MD{sup +} increased the complexity of the spectra compared to magnetic sector mass spectra and formation of the protonated or deuterated complex was a dynamic function of the trap ion concentration. This made quantitative measurement more of a challenge. However, the resolution of the instrument was far superior to any other mass spectrometry technique that has been applied to the analysis of the hydrogen isotopes. The piezo-electric picoliter injection device offers a new way of submitting small quantities of atmospheric pressure sample gas for analysis. The new software had many improvements over the previous version but significant flaws in the beta codes remain that make the prototype units less than ideal. The instrument is a promising new technology that experience will likely improve. Unfortunately, Siemens has concluded that the technology will not be a commercial success and has decided to stop producing this product.

  17. Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane

    E-Print Network [OSTI]

    Texas at Austin, University of

    Photonic Crystal Slot Waveguide Spectrometer for Detection of Methane 1 Funded by Environmental. of Electrical and Computer Engineering, University of Texas, Austin #12;Motivation No other chip based optical Similar to: Doping of Semiconductor 3 #12;4 Photonic Crystal Bio-Chemical Sensors Loncar et al, Appl. Phys

  18. Pair spectrometer hodoscope for Hall D at Jefferson Lab

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

    Barbosa, Fernando J.; Hutton, Charles L.; Sitnikov, Alexandre; Somov, Alexander S.; Somov, S.; Tolstukhin, Ivan

    2015-09-21

    We present the design of the pair spectrometer hodoscope fabricated at Jefferson Lab and installed in the experimental Hall D. The hodoscope consists of thin scintillator tiles; the light from each tile is collected using wave-length shifting fibers and detected using a Hamamatsu silicon photomultiplier. Light collection was measured using relativistic electrons produced in the tagger area of the experimental Hall B.

  19. Modulated optical solid-state spectrometer applications in plasma diagnostics

    E-Print Network [OSTI]

    Howard, John

    Modulated optical solid-state spectrometer applications in plasma diagnostics John Howard Plasma A new electro-optically modulated optical solid-state MOSS interferometer has been constructed for the measurement of the low order spectral moments of line emission from optically thin radiant media

  20. GBT memo No. 292 Specifications for the GBT spectrometer

    E-Print Network [OSTI]

    Groppi, Christopher

    splitter Power 1PPS S/W sig o/p S/W sig i/p 100M/1G E switch To ROACH boards ROACH (Switching master technology. 1 Introduction A new spectrometer is being designed for the Green Bank Telescope (GBT polarizations (linear or circular) of a receiver. For many observations we need only the self spectral powers

  1. Binding Energies of the Alpha Particle and the A=3 Isobars from a Theoretical Geometric Model

    E-Print Network [OSTI]

    Gustavo R. Gonzalez-Martin

    2008-05-03

    We assume a triple geometric structure for the electromagnetic nuclear interaction. This nuclear electromagnetism is used to calculate the binding energies of the alpha particle and the A=3 isobar nuclides. The approximation for the resultant wave equation which lead to the deuteron binding energy from the modified Mathieu equation for the radial eigenvalue equation also establishes proton-electron-proton magnetic bonds in these nuclides and determines their binding energies. Completely theoretical calculations give 28.5 Mev., 7.64 Mev. and 8.42 Mev. for the binding energies of the alpha particle, the helium 3 isotope and tritium respectively. These values admit correction factors due to the approximations made.

  2. Scaling studies with the dual crystal spectrometer at the OMEGA-EP laser facility

    SciTech Connect (OSTI)

    Szabo, C. I.; Feldman, U.; Workman, J.; Flippo, K.; Seely, J. F.; Hudson, L. T.; Henins, A.

    2010-10-15

    The dual crystal spectrometer (DCS) is an approved diagnostic at the OMEGA and the OMEGA-EP laser facilities for the measurement of high energy x-rays in the 11-90 keV energy range, e.g., for verification of the x-ray spectrum of backlighter targets of point projection radiography experiments. DCS has two cylindrically bent transmission crystal channels with image plate detectors at distances behind the crystals close to the size of the respective Rowland circle diameters taking advantage of the focusing effect of the cylindrically bent geometry. DCS, with a source to crystal distance of 1.2 m, provides the required energy dispersion for simultaneous detection of x-rays in a low energy channel (11-45 keV) and a high-energy channel (19-90 keV). A scaling study is described for varied pulse length with unchanged laser conditions (energy, focusing). The study shows that the K{alpha} line intensity is not strongly dependent on the length of the laser pulse.

  3. Johann Spectrometer for High Resolution X-ray Spectroscopy

    SciTech Connect (OSTI)

    Machek, Pavel; Froeba, Michael; Welter, Edmund; Caliebe, Wolfgang; Brueggmann, Ulf; Draeger, Guenter

    2007-01-19

    A newly designed vacuum Johann spectrometer with a large focusing analyzer crystal for inelastic x-ray scattering and high resolution fluorescence spectroscopy has been installed at the DORIS III storage ring. Spherically bent crystals with a maximum diameter of 125 mm, and cylindrically bent crystals are employed as dispersive optical elements. Standard radius of curvature of the crystals is 1000 mm, however, the design of the mechanical components also facilitates measurements with smaller and larger bending radii. Up to four crystals are mounted on a revolving crystal changer which enables crystal changes without breaking the vacuum. The spectrometer works at fixed Bragg angle. It is preferably designed for the measurements in non-scanning mode with a broad beam spot, and offers a large flexibility to set the sample to the optimum position inside the Rowland circle. A deep depletion CCD camera is employed as a position sensitive detector to collect the energy-analyzed photons on the circumference of the Rowland circle. The vacuum in the spectrometer tank is typically 10-6 mbar. The sample chamber is separated from the tank either by 25 {mu}m thick Kapton windows, which allows samples to be measured under ambient conditions, or by two gate valves. The spectrometer is currently installed at wiggler beamline W1 whose working range is 4-10.5 keV with typical flux at the sample of 5x1010photons/s/mm2. The capabilities of the spectrometer are illustrated by resonant inelastic experiments on 3d transition metals and rare earth compounds, and by chemical shift measurements on chromium compounds.

  4. Results from the NSTX X-ray Crystal Spectrometer

    SciTech Connect (OSTI)

    M. Bitter; K. Hill; L. Roquemore; P. Beiersdorfer; D. Thorn; Ming Feng Gu

    2003-01-14

    A high-resolution X-ray crystal spectrometer has recently been installed at the National Spherical Torus Experiment to record the satellite spectra of helium-like argon, ArXVII, in the wavelength range from 3.94 to 4.00 {angstrom} for measurements of ion and electron temperatures, and measurements of the ionization equilibrium of argon, which is of interest for studies of ion transport. The instrument presently consists of a spherically bent quartz crystal and a conventional one-dimensional position-sensitive multi-wire proportional counter, but it will soon be upgraded to a new type of X-ray imaging crystal spectrometer by the installation of a large size (10 cm x 30 cm) two-dimensional position-sensitive detector that will allow us to obtain temporally and spatially resolved spectra from an 80 cm high cross-section of the plasma. In its present configuration, the spectrometer has been optimized for high throughput so that it is possible to record spectra with small statistical errors with a time resolution of 10 ms by adding only small, nonperturbing amounts of argon to the plasma. The spectrometer is most valuable for measurements of the ion temperature in the absence of a neutral beam in ohmically heated and radio-frequency heated discharges, when charge exchange recombination spectroscopy does not function. Electron temperature measurements from the satellite-to-resonance line ratios have been important for a quantitative comparison with (and verification of) the Thomson scattering data. The paper will describe the instrumental details of the present and future spectrometer configurations, and present recent experimental results.

  5. alpha(s) Determinations from Jets and Scaling Violations at HERA

    E-Print Network [OSTI]

    Thomas Kluge

    2006-10-13

    A review is given on recent alpha(s) determinations from the H1 and ZEUS Collaborations. These are based on measurements of jet cross sections, event shape variables, as well as on the observed scaling violation of the structure function F_2. A HERA average on alpha(s)(m_Z) is presented, in comparison with world mean values.

  6. Evidence for an alpha cluster condensed state in 16O(alpha,alpha') at 400 MeV

    E-Print Network [OSTI]

    T. Wakasa; E. Ihara; K. Fujita; Y. Funaki; K. Hatanaka; H. Horiuchi; M. Itoh; J. Kamiya; G. Ropke; H. Sakaguchi; N. Sakamoto; Y. Sakemi; P. Schuck; Y. Shimizu; M. Takashina; S. Terashima; A. Tohsaki; M. Uchida; H. P. Yoshida; M. Yosoi

    2006-11-13

    Inelastic $\\alpha$ scattering on 16O is studied at 400 MeV by using an ice target. Near the 4-alpha breakup threshold of 14.4 MeV, a broad peak is observed at an excitation energy of 13.6+/-0.2 MeV with a width of 0.6+/-0.2 MeV. The spin-parity is estimated to be 0+ from the momentum-transfer dependence. The observed width is significantly larger than those of the neighboring 0+ states indicating a state with a well-developed alpha cluster structure. The magnitude of the cross section is sensitive to the density distribution of the constituent alpha clusters. The observed cross section is consistent with the theoretical prediction for the alpha cluster condensed state characterized by its dilute density distribution with a large root-mean-square radius of about 4.3 fm.

  7. Miniature, high-speed imaging transform spectrometers and advanced sampling algorithms

    E-Print Network [OSTI]

    Chen, Yi, Ph. D. Massachusetts Institute of Technology

    2015-01-01

    This thesis describes the development of miniature imaging Fourier transform spectrometers and irregular sampling techniques. An imaging spectrometer is a device that takes a series of images that include information from ...

  8. Upgrade of the neon soft X-ray spectrometer for Alcator C-Mod

    E-Print Network [OSTI]

    Podpaly, Yuri Anatoly

    2007-01-01

    In order to study plasma rotation, temperature, and impurity density, a Neon Soft X-ray Spectrometer (NeSoXs) was installed on the Alcator C-Mod tokamak. This spectrometer used a spherically bent mica crystal as the ...

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

    E-Print Network [OSTI]

    McElmurry, Blake Anthony

    2009-05-15

    The development of a co-axially configured submillimeter spectrometer is reported. The spectrometer has been constructed to observe molecular complexes that exhibit non-covalent interactions with energies much less than ...

  10. A new spectrometer design for the x-ray spectroscopy of laser...

    Office of Scientific and Technical Information (OSTI)

    A new spectrometer design for the x-ray spectroscopy of laser-produced plasmas with high (sub-ns) time resolution Citation Details In-Document Search Title: A new spectrometer...

  11. High-alpha space trucks

    SciTech Connect (OSTI)

    Cook, L.M. [Ball Aerospace and Technology Corp. 1600 Commerce St. MS CO-9 Boulder, Colorado80301 (United States); Ball, J. [McDonnel Douglas Aerospace 5301 Bolsa Ave. MS 13-3 Huntington Beach, California92647 (United States)

    1997-01-01

    Vertically-landing Reusable Launch Vehicles (RLVs) are the best hope of building a true {open_quotes}Space Truck{close_quotes} with current technology. Because they do not require a low angle-of-attack (AOA, or alpha) horizontal landing, they can be designed to operate exclusively at very high angles-of-attack. This offers savings in vehicle dry weight and complexity, which can be traded for significantly heavier payload, more ascent velocity, or extra design margin. The price for abandoning low angle-of-attack flight is reduced crossrange. To quantify the potential weight reduction, a trade study was performed to determine the relationship between a vehicle{close_quote}s maximum crossrange (angle-of-attack) and it{close_quote}s dry weight (payload margin). At the study conclusion, three vertically-landing (VL) vehicles provided multiple points on a payload weight vs. maximum crossrange curve, showing significant payload increases as crossrange is sacrificed. This is primarily the result of being able to simplify the structure, fly a cooler entry trajectory, and be aerodynamically stable through the entire flight. This reduces subsystem requirements and complexity, enhancing reliability. Further benefits are realized in reduced landing propellant requirements and simplifying or eliminating the {open_quotes}rotation{close_quotes} maneuver. This paper also suggests unique operability solutions that adapt high-alpha vehicles to traditional high-crossrange missions such as the polar {open_quotes}once-around{close_quotes} flight, and proposes a small scale drop-test program to prove the subsonic and landing portion of the flight envelope. {copyright} {ital 1997 American Institute of Physics.}

  12. Effects of alpha particles on the angular momentum loss from the Sun

    E-Print Network [OSTI]

    Bo Li; Xing Li

    2006-06-07

    The classic Weber-Davis model of the solar wind is reconsidered by incorporating alpha particles and by allowing the solar wind to flow out of the equatorial plane in an axisymmetrical configuration. In the ion momentum equations of the solar wind, the ion gyro-frequency is many orders of magnitude higher than any other frequency. This requires that the difference between proton and alpha velocity vectors be aligned with the background magnetic field. With the aid of this alignment condition, the governing equations of the multi-fluid solar wind are derived from the standard transport equations. The governing equations are numerically solved along a prescribed meridional magnetic field line located at colatitude $70^\\circ$ at 1AU and a steady state fast solar wind solution is found. A general analysis concludes, in agreement with the Weber-Davis model, that the magnetic field helps the coronal plasma to achieve an effective corotation out to the Alfv\\'enic radius, where the poloidal Alfv\\'enic Mach number $M_T$ equals unity ($M_T$ is defined by equation (\\ref{eq:mach})). The model computations show that, magnetic stresses predominate the angular momentum loss of the Sun. For the fast wind considered, the proton contribution to the angular momentum loss, which can be larger than the magnetic one, is almost completely canceled by the alpha particles that develop an azimuthal speed in the direction opposite to the solar rotation. The Poynting flux associated with the azimuthal components is negligible in the energy budget. However, the solar rotation can play some role in reducing the relative speed between alpha particles and protons for low latitude fast solar wind streams in interplanetary space.

  13. THE MECHANICAL AND SHIELDING DESIGN OF A PORTABLE SPECTROMETER AND BEAM DUMP ASSEMBLY AT BNLS ACCELERATOR TEST FACILITY.

    SciTech Connect (OSTI)

    HU,J.P.; CASEY,W.R.; HARDER,D.A.; PJEROV,S.; RAKOWSKY,G.; SKARITKA,J.R.

    2002-09-05

    A portable assembly containing a vertical-bend dipole magnet has been designed and installed immediately down-beam of the Compton electron-laser interaction chamber on beamline 1 of the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). The water-cooled magnet designed with field strength of up to 0.7 Tesla will be used as a spectrometer in the Thompson scattering and vacuum acceleration experiments, where field-dependent electron scattering, beam focusing and energy spread will be analyzed. This magnet will deflect the ATF's 60 MeV electron-beam 90{sup o} downward, as a vertical beam dump for the Compton scattering experiment. The dipole magnet assembly is portable, and can be relocated to other beamlines at the ATF or other accelerator facilities to be used as a spectrometer or a beam dump. The mechanical and shielding calculations are presented in this paper. The structural rigidity and stability of the assembly were studied. A square lead shield surrounding the assembly's Faraday Cup was designed to attenuate the radiation emerging from the 1 inch-copper beam stop. All photons produced were assumed to be sufficiently energetic to generate photoneutrons. A safety evaluation of groundwater tritium contamination due to the thermal neutron capturing by the deuterium in water was performed, using updated Monte Carlo neutron-photon coupled transport code (MCNP). High-energy neutron spallation, which is a potential source to directly generate radioactive tritium and sodium-22 in soil, was conservatively assessed in verifying personal and environmental safety.

  14. Determination of alpha_s from the QCD static energy: an update

    E-Print Network [OSTI]

    Alexei Bazavov; Nora Brambilla; Xavier Garcia i Tormo; Peter Petreczky; Joan Soto; Antonio Vairo

    2014-11-04

    We present an update of our determination of the strong coupling alpha_s from the quantum chromodynamics static energy. This updated analysis includes new lattice data, at smaller lattice spacings and reaching shorter distances, the use of better suited perturbative expressions to compare with data in a wider distance range, and a comprehensive and detailed estimate of the error sources that contribute to the uncertainty of the final result. Our updated value for alpha_s at the Z-mass scale, M_Z, is alpha_s(M_Z)=0.1166^{+0.0012}_{-0.0008}, which supersedes our previous result.

  15. High-precision CO2 isotopologue spectrometer with a difference-frequency-generation laser source

    E-Print Network [OSTI]

    High-precision CO2 isotopologue spectrometer with a difference-frequency-generation laser source A precision laser spectrometer for the detection of CO2 isotopes is reported. The spectrometer measures the fundamental absorption signatures of 13 C and 12 C isotopes in CO2 at 4.32 m using a tunable mid-IR laser

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

    SciTech Connect (OSTI)

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

    1998-06-29

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

  17. Magnets & Magnet Condensed Matter Science

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Sights from around the Magnet Lab in 2010. On the cover MAGNETS & MAGNET MATERIALS Engineering materials in Mesoporous Silica SBA-15 31 YBCO Pancake Wound Test Coil for 32-T Magnet Development 32 Strong Vortex Pinning from Marine Cyanobacteria 37 Heavy Petroleum Composition 2. Progression of the Boduszynski Model

  18. Accuracy evaluation of a Compton X-ray spectrometer with bremsstrahlung X-rays generated by a 6 MeV electron bunch

    SciTech Connect (OSTI)

    Kojima, Sadaoki Arikawa, Yasunobu; Zhang, Zhe; Ikenouchi, Takahito; Morace, Alessio; Nagai, Takahiro; Abe, Yuki; Sakata, Shouhei; Inoue, Hiroaki; Utsugi, Masaru; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke; Azechi, Hiroshi; Nishimura, Yasuhiko; Togawa, Hiromi; Ozaki, Tetsuo; Kato, Ryukou

    2014-11-15

    A Compton-scattering-based X-ray spectrometer is developed to obtain the energy distribution of fast electrons produced by intense laser and matter interactions. Bremsstrahlung X-rays generated by fast electrons in a material are used to measure fast electrons’ energy distribution in matter. In the Compton X-ray spectrometer, X-rays are converted into recoil electrons by Compton scattering in a converter made from fused silica glass, and a magnet-based electron energy analyzer is used to measure the energy distribution of the electrons that recoil in the direction of the incident X-rays. The spectrum of the incident X-rays is reconstructed from the energy distribution of the recoil electrons. The accuracy of this spectrometer is evaluated using a quasi-monoenergetic 6 MeV electron bunch that emanates from a linear accelerator. An electron bunch is injected into a 1.5 mm thick tungsten plate to produce bremsstrahlung X-rays. The spectrum of these bremsstrahlung X-rays is obtained in the range from 1 to 9 MeV. The energy of the electrons in the bunch is estimated using a Monte Carlo simulation of particle-matter interactions. The result shows that the spectrometer's energy accuracy is ±0.5 MeV for 6.0 MeV electrons.

  19. Multi-Collector Inductively Coupled Plasma Mass Spectrometer – Operational Performance Report

    SciTech Connect (OSTI)

    Matthew Watrous; Anthony Appelhans; Robert Hague; John Olson; Tracy Houghton

    2013-06-01

    The INL made an assessment of the commercially available inductively coupled plasma mass spectrometers (ICPMS) for actinide analysis; emphasizing low detection limits for plutonium. INL scientists subsequently determined if plutonium was present on a swipe, at a 10 million atom decision level. This report describes the evaluation of ICPMS instruments and the operational testing of a new process for the dissolution, separation and analysis via ICPMS of swipes for plutonium and uranium. The swipe dissolution, plutonium and uranium isolation, separation and purification are wet chemistry methods following established procedures. The ICPMS is a commercially available multi-collector magnetic sector mass spectrometer that utilizes five ion counting detectors operating simultaneously. The instrument includes a sample introduction system allowing for sample volumes of < 1 mL to be reproducibly injected into the instrument with minimal waste of the sample solution, while maximizing the useable signal. The performance of the instrument was measured using SRM 996 (244Pu spike) at concentrations of 12 parts per quadrillion (ppq, fg/mL) and with SRM 4350B Columbia River Sediment samples spiked onto swipes at the 10 million atom level. The measured limit of detection (LOD, defined as 3s) for 239Pu is 310,000 atoms based upon the instrument blank data. The limit of quantification (LOQ defined as 10 s) for 239Pu is 105,000 atoms. The measured limit of detection for 239Pu from the SRM 4350B spiked onto a swipe was 2.7 million atoms with the limit of quantification being 9.0 million atoms.

  20. The 28th International Cosmic Ray Conference 1 The Performance of the AMS-02 TRD

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    in a vacuum chamber. 1. Introduction The Alpha Magnetic Spectrometer (AMS-02) [1] is an experiment which Magnetic Spectrometer (AMS-02) is an experiment which will be mounted on the International Space Station, Cambridge, MA, USA (2) Universit di Roma "La Sapienza", I.N.F.N. Sez.Roma1, Roma, Italy Abstract The Alpha

  1. Inverse time-of-flight spectrometer for beam plasma research

    SciTech Connect (OSTI)

    Yushkov, Yu. G., E-mail: yuyushkov@gmail.com; Zolotukhin, D. B.; Tyunkov, A. V. [Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050 (Russian Federation); Oks, E. M. [Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050 (Russian Federation); Institute of High Current Electronics SB RAS, 2/3, Akademichesky Ave., Tomsk 634055 (Russian Federation); Savkin, K. P. [Institute of High Current Electronics SB RAS, 2/3, Akademichesky Ave., Tomsk 634055 (Russian Federation)

    2014-08-15

    The paper describes the design and principle of operation of an inverse time-of-flight spectrometer for research in the plasma produced by an electron beam in the forevacuum pressure range (5–20 Pa). In the spectrometer, the deflecting plates as well as the drift tube and the primary ion beam measuring system are at high potential with respect to ground. This provides the possibility to measure the mass-charge constitution of the plasma created by a continuous electron beam with a current of up to 300 mA and electron energy of up to 20 keV at forevacuum pressures in the chamber placed at ground potential. Research results on the mass-charge state of the beam plasma are presented and analyzed.

  2. The Design and Construction of the MICE Spectrometer Solenoids

    SciTech Connect (OSTI)

    Wang, Bert; Wahrer, Bob; Taylor, Clyde; Xu, L.; Chen, J. Y.; Wang, M.; Juang, Tiki; Zisman, Michael S.; Virostek, Steve P.; Green, Michael A.

    2008-08-02

    The purpose of the MICE spectrometer solenoid is to provide a uniform field for a scintillating fiber tracker. The uniform field is produced by a long center coil and two short end coils. Together, they produce 4T field with a uniformity of better than 1% over a detector region of 1000 mm long and 300 mm in diameter. Throughout most of the detector region, the field uniformity is better than 0.3%. In addition to the uniform field coils, we have two match coils. These two coils can be independently adjusted to match uniform field region to the focusing coil field. The coil package length is 2544 mm. We present the spectrometer solenoid cold mass design, the powering and quench protection circuits, and the cryogenic cooling system based on using three cryocoolers with re-condensers.

  3. Focusing of millijoule picosecond K{sub a}lpha radiation from 100 TW laser-solid interaction

    SciTech Connect (OSTI)

    Levy, A.; Dorchies, F.; Audebert, P.; Chalupsky, J.; Hajkova, V.; Juha, L.; Vysin, L.; Kaempfer, T.; Uschmann, I.; Sinn, H.; Gaudin, J.

    2010-04-12

    A calibrated x-ray spectrometer was used to characterize an intense 4.5 keV K{sub a}lpha source. Generated from the interaction of 30 J-320 fs laser pulses focused on 25 mum thick Ti foils, the conversion efficiency into Ti K{sub a}lpha line is estimated to (9+-6)x10{sup -5}. Highly efficient collection, monochromatization and focusing were achieved using an ellipsoidally bent highly oriented pyrolytic graphite crystal. The measured 700 mum full width half maximum (FWHM) focal spot leads to a fluence of (3.0+-2.1) mJ/cm{sup 2} hence paving the way to the study of intense x-ray pulse interaction with matter as demonstrated by a first simple experiment.

  4. Polarimeters and Energy Spectrometers for the ILC Beam Delivery System

    SciTech Connect (OSTI)

    Boogert, S.; /Royal Holloway, U. of London; Hildreth, M.; /Notre Dame U.; Kafer, D.; List, J.; Monig, K.; /DESY; Moffeit, K.C.; /SLAC; Moortgat-Pick, G.; /Durham U., IPPP; Riemann, S.; Schreiber, H.J.; Schuler, P.; /DESY; Torrence, E.; /Oregon U.; Woods, M.; /SLAC

    2009-02-24

    This article gives an overview of current plans and issues for polarimeters and energy spectrometers in the Beam Delivery System of the ILC. It is meant to serve as a useful reference for the Detector Letter of Intent documents currently being prepared. Concepts for high precision polarization and energy measurements exist. These concepts have resulted in detailed system layouts that are included in the RDR description for the Beam Delivery System. The RDR includes both upstream and downstream polarimeters and energy spectrometers for both beams. This provides needed complementarity and redundancy for achieving the precision required, with adequate control and demonstration of systematic errors. The BDS polarimeters and energy spectrometers need to be a joint effort of the ILC BDS team and the Detector collaborations, with collaboration members responsible for the performance and accuracy of the measurements. Details for this collaboration and assigning of responsibilities remain to be worked out. There is also a demonstrated need for Detector physicists to play an active role in the design and evaluation of accelerator components that impact beam polarization and beam energy capabilities, including the polarized source and spin rotator systems. A workshop was held in 2008 on ILC Polarization and Energy measurements, which resulted in a set of recommendations for the ILC design and operation. Additional input and action is needed on these from the Detector collaborations, the Research Director and the GDE. Work is continuing during the ILC engineering design phase to further optimize the polarimeter and energy spectrometer concepts and fully implement them in the ILC. This includes consideration for alternative methods, detailed design and cost estimates, and prototype and test beam activities.

  5. Extracting source parameters from beam monitors on a chopper spectrometer

    SciTech Connect (OSTI)

    Abernathy, Douglas L [ORNL; Niedziela, Jennifer L [ORNL; Stone, Matthew B [ORNL

    2015-01-01

    The intensity distributions of beam monitors in direct-geometry time-of-flight neutron spectrometers provide important information about the instrument resolution. For short-pulse spallation neutron sources in particular, the asymmetry of the source pulse may be extracted and compared to Monte Carlo source simulations. An explicit formula using a Gaussian-convolved Ikeda-Carpenter distribution is given and compared to data from the ARCS instrument at the Spallation Neutron Source.

  6. Polarization Measurements in Photoproduction with CEBAF Large Acceptance Spectrometer

    SciTech Connect (OSTI)

    E. Pasyuk

    2010-05-01

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

  7. Time-of-flight direct recoil ion scattering spectrometer

    DOE Patents [OSTI]

    Krauss, A.R.; Gruen, D.M.; Lamich, G.J.

    1994-09-13

    A time-of-flight direct recoil and ion scattering spectrometer beam line is disclosed. The beam line includes an ion source which injects ions into pulse deflection regions and separated by a drift space. A final optics stage includes an ion lens and deflection plate assembly. The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions. 23 figs.

  8. Calibrations of alpha Cen A & B

    E-Print Network [OSTI]

    Morel, P; Lebreton, Y; Thévenin, F; Berthomieu, G

    2000-01-01

    Detailed evolutionary models of the visual binary alpha Centauri, including pre main-sequence evolution, have been performed using the masses recently determined by Pourbaix et al. (1999). Models have been constructed using the CEFF equation of state, OPAL opacities, NACRE thermonuclear reaction rates and microscopic diffusion. A chi^2-minimization is performed to derive the most reliable set of modeling parameters wp={t_alpha Cen, Yi, [Fe/H]i, alpha A, alpha B}, where t alpha Cen is the age of the system, Yi the initial helium content, [Fe/H]i the initial metallicity and, alpha A and alpha B the convection parameters of the two components. Using the basic Bohm-Vitense (1958) mixing-length theory of convection, we derive wp BV={2710 Myr, 0.284,0.257, 1.53, 1.57}. We obtain a noticeably smaller age than estimated previously, in agreement with Pourbaix et al. (1999), mainly because of the larger masses. If convective core overshoot is considered we get wp ov={3530 Myr, 0.279,0.264,1.64,1.66}. The use of Canuto ...

  9. $\\alpha_s$ from the updated ALEPH data for hadronic $\\tau$ decays

    E-Print Network [OSTI]

    Boito, Diogo; Maltman, Kim; Osborne, James; Peris, Santiago

    2015-01-01

    We extract the strong coupling $\\alpha_s(m_\\tau^2)$ from the recently updated ALEPH non-strange spectral functions obtained from hadronic $\\tau$ decays. We apply a self-consistent analysis method, first tested in the analysis of OPAL data, to extract $\\alpha_s(m_\\tau^2)$ and non-perturbative contributions. The analysis yields $\\alpha_s^{\\rm FO}(m_\\tau^2)=0.296\\pm0.010 $, using Fixed Order Perturbation Theory (FOPT), and $\\alpha^{\\rm CI}_s(m_\\tau^2)= 0.310\\pm0.014$, using Contour Improved Perturbation Theory (CIPT). The weighted average of these results with those previously obtained from OPAL data give $\\alpha_s^{\\rm FO}(m_\\tau^2)=0.303\\pm 0.009$ and $\\alpha_s^{\\rm CI}(m_\\tau^2)=0.319\\pm 0.012$, which gives, after evolution to the $Z$ boson mass scale, $\\alpha^{\\rm FO}_s(m_Z^2)=0.1165\\pm0.0012 $ and $\\alpha_s^{\\rm CI}(m_Z^2)=0.1185\\pm0.0015 $, respectively. We observe that non-perturbative effects limit the accuracy with which $\\alpha_s$ can be extracted from $\\tau$ decay data.

  10. Progress on Superconducting Magnets for the MICE Cooling Channel

    SciTech Connect (OSTI)

    Green, Michael A; Virostek, Steve P.; Li, Derun; Zisman, Michael S.; Wang, Li; Pan, Heng; Wu, Hong; Guo, XingLong; Xu, FengYu; Liu, X. K.; Zheng, S. X.; Bradshaw, Thomas; Baynham, Elwyn; Cobb, John; Lau, Wing; Lau, Peter; Yang, Stephanie Q.

    2009-09-09

    The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of three types of superconducting solenoids; the spectrometer solenoids, the coupling solenoids and the focusing solenoids. The three types of magnets are being fabricated in he United States, China, and the United Kingdom respectively. The spectrometer magnets are used to analyze the muon beam before and after muon cooling. The coupling magnets couple the focusing sections and keep the muon beam contained within the iris of the RF cavities that re used to recover the muon momentum lost during ionization cooling. The focusing magnets focus the muon beam in the center of a liquid hydrogen absorber. The first of the cooling channel magnets will be operational in MICE in the spring of 2010.

  11. Highly Reproducible Laser Beam Scanning Device for an Internal Source Laser Desorption Microprobe Fourier Transform Mass Spectrometer

    SciTech Connect (OSTI)

    Scott, Jill Rennee; Tremblay, Paul Leland

    2002-03-01

    Traditionally, mass spectrometry has relied on manipulating the sample target to provide scanning capabilities for laser desorption microprobes. This has been problematic for an internal source laser desorption Fourier transform mass spectrometer (LD-FTMS) because of the high magnetic field (7 Tesla) and geometric constraints of the superconducting magnet bore. To overcome these limitations, we have implemented a unique external laser scanning mechanism for an internal source LD-FTMS. This mechanism provides adjustable resolution enhancement so that the spatial resolution at the target is not limited to that of the stepper motors at the light source (~5 µm/step). The spatial resolution is now limited by the practical optical diffraction limit of the final focusing lens. The scanning mechanism employs a virtual source that is wavelength independent up to the final focusing lens, which can be controlled remotely to account for focal length dependence on wavelength. A binary index provides an automatic alignment feature. The virtual source is located ~9 ft from the sample; therefore, it is completely outside of the vacuum system and beyond the 50 G line of the fringing magnetic field. To eliminate reproducibility problems associated with vacuum pump vibrations, we have taken advantage of the magnetic field inherent to the FTMS to utilize Lenz's law for vibrational dampening. The LD-FTMS microprobe has exceptional reproducibility, which enables successive mapping sequences for depth-profiling studies.

  12. Magnetoelastic Coupling and Symmetry Breaking in the Frustrated Antiferromagnet {alpha}-NaMnO{sub 2}

    SciTech Connect (OSTI)

    Giot, Maud; Chapon, Laurent C.; Radaelli, Paolo G.; Androulakis, John; Lappas, Alexandros; Green, Mark A.

    2007-12-14

    The magnetic and crystal structures of the {alpha}-NaMnO{sub 2} have been determined by high-resolution neutron powder diffraction. The system maps out a frustrated triangular spin lattice with anisotropic interactions that displays two-dimensional spin correlations below 200 K. Magnetic frustration is lifted through magneto-elastic coupling, evidenced by strong anisotropic broadening of the diffraction profiles at high temperature and ultimately by a structural phase transition at 45 K. In this low-temperature regime a three-dimensional antiferromagnetic state is observed with a propagation vector k=((1/2),(1/2),0)

  13. Superconducting magnets

    SciTech Connect (OSTI)

    Not Available

    1994-08-01

    This report discusses the following topics on superconducting magnets: D19B and -C: The next steps for a record-setting magnet; D20: The push beyond 10 T: Beyond D20: Speculations on the 16-T regime; other advanced magnets for accelerators; spinoff applications; APC materials development; cable and cabling-machine development; and high-{Tc} superconductor at low temperature.

  14. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    SciTech Connect (OSTI)

    FISHER,R.K

    2004-04-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  15. Approaches to confined alpha diagnostics on ITER

    SciTech Connect (OSTI)

    Fisher, R.K. [General Atomics, PO Box 85608, San Diego, California 92186-5608 (United States)

    2004-10-01

    Three approaches to obtain information on the confined fast alphas in the International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 {mu}m per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  16. Nuclear diagnostic for fast alpha particles

    DOE Patents [OSTI]

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

    1983-11-23

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

  17. Monte-Carlo simulation of noise in hard X-ray Transmission Crystal Spectrometers: Identification of contributors to the background noise and shielding optimization

    SciTech Connect (OSTI)

    Thfoin, I. Reverdin, C.; Duval, A.; Leboeuf, X.; Lecherbourg, L.; Rossé, B.; Hulin, S.; Batani, D.; Santos, J. J.; Vaisseau, X.; Fourment, C.; Giuffrida, L.; Szabo, C. I.; Bastiani-Ceccotti, S.; Brambrink, E.; Koenig, M.; Nakatsutsumi, M.; Morace, A.

    2014-11-15

    Transmission crystal spectrometers (TCS) are used on many laser facilities to record hard X-ray spectra. During experiments, signal recorded on imaging plates is often degraded by a background noise. Monte-Carlo simulations made with the code GEANT4 show that this background noise is mainly generated by diffusion of MeV electrons and very hard X-rays. An experiment, carried out at LULI2000, confirmed that the use of magnets in front of the diagnostic, that bent the electron trajectories, reduces significantly this background. The new spectrometer SPECTIX (Spectromčtre PETAL ŕ Cristal en TransmIssion X), built for the LMJ/PETAL facility, will include this optimized shielding.

  18. Transport of Radioactive Material by Alpha Recoil

    SciTech Connect (OSTI)

    Icenhour, A.S.

    2005-05-19

    The movement of high-specific-activity radioactive particles (i.e., alpha recoil) has been observed and studied since the early 1900s. These studies have been motivated by concerns about containment of radioactivity and the protection of human health. Additionally, studies have investigated the potential advantage of alpha recoil to effect separations of various isotopes. This report provides a review of the observations and results of a number of the studies.

  19. Alpha particles in effective field theory

    SciTech Connect (OSTI)

    Caniu, C.

    2014-11-11

    Using an effective field theory for alpha (?) particles at non-relativistic energies, we calculate the strong scattering amplitude modified by Coulomb corrections for a system of two ?s. For the strong interaction, we consider a momentum-dependent interaction which, in contrast to an energy dependent interaction alone [1], could be more useful in extending the theory to systems with more than two ? particles. We will present preliminary results of our EFT calculations for systems with two alpha particles.

  20. Calibrations of alpha Cen A & B

    E-Print Network [OSTI]

    P. Morel; J. Provost; Y. Lebreton; F. Thevenin; G. Berthomieu

    2000-10-10

    Detailed evolutionary models of the visual binary alpha Centauri, including pre main-sequence evolution, have been performed using the masses recently determined by Pourbaix et al. (1999). Models have been constructed using the CEFF equation of state, OPAL opacities, NACRE thermonuclear reaction rates and microscopic diffusion. A chi^2-minimization is performed to derive the most reliable set of modeling parameters wp={t_alpha Cen, Yi, [Fe/H]i, alpha A, alpha B}, where t alpha Cen is the age of the system, Yi the initial helium content, [Fe/H]i the initial metallicity and, alpha A and alpha B the convection parameters of the two components. Using the basic Bohm-Vitense (1958) mixing-length theory of convection, we derive wp BV={2710 Myr, 0.284,0.257, 1.53, 1.57}. We obtain a noticeably smaller age than estimated previously, in agreement with Pourbaix et al. (1999), mainly because of the larger masses. If convective core overshoot is considered we get wp ov={3530 Myr, 0.279,0.264,1.64,1.66}. The use of Canuto & Mazitelli (1991, 1992) convection theory leads to the set wp CM={4086 Myr, 0.271, 0.264, 0.964, 0.986}. Using the observational constraints adopted by Guenther & Demarque (2000), and the basic mixing-length theory, we obtain wp GD={5640 Myr, 0.300, 0.296, 1.86, 1.97} and surface lithium depletions close to their observed values. A seismological analysis of our calibrated models has been performed. The determination of large and small spacings between the frequencies of acoustic oscillations from seismic observations would help to discriminate between the models of alpha Cen computed with different masses and to confirm or rules out the new determination of masses.

  1. Preparation and properties of (R)-(-)-1-azabicyclo(2. 2. 2)oct-3-yl- (R)-(+)-alpha-hydroxy-alpha-(4-( sup 125 I)iodophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2. 2. 2)oct-3-yl-(S)-(-)-alpha-hydroxy-alpha- (4-( sup 125 I)iodophenyl)-alpha-phenyl acetate as potential radiopharmaceuticals

    SciTech Connect (OSTI)

    Cohen, V.I.; Rzeszotarski, W.J.; Gibson, R.E.; Fan, L.H.; Reba, R.C. )

    1989-10-01

    rac-4-Nitrobenzilic acid was synthesized and resolved with quinidine and quinine to give the corresponding (R)- and (S)-salts. The resolved diastereomeric salts were converted to (R)- and (S)-4-nitrobenzilic acids and subsequent esterification gave their corresponding ethyl esters. Transesterification with (R)-(-)-3-quinuclidinol afforded (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)-alpha-hydroxy-alpha- (4-nitrophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy- alpha-(4-nitrophenyl)-alpha-phenyl acetate. After hydrogenation, the (R,R)- and (R,S)-amines were converted to the respective triazene derivatives. The triazene derivatives reacted with sodium ({sup 125}I)iodide to give (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)- alpha-hydroxy-alpha-(4-({sup 125}I)iodophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy- alpha-(4-(125I)iodophenyl)-alpha-phenyl acetate. The evaluation of their affinities to muscarinic acetylcholine receptors (MAcChR) shows that (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy-alpha-(4- ({sup 125}I)iodophenyl)-alpha-phenyl acetate exhibits an affinity for the MAcChR from corpus striatum that is approximately threefold lower than that of (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)-alpha-hydroxy-alpha-(4- ({sup 125}I)iodophenyl)-alpha-phenyl acetate.

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

    DOE Patents [OSTI]

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

    2002-07-30

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

  3. Alpha-beta radiation detector

    DOE Patents [OSTI]

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

    1998-01-01

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

  4. Periodic magnetic fieldas a polarized and focusing thermal neutron spectrometer and monochromator

    E-Print Network [OSTI]

    2010-01-01

    Carlile, Experimental Neutron Scattering ?Oxford Universitysmall angle neutron scattering, and neutron absorptionbirefringent to neutrons, and uses scattering length b F in

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

    E-Print Network [OSTI]

    Green, Michael A

    2011-01-01

    free convection and radiation heat transfer. The resistors2 . If the heat transfer is by radiation only, the resistorThe worst-case heat transfer will be by radiation only. The

  6. Synthesis of 3-amino-4-hydroxylaminothiazolidine-2-thiones and 2,3-dimethyl-4. cap alpha. ,5-dihydro-7-thioxothiazolo(3,4-b)-1,2,4-triazines

    SciTech Connect (OSTI)

    Epshtein, S.P.; Orlova, T.I.; Rukasov, A.F.; Tashchi, V.P.; Putsykin, Yu. G.

    1987-10-01

    The reaction of dimeric nitroso chlorides of olefins with potassium dithiocarbazate was used to synthesize 3-amino-4-hydroxylaminothiazolidine-2-thiones, which undergo rearrangement to 2-mercapto-1,3,4-thiadiazines on heating and react with butane-2,3-dione to give 2,3-dimethyl-4..cap alpha..,5-dihydro-7-thioxothiazolo(3,4-b)-1,2,4-triazine 4-oxides. The latter are reduced by sodium borohydride to the corresponding 3,4,4..cap alpha..,5-tetrahydro-7-thioxo derivatives. The IR spectra of KBr pellets of the compounds were recorded with a Perkin-Elmer spectrometer. The UV spectra of solutions in ethanol were obtained with a Specord UV spectrophotometer. The PMR spectra of solutions of the compounds in d/sub 6/-DMSO were obtained with a Varian FT-80A spectrometer with tetramethylsilane (TMS) as the internal standard.

  7. Positron lifetime spectrometer using a DC positron beam

    DOE Patents [OSTI]

    Xu, Jun; Moxom, Jeremy

    2003-10-21

    An entrance grid is positioned in the incident beam path of a DC beam positron lifetime spectrometer. The electrical potential difference between the sample and the entrance grid provides simultaneous acceleration of both the primary positrons and the secondary electrons. The result is a reduction in the time spread induced by the energy distribution of the secondary electrons. In addition, the sample, sample holder, entrance grid, and entrance face of the multichannel plate electron detector assembly are made parallel to each other, and are arranged at a tilt angle to the axis of the positron beam to effectively separate the path of the secondary electrons from the path of the incident positrons.

  8. A 100-kc modulation system for an EPR microwave spectrometer 

    E-Print Network [OSTI]

    Stewart, Frank Edwin

    1964-01-01

    (1); how- ever, g will differ from the "spin-only" value given by Equation (3) ~ The deviation oi' g from that value is a measure of the degree to which the orbital angular momentum is effective in generating the paramagnetism associated... spectrometers require unpaired spin concentrations 10 greater than 10 for detection. The collective effects of a large number of electron paramagnets, called spina, will now be investigated. Let N be the total number of spins per unit volume in the 0 sample...

  9. Miniature quadrupole mass spectrometer having a cold cathode ionization source

    DOE Patents [OSTI]

    Felter, Thomas E. (Livermore, CA)

    2002-01-01

    An improved quadrupole mass spectrometer is described. The improvement lies in the substitution of the conventional hot filament electron source with a cold cathode field emitter array which in turn allows operating a small QMS at much high internal pressures then are currently achievable. By eliminating of the hot filament such problems as thermally "cracking" delicate analyte molecules, outgassing a "hot" filament, high power requirements, filament contamination by outgas species, and spurious em fields are avoid all together. In addition, the ability of produce FEAs using well-known and well developed photolithographic techniques, permits building a QMS having multiple redundancies of the ionization source at very low additional cost.

  10. Cryostat for Ultra-low-energy Threshold Germanium Spectrometers

    SciTech Connect (OSTI)

    Aalseth, Craig E.; Bonicalzi, Ricco; Fast, James E.; Hossbach, Todd W.; Orrell, John L.; Overman, Cory T.; VanDevender, Brent A.

    2013-04-01

    Abstract: This paper presents progress on the development of a cryostat intended to improve upon the low-energy threshold (below 0.5 keV) of p-type point contact germanium gamma-ray spectrometers. Ultra-low energy thresholds are important in the detection of low-energy nuclear recoils, an event class relevant to both dark matter direct detection and measurement of coherent neutrino-nucleus scattering. The cryostat design, including a thermal and electrical-field model, is presented. A prototype cryostat has been assembled and data acquired to evaluate its vacuum and thermal performance.

  11. Cryostat for Ultra-low-energy Threshold Germanium Spectrometers

    E-Print Network [OSTI]

    Craig E. Aalseth; Ricco M. Bonicalzi; James E. Fast; Todd W. Hossbach; John L. Orrell; Cory T. Overman; Brent A. Vandevender

    2012-10-08

    This paper presents progress on the development of a cryostat intended to improve upon the low-energy threshold (below 0.5 keV) of p-type point contact germanium gamma-ray spectrometers. Ultra-low energy thresholds are important in the detection of low-energy nuclear recoils, an event class relevant to both dark matter direct detection and measurement of coherent neutrino-nucleus scattering. The cryostat design, including a thermal and electrical-field model, is given. A prototype cryostat has been assembled and data acquired to evaluate its vacuum and thermal performance.

  12. Two RICH detectors as velocity spectrometers in the CKM experiment

    SciTech Connect (OSTI)

    Jurgen Engelfried et al.

    2002-09-04

    We present the design of two velocity spectrometers, to be used in the recently approved CKM experiment. CKM's main goal is the measurement of the branching ratio of K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} with a precision of 10%, via decays in flight of the K{sup +}. The design of both RICH detectors is based on the SELEX Phototube RICH. We will discuss the design and the expected performance, based on studies with SELEX data and Monte Carlo Simulations.

  13. Design and evaluation of a miniaturized Particle Desorption Mass Spectrometer 

    E-Print Network [OSTI]

    Davis, Kelly Vaughn

    1987-01-01

    Detail of mass spectrometer showing primary fission fragments, desorbed ions, and start and stop curcuits. 15 Biasing network for the microchannel plate detectors 16 5 Schematic of flight tube showing EPG 18 Schematic of stainless steel sample... convenient source of these high-energy heavy ions is the radionuclide Californium-252. This element undergoes spontaneous fission as 3'/o of its total decay scheme (6). The fission fragments range in energy from 80 to 100 MeV and in mass from 100 to 140...

  14. Linear electric field time-of-flight ion mass spectrometer

    DOE Patents [OSTI]

    Funsten, Herbert O. (Los Alamos, NM); Feldman, William C. (Los Alamos, NM)

    2008-06-10

    A linear electric field ion mass spectrometer having an evacuated enclosure with means for generating a linear electric field located in the evacuated enclosure and means for injecting a sample material into the linear electric field. A source of pulsed ionizing radiation injects ionizing radiation into the linear electric field to ionize atoms or molecules of the sample material, and timing means determine the time elapsed between ionization of atoms or molecules and arrival of an ion out of the ionized atoms or molecules at a predetermined position.

  15. Experiments with the High Resolution Kaon Spectrometer at Jlab Hall C and the New Spectroscopy of ^12_Lambda B Hypernuclei

    SciTech Connect (OSTI)

    Tang, Liguang; Chen, Chunhua; Gogami, Toshiyuki; Kawama, Daisuke; Han, Yuncheng; Yuan, Lulin; Matsumura, Akihiko; Okayasu, Yuichi; Seva, Tomislav; Rodriguez, Victor; Baturin, Pavlo; Acha Quimper, Armando; Achenbach, Carsten; Ahmidouch, Abdellah; Albayrak, Ibrahim; Androic, Darko; Asaturyan, Arshak; Asaturyan, Razmik; Ates, Ozgur; Badui, Rafael; Baker, Oliver; Benmokhtar, Fatiha; Boeglin, Werner; Bono, Jason; Bosted, Peter; Brash, Edward; Carter, Philip; Carlini, Roger; Chiba, Atsushi; Christy, Michael; Cole, Leon; Dalton, Mark; Danagoulian, Samuel; Daniel, Aji; De Leo, Raffaele; Dharmawardane, Kahanawita; Doi, Daisuke; Egiyan, Kim; Elaasar, Mostafa; Ent, Rolf; Fenker, Howard; Fujii, Yu; Furic, Miroslav; Gabrielyan, Marianna; Gan, Liping; Garibaldi, Franco; Gaskell, David; Gasparian, Ashot; Gibson, Edward; Gueye, Paul; Hashimoto, Osamu; Honda, D.; Horn, Tanja; Hu, Bitao; Hungerford, Ed; Jayalath, Chandana; Jones, Mark; Johnston, Kathleen; Kalantarians, Narbe; Kanda, Hiroki; Kaneta, M.; Kato, F.; Kato, Seigo; Kawai, Masaharu; Keppel, Cynthia; Khanal, Hari; Kohl, M.; Kramer, Laird; Lan, Kejian; Li, Ya; Habarakada Liyanage, Anusha; Luo, Wei; Mack, David; Maeda, Kazushige; Malace, Simona; Margaryan, Amur; Marikyan, Gagik; Markowitz, Pete; Maruta, Tomofumi; Maruyama, Nayuta; Maxwell, Victor; Millener, David; Miyoshi, Toshinobu; Mkrtchyan, Arthur; Mkrtchyan, Hamlet; Motoba, Toshio; Nagao, Sho; Nakamura, Satoshi; Narayan, Amrendra; Neville, Casey; Niculescu, Gabriel; Niculescu, Maria; Nunez, Angel; Nuruzzaman, nfn; Nomura, Hiroshi; Nonaka, Kenichi; Ohtani, Atsushi; Oyamada, Masamichi; Perez, Naipy; Petkovic, Tomislav; Pochodzalla, J.; Qiu, Xiyu; Randeniya, Kapugodage; Raue, Brian; Reinhold, Joerg; Rivera, R.; Roche, Julie; Samanta, Chhanda; Sato, Yoshinori; Sawatzky, Bradley; Segbefia, Edwin; Schott, Diane; Shichijo, Ayako; Simicevic, Neven; Smith, Gregory; Song, Yushou; Sumihama, Mizuki; Tadevosyan, Vardan; Takahashi, Toshiyuki; Taniya, Naotaka; Tsukada, Kyo; Tvaskis, Vladas; Veilleux, Micah; Vulcan, William; Wells, Steven; Wesselmann, Frank; Wood, Stephen; Yamamoto, Taku; Yan, Chen; Ye, Z.; Yokota, Kosuke; Zhamkochyan, Simon; Zhu, Lingyan

    2014-09-01

    Since the pioneering experiment, E89-009 studying hypernuclear spectroscopy using the $(e,e^{\\prime}K^+)$ reaction was completed, two additional experiments, E01-011 and E05-115, were performed at Jefferson Lab. These later experiments used a modified experimental design, the "Tilt Method", to dramatically suppress the large electromagnetic background, and allowed for a substantial increase in luminosity. Additionally, a new kaon spectrometer, HKS (E01-011), a new electron spectrometer, HES, and a new splitting magnet were added to produce precision, high-resolution hypernuclear spectroscopy. These two experiments, E01-011 and E05-115, resulted in two new data sets, producing sub-MeV energy resolution in the spectra of ${}^{7}_{\\Lambda}\\text{He}$, ${}^{12}_{\\Lambda}\\text{B}$ and ${}^{28}_{\\Lambda} \\text{Al}$ and ${}^{7}_{\\Lambda}\\text{He}$, ${}^{10}_{\\Lambda}\\text{Be}$, ${}^{12}_{\\Lambda}\\text{B}$ and ${}^{52}_{\\Lambda}\\text{V}$. All three experiments obtained a ${}^{12}_{\\Lambda}\\text{B}$, spectrum, which is the most characteristic $p$-shell hypernucleus and is commonly used for calibration. Independent analyses of these different experiments demonstrate excellent consistency and provide the clearest level structure to date of this hypernucleus as produced by the $(e,e^{\\prime}K^+)$ reaction. This paper presents details of these experiments, and the extraction and analysis of the observed ${}^{12}_{\\Lambda}\\text{B}$ spectrum.

  16. Piper Alpha and Independence Marion King Hubbert (1903 1989) Piper Alpha (6 July 1988)

    E-Print Network [OSTI]

    be a second Piper Alpha tragedy for Scotland if its historical effect on oil production has not been by the Yes campaign. Following Piper Alpha, oil production was deliberately cut back in order to allow assessment of Scotland's likely remaining oil wealth (including new finds). The Hubbert production forecast

  17. R(s) and hadronic tau-Decays in Order alpha_s^4: technical aspects

    E-Print Network [OSTI]

    P. A. Baikov; K. G. Chetyrkin; J. H. Kühn

    2009-06-16

    We report on some technical aspects of our calculation of alpha_s^4 corrections to R(s) and the semi-leptonic tau decay width [1-3]. We discuss the inner structure of the result as well as the issue of its correctness. We demonstrate recently appeared independent evidence positively testing one of two components of the full result.

  18. Front. Phys., 2013, 8(6): 605608 DOI 10.1007/s11467-013-0351-7

    E-Print Network [OSTI]

    Zhang, Bing

    ) in the hard - ray band; as well as Cosmic Ray Energetics and Mass (CREAM) and Alpha Magnetic Spectrometer-thermal electro- magnetic radiation, are also believed to be emitters of other signals outside the electromagnetic

  19. A solenoidal electron spectrometer for a precision measurement of the neutron $?$-asymmetry with ultracold neutrons

    E-Print Network [OSTI]

    B. Plaster; R. Carr; B. W. Filippone; D. Harrison; J. Hsiao; T. M. Ito; J. Liu; J. W. Martin; B. Tipton; J. Yuan

    2008-06-12

    We describe an electron spectrometer designed for a precision measurement of the neutron $\\beta$-asymmetry with spin-polarized ultracold neutrons. The spectrometer consists of a 1.0-Tesla solenoidal field with two identical multiwire proportional chamber and plastic scintillator electron detector packages situated within 0.6-Tesla field-expansion regions. Select results from performance studies of the spectrometer with calibration sources are reported.

  20. Optical apparatus for forming correlation spectrometers and optical processors

    DOE Patents [OSTI]

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

    1999-05-18

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

  1. ATLAS Muon Spectrometer Upgrades for the High Luminosity LHC

    E-Print Network [OSTI]

    Valderanis, Chrysostomos; The ATLAS collaboration

    2015-01-01

    ATLAS Muon Spectrometer Upgrades for the High Luminosity LHC The luminosity of the LHC will increase up to 2x10^34 cm-2s-1 after the long shutdown in 2019 (phase-1 upgrade) and up to 7x10^34 cm-2s-1 after the long shutdown in 2025 (phase-2 upgrade). In order to cope with the increased particle fluxes, upgrades are envisioned for the ATLAS muon spectrometer. At phase-1, the current innermost stations of the ATLAS muon endcap tracking system (the Small Wheels) will be upgraded with 2x4-layer modules of Micromega detectors, sandwiched by two 4 layer modules of small strip Thin Gap Chambers on either side. Each 4-layer module of the so-called New Small Wheels covers a surface area of approximately 2 to 3 m2 for a total active area of 1200 m2 each for the two technologies. On such large area detectors, the mechanical precision (30 \\mu m along the precision coordinate and 80 \\mu m along the beam) is a key point and must be controlled and monitored along the process of construction and integration. The design and re...

  2. The response of a Bonner Sphere spectrometer to charged hadrons

    E-Print Network [OSTI]

    Agosteo, S; Fassň, A; Silari, M; 10.1093/rpd/nch187

    2004-01-01

    Bonner sphere spectrometers (BSSs) are employed in neutron spectrometry and dosimetry since many years. Recent developments have seen the addition to a conventional BSS of one or more detectors (moderator plus thermal neutron counter) specifically designed to improve the overall response of the spectrometer to neutrons above 10 MeV. These additional detectors employ a shell of material with a high mass number (such as lead) within the polyethylene moderator, in order to slow down high-energy neutrons via (n, xn) reactions. A BSS can be used to measure neutron spectra both outside accelerator shielding and from an unshielded target. Measurements were recently performed at CERN of the neutron yield and spectral fluence at various angles from unshielded, semithick copper, silver and lead targets, bombarded by a mixed proton/pion beam with 40 GeV per c momentum. These experiments have provided evidence that under certain circumstances, the use of lead-enriched moderators may present a problem: these detectors wer...

  3. Light ion transfer reactions with the HELIOS spectrometer

    SciTech Connect (OSTI)

    Back, B. B.; Collaboration: HELIOS Collaboration

    2012-10-20

    Light-ion induced transfer and inelastic scattering reactions on stable or long-lived targets have been used extensively to study the structure of nuclei near the line of {beta}-stability, and much of the detailed information on the single-particle structure of nuclei has been derived from such studies. Recently, however, a substantial expansion of the range of isotopes, for which this nuclear structure information can be obtained, has presented itself by using radioactive beams in inverse kinematics reactions. Such beams are now available at a number of facilities around the world, including the in-flight production method and CARIBU facility at ATLAS. The HELIOS spectrometer, which has been used since August 2008 at ATLAS, circumvents many of the problems associated with inverse kinematics. In this talk I will discuss the principle of the spectrometer as well as some of main physics results that have been obtained to date in nuclei ranging from {sup 13}B to {sup 137}Xe using both stable and radioactive beams.

  4. Progress on the Modeling and Modification of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2013-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.E E Transactions on Applied Superconductivity 15, No. 2, p.and Modeling of the MICE Superconducting Spectrometer

  5. Update on the Modification and Testing of the MICE Superconducting Spectrometer Solenoids

    E-Print Network [OSTI]

    Virostek, S.P.

    2013-01-01

    IEEE Transactions on Applied Superconductivity 15, No. 2, p.IEEE Transactions on Applied Superconductivity 15, No. 2, p.TESTING OF THE MICE SUPERCONDUCTING SPECTROMETER SOLENOIDS*

  6. A NOVEL X-RAY IMAGING CRYSTAL SPECTROMETER FOR DOPPLER MEASUREMENTS...

    Office of Scientific and Technical Information (OSTI)

    new spectrometer concept is also of interest for the diagnosis of burning plasmas on future machines. This paper presents recent experimental results from Aclator C-Mod and...

  7. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1987-10-06

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines. 3 figs.

  8. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, John A. (Livermore, CA); Stone, Roger R. (Walnut Creek, CA); Fabyan, Joseph (Livermore, CA)

    1987-01-01

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  9. Gauss-Bonnet holographic superconductors with magnetic field

    E-Print Network [OSTI]

    M. R. Setare; D. Momeni

    2011-10-28

    We study the Gauss-Bonnet (GB) holographic superconductors in the presence of an external magnetic field. We describe the phenomena away from the probe limit. We derive the critical magnetic field of the GB holographic superconductors with backreaction. Our analytical approach matches the numerical calculations. We calculate the backreaction corrections up to first order of $O(\\kappa^2=8\\pi G)$ to the critical temperature $T_C$ and the critical magnetic field $B_C$ for a GB superconductor. We show that the GB coupling $\\alpha$ makes the condensation weaker but the backreaction corrections $O(\\kappa^2)$ make the critical magnetic field stronger.

  10. Alternating current long range alpha particle detector

    DOE Patents [OSTI]

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

    1993-02-16

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

  11. Synthesis of peptide .alpha.-thioesters

    DOE Patents [OSTI]

    Camarero, Julio A. (Livermore, CA); Mitchell, Alexander R. (Livermore, CA); De Yoreo, James J. (Clayton, CA)

    2008-08-19

    Disclosed herein is a new method for the solid phase peptide synthesis (SPPS) of C-terminal peptide .alpha. thioesters using Fmoc/t-Bu chemistry. This method is based on the use of an aryl hydrazine linker, which is totally stable to conditions required for Fmoc-SPPS. When the peptide synthesis has been completed, activation of the linker is achieved by mild oxidation. The oxidation step converts the acyl-hydrazine group into a highly reactive acyl-diazene intermediate which reacts with an .alpha.-amino acid alkylthioester (H-AA-SR) to yield the corresponding peptide .alpha.-thioester in good yield. A variety of peptide thioesters, cyclic peptides and a fully functional Src homology 3 (SH3) protein domain have been successfully prepared.

  12. Workshop on Precision Measurements of alphas

    E-Print Network [OSTI]

    S. Bethke; A. H. Hoang; S. Kluth; J. Schieck; I. W. Stewart; S. Aoki; M. Beneke; J. Blumlein; N. Brambilla; S. Brodsky; S. Descotes-Genon; J. Erler; S. Forte; T. Gehrmann; C. Glasman; M. Golterman; S. Hashimoto; A. Kronfeld; J. Kuhn; P. Lepage; A. Martin; V. Mateu; S. Menke; Y. Nomura; C. Pahl; F. Petriello; A. Pich; K. Rabbertz; G. Salam; H. Schulz; R. Sommer; M. Steinhauser; B. Webber; CP. Yuan; G. Zanderighi

    2011-10-22

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

  13. Fan-less long range alpha detector

    DOE Patents [OSTI]

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

    1994-05-10

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

  14. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1985-02-12

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  15. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode

    SciTech Connect (OSTI)

    Rieker, G. B.; Poehlmann, F. R.; Cappelli, M. A.

    2013-07-15

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions.

  16. Magnetic nanotubes

    DOE Patents [OSTI]

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

    2010-11-16

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

  17. The 28th International Cosmic Ray Conference 1 The AMS-02 TRD for the International Space Station

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    , Italy Abstract The Alpha Magnetic Spectrometer (AMS-02) is an experiment which will be mounted Magnetic Spectrometer is an experiment which will be mounted on the International Space Station (ISS, to provide tracking in the bending and non-bending directions of the 0.8 T superconducting magnet as well

  18. A spatially resolving x-ray crystal spectrometer for measurement of ion-temperature and rotation-velocity profiles on the Alcator C-Mod tokamak

    SciTech Connect (OSTI)

    Hill, K. W.; Bitter, M. L.; Scott, S. D.; Ince-Cushman, A.; Reinke, M.; Rice, J. E.; Beiersdorfer, P.; Gu, M.-F.; Lee, S. G.; Broennimann, Ch.; Eikenberry, E. F.

    2008-10-15

    A new spatially resolving x-ray crystal spectrometer capable of measuring continuous spatial profiles of high resolution spectra ({lambda}/d{lambda}>6000) of He-like and H-like Ar K{alpha} lines with good spatial ({approx}1 cm) and temporal ({approx}10 ms) resolutions has been installed on the Alcator C-Mod tokamak. Two spherically bent crystals image the spectra onto four two-dimensional Pilatus II pixel detectors. Tomographic inversion enables inference of local line emissivity, ion temperature (T{sub i}), and toroidal plasma rotation velocity (v{sub {phi}}) from the line Doppler widths and shifts. The data analysis techniques, T{sub i} and v{sub {phi}} profiles, analysis of fusion-neutron background, and predictions of performance on other tokamaks, including ITER, will be presented.

  19. Linear electronic field time-of-flight ion mass spectrometers

    DOE Patents [OSTI]

    Funsten, Herbert O. (Los Alamos, NM)

    2010-08-24

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

  20. Ion mobility spectrometer using frequency-domain separation

    DOE Patents [OSTI]

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

    1998-08-04

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

  1. Ion mobility spectrometer using frequency-domain separation

    DOE Patents [OSTI]

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

    1998-01-01

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

  2. Imaging X-ray Thomson Scattering Spectrometer Design and Demonstration

    SciTech Connect (OSTI)

    Gamboa, E.J.; Huntington, C.M.; Trantham, M.R.; Keiter, P.A; Drake, R.P.; Montgomery, David; Benage, John F.; Letzring, Samuel A.

    2012-05-04

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

  3. THE ABSOLUTE CALIBRATION OF THE EUV IMAGING SPECTROMETER ON HINODE

    SciTech Connect (OSTI)

    Warren, Harry P.; Ugarte-Urra, Ignacio; Landi, Enrico

    2014-07-01

    We investigate the absolute calibration of the EUV Imaging Spectrometer (EIS) on Hinode by comparing EIS full-disk mosaics with irradiance observations from the EUV Variability Experiment on the Solar Dynamics Observatory. We also use extended observations of the quiet corona above the limb combined with a simple differential emission measure model to establish new effective area curves that incorporate information from the most recent atomic physics calculations. We find that changes to the EIS instrument sensitivity are a complex function of both time and wavelength. We find that the sensitivity is decaying exponentially with time and that the decay constants vary with wavelength. The EIS short wavelength channel shows significantly longer decay times than the long wavelength channel.

  4. Isotopic response with small scintillator based gamma-ray spectrometers

    DOE Patents [OSTI]

    Madden, Norman W. (Sparks, NV); Goulding, Frederick S. (Lafayette, CA); Asztalos, Stephen J. (Oakland, CA)

    2012-01-24

    The intrinsic background of a gamma ray spectrometer is significantly reduced by surrounding the scintillator with a second scintillator. This second (external) scintillator surrounds the first scintillator and has an opening of approximately the same diameter as the smaller central scintillator in the forward direction. The second scintillator is selected to have a higher atomic number, and thus has a larger probability for a Compton scattering interaction than within the inner region. Scattering events that are essentially simultaneous in coincidence to the first and second scintillators, from an electronics perspective, are precluded electronically from the data stream. Thus, only gamma-rays that are wholly contained in the smaller central scintillator are used for analytic purposes.

  5. Dynamic multiplexed analysis method using ion mobility spectrometer

    DOE Patents [OSTI]

    Belov, Mikhail E [Richland, WA

    2010-05-18

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

  6. Transformer Recharging with Alpha Channeling in Tokamaks

    SciTech Connect (OSTI)

    N.J. Fisch

    2009-12-21

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

  7. A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA and the NIF

    E-Print Network [OSTI]

    A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA, 063502 (2014) A compact neutron spectrometer for characterizing inertial confinement fusion implosions-resolution spectroscopy used to measure inertial confinement fusion neutron spectra on Omega (invited)a) Rev. Sci. Instrum

  8. Passive Spectroscopy Bolometers, Grating- And X-Ray Imaging Crystal Spectrometers

    SciTech Connect (OSTI)

    Bitter, M; Hill, K W; Scott, S; Paul, S; Ince-Cushmann, A; Reinke, M; Rice, J; Beiersdorfer, P; Gu, M F; Lee, S G; Broennimann, C; Eikenberry, E F

    2007-11-07

    This tutorial gives a brief introduction into passive spectroscopy and describes the working principles of bolometers, a high-resolution grating spectrometer, and a novel X-ray imaging crystal spectrometer, which is of particular interest for profile measurements of the ion temperature and plasma rotation velocity on ITER and future burning plasma experiments.

  9. Simulation-guided optimization of small-angle analyzer geometry in the neutron backscattering spectrometer SPHERES

    SciTech Connect (OSTI)

    Wuttke, Joachim; Zamponi, Michaela [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at MLZ, Lichtenbergstraße 1, 85747 Garching (Germany)] [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at MLZ, Lichtenbergstraße 1, 85747 Garching (Germany)

    2013-11-15

    The resolution of neutron backscattering spectrometers deteriorates at small scattering angles where analyzers deviate from exact backscattering. By reducing the azimuth angle range of the analyzers, the resolution can be improved with little loss of peak intensity. Measurements at the spectrometer SPHERES are in excellent agreement with simulations, which proves the dominance of geometric effects.

  10. Integrated standing-wave transform spectrometer for near infrared optical analysis

    E-Print Network [OSTI]

    Miller, David A. B.

    Integrated standing-wave transform spectrometer for near infrared optical analysis S. R. Bhalotra standing-wave Fourier-transform spectrometer design has been developed for applica- tions in the near IR. Whereas recent development of the standing-wave architecture has been focused on interferometric sensing

  11. Echelle grating multi-order imaging spectrometer utilizing a catadioptric lens

    DOE Patents [OSTI]

    Chrisp, Michael P; Bowers, Joel M

    2014-05-27

    A cryogenically cooled imaging spectrometer that includes a spectrometer housing having a first side and a second side opposite the first side. An entrance slit is on the first side of the spectrometer housing and directs light to a cross-disperser grating. An echelle immersions grating and a catadioptric lens are positioned in the housing to receive the light. A cryogenically cooled detector is located in the housing on the second side of the spectrometer housing. Light from the entrance slit is directed to the cross-disperser grating. The light is directed from the cross-disperser grating to the echelle immersions grating. The light is directed from the echelle immersions grating to the cryogenically cooled detector on the second side of the spectrometer housing.

  12. Gravitational resonance spectroscopy with an oscillating magnetic field gradient in the GRANIT flow through arrangement

    E-Print Network [OSTI]

    G. Pignol; S. Baessler; V. V. Nesvizhevsky; K. Protasov; D. Rebreyend; A. Yu. Voronin

    2014-08-05

    Gravitational resonance spectroscopy consists in measuring the energy spectrum of bouncing ultracold neutrons above a mirror by inducing resonant transitions between different discrete quantum levels. We discuss how to induce the resonances with a flow through arrangement in the GRANIT spectrometer, excited by an oscillating magnetic field gradient. The spectroscopy could be realized in two distinct modes (so called DC and AC) using the same device to produce the magnetic excitation. We present calculations demonstrating the feasibility of the newly proposed AC mode.

  13. Study of alpha background in a dark matter detector

    E-Print Network [OSTI]

    Yegoryan, Hayk

    2010-01-01

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

  14. Nuclear isospin asymmetry in $\\alpha$ decays of heavy nuclei

    E-Print Network [OSTI]

    Shin, Eunkyoung; Hyun, Chang Ho; Oh, Yongseok

    2015-01-01

    The effects of nuclear isospin asymmetry on $\\alpha$ decay lifetimes of heavy nuclei are investigated within various phenomenological models of nuclear potential for the $\\alpha$ particle. We consider the widely used simple square well potential and Woods-Saxon potential, and modify them by including an isospin asymmetry term. We then suggest a model for the potential of the $\\alpha$ particle motivated by a microscopic phenomenological approach of the Skyrme force model, which naturally introduce the isospin dependent form of the nuclear potential for the $\\alpha$ particle. The empirical $\\alpha$ decay lifetime formula of Viola and Seaborg is also modified to include isospin asymmetry effects. The obtained $\\alpha$ decay half-lives are in good agreement with the experimental data and we find that including the nuclear isospin effects somehow improves the theoretical results for $\\alpha$ decay half-lives. The implications of these results are discussed and the predictions on the $\\alpha$ decay lifetimes of sup...

  15. Antibody-mediated reduction of {alpha}-ketoamides

    DOE Patents [OSTI]

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

    1998-06-09

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

  16. The effects of alpha particle irradiation on stainless steel 

    E-Print Network [OSTI]

    Shipp, John Douglas

    1999-01-01

    A Monte Carlo code was developed to calculate the alpha particle emission rate from WGPu. It yielded information pertaining to the alpha particle source strength at the WGPU and stainless steel interface as well as the damage production and He...

  17. Magnetic monopoles

    SciTech Connect (OSTI)

    Fryberger, D.

    1984-12-01

    In this talk on magnetic monopoles, first the author briefly reviews some historical background; then, the author describes what several different types of monopoles might look like; and finally the author discusses the experimental situation. 81 references.

  18. A velocity map imaging spectrometer for electron?ion and ion?ion coincidence experiments with synchrotron radiation

    E-Print Network [OSTI]

    Rolles, D.; Advanced Light Source

    2008-01-01

    map imaging (VMI) spectrometer optimized for angle-resolved photoionization experiments with synchrotron radiation (map imaging spectrometer for electron-ion and ion-ion coincidence experiments with synchrotron radiation

  19. Neutron Spectrometry for D­T Plasmas in JET, using a Tandem Annular-radiator Proton-recoil Spectrometer

    E-Print Network [OSTI]

    Neutron Spectrometry for D­T Plasmas in JET, using a Tandem Annular-radiator Proton-recoil Spectrometer

  20. Fast-ion-beam photoelectron spectrometer K. A. Hanold, C. R. Sherwood, M. C. Garner, and R. E. Continetti

    E-Print Network [OSTI]

    Continetti, Robert E.

    Fast-ion-beam photoelectron spectrometer K. A. Hanold, C. R. Sherwood, M. C. Garner, and R. E) A high-collection-efficiency fast-ion-beam photoelectron spectrometer is described. In a straight time of the photoelectron laboratory energy to center-of-mass energy. The fast-ion-beam photoelectron spectrometer is used

  1. Alpha Cluster Model of Atomic Nuclei

    E-Print Network [OSTI]

    Sosin, Zbigniew; Kallunkathariyil, Jinesh; ?ukasik, Jerzy; Paw?owski, Piotr

    2015-01-01

    The description of the nuclear system in its ground state and at low excitations based on the equation of state (EoS) around the saturation density is presented. In the expansion of the EoS around the saturation point additional spin polarization terms are taken into account. In addition for atomic nuclei a correction of the average nucleonic energy for the surface energy is introduced. The ground state configurations for the N=Z even-even nuclei, obtained with the proposed EoS, exhibit a clear cluster structure. At the nuclear surface these clusters can be identified as alpha particles. Taking into account an additional interaction between clusters the binding energy and sizes of the considered nuclei are very accurately described. From properties of the {\\alpha} particle, 3He and t limits of the EoS parameters are established.

  2. Automatically processed alpha-track radon monitor

    DOE Patents [OSTI]

    Langner, G.H. Jr.

    1993-01-12

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

  3. Automatically processed alpha-track radon monitor

    DOE Patents [OSTI]

    Langner, Jr., G. Harold (Mack, CO)

    1993-01-01

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

  4. Magnetic fields, spots and weather in chemically peculiar stars

    E-Print Network [OSTI]

    O. Kochukhov

    2007-11-30

    New observational techniques and sophisticated modelling methods has led to dramatic breakthroughs in our understanding of the interplay between the surface magnetism, atomic diffusion and atmospheric dynamics in chemically peculiar stars. Magnetic Doppler images, constructed using spectropolarimetric observations of Ap stars in all four Stokes parameters, reveal the presence of small-scale field topologies. Abundance Doppler mapping has been perfected to the level where distributions of many different chemical elements can be deduced self-consistently for one star. The inferred chemical spot structures are diverse and do not always trace underlying magnetic field geometry. Moreover, horizontal chemical inhomogeneities are discovered in non-magnetic CP stars and evolving chemical spots are observed for the first time in the bright mercury-manganese star alpha And. These results show that in addition to magnetic fields, another important non-magnetic structure formation mechanism acts in CP stars.

  5. Upgrades of the high resolution imaging x-ray crystal spectrometers on experimental advanced superconducting tokamak

    SciTech Connect (OSTI)

    Lu, B.; Wang, F.; Fu, J.; Li, Y.; Wan, B.; Shi, Y.; Bitter, M.; Hill, K. W.; Lee, S. G.

    2012-10-15

    Two imaging x-ray crystal spectrometers, the so-called 'poloidal' and 'tangential' spectrometers, were recently implemented on experimental advanced superconducting tokamak (EAST) to provide spatially and temporally resolved impurity ion temperature (T{sub i}), electron temperature (T{sub e}) and rotation velocity profiles. They are derived from Doppler width of W line for Ti, the intensity ratio of Li-like satellites to W line for Te, and Doppler shift of W line for rotation. Each spectrometer originally consisted of a spherically curved crystal and a two-dimensional multi-wire proportional counter (MWPC) detector. Both spectrometers have now been upgraded. The layout of the tangential spectrometer was modified, since it had to be moved to a different port, and the spectrometer was equipped with two high count rate Pilatus detectors (Model 100 K) to overcome the count rate limitation of the MWPC and to improve its time resolution. The poloidal spectrometer was equipped with two spherically bent crystals to record the spectra of He-like and H-like argon simultaneously and side by side on the original MWPC. These upgrades are described, and new results from the latest EAST experimental campaign are presented.

  6. Discovery of the $^{151}$Eu $\\alpha$ decay

    E-Print Network [OSTI]

    Casali, N; Orio, F; Pattavina, L; Beeman, J W; Bellini, F; Cardani, L; Dafinei, I; Di Domizio, S; Di Vacri, M L; Gironi, L; Kosmyna, M B; Nazarenko, B P; Nisi, S; Pessina, G; Piperno, G; Pirro, S; Rusconi, C; Shekhovtsov, A N; Tomei, C; Vignati, M

    2013-01-01

    We report on the observation of the $^{151}$Eu $\\alpha$ decay to the ground state of $^{147}$Pm. We measured a half-life of T_{1/2}=(4.62$\\pm$0.95(stat.)$\\pm$0.68(syst.))$\\times 10^{18}$ y and a Q-value of 1948.9$\\pm$6.9 keV, using a 6.15 g Li$_6$Eu(BO$_3$)$_3$ crystal operated as scintillating bolometer.

  7. A new seismic analysis of Alpha Centauri

    E-Print Network [OSTI]

    A. Thoul; R. Scuflaire; A. Noels; B. Vatovez; M. Briquet; M. -A. Dupret; J. Montalban

    2003-03-20

    Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological data obtained by Bouchy and Carrier (2001, 2002) do help improve our knowledge of the evolutionary status of the system. All the constraints are satisfied with a model which gives an age of about 6 Gyr for the binary.

  8. A new seismic analysis of Alpha Centauri

    E-Print Network [OSTI]

    Thoul, A; Noels, A; Vatovez, B; Briquet, M; Dupret, M A; Montalban, J

    2003-01-01

    Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological data obtained by Bouchy and Carrier (2001, 2002) do help improve our knowledge of the evolutionary status of the system. All the constraints are satisfied with a model which gives an age of about 6 Gyr for the binary.

  9. Alpha Particle Physics Experiments in the Tokamak Fusion Test Reactor

    SciTech Connect (OSTI)

    Budny, R.V.; Darrow, D.S.; Medley, S.S.; Nazikian, R.; Zweben, S.J.; et al.

    1998-12-14

    Alpha particle physics experiments were done on the Tokamak Fusion Test Reactor (TFTR) during its deuterium-tritium (DT) run from 1993-1997. These experiments utilized several new alpha particle diagnostics and hundreds of DT discharges to characterize the alpha particle confinement and wave-particle interactions. In general, the results from the alpha particle diagnostics agreed with the classical single-particle confinement model in magnetohydrodynamic (MHD) quiescent discharges. Also, the observed alpha particle interactions with sawteeth, toroidal Alfvén eigenmodes (TAE), and ion cyclotron resonant frequency (ICRF) waves were roughly consistent with theoretical modeling. This paper reviews what was learned and identifies what remains to be understood.

  10. Order from Chaos: (alpha)-Fe(001) Growth on GaAs(001)

    SciTech Connect (OSTI)

    Tobin, J G; Yu, S W; Morton, S A; Waddill, G D; Thompson, J D; Neal, J R; Shen, T H

    2008-02-08

    The growth of Fe upon GaAs(001) has been studied with Spin-Resolved Photoelectron Spectroscopy (SRPES), Photoelectron Spectroscopy (PES) and X-ray Magnetic Linear Dichroism (XMLD) in PES. Despite evidence of atomic level disorder such as intermixing, an over-layer with the spectroscopic signature of {alpha}-Fe(001), with a bcc real space ordering, is obtained. The results will be discussed in light of the possibility of using such films as a spin polarized source in device applications.

  11. In-situ droplet monitoring for self-tuning spectrometers

    DOE Patents [OSTI]

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

    2010-09-28

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

  12. ASIC for SDD-Based X-ray Spectrometers

    SciTech Connect (OSTI)

    De Geronimo, G.; Fried, J.; Rehak, P.; Ackley, K.; Carini, G.; Chen, W.; Keister, J.; Li, S.; Li, Z.; Pinelli, D.A.; Siddons, D.P.; Vernon, E.; Gaskin, J.A.; Ramsey, B.D.; Tyson, T.A.

    2010-06-16

    We present an application-specific integrated circuit (ASIC) for high-resolution x-ray spectrometers (XRS). The ASIC reads out signals from pixelated silicon drift detectors (SDDs). The pixel does not have an integrated field effect transistor (FET); rather, readout is accomplished by wire-bonding the anodes to the inputs of the ASIC. The ASIC dissipates 32 mW, and offers 16 channels of low-noise charge amplification, high-order shaping with baseline stabilization, discrimination, a novel pile-up rejector, and peak detection with an analog memory. The readout is sparse and based on custom low-power tristatable low-voltage differential signaling (LPT-LVDS). A unit of 64 SDD pixels, read out by four ASICs, covers an area of 12.8 cm{sup 2} and dissipates with the sensor biased about 15 mW/cm{sup 2}. As a tile-based system, the 64-pixel units cover a large detection area. Our preliminary measurements at -44 C show a FWHM of 145 eV at the 5.9 keV peak of a {sup 55}Fe source, and less than 80 eV on a test-pulse line at 200 eV.

  13. Rotary turret and reusable specimen holder for mass spectrometer

    DOE Patents [OSTI]

    Banar, Joseph C. (Los Alamos, NM); Perrin, Richard E. (Jemez Springs, NM); Ostrenga, Raymond A. (Los Alamos, NM)

    1988-01-01

    A sample holder for use in a mass spectrometer is provided for heating a sample to discharge ions through an electrostatic field which focuses and accelerates the ions for analysis. Individual specimen holders form a plurality of filaments for heating the sample materials for ion emission. Mounting devices hold the plurality of filaments at regular spaced apart angles in a closed configuration adjacent the electrostatic field elements. A substantially solid ceramic turret is provided with a plurality of electrical contacts which engage the individual holder means for energizing the filaments and forming a corresponding plurality of radially facing, axially extending first conductive surfaces. A substantially solid stationary turret bearing member is mounted about the rotating turret with a plurality of radially biased second electrical conductive surfaces, mounted to electrically contact facing ones of the plurality of radially facing first conductive surfaces. The assembly provides a large thermal mass for thermal stability and large electrical contact areas for repeatable, stable power input for heating the sample materials. An improved sample holder is also provided having a ceramic body portion for removably engaging conductive wires. The conductive wires are compatible with a selected filament element and the sample material to be analyzed.

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

    SciTech Connect (OSTI)

    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.

  15. X-ray crystal spectrometer upgrade for ITER-like wall experiments at JET

    SciTech Connect (OSTI)

    Shumack, A. E.; Rzadkiewicz, J.; Chernyshova, M.; Czarski, T.; Karpinski, L.; Jakubowska, K.; Scholz, M.; Byszuk, A.; Cieszewski, R.; Kasprowicz, G.; Pozniak, K.; Wojenski, A.; Zabolotny, W.; Dominik, W.; Conway, N. J.; Dalley, S.; Tyrrell, S.; Zastrow, K.-D.; Figueiredo, J. [EFDA-CSU, Culham Science Centre, Abingdon OX14 3DB; Associaçăo EURATOM and others

    2014-11-15

    The high resolution X-Ray crystal spectrometer at the JET tokamak has been upgraded with the main goal of measuring the tungsten impurity concentration. This is important for understanding impurity accumulation in the plasma after installation of the JET ITER-like wall (main chamber: Be, divertor: W). This contribution provides details of the upgraded spectrometer with a focus on the aspects important for spectral analysis and plasma parameter calculation. In particular, we describe the determination of the spectrometer sensitivity: important for impurity concentration determination.

  16. Probing surface distribution of $\\alpha$-cluster in $^{20}$Ne via $\\alpha$-transfer reaction

    E-Print Network [OSTI]

    Fukui, Tokuro; Suhara, Tadahiro; Kanada-En'yo, Yoshiko; Ogata, Kazuyuki

    2015-01-01

    Direct evidence of the $\\alpha$-cluster development in bound states has not been obtained yet although a number of experimental studies were carried out to extract the information of the clustering. In particular in conventional analyses of $\\alpha$-transfer reactions, there exist a few significant problems on reaction models, which are insufficient to qualitatively discuss the cluster structure. We aim to verify the development of the $\\alpha$-cluster structure from observables. As the first application, it is argued to extract the spatial information of the cluster structure of the $^{20}$Ne nucleus in its ground state through the cross section of the $\\alpha$-transfer reaction $^{16}$O($^6$Li,~$d$)$^{20}$Ne. For the analysis of the transfer reaction, we work with the coupled-channels Born approximation (CCBA) approach, in which the breakup effect of $^6$Li is explicitly taken into account by means of the continuum-discretized coupled-channels method (CDCC) based on the three-body $\\alpha + d + {}^{16}$O mo...

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

    E-Print Network [OSTI]

    Ivanova, Viara; Hristov, Jordan

    2011-01-01

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

  18. Magnetized Target Fusion (MTF): Principles, Status, and International Collaboration

    SciTech Connect (OSTI)

    Kirkpatrick, R.C.

    1998-11-16

    Magnetized target fusion (MTF) is an approach to thermonuclear fusion that is intermediate between the two extremes of inertial and magnetic confinement. Target plasma preparation is followed by compression to fusion conditions. The use of a magnetic field to reduce electron thermal conduction and potentially enhance DT alpha energy deposition allows the compression rate to be drastically reduced relative to that for inertial confinement fusion. This leads to compact systems with target driver power and intensity requirements that are orders of magnitude lower than for ICF. A liner on plasma experiment has been proposed to provide a firm proof of principle for MTF.

  19. Magnet Cable Manufacturing

    E-Print Network [OSTI]

    Royet, J.M.

    2011-01-01

    J. Royet, "Magnet Cable Manufacturing", oral presentation atDivision Magnet Cable Manufacturing J. Royet October 1990J I Magnet Cable Manufacturing* John Royet Accelerator &

  20. The Acceleration of Ions in Solar Flares During Magnetic Reconnection

    E-Print Network [OSTI]

    Knizhnik, Kalman; Drake, James F

    2011-01-01

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

  1. {alpha} decay and shape coexistence in the {alpha}-rotor model

    SciTech Connect (OSTI)

    Richards, J.D.; Bingham, C.R.; Nazarewicz, W.; Wauters, J.; Berggren, T.; Berggren, T.; Bingham, C.R.; Nazarewicz, W.; Nazarewicz, W.

    1997-09-01

    The particle-plus-rotor model was employed to study the fine structure seen in the {alpha} decay of even-even neutron-deficient nuclei in the Hg-Po region. The configuration mixing resulting from the shape coexistence between well-deformed prolate bands and spherical (or quasirotational oblate) structures in the daughter nuclei was considered. Experimental {alpha}-decay branching ratios are reproduced within one order of magnitude, except for the case of {sup 180}Hg, where the daughter nucleus {sup 176}Pt is expected to be triaxial in its ground state. The effect of configuration mixing on the relative intensities is discussed in detail, together with the sensitivity of results to the choice of the {alpha}-nucleus optical model parameters. {copyright} {ital 1997} {ital The American Physical Society}

  2. The 106Cd(alpha,alpha)106Cd elastic scattering in a wide energy range for gamma-process studies

    E-Print Network [OSTI]

    A. Ornelas; G. G. Kiss; P. Mohr; D. Galaviz; Zs. Fülöp; Gy. Gyürky; Z. Máté; T. Rauscher; E. Somorjai; K. Sonnabend; A. Zilges

    2015-04-29

    Alpha elastic scattering angular distributions of the 106Cd(alpha,alpha)106Cd reaction were measured at three energies around the Coulomb barrier to provide a sensitive test for the alpha + nucleus optical potential parameter sets. Furthermore, the new high precision angular distributions, together with the data available from the literature were used to study the energy dependence of the locally optimized {\\alpha}+nucleus optical potential in a wide energy region ranging from E_Lab = 27.0 MeV down to 16.1 MeV. The potentials under study are a basic prerequisite for the prediction of alpha-induced reaction cross sections and thus, for the calculation of stellar reaction rates used for the astrophysical gamma process. Therefore, statistical model predictions using as input the optical potentials discussed in the present work are compared to the available 106Cd + alpha cross section data.

  3. Addition and recombination reactions of unsaturated radicals using a novel laser kinetics spectrometer

    E-Print Network [OSTI]

    Ismail, Huzeifa

    2008-01-01

    This thesis describes the construction of a novel, low-noise laser kinetics spectrometer. A quasi-CW (picosecond pulse), tunable Ti:Sapphire laser is used to detect various transient species in laser flash photolysis ...

  4. Measurement of the Translational Energy of Ions with a Time?of?Flight Mass Spectrometer

    E-Print Network [OSTI]

    Franklin, J. L.; Hierl, Peter M.; Whan, David A.

    1967-01-01

    A mathematical analysis of peak shapes in a Bendix time?of?flight mass spectrometer shows that ions formed with excess translational energy exhibit considerable peak broadening. A method is developed by which this translational ...

  5. Development of a TIM-based, flexible, broadband two-crystal spectromet...

    Office of Scientific and Technical Information (OSTI)

    two-crystal spectrometer Authors: Steel, A B ; Dunn, J ; Emig, J ; Beiersdorfer, P ; Brown, G V ; Shepherd, R ; Marley, E V ; Hoarty, D J Publication Date: 2014-05-30 OSTI...

  6. A simple scanning spectrometer based on a stretchable elastomeric reflective grating

    SciTech Connect (OSTI)

    Ghisleri, C.; Milani, P., E-mail: paolo.milani@mi.infn.it [CIMAINA and Dipartimento di Fisica, Universitŕ di Milano, via Celoria 16, 20133 Milano (Italy); WISE srl, Piazza Duse 2, 20122 Milano (Italy); Potenza, M. A. C.; Bellacicca, A. [CIMAINA and Dipartimento di Fisica, Universitŕ di Milano, via Celoria 16, 20133 Milano (Italy); Ravagnan, L. [WISE srl, Piazza Duse 2, 20122 Milano (Italy)

    2014-02-10

    We report a scanning optical spectrometer based on the use of a stretchable elastomeric reflective grating. The grating is obtained by supersonic cluster beam implantation of silver nanoparticles on polydimethylsiloxane previously grooved by molding to create a replica of a commercial digital versatile disk grating. The use of a stretchable grating allows the spectrometer spanning the whole optical wavelength range by solely extending the diffraction element by more than 100% of its original dimensions. The stretchable reflective optical grating shows excellent performances and stability upon thousands of stretching cycles. The use of this elastomeric element makes the optical layout and the mechanics of the spectrometer extremely simple and advantageous for those applications where spectral resolution is not a major requirement. As a proof of principle, we present the absorption spectrum of Rhodamine B in solution obtained by our spectrometer and compared to commercial instruments.

  7. Superconducting gamma and fast-neutron spectrometers with high energy resolution

    DOE Patents [OSTI]

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

    2008-11-04

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

  8. Production of A=6,7 Nuclides in the Alpha + Alpha Reaction and Cosmic Ray Nucleosynthesis

    E-Print Network [OSTI]

    David J. Mercer; Sam M. Austin; J. A. Brown; S. A. Danczyk; S. E. Hirzebruck; J. H. Kelley; T. Suomijarvi; D. A. Roberts; T. P Walker

    2001-04-03

    Cross sections for production of 6He, 6Li, 7Li, and 7Be in the alpha+alpha reaction were measured at bombarding energies of 159.3, 279.6, and 619.8 MeV, and are found to decrease rapidly with increasing energy. These cross sections are essential for the calculation of the rate of nucleosynthesis of the lithium isotopes in the cosmic rays and thereby play a key role in our understanding of the synthesis of Li, Be, and B. The results for 6Li differ significantly from the tabulated values commonly used in cosmic-ray production calculations and lead to lower production of 6Li.

  9. Magnetic Stereoscopy

    E-Print Network [OSTI]

    Thomas Wiegelmann; Bernd Inhester

    2006-12-21

    The space mission STEREO will provide images from two viewpoints. An important aim of the STEREO mission is to get a 3D view of the solar corona. We develop a program for the stereoscopic reconstruction of 3D coronal loops from images taken with the two STEREO spacecraft. A pure geometric triangulation of coronal features leads to ambiguities because the dilute plasma emissions complicates the association of features in image 1 with features in image 2. As a consequence of these problems the stereoscopic reconstruction is not unique and multiple solutions occur. We demonstrate how these ambiguities can be resolved with the help of different coronal magnetic field models (potential, linear and non-linear force-free fields). The idea is that, due to the high conductivity in the coronal plasma, the emitting plasma outlines the magnetic field lines. Consequently the 3D coronal magnetic field provides a proxy for the stereoscopy which allows to eliminate inconsistent configurations. The combination of stereoscopy and magnetic modelling is more powerful than one of these tools alone. We test our method with the help of a model active region and plan to apply it to the solar case as soon as STEREO data become available.

  10. Alpha resonant scattering for astrophysical reaction studies

    SciTech Connect (OSTI)

    Yamaguchi, H.; Kahl, D.; Nakao, T. [Center for Nuclear Study (CNS), University of Tokyo, RIKEN campus, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Wakabayashi, Y.; Kubano, S. [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hashimoto, T. [Research Center for Nuclear Physics (RCNP), Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Hayakawa, S. [Istituto Nazionale Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), Via S. Sofia 62, 95125 Catania (Italy); Kawabata, T. [Department of Physics, Kyoto University, Kita-Shirakawa, Kyoto 606-8502 (Japan); Iwasa, N. [Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578 (Japan); Teranishi, T. [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Kwon, Y. K. [Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yuseong-gu, Daejeon 305-811 (Korea, Republic of); Binh, D. N. [30 MeV Cyclotron Center, Tran Hung Dao Hospital, Hoan Kiem District, Hanoi (Viet Nam); Khiem, L. H.; Duy, N. G. [Institute of Physics, Vietnam Academy of Science and Technology, 18 Hong Quoc Viet, Nghia do, Hanoi (Viet Nam)

    2014-05-02

    Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the ? resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of {sup 7}Be+? resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the {sup 7}Be(?,?) reaction, and proposed a new cluster band in {sup 11}C.

  11. Confinement and $?_s$ in a strong magnetic field

    E-Print Network [OSTI]

    Yu. A. Simonov; M. A. Trusov

    2015-04-01

    Hadron decay widths are shown to increase in strong magnetic fields as $\\Gamma (eB) \\sim \\frac{eB}{\\kappa} \\Gamma(0)$. The same mechanism is shown to be present in the production of the sea quark pair inside the confining string, which decreases the string tension with the growing $eB$ parallel to the string . On the other hand, the average energy of the $q\\bar q$ holes in the string world sheet increases, when the direction of $\\mathbf{B}$ is perpendicular to the sheet. These two effects stipulate the spectacular picture of the $\\mathbf{B}$ dependent confinement and $\\alpha_s$, discovered on the lattice.

  12. Chapter III Physics results of AMS-01

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    Collaboration Abstract The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during the Veto Counters were rejected. The detector performance as well as temperature and magnetic field were-beam test results. The photograph (Figure 25) shows AMS-01 spectrometer being rotated to one of the 600

  13. Performance checks with the Alpha Sentry CAM

    SciTech Connect (OSTI)

    Rodgers, J.C.

    1994-08-01

    Before a CAM is put into service, it must be calibrated. The flow meter and detector must be calibrated with an external flow meter to provide accurate flow data, and the detector must be calibrated to produce accurate DPM data. Both flow and DPM data enter into the calculation of the Derived Air Concentration exposure (DAC-hr) by the CAM software. The focus of this report is on methods for checking that the DAC-hr alarm functionality has been properly calibrated and available in installed CAM instruments. The process begins with detector calibration. In order to calibrate the detector, the Alpha Sentry CAM is placed in an off-line calibration mode and detector efficiency calibration is selected. The user is prompted to enter the calibration source DPM and place the source in the CAM head. Upon latching the filter door with the source in place, a count is automatically initiated and completed. From the count data and the user entered DPM data, an efficiency is determined in the Alpha Sentry Manager (ASM) and stored in non-volatile memory in the CAM head electronics. This source is typically a plated {sup 239}Pu or {sup 241}Am source diffused into a stainless steel planchet.

  14. GHRS Observations of the Lyman alpha Forest

    E-Print Network [OSTI]

    Simon L. Morris

    1996-10-28

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

  15. MFTF-. cap alpha. + T progress report

    SciTech Connect (OSTI)

    Nelson, W.D.

    1985-04-01

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

  16. Including stereoscopic information in the reconstruction of coronal magnetic fields

    E-Print Network [OSTI]

    T. Wiegelmann; T. Neukirch

    2008-01-23

    We present a method to include stereoscopic information about the three dimensional structure of flux tubes into the reconstruction of the coronal magnetic field. Due to the low plasma beta in the corona we can assume a force free magnetic field, with the current density parallel to the magnetic field lines. Here we use linear force free fields for simplicity. The method uses the line of sight magnetic field on the photosphere as observational input. The value of $\\alpha$ is determined iteratively by comparing the reconstructed magnetic field with the observed structures. The final configuration is the optimal linear force solution constrained by both the photospheric magnetogram and the observed plasma structures. As an example we apply our method to SOHO MDI/EIT data of an active region. In the future it is planned to apply the method to analyse data from the SECCHI instrument aboard the STEREO mission.

  17. Lyman alpha Absorption Systems and the Intergalactic Medium

    E-Print Network [OSTI]

    George Efstathiou; Joop Schaye; Tom Theuns

    2000-04-10

    The last few years have seen a dramatic improvement in our understanding of the origin of Lyman alpha absorption systems. Hydrodynamic numerical simulations of cold dark matter dominated universes have shown that the many properties of the Lyman alpha absorption systems can be explained by a photoionized, space-filling, intergalactic medium. Lyman alpha lines offer promising probes of the photoionizing background, the amplitude of the mass fluctuations at high redshift and the evolution of the equation of state of the intergalactic medium.

  18. Scintillation of thin tetraphenyl butadiene films under alpha particle excitation

    E-Print Network [OSTI]

    Pollmann, Tina; Ku?niak, Marcin

    2010-01-01

    The alpha induced scintillation of the wavelength shifter 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) was studied to improve the understanding of possible surface alpha backgrounds in the DEAP dark matter search experiment. We found that vacuum deposited thin TPB films emit 882 +/-210 photons per MeV under alpha particle excitation. The scintillation pulse shape consists of a double exponential decay with lifetimes of 11 +/-5 ns and 275 +/-10ns.

  19. Two- and three-alpha systems with nonlocal potential

    E-Print Network [OSTI]

    Z. Papp; S. Moszkowski

    2008-03-26

    Two body data alone cannot determine the potential uniquely, one needs three-body data as well. A method is presented here which simultaneously fits local or nonlocal potentials to two-body and three-body observables. The interaction of composite particles, due to the Pauli effect and the indistinguishability of the constituent particles, is genuinely nonlocal. As an example, we use a Pauli-correct nonlocal fish-bone type optical model for the $\\alpha-\\alpha$ potential and derive the fitting parameters such that it reproduces the two-$\\alpha$ and three-$\\alpha$ experimental data.

  20. Penguin pollution estimates relevant for phi_2/alpha extraction

    E-Print Network [OSTI]

    Jure Zupan

    2007-08-16

    A review of methods to extract the standard CKM unitarity triangle angle alpha is provided. The sizes of related theoretical errors are reviewed.

  1. Alpha-particle optical potential proofs at astrophysically relevant energies

    E-Print Network [OSTI]

    M. Avrigeanu; V. Avrigeanu

    2008-11-01

    $(\\alpha,\\gamma)$ and $(\\alpha$,n) reaction cross sections recently measured close to the reaction thresholds are rather well described by a previously developed regional optical potential. Thus, particular features of the $\\alpha$-particle optical potential at energies below the Coulomb barrier, besides parameters describing $\\alpha$-particle elastic scattering at higher energies are confirmed. Additional limitations of similar statistical model calculations for minor reaction channels are shown to be most likely due to an overlooked process or critical values of statistical model parameters around closed nuclear shells.

  2. Magnetic Reconnection

    SciTech Connect (OSTI)

    Masaaki Yamada, Russell Kulsrud and Hantao Ji

    2009-09-17

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

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

    E-Print Network [OSTI]

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

    2007-05-30

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

  4. Patterned Magnetic Nanostructures and Quantized Magnetic Disks

    E-Print Network [OSTI]

    -increasing demands in data storage and to new applications of magnetic devices in the field of sensors. NewPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper, opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra

  5. Properties of solar polar coronal plumes constrained by Ultraviolet Coronagraph Spectrometer data

    E-Print Network [OSTI]

    N. -E. Raouafi; J. W. Harvey; S. K. Solanki

    2007-03-29

    We investigate the plasma dynamics (outflow speed and turbulence) inside polar plumes. We compare line profiles (mainly of \\ion{O}{6}) observed by the UVCS instrument on SOHO at the minimum of solar cycle 22-23 with model calculations. We consider Maxwellian velocity distributions with different widths in plume and inter-plume regions. Electron densities are assumed to be enhanced in plumes and to approach inter-plume values with increasing height. Different combinations of the outflow and turbulence velocity in the plume regions are considered. We compute line profiles and total intensities of the \\ion{H}{1} Ly$\\alpha$ and the \\ion{O}{6} doublets. The observed profile shapes and intensities are reproduced best by a small solar wind speed at low altitudes in plumes that increases with height to reach ambient inter-plume values above roughly 3-4 $R_\\sun$ combined with a similar variation of the width of the velocity distribution of the scattering atoms/ions. We also find that plumes very close to the pole give narrow profiles at heights above 2.5 $R_\\sun$, which are not observed. This suggests a tendency for plumes to be located away from the pole. We find that the inclusion of plumes in the model computations provides an improved correspondence with the observations and confirms previous results showing that published UVCS observations in polar coronal holes can be roughly reproduced without the need for large temperature anisotropy. The latitude distributions of plumes and magnetic flux distributions are studied by analyzing data from different instruments on SOHO and with SOLIS.

  6. Effects of alpha beam on the parametric decay of a parallel propagating circularly polarized Alfven wave: Hybrid simulations

    SciTech Connect (OSTI)

    Gao, Xinliang; Lu, Quanming; Tao, Xin; Hao, Yufei; Wang, Shui

    2013-09-15

    Alfven waves with a finite amplitude are found to be unstable to a parametric decay in low beta plasmas. In this paper, the parametric decay of a circularly polarized Alfven wave in a proton-electron-alpha plasma system is investigated with one-dimensional (1-D) hybrid simulations. In cases without alpha particles, with the increase of the wave number of the pump Alfven wave, the growth rate of the decay instability increases and the saturation amplitude of the density fluctuations slightly decrease. However, when alpha particles with a sufficiently large bulk velocity along the ambient magnetic field are included, at a definite range of the wave numbers of the pump wave, both the growth rate and the saturation amplitude of the parametric decay become much smaller and the parametric decay is heavily suppressed. At these wave numbers, the resonant condition between the alpha particles and the daughter Alfven waves is satisfied, therefore, their resonant interactions might play an important role in the suppression of the parametric decay instability.

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

    SciTech Connect (OSTI)

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

    2013-02-15

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

  8. Lyman Alpha Absorption in The Cosmic Web

    E-Print Network [OSTI]

    J. Richard Bond; James W. Wadsley

    1997-10-10

    We describe large scale structure at high redshift in terms of the Cosmic Web picture for {S,Lambda,O,H}CDM models: how galactic-scale ``peak-patches'', filaments and membranes create an interconnected intergalactic medium. The ideas are applied to our Ly$\\alpha$ forest simulations of ``shear-field patches''. We discuss simulation method and design, resolution dependence, the statistical combination of patches, UV flux scaling, and whether filtered Zel'dovich maps are useful. The response to changes in power spectrum shape and amplitude, and in cosmological parameters, is described. We also show Omega_b h^2 derived from UV rescaling is overestimated if the resolution is not adequate.

  9. Synthesis of alpha-amino acids

    DOE Patents [OSTI]

    Davis, J.W. Jr.

    1983-01-25

    A method is described for synthesizing alpha amino acids proceeding through novel intermediates of the formulas: R[sub 1]R[sub 2]C(OSOCl)CN, R[sub 1]R[sub 2]C(Cl)CN and [R[sub 1]R[sub 2]C(CN)O][sub 2]SO wherein R[sub 1] and R[sub 2] are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art. No Drawings

  10. Constraining Reionization with Lyman Alpha Emitting Galaxies

    E-Print Network [OSTI]

    Dijkstra, Mark

    2015-01-01

    Neutral diffuse intergalactic gas that existed during the Epoch of Reionization (EoR) suppresses Lyman Alpha (Lya) flux emitted by background galaxies. In this chapter I summarise the increasing observational support for the claim that Lya photons emitted by galaxies at z>6 are suppressed by intervening HI gas. I describe key physical processes that affect Lya transfer during the EoR. I argue that in spite of the uncertainties associated with this complex multiscale problem, the data on Lya emitting galaxies at z=0-6 strongly suggests that the observed reduction in Lya flux from galaxies at z>6 is due to additional intervening HI gas. The main question is what fraction of this additional HI gas is in the diffuse neutral IGM. I summarise how future surveys on existing and upcoming instruments are expected to reduce existing observational uncertainties enormously. With these improved data we will likely be able to nail down reionization with Lya emitting galaxies.

  11. PPPL3160 Preprint Date: April 1996, UC420 Observations of Neutral Beam and ICRF Tail Ion Losses Due to

    E-Print Network [OSTI]

    act as magnetic spectrometers, dispersing fast ions onto a scintillator, depending upon, ICRF heating tail ions, and alpha particles all heat the plasma and may all be lost through processes the toroidal Alfvén eigenmode (TAE), the kinetic balloon­ ing mode (KBM), alpha driven sawteeth, alpha driven

  12. Signatures of reionization on Lyman alpha emitters

    E-Print Network [OSTI]

    Pratika Dayal; Andrea Ferrara; Simona Gallerani

    2008-07-23

    We use a semi-analytic model of Lyman alpha emitters (LAEs) to constrain the reionization history. By considering two physically motivated scenarios in which reionization ends either early (ERM, z_i ~ 7) or late (LRM, z_i ~ 6), we fix the global value of the IGM neutral fraction (e.g. chi_{HI}=3 times 10^{-4}, 0.15 at z=6.56 for the ERM and LRM, respectively) leaving only the star formation efficiency and the effective escape fraction of Lya photons as free parameters. The ERM fits the observed LAE luminosity function (LF) at z=5.7 and 6.56 requiring no redshift evolution or mass dependence of the star formation efficiency, and LAE star formation rates (SFR) of 3-103 solar masses/year, contributing approximately 8% of the cosmic SFR density at z=5.7. The LRM requires a physically uncomfortable drop of approximately 4.5 times in the SFR of the emitters from z=6.5 to 5.7. Thus, the data seem to imply that the Universe was already highly ionized at z=6.56. The mass-dependent Lya transmissivity is between 0.36-0.51 (ERM) and less than 0.26 (LRM) at z=6.56. The LF data at z=4.5 imply an extra Lya line damping factor of approximately 0.25 possibly due to dust; the presence of a (clumpy) dust component with E(B-V) ~ 0.28 is also required to reproduce the observed large Lya equivalent widths at the same redshift. Additional useful information can be extracted from the line profile (weighted) skewness, found to be S_W=10-17 Angstrom for the two reionization models, which shows an interesting L_alpha-chi_{HI} anti-correlation, holding under the model assumptions. The shortcomings of the model and strategies to overcome them are discussed.

  13. AMS Transition Radiation Detector 4-Layer Prototype and Gas System Tests

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    quality and tests performed on a TRD 4-layer prototype will be discussed. 1 Introduction Alpha Magnetic Spectrometer (AMS) [1] is a high energy physics experiment that will be located on the International Space

  14. Dynamic Measurements on a Star Tracker Prototype of AMS Using Fiber Optic Sensors

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    ABSTRACT An aluminum prototype of the Amica Star Tracker Support (ASTS) of the AMS_02 (Alpha Magnetic Spectrometer) experiment has been instrumented with two Fiber Bragg Gratings (FBGs). AMS_02 is a 7 tons

  15. In proceedings of the International Conference on Robots and Systems (IROS), Pittsburgh PA, August 5-9 1995. Mobile Robot Localization

    E-Print Network [OSTI]

    Volpe, Richard

    , taking pictures and positioning an alpha/proton/x- ray spectrometer against designated soil and rocks 2 readings cannot be used since Mars has no appreciable magnetic eld 5]. The near-lander behavior

  16. Space Shuttle Program Status

    E-Print Network [OSTI]

    Waliser, Duane E.

    Payload: 36th ISS flight (ULF6), EXPRESS Logistics Carrier 3 (ELC3), Alpha Magnetic Spectrometer (AMS;8 Transition #12;9 Major Space Shuttle Program Facilities Reusable Solid Rocket Motor ATK Thiokol Propulsion

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

    E-Print Network [OSTI]

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

    2013-06-17

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

  18. A solenoidal electron spectrometer for a precision measurement of the neutron $\\beta$-asymmetry with ultracold neutrons

    E-Print Network [OSTI]

    Plaster, B; Filippone, B W; Harrison, D; Hsiao, J; Ito, T M; Liu, J; Martin, J W; Tipton, B; Yuan, J

    2008-01-01

    We describe an electron spectrometer designed for a precision measurement of the neutron $\\beta$-asymmetry with spin-polarized ultracold neutrons. The spectrometer consists of a 1.0-Tesla solenoidal field with two identical multiwire proportional chamber and plastic scintillator electron detector packages situated within 0.6-Tesla field-expansion regions. Select results from performance studies of the spectrometer with calibration sources are reported.

  19. Standard test method for isotopic analysis of uranium hexafluoride by double standard single-collector gas mass spectrometer method

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This is a quantitative test method applicable to determining the mass percent of uranium isotopes in uranium hexafluoride (UF6) samples with 235U concentrations between 0.1 and 5.0 mass %. 1.2 This test method may be applicable for the entire range of 235U concentrations for which adequate standards are available. 1.3 This test method is for analysis by a gas magnetic sector mass spectrometer with a single collector using interpolation to determine the isotopic concentration of an unknown sample between two characterized UF6 standards. 1.4 This test method is to replace the existing test method currently published in Test Methods C761 and is used in the nuclear fuel cycle for UF6 isotopic analyses. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro...

  20. Magnetic Field Rotations in the Solar Wind at Kinetic Scales

    E-Print Network [OSTI]

    Chen, C H K; Burgess, D; Horbury, T S

    2015-01-01

    The solar wind magnetic field contains rotations at a broad range of scales, which have been extensively studied in the MHD range. Here we present an extension of this analysis to the range between ion and electron kinetic scales. The distribution of rotation angles was found to be approximately log-normal, shifting to smaller angles at smaller scales almost self-similarly, but with small, statistically significant changes of shape. The fraction of energy in fluctuations with angles larger than $\\alpha$ was found to drop approximately exponentially with $\\alpha$, with e-folding angle $9.8^\\circ$ at ion scales and $0.66^\\circ$ at electron scales, showing that large angles ($\\alpha > 30^\\circ$) do not contain a significant amount of energy at kinetic scales. Implications for kinetic turbulence theory and the dissipation of solar wind turbulence are discussed.

  1. Method for using a yeast alpha-amylase promoter

    DOE Patents [OSTI]

    Gao, Johnway (Richland, WA); Skeen, Rodney S. (Pendleton, OR); Hooker, Brian S. (Kennewick, WA); Anderson, Daniel B. (Pasco, WA)

    2003-04-22

    The present invention provides the promoter clone discovery of an alpha-amylase gene of a starch utilizing yeast strain Schwanniomyces castellii. The isolated alpha-amylase promoter is an inducible promoter, which can regulate strong gene expression in starch culture medium.

  2. Generating long streams of $1/f^alpha$ noise

    E-Print Network [OSTI]

    S. Plaszczynski

    2008-07-09

    We review existing methods for generating long streams of 1/f^alpha noise ($0logistic maps, we give hints on how to design generators with $\\alpha>2$. The software is available from http://planck.lal.in2p3.fr/article.php3?id\\_article=8

  3. The origin, evolution and signatures of primordial magnetic fields

    E-Print Network [OSTI]

    Kandaswamy Subramanian

    2015-04-09

    The universe is magnetized on all scales probed so far. On the largest scales, galaxies and galaxy clusters host magnetic fields at the micro Gauss level coherent on scales up to ten kpc. Recent observational evidence suggests that even the intergalactic medium in voids could host a weak $\\sim 10^{-16}$ Gauss magnetic field, coherent on Mpc scales. An intriguing possibility is that these observed magnetic fields are a relic from the early universe, albeit one which has been subsequently amplified and maintained by a dynamo in collapsed objects. We review here the origin, evolution and signatures of primordial magnetic fields. After a brief summary of magnetohydrodynamics in the expanding universe, we turn to magnetic field generation during inflation and other phase transitions. We trace the linear and nonlinear evolution of the generated primordial fields through the radiation era, including viscous effects. Sensitive observational signatures of primordial magnetic fields on the cosmic microwave background, including current constraints from Planck, are discussed. After recombination, primordial magnetic fields could strongly influence structure formation, especially on dwarf galaxy scales. The resulting signatures on reionization, the redshifted 21 cm line, weak lensing and the Lyman-$\\alpha$ forest are outlined. Constraints from radio and $\\gamma$-ray astronomy are summarized. Astrophysical batteries and the role of dynamos in reshaping the primordial field are briefly considered. The review ends with some final thoughts on primordial magnetic fields.

  4. Elastic alpha scattering experiments and the alpha-nucleus optical potential at low energies

    E-Print Network [OSTI]

    P. Mohr; G. G. Kiss; Zs. Fülöp; D. Galaviz; Gy. Gyürky; E. Somorjai

    2012-12-12

    High precision angular distribution data of ($\\alpha$,$\\alpha$) elastic scattering are presented for the nuclei $^{89}$Y, $^{92}$Mo, $^{106,110,116}$Cd, $^{112,124}$Sn, and $^{144}$Sm at energies around the Coulomb barrier. Such data with small experimental uncertainties over the full angular range (20-170 degrees) are the indispensable prerequisite for the extraction of local optical potentials and for the determination of the total reaction cross section $\\sigma_{\\rm{reac}}$. A systematic fitting procedure was applied to the presented experimental scattering data to obtain comprehensive local potential parameter sets which are composed of a real folding potential and an imaginary potential of Woods-Saxon surface type. The obtained potential parameters were used in turn to construct a new systematic $\\alpha$-nucleus potential with very few parameters. Although this new potential cannot reproduce the angular distributions with the same small deviations as the local potential, the new potential is able to predict the total reaction cross sections for all cases under study.

  5. A simple procedure to prepare spherical {alpha}-alumina powders

    SciTech Connect (OSTI)

    Liu Hongyu [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Ning Guiling [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)], E-mail: ninggl@dlut.edu.cn; Gan Zhihong; Lin Yuan [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)

    2009-04-02

    Spherical {alpha}-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of {alpha}-alumina powders. The precursors crystallized to {gamma}-alumina at 1000 deg. C and converted to {alpha}-alumina at 1150 deg. C without intermediate phases. The particle morphology of precursor was retained after it crystallized to {alpha}-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to {alpha}-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products.

  6. Superconducting Magnet Division

    E-Print Network [OSTI]

    Gupta, Ramesh

    Superconducting Magnet Division Permanent Magnet Designs with Large Variations in Field Strength the residual field of the magnetized bricks by concentrating flux lines at the iron pole. Low Field Design Medium Field Design Superconducting Magnet Division Dipole and Quadrupole Magnets for RHIC e

  7. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01

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

  8. A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA and the NIF

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

    Zylstra, A. B.; Gatu Johnson, M.; Frenje, J. A.; Seguin, F. H.; Rinderknecht, H. G.; Rosenberg, M. J.; Sio, H. W.; Li, C. K.; Petrasso, R. D.; McCluskey, M.; Mastrosimone, D.; Glebov, V. Yu.; Forrest, C.; Stoeckl, C.; Sangster, T. C.

    2014-06-01

    A compact spectrometer for measurements of the primary deuterium-tritium neutron spectrum has been designed and implemented on the OMEGA laser facility [T. Boehly et al. , Opt. Commun.133, 495 (1997)]. This instrument uses the recoil spectrometry technique, where neutrons produced in an implosion elastically scatter protons in a plastic foil, which are subsequently detected by a proton spectrometer. This diagnostic is currently capable of measuring the yield to ~±10% accuracy, and mean neutron energy to ~±50 keV precision. As these compact spectrometers can be readily placed at several locations around an implosion, effects of residual fuel bulk flows during burn can be measured. Future improvements to reduce the neutron energy uncertainty to ±15-20 keV are discussed, which will enable measurements of fuel velocities to an accuracy of ~±25-40 km/s.

  9. A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA and the NIF

    SciTech Connect (OSTI)

    Zylstra, A. B., E-mail: zylstra@mit.edu; Gatu Johnson, M.; Frenje, J. A.; Séguin, F. H.; Rinderknecht, H. G.; Rosenberg, M. J.; Sio, H. W.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); McCluskey, M.; Mastrosimone, D.; Glebov, V. Yu.; Forrest, C.; Stoeckl, C.; Sangster, T. C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

    2014-06-15

    A compact spectrometer for measurements of the primary deuterium-tritium neutron spectrum has been designed and implemented on the OMEGA laser facility [T. Boehly et al., Opt. Commun. 133, 495 (1997)]. This instrument uses the recoil spectrometry technique, where neutrons produced in an implosion elastically scatter protons in a plastic foil, which are subsequently detected by a proton spectrometer. This diagnostic is currently capable of measuring the yield to ?±10% accuracy, and mean neutron energy to ?±50 keV precision. As these compact spectrometers can be readily placed at several locations around an implosion, effects of residual fuel bulk flows during burn can be measured. Future improvements to reduce the neutron energy uncertainty to ±15?20 keV are discussed, which will enable measurements of fuel velocities to an accuracy of ?±25?40 km/s.

  10. A compact stilbene crystal neutron spectrometer for EAST D-D plasma neutron diagnostics

    SciTech Connect (OSTI)

    Zhang Xing; Yuan Xi; Xie Xufei; Chen Zhongjing; Peng Xingyu; Chen Jinxiang; Zhang Guohui; Li Xiangqing; Fan Tieshuan [School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Chengfu Road 201, 100871 Beijing (China); Zhong Guoqiang; Hu Liqun; Wan Baonian [Institute of Plasma Physics, Chinese Academy of Sciences, PO Box 1126, 230031 Hefei, Anhui (China)

    2013-03-15

    A new compact stilbene crystal neutron spectrometer has been investigated and applied in the neutron emission spectroscopy on the EAST tokamak. A new components analysis method is presented to study the anisotropic light output in the stilbene crystal detector. A Geant4 code was developed to simulate the neutron responses in the spectrometer. Based on both the optimal light output function and the fitted pulse height resolution function, a reliable neutron response matrix was obtained by Geant4 simulations and validated by 2.5 MeV and 14 MeV neutron measurements at a 4.5 MV Van de Graaff accelerator. The spectrometer was used to diagnose the ion temperature in plasma discharges with lower hybrid wave injection and ion cyclotron resonance heating on the EAST tokamak.

  11. Spectrometer for Hard X-Ray Free Electron Laser Based on Diffraction Focusing

    E-Print Network [OSTI]

    Kohn, V G; Vartanyants, I A

    2012-01-01

    X-ray free electron lasers (XFELs) generate sequences of ultra-short, spatially coherent pulses of x-ray radiation. We propose the diffraction focusing spectrometer (DFS), which is able to measure the whole energy spectrum of the radiation of a single XFEL pulse with an energy resolution of $\\Delta E/E\\approx 2\\times 10^{-6}$. This is much better than for most modern x-ray spectrometers. Such resolution allows one to resolve the fine spectral structure of the XFEL pulse. The effect of diffraction focusing occurs in a single crystal plate due to dynamical scattering, and is similar to focusing in a Pendry lens made from the metamaterial with a negative refraction index. Such a spectrometer is easier to operate than those based on bent crystals. We show that the DFS can be used in a wide energy range from 5 keV to 20 keV.

  12. Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report

    SciTech Connect (OSTI)

    NONE

    1998-02-15

    A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.

  13. Enhancing Low-Cost Ozone Spectrometers to Measure Mesospheric Winds and Tides

    E-Print Network [OSTI]

    Alam, O B

    2015-01-01

    Ground-based spectrometers have been developed to measure the concentration, velocity, and temperature of ozone in the mesosphere and lower thermosphere (MLT) using low-cost satellite television electronics to observe the 11.072 GHz spectral line of ozone. A two-channel spectrometer has been engineered to yield various performance improvements, including a doubling of the signal-to-noise ratio, improved data processing efficiency, and lower power consumption at 15 W. Following 2009 and 2012 observations of the seasonal and diurnal variations in ozone concentration near the mesopause, the ozone line was observed at an altitude near 95 km and latitude of 38 degrees north using three single-channel spectrometers located at the MIT Haystack Observatory (Westford, MA), Chelmsford High School (Chelmsford, MA), and Union College (Schenectady, NY) pointed south at 8 degrees. Observations from 2009 through 2014 are used to derive the nightly-averaged seasonal variation in meridional velocity, as well as the seasonally...

  14. A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA and the NIF

    SciTech Connect (OSTI)

    Zylstra, A. B.; Gatu Johnson, M.; Frenje, J. A.; Seguin, F. H.; Rinderknecht, H. G.; Rosenberg, M. J.; Sio, H. W.; Li, C. K.; Petrasso, R. D.; McCluskey, M.; Mastrosimone, D.; Glebov, V. Yu.; Forrest, C.; Stoeckl, C.; Sangster, T. C.

    2014-06-01

    A compact spectrometer for measurements of the primary deuterium-tritium neutron spectrum has been designed and implemented on the OMEGA laser facility. This instrument uses the recoil spectrometry technique, where neutrons produced in an implosion elastically scatter protons in a plastic foil, which are subsequently detected by a proton spectrometer. This diagnostic is currently capable of measuring the yield to ~±10% accuracy, and mean neutron energy to ~±50 keV precision. As these compact spectrometers can be readily placed at several locations around an implosion, effects of residual fuel bulk flows during burn can be measured. Future improvements to reduce the neutron energy uncertainty to ±15-20 keV are discussed, which will enable measurements of fuel velocities to an accuracy of ~±25-40 km/s.

  15. Quantum states of neutrons in the gravitational and centrifugal potentials in a new GRANIT spectrometer

    ScienceCinema (OSTI)

    None

    2011-10-06

    We will discuss the scientific program to be studied in a new gravitational spectrometer GRANIT in a broad context of quantum states (quantum behaviour) of ultracold neutrons (UCN) in gravitational [1] and centrifugal [2] potentials, as well as applications of these phenomena/spectrometer to various domains of physics, ranging from studies of fundamental short-range interactions and symmetries to neutron quantum optics and reflectometry using UCN. All these topics, as well as related instrumental and methodical developments have been discussed during dedicated GRANIT-2010 Workshop [3]. The GRANIT spectrometer has been recently installed at the Institut Laue-Langevin, Grenoble, France [4] and could become operational in near future. 1. V.V. Nesvizhevsky et al (2002), Nature 415, 297. 2. V.V. Nesvizhevsky et al (2010), Nature Physics 6, 114. 3. GRANIT-2010, Les Houches, 14-19 february 2010. 4. M. Kreuz et al (2009), NIM 611, 326.

  16. A compact neutron spectrometer for characterizing inertial confinement fusion implosions at OMEGA and the NIF

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

    Zylstra, A. B.; Gatu Johnson, M.; Frenje, J. A.; Séguin, F. H.; Rinderknecht, H. G.; Rosenberg, M. J.; Sio, H. W.; Li, C. K.; Petrasso, R. D.; McCluskey, M.; et al

    2014-06-04

    A compact spectrometer for measurements of the primary deuterium-tritium neutron spectrum has been designed and implemented on the OMEGA laser facility. This instrument uses the recoil spectrometry technique, where neutrons produced in an implosion elastically scatter protons in a plastic foil, which are subsequently detected by a proton spectrometer. This diagnostic is capable of measuring the yield to ~±10% accuracy, and mean neutron energy to ~±50 keV precision. As these compact spectrometers can be readily placed at several locations around an implosion, effects of residual fuel bulk flows during burn can be measured. Future improvements to reduce the neutron energymore »uncertainty to ±15-20 keV are discussed, which will enable measurements of fuel velocities to an accuracy of ~±25-40 km/s.« less

  17. Simonetta Gentile Rencontres du Vietnam,Hanoi 2004

    E-Print Network [OSTI]

    Roma "La Sapienza", Universitŕ di

    Simonetta Gentile Rencontres du Vietnam,Hanoi 2004 Cosmic Ray Physics with the Alpha Magnetic t Large acceptance ~0.5m2sr. #12;Simonetta Gentile Rencontres du Vietnam,Hanoi 2004 The Alpha Magnetic Spectrometer Simonetta Gentile Universitŕ di Roma La Sapienza, INFN on behalf of AMS Collaboration #12

  18. Foil cycling technique for the VESUVIO spectrometer operating in the resonance detector configuration

    SciTech Connect (OSTI)

    Schooneveld, E. M.; Mayers, J.; Rhodes, N. J.; Pietropaolo, A.; Andreani, C.; Senesi, R.; Gorini, G.; Perelli-Cippo, E.; Tardocchi, M.

    2006-09-15

    This article reports a novel experimental technique, namely, the foil cycling technique, developed on the VESUVIO spectrometer (ISIS spallation source) operating in the resonance detector configuration. It is shown that with a proper use of two foils of the same neutron absorbing material it is possible, in a double energy analysis process, to narrow the width of the instrumental resolution of a spectrometer operating in the resonance detector configuration and to achieve an effective subtraction of the neutron and gamma backgrounds. Preliminary experimental results, obtained from deep inelastic neutron scattering measurements on lead, zirconium hydride, and deuterium chloride samples, are presented.

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

    SciTech Connect (OSTI)

    Rukhadze, Ekaterina [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a Collaboration: OBELIX Collaboration; SuperNEMO Collaboration

    2013-12-30

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

  20. Next-Generation Germanium Spectrometer Background Reduction Techniques at 2 MeV

    SciTech Connect (OSTI)

    Brodzinski, Ronald L.

    2005-04-01

    The Majorana project, a next-generation 76Ge neutrinoless double-beta decay experiment being undertaken by a large international collaboration, has the goal of measuring the neutrinoless double-beta decay rate by observing monochromatic events at 2039 keV in 500 kg of isotopically enriched 76Ge gamma-ray spectrometers. In order to achieve the desired sensitivity limit, the background in the 2037-2041 keV region must be reduced to <1 event per year in the entire germanium array. The effects of various background reduction techniques, and the combination thereof, to produce a huge 76Ge spectrometer array with virtually zero background are discussed.

  1. Thalamocortical Mechanisms for the Anteriorization of Alpha Rhythms during Propofol-Induced Unconsciousness

    E-Print Network [OSTI]

    Vijayan, Sujith

    As humans are induced into a state of general anesthesia via propofol, the normal alpha rhythm (8–13 Hz) in the occipital cortex disappears and a frontal alpha rhythm emerges. This spatial shift in alpha activity is called ...

  2. Nanostructured magnetic materials

    E-Print Network [OSTI]

    Chan, Keith T.

    2011-01-01

    Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

  3. CONSTRAINING PRIMORDIAL MAGNETIC FIELDS THROUGH LARGE-SCALE STRUCTURE

    SciTech Connect (OSTI)

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

    2013-06-10

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

  4. Magnets and Power Supplies

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

    Up: APS Storage Ring Parameters Previous: Longitudinal bunch profile and Magnets and Power Supplies Dipole Magnets and Power Supplies Value Dipole Number 80+1 No. of power...

  5. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01

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

  6. Thick-Target Neutron Yield from the 19F(alpha,n) Reaction

    E-Print Network [OSTI]

    E. B. Norman; T. E. Chupp; K. T. Lesko; G. L. Woodruff; P. J. Grant

    2015-01-10

    Thick-target neutron yields from the 19F(alpha,n) reaction are reported for E(alpha) = 3.5 - 10.0 MeV.

  7. New experimental limits on the alpha decays of lead isotopes

    E-Print Network [OSTI]

    J. W. Beeman; F. Bellini; L. Cardani; N. Casali; S. Di Domizio; E. Fiorini; L. Gironi; S. S. Nagorny; S. Nisi; F. Orio; L. Pattavina; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; C. Tomei; M. Vignati

    2012-12-12

    For the first time a PbWO4 crystal was grown using ancient Roman lead and it was run as a cryogenic detector. Thanks to the simultaneous and independent read-out of heat and scintillation light, the detector was able to discriminate beta/gamma interactions with respect to alpha particles down to low energies. New more stringent limits on the alpha decays of the lead isotopes are presented. In particular a limit of T_{1/2} > 1.4*10^20 y at a 90% C.L. was evaluated for the alpha decay of 204Pb to 200Hg.

  8. Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN

    E-Print Network [OSTI]

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

    2008-05-27

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

  9. Selective flow path alpha particle detector and method of use

    DOE Patents [OSTI]

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

    2002-01-01

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

  10. Planetary and Space Science 55 (2007) 494502 The D-CIXS X-ray spectrometer on the SMART-1 mission

    E-Print Network [OSTI]

    Wieczorek, Mark

    2007-01-01

    Planetary and Space Science 55 (2007) 494­502 The D-CIXS X-ray spectrometer on the SMART-1 mission 2006; accepted 19 August 2006 Available online 17 January 2007 Abstract The SMART-1 mission has recently arrived at the Moon. Its payload includes D-CIXS, a compact X-ray spectrometer. SMART-1

  11. Retrieval of subpixel snow-covered area and grain size from imaging spectrometer data

    E-Print Network [OSTI]

    Dozier, Jeff

    Retrieval of subpixel snow-covered area and grain size from imaging spectrometer data Thomas H 2002 Abstract We describe and validate an automated model that retrieves subpixel snow-covered area multiple endmember spectral mixtures with a spectral library of snow, vegetation, rock, and soil. We derive

  12. X-ray Astronomy with CCDs: Calibration of the Advanced CCD Imaging Spectrometer and

    E-Print Network [OSTI]

    efficiency of CCDs used as ref- erence standards for ACIS characterization. I also discuss a novel "mesh Imaging Spectrometer (ACIS), one of the two primary focal plane instruments on the Chandra X inside certain regions of the ACIS detectors. Guided by the results of the mesh experiments, I performed

  13. X-ray Astronomy with CCDs: Calibration of the Advanced CCD Imaging Spectrometer and

    E-Print Network [OSTI]

    Ćciency of CCDs used as ref- erence standards for ACIS characterization. I also discuss a novel \\mesh" technique I of the Advanced CCD Imaging Spectrometer (ACIS), one of the two primary focal plane instruments on the Chandra X certain regions of the ACIS detectors. Guided by the results of the mesh experiments, I performed

  14. Remote sensing of surface pressure on Mars with the Mars Express/OMEGA spectrometer

    E-Print Network [OSTI]

    Spiga, Aymeric

    - surement of surface pressure from orbit, as is done for temperature or water vapor [Smith, 2006]. [4Remote sensing of surface pressure on Mars with the Mars Express/OMEGA spectrometer: 2 November 2006; revised 6 July 2007; accepted 7 August 2007; published 30 August 2007. [1] Surface pressure

  15. UV-light microscope: improvements in optical imaging for a secondary ion mass spectrometer

    E-Print Network [OSTI]

    Meyers, Stephen R.

    UV-light microscope: improvements in optical imaging for a secondary ion mass spectrometer Noriko T­10 mm. However, the original reflected light microscope of the CAMECA IMS 1280 SIMS had an optical at the mm scale. We modified the optical microscope to use ultraviolet (UV) light illumination and UV

  16. Laser desorption time-of-flight mass spectrometer DNA analyzer. Final report

    SciTech Connect (OSTI)

    Chen, C.H.W.; Martin, S.A.

    1997-02-01

    The objective of this project is the development of a laser desorption time-of-flight mass spectrometer DNA analyzer which can be broadly used for biomedical research. Tasks include: pulsed ion extraction to improve resolution; two-component matrices to enhance ionization; and solid phase DNA purification.

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

    E-Print Network [OSTI]

    Goodsell, Alison

    2012-10-19

    and U. Using the flat quartz-crystal x-ray spectrometer and customized collimation system, the Monte Carlo N-Particle (MCNP) simulations showed the 103.7 keV Pu x-ray peak signal-to-noise ratio improved by a factor of 13 and decreased the percent error...

  18. Terahertz spectroscopy with a holographic Fourier transform spectrometer plus array detector using coherent synchrotron radiation

    SciTech Connect (OSTI)

    Nikolay I. Agladz, John Klopf, Gwyn Williams, Albert J. Sievers

    2010-06-01

    By use of coherent terahertz synchrotron radiation, we experimentally tested a holographic Fourier transform spectrometer coupled to an array detector to determine its viability as a spectral device. Somewhat surprisingly, the overall performance strongly depends on the absorptivity of the birefringent lithium tantalate pixels in the array detector.

  19. Airborne Fourier transform spectrometer observations in support of EOS Aura validation

    E-Print Network [OSTI]

    ), Microwave Limb Sounder (MLS), and Tropospheric Emission Spectrometer (TES) instruments aboard the EOS Aura measurements of gaseous constituents derived from the absorption of infrared solar radiation by the atmosphere here on comparisons with limb viewing measurements made by the Microwave Limb Sounder (MLS) [Waters et

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

    E-Print Network [OSTI]

    M. K. Georgoulis; Barry J. LaBonte

    2007-06-27

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

  1. A New Interpretation of Alpha-particle-driven Instabilities in Deuterium-Tritium Experiments on the Tokamak Fusion Test Reactor

    SciTech Connect (OSTI)

    R. Nazikian; G.J. Kramer; C.Z. Cheng; N.N. Gorelenkov; H.L. Berk; S.E. Sharapov

    2003-03-26

    The original description of alpha-particle-driven instabilities in the Tokamak Fusion Test Reactor (TFTR) in terms of Toroidal Alfvin Eigenmodes (TAEs) remained inconsistent with three fundamental characteristics of the observations: (i) the variation of the mode frequency with toroidal mode number, (ii) the chirping of the mode frequency for a given toroidal mode number, and (iii) the anti-ballooning density perturbation of the modes. It is now shown that these characteristics can be explained by observing that cylindrical-like modes can exist in the weak magnetic shear region of the plasma that then make a transition to TAEs as the central safety factor decreases in time.

  2. Beta-endorphin and alpha-n-acetyl beta-endorphin; synthesis, conformation and binding parameter

    SciTech Connect (OSTI)

    Lovegren, E.S.

    1986-01-01

    Beta-endorphin (EP) is a 31-residue opioid peptide found in many tissues, including the pituitary, brain and reproductive tract. Alpha-amino-acetyl beta-endorphin (AcEP) was characterized spectroscopically by proton nuclear magnetic resonance (NMR) and circular dichroism in deuterated water and trifluoroethanol (TFE). Both EP and AcEP bind to neuroblastoma N2a cells. This binding was not mediated through opiate receptors, and both peptides seemed to bind at common sites. Ovarian immunoreactive-EP levels were determined for immature and mature rates. These levels were found to be responsive to exogenous gonadotropin treatment in immature animals. A large percentage of the immunoreactive-EP is present in follicular fluid, and most of the endorphin-like peptides were acetylated, as measured by radioimmunoassay. Chromatogaphic analysis suggested at least three EP-like species: EP, a carboxy-terminally cleaved and an amino-terminally acetylated EP.

  3. Evaluation of probes used to detect alpha radiation 

    E-Print Network [OSTI]

    Sackett, Gregory Duane

    1995-01-01

    difficult to detect with survey meters. In response to these concerns several probes have been designed with an increased sensitivity to alpha radiation, combining larger sensitive surface areas with very thin windows to increase detector efficiency. Two...

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

    E-Print Network [OSTI]

    Schubert, Christian Reinhold

    2009-01-01

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

  5. Standoff alpha radiation detection via excited state absorption of air

    E-Print Network [OSTI]

    Yao, Jimmy; Brenizer, Jack; Hui, Rongqing; Yin, Stuart (Shizhuo)

    2013-06-24

    A standoff alpha radiation detection technique based on the physical mechanism of excited state absorption of air molecules was explored and is presented in this paper. Instead of directly detecting the radiation via measuring the intensity...

  6. Asteroseismology and calibration of alpha Cen binary system

    E-Print Network [OSTI]

    Thévenin, F; Morel, P; Berthomieu, G; Bouchy, F; Carrier, F

    2002-01-01

    Using the oscillation frequencies of alpha Cen A recently discovered by Bouchy & Carrier, the available astrometric, photometric and spectroscopic data, we tried to improve the calibration of the visual binary system alpha Cen. With the revisited masses of Pourbaix et al. (2002) we do not succeed to obtain a solution satisfying all the seismic observational constraints. Relaxing the constraints on the masses, we have found an age t_alpha Cen=4850+-500 Myr, an initial helium mass fraction Y_i = 0.300+-0.008, and an initial metallicity (Z/X)_i=0.0459+-0.0019, with M_A=1.100+-0.006M_o and M_B=0.907+-0.006M_o for alpha Cen A&B.

  7. Asteroseismology and calibration of alpha Cen binary system

    E-Print Network [OSTI]

    F. Thevenin; J. Provost; P. Morel; G. Berthomieu; F. Bouchy; F. Carrier

    2002-06-17

    Using the oscillation frequencies of alpha Cen A recently discovered by Bouchy & Carrier, the available astrometric, photometric and spectroscopic data, we tried to improve the calibration of the visual binary system alpha Cen. With the revisited masses of Pourbaix et al. (2002) we do not succeed to obtain a solution satisfying all the seismic observational constraints. Relaxing the constraints on the masses, we have found an age t_alpha Cen=4850+-500 Myr, an initial helium mass fraction Y_i = 0.300+-0.008, and an initial metallicity (Z/X)_i=0.0459+-0.0019, with M_A=1.100+-0.006M_o and M_B=0.907+-0.006M_o for alpha Cen A&B.

  8. {alpha}-cluster states in N{ne}Z nuclei

    SciTech Connect (OSTI)

    Goldberg, V. Z.; Rogachev, G. V.

    2012-10-20

    The importance of studies of {alpha}-Cluster structure in N{ne}Z light nuclei is discussed. Spin-parity assignments for the low-lying levels in {sup 10}C are suggested.

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

    E-Print Network [OSTI]

    Weston, Ken

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

  10. EXPERIMENT DEFINITION AND INTERGRATION STUDY FOR THE ACCOMMODATION OF MAGNETIC SPECTROMETER PAYLOAD ON SPACELAB/SHUTTLE MISSIONS

    E-Print Network [OSTI]

    Buffington, Dr. Andrew

    2011-01-01

    over the shields, and terminates at the tank pressure regulatank will normally vent through an absolute pressure regulator attached at the warm end of the vapor cooled shield

  11. Response function of the magnetic spectrometer PRISMA for the multinucleon transfer reaction {sup 40}Ar+{sup 208}Pb

    SciTech Connect (OSTI)

    Mijatovic, T.; Szilner, S.; Corradi, L.; Courtin, S.; Farnea, E.; Fioretto, E.; Gadea, A.; Goasduff, A.; Haas, F.; Jelavic-Malenica, D.; Lunardi, S.; Mengoni, D.; Montagnoli, G.; Montanari, D.; Pollarolo, G.; Recchia, F.; Sahin, E.; Scarlassara, F.; Soic, N.; Stefanini, A. M.; and others

    2012-10-20

    Multinucleon transfer reaction {sup 40}Ar+{sup 208}Pb has been investigated with the PRISMA-CLARA experimental setup in LNL, INFN, Italy. The experimental differential cross sections have been obtained for different transfer channels by measuring more than {Delta}{theta}{sub lab} = 20 Degree-Sign covered by three angular settings of PRISMA. Results have been compared with the semiclassical calculation GRAZING. Since the understanding of the reaction mechanism depends strongly on the determination of absolute cross section, effect of transport of ions through PRISMA has been studied via a Monte Carlo simulation code.

  12. Study of thermal neutron capture gamma rays using a lithium-drifted germanium spectrometer / [by] Victor John Orphan [and] Norman C. Rasmussen

    E-Print Network [OSTI]

    Orphan, V. J.

    1967-01-01

    A gamma-ray spectrometer, using a 30 cc coaxial Ge(Li) detector, which can be operated as a pair spectrometer at high energies and in the Compton suppression mode at low energies provides an effective means of obtaining ...

  13. Mapping the Cosmic Web with Ly-alpha Emission

    E-Print Network [OSTI]

    Steven Furlanetto; Joop Schaye; Volker Springel; Lars Hernquist

    2003-10-31

    We use a high-resolution cosmological simulation to predict the distribution of HI Ly-alpha emission from the low-redshift (z10^2 kpc) ``coronae'' of optically thin gas with Ly-alpha surface brightness close to the expected background. Most of these regions contain smaller cores of dense, cool gas. Unless self-shielded gas is able to cool to Tweb.

  14. Quantum Monte Carlo calculations of neutron-alpha scattering

    E-Print Network [OSTI]

    Kenneth M. Nollett; Steven C. Pieper; R. B. Wiringa; J. Carlson; G. M. Hale

    2006-12-09

    We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We find that a good three-nucleon interaction is crucial to obtain an accurate description of neutron-alpha scattering.

  15. Labeled ALPHA4BETA2 ligands and methods therefor

    DOE Patents [OSTI]

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

    2013-02-19

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

  16. Nuclear magnetic resonance experiments with dc SQUID amplifiers

    SciTech Connect (OSTI)

    Heaney, M.B. . Dept. of Physics Lawrence Berkeley Lab., CA )

    1990-11-01

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

  17. Preparation and synthetic application of {alpha}-phenylthioethylsamarium compound

    SciTech Connect (OSTI)

    Kasuga, Y.; Matsubara, S.; Utimoto, K. [Kyoto Univ. (Japan)

    1995-12-31

    Although samarium(II) iodide-mediated reaction of organohalides with carbonyl compounds has been applied to various organic syntheses, intermediary organosamarium species could be detected only when HMPA exists in the reaction system. The authors now report the detection of {alpha}-phenylthioethylsamarium compound in the absence of HMPA and application to diastereoselective reaction with aldehydes. A treatment of the organosamarium reagent, prepared from 1-chloroethyl phenyl sulfide and samarium(II) iodide, with D{sub 2}O afforded 1-deuterioethyl phenyl sulfide in 53% yield (82% D). The reagent reacted with aldehyde containing a stereogenic center at {alpha}-position to give {beta}-hydroxysulfide with high diastereoselectivity. Reaction using Barbier type procedure afforded the same results. These results suggest that {alpha}-phenylthioethylsamarium species is also generated in the Barbier type reaction. Configurational stability of {alpha}-thiosubstituted alkylmetal compounds seems to depend on the applied metal. Hoffmann Test indicated that the configuration of {alpha}-phenylthloethylsamarium compound is unchanged during the reaction with aldehyde, while that of {alpha}-alkylthioalkyllithium is unstable.

  18. Magnetic Damping For Maglev

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

    Zhu, S.; Cai, Y.; Rote, D.M.; Chen, S.S.

    1998-01-01

    Magnetic damping is one of the important parameters that control the response and stability of maglev systems. An experimental study to measure magnetic damping directly is presented. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters, such as conductivity, gap, excitation frequency, and oscillation amplitude, on magnetic damping. The experimental technique is capable of measuring all of the magnetic damping coefficients, some of which cannot be measured indirectly.

  19. Determination of alpha_S using hadronic event shape distributions of data taken with the OPAL detector

    E-Print Network [OSTI]

    Schieck, J

    2011-01-01

    The measurement of the strong coupling alpha_S using hadronic event shape distributions measured with the OPAL detector at center-of-mass energies between 91 and 209 GeV is summarized. For this measurement hadronic event shape distributions are compared to theoretical predictions based on next-to-next-to-leading-calculations (NNLO) and NNLO combined with resummed next-to-leading-logarithm calculations (NLLA). The combined result using NNLO calculations is alpha_S(MZ)=0.1201+-0.0008(stat.)+-0.0013(exp.)+-0.0010(had.)+-0.0024(theo.) and the result using NLLO and NLLA calculations is alpha_S(MZ)=0.1189+-0.0008(stat.)+-0.0016(exp.)=-0.0010(had.)+-0.0036(theo.), with both measurements being in agreement with the world average.

  20. Radiative-nonrecoil corrections of order {alpha}{sup 2}(Z{alpha}){sup 5} to the Lamb shift

    SciTech Connect (OSTI)

    Dowling, Matthew; Mondejar, Jorge; Piclum, Jan H.; Czarnecki, Andrzej [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2G7 (Canada)

    2010-02-15

    We present results for the corrections of order {alpha}{sup 2}(Z{alpha}){sup 5} to the Lamb shift. We compute all the contributing Feynman diagrams in dimensional regularization and a general covariant gauge using a mixture of analytical and numerical methods. We confirm results obtained by other groups and improve their precision. Values of the 32''master integrals'' for this and similar problems are provided.

  1. Numerical Code for LHCD Simulations with Self-consistent Treatment of Alpha Particles in Tokamak Geometry

    E-Print Network [OSTI]

    Numerical Code for LHCD Simulations with Self-consistent Treatment of Alpha Particles in Tokamak Geometry

  2. Modelling Neutral Particle Analyzer Measurements of High Energy Fusion Alpha-Particle Distributions in JET

    E-Print Network [OSTI]

    Modelling Neutral Particle Analyzer Measurements of High Energy Fusion Alpha-Particle Distributions in JET

  3. Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets

    SciTech Connect (OSTI)

    2010-10-01

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

  4. What do we do, if some of the MICE magnets can't be kept cold using the two-stage coolers?

    SciTech Connect (OSTI)

    Green, Michael A.

    2011-01-26

    Tests of the spectrometer solenoids have not been encouraging in terms of keeping the magnets cold using three 1.5 W (at 4.2 K) coolers. The spectrometer solenoids are being rebuilt with additional cooling capacity at 4.2 K. It is hoped that there will be sufficient 4.2 K cooling to keep the magnets cold. The spectrometer solenoids can be kept cold using liquid helium (up to a boil-off of 20 liters per day). This option does not apply for the other magnets in the MICE cooling channel, because there is not enough liquid helium storage within the magnet cold mass. It is important that the MICE collaboration ask the question, “How do we keep the MICE cooling channel magnets cold, if there isn’t sufficient cooling from the 4.2 K coolers?” This report discusses the cooling requirements at both 40 K and 4.2 K for all three types of MICE cooling channel magnets. This report discusses the steps that must be taken in the magnet fabrication to permit the magnets to be cooled using a small (20 to 40 W) external 4.2 K Claude cycle refrigerator. One must also ask the question as to whether there is enough excess capacity in the decay solenoid refrigerator to cool some of the MICE magnets. A plan for cooling the magnets using a Linde 1400 series refrigerator is presented. A plan for increasing the 4.4 K refrigeration from the existing decay solenoid refrigerator is also presented.

  5. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  6. Magnetic switch coupling to synchronize magnetic modulators

    DOE Patents [OSTI]

    Reed, Kim W. (Albuquerque, NM); Kiekel, Paul (Albuquerque, NM)

    1999-01-01

    Apparatus for synchronizing the output pulses from a pair of magnetic switches. An electrically conductive loop is provided between the pair of switches with the loop having windlings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself.

  7. Magnetic switch coupling to synchronize magnetic modulators

    DOE Patents [OSTI]

    Reed, K.W.; Kiekel, P.

    1999-04-27

    Apparatus for synchronizing the output pulses from a pair of magnetic switches is disclosed. An electrically conductive loop is provided between the pair of switches with the loop having windings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself. 13 figs.

  8. Controlling Magnetism at the Nanoscale

    E-Print Network [OSTI]

    Wong, Jared

    2012-01-01

    157 A.2 Magnetism Unit Conversion148 A.1 Magnetism Unit ConversionA·m) Table A.1: Magnetism Unit Conversion Table Quantity A.1

  9. Systematic effects in polarizing Fourier transform spectrometers for cosmic microwave background observations

    E-Print Network [OSTI]

    Nagler, Peter C; Kogut, Alan; Tucker, Gregory S

    2015-01-01

    The detection of the primordial B-mode polarization signal of the cosmic microwave background (CMB) would provide evidence for inflation. Yet as has become increasingly clear, the detection of a such a faint signal requires an instrument with both wide frequency coverage to reject foregrounds and excellent control over instrumental systematic effects. Using a polarizing Fourier transform spectrometer (FTS) for CMB observations meets both these requirements. In this work, we present an analysis of instrumental systematic effects in polarizing Fourier transform spectrometers, using the Primordial Inflation Explorer (PIXIE) as a worked example. We analytically solve for the most important systematic effects inherent to the FTS - emissive optical components, misaligned optical components, sampling and phase errors, and spin synchronous effects - and demonstrate that residual systematic error terms after corrections will all be at the sub-nK level, well below the predicted 100 nK B-mode signal.

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

    SciTech Connect (OSTI)

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

    2014-05-15

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

  11. The new Cold Neutron Chopper Spectrometer at the Spallation Neutron Source -- Design and Performance

    SciTech Connect (OSTI)

    Ehlers, Georg; Podlesnyak, Andrey A.; Niedziela, Jennifer L.; Iverson, Erik B.; Sokol, Paul E.

    2011-01-01

    The design and performance of the new cold neutron chopper spectrometer (CNCS) at the Spallation Neutron Source in Oak Ridge are described. CNCS is a direct-geometry inelastic time-of-flight spectrometer, designed essentially to cover the same energy and momentum transfer ranges as IN5 at ILL, LET at ISIS, DCS at NIST, TOFTOF at FRM-II, AMATERAS at J-PARC, PHAROS at LANSCE, and NEAT at HZB, at similar energy resolution. Measured values of key figures such as neutron flux at sample position and energy resolution are compared between measurements and ray tracing Monte Carlo simulations, and good agreement (better than 20% of absolute numbers) has been achieved. The instrument performs very well in the cold and thermal neutron energy ranges, and promises to become a workhorse for the neutron scattering community for quasielastic and inelastic scattering experiments.

  12. The new cold neutron chopper spectrometer at the Spallation Neutron Source: Design and performance

    SciTech Connect (OSTI)

    Ehlers, G.; Podlesnyak, A. A.; Niedziela, J. L.; Iverson, E. B.; Sokol, P. E.

    2011-08-15

    The design and performance of the new cold neutron chopper spectrometer (CNCS) at the Spallation Neutron Source in Oak Ridge are described. CNCS is a direct-geometry inelastic time-of-flight spectrometer, designed essentially to cover the same energy and momentum transfer ranges as IN5 at ILL, LET at ISIS, DCS at NIST, TOFTOF at FRM-II, AMATERAS at J-PARC, PHAROS at LANSCE, and NEAT at HZB, at similar energy resolution. Measured values of key figures such as neutron flux at sample position and energy resolution are compared between measurements and ray tracing Monte Carlo simulations, and good agreement (better than 20% of absolute numbers) has been achieved. The instrument performs very well in the cold and thermal neutron energy ranges, and promises to become a workhorse for the neutron scattering community for quasielastic and inelastic scattering experiments.

  13. Calculation of the Johann error for spherically bent x-ray imaging crystal spectrometers

    SciTech Connect (OSTI)

    Wang, E.; Beiersdorfer, P.; Gu, M.; Bitter, M.; Delgado-Aparicio, L.; Hill, K. W.; Reinke, M.; Rice, J. E.; Podpaly, Y.

    2010-10-15

    New x-ray imaging crystal spectrometers, currently operating on Alcator C-Mod, NSTX, EAST, and KSTAR, record spectral lines of highly charged ions, such as Ar{sup 16+}, from multiple sightlines to obtain profiles of ion temperature and of toroidal plasma rotation velocity from Doppler measurements. In the present work, we describe a new data analysis routine, which accounts for the specific geometry of the sightlines of a curved-crystal spectrometer and includes corrections for the Johann error to facilitate the tomographic inversion. Such corrections are important to distinguish velocity induced Doppler shifts from instrumental line shifts caused by the Johann error. The importance of this correction is demonstrated using data from Alcator C-Mod.

  14. X-Ray Imaging Crystal Spectrometer for Extended X-Ray Sources

    SciTech Connect (OSTI)

    Bitter, Manfred L.; Fraekel, Benjamin; Gorman, James L.; Hill, Kenneth W.; Roquemore, Lane A.; Stodiek, Wolfgang; Goeler, Schweickhard von

    1999-05-01

    Spherically or toroidally curved, double focusing crystals are used in a spectrometer for X-ray diagnostics of an extended X-ray source such as a hot plasma produced in a tokamak fusion experiment to provide spatially and temporally resolved data on plasma parameters such as ion temperature, toroidal and poloidal rotation, electron temperature, impurity ion charge-state distributions, and impurity transport. The imaging properties of these spherically or toroidally curved crystals provide both spectrally and spatially resolved X-ray data from the plasma using only one small spherically or toroidally curved crystal, thus eliminating the requirement for a large array of crystal spectrometers and the need to cross-calibrate the various crystals.

  15. A Compact, Backscattering Deplolarization Cloud Spectrometer for Ice and Water Discrimination

    SciTech Connect (OSTI)

    Thomson, David

    2014-05-15

    This project was to develop a compact optical particle spectrometer, small enough for operation on UAVS, that measures the optical diameter of cloud hydrometeors and differentiates their water phase (liquid or solid). To reach this goal, a work plan was laid out that would complete three objectives: 1) Evaluation of designs for an optical particle spectrometer that measures the component of light backscattered at two polarization angles. 2) Testing of selected designs on an optical bench. 3) Construction and preliminary testing of a prototype instrument based on the selected, optimum design. A protoype instrument was developed and tested in an icing wind tunnel where the results showed good measurement of cloud droplets and ice particles.

  16. Spectrometer for X-ray emission experiments at FERMI free-electron-laser

    SciTech Connect (OSTI)

    Poletto, L., E-mail: poletto@dei.unipd.it; Frassetto, F.; Miotti, P. [CNR - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, I-35131 Padova (Italy); Di Cicco, A.; Iesari, F. [Physics Division, School of Science and Technology, Universitŕ di Camerino, I-62032 Camerino (Italy); Finetti, P. [ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS) (Italy); Grazioli, C. [Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste (Italy); CNR-Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC, I-34149 Trieste (Italy); Kivimäki, A. [CNR-Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC, I-34149 Trieste (Italy); Stagira, S. [Politecnico di Milano – Department of Physics, I-20133 Milano (Italy); Coreno, M. [ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS) (Italy); CNR – Istituto di Struttura della Materia (CNR-ISM), UOS Basovizza, I-34149 Trieste (Italy)

    2014-10-15

    A portable and compact photon spectrometer to be used for photon in-photon out experiments, in particular x-ray emission spectroscopy, is presented. The instrument operates in the 25–800 eV energy range to cover the full emissions of the FEL1 and FEL2 stages of FERMI. The optical design consists of two interchangeable spherical varied-lined-spaced gratings and a CCD detector. Different input sections can be accommodated, with/without an entrance slit and with/without an additional relay mirror, that allow to mount the spectrometer in different end-stations and at variable distances from the target area both at synchrotron and at free-electron-laser beamlines. The characterization on the Gas Phase beamline at ELETTRA Synchrotron (Italy) is presented.

  17. Spectrometer for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR): Instrument Technology

    SciTech Connect (OSTI)

    Dunagan, Stephen; Johnson, Roy; Zavaleta, Jhony; Russell, P. B.; Schmid, Beat; Flynn, Connor J.; Redemann, Jens; Shinozuka, Yohei; Livingston, J.; Segal Rozenhaimer, Michal

    2013-08-06

    The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) combines airborne sun tracking and sky scanning with diffraction spectroscopy, to improve knowledge of atmospheric constituents and their links to air-pollution/climate. Direct beam hyper-spectral measurement of optical depth improves retrievals of gas constituents and determination of aerosol properties. Sky scanning enhances retrievals of aerosol type and size distribution. 4STAR measurements will tighten the closure between satellite and ground-based measurements. 4STAR incorporates a modular sun-tracking/ sky-scanning optical head with fiber optic signal transmission to rack mounted spectrometers, permitting miniaturization of the external optical head, and future detector evolution. Technical challenges include compact optical collector design, radiometric dynamic range and stability, and broad spectral coverage. Test results establishing the performance of the instrument against the full range of operational requirements are presented, along with calibration, engineering flight test, and scientific field campaign data and results.

  18. The response of CR-39 nuclear track detector to 19 MeV protons N. Sinenian, M. J. Rosenberg, M. Manuel, S. C. McDuffee, D. T. Casey et al.

    E-Print Network [OSTI]

    used in wedge-range-filter and magnetic charged-particle spectrometers,11 as well as neutron spec (2011) A high-sensitivity angle and energy dipersive multichannel electron momentum spectrometer with 2 also been studied using 5.5 MeV alpha particles over a 5-year period. Track diameters were found

  19. Portable gas chromatograph mass spectrometer for on-site chemical analyses

    DOE Patents [OSTI]

    Haas, Jeffrey S. (San Ramon, CA); Bushman, John F. (Oakley, CA); Howard, Douglas E. (Livermore, CA); Wong, James L. (Livermore, CA); Eckels, Joel D. (Livermore, CA)

    2002-01-01

    A portable, lightweight (approximately 25 kg) gas chromatograph mass spectrometer, including the entire vacuum system, can perform qualitative and quantitative analyses of all sample types in the field. The GC/MS has a conveniently configured layout of components for ease of serviceability and maintenance. The GC/MS system can be transported under operating or near-operating conditions (i.e., under vacuum and at elevated temperature) to reduce the downtime before samples can be analyzed on-site.

  20. Measurement of neutron spectrum in an AGN-201 reactor using a semiconductor neutron spectrometer 

    E-Print Network [OSTI]

    Stephenson, S. E

    1961-01-01

    . EXPERIMENTAL DETERMINATION OF NEUTRON SPECTRA. 12 Caiibration of the Spectrometer Measurement of Neutron Spectrum in an AGN-201 Reactor 14 III. DISCUSSION OF RESULTS IV. CONCLUSIONS . APPENDIX 24 29 32 Appendix I Appendix 2 Pulse Height Data... for Thermal Neutrons. . . Pulse Height Data for Energetic D(D, n)He 3 Neutrons 33 35 Appendix 3. Pulse Height Data for the AGN-201 Reactor Core Appendix 4. Data on Surface-Barrier Diode Lifetime Appendix 5. Surface-Barrier Diode Characteristics . 36...

  1. Elimination of ``memory`` from sample handling and inlet system of a mass spectrometer

    DOE Patents [OSTI]

    Chastgner, P.

    1991-05-08

    This paper describes a method for preparing the sample handling and inlet system of a mass spectrometer for analysis of a subsequent sample following analysis of a previous sample comprising the flushing of the system interior with supercritical CO{sub 2} and venting the interior. The method eliminates the effect of system ``memory`` on the subsequent analysis, especially following persistent samples such as xenon and krypton.

  2. STOCHASTIC HEATING, DIFFERENTIAL FLOW, AND THE ALPHA-TO-PROTON TEMPERATURE RATIO IN THE SOLAR WIND

    SciTech Connect (OSTI)

    Chandran, B. D. G.; Verscharen, D.; Isenberg, P. A.; Bourouaine, S.; Quataert, E.; Kasper, J. C. E-mail: s.bourouaine@unh.edu E-mail: daniel.verscharen@unh.edu E-mail: jkasper@cfa.harvard.edu

    2013-10-10

    We extend previous theories of stochastic ion heating to account for the motion of ions along the magnetic field B . We derive an analytic expression for the temperature ratio T{sub i}/T{sub p} in the solar wind assuming that stochastic heating is the dominant ion heating mechanism, where T{sub i} is the perpendicular temperature of species i and T{sub p} is the perpendicular proton temperature. This expression describes how T{sub i}/T{sub p} depends upon U{sub i} and ?{sub ?p}, where U{sub i} is the average velocity along B of species i in the proton frame and ?{sub ?p} is the ratio of the parallel proton pressure to the magnetic pressure, which we take to be ?< 1. We compare our model with previously published measurements of alpha particles and protons from the Wind spacecraft. We find that stochastic heating offers a promising explanation for the dependence of T{sub ?}/T{sub p} on U{sub ?} and ?{sub ?p} when the fractional cross helicity and Alfvén ratio at the proton-gyroradius scale have values that are broadly consistent with solar-wind measurements. We also predict how the temperatures of other ion species depend on their drift speeds.

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

    SciTech Connect (OSTI)

    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.

  4. Study of the performance of the MicroMegas chambers for the ATLAS Muon Spectrometer Upgrade

    E-Print Network [OSTI]

    Vanadia, Marco; The ATLAS collaboration

    2015-01-01

    Micromegas (MICRO MEsh GAseous Structure) chambers are Micro-Pattern Gaseous Detectors designed to provide a high spatial resolution in highly irradiated environments. In 2007 an ambitious long-term R&D activity was started in the context of the ATLAS experiment, at CERN: the Muon ATLAS Micromegas Activity (MAMMA). After years of tests on prototypes and technology breakthroughs, Micromegas chambers were chosen as tracking detectors for an upgrade of the ATLAS Muon Spectrometer. These novel detectors will be installed in 2018 and 2019 during the second long shutdown of the Large Hadron Collider, and will serve as precision detectors in the innermost part of the ATLAS Muon Spectrometer. Eight layers of Micromegas modules of unprecedented size, up to 3 $\\rm{{m^2}}$, will cover a surface of 150 $\\rm{{m^2}}$ for a total active area of about 1200 $\\rm{{m^2}}$. This upgrade will be crucial to ensure high quality performance for the ATLAS Muon Spectrometer in view of the third run of the Large Hadron Collider and...

  5. Measurement of a false electric dipole moment signal from $^{199}$Hg atoms exposed to an inhomogeneous magnetic field

    E-Print Network [OSTI]

    S. Afach; C. A. Baker; G. Ban; G. Bison; K. Bodek; Z. Chowdhuri; M. Daum; M. Fertl; B. Franke; P. Geltenbort; K. Green; M. G. D. van der Grinten; Z. Grujic; P. G. Harris; W. Heil; V. Hélaine; R. Henneck; M. Horras; P. Iaydjiev; S. N. Ivanov; M. Kasprzak; Y. Kermaďdic; K. Kirch; P. Knowles; H. -C. Koch; S. Komposch; A. Kozela; J. Krempel; B. Lauss; T. Lefort; Y. Lemičre; A. Mtchedlishvili; O. Naviliat-Cuncic; J. M. Pendlebury; F. M. Piegsa; G. Pignol; P. N. Prashant; G. Quéméner; D. Rebreyend; D. Ries; S. Roccia; P. Schmidt-Wellenburg; N. Severijns; A. Weis; E. Wursten; G. Wyszynski; J. Zejma; J. Zenner; G. Zsigmond

    2015-08-03

    We report on the measurement of a Larmor frequency shift proportional to the electric-field strength for $^{199}{\\rm Hg}$ atoms contained in a volume permeated with aligned magnetic and electric fields. This shift arises from the interplay between the inevitable magnetic field gradients and the motional magnetic field. The proportionality to electric-field strength makes it apparently similar to an electric dipole moment (EDM) signal, although unlike an EDM this effect is P- and T-conserving. We have used a neutron magnetic resonance EDM spectrometer, featuring a mercury co-magnetometer and an array of external cesium magnetometers, to measure the shift as a function of the applied magnetic field gradient. Our results are in good agreement with theoretical expectations.

  6. LOW-STATE MAGNETIC STRUCTURES IN POLARS: NATURE OR NURTURE?

    SciTech Connect (OSTI)

    Kafka, S.; Tappert, C.; Ribeiro, T.; Honeycutt, R. K.; Hoard, D. W.

    2010-10-01

    We present an orbit-resolved study of the magnetic cataclysmic variable (MCV) BL Hyi in its low state, and we explore the origin of its H{alpha} emission line components, their properties, and their possible formation mechanism. We tentatively associate one of the line components with a high-velocity component also seen in the high state. We propose a scenario in which streaming prominence-like magnetic loops (super-prominences) are kept in place by magnetic field interactions between the white dwarf and the donor star and are responsible for the high-velocity line components in the Balmer lines. We also discuss how this is in accord with the standard scenario of the secular evolution for MCVs. Finally, we offer an observational test of our ideas and present challenges for future theoretical studies.

  7. Magnetic Graphene Nanohole Superlattices

    E-Print Network [OSTI]

    Yu, Decai; Liu, Miao; Liu, Wei; Liu, Feng

    2008-01-01

    We investigate the magnetic properties of nano-holes (NHs) patterned in graphene using first principles calculations. We show that superlattices consisting of a periodic array of NHs form a new family of 2D crystalline "bulk" magnets whose collective magnetic behavior is governed by inter-NH spin-spin interaction. They exhibit long-range magnetic order well above room temperature. Furthermore, magnetic semiconductors can be made by doping magnetic NHs into semiconducting NH superlattices. Our findings offer a new material system for fundamental studies of spin-spin interaction and magnetic ordering in low dimensions, and open up the exciting opportunities of making engineered magnetic materials for storage media and spintronics applications.

  8. Magnetic assisted statistical assembly

    E-Print Network [OSTI]

    Cheng, Diana I

    2008-01-01

    The objective of this thesis is to develop a process using magnetic forces to assemble micro-components into recesses on silicon based integrated circuits. Patterned SmCo magnetic thin films at the bottom of recesses are ...

  9. Characterization of an aerodynamic lens for transmitting particles greater than 1 micrometer in diameter into the Aerodyne aerosol mass spectrometer

    E-Print Network [OSTI]

    Williams, L. R.

    We have designed and characterized a new inlet and aerodynamic lens for the Aerodyne aerosol mass spectrometer (AMS) that transmits particles between 80 nm and more than 3 ?m in vacuum aerodynamic diameter. The design of ...

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

    E-Print Network [OSTI]

    Verbeck, Guido Fridolin

    2005-08-29

    The construction of a liquid nitrogen-cooled ion mobility spectrometer coupled with time-of-flight mass spectrometry was implemented to demonstrate the ability to discriminate between electronic isomers. Ion mobility allows for the separation...

  11. Complexation of americium with {alpha}-d-iso-saccharinate

    SciTech Connect (OSTI)

    Allard, S.; Knutsson, A.; Oedegaard-Jensen, A.; Ekberg, C.; Jolsteraa, R.

    2008-07-01

    Under alkaline conditions, cellulose will degrade, with iso-saccharinate being the dominant end-product. One of the formed diastereomers, the {alpha}-D-iso-saccharinate, is a strong complexing agent for tri- and tetravalent actinides and is the dominant conformation at pH > 5, rendering other conformations insignificant at neutral to alkaline conditions. The presence of {alpha}-D-iso-saccharinate increases the amount of metal in solution and also affects the surface interactions. Understanding this complexation is of relevance for long-term repository assessments. This study has investigated the complexation of americium with {alpha}-D-iso-saccharinate using solvent-extraction and radioanalytical techniques at 25 deg. C. The stability constants for the complexation reactions were determined by curve fitting of a distribution-ratio equation to experimental data.

  12. Uncertainties on $\\alpha_S$ in the MMHT2014 global PDF analysis and implications for SM predictions

    E-Print Network [OSTI]

    Harland-Lang, L A; Motylinski, P; Thorne, R S

    2015-01-01

    We investigate the uncertainty in the value of the strong coupling $\\alpha_S(M_Z^2)$ when allowing it to be a free parameter in the recent MMHT global analyses of deep-inelastic and related hard scattering data that was undertaken to determine the parton distribution functions (PDFs) of the proton. The analysis uses the standard framework of leading twist fixed--order collinear factorisation in the ${\\overline {\\rm MS}}$ scheme. We study the constraints on the value of $\\alpha_S(M_Z^2)$ coming from the individual data sets by repeating the NNLO and NLO global analyses at various fixed values of $\\alpha_S(M_Z^2)$ about its optimum values, spanning the range $\\alpha_S(M_Z^2)=0.108$ to $0.128$ in units of $0.001$, and making all PDFs sets available. The inclusion of the measurements of the cross section for inclusive $t\\bar{t}$ production in the global fit allows us to explore the correlation between the values taken for the mass $m_t$ of the top quark and $\\alpha_S(M_Z^2)$. We find that the best fit values are ...

  13. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    DOE Patents [OSTI]

    Hilal, Sadek K. (Englewood Cliffs, NJ); Sampson, William B. (Bellport, NY); Leonard, Edward F. (Leonia, NJ)

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  14. Magnetic Fields Analogous to electric field, a magnet

    E-Print Network [OSTI]

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    Magnetic Fields Analogous to electric field, a magnet produces a magnetic field, B Set up a B field two ways: Moving electrically charged particles Current in a wire Intrinsic magnetic field Basic) Opposite magnetic poles attract like magnetic poles repel #12;Like the electric field lines

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

    E-Print Network [OSTI]

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

    2008-06-21

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

  16. Noble gas magnetic resonator

    DOE Patents [OSTI]

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  17. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14

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

  18. Metallic Magnetic Hetrostructures

    E-Print Network [OSTI]

    Leung, Chi Wah

    .2.2 Domains and magnetization processes 1.2.2.1 Domains and domain walls 1.2.2.2 Magnetization reversal and hysteresis 1.2.2.3 Modelling of magnetization process 1.3 Sputter deposition of thin films in this project 1.3.1 Substrate preparation 1.3.2 ‘UFO...

  19. Lyman alpha Transfer in a thick, dusty, and static medium

    E-Print Network [OSTI]

    Sang-Hyeon Ahn; Hee-Won Lee; Hyung-Mok Lee

    2000-06-13

    We developed a Monte Carlo code that describes the resonant Lyman alpha line transfer in an optically thick, dusty, and static medium. The code was tested against the analytic formula derived by Neufeld (1990). We explain the line transfer mechanism for a wide range of line center optical depths by tracing histories of photons in the medium. We find that photons escape from the medium by a series of wing scatterings, during which polarization may develop. We applied our code to examine the amount of dust extinction around the Lyman alpha in primeval galaxies. Brief discussions on the astrophysical application of our work are presented.

  20. Direct analysis of air filter samples for alpha emitting isotopes

    SciTech Connect (OSTI)

    Mohagheghi, A.H.; Ghanbari, F.; Ebara, S.B.; Enghauser, M.E. [Sandia National Labs., Albuquerque, NM (United States); Bakhtiar, S.N. [Westinghouse WIPP, Carlsbad, NM (United States)

    1997-04-01

    The traditional method for determination of alpha emitting isotopes on air filters has been to process the samples by radiochemical methods. However, this method is too slow for cases of incidents involving radioactive materials where the determination of personnel received dose is urgent. A method is developed to directly analyze the air filters taken from personal and area air monitors. The site knowledge is used in combination with alpha spectral information to identify isotopes. A mathematical function is developed to estimate the activity for each isotope. The strengths and weaknesses of the method are discussed.