WorldWideScience

Sample records for normal incidence spectrometer

  1. The Normal-incidence Vacuum-ultraviolet Spectrometer for the TJ-II and First Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, K.J.; Zurro, B.; Baciero, A.

    2002-07-01

    A normal-incidence spectrometer, operating in the extreme-ultraviolet and ultraviolet wavelength regions, has been commissioned for the TJ-II stellarator. The instrument has been custom built by McPherson, Chelmsford, MA, and has several unique features and accessories that are described here. The instrument and CCD detector has been tested and calibrated, and its performance evaluated, using spectral lines from glow discharges and a RF excited flow lamp. Finally, the first spectra collected with the instrument of TJ-II plasmas are presented and a preliminary estimation of an oxygen ion temperature is made. (Author) 23 refs.

  2. The Normal-incidence Vacuum-ultraviolet Spectrometer for the TJ-II and First Experimental Results

    International Nuclear Information System (INIS)

    McCarthy, K. J.; Zurro, B.; Baciero, A.

    2002-01-01

    A normal-incidence spectrometer, operating in the extreme-ultraviolet and ultraviolet wavelength regions, has been commissioned for the TJ-II stellarator. The instrument has been custom built by McPherson, Chelmsford, MA, and has several unique features and accessories that are described here. The instrument and CCD detector has been tested and calibrated, and its performance evaluated, using spectral lines from glow discharges and a RF excited flow lamp. Finally, the first spectra collected with the instrument of TJ-II plasmas are presented and a preliminary estimation of an oxygen ion temperature is made. (Author) 23 refs

  3. The quiet Sun extreme ultraviolet spectrum observed in normal incidence by the SOHO Coronal Diagnostic Spectrometer

    CERN Document Server

    Brooks, D H; Fludra, A; Harrison, R A; Innes, D E; Landi, E; Landini, M; Lang, J; Lanzafame, A C; Loch, S D; McWhirter, R W P; Summers, H P; Thompson, W T

    1999-01-01

    The extreme ultraviolet quiet Sun spectrum, observed at normal incidence by the Coronal Diagnostic Spectrometer on the SOHO spacecraft, is presented. The spectrum covers the wavelength ranges 308-381 AA and 513-633 AA and is based $9 on data recorded at various positions on the solar disk between October 1996 and February 1997. Datasets at twelve of these `positions' were judged to be free from active regions and data faults and selected for detailed study. A $9 constrained maximum likelihood spectral line fitting code was used to analyse the spectral features. In all over 200 spectrum lines have been measured and about 50 186584dentified. The line identification process consisted of a $9 number of steps. Firstly assignment of well known lines was made and used to obtain the primary wavelength calibration. Variations of wavelengths with position were used to assess the precision of calibration achievable. Then, an $9 analysis method first used in studies with the CHASE experiment, was applied to the new obser...

  4. The Marshall Grazing Incidence X-ray Spectrometer

    Science.gov (United States)

    Kobayashi, Ken; Winebarger, Amy R.; Savage, Sabrina; Champey, Patrick; Cheimets, Peter N.; Hertz, Edward; Bruccoleri, Alexander R.; Golub, Leon; Ramsey, Brian; Ranganathan, Jaganathan; Marquez, Vanessa; Allured, Ryan; Parker, Theodore; Heilmann, Ralf K.; Schattenburg, Mark L.

    2017-08-01

    The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a NASA sounding rocket instrument designed to obtain spatially resolved soft X-ray spectra of the solar atmosphere in the 6-24 Å (0.5-2.0 keV) range. The instrument consists of a single shell Wolter Type-I telescope, a slit, and a spectrometer comprising a matched pair of grazing incidence parabolic mirrors and a planar varied-line space diffraction grating. The instrument is designed to achieve a 50 mÅ spectral resolution and 5 arcsecond spatial resolution along a +/-4-arcminute long slit, and launch is planned for 2019. We report on the status and our approaches for fabrication and alignment for this novel optical system. The telescope and spectrometer mirrors are replicated nickel shells, and are currently being fabricated at the NASA Marshall Space Flight Center. The diffraction grating is currently under development by the Massachusetts Institute of Technology (MIT); because of the strong line spacing variation across the grating, it will be fabricated through e-beam lithography.

  5. A method of incident angle estimation for high resolution spectral recovery in filter-array-based spectrometers

    Science.gov (United States)

    Kim, Cheolsun; Lee, Woong-Bi; Ju, Gun Wu; Cho, Jeonghoon; Kim, Seongmin; Oh, Jinkyung; Lim, Dongsung; Lee, Yong Tak; Lee, Heung-No

    2017-02-01

    In recent years, there has been an increasing interest in miniature spectrometers for research and development. Especially, filter-array-based spectrometers have advantages of low cost and portability, and can be applied in various fields such as biology, chemistry and food industry. Miniaturization in optical filters causes degradation of spectral resolution due to limitations on spectral responses and the number of filters. Nowadays, many studies have been reported that the filter-array-based spectrometers have achieved resolution improvements by using digital signal processing (DSP) techniques. The performance of the DSP-based spectral recovery highly depends on the prior information of transmission functions (TFs) of the filters. The TFs vary with respect to an incident angle of light onto the filter-array. Conventionally, it is assumed that the incident angle of light on the filters is fixed and the TFs are known to the DSP. However, the incident angle is inconstant according to various environments and applications, and thus TFs also vary, which leads to performance degradation of spectral recovery. In this paper, we propose a method of incident angle estimation (IAE) for high resolution spectral recovery in the filter-array-based spectrometers. By exploiting sparse signal reconstruction of the L1- norm minimization, IAE estimates an incident angle among all possible incident angles which minimizes the error of the reconstructed signal. Based on IAE, DSP effectively provides a high resolution spectral recovery in the filter-array-based spectrometers.

  6. X-ray photographs of a solar active region with a multilayer telescope at normal incidence

    Science.gov (United States)

    Underwood, J. H.; Bruner, M. E.; Haisch, B. M.; Brown, W. A.; Acton, L. W.

    1987-01-01

    An astronomical photograph was obtained with a multilayer X-ray telescope. A 4-cm tungsten-carbon multilayer mirror was flown as part of an experimental solar rocket payload, and successful images were taken of the sun at normal incidence at a wavelength of 44 A. Coronal Si XII emission from an active region was recorded on film; as expected, the structure is very similar to that observed at O VIII wavelengths by the Solar Maximum Mission flat-crystal spectrometer at the same time. The small, simple optical system used in this experiment appears to have achieved a resolution of 5 to 10 arcsec.

  7. SPRED: a multichannel grazing-incidence spectrometer for plasma impurity diagnosis

    International Nuclear Information System (INIS)

    Fonck, R.J.; Ramsey, A.T.; Yelle, R.V.

    1982-03-01

    A compact vacuum ultraviolet spectrometer system has been developed to provide time-resolved impurity spectra from tokamak plasmas. Two interchangeable aberration-corrected toroidal diffraction gratings with flat focal fields provide simultaneous coverage over the ranges 100 to 1100 A or 160 to 1700 A. The detector is an intensified self-scanning photodiode array. Spectral resolution is 2 A with the higher dispersion grating. Minimum readout time for a full spectrum is 20 ms, but up to 7 individual spectral lines can be measured with a 1 ms time resolution. The sensitivity of the system is comparable to that of a conventional grazing incidence monochromator

  8. SPRED: a multichannel grazing-incidence spectrometer for plasma impurity diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Fonck, R.J.; Ramsey, A.T.; Yelle, R.V.

    1982-03-01

    A compact vacuum ultraviolet spectrometer system has been developed to provide time-resolved impurity spectra from tokamak plasmas. Two interchangeable aberration-corrected toroidal diffraction gratings with flat focal fields provide simultaneous coverage over the ranges 100 to 1100 A or 160 to 1700 A. The detector is an intensified self-scanning photodiode array. Spectral resolution is 2 A with the higher dispersion grating. Minimum readout time for a full spectrum is 20 ms, but up to 7 individual spectral lines can be measured with a 1 ms time resolution. The sensitivity of the system is comparable to that of a conventional grazing incidence monochromator.

  9. Sensitivity determination of CR-39 from Normal and inclined incidence

    International Nuclear Information System (INIS)

    Abou, A.A.; El-Kheir, A.A.; Daas, A.F.; Awwad, Z.; Reda, A.M.

    2000-01-01

    An experimental study have been carried out on alpha- particle track opening (Major and minor axes) using alpha-particles of different energies incident with different angels in addition to the normal incidence. The sensitivity of CR-39 in present work is determined for each of normal and inclined incidence. The results indicated a difference in the sensitivity according to angle of incidence. The variation of alpha- particle tracks (major and minor axes) are calculated and compared with our measured values. Also, it is found that the sensitivity of CR-39 detector is change due to the storage time at room temperature

  10. Design of a normal incidence multilayer imaging X-ray microscope

    Science.gov (United States)

    Shealy, David L.; Gabardi, David R.; Hoover, Richard B.; Walker, Arthur B. C., Jr.; Lindblom, Joakim F.

    Normal incidence multilayer Cassegrain X-ray telescopes were flown on the Stanford/MSFC Rocket X-ray Spectroheliograph. These instruments produced high spatial resolution images of the sun and conclusively demonstrated that doubly reflecting multilayer X-ray optical systems are feasible. The images indicated that aplanatic imaging soft X-ray/EUV microscopes should be achievable using multilayer optics technology. A doubly reflecting normal incidence multilayer imaging X-ray microscope based on the Schwarzschild configuration has been designed. The design of the microscope and the results of the optical system ray trace analysis are discussed. High resolution aplanatic imaging X-ray microscopes using normal incidence multilayer X-ray mirrors should have many important applications in advanced X-ray astronomical instrumentation, X-ray lithography, biological, biomedical, metallurgical, and laser fusion research.

  11. Normal incidence spectrophotometer using high density transmission grating technology and highly efficiency silicon photodiodes for absolute solar EUV irradiance measurements

    Science.gov (United States)

    Ogawa, H. S.; Mcmullin, D.; Judge, D. L.; Korde, R.

    1992-01-01

    New developments in transmission grating and photodiode technology now make it possible to realize spectrometers in the extreme ultraviolet (EUV) spectral region (wavelengths less than 1000 A) which are expected to be virtually constant in their diffraction and detector properties. Time dependent effects associated with reflection gratings are eliminated through the use of free standing transmission gratings. These gratings together with recently developed and highly stable EUV photodiodes have been utilized to construct a highly stable normal incidence spectrophotometer to monitor the variability and absolute intensity of the solar 304 A line. Owing to its low weight and compactness, such a spectrometer will be a valuable tool for providing absolute solar irradiance throughout the EUV. This novel instrument will also be useful for cross-calibrating other EUV flight instruments and will be flown on a series of Hitchhiker Shuttle Flights and on SOHO. A preliminary version of this instrument has been fabricated and characterized, and the results are described.

  12. Normal-incidence spectroscopic ellipsometry for critical dimension monitoring

    International Nuclear Information System (INIS)

    Huang, Hsu-Ting; Kong, Wei; Terry, Fred Lewis

    2001-01-01

    In this letter, we show that normal-incidence spectroscopic ellipsometry can be used for high-accuracy topography measurements on surface relief gratings. We present both experimental and theoretical results which show that spectroscopic ellipsometry or reflectance-difference spectroscopy at near-normal incidence coupled with vector diffraction theory for data analysis is capable of high-accuracy critical dimension (CD), feature height, and sidewall angle measurements in the extreme submicron regime. Quantitative comparisons of optical and cross-sectional scanning electron microscopy (SEM) topography measurements from a number of 350 nm line/space reactive-ion-etched Si gratings demonstrate the strong potential for in situ etching monitoring. This technique can be used for both ex situ and in situ applications and has the potential to replace the use of CD-SEM measurements in some applications. [copyright] 2001 American Institute of Physics

  13. Development of an imaging VUV monochromator in normal incidence region

    Energy Technology Data Exchange (ETDEWEB)

    Koog, Joong-San

    1996-07-01

    This paper describes a development of the two-dimensional imaging monochromator system. A commercial normal incidence monochromator working on off-Rowland circle mounting is used for this purpose. The imaging is achieved with utilizing the pinhole camera effect created by an entrance slit of limited height. The astigmatism in the normal incidence mounting is small compared with a grazing incidence mount, but has a finite value. The point is that for near normal incidence, the vertical focusing with a concave grating is produced at outside across the exit slit. Therefore, by putting a 2-D detector at the position away from the exit slit ({approx}30 cm), a one-to-one correspondence between the position of a point on the detector and where it originated in the source is accomplished. This paper consists of (1) the principle and development of the imaging monochromator using the off-Rowland mounting, including the 2-D detector system, (2) a computer simulation by ray tracing for investigations of the imaging properties of imaging system, and aberration from the spherical concave grating on the exit slit, (3) the plasma light source (TPD-S) for the test experiments, (4) Performances of the imaging monochromator system on the spatial resolution and sensitivity, and (5) the use of this system for diagnostic studies on the JIPP T-IIU tokamak. (J.P.N.)

  14. Development of an imaging VUV monochromator in normal incidence region

    International Nuclear Information System (INIS)

    Koog, Joong-San.

    1996-07-01

    This paper describes a development of the two-dimensional imaging monochromator system. A commercial normal incidence monochromator working on off-Rowland circle mounting is used for this purpose. The imaging is achieved with utilizing the pinhole camera effect created by an entrance slit of limited height. The astigmatism in the normal incidence mounting is small compared with a grazing incidence mount, but has a finite value. The point is that for near normal incidence, the vertical focusing with a concave grating is produced at outside across the exit slit. Therefore, by putting a 2-D detector at the position away from the exit slit (∼30 cm), a one-to-one correspondence between the position of a point on the detector and where it originated in the source is accomplished. This paper consists of 1) the principle and development of the imaging monochromator using the off-Rowland mounting, including the 2-D detector system, 2) a computer simulation by ray tracing for investigations of the imaging properties of imaging system, and aberration from the spherical concave grating on the exit slit, 3) the plasma light source (TPD-S) for the test experiments, 4) Performances of the imaging monochromator system on the spatial resolution and sensitivity, and 5) the use of this system for diagnostic studies on the JIPP T-IIU tokamak. (J.P.N.)

  15. Normal Incidence for Graded Index Surfaces

    Science.gov (United States)

    Khankhoje, Uday K.; Van Zyl, Jakob

    2011-01-01

    A plane wave is incident normally from vacuum (eta(sub 0) = 1) onto a smooth surface. The substrate has three layers; the top most layer has thickness d(sub 1) and permittivity epsilon(sub 1). The corresponding numbers for the next layer are d(sub 2); epsilon(sub 2), while the third layer which is semi-in nite has index eta(sub 3). The Hallikainen model [1] is used to relate volumetric soil moisture to the permittivity. Here, we consider the relation for the real part of the permittivity for a typical loam soil: acute epsilon(mv) = 2.8571 + 3.9678 x mv + 118:85 x mv(sup 2).

  16. Status of Mirror Development for the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS)

    Science.gov (United States)

    Champey, P. R.; Winebarger, A. R.; Kobayashi, K.; Savage, S. L.; Ramsey, B.; Kolodziejczak, J.; Speegle, C.; Young, M.; Kester, T.; Cheimets, P.; Hertz, E.

    2017-12-01

    The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a NASA sounding rocket instrument designed to observe soft X-ray emissions at 0.5 - 2.0 keV energies (24 - 6 Å) from a solar active region. MaGIXS will, for the first time, obtain spatially resolved spectra of high-temperature, low-emission plasma within an active region core. The unique optical design includes a Wolter I telescope and a 3-optic grazing incidence spectrograph. The spectrograph consists of a finite conjugate, stigmatic mirror pair and a planar varied line space grating. The grazing incidence mirrors are being developed at NASA Marshall Space Flight Center (MSFC) and are produced using electroform nickel-replication techniques, employing the same facilities developed for HERO, FOXSI, ART-XC and IXPE. The MaGIXS mirror mandrels have been fabricated, figured, and have completed the first phase of polishing. A set of three test shells were replicated and exposed to X-rays in the Stray Light Facility (SLF) at MSFC. Here we present results from mandrel metrology and X-ray testing at the SLF. We also discuss the development of a new polishing technique for the MaGIXS mirror mandrels, where we plan to use the Zeeko polishing machine.

  17. [Idiopathic normal pressure hydrocephalus: High incidence in people over 80 years of age].

    Science.gov (United States)

    Aragonès, Josep Maria; Altimiras, Jacint; Alonso, Francisco; Roura, Pere; Alfonso, Sebastián; Bajo, Lorena

    Idiopathic normal pressure hydrocephalus is usually observed in adults over 60 years of age. The highest incidence of cases is between 70 and 80 years-old, and it could be under-diagnosed in over 80 year-olds. A description is presented on the overall incidence and age group incidence, the delay in the diagnosis, and main outcomes. A descriptive study was performed on patients with idiopathic normal pressure hydrocephalus, in the population of Osona County during the years 2010-2015. The annual incidence rate was 4.43 per 100,000 inhabitants. The incidence increased with age; from 8.09 per 100,000 in the 60 to 69 years age group, to 23.61 per 100,000 in the 70-79 years age group of, and to 37.02 per 100,000 in the 80-89 years age. The delay in the diagnosis was 15.01 ± 10.35 months. All the patients improved after surgery, but only 73.3% of the patients maintained the improvement after one year. Idiopathic normal pressure hydrocephalus is an age related disease and probably underdiagnosed in the elderly. An early diagnosis and a clinical suspicion are essential in patients over 80 years old. Copyright © 2017 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Higher levels of albuminuria within the normal range predict incident hypertension.

    Science.gov (United States)

    Forman, John P; Fisher, Naomi D L; Schopick, Emily L; Curhan, Gary C

    2008-10-01

    Higher levels of albumin excretion within the normal range are associated with cardiovascular disease in high-risk individuals. Whether incremental increases in urinary albumin excretion, even within the normal range, are associated with the development of hypertension in low-risk individuals is unknown. This study included 1065 postmenopausal women from the first Nurses' Health Study and 1114 premenopausal women from the second Nurses' Health Study who had an albumin/creatinine ratio who did not have diabetes or hypertension. Among the older women, 271 incident cases of hypertension occurred during 4 yr of follow-up, and among the younger women, 296 incident cases of hypertension occurred during 8 yr of follow-up. Cox proportional hazards regression was used to examine prospectively the association between the albumin/creatinine ratio and incident hypertension after adjustment for age, body mass index, estimated GFR, baseline BP, physical activity, smoking, and family history of hypertension. Participants who had an albumin/creatinine ratio in the highest quartile (4.34 to 24.17 mg/g for older women and 3.68 to 23.84 mg/g for younger women) were more likely to develop hypertension than those who had an albumin/creatinine ratio in the lowest quartile (hazard ratio 1.76 [95% confidence interval 1.21 to 2.56] and hazard ratio 1.35 [95% confidence interval 0.97 to 1.91] for older and younger women, respectively). Higher albumin/creatinine ratios, even within the normal range, are independently associated with increased risk for development of hypertension among women without diabetes. The definition of normal albumin excretion should be reevaluated.

  19. Development of a cosmic veto gamma-spectrometer

    International Nuclear Information System (INIS)

    Burnett, J.L.; Davies, A.V.

    2012-01-01

    Cosmic radiation contributes significantly towards the background radiation measured by a gamma-spectrometer. A novel cosmic veto gamma-spectrometer has been developed that provides a mean background reduction of 54.5%. The system consists of plastic scintillation plates operated in time-stamp mode to detect coincident muon interactions within an HPGe gamma-spectrometer. The instrument is easily configurable and provides improved sensitivity for radionuclides indicative of nuclear weapons tests and reactor incidents, including 140 Ba, 95 Zr, 99 Mo, 141 Ce, 147 Nd, 131 I, 134 Cs and 137 Cs. This has been demonstrated for Comprehensive Nuclear-Test-Ban Treaty applications to obtain the required 140 Ba MDA of 24 mBq within 2 days counting. Analysis of an air filter sample collected during the Fukushima incident indicates improved sensitivity compared to conventional gamma-spectrometers. (author)

  20. Orbital Normalization of MESSENGER Gamma-Ray Spectrometer Data

    Science.gov (United States)

    Rhodes, E. A.; Peplowski, P. N.; Evans, L. G.; Hamara, D. K.; Boynton, W. V.; Solomon, S. C.

    2011-12-01

    The MESSENGER Gamma-Ray Spectrometer (GRS) measures energy spectra of gamma rays emanating from the surface of Mercury. Analysis of these spectra provides elemental abundances of surface material. The MESSENGER mission necessarily provides some data normalization challenges for GRS analysis. So as to keep the spacecraft cool while orbiting the dayside of the planet, the orbits are highly eccentric, with altitudes varying from 200-500 km to ~ 15,000 km. A small fraction of time is spent at the low altitudes where gamma-ray signals are largest, requiring a large number of orbits to yield sufficient counting statistics for elemental analysis. Also, the sunshade must always shield the spacecraft from the Sun, which causes the orientation of the GRS often to be far from nadir-pointing, so the detector efficiency and attenuation of gamma rays from the planet must be known for a wide range of off-nadir orientations. An efficiency/attenuation map for the expected ranges of orientations and energies was constructed in a ground calibration experiment for a limited range of orientations using a nuclear reactor and radioisotope sources, and those results were extended to other orientations by radiation transport computations using as input a computer-aided design model of the spacecraft and its composition. This normalization has allowed abundance determinations of elements K, Th, and U from radioisotopes of these elements in the Mercury regolith during the first quarter of the year-long mission. These results provide constraints on models of Mercury's chemical and thermal evolution. The normalization of gamma-ray spectra for surface elements not having radioisotopes is considerably more complex; these gamma rays come from neutron inelastic-scatter and capture reactions in the regolith, where the neutrons are generated by cosmic ray impact onto the planet. A radiation transport computation was performed to generate the expected count rates in the neutron-generated gamma

  1. High-resolution VUV spectra of carbon, neon and argon in a wavelength range of 250 to 2300 A for plasma diagnostics observed with a 3 m normal incidence spectrometer in LHD

    International Nuclear Information System (INIS)

    Katai, Ryuji; Morita, Shigeru; Goto, Motoshi

    2007-01-01

    Intrinsic impurities have been much reduced in toroidal fusion devices through the development of several wall-conditioning techniques as well as by the use of carbon materials in the first wall and divertor plates. Impurity elements useful for passive plasma spectroscopy have been then extremely limited. At present, only carbon is a subject for spectroscopic diagnostics in most discharges except for fuel atoms. The use of rare gas as a brighter light source is a method to overcome the present difficulty in passive spectroscopy. Recently, rare gases have also been used for edge cooling to reduce the divertor heat flux. Therefore, high-resolution spectra (Δλ - 0.2 A) from neon and argon in a 250 to 2300 A wavelength range have been measured using a 3 m normal incidence spectrometer in Large Helical Device (LHD) and the measured spectra were precisely analyzed. The VUV spectra of carbon, neon and argon are presented for spectroscopic use and their wavelengths are tabulated with their relative intensities. The spectral profiles of almost all the spectral lines measured here are formed by the Doppler broadening and self-absorption processes. The Doppler broadening of neon and argon spectra are plotted against the ionization energies and Doppler spectra from carbon lines are presented. The self-absorption spectra of the hydrogen Lyman-α line, which are found in the LHD high-density discharge, are also presented and the neutral density is analytically estimated. (author)

  2. Calculational approach to ionization spectrometer design

    International Nuclear Information System (INIS)

    Gabriel, T.A.

    1974-01-01

    Many factors contribute to the design and overall performance of an ionization spectrometer. These factors include the conditions under which the spectrometer is to be used, the required performance, the development of the hadronic and electromagnetic cascades, leakage and binding energies, saturation effects of densely ionizing particles, nonuniform light collection, sampling fluctuations, etc. The calculational procedures developed at Oak Ridge National Laboratory that have been applied to many spectrometer designs and that include many of the influencing factors in spectrometer design are discussed. The incident-particle types which can be considered with some generality are protons, neutrons, pions, muons, electrons, positrons, and gamma rays. Charged kaons can also be considered but with less generality. The incident-particle energy range can extend into the hundreds of GeV range. The calculations have been verified by comparison with experimental data but only up to approximately 30 GeV. Some comparisons with experimental data are also discussed and presented so that the flexibility of the calculational methods can be demonstrated. (U.S.)

  3. Characterisation of the incident beam and current diffraction capabilities on the VESUVIO spectrometer

    Science.gov (United States)

    Romanelli, G.; Krzystyniak, M.; Senesi, R.; Raspino, D.; Boxall, J.; Pooley, D.; Moorby, S.; Schooneveld, E.; Rhodes, N. J.; Andreani, C.; Fernandez-Alonso, F.

    2017-09-01

    The VESUVIO spectrometer at the ISIS pulsed neutron and muon source is a unique instrument amongst those available at neutron facilities. This is the only inverted-geometry neutron spectrometer accessing values of energy and wavevector transfer above tens of eV and {\\mathringA}-1 , respectively, and where deep inelastic neutron scattering experiments are routinely performed. As such, the procedure at the base of the technique has been previously described in an article published by this journal (Mayers and Reiter 2012 Meas. Sci. Technol. 23 045902). The instrument has recently witnessed an upsurge of interest due to a new trend to accommodate, within a single experiment, neutron diffraction and transmission measurements in addition to deep inelastic neutron scattering. This work presents a broader description of the instrument following these recent developments. In particular, we assess the absolute intensity and two-dimensional profile of the incident neutron beam and the capabilities of the backscattering diffraction banks. All results are discussed in the light of recent changes to the moderator viewed by the instrument. We find that VESUVIO has to be considered a high-resolution diffractometer as much as other diffractometers at ISIS, with a resolution as high as 2× 10-3 in backscattering. Also, we describe the extension of the wavelength range of the instrument to include lower neutron energies for diffraction measurements, an upgrade that could be readily applied to other neutron instruments as well.

  4. HISS spectrometer

    International Nuclear Information System (INIS)

    Greiner, D.E.

    1984-11-01

    This talk describes the Heavy Ion Spectrometer System (HISS) facility at the Lawrence Berkeley Laboratory's Bevalac. Three completed experiments and their results are illustrated. The second half of the talk is a detailed discussion of the response of drift chambers to heavy ions. The limitations of trajectory measurement over a large range in incident particle charge are presented

  5. Speckle-based spectrometer

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Jakobsen, Michael Linde; Hanson, Steen Grüner

    2015-01-01

    A novel spectrometer concept is analyzed and experimentally verified. The method relies on probing the speckle displacement due to a change in the incident wavelength. A rough surface is illuminated at an oblique angle, and the peak position of the covariance between the speckle patterns observed...

  6. Microwave Absorption Properties of Co@C Nanofiber Composite for Normal and Oblique Incidence

    Science.gov (United States)

    Zhang, Junming; Wang, Peng; Chen, Yuanwei; Wang, Guowu; Wang, Dian; Qiao, Liang; Wang, Tao; Li, Fashen

    2018-05-01

    Co@C nanofibers have been prepared by an electrospinning technique. Uniform morphology of the nanofibers and good dispersion of the magnetic cobalt nanoparticles in the carbon fiber frame were confirmed by field-emission scanning electron microscopy and high-resolution transmission electron microscopy. The electromagnetic parameters of a composite absorber composed of Co@C nanofibers/paraffin were measured from 2 GHz to 15 GHz. The electromagnetic wave absorption properties were simulated and investigated in the case of normal and oblique incidence. In the normal case, the absorber achieved absorption performance of - 40 dB at 7.1 GHz. When the angle of incidence was increased to 60°, the absorption effect with reflection loss (RL) exceeding - 10 dB could still be obtained. These results demonstrate that the reported Co@C nanofiber absorber exhibits excellent absorption performance over a wide range of angle of incidence.

  7. Detailed characterisation of the incident neutron beam on the TOSCA spectrometer

    Science.gov (United States)

    Pinna, Roberto S.; Rudić, Svemir; Capstick, Matthew J.; McPhail, David J.; Pooley, Daniel E.; Howells, Gareth D.; Gorini, Giuseppe; Fernandez-Alonso, Felix

    2017-10-01

    We report a detailed characterisation of the incident neutron beam on the TOSCA spectrometer. A bespoke time-of-flight neutron monitor has been designed, constructed and used to perform extensive spatially resolved measurements of the absolute neutron flux and its underlying time structure at the instrument sample position. The obtained data give a quantitative understanding of the current instrument beyond neutronic simulations and provide a baseline in order to assess the performance of the upgraded instrument. At an average proton current-on-target of 153 μA (ISIS Target Station 1; at the time of measurements) we have found that the wavelength-integrated neutron flux (from 0.28 Å to 4.65 Å) at the position of the TOSCA instrument sample (spatially averaged across the 3 × 3cm2 surface centred around (0,0) position) is approximately 1 . 2 × 106 neutrons cm-2s-1, while the whole beam has a homogeneous distribution across the 3 . 0 × 3 . 5cm2 sample surface. The spectra reproduced the well-known shape of the neutrons moderated by the room temperature water moderator and exhibit a neutron flux of 7 . 3 × 105 neutrons cm-2s-1Å-1 at 1 Å.

  8. Impact of increasing alanine aminotransferase levels within normal range on incident diabetes

    OpenAIRE

    Chong-Shan Wang; Ting-Tsung Chang; Wei-Jen Yao; Shan-Tair Wang; Pesus Chou

    2012-01-01

    Abnormal alanine aminotransferase level (ALT) levels might be associated with type 2 diabetes, but whether higher ALT levels within the normal range predict the risk is unknown. Methods: We followed a community-based cohort of 3446 individuals who were ≥35 years old without diabetes and hepatitis B or C in southern Taiwan for 8 years (1997–2004) to study the risk for type 2 diabetes with different normal ALT levels. Results: Among the 337 incident diabetes cases, 16.0% were from those w...

  9. 3m vacuum ultraviolet spectrometer with optical multichanel detector

    International Nuclear Information System (INIS)

    Marin, P.; Peraza, C.; Blanco, F.; Campos, J.

    1993-01-01

    This paper, describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT: It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate/phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the arrays is digitized by a 12-bit analog to digital converter and stored in a computer for its later analysis. The necessary software to store and display data has been developed. (Author)

  10. A high throughput 2 m normal incidence monochromator for SURF-II

    International Nuclear Information System (INIS)

    Ederer, D.L.; Cole, B.E.; West, J.B.

    1980-01-01

    The high intrinsic brightness of the circulating electron beam at SURF-II is used as the entrance slit for a two-meter normal incidence monochromator. A typical beam size for the electron beam is 100 μm high by 2 mm wide yielding an obserbed resolution of 0.4 Angstroem with a 200 μm exit slit and a 2400 lines/mm grating. The instrument accepts a beam with a 65 mrad horizontal divergence and a 10 mrad vertical divergence. A plane pre-mirror used near normal incidence reflects the incoming radiation onto the 2 m grating; this combination provides a horizontal exit beam, and enables the experiment to be located three meters from the orbit tangent point. With magnesium fluoride coated aluminium optics a flux of 2 x 10'' photon/s x Angstroem at 1200 Angstroem is observed with a 10 mA circulating current. A flux of 5 x 10 10 photon/s x Angstroem at 600 Angstroem is obserbed with an osmium coated grating and a 10 mA circulating current. Sample spectra of the angle-resolved photoelectron spectrum of CO are presented. (orig.)

  11. Reflection and transmission of normally incident full-vector X waves on planar interfaces

    KAUST Repository

    Salem, Mohamed; Bagci, Hakan

    2011-01-01

    The reflection and transmission of full-vector X waves normally incident on planar half-spaces and slabs are studied. For this purpose, X waves are expanded in terms of weighted vector Bessel beams; this new decomposition and reconstruction method

  12. Studies on normal incidence backscattering in nodule areas using the multibeam-hydrosweep system

    Digital Repository Service at National Institute of Oceanography (India)

    Pathak, D.; Chakraborty, B.

    The acoustic response from areas of varying nodule abundance and number densities in the Central Indian Ocean has been studied by using the echo peak amplitudes of the normal incidence beam in the Multibeam Hydrosweep system. It is observed...

  13. Energy dependence of ion-induced sputtering yields from monoatomic solids at normal incidence

    International Nuclear Information System (INIS)

    Yamamura, Yasunori; Tawara, Hiro.

    1995-03-01

    The yields of the ion-induced sputtering from monoatomic solids at normal incidence for various ion-target combinations are presented graphically as a function of the incident ion energy. In order to fill the lack of the experimental data, the sputtering yields are also calculated by the Monte Carlo simulation code ACAT for some ion-target combinations. Each graph shows available experimental data points and the ACAT data, together with the sputtering yields calculated by the present empirical formula, whose parameters are determined by the best-fit to available data. (author)

  14. High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100-300 Å spectral banda)

    Science.gov (United States)

    Widmann, K.; Beiersdorfer, P.; Magee, E. W.; Boyle, D. P.; Kaita, R.; Majeski, R.

    2014-11-01

    We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li+ or Li2 +, which radiate near 199 Å and 135 Å, respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 mÅ at the 200 Å setting and better than 40 mÅ for the 135-Å range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Å Li+ and 65 eV for the 135 Å Li2 + lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

  15. 3m Vacuum Ultraviolet Spectrometer with Optical Multichannel Detector

    International Nuclear Information System (INIS)

    Martin, P.; Peraza, C.; Blanco, F.; Campos, J.

    1993-01-01

    This paper describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT. It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate / phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the array is digitized by a 12-bit analog to digital converter and stored in a computer, for its later analysis. The necessary software to store and display data has been developed. (Author) 18 refs

  16. THE EFFECT OF WAIST CIRCUMFERENCES MORE THAN NORMAL ON THE INCIDENT OF CORONARY HEART DISEASE

    Directory of Open Access Journals (Sweden)

    Pria Wahyu

    2017-07-01

    Full Text Available Introduction: Coronary heart disease is known as the most common disease that causes mortality in the world, one of the examination to identify the risks of coronary heart disease is measuring waist circumference. The purpose of this study was to identify correlation between large waist circumferences and the incident of coroner heart disease. Method: Design used in this study was analytic observational (retrospective with cross sectional approach. There were 63 respondents which sampling by simple random sampling. The independent variable was waist circumferences and the dependent variable was coronary heart disease. Data were collected by direct observation then analyzed by spearman correlation statistic test with significance level α≤0.05. Result: The result showed that waist circumferences more than normal had significant correlation with the incident of coronary heart disease (p=0.02. Analysis: It can be concluded that there was correlation between waist circumferences more than normal and the incident of coronary heart disease to the clients with coroner cardiac disease. Discussion: Earlier screening and detection is needed to prevent coronary heart disease.

  17. Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) Slit-Jaw Imaging System

    Science.gov (United States)

    Wilkerson, P.; Champey, P. R.; Winebarger, A. R.; Kobayashi, K.; Savage, S. L.

    2017-12-01

    The Marshall Grazing Incidence X-ray Spectrometer is a NASA sounding rocket payload providing a 0.6 - 2.5 nm spectrum with unprecedented spatial and spectral resolution. The instrument is comprised of a novel optical design, featuring a Wolter1 grazing incidence telescope, which produces a focused solar image on a slit plate, an identical pair of stigmatic optics, a planar diffraction grating and a low-noise detector. When MaGIXS flies on a suborbital launch in 2019, a slit-jaw camera system will reimage the focal plane of the telescope providing a reference for pointing the telescope on the solar disk and aligning the data to supporting observations from satellites and other rockets. The telescope focuses the X-ray and EUV image of the sun onto a plate covered with a phosphor coating that absorbs EUV photons, which then fluoresces in visible light. This 10-week REU project was aimed at optimizing an off-axis mounted camera with 600-line resolution NTSC video for extremely low light imaging of the slit plate. Radiometric calculations indicate an intensity of less than 1 lux at the slit jaw plane, which set the requirement for camera sensitivity. We selected a Watec 910DB EIA charge-coupled device (CCD) monochrome camera, which has a manufacturer quoted sensitivity of 0.0001 lux at F1.2. A high magnification and low distortion lens was then identified to image the slit jaw plane from a distance of approximately 10 cm. With the selected CCD camera, tests show that at extreme low-light levels, we achieve a higher resolution than expected, with only a moderate drop in frame rate. Based on sounding rocket flight heritage, the launch vehicle attitude control system is known to stabilize the instrument pointing such that jitter does not degrade video quality for context imaging. Future steps towards implementation of the imaging system will include ruggedizing the flight camera housing and mounting the selected camera and lens combination to the instrument structure.

  18. Assessment of radiation doses due to normal operation, incidents and accidents of the final disposal facility

    International Nuclear Information System (INIS)

    Rossi, J.; Raiko, H.; Suolanen, V.; Ilvonen, M.

    1999-03-01

    Radiation doses for workers of the encapsulation and disposal facility and for inhabitants in the environment caused by the facility during its operation were considered. The study covers both the normal operation of the plant and some hypothetical incidents and accidents. Occupational radiation doses inside the plant during normal operation are based on the design basis, assuming that highest permitted dose levels are prevailing in control rooms during fuel transfer and encapsulation processes. Release through the ventilation stack is assumed to be filtered both in normal operation and in hypothetical incident and accident cases. Calculation of the offsite doses from normal operation is based on the hypothesis that one fuel pin per 100 fuel bundles for all batches of spent fuel transported to the encapsulation facility is leaking. The release magnitude in incidents and accidents is based on the event chains, which lead to loss of fuel pin tightness followed by a discharge of radionuclides into the handling chamber and to some degree through the ventilation stack into atmosphere. The weather data measured at the Olkiluoto meteorological mast was employed for calculating of offsite doses. Therefore doses could be calculated in a large amount of different dispersion conditions, the statistical frequencies of which have, been measured. Finally doses were combined into cumulative distributions, from which a dose value representing the 99.5 % confidence level, is presented. The dose values represent the exposure of a critical group, which is assumed to live at the distance of 200 meters from the encapsulation and disposal plant and thus it will receive the largest doses in most dispersion conditions. Exposure pathways considered were: cloudsnine, inhalation, groundshine and nutrition (milk of cow, meat of cow, green vegetables, grain and root vegetables). Nordic seasonal variation is included in ingestion dose models. The results obtained indicate that offsite doses

  19. High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100–300 Å spectral band

    Energy Technology Data Exchange (ETDEWEB)

    Widmann, K., E-mail: widmann1@llnl.gov; Beiersdorfer, P.; Magee, E. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Boyle, D. P.; Kaita, R.; Majeski, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15

    We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li{sup +} or Li{sup 2+}, which radiate near 199 Å and 135 Å, respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 mÅ at the 200 Å setting and better than 40 mÅ for the 135-Å range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Å Li{sup +} and 65 eV for the 135 Å Li{sup 2+} lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

  20. Analytical evaluation for the sputtering yield of monoatomic solids at normal ion incidence

    International Nuclear Information System (INIS)

    Shao Qiyun; Pan Zhengying

    1994-01-01

    A universal formula of sputtering yield for normal incidence of mono-energetic ions on single element targets is presented. The results based on this method are compared with the Monte Carlo simulation and the experimental data. By means of Wilcoxon two-sample paired signed rank test, the statistically significant difference of the above results is discussed

  1. A rotated transmission grating spectrometer for detecting spectral separation of doublet Na

    Energy Technology Data Exchange (ETDEWEB)

    Santosa, Ignatius Edi [Department of Physics Education, Sanata Dharma University, Paingan Maguwohardjo Depok Sleman, Yogyakarta 55281, Indonesia edi@usd.ac.id (Indonesia)

    2015-04-16

    Transmission gratings are usually used in a spectrometer for measuring the wavelength of light. In the common design, the position of the grating is perpendicular to the incident light. In order to increase the angular dispersion, in contrary to the common design, in this experiment the transmission grating was rotated. Due to the non-zero incident angle, the diffracted light was shifted. This rotated transmission grating spectrometer has been used to determine the separation of doublet Na. In this experiment, the diffraction angle was measured at various incident angles. The spectral separation of doublet Na was identified from the difference in the diffraction angle of two spectral lines. This spectral separation depends on the incident angle, the grating constant and the order of diffraction. As the effect of increasing the incident angle, a significant increase of the spectral separation can be achieved up to three fold.

  2. A rotated transmission grating spectrometer for detecting spectral separation of doublet Na

    International Nuclear Information System (INIS)

    Santosa, Ignatius Edi

    2015-01-01

    Transmission gratings are usually used in a spectrometer for measuring the wavelength of light. In the common design, the position of the grating is perpendicular to the incident light. In order to increase the angular dispersion, in contrary to the common design, in this experiment the transmission grating was rotated. Due to the non-zero incident angle, the diffracted light was shifted. This rotated transmission grating spectrometer has been used to determine the separation of doublet Na. In this experiment, the diffraction angle was measured at various incident angles. The spectral separation of doublet Na was identified from the difference in the diffraction angle of two spectral lines. This spectral separation depends on the incident angle, the grating constant and the order of diffraction. As the effect of increasing the incident angle, a significant increase of the spectral separation can be achieved up to three fold

  3. 4D space access neutron spectrometer 4SEASONS (SIKI)

    International Nuclear Information System (INIS)

    Kajimoto, Ryoichi; Nakamura, Mitsutaka

    2010-01-01

    The 4D Space Access Neutron Spectrometer (4SEASONS) is a high-intensity Fermi-chopper spectrometer. It is intended to provide high counting rate for thermal neutrons with medium resolution (ΔE/E i -6% at E=0) to efficiently collect weak inelastic signals from novel spin and lattice dynamics especially in high-T c superconductors and related materials. To achieve this goal, the spectrometer equips advanced instrumental design such as an elliptic-shaped converging neutron guide coated with high-Q c (m=3-4) supermirror, and long-length (2.5 m) 3 He position sensitive detectors (PSDs) arranged cylindrically inside the vacuum scattering chamber. Furthermore, the spectrometer is ready for multi-incident-energy measurements by the repetition rate multiplication method, which greatly improves the measurement efficiency. (author)

  4. The Harwell back-scattering spectrometer

    International Nuclear Information System (INIS)

    Windsor, C.G.; Bunce, L.J.; Borcherds, P.H.; Cole, I.; Fitzmaurice, M.; Johnson, D.A.G.; Sinclair, R.N.

    1976-01-01

    Neutron diffraction spectra in which both high resolution (Δ Q/Q approximately equal to 0.003) and high intensity are maintained up to scattering vectors as high as 30A -1 (sin theta/lambda = 2.5) have been obtained with the back-scattering spectrometer (BSS) recently installed on the Harwell electron linac. The theory behind the spectrometer design is described, and it is shown how the above resolution requirement leads to its basic features of a 12m incident flight path, a 2m scattering flight path and a scattering angle (2theta) acceptance from 165 0 to 175 0 . Examples of the resolution, intensity and background are given. It is shown that the problem of frame overlap may be overcome by using an absorbing filter. (author)

  5. Three new extreme ultraviolet spectrometers on NSTX-U for impurity monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Weller, M. E., E-mail: weller4@llnl.gov; Beiersdorfer, P.; Soukhanovskii, V. A.; Magee, E. W.; Scotti, F. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-11-15

    Three extreme ultraviolet (EUV) spectrometers have been mounted on the National Spherical Torus Experiment–Upgrade (NSTX-U). All three are flat-field grazing-incidence spectrometers and are dubbed X-ray and Extreme Ultraviolet Spectrometer (XEUS, 8–70 Å), Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS, 190–440 Å), and Metal Monitor and Lithium Spectrometer Assembly (MonaLisa, 50–220 Å). XEUS and LoWEUS were previously implemented on NSTX to monitor impurities from low- to high-Z sources and to study impurity transport while MonaLisa is new and provides the system increased spectral coverage. The spectrometers will also be a critical diagnostic on the planned laser blow-off system for NSTX-U, which will be used for impurity edge and core ion transport studies, edge-transport code development, and benchmarking atomic physics codes.

  6. High-flux normal incidence monochromator for circularly polarized synchrotron radiation

    International Nuclear Information System (INIS)

    Schaefers, F.; Peatman, W.; Eyers, A.; Heckenkamp, C.; Schoenhense, G.; Heinzmann, U.

    1986-01-01

    A 6.5-m normal incidence monochromator installed at the storage ring BESSY, which is optimized for a high throughput of circularly polarized off-plane radiation at moderate resolution is described. The monochromator employs two exit slits and is specially designed and used for low-signal experiments such as spin- and angle-resolved photoelectron spectroscopy on solids, adsorbates, free atoms, and molecules. The Monk--Gillieson mounting (plane grating in a convergent light beam) allows for large apertures with relatively little astigmatism. With two gratings, a flux of more than 10 11 photons s -1 bandwidth -1 (0.2--0.5 nm) with a circular polarization of more than 90% in the wavelength range from 35 to 675 nm is achieved

  7. An imaging proton spectrometer for short-pulse laser plasma experiments

    International Nuclear Information System (INIS)

    Chen Hui; Hazi, A. U.; Maren, R. van; Chen, S. N.; Le Pape, S.; Rygg, J. R.; Shepherd, R.; Fuchs, J.; Gauthier, M.

    2010-01-01

    The ultraintense short pulse laser pulses incident on solid targets can generate energetic protons. In addition to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better characterize these laser-produced protons, we designed and constructed a novel spectrometer that will not only measure proton energy distribution with high resolution but also provide its angular characteristics. The information obtained from this spectrometer compliments those from commonly used diagnostics including radiochromic film packs, CR39 nuclear track detectors, and nonimaging magnetic spectrometers. The basic characterizations and sample data from this instrument are presented.

  8. An imaging proton spectrometer for short-pulse laser plasma experiments

    Energy Technology Data Exchange (ETDEWEB)

    Chen Hui; Hazi, A. U.; Maren, R. van; Chen, S. N.; Le Pape, S.; Rygg, J. R.; Shepherd, R. [Lawrence Livermore National Laboratory, Livemore, California 94551 (United States); Fuchs, J.; Gauthier, M. [LULI Ecole Polytechnique, 91128 Palaiseau Cedex (France)

    2010-10-15

    The ultraintense short pulse laser pulses incident on solid targets can generate energetic protons. In addition to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better characterize these laser-produced protons, we designed and constructed a novel spectrometer that will not only measure proton energy distribution with high resolution but also provide its angular characteristics. The information obtained from this spectrometer compliments those from commonly used diagnostics including radiochromic film packs, CR39 nuclear track detectors, and nonimaging magnetic spectrometers. The basic characterizations and sample data from this instrument are presented.

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

    Energy Technology Data Exchange (ETDEWEB)

    Spoth, Katherine; /SUNY, Buffalo /SLAC

    2012-08-28

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

  10. Charged-particle magnetic-quadrupole spectrometer for neutron induced reactions

    International Nuclear Information System (INIS)

    Haight, R.C.; Grimes, S.M.; Tuckey, B.J.; Anderson, J.D.

    1975-01-01

    A spectrometer has been developed for measuring the charged particle production cross sections and spectra in neutron-induced reactions. The spectrometer consists of a magnetic quadrupole doublet which focuses the charged particles onto a silicon surface barrier detector telescope which is 2 meters or more from the irradiated sample. Collimators, shielding, and the large source-to-detector distance reduce the background enough to use the spectrometer with a 14-MeV neutron source producing 4 . 10 12 n/s. The spectrometer has been used in investigations of proton, deuteron, and alpha particle production by 14-MeV neutrons incident on various materials. Protons with energies as low as 1.1 MeV have been measured. The good resolution of the detectors has also made possible an improved measurement of the neutron- neutron scattering length from the 0 0 proton spectrum from deuteron breakup by 14-MeV neutrons

  11. Applicability of portable spectrometer for activity measurement of contaminated water and soil samples

    International Nuclear Information System (INIS)

    Krishnan, Narayani; Rekha, A.K.; Anilkumar, S.; Sharma, D.N.

    2011-01-01

    The absolute activity measurement is often necessary to assess the impact of radioactivity contamination due to various incidents. Commercially available portable spectrometer cum dose rate meter is used for the identification of radionuclides involved and associated dose rates. In this paper the authors discusses the study carried out on the applicability of portable spectrometer for absolute radioactivity measurements in water and soil matrices. The portable spectrometer and the methodology developed for activity estimation has been used in many insitu applications. (author)

  12. A Soft X-ray Spectrometer using a Highly Dispersive Multilayer Grating

    International Nuclear Information System (INIS)

    Warwick, Tony; Padmore, Howard; Voronov, Dmitriy; Yashchuk, Valeriy

    2010-01-01

    There is a need for higher resolution spectrometers as a tool for inelastic x-ray scattering. Currently, resolving power around R = 10,000 is advertised. Measured RIXS spectra are often limited by this instrumental resolution and higher resolution spectrometers using conventional gratings would be prohibitively large. We are engaged in a development program to build blazed multilayer grating structures for diffracting soft x-rays in high order. This leads to spectrometers with dispersion much higher than is possible using metal coated-gratings. The higher dispersion then provides higher resolution and the multilayer gratings are capable of operating away from grazing incidence as required. A spectrometer design is presented with a total length 3.8 m and capable of 10 5 resolving power.

  13. A Soft X-ray Spectrometer using a Highly Dispersive Multilayer Grating

    International Nuclear Information System (INIS)

    Warwick, Tony; Padmore, Howard; Voronov, Dmitriy; Yashchuk, Valeriy

    2010-01-01

    There is a need for higher resolution spectrometers as a tool for inelastic x-ray scattering. Currently, resolving power around R = 10,000 is advertised. Measured RIXS spectra are often limited by this instrumental resolution and higher resolution spectrometers using conventional gratings would be prohibitively large. We are engaged in a development program to build blazed multilayer grating structures for diffracting soft x-rays in high order. This leads to spectrometers with dispersion much higher than is possible using metal coated-gratings. The higher dispersion then provides higher resolution and the multilayer gratings are capable of operating away from grazing incidence as required. A spectrometer design is presented with a total length 3.8m and capable of 10 5 resolving power.

  14. Aplanatic telescopes based on Schwarzschild optical configuration: from grazing incidence Wolter-like x-ray optics to Cherenkov two-mirror normal incidence telescopes

    Science.gov (United States)

    Sironi, Giorgia

    2017-09-01

    At the beginning of XX century Karl Schwarzschild defined a method to design large-field aplanatic telescopes based on the use of two aspheric mirrors. The approach was then refined by Couder (1926) who, in order to correct for the astigmatic aberration, introduced a curvature of the focal plane. By the way, the realization of normal-incidence telescopes implementing the Schwarzschild aplanatic configuration has been historically limited by the lack of technological solutions to manufacture and test aspheric mirrors. On the other hand, the Schwarzschild solution was recovered for the realization of coma-free X-ray grazing incidence optics. Wolter-like grazing incidence systems are indeed free of spherical aberration, but still suffer from coma and higher order aberrations degrading the imaging capability for off-axis sources. The application of the Schwarzschild's solution to X-ray optics allowed Wolter to define an optical system that exactly obeys the Abbe sine condition, eliminating coma completely. Therefore these systems are named Wolter-Schwarzschild telescopes and have been used to implement wide-field X-ray telescopes like the ROSAT WFC and the SOHO X-ray telescope. Starting from this approach, a new class of X-ray optical system was proposed by Burrows, Burg and Giacconi assuming polynomials numerically optimized to get a flat field of view response and applied by Conconi to the wide field x-ray telescope (WFXT) design. The Schwarzschild-Couder solution has been recently re-discovered for the application to normal-incidence Cherenkov telescopes, thanks to the suggestion by Vassiliev and collaborators. The Italian Institute for Astrophysics (INAF) realized the first Cherenkov telescope based on the polynomial variation of the Schwarzschild configuration (the so-called ASTRI telescope). Its optical qualification was successfully completed in 2016, demonstrating the suitability of the Schwarzschild-like configuration for the Cherenkov astronomy requirements

  15. A multiplex coding imaging spectrometer for X-ray astronomy

    International Nuclear Information System (INIS)

    Rocchia, R.; Deschamps, J.Y.; Koch-Miramond, L.; Tarrius, A.

    1985-06-01

    The paper describes a multiplex coding system associated with a solid state spectrometer Si(Li) designed to be placed at the focus of a grazing incidence telescope. In this instrument the spectrometric and imaging functions are separated. The coding system consists in a movable mask with pseudo randomly distributed holes, located in the focal plane of the telescope. The pixel size lies in the range 100-200 microns. The close association of the coding system with a Si(Li) detector gives an imaging spectrometer combining the good efficiency (50% between 0,5 and 10 keV) and energy resolution (ΔE approximately 90 to 160 eV) of solid state spectrometers with the spatial resolution of the mask. Simulations and results obtained with a laboratory model are presented

  16. Orientation-dependent ion beam sputtering at normal incidence conditions in FeSiAl alloy

    International Nuclear Information System (INIS)

    Batic, Barbara Setina; Jenko, Monika

    2010-01-01

    The authors have performed Ar+ broad ion beam sputtering of a polycrystalline Fe-Si-Al alloy at normal incidence at energies varying from 6 to 10 keV. Sputtering results in the formation of etch pits, which can be classified in three shapes: triangular, rectangular, and square. As each grain of individual orientation exhibits a certain type of pattern, the etch pits were correlated with the crystal orientations by electron backscattered diffraction technique.

  17. Low power ion spectrometer for high counting rates

    International Nuclear Information System (INIS)

    Klein, J.W.; Dullenkopf, P.; Glasmachers, A.; Melbert, J.; Winkelnkemper, W.

    1980-01-01

    This report describes in detail the electronic concept for a time-of-flight (TOF) ion spectrometer for high counting rates and high dynamic range which can be used as a satellite instrument. The detection principle of the spectrometer is based on a time-of-flight and energy measurement for each incident ion. The ionmass is related to these two quantities by a simple equation. The described approach for the mass identification systems is using an analog fast-slow concept: The fast TOF-signal preselects the gainstep in the much slower energy channel. The conversion time of the mass identifier is approximately 10 -6 s and the dynamic range of the energy channel is better than 10 3 (20 keV to 25 MeV). The purpose of this study was to demonstrate the feasibility of a TOF-spectrometer capable to measure the ion composition in planetary magnetospheres. (orig.) [de

  18. A condensed matter electron momentum spectrometer with parallel detection in energy and momentum

    Energy Technology Data Exchange (ETDEWEB)

    Storer, P; Caprari, R S; Clark, S A.C.; Vos, M; Weigold, E

    1994-03-01

    An electron momentum spectrometer has been constructed which measures electron binding energies and momenta by fully determining the kinematics of the incident, scattered and ejected electrons resulting from (e,2e) ionizing collisions in a thin solid foil. The spectrometer operates with incident beam energies of 20-30 keV in an asymmetric, non-coplanar scattering geometry. Bethe ridge kinematics are used. The technique uses transmission through the target foil, but it is most sensitive to the surface from which the 1.2 keV electrons emerge, to a depth of about 5 nm. Scattered and ejected electron energies and azimuthal angles are detected in parallel using position sensitive detection, yielding true coincidence count rates of 6 Hz from a 5.5 nm thick evaporated carbon target and an incident beam current of around 100 nA. The energy resolution is approximately 1.3 eV and momentum resolution approximately 0.15 a{sub 0}{sup -1}. The energy resolution could readily be improved by monochromating the incident electron beam. 28 refs., 15 figs.

  19. A condensed matter electron momentum spectrometer with parallel detection in energy and momentum

    International Nuclear Information System (INIS)

    Storer, P.; Caprari, R.S.; Clark, S.A.C.; Vos, M.; Weigold, E.

    1994-03-01

    An electron momentum spectrometer has been constructed which measures electron binding energies and momenta by fully determining the kinematics of the incident, scattered and ejected electrons resulting from (e,2e) ionizing collisions in a thin solid foil. The spectrometer operates with incident beam energies of 20-30 keV in an asymmetric, non-coplanar scattering geometry. Bethe ridge kinematics are used. The technique uses transmission through the target foil, but it is most sensitive to the surface from which the 1.2 keV electrons emerge, to a depth of about 5 nm. Scattered and ejected electron energies and azimuthal angles are detected in parallel using position sensitive detection, yielding true coincidence count rates of 6 Hz from a 5.5 nm thick evaporated carbon target and an incident beam current of around 100 nA. The energy resolution is approximately 1.3 eV and momentum resolution approximately 0.15 a 0 -1 . The energy resolution could readily be improved by monochromating the incident electron beam. 28 refs., 15 figs

  20. Theory of emission spectra from metal films irradiated by low energy electrons near normal incidence

    International Nuclear Information System (INIS)

    Kretschmann, E.; Callcott, T.A.; Arakawa, E.T.

    1980-01-01

    The emission spectrum produced by low energy electrons incident on a rough metal surface has been calculated for a roughness auto-correlation function containing a prominent peak at a high wave vector. For low energy electrons near normal incidence, the high wavevector peak dominates the roughness coupled surface plasmon radiation (RCSPR) process. The calculation yields estimates of the ratio of RCSPR to transition radiation, the dependence of emission intensity on electron energy and the shape and position of the RCSPR peak. The most interesting result is that the high-wavevector roughness can split the RCSPR radiation into peaks lying above and below the asymptotic surface plasma frequency. The results are compared with data from Ag in the following paper. (orig.)

  1. Spectrometer of Cherenkov radiation rings with hodoscopic photomultipliers

    International Nuclear Information System (INIS)

    Abramov, V.V.; Alekseev, A.V.; Baldin, B.Yu.

    1983-01-01

    Characteristics of SKOCH Cherenkov radiation ring spectrometer intended for identification of π- and K-mesons and protons in a wide divergent beam in the pulse range of 5.5-30 GeV/s are investigated. The spectrometer detecting system is based on using the hodoscopic photoelectron multipliers (HPEM). The HPEM specific feature is that they have an extended cathode and permit to determine the coordinate of an incident photon by measuring the time of photoelectron drift to a dinode system. The spectrometer has been tested at the FODS facility in the secondary particle beam with angular divergence equal to 16x6 mrad and aperture of 400x200 mm in the pulse range of 6-20 GeV/s. The range of Cherenkov radiation angle detection is 40-100 mrad which corresponds to the particle velocity range of 0.996-1. The angular and radial aperture is 30 mrad, the diameter is 420 mm. The obtained velocity resolution is 6x10 -5

  2. A high resolution x-ray fluorescence spectrometer for near edge absorption studies

    International Nuclear Information System (INIS)

    Stojanoff, V.; Hamalainen, K.; Siddons, D.P.; Hastings, J.B.; Berman, L.E.; Cramer, S.; Smith, G.

    1991-01-01

    A high resolution fluorescence spectrometer using a Johann geometry in a back scattering arrangement was developed. The spectrometer, with a resolution of 0.3 eV at 6.5 keV, combined with an incident beam, with a resolution of 0.7 eV, form the basis of a high resolution instrument for measuring x-ray absorption spectra. The advantages of the instrument are illustrated with the near edge absorption spectrum of dysprosium nitrate. 10 refs., 4 figs

  3. Coupling of morphology to surface transport in ion-beam-irradiated surfaces: normal incidence and rotating targets

    International Nuclear Information System (INIS)

    Munoz-Garcia, Javier; Cuerno, Rodolfo; Castro, Mario

    2009-01-01

    Continuum models have proved their applicability to describe nanopatterns produced by ion-beam sputtering of amorphous or amorphizable targets at low and medium energies. Here we pursue the recently introduced 'hydrodynamic approach' in the cases of bombardment at normal incidence, or of oblique incidence onto rotating targets, known to lead to self-organized arrangements of nanodots. Our approach stresses the dynamical roles of material (defect) transport at the target surface and of local redeposition. By applying results previously derived for arbitrary angles of incidence, we derive effective evolution equations for these geometries of incidence, which are then numerically studied. Moreover, we show that within our model these equations are identical (albeit with different coefficients) in both cases, provided surface tension is isotropic in the target. We thus account for the common dynamics for both types of incidence conditions, namely formation of dots with short-range order and long-wavelength disorder, and an intermediate coarsening of dot features that improves the local order of the patterns. We provide for the first time approximate analytical predictions for the dependence of stationary dot features (amplitude and wavelength) on phenomenological parameters, that improve upon previous linear estimates. Finally, our theoretical results are discussed in terms of experimental data.

  4. Radiation effects in silicon and gallium arsenide solar cells using isotropic and normally incident radiation

    Science.gov (United States)

    Anspaugh, B. E.; Downing, R. G.

    1984-01-01

    Several types of silicon and gallium arsenide solar cells were irradiated with protons with energies between 50 keV and 10 MeV at both normal and isotropic incidence. Damage coefficients for maximum power relative to 10 MeV were derived for these cells for both cases of omni-directional and normal incidence. The damage coefficients for the silicon cells were found to be somewhat lower than those quoted in the Solar Cell Radiation Handbook. These values were used to compute omni-directional damage coefficients suitable for solar cells protected by coverglasses of practical thickness, which in turn were used to compute solar cell degradation in two proton-dominated orbits. In spite of the difference in the low energy proton damage coefficients, the difference between the handbook prediction and the prediction using the newly derived values was negligible. Damage coefficients for GaAs solar cells for short circuit current, open circuit voltage, and maximum power were also computed relative to 10 MeV protons. They were used to predict cell degradation in the same two orbits and in a 5600 nmi orbit. Results show the performance of the GaAs solar cells in these orbits to be superior to that of the Si cells.

  5. Doubly curved imaging Bragg crystal spectrometer for X-ray astronomy

    DEFF Research Database (Denmark)

    Byrnak, B. P.; Christensen, Finn Erland; Westergaard, Niels Jørgen Stenfeldt

    1985-01-01

    An X-ray spectrometer which is sensitive in the 0.5-7-keV energy range and is intended for use onboard astronomical satellites has been studied. The Bragg reflected rays from a doubly bent crystal positioned downstream of the focal plane of a grazing-incidence concentrator are focused along the a...

  6. The University of Colorado OSO-8 spectrometer experiment. I

    International Nuclear Information System (INIS)

    Bruner, E.C. Jr.

    1977-01-01

    The optical design of the high resolution ultraviolet spectrometer prepared for the OSO-8 spacecraft by the University of Colorado is discussed. The instrument is a conventional 1 m Ebert-Fastie spectrometer fed by a Cassegrainian telescope. The instrument operates in the spectral range 1200 A to about 2000 A with spectral resolution of order 0.02 A. Spatial resolution is about 2.5 sec normal to the direction of the slit and is selectable from about 3 sec to 15' along the direction of the slit. Time resolution for the single spectrometer channel is selectable according to the needs of an individual observation and is limited to a maximum sampling rate of 40 ms per data point. The instrument is controlled by an internal general purpose computer. In this paper the author develops the performance requirements of the spectrometer and attempts to highlight some of the tradeoffs available to the instrument designer. (Auth.)

  7. Precision tracking at high background rates with the ATLAS muon spectrometer

    CERN Document Server

    Hertenberger, Ralf; The ATLAS collaboration

    2012-01-01

    Since start of data taking the ATLAS muon spectrometer performs according to specification. End of this decade after the luminosity upgrade of LHC by a factor of ten the proportionally increasing background rates require the replacement of the detectors in the most forward part of the muon spectrometer to ensure high quality muon triggering and tracking at background hit rates of up to 15,kHz/cm$^2$. Square meter sized micromegas detectors together with improved thin gap trigger detectors are suggested as replacement. Micromegas detectors are intrinsically high rate capable. A single hit spatial resolution below 40,$mu$m has been shown for 250,$mu$m anode strip pitch and perpendicular incidence of high energy muons or pions. The ongoing development of large micromegas structures and their investigation under non-perpendicular incidence or in high background environments requires precise and reliable monitoring of muon tracks. A muon telescope consisting of six small micromegas works reliably and is presently ...

  8. Cervical cancer incidence after normal cytological sample in routine screening using SurePath, ThinPrep, and conventional cytology

    DEFF Research Database (Denmark)

    Rozemeijer, Kirsten; Naber, Steffie K; Penning, Corine

    2017-01-01

    of histo- and cytopathology in the Netherlands (PALGA), January 2000 to March 2013.Population Women with 5 924 474 normal screening samples (23 833 123 person years).Exposure Use of SurePath or ThinPrep versus conventional cytology as screening test.Main outcome measure 72 month cumulative incidence...

  9. Continuum modeling of ion-beam eroded surfaces under normal incidence: Impact of stochastic fluctuations

    International Nuclear Information System (INIS)

    Dreimann, Karsten; Linz, Stefan J.

    2010-01-01

    Graphical abstract: Deterministic surface pattern (left) and its stochastic counterpart (right) arising in a stochastic damped Kuramoto-Sivashinsky equation that serves as a model equation for ion-beam eroded surfaces and is systematically investigated. - Abstract: Using a recently proposed field equation for the surface evolution of ion-beam eroded semiconductor target materials under normal incidence, we systematically explore the impact of additive stochastic fluctuations that are permanently present during the erosion process. Specifically, we investigate the dependence of the surface roughness, the underlying pattern forming properties and the bifurcation behavior on the strength of the fluctuations.

  10. Spherical grating spectrometers

    Science.gov (United States)

    O'Donoghue, Darragh; Clemens, J. Christopher

    2014-07-01

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

  11. Incidence of ascariasis in gastric carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Woo; Rhee, Hak Song; Bahk, Yong Whee [St Mary' s Hospital Catholic Medical College, Seoul (Korea, Republic of)

    1972-09-15

    Prompted by the finding that the radiological incidence of small bowel ascariasis in the patient with gastric carcinoma was unexpectedly lower than the incidence in the normal population, a clinical study was performed to investigate possible relationship between gastric carcinoma and intestinal ascariasis. As a preliminary survey, we reviewed the radiological incidence of ascariasis in a total of 2,446 cases of upper GI series performed at the Department of Radiology, St Mary's Hospital Catholic Medical College. These included 1,573 normal subjects, 146 gastric carcinoma patients, 100 benign gastric ulcer and 249 duodenal ulcer patients and 378 other upper GI diseases. Following the preliminary study, a more accurate parasitologic study was conducted in another 578 normal subjects and 51 gastric carcinoma patients. The radiological incidences of ascaiasis in normal subjects and gastric carcinoma patients were 15.1% and 28.1%, respectively. The incidence of overall helminthiasis including ascaris lumbricoides, trichocephalus trichiurus and trichostrongyloides orientalis in normal subjects of the present series was 73.5%. This figure is virtually the same with 69.1% of the general population incidence reported by Kim, et al. (1971), but the incidence in gastric carcinoma patients was 94.1%. The high incidence pattern of overall helminthiasis in gastric carcinoma patients is, however, reversed as for as ascariasis is concerned. Thus, the incidence of ascariasis of gastric carcinoma patients was much lower than that of normal subjects (9.8% vs 19.4%). From the present observation, it is postulated that there can be some possible antagonistic relationship between evolution of gastric carcinoma and small bowel infestation of ascaris lumbricoides.

  12. Incidence of ascariasis in gastric carcinoma

    International Nuclear Information System (INIS)

    Kim, Jong Woo; Rhee, Hak Song; Bahk, Yong Whee

    1972-01-01

    Prompted by the finding that the radiological incidence of small bowel ascariasis in the patient with gastric carcinoma was unexpectedly lower than the incidence in the normal population, a clinical study was performed to investigate possible relationship between gastric carcinoma and intestinal ascariasis. As a preliminary survey, we reviewed the radiological incidence of ascariasis in a total of 2,446 cases of upper GI series performed at the Department of Radiology, St Mary's Hospital Catholic Medical College. These included 1,573 normal subjects, 146 gastric carcinoma patients, 100 benign gastric ulcer and 249 duodenal ulcer patients and 378 other upper GI diseases. Following the preliminary study, a more accurate parasitologic study was conducted in another 578 normal subjects and 51 gastric carcinoma patients. The radiological incidences of ascaiasis in normal subjects and gastric carcinoma patients were 15.1% and 28.1%, respectively. The incidence of overall helminthiasis including ascaris lumbricoides, trichocephalus trichiurus and trichostrongyloides orientalis in normal subjects of the present series was 73.5%. This figure is virtually the same with 69.1% of the general population incidence reported by Kim, et al. (1971), but the incidence in gastric carcinoma patients was 94.1%. The high incidence pattern of overall helminthiasis in gastric carcinoma patients is, however, reversed as for as ascariasis is concerned. Thus, the incidence of ascariasis of gastric carcinoma patients was much lower than that of normal subjects (9.8% vs 19.4%). From the present observation, it is postulated that there can be some possible antagonistic relationship between evolution of gastric carcinoma and small bowel infestation of ascaris lumbricoides

  13. Using a portable ion mobility spectrometer to screen dietary supplements for sibutramine.

    Science.gov (United States)

    Dunn, Jamie D; Gryniewicz-Ruzicka, Connie M; Kauffman, John F; Westenberger, Benjamin J; Buhse, Lucinda F

    2011-02-20

    In response to recent incidents of undeclared sibutramine, an appetite suppressant found in dietary supplements, we developed a method to detect sibutramine using hand-held ion mobility spectrometers with an analysis time of 15 s. Ion mobility spectrometry is a high-throughput and sensitive technique that has been used for illicit drug, explosive, volatile organic compound and chemical warfare detection. We evaluated a hand-held ion mobility spectrometer as a tool for the analysis of supplement extracts containing sibutramine. The overall instrumental limit of detection of five portable ion mobility spectrometers was 2 ng of sibutramine HCl. When sample extractions containing 30 ng/μl or greater of sibutramine were analyzed, saturation of the ionization chamber of the spectrometer occurred and the instrument required more than three cleaning cycles to remove the drug. Hence, supplement samples suspected of containing sibutramine should be prepared at concentrations of 2-20 ng/μl. To obtain this target concentration range for products containing unknown amounts of sibutramine, we provided a simple sample preparation procedure, allowing the U.S. Food and Drug Administration or other agencies to screen products using the portable ion mobility spectrometer. Published by Elsevier B.V.

  14. Short-wavelength soft-x-ray laser pumped in double-pulse single-beam non-normal incidence

    International Nuclear Information System (INIS)

    Zimmer, D.; Ros, D.; Guilbaud, O.; Habib, J.; Kazamias, S.; Zielbauer, B.; Bagnoud, V.; Ecker, B.; Aurand, B.; Kuehl, T.; Hochhaus, D. C.; Neumayer, P.

    2010-01-01

    We demonstrated a 7.36 nm Ni-like samarium soft-x-ray laser, pumped by 36 J of a neodymium:glass chirped-pulse amplification laser. Double-pulse single-beam non-normal-incidence pumping was applied for efficient soft-x-ray laser generation. In this case, the applied technique included a single-optic focusing geometry for large beam diameters, a single-pass grating compressor, traveling-wave tuning capability, and an optimized high-energy laser double pulse. This scheme has the potential for even shorter-wavelength soft-x-ray laser pumping.

  15. Digital PIV Measurements of Acoustic Particle Displacements in a Normal Incidence Impedance Tube

    Science.gov (United States)

    Humphreys, William M., Jr.; Bartram, Scott M.; Parrott, Tony L.; Jones, Michael G.

    1998-01-01

    Acoustic particle displacements and velocities inside a normal incidence impedance tube have been successfully measured for a variety of pure tone sound fields using Digital Particle Image Velocimetry (DPIV). The DPIV system utilized two 600-mj Nd:YAG lasers to generate a double-pulsed light sheet synchronized with the sound field and used to illuminate a portion of the oscillatory flow inside the tube. A high resolution (1320 x 1035 pixel), 8-bit camera was used to capture double-exposed images of 2.7-micron hollow silicon dioxide tracer particles inside the tube. Classical spatial autocorrelation analysis techniques were used to ascertain the acoustic particle displacements and associated velocities for various sound field intensities and frequencies. The results show that particle displacements spanning a range of 1-60 microns can be measured for incident sound pressure levels of 100-130 dB and for frequencies spanning 500-1000 Hz. The ability to resolve 1 micron particle displacements at sound pressure levels in the 100 dB range allows the use of DPIV systems for measurement of sound fields at much lower sound pressure levels than had been previously possible. Representative impedance tube data as well as an uncertainty analysis for the measurements are presented.

  16. Cumulative increased risk of incident type 2 diabetes mellitus with increasing triglyceride glucose index in normal-weight people: The Rural Chinese Cohort Study.

    Science.gov (United States)

    Zhang, Ming; Wang, Bingyuan; Liu, Yu; Sun, Xizhuo; Luo, Xinping; Wang, Chongjian; Li, Linlin; Zhang, Lu; Ren, Yongcheng; Zhao, Yang; Zhou, Junmei; Han, Chengyi; Zhao, Jingzhi; Hu, Dongsheng

    2017-03-01

    Risk of type 2 diabetes mellitus (T2DM) is increased in metabolically obese but normal-weight people. However, we have limited knowledge of how to prevent T2DM in normal-weight people. We aimed to evaluate the association between triglyceride glucose (TyG) index and incident T2DM among normal-weight people in rural China. We included data from 5706 people with normal body mass index (BMI) (18.5-23.9 kg/m 2 ) without baseline T2DM in a rural Chinese cohort followed for a median of 6.0 years. A Cox proportional-hazard model was used to assess the risk of incident T2DM by quartiles of TyG index and difference in TyG index between follow-up and baseline (TyG-D), estimating hazard ratios (HRs) and 95% confidence intervals (CIs). A generalized additive plot was used to show the nonparametric smoothed exposure-response association between risk of T2DM and TyG index as a continuous variable. TyG was calculated as ln [fasting triglyceride level (mg/dl) × fasting plasma glucose level (mg/dl)/2]. Risk of incident T2DM was increased with quartiles 2, 3 and 4 versus quartile 1 of TyG index (adjusted HR [aHR] 2.48 [95% CI 1.20-5.11], 3.77 [1.83-7.79], and 5.30 [2.21-12.71], P trend  index). Risk of incident T2DM was increased with quartile 4 versus quartile 1 of TyG-D (aHR 3.91 [2.22-6.87]). The results were consistent when analyses were restricted to participants without baseline metabolic syndrome and impaired fasting glucose level. The generalized additive plot showed cumulative increased risk of T2DM with increasing TyG index. Risk of incident T2DM is increased with increasing TyG index among rural Chinese people, so the index might be an important indicator for identifying people at high risk of T2DM.

  17. Correlation spectrometer

    Science.gov (United States)

    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.

  18. Incidence angle normalization of radar backscatter data

    Science.gov (United States)

    NASA’s Soil Moisture Passive Active (SMAP) satellite (~2014) will include a radar system that will provide L-band multi-polarization backscatter at a constant incidence angle of 40º. During the pre-launch phase of the project there is a need for observations that will support the radar-based soil mo...

  19. Setup of Mössbauer spectrometers at RCPTM

    Science.gov (United States)

    Pechoušek, J.; Jančík, D.; Frydrych, J.; Navařík, J.; Novák, P.

    2012-10-01

    Setup of Mössbauer spectrometers (MS) for structural, phase, and magnetic characterization of iron-or tin-containing samples is presented. This comprehensive line of 57Fe and 119Sn Mössbauer spectrometers covers transmission spectrometers (TMS) for roomtemperature (RT) measurements, temperature dependent measurements and measurements in an external magnetic field. An RT Conversion Electron/Conversion X-ray Mössbauer technique (CEMS/CXMS) is also available. The main concept of the RT MS is a table-top spectrometric bench with a control unit based on special-purpose hardware or standard PC platform. The first way offers a compact design and PC independent spectra collection system. The second setup, a PC-based system, which uses commercial devices and LabVIEW software, offers easy customization and enables advancement in spectrometer construction. The both types of control systems are able to operate special parts (velocity transducers, gamma-ray detectors) of unusual spectrometric benches. The standard velocity axis range is up to ±20 mm/s with a maximum nonlinearity of 0.1%. Applicable measuring conditions of presented TMSs cover a cryogenic temperature range from 1.5 up to 300 K and high temperature range from RT up to 1000 °C. With in-field low-temperature MS, we are able to analyze samples normally in the external magnetic fields up to 8 T (in temperature interval from 1.5 up to 300 K). In addition, special modes of measurements can be applied including backscattering gamma-ray geometry or measurement in an inert or controlled-humidity atmosphere. Technical details and construction aspects of spectrometers are presented.

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  1. Soft X-ray images of the solar corona using normal incidence optics

    Science.gov (United States)

    Bruner, M. E.; Haisch, B. M.; Brown, W. A.; Acton, L. W.; Underwood, J. H.

    1988-01-01

    A solar coronal loop system has been photographed in soft X-rays using a normal incidence telescope based on multilayer mirror technology. The telescope consisted of a spherical objective mirror of 4 cm aperture and 1 m focal length, a film cassette, and a focal plane shutter. A metallized thin plastic film filter was used to exclude visible light. The objective mirror was covered with a multilayer coating consisting of alternating layers of tungsten and carbon whose combined thicknesses satisfied the Bragg diffraction condition for 44 A radiation. The image was recorded during a rocket flight on October 25, 1985 and was dominated by emission lines arising from the Si XII spectrum. The rocket also carried a high resolution soft X-ray spectrograph that confirmed the presence of Si XII line radiation in the source. This image represents the first successful use of multilayer technology for astrophysical observations.

  2. A finite element propagation model for extracting normal incidence impedance in nonprogressive acoustic wave fields

    Science.gov (United States)

    Watson, Willie R.; Jones, Michael G.; Tanner, Sharon E.; Parrott, Tony L.

    1995-01-01

    A propagation model method for extracting the normal incidence impedance of an acoustic material installed as a finite length segment in a wall of a duct carrying a nonprogressive wave field is presented. The method recasts the determination of the unknown impedance as the minimization of the normalized wall pressure error function. A finite element propagation model is combined with a coarse/fine grid impedance plane search technique to extract the impedance of the material. Results are presented for three different materials for which the impedance is known. For each material, the input data required for the prediction scheme was computed from modal theory and then contaminated by random error. The finite element method reproduces the known impedance of each material almost exactly for random errors typical of those found in many measurement environments. Thus, the method developed here provides a means for determining the impedance of materials in a nonprogressirve wave environment such as that usually encountered in a commercial aircraft engine and most laboratory settings.

  3. Signal-to-noise analysis of a birefringent spectral zooming imaging spectrometer

    Science.gov (United States)

    Li, Jie; Zhang, Xiaotong; Wu, Haiying; Qi, Chun

    2018-05-01

    Study of signal-to-noise ratio (SNR) of a novel spectral zooming imaging spectrometer (SZIS) based on two identical Wollaston prisms is conducted. According to the theory of radiometry and Fourier transform spectroscopy, we deduce the theoretical equations of SNR of SZIS in spectral domain with consideration of the incident wavelength and the adjustable spectral resolution. An example calculation of SNR of SZIS is performed over 400-1000 nm. The calculation results indicate that SNR with different spectral resolutions of SZIS can be optionally selected by changing the spacing between the two identical Wollaston prisms. This will provide theoretical basis for the design, development and engineering of the developed imaging spectrometer for broad spectrum and SNR requirements.

  4. Very high coronary artery calcium score with normal myocardial perfusion SPECT imaging is associated with a moderate incidence of severe coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Yuoness, Salem A.; Goha, Ahmed M.; Romsa, Jonathan G.; Akincioglu, Cigdem; Warrington, James C.; Datta, Sudip; Gambhir, Sanjay; Urbain, Jean-Luc C.; Vezina, William C. [London Health Sciences Centre, Department of Nuclear Medicine, London, ON (Canada); Massel, David R. [London Health Sciences Centre, Division of Cardiology, London, ON (Canada); Martell, Rafael [Private Practice, London, ON (Canada)

    2015-09-15

    Myocardial perfusion imaging (MPI) has limitations in the presence of balanced multivessel disease (MVD) and left main (LM) coronary artery disease, occasionally resulting in false-normal results despite the high cardiovascular risk associated with this condition. The purpose of this study was to assess the incidence of severe coronary artery disease (CAD) in the presence of a very high Agatston coronary artery calcium (CAC) score (>1,000) in stable symptomatic patients without known CAD but with normal MPI results. A total of 2,659 prospectively acquired consecutive patients were referred for MPI and evaluation of CAC score by CT. Of this patient population, 8 % (222/2,659) had ischemia without myocardial infarction (MI) on MPI and 11 % (298/2,659) had abnormal MPI (MI and/or ischemia). On presentation 1 % of the patients (26/2,659) were symptomatic, had a CAC score >1,000 and normal MPI results. The definition of normal MPI was strict and included a normal hemodynamic response without ischemic ECG changes and normal imaging, particularly absence of transient ischemic dilation. All of these 26 patients with a CAC score >1,000 and normal MPI findings underwent cardiac catheterization. Of these 26 patients, 58 % (15/26) had severe disease (≥70 % stenosis) leading to revascularization. Of this group, 47 % (7/15) underwent percutaneous intervention, and 53 % (8/15) underwent coronary artery bypass grafting. All of these 15 patients had either MVD (14/15) or LM coronary artery disease (1/15), and represented 0.6 % (15/2,659) of all referred patients (95 % CI 0.3 - 0.9 %). The majority, 90 % (8/9), had severe CAD with typical chest pain. A very high CAC score (>1,000) with normal MPI in a small subset of symptomatically stable patients was associated with a moderate incidence of severe CAD (95 % CI 37 - 77 %). Larger studies and/or a meta-analysis of small studies are needed to more precisely estimate the incidence of CAD in this population. This study also supports

  5. Cryogenic system for a superconducting spectrometer

    International Nuclear Information System (INIS)

    Porter, J.

    1983-03-01

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

  6. Prototype Neutron Energy Spectrometer

    International Nuclear Information System (INIS)

    Mitchell, Stephen; Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ronald

    2010-01-01

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

  7. Prototype Neutron Energy Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Mitchell, Sanjoy Mukhopadhyay, Richard Maurer, Ronald Wolff

    2010-06-16

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

  8. A Numerical Theory for Impedance Education in Three-Dimensional Normal Incidence Tubes

    Science.gov (United States)

    Watson, Willie R.; Jones, Michael G.

    2016-01-01

    A method for educing the locally-reacting acoustic impedance of a test sample mounted in a 3-D normal incidence impedance tube is presented and validated. The unique feature of the method is that the excitation frequency (or duct geometry) may be such that high-order duct modes may exist. The method educes the impedance, iteratively, by minimizing an objective function consisting of the difference between the measured and numerically computed acoustic pressure at preselected measurement points in the duct. The method is validated on planar and high-order mode sources with data synthesized from exact mode theory. These data are then subjected to random jitter to simulate the effects of measurement uncertainties on the educed impedance spectrum. The primary conclusions of the study are 1) Without random jitter the method is in excellent agreement with that for known impedance samples, and 2) Random jitter that is compatible to that found in a typical experiment has minimal impact on the accuracy of the educed impedance.

  9. Evolution of porous network in GaSb under normally incident 60 keV Ar{sup +}-ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Datta, D.P. [SUNAG Laboratory, Institute of Physics, Bhubaneswar 751 005, Odisha (India); Kanjilal, A. [Department of Physics, Shiv Nadar University, Gautam Budh Nagar 203 207, Uttar Pradesh (India); Garg, S.K. [SUNAG Laboratory, Institute of Physics, Bhubaneswar 751 005, Odisha (India); Sahoo, P.K. [School of Physical Sciences, National Institute of Science Education and Research, Bhubaneswar 751 005, Odisha (India); Satpati, B. [Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India); Kanjilal, D. [Inter-University Accelerator Center, Aruna Asaf Ali Marg, New Delhi 110 067 (India); Som, T., E-mail: tsom@iopb.res.in [SUNAG Laboratory, Institute of Physics, Bhubaneswar 751 005, Odisha (India)

    2014-08-15

    Highlights: • We show the evolution of a nanoporous layer in GaSb under Ar{sup +}-ion bombardment at normal incidence in the hitherto unexplored high fluence regime, namely 7 × 10{sup 16}–3 × 10{sup 18} ions cm{sup −2}. • Fluence dependent formation and growth of patches on top of the nanoporous layer is demonstrated by scanning electron microscopy. • We also show high amount of oxidation of such ion-beam-generated nanoporous structures, with formation of Ga{sub 2}O{sub 3} and Sb{sub 2}O{sub 3}. • Our study reveals the presence of nanocrystallites within the porous layer even at the highest fluence used in the experiment. • We interpret the experimental observations through a qualitative model where we take into account the effect of re-deposition of atoms sputtered from the nanoporous layer during Ar{sup +}-ion irradiation of GaSb. - Abstract: GaSb(1 0 0) samples were irradiated with 60 keV Ar{sup +}-ions at normal incidence for fluences in the range of 7 × 10{sup 16} to 3 × 10{sup 18} ions cm{sup −2} at room temperature, showing gradual evolution of a porous surface layer containing interconnected nanofibers. In particular, fluence dependent formation of patches on the nanoporous layer is observed by scanning electron microscopy. Combined results of grazing incidence x-ray diffraction and transmission electron microscopy reveal the presence of nanocrystallites in the porous structures. Compositional analysis by x-ray photoelectron spectroscopy indicates the development of oxide phases, mainly Ga{sub 2}O{sub 3} and Sb{sub 2}O{sub 3} where the former increases with fluence. We have proposed a model addressing a competition between ion-induced-defect driven growth of the nanoporous layer and redeposition of sputtered target atoms on the growing layer.

  10. Monolithic spectrometer

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-01-01

    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.

  11. Influence of the coupling between an atmospheric pressure ion mobility spectrometer and the low pressure ion inlet of a mass spectrometer on the mobility measurement

    Directory of Open Access Journals (Sweden)

    Gunzer Frank

    2016-01-01

    Full Text Available Ion mobility spectrometers (IMS are versatile gas analyzers. Due to their small size and robustness, combined with a very high sensitivity, they are often used in gas sensing applications such as environmental monitoring. In order to improve the selectivity, they are typically combined with a mass spectrometer (MS. Since IMS works at atmospheric pressure, and MS works at vacuum, a special interface reducing the pressure over normally two stages has to be used. In this paper the influence of this coupling of different pressure areas on the IMS signal will be analyzed with help of finite elements method simulations.

  12. Reflection and transmission of full-vector X-waves normally incident on dielectric half spaces

    KAUST Repository

    Salem, Mohamed

    2011-08-01

    The reflection and transmission of full-vector X-Waves incident normally on a planar interface between two lossless dielectric half-spaces are investigated. Full-vector X-Waves are obtained by superimposing transverse electric and magnetic polarization components, which are derived from the scalar X-Wave solution. The analysis of transmission and reflection is carried out via a straightforward but yet effective method: First, the X-Wave is decomposed into vector Bessel beams via the Bessel-Fourier transform. Then, the reflection and transmission coefficients of the beams are obtained in the spectral domain. Finally, the transmitted and reflected X-Waves are obtained via the inverse Bessel-Fourier transform carried out on the X-wave spectrum weighted with the corresponding coefficient. © 2011 IEEE.

  13. Time-of-flight spectrometer for the measurement of gamma correlated neutron spectra

    International Nuclear Information System (INIS)

    Andriashin, A.V.; Devkin, B.V.; Lychagin, A.A.; Minko, J.V.; Mironov, A.N.; Nesterenko, V.S.; Sztaricskai, T.; Petoe, G.; Vasvary, L.

    1986-01-01

    A time-of-flight spectrometer for the measurement of gamma correlated neutron spectra from (n,xnγ) reactions is described. The operation and the main parameters are discussed. The resolution in the neutron channel is 2.2 ns/m at the 150 keV neutron energy threshold. A simultaneous measurement of the time-of-flight and amplitude distributions makes it possible to study gamma correlated neutron spectra as well as the prompt gamma spectra in coincidence with selected energy neutrons. In order to test the spectrometer, measurements of the neutron spectrum in coincidence with the 846 keV gamma line of 56 Fe were carried out at an incident neutron energy of 14.1 MeV. (Auth.)

  14. The use of vanadium as a scattering standard for pulsed source neutron spectrometers

    International Nuclear Information System (INIS)

    Mayers, J.

    1983-06-01

    The Gaussian approximation for multiphonon cross-sections has been used in a calculation of the variation of vanadium cross-sections with incident neutron energy. The results show that vanadium behaves as an elastic scatterer to within a few percent on pulsed neutron spectrometers with incident neutron energies up to 1 eV. There is a calculated anisotropy in the scattering of 8%. It is found that the scattering properties of vanadium at 77K and 293K differ by a maximum of 1% except for neutron energies < 15 meV. (author)

  15. MAXED, a computer code for the deconvolution of multisphere neutron spectrometer data using the maximum entropy method

    International Nuclear Information System (INIS)

    Reginatto, M.; Goldhagen, P.

    1998-06-01

    The problem of analyzing data from a multisphere neutron spectrometer to infer the energy spectrum of the incident neutrons is discussed. The main features of the code MAXED, a computer program developed to apply the maximum entropy principle to the deconvolution (unfolding) of multisphere neutron spectrometer data, are described, and the use of the code is illustrated with an example. A user's guide for the code MAXED is included in an appendix. The code is available from the authors upon request

  16. Energy dependence of angular distributions of sputtered particles by ion-beam bombardment at normal incidence

    International Nuclear Information System (INIS)

    Matsuda, Yoshinobu; Ueda, Yasutoshi; Uchino, Kiichiro; Muraoka, Katsunori; Maeda, Mitsuo; Akazaki, Masanori; Yamamura, Yasunori.

    1986-01-01

    The angular distributions of sputtered Fe-atoms were measured using the laser fluorescence technique during Ar-ion bombardment for energies of 0.6, 1, 2 and 3 keV at normal incidence. The measured cosine distribution at 0.6 keV progressively deviated to an over-cosine distribution at higher energies, and at 3 keV the angular distribution was an overcosine distribution of about 20 %. The experimental results agree qualitatively with calculations by a recent computer simulation code, ACAT. The results are explained by the competition between surface scattering and the effects of primary knock-on atoms, which tend to make the angular distributions over-cosine and under-cosine, respectively. (author)

  17. Multidimensional spectrometer

    Science.gov (United States)

    Zanni, Martin Thomas; Damrauer, Niels H.

    2010-07-20

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

  18. Small angle spectrometers: Summary

    International Nuclear Information System (INIS)

    Courant, E.; Foley, K.J.; Schlein, P.E.

    1986-01-01

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

  19. USE OF PORTABLE GAMMA SPECTROMETERS FOR IDENTIFYING PERSONS EXPOSED IN A NUCLEAR CRITICALITY

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K. G. [Y-12 National Security Complex; Gose, B. T. [Y-12 National Security Complex; Bogard, James S [ORNL

    2009-01-01

    At Y-12 triage-style assessments are used to identify persons potentially exposed to high doses from criticality accident radiations using portable instruments by assessing the presence of activated sodium atoms in a person's blood. Historically, simple hand-held Geiger-Mueller (G-M) probes were used for these purposes although it was recognized that, since these instruments contain no information on incident photon energy, it was impossible to differentiate between photons emitted by contamination on the potentially exposed worker from activation of sodium in the person s blood. This works examines the use of a portable gamma spectrometer for assessing blood sodium activation. Irradiations of a representative phantom were performed using two neutron source configurations (unmoderated and polyethylene-moderated 252Cf) and measurements were made using the spectrometer and a G-M detector following irradiation. Detection limits in terms of personnel neutron dose are given for two neutron fields representing metaland solution criticality spectra. Both Geiger-Mueller and spectrometer results indicate a low minimum detectable neutron dose indicating that both instrument are useful as an emergency response instrument. The spectrometer has the added benefit of discriminating between surface contamination and blood sodium activation.

  20. USE OF PORTABLE GAMMA SPECTROMETERS FOR IDENTIFYING PERSONS EXPOSED IN A NUCLEAR CRITICALITY

    International Nuclear Information System (INIS)

    Veinot, K.G.; Gose, B.T.; Bogard, James S.

    2009-01-01

    At Y-12 triage-style assessments are used to identify persons potentially exposed to high doses from criticality accident radiations using portable instruments by assessing the presence of activated sodium atoms in a person's blood. Historically, simple hand-held Geiger-Mueller (G-M) probes were used for these purposes although it was recognized that, since these instruments contain no information on incident photon energy, it was impossible to differentiate between photons emitted by contamination on the potentially exposed worker from activation of sodium in the persons blood. This works examines the use of a portable gamma spectrometer for assessing blood sodium activation. Irradiations of a representative phantom were performed using two neutron source configurations (unmoderated and polyethylene-moderated 252Cf) and measurements were made using the spectrometer and a G-M detector following irradiation. Detection limits in terms of personnel neutron dose are given for two neutron fields representing metal and solution criticality spectra. Both Geiger-Mueller and spectrometer results indicate a low minimum detectable neutron dose indicating that both instrument are useful as an emergency response instrument. The spectrometer has the added benefit of discriminating between surface contamination and blood sodium activation.

  1. Time-of-flight spectrometer for the measurement of gamma correlated neutron spectra

    International Nuclear Information System (INIS)

    Andryashin, A.V.; Devlein, B.V.; Lychagin, A.A.; Minko, Y.V.; Mironov, A.N.; Nesterenko, V.S.

    1986-01-01

    A time-of-flight spectrometer for the measurement of gamma correlated neutron spectra form (n,xnγ) reactions is described. The operation and the main parameters are discussed. The resolution in the neutron channel is 2.2 ns/m at the 150 keV neutron energy threshold. A simultaneous measurement of the time-of-flight and amplitude distributions makes it possible to study gamma correlated neutron spectra as well as the prompt gamma spectra in coincidence with selected energy neutrons. In order to test the spectrometer, measurements of the neutron spectrum in coincidence with the 846 keV gamma line of 56 Fe were carried out at an incident neutron energy of 14.1 MeV. (author). 3 figs., 6 refs

  2. The SPEDE spectrometer

    Science.gov (United States)

    Papadakis, P.; Cox, D. M.; O'Neill, G. G.; Borge, M. J. G.; Butler, P. A.; Gaffney, L. P.; Greenlees, P. T.; Herzberg, R.-D.; Illana, A.; Joss, D. T.; Konki, J.; Kröll, T.; Ojala, J.; Page, R. D.; Rahkila, P.; Ranttila, K.; Thornhill, J.; Tuunanen, J.; Van Duppen, P.; Warr, N.; Pakarinen, J.

    2018-03-01

    The electron spectrometer, SPEDE, has been developed and will be employed in conjunction with the Miniball spectrometer at the HIE-ISOLDE facility, CERN. SPEDE allows for direct measurement of internal conversion electrons emitted in-flight, without employing magnetic fields to transport or momentum filter the electrons. Together with the Miniball spectrometer, it enables simultaneous observation of γ rays and conversion electrons in Coulomb excitation experiments using radioactive ion beams.

  3. Light trapping for emission from a photovoltaic cell under normally incident monochromatic illumination

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Yasuhiko, E-mail: takeda@mosk.tytlabs.co.jp; Iizuka, Hideo; Mizuno, Shintaro; Hasegawa, Kazuo; Ichikawa, Tadashi; Ito, Hiroshi; Kajino, Tsutomu [Toyota Central Research and Development Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan); Ichiki, Akihisa; Motohiro, Tomoyoshi [Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)

    2014-09-28

    We have theoretically demonstrated a new light-trapping mechanism to reduce emission from a photovoltaic (PV) cell used for a monochromatic light source, which improves limiting conversion efficiency determined by the detailed balance. A multilayered bandpass filter formed on the surface of a PV cell has been found to prevent the light generated inside by radiative recombination from escaping the cell, resulting in a remarkable decrease of the effective solid angle for the emission. We have clarified a guide to design a suitable configuration of the bandpass filter and achieved significant reduction of the emission. The resultant gain in monochromatic conversion efficiency in the radiative limit due to the optimally designed 18-layerd bandpass filters is as high as 6% under normally incident 1064 nm illumination of 10 mW/cm²~ 1 kW/cm², compared with the efficiency for the perfect anti-reflection treatment to the surface of a conventional solar cell.

  4. A design of a high speed dual spectrometer by single line scan camera

    Science.gov (United States)

    Palawong, Kunakorn; Meemon, Panomsak

    2018-03-01

    A spectrometer that can capture two orthogonal polarization components of s light beam is demanded for polarization sensitive imaging system. Here, we describe the design and implementation of a high speed spectrometer for simultaneous capturing of two orthogonal polarization components, i.e. vertical and horizontal components, of light beam. The design consists of a polarization beam splitter, two polarization-maintain optical fibers, two collimators, a single line-scan camera, a focusing lens, and a reflection blaze grating. The alignment of two beam paths was designed to be symmetrically incident on the blaze side and reverse blaze side of reflection grating, respectively. The two diffracted beams were passed through the same focusing lens and focused on the single line-scan sensors of a CMOS camera. The two spectra of orthogonal polarization were imaged on 1000 pixels per spectrum. With the proposed setup, the amplitude and shape of the two detected spectra can be controlled by rotating the collimators. The technique for optical alignment of spectrometer will be presented and discussed. The two orthogonal polarization spectra can be simultaneously captured at a speed of 70,000 spectra per second. The high speed dual spectrometer can simultaneously detected two orthogonal polarizations, which is an important component for the development of polarization-sensitive optical coherence tomography. The performance of the spectrometer have been measured and analyzed.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Sadaoki, E-mail: kojima-s@ile.osaka-u.ac.jp; 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 [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Nishimura, Yasuhiko; Togawa, Hiromi [Toyota Technical Development Corporation, 1-21 Imae, Hanamoto-cho, Toyota, Aichi 470-0334 (Japan); Ozaki, Tetsuo [National Institute for Fusion Science, 322-6 Oroshicho, Toki, Gifu 509-5292 (Japan); Kato, Ryukou [The Institute of Science and Industrial Research, Osaka University, 2-6 Yamada-oka, Suita, Osaka (Japan)

    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.

  6. Spectrometer system for diffuse extreme ultraviolet radiation

    Science.gov (United States)

    Labov, Simon E.

    1989-01-01

    A unique grazing incidence spectrometer system has been designed to study diffuse line emission between 80 and 650 A with 10-30 A resolution. The minimum detectable emission line strength during a 5-min observation ranges from 100-2000 ph/sq cm sec str. The instrument uses mechanically ruled reflection gratings placed in front of a linear array of mirrors. These mirrors focus the spectral image on microchannel plate detectors located behind thin filters. The field of view is 40 min of arc by 15 deg, and there is no spatial imaging. This instrument has been fabricated, calibrated, and successfully flown on a sounding rocket to observe the astronomical background radiation.

  7. Further development of a cosmic veto gamma-spectrometer

    International Nuclear Information System (INIS)

    Burnett, J.L.; Davies, A.V.; McLarty, J.L.

    2013-01-01

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a network of certified laboratories that perform high-resolution gamma-spectrometry on global air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of measurements for treaty compliance. The system consists of plastic scintillation plates operated in time-stamp mode to detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer. This provides a mean background reduction of 75.2 % with MDA improvements of 45.6 %. The CTBT requirement for a 140 Ba MDA is achievable after 1.5 days counting compared to 5-7 days using conventional systems. The system does not require dedicated coincidence electronics, and remains easily configurable with dual acquisition of unsuppressed and suppressed spectra. Performance has been significantly improved by complete processing of the cosmic-ray spectrum (0-25 MeV) combined with the Canberra Lynx TM multi-channel analyser. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident. (author)

  8. The impact of normal saline on the incidence of exposure keratopathy in patients hospitalized in intensive care units

    Directory of Open Access Journals (Sweden)

    Zohreh Davoodabady

    2018-01-01

    Full Text Available Background: Patients in the intensive care unit (ICU have impaired ocular protective mechanisms that lead to an increased risk of ocular surface diseases including exposure keratopathy (EK. This study was designed to evaluate the effect of normal saline (NS on the incidence and severity of EK in critically ill patients. Materials and Methods: This single-blind randomized controlled trial was conducted on 50 patients admitted to ICUs. The participants were selected through purposive sampling. One eye of each patient, randomly was allocated to intervention group (standard care with NS and the other eye to control group (standard care. In each patient, one eye (control group randomly received standard care and the other eye (intervention group received NS every 6 h in addition to standard care. The presence and severity of keratopathy was assessed daily until day 7 of hospitalization using fluorescein and an ophthalmoscope with cobalt blue filter. Chi-square test was used for statistical analysis in SPSS software. Results: Before the study ( first day there were no statistically significant differences in the incidence and severity of EK between groups. Although, the incidence and severity of EK after the study (7th day was higher in the intervention group compared to the control group, their differences were not statistically significant. Although, the incidence and severity of EK, from the 1st day until the 7th, increased within both groups, this increase was statistically significant only in the intervention (NS group. Conclusions: The use of NS as eye care in patients hospitalized in ICUs can increase the incidence and severity of EK and is not recommended.

  9. Associated Particle Tagging (APT) in Magnetic Spectrometers

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-10-16

    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.

  10. Diffuse Reflectance Spectroscopy of Human Skin Using a Commercial Fiber Optic Spectrometer

    International Nuclear Information System (INIS)

    Atencio, J. A. Delgado; Rodriguez, M. Cunill; Montiel, S. Vazquez y; Castro, Jorge; Rodriguez, A. Cornejo; Gutierrez, J. L.; Martinez, F.; Gutierrez, B.; Orozco, E.

    2008-01-01

    Diffuse reflectance spectroscopy is a reliable and easy to implement technique in human tissue characterization. In this work we evaluate the performance of the commercial USB4000 miniature fiber optic spectrometer in the in-vivo measurement of the diffuse reflectance spectra of different healthy skin sites and lesions in a population of 54 volunteers. Results show, that this spectrometer reproduces well the typical signatures of skin spectra over the 400-1000 nm region. Remarkable spectral differences exist between lesions and normal surrounding skin. A diffusion-based model was used to simulate reflectance spectra collected by the optical probe of the system

  11. Natures and incidences of each normal variations on I.V.P. series of 1000 Korean females

    International Nuclear Information System (INIS)

    Shin, Ok Ja; Chin, Soo Yil

    1980-01-01

    Each organ of body has many normal variation and/or abnormal developments from fetus to adult, especially urogenital system is very complex and markedly abnormal. The authors attempt to analyze the natures, incidences and differences of each normal variations based on I.V.P. series of 1000 Korean females and the review of literatures were carried out. The results are as follows: 1. The normal variations of urinary tracts are about 30 kinds as follows; Aphasia 0/1000 (0%), Hypoplasia 4/1000 (0.4%), Atrophic kidney 0/1000 (0%), Hyperplasia 0/1000 (0%), Hypertrophied kidney 0/1000 (0%), Supernumerary kidney 0/1000 (0%), Pelvic kidney 0/1000 (0%), Wandering kidney 7/1000 (7%), Horseshoe kidney 2/1000 (2%), Nephroptosis 6/1000 (0.6%), Malroated kidney 0/1000 (0%), Crossed ecotopic kidney 0/1000 (0%), Ureteral kingking 440/1000 (44.0%), Short ureter 3/1000 (0.3%), Long ureter 49/1000 (4.9%), Retrocaval ureter 0/1000 (0%), Retroiliac ureter 0/1000 (0%), Mega-ureter 0/1000 (0%), Aberrant vessel in ureter 79/1000 (7.9%), Congenital ureteral valves 0/1000 (0%), Anomalous ureteral orifices 0/1000 (0%), Double ureter 22/1000 (2.2%), Ureteral diverticulum 0/1000 (0%), Extrarenal pelvis 170/1000 (17.0%), Intrarenal pelvis 830/1000 (83.0%), Supernumerary pelvis 55/1000 (55%), Renal backflow 2/1000 0.2%), Multiple calyces 0/1000 (0.1%), Calyceal diverticulum 2/1000 (0.2%), Unilateral fused kidney 0/1000 (0%), Polar enlarged kidney 0/1000 (0%). 2. The order of incidence of common variations in Korean females are as follows: 1. Intrarenal pelvis 2. Ureteral kingking 3. Extrarenal pelvis 4. Aberrant vessel in ureter 5. Double pelvis 6. Long ureter 7. Double ureter 8. Wandering Kidney 9. Nephrotosis 10. Hypoplasia 11. Short ureter 12. Horseshoe kidney 13. Renal backflow 14. Calyceal diverticulum 15. Supernumerary calyces. 3. The most common variations in Korean females are intrarenal pelvis, extrarenal pelvis, aberrant vessel in ureters and most of them are acquired origin. Contrary

  12. 3m Vacuum Ultraviolet Spectrometer with Optical Multichannel Detector; Espectrometro de ultravioleta de vacio de 3m provisto de sistema de deteccion optical multicanal

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P; Peraza, C; Blanco, F; Campos, J

    1993-07-01

    This paper describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT. It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate / phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the array is digitized by a 12-bit analog to digital converter and stored in a computer, for its later analysis. The necessary software to store and display data has been developed. (Author) 18 refs.

  13. The Dubna double-arm time-of-flight spectrometer for heavy-ion reaction products

    International Nuclear Information System (INIS)

    Schilling, K.D.; Gippner, P.; Seidel, W.; Stary, F.; Will, E.; Heidel, K.; Lukyanov, S.M.; Penionzhkevich, Yu.E.; Salamatin, V.S.; Sodan, H.; Chubarian, G.G.

    1986-05-01

    The double-arm time-of-flight spectrometer DEMAS designed for the detection and identification of heavy-ion reaction products at incident energies below 10 MeV/amu is presented. Based on the kinematic coincidence method, the relevant physical information is obtained from the measurement of the two correlated velocity vectors of the binary fragments. Construction and performance of the different detector systems applied to measure the time-of-flight values, the position coordinates and the kinetic energies of both fragments are presented in detail. The description of the data acquisition and analysing procedures is followed by the discussion of some experimental examples to demonstrate the spectrometer performance. A mass resolution of typically 4 - 5 amu (fwhm) is routinely achieved. (author)

  14. The SAGE spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Pakarinen, J.; Papadakis, P. [University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Sorri, J.; Greenlees, P.T.; Jones, P.; Julin, R.; Konki, J.; Rahkila, P.; Sandzelius, M. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Herzberg, R.D.; Butler, P.A.; Cox, D.M.; Cresswell, J.R.; Mistry, A.; Page, R.D.; Parr, E.; Sampson, J.; Seddon, D.A.; Thornhill, J.; Wells, D. [University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); Coleman-Smith, P.J.; Lazarus, I.H.; Letts, S.C.; Pucknell, V.F.E.; Simpson, J. [STFC Daresbury Laboratory, Warrington (United Kingdom)

    2014-03-15

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

  15. The SAGE spectrometer

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  16. The University of Colorado OSO-8 spectrometer experiment. I - Introduction and optical design considerations

    Science.gov (United States)

    Bruner, E. C., Jr.

    1977-01-01

    The optical design of the high-resolution ultraviolet spectrometer prepared for the OSO-8 spacecraft is discussed. The instrument is a conventional 1 m Ebert-Fastie spectrometer fed by a Cassegrainian telescope. The instrument operates in the spectral range 1200-2000 A with spectral resolution of order 0.02 A. Spatial resolution is about 2.5 arcsec normal to the direction of the slit and is selectable from about 3 arcsec to 15 arcmin along the direction of the slit. Time resolution for the single spectrometer channel is selectable according to the needs of an individual observation and is limited to a maximum sampling rate of 40 ms per data point. The instrument is controlled by an internal general purpose computer.

  17. Choppers to optimise the repetition rate multiplication technique on a direct geometry neutron chopper spectrometer

    International Nuclear Information System (INIS)

    Vickery, A.; Deen, P. P.

    2014-01-01

    In recent years the use of repetition rate multiplication (RRM) on direct geometry neutron spectrometers has been established and is the common mode of operation on a growing number of instruments. However, the chopper configurations are not ideally optimised for RRM with a resultant 100 fold flux difference across a broad wavelength band. This paper presents chopper configurations that will produce a relative constant (RC) energy resolution and a relative variable (RV) energy resolution for optimised use of RRM. The RC configuration provides an almost uniform ΔE/E for all incident wavelengths and enables an efficient use of time as the entire dynamic range is probed with equivalent statistics, ideal for single shot measurements of transient phenomena. The RV energy configuration provides an almost uniform opening time at the sample for all incident wavelengths with three orders of magnitude in time resolution probed for a single European Spallation Source (ESS) period, which is ideal to probe complex relaxational behaviour. These two chopper configurations have been simulated for the Versatile Optimal Resolution direct geometry spectrometer, VOR, that will be built at ESS

  18. Reflection and transmission of normally incident full-vector X waves on planar interfaces

    KAUST Repository

    Salem, Mohamed

    2011-12-23

    The reflection and transmission of full-vector X waves normally incident on planar half-spaces and slabs are studied. For this purpose, X waves are expanded in terms of weighted vector Bessel beams; this new decomposition and reconstruction method offers a more lucid and intuitive interpretation of the physical phenomena observed upon the reflection or transmission of X waves when compared to the conventional plane-wave decomposition technique. Using the Bessel beam expansion approach, we have characterized changes in the field shape and the intensity distribution of the transmitted and reflected full-vector X waves. We have also identified a novel longitudinal shift, which is observed when a full-vector X wave is transmitted through a dielectric slab under frustrated total reflection condition. The results of our studies presented here are valuable in understanding the behavior of full-vector X waves when they are utilized in practical applications in electromagnetics, optics, and photonics, such as trap and tweezer setups, optical lithography, and immaterial probing. © 2011 Optical Society of America.

  19. HELIOS: A high intensity chopper spectrometer at LANSCE

    International Nuclear Information System (INIS)

    Mason, T.E.; Broholm, C.; Fultz, B.

    1998-01-01

    A proposal to construct a high intensity chopper spectrometer at LANSCE as part of the SPSS upgrade project is discussed. HELIOS will be optimized for science requiring high sensitivity neutron spectroscopy. This includes studies of phonon density of states in small polycrystalline samples, magnetic excitations in quantum magnets and highly correlated electron systems, as well as parametric studies (as a function of pressure, temperature, or magnetic field) of S(Q,ω). By employing a compact design together with the use of supermirror guide in the incident flight path the neutron flux at HELIOS will be significantly higher than any other comparable instrument now operating

  20. HELIOS: A high intensity chopper spectrometer at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Mason, T.E. [Oak Ridge National Lab., TN (United States); Broholm, C. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy; Fultz, B. [California Inst. of Tech., Pasadena, CA (United States). Dept. of Materials Science] [and others

    1998-12-31

    A proposal to construct a high intensity chopper spectrometer at LANSCE as part of the SPSS upgrade project is discussed. HELIOS will be optimized for science requiring high sensitivity neutron spectroscopy. This includes studies of phonon density of states in small polycrystalline samples, magnetic excitations in quantum magnets and highly correlated electron systems, as well as parametric studies (as a function of pressure, temperature, or magnetic field) of S(Q,{omega}). By employing a compact design together with the use of supermirror guide in the incident flight path the neutron flux at HELIOS will be significantly higher than any other comparable instrument now operating.

  1. The Omicron Spectrometer

    CERN Document Server

    Allardyce, B W

    1976-01-01

    It is intended to build a spectrometer with a large solid angle and a large momentum acceptance at the reconstructed synchrocyclotron at CERN. This spectrometer will have an energy resolution of about 1 MeV for particles with momenta up to about 400 MeV/c.

  2. The development of a completely automated oxygen isotope mass spectrometer

    International Nuclear Information System (INIS)

    Ahern, T.K.

    1980-01-01

    A completely automated mass spectrometer system has been developed to measure the oxygen isotope ratio of carbon dioxide samples. The system has an accuracy of 0.03 percent, and is capable of analyzing more than 100 samples a day. The system uses an Interdata minicomputer as the primary controller. The intelligence of the system is contained within hardware circuits, software within the minicomputer, and firmware written for a Motorola 6802 microprocessor. A microprocessor-based inlet system controller maximizes the throughput of carbon dioxide samples within the inlet system. The inlet system normally contains four different aliquots of carbon dioxide and introduces these samples to the mass spectrometer through a single admittance leak. The system has been used in the analysis of 111 samples of ice taken from the Steele glacier

  3. Studies of porphyrin-containing specimens using an optical spectrometer connected to a confocal scanning laser microscope.

    Science.gov (United States)

    Trepte, O; Rokahr, I; Andersson-Engels, S; Carlsson, K

    1994-12-01

    A spectrometer has been developed for use with a confocal scanning laser microscope. With this unit, spectral information from a single point or a user-defined region within the microscope specimen can be recorded. A glass prism is used to disperse the spectral components of the recorded light over a linear CCD photodiode array with 256 elements. A regulated cooling unit keeps the detector at 277 K, thereby allowing integration times of up to 60 s. The spectral resolving power, lambda/delta lambda, ranges from 350 at lambda = 400 nm to 100 at lambda = 700 nm. Since the entrance aperture of the spectrometer has the same size as the detector pinhole used during normal confocal scanning, the three-dimensional spatial resolution is equivalent to that of normal confocal scanning. Light from the specimen is deflected to the spectrometer by a solenoid controlled mirror, allowing fast and easy switching between normal confocal scanning and spectrometer readings. With this equipment, studies of rodent liver specimens containing porphyrins have been made. The subcellular localization is of interest for the mechanisms of photodynamic therapy (PDT) of malignant tumours. Spectroscopic detection is necessary to distinguish the porphyrin signal from other fluorescent components in the specimen. Two different substances were administered to the tissue, Photofrin, a haematoporphyrin derivative (HPD) and delta-amino levulinic acid (ALA), a precursor to protoporphyrin IX and haem in the haem cycle. Both are substances under clinical trials for PDT of malignant tumours. Following administration of these compounds to the tissue, the potent photosensitizer and fluorescent compound Photofrin, or protoporphyrin IX, respectively, is accumulated.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Design of a wideband multilayer grating spectrometer for the study of electronic structure of thin-film CIS solar cells

    International Nuclear Information System (INIS)

    Imazono, Takashi; Koike, Masato; Kuramoto, Satoshi; Nagano, Tetsuya; Koeda, Masaru; Moriya, Naoji

    2014-01-01

    A soft x-ray emission spectrometer equipped with a wideband Ni/C multilayer-coated laminar-type varied-line-spacing holographic grating is designed to analyze the electronic structure in thin-film copper indium selenide (CIS) solar cells nondestructively by soft x-ray emission spectroscopy. The spectrometer equipped with the multilayer grating thus designed allows us to detect the L emission lines of Cu, In, and Se simultaneously from a CIS absorber layer in the 1–3.5 keV range at a constant angle of incidence. (author)

  5. A gamma scintillation spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Symbalisty, S

    1952-07-01

    A scintillation type gamma ray spectrometer employing coincidence counting, designed and built at the Physics Department of the University of Western Ontario is described. The spectrometer is composed of two anthracene and photomultiplier radiation detectors, two pulse analyzing channels, a coincidence stage, three scalers and a high voltage stabilized supply. A preliminary experiment to test the operation of the spectrometer was performed and the results of this test are presented. (author)

  6. Incidence and Antimicrobial Sensitivity Profiles of Normal Conjunctiva Bacterial Flora in the Central Area of China: A Hospital-Based Study

    Directory of Open Access Journals (Sweden)

    Hua Tao

    2017-05-01

    Full Text Available Objective: To study the distribution and patterns of resistance to antimicrobial agents of normal conjunctival bacteria.Materials and Methods: Conjunctival specimens were collected from 8,224 patients and then cultured, which underwent antimicrobial susceptibility test following standard methods. Patients with infectious symptoms such as erythema or oedema and those using systemic or topical antibiotics within 1 month were excluded.Results: In this study, the incidence of isolated bacteria was 24.2%. The middle aged group of 41–65 years presented the lowest rate of bacterial isolation which was 19.4%, while the highest isolation rate (83.1% was found in patients in the age range of 0–6 years. In every age group, the incidence of bacterial isolation in men was higher than that in women. The top 3 most commonly isolated micro-organisms were Staphylococcus epidermidis (39.7%, Streptococcus pneumoniae (4.5%, and Staphylococcus aureus (2.7%, of which about 83.1% S. aureus were isolated in the group of 0-6 years. We found that coagulase-negative Staphylococcus (CONS were more resistant to penicillin, macrolides, clindamycin and sulfonamides with the rate ranging from 57.9 to 90.8%, which were highly susceptible to vancomycin, linezolid, rifampin, tetracyclines, and aminoglycosides. Contrasting to CONS, the general resistance rate of S. aureus was significantly lower. Additionally, Streptococcus was susceptible well to the majority of antimicrobial agents, while highly resistant to macrolides and tetracyclines with the rate >80%.Conclusions: In conclusion, our study revealed the incidence and antimicrobial sensitivity profiles of normal conjunctiva bacterial flora in the central area of China, which could be useful in the prevention of ocular infections. Importantly, our data could be used to guide the selection of appropriate prophylactic agents.

  7. Amyloid burden and incident depressive symptoms in cognitively normal older adults.

    Science.gov (United States)

    Harrington, Karra D; Gould, Emma; Lim, Yen Ying; Ames, David; Pietrzak, Robert H; Rembach, Alan; Rainey-Smith, Stephanie; Martins, Ralph N; Salvado, Olivier; Villemagne, Victor L; Rowe, Christopher C; Masters, Colin L; Maruff, Paul

    2017-04-01

    Several studies have reported that non-demented older adults with clinical depression show changes in amyloid-β (Aβ) levels in blood, cerebrospinal fluid and on neuroimaging that are consistent with those observed in patients with Alzheimer's disease. These findings suggest that Aβ may be one of the mechanisms underlying the relation between the two conditions. We sought to determine the relation between elevated cerebral Aβ and the presence of depression across a 54-month prospective observation period. Cognitively normal older adults from the Australian Imaging Biomarkers and Lifestyle study who were not depressed and had undergone a positron emission tomography scan to classify them as either high Aβ (n = 81) or low Aβ (n = 278) participated. Depressive symptoms were assessed using the Geriatric Depression Scale - Short Form at 18-month intervals over 54 months. Whilst there was no difference in probable depression between groups at baseline, incidence was 4.5 (95% confidence interval [CI] 1.3-16.4) times greater within the high Aβ group (9%) than the low Aβ group (2%) by the 54-month assessment. Results of this study suggest that elevated Aβ levels are associated with a 4.5-fold increased likelihood of developing clinically significant depressive symptoms on follow-up in preclinical Alzheimer's disease. This underscores the importance of assessing, monitoring and treating depressive symptoms in older adults with elevated Aβ. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Acquisition of HPLC-Mass Spectrometer

    Science.gov (United States)

    2015-08-18

    31-Jan-2015 Approved for Public Release; Distribution Unlimited Final Report: Acquisition of HPLC -Mass Spectrometer The views, opinions and/or findings...published in peer-reviewed journals: Final Report: Acquisition of HPLC -Mass Spectrometer Report Title The acquisition of the mass spectrometer has been a

  9. The multiple disk chopper neutron time-of-flight spectrometer at NIST

    International Nuclear Information System (INIS)

    Altorfer, F.B.; Cook, J.C.; Copley, J.R.D.

    1995-01-01

    A highly versatile multiple disk chopper neutron time-of-flight spectrometer is being installed at the Cold Neutron Research Facility of the National institute of Standards and Technology. This new instrument will fill an important gap in the portfolio of neutron inelastic scattering spectrometers in North America. It will be used for a wide variety of experiments such as studies of magnetic and vibrational excitations, tunneling spectroscopy, and quasielastic neutron scattering investigations of local and translational diffusion. The instrument uses disk choppers to monochromate and pulse the incident beam, and the energy changes of scattered neutrons are determined from their times-of-flight to a large array of detectors. The disks and the guide have been designed to make the instrument readily adaptable to the specific performance requirements of experimenters. The authors present important aspects of the design, as well as estimated values of the flux at the sample and the energy resolution for elastic scattering. The instrument should be operational in 1996

  10. Fourier Transform Spectrometer System

    Science.gov (United States)

    Campbell, Joel F. (Inventor)

    2014-01-01

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

  11. A compact CMA spectrometer with axially integrated hybrid electron-ion gun for ISS, AES and sputter depth profile analysis

    International Nuclear Information System (INIS)

    Gisler, E.; Bas, E.B.

    1986-01-01

    Until now, the combined application of electrons and ions in surface analysis required two separate sources for electrons and ions with different incidence angles. The newly developed hybrid electron-ion gun, however, allows bombardment of the same sample area both with noble gas ions and with electrons coming from the same direction. By integrating such a hybrid gun axially in a cylindrical mirror energy analyser (CMA) a sensitive compact single flange spectrometer obtains for ion scattering spectroscopy (ISS), Auger electron spectroscopy (AES), and sputtering all within normal beam incidence. This concept makes accurate beam centering very easy. Additionally, the bombardment from the same direction both for sputtering and for surface analysis brings advantages in depth profiling. The scattering angle for ISS has a constant value of about 138 0 . The hybrid gun delivers typically an electron beam current of -20μA at 3keV for AES, and an ion beam current of +40 nA and +1.2μA at 2 keV for ISS and sputtering respectively. The switching time between ISS, AES, and sputtering mode is about 0.1 s. So this system is best suited for automatically controlled depth profile analysis. The design and operation of this new system will be described and some applications will be discussed. (author)

  12. The Wavelength-Dispersive Spectrometer and Its Proposed Use in the Analytical Electron Microscope

    Science.gov (United States)

    Goldstein, Joseph I.; Lyman, Charles E.; Williams, David B.

    1989-01-01

    The Analytical Electron Microscope (AEM) equipped with a wavelength-dispersive spectrometer (WDS) should have the ability to resolve peaks which normally overlap in the spectra from an energy-dispersive spectrometer (EDS). With a WDS it should also be possible to measure lower concentrations of elements in thin foils due to the increased peak-to-background ratio compared with EDS. The WDS will measure X-ray from the light elements (4 less than Z less than 1O) more effectively. This paper addresses the possibility of interfacing a compact WDS with a focussing circle of approximately 4 cm to a modem AEM with a high-brightness (field emission) source of electrons.

  13. Results from a prototype chicane-based energy spectrometer for a linear collider

    Energy Technology Data Exchange (ETDEWEB)

    Lyapin, A. [Univ. College London (United Kingdom); London Univ., Egham (United Kingdom). Royal Holloway; Schreiber, H.J.; Viti, M. [Deutsches Electronen Synchrotron DESY, Hamburg (Germany); Deutsches Electronen Synchrotron DESY, Zeuthen (DE)] (and others)

    2010-11-15

    The International Linear Collider (ILC) and other proposed high energy e{sup +}e{sup -} machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 10{sup -4}. This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006-2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5 . 10{sup -4} was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance. (orig.)

  14. Digital positron annihilation spectrometer

    International Nuclear Information System (INIS)

    Cheng Bin; Weng Huimin; Han Rongdian; Ye Bangjiao

    2010-01-01

    With the high speed development of digital signal process, the technique of the digitization and processing of signals was applied in the domain of a broad class of nuclear technique. The development of digital positron lifetime spectrometer (DPLS) is more promising than the conventional positron lifetime spectrometer equipped with nuclear instrument modules. And digital lifetime spectrometer has many advantages, such as low noise, long term stability, flexible online or offline digital processing, simple setup, low expense, easy to setting, and more physical information. Digital constant fraction discrimination is for timing. And a new method of optimizing energy windows setting for digital positron lifetime spectrometer is also developed employing the simulated annealing for the convenient use. The time resolution is 220ps and the count rate is 200cps. (authors)

  15. Automatic control unit for A neutron diffraction crystal spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Adib, M.; Abbas, Y.; Mostafa, M.; Hamouda, I.

    1982-01-01

    An automatic transistorized unit has been designed and constructed to control the operation of the double axis crystal spectrometer installed in front of one of the horizontal channels of the ET-RR-1 reactor. The function of the automatic unit is to store the diffracted neutrons at a certain angle with respect to the direction of the incident neutron beam in a selected channel of a 1024-multichannel analyzer for a certain preadjusted time period. AT the end of this time period the unit rotates the spectrometer's arm to another angle, selects the next channel of the MCA and provides the measurement of the diffracted neutron for the same time period. Such a sequence is repeated automatically over all angles required for the neutron diffraction pattern of the sample under investigation. As a result, the stored information at the MCA provides the neutron diffraction pattern as a function of channel number, where each channel corresponds to a certain scattering angle. The stored distribution at MCA can be obtained through the analyzer read out unit. The designed automatic unit has the possibility of providing the neutron diffraction pattern using a 6-digit scaler and a printer.

  16. First results from PHAROS, the new chopper spectrometer at LANSCE

    International Nuclear Information System (INIS)

    Olivier, B.J.; Sandoval, J.P.; Lysaght, P.; Nutter, M.; Robinson, R.A.

    1993-01-01

    In this article we present the first experimental measurements obtained on PHAROS during the 1992 run cycle at LANSCE. These are data on the phasing of the choppers relative to the accelerator system along with the consequent neutronic resolution, data on the real-space position resolution of the main detectors, a white-beam nickel powder calibration, and our first inelastic scattering measurement made on TiH 2 with an incident energy of 300 MeV. The characteristic features of the new chopper spectrometer PHAROS, designed for low-angle inelastic neutron scattering and neutron Brillouin scattering, are described elsewhere in these proceedings

  17. Absolute sensitivity calibration from 20 A to 430 A of a grazing incidence spectrometer with a multi-element spectral detector

    International Nuclear Information System (INIS)

    Terry, J.L.; Manning, H.L.; Marmar, E.S.

    1986-07-01

    Two methods which together allow sensitivity calibration from 20 A to 430 A are described in detail. The first method, useful up to 120 A, uses a low power source to generate Kα x-rays which are alternately viewed by an absolute detector (a proportional counter) and the spectrometer. The second method extends that calibration to 430 A. It relies on the 2:1 brightness ratio of bright doublet lines from impurity ions which have a single outer shell electron and which are present in hot, magnetically confined plasmas. It requires that the absolute sensitivity of the spectrometer be known at one wavelength point, and in practice requires a multi-element spectral detector

  18. Evaluation of moving-coil loudspeaker and passive radiator parameters using normal-incidence sound transmission measurements: theoretical developments.

    Science.gov (United States)

    Leishman, Timothy W; Anderson, Brian E

    2013-07-01

    The parameters of moving-coil loudspeaker drivers are typically determined using direct electrical excitation and measurement. However, as electro-mechano-acoustical devices, their parameters should also follow from suitable mechanical or acoustical evaluations. This paper presents the theory of an acoustical method of excitation and measurement using normal-incidence sound transmission through a baffled driver as a plane-wave tube partition. Analogous circuits enable key parameters to be extracted from measurement results in terms of open and closed-circuit driver conditions. Associated tools are presented that facilitate adjacent field decompositions and derivations of sound transmission coefficients (in terms of driver parameters) directly from the circuits. The paper also clarifies the impact of nonanechoic receiving tube terminations and the specific benefits of downstream field decompositions.

  19. A novel electrostatic ion-energy spectrometer by the use of a proposed ``self-collection'' method for secondary-electron emission from a metal collector

    Science.gov (United States)

    Hirata, M.; Nagashima, S.; Cho, T.; Kohagura, J.; Yoshida, M.; Ito, H.; Numakura, T.; Minami, R.; Kondoh, T.; Nakashima, Y.; Yatsu, K.; Miyoshi, S.

    2003-03-01

    For the purpose of end-loss-ion energy analyses in open-field plasmas, a newly developed electrostatic ion-energy spectrometer is proposed on the basis of a "self-collection" principle for secondary-electron emission from a metal collector. The ion-energy spectrometer is designed with multiple grids for analyzing incident ion energies, and a set of parallelly placed metal plates with respect to lines of ambient magnetic forces in an open-ended device. One of the most important characteristic properties of this spectrometer is the use of our proposed principle of a "self-collection" mechanism due to E×B drifts for secondary electrons emitted from the grounded metal-plate collector by the use of no further additional magnetic systems except the ambient open-ended fields B. The proof-of-principle and characterization experiments are carried out by the use of a test-ion-beam line along with an additional use of a Helmholtz coil system for the formation of open magnetic fields similar to those in the GAMMA 10 end region. The applications of the developed ion-energy spectrometer for end-loss-ion diagnostics in the GAMMA 10 plasma experiments are demonstrated under the conditions with simultaneous incidence of energetic electrons produced by electron-cyclotron heatings for end-loss-plugging potential formation, since these electrons have contributed to disturb these ion signals from conventional end-loss-ion detectors.

  20. Interfacing of home-made photoacoustic spectrometer to computer

    International Nuclear Information System (INIS)

    Dhobale, A.R.; Chaturvedi, T.P.; Venkiteswaran, S.; Sastry, M.D.

    1996-01-01

    This report describes the interfacing of Photo Acoustic Spectrometer (PAS) fabricated in-house to a personal computer. This work was carried out to make a state of the art computer based spectrometer with provision for automatic background correction and also which gives hard copy of the spectrum. This report includes the development of software necessary to acquire data and for further processing of the signal. The monochromator used was modified for obtaining a +5 V pulse for each wavelength position. This pulse was further used for controlling the data acquisition and automatic increment of wavelength. Software program was developed in Quick Basic ver. 4.5 environment for acquisition, storage, display and analysis of the spectrum. The program displays on-line spectrum building up on the monitor. Another program converts the acquired spectrum into a normalized spectrum comparing with carbon spectrum stored already in addition to the S/N ratio improvement. The photo acoustic cell and chopper unit were also modified for improving the performance of the PAS unit. (author). 11 refs., 13 figs., 2 tabs

  1. Simulation of the SAGE spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Cox, D.M.; Herzberg, R.D. [University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); Konki, J.; Greenlees, P.T.; Pakarinen, J.; Papadakis, P.; Rahkila, P.; Sandzelius, M.; Sorri, J. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Hauschild, K. [Universite Paris-Sud, CSNSM-IN2P3-CNRS, Orsay (France)

    2015-06-15

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

  2. Simulation of the SAGE spectrometer

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  3. A beta ray spectrometer based on a two-, or three-element silicon detector coincidence telescope

    International Nuclear Information System (INIS)

    Horowitz, Y.S.; Weizman, Y.; Hirning, C.R.

    1995-01-01

    The operation of a beta ray energy spectrometer based on a two-or three-element silicon detector telescope is described. The front detector (A) is a thin, totally depleted, silicon surface barrier detector either 40 μm, 72 μm or 98 μm thick. The back detector (C) is a Li compensated silicon detector, 5000 μm thick. An additional thin detector can be inserted between these two detectors when additional photon rejection capability is required in intense photon fields. The capability of the spectrometer to reject photons is based on the fact that incident photons will have a small probability of simultaneously losing detectable energy in two detectors and an even smaller probability of losing detectable energy in all three detectors. Electrons, however, above a low energy threshold, will always record simultaneous, events in all three detectors. The spectrometer is capable of measuring electron energies from a lower energy coincidence threshold of 70 keV with 60% efficiency increasing to 100% efficiency in the energy region between 150 keV and 2.5 MeV. (Author)

  4. Cryogenic Scan Mechanism for Fourier Transform Spectrometer

    Science.gov (United States)

    Brasunas, John C.; Francis, John L.

    2011-01-01

    A compact and lightweight mechanism has been developed to accurately move a Fourier transform spectrometer (FTS) scan mirror (a cube corner) in a near-linear fashion with near constant speed at cryogenic temperatures. This innovation includes a slide mechanism to restrict motion to one dimension, an actuator to drive the motion, and a linear velocity transducer (LVT) to measure the speed. The cube corner mirror is double-passed in one arm of the FTS; double-passing is required to compensate for optical beam shear resulting from tilting of the moving cube corner. The slide, actuator, and LVT are off-the-shelf components that are capable of cryogenic vacuum operation. The actuator drives the slide for the required travel of 2.5 cm. The LVT measures translation speed. A proportional feedback loop compares the LVT voltage with the set voltage (speed) to derive an error signal to drive the actuator and achieve near constant speed. When the end of the scan is reached, a personal computer reverses the set voltage. The actuator and LVT have no moving parts in contact, and have magnetic properties consistent with cryogenic operation. The unlubricated slide restricts motion to linear travel, using crossed roller bearings consistent with 100-million- stroke operation. The mechanism tilts several arc seconds during transport of the FTS mirror, which would compromise optical fringe efficiency when using a flat mirror. Consequently, a cube corner mirror is used, which converts a tilt into a shear. The sheared beam strikes (at normal incidence) a flat mirror at the end of the FTS arm with the moving mechanism, thereby returning upon itself and compensating for the shear

  5. The change in color matches with retinal angle of incidence of the colorimeter beams.

    Science.gov (United States)

    Alpern, M; Kitahara, H; Fielder, G H

    1987-01-01

    Differences between W.D.W. chromaticities of monochromatic lights obtained with all colorimeter beams incident on the retina "off-axis" and those found for lights striking the retina normally have been studied throughout the visible spectrum on 4 normal trichromats. The results are inconsistent with: (i) the assumption in Weale's theories of the Stiles-Crawford hue shift that the sets of absorption spectra of the visual pigments catching normally and obliquely incident photons are identical, and (ii) "self-screening" explanations for the change in color with angle of incidence on the retina. The color matching functions of a protanomalous trichromat are inconsistent with the hypothesis that the absorption spectra of the visual pigments catching normally incident photons in his retina are those catching obliquely incident photons in the normal retina.

  6. The MEG positron spectrometer

    International Nuclear Information System (INIS)

    Nishiguchi, Hajime

    2007-01-01

    We have been developing an innovative spectrometer for the MEG experiment at the Paul Scherrer Institute (PSI) in Switzerland. This experiment searches for a lepton flavour violating decay μ + →e + γ with a sensitivity of 10 -13 in order to explore the region predicted by supersymmetric extensions of the standard model. The MEG positron spectrometer consists of a specially designed superconducting solenoidal magnet with a highly graded field, an ultimate low-mass drift chamber system, and a precise time measuring counter system. This innovative positron spectrometer is described here focusing on the drift chamber system

  7. VEGAS: VErsatile GBT Astronomical Spectrometer

    Science.gov (United States)

    Bussa, Srikanth; VEGAS Development Team

    2012-01-01

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

  8. A dual purpose Compton suppression spectrometer

    CERN Document Server

    Parus, J; Raab, W; Donohue, D

    2003-01-01

    A gamma-ray spectrometer with a passive and an active shield is described. It consists of a HPGe coaxial detector of 42% efficiency and 4 NaI(Tl) detectors. The energy output pulses of the Ge detector are delivered into the 3 spectrometry chains giving the normal, anti- and coincidence spectra. From the spectra of a number of sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co sources a Compton suppression factor, SF and a Compton reduction factor, RF, as the parameters characterizing the system performance, were calculated as a function of energy and source activity and compared with those given in literature. The natural background is reduced about 8 times in the anticoincidence mode of operation, compared to the normal spectrum which results in decreasing the detection limits for non-coincident gamma-rays up to a factor of 3. In the presence of other gamma-ray activities, in the range from 5 to 11 kBq, non- and coincident, the detection limits can be decreased for some nuclides by a factor of 3 to 5.7.

  9. Magnetic spectrometer Grand Raiden

    International Nuclear Information System (INIS)

    Fujiwara, M.; Akimune, H.; Daito, I.; Fujimura, H.; Fujita, Y.; Hatanaka, K.; Ikegami, H.; Katayama, I.; Nagayama, K.; Matsuoka, N.; Morinobu, S.; Noro, T.; Yoshimura, M.; Sakaguchi, H.; Sakemi, Y.; Tamii, A.; Yosoi, M.

    1999-01-01

    A high-resolution magnetic spectrometer called 'Grand Raiden' is operated at the RCNP ring cyclotron facility in Osaka for nuclear physics studies at intermediate energies. This magnetic spectrometer has excellent ion-optical properties. In the design of the spectrometer, the second-order dispersion matching condition has been taken into account, and almost all the aberration terms such as (x vertical bar θ 3 ), (x vertical bar θφ 2 ), (x vertical bar θ 2 δ) and (x vertical bar θδ 2 ) in a third-order matrix calculation are optimized. A large magnetic rigidity of the spectrometer (K = 1400 MeV) gives a great advantage to measure the charge-exchange ( 3 He, t) reactions at 450 MeV. The ability of the high-resolution measurement has been demonstrated. Various coincidence measurements are performed to study the nuclear structures of highly excited states through decay properties of nuclear levels following nuclear reactions at intermediate energies

  10. A large-acceptance Bragg curve spectrometer with a longitudinal electric field and a segmented anode

    International Nuclear Information System (INIS)

    Farrar, K.A.; Hasan, A.T.; Prosser, F.W.; Sanders, S.J.; Henderson, D.J.

    1994-01-01

    A large-acceptance Bragg curve spectrometer with a longitudinal electron collection field and a segmented anode has been constructed and tested. The effects on the charge resolution of the entrance angle and entrance position of the incident particle have been studied. Simulations have been done in order to isolate the contribution to the overall detector performance of the signal-shaping electronics from that of the intrinsic design of the detector. ((orig.))

  11. RITA-type triple axis spectrometers

    International Nuclear Information System (INIS)

    Roennow, H.M.

    2001-01-01

    The RITA spectrometer at Risoe National Laboratory was the first to incorporate a complete re-thinking of the neutron-path from source, through detector to analysis. Since then, other RITA-type spectrometers such as SPINS at NIST, RITA-II at PSI have been built, and several new spectrometers around the world are adapting the same philosophy. The main novelty of RITA was the introduction of a single back-end tank featuring both an analyser block with multiple individually turnable analyser blades and a 2D position sensitive detector. Several new triple-axis spectrometers are presently being built at existing and future sources, and almost all of them have learnt from the experience with RITA. (R.P.)

  12. Normal Incidence of Sound Transmission Loss of a Double-Leaf Partition Inserted with a Microperforated Panel

    Directory of Open Access Journals (Sweden)

    A. Putra

    2013-01-01

    Full Text Available A double-leaf partition in engineering structures has been widely applied for its advantages, that is, in terms of its mechanical strength as well as its lightweight property. In noise control, the double-leaf also serves as an effective noise barrier. Unfortunately at low frequency, the sound transmission loss reduces significantly due to the coupling between the panels and the air between them. This paper studies the effect of a microperforated panel (MPP inserted inside a double-leaf partition on the sound transmission loss performance of the system. The MPP insertion is proposed to provide a hygienic double-leaf noise insulator replacing the classical abrasive porous materials between the panels. It is found that the transmission loss improves at the troublesome mass-air-mass resonant frequency if the MPP is located closer to the solid panel. The mathematical model is derived for normal incidence of acoustic loading.

  13. Software for mass spectrometer control

    International Nuclear Information System (INIS)

    Curuia, Marian; Culcer, Mihai; Anghel, Mihai; Iliescu, Mariana; Trancota, Dan; Kaucsar, Martin; Oprea, Cristiana

    2004-01-01

    The paper describes a software application for the MAT 250 mass spectrometer control, which was refurbished. The spectrometer was bring-up-to-date using a hardware structure on its support where the software application for mass spectrometer control was developed . The software application is composed of dedicated modules that perform given operations. The instructions that these modules have to perform are generated by a principal module. This module makes possible the change of information between the modules that compose the software application. The use of a modal structure is useful for adding new functions in the future. The developed application in our institute made possible the transformation of the mass spectrometer MAT 250 into a device endowed with other new generation tools. (authors)

  14. Mass spectrometers in medicine

    International Nuclear Information System (INIS)

    Bushman, J.A.

    1975-01-01

    This paper describes how the mass spectrometer enables true lung function, namely the exchange of gases between the environment and the organism, to be measured. This has greatly improved the understanding of respiratory disease and the latest generation of respiratory mass spectrometers will do much to increase the application of the technique. (author)

  15. An automatic control unit for A neutron diffraction crystal spectrometer

    International Nuclear Information System (INIS)

    Adib, M.; Abbas, Y.; Mostafa, M.; Hamouda, I.

    1982-01-01

    An automatic transistorized unit has been designed and constructed to control the operation of the double axis crystal spectrometer installed in front of one of the horizontal channels of the ET-RR-1 reactor. The function of the automatic unit is to store the diffracted neutrons at a certain angle with respect to the direction of the incident neutron beam in a selected channel of a 1024-multichannel analyzer for a certain preadjusted time period. AT the end of this time period the unit rotates the spectrometer's arm to another angle, selects the next channel of the MCA and provides the measurement of the diffracted neutron for the same time period. Such a sequence is repeated automatically over all angles required for the neutron diffraction pattern of the sample under investigation. As a result, the stored information at the MCA provides the neutron diffraction pattern as a function of channel number, where each channel corresponds to a certain scattering angle. The stored distribution at MCA can be obtained through the analyzer read out unit. The designed automatic unit has the possibility of providing the neutron diffraction pattern using a 6-digit scaler and a printer

  16. Determination of lifetimes of nuclear excited states using the Recoil Distance Doppler Shift Method in combination with magnetic spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Doncel, M. [Universidad de Salamanca, Laboratorio de Radiaciones Ionizantes, Salamanca (Spain); Royal Institute of Technology, Department of Physics, Stockholm (Sweden); University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); Gadea, A. [CSIC-University of Valencia, Istituto de Fisica Corpuscular, Valencia (Spain); Valiente-Dobon, J.J. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); Quintana, B. [Universidad de Salamanca, Laboratorio de Radiaciones Ionizantes, Salamanca (Spain); Modamio, V. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); University of Oslo, Oslo (Norway); Mengoni, D. [Dipartimento di Fisica e Astronomia, Universita di Padova, Padova (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Moeller, O.; Pietralla, N. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Dewald, A. [Institut fuer Kernphysik, Universitaet Koeln (Germany)

    2017-10-15

    The current work presents the determination of lifetimes of nuclear excited states using the Recoil Distance Doppler Shift Method, in combination with spectrometers for ion identification, normalizing the intensity of the peaks by the ions detected in the spectrometer as a valid technique that produces results comparable to the ones obtained by the conventional shifted-to-unshifted peak ratio method. The technique has been validated using data measured with the γ-ray array AGATA, the PRISMA spectrometer and the Cologne plunger setup. In this paper a test performed with the AGATA-PRISMA setup at LNL and the advantages of this new approach with respect to the conventional Recoil Distance Doppler Shift Method are discussed. (orig.)

  17. spectrometer

    Directory of Open Access Journals (Sweden)

    J. K. Hedelius

    2016-08-01

    Full Text Available Bruker™ EM27/SUN instruments are commercial mobile solar-viewing near-IR spectrometers. They show promise for expanding the global density of atmospheric column measurements of greenhouse gases and are being marketed for such applications. They have been shown to measure the same variations of atmospheric gases within a day as the high-resolution spectrometers of the Total Carbon Column Observing Network (TCCON. However, there is little known about the long-term precision and uncertainty budgets of EM27/SUN measurements. In this study, which includes a comparison of 186 measurement days spanning 11 months, we note that atmospheric variations of Xgas within a single day are well captured by these low-resolution instruments, but over several months, the measurements drift noticeably. We present comparisons between EM27/SUN instruments and the TCCON using GGG as the retrieval algorithm. In addition, we perform several tests to evaluate the robustness of the performance and determine the largest sources of errors from these spectrometers. We include comparisons of XCO2, XCH4, XCO, and XN2O. Specifically we note EM27/SUN biases for January 2015 of 0.03, 0.75, –0.12, and 2.43 % for XCO2, XCH4, XCO, and XN2O respectively, with 1σ running precisions of 0.08 and 0.06 % for XCO2 and XCH4 from measurements in Pasadena. We also identify significant error caused by nonlinear sensitivity when using an extended spectral range detector used to measure CO and N2O.

  18. Results on search for a QGP with a TPC magnetic spectrometer at AGS and plans for an ∼4π TPC magnetic spectrometer at RHIC

    International Nuclear Information System (INIS)

    Lindenbaum, S.J.

    1991-01-01

    In the first part of this paper a search for a Quark-Gluon Plasma (QGP) with a TPC Magnetic Spectrometer at AGS by the BNL/CCNY/Johns Hopkins/Rice (E-810) Collaboration is discussed. At AGS energies the expected increase in baryon density is near maximum. If a QGP is formed even rarely this approach provides a sensitive method for its detection. We have found some interesting phenomena including strangeness enhancement, multi-Λ and K s 0 events and an increased slope for π - (corresponding to a reduced temperature) in the usual temperature plot for p perpendicular < 0.2 GeV/c. We plan to increase the statistics with the 14.5 GeV/c x A Si ions on targets from light to heavy and then to continue the program with incident Au ions. In Part 2 we discuss the BNL/CCNY/Notre Dame/Rice proposal for an ∼ 4π TPC Magnetic Spectrometer for RHIC which we believe will be a sensitive probe for hadronic QGP signals, and also capable of observing departures from QCD should they occur. 8 refs., 12 figs

  19. The feasibility of using a Fourier RTOF spectrometer at a low-power research reactor

    International Nuclear Information System (INIS)

    Maayouf, R.M.A.; Priesmeyer, H.G.; Kudryashev, V.A.

    1991-01-01

    The present situation of Fourier time-of-flight (TOF) spectrometry is discussed using the FSS spectrometer as example. The use of the Fourier reverse TOF spectrometry, as an efficient tool for studying condensed matter, at a 2 MW (WWR-S type) reactor is also assessed. The arrangement of the RTOF spectrometer, which could be successfully used at such type of reactor, is introduced. The suggested arrangement applies a neutron guide tube of 24 m length and allows for effective luminosity 2.4.10 6 at a flight path distance of 3.6 m. The number of neutrons scattered from a sample (5 cm 3 in volume) and incident on the detector system, as estimated for the suggested arrangement, is ∝1.6.10 3 n/sec. Such high counting rate allows to measure a diffraction spectrum within less than an hour. (orig.) With 12 figs [de

  20. J-NSE: Neutron spin echo spectrometer

    Directory of Open Access Journals (Sweden)

    Olaf Holderer

    2015-08-01

    Full Text Available Neutron Spin-Echo (NSE spectroscopy is well known as the only neutron scattering technique that achieves energy resolution of several neV. By using the spin precession of polarized neutrons in magnetic field one can measure tiny velocity changes of the individual neutron during the scattering process. Contrary to other inelastic neutron scattering techniques, NSE measures the intermediate scattering function S(Q,t in reciprocal space and time directly. The Neutron Spin-Echo spectrometer J-NSE, operated by JCNS, Forschungszentrum Jülich at the Heinz Maier-Leibnitz Zentrum (MLZ in Garching, covers a time range (2 ps to 200 ns on length scales accessible by small angle scattering technique. Along with conventional NSE spectroscopy that allows bulk measurements in transmission mode, J-NSE offers a new possibility - gracing incidence spin echo spectroscopy (GINSENS, developed to be used as "push-button" option in order to resolve the depth dependent near surface dynamics.

  1. Efficient mass calibration of magnetic sector mass spectrometers

    International Nuclear Information System (INIS)

    Roddick, J.C.

    1996-01-01

    Magnetic sector mass spectrometers used for automatic acquisition of precise isotopic data are usually controlled with Hall probes and software that uses polynomial equations to define and calibrate the mass-field relations required for mass focusing. This procedure requires a number of reference masses and careful tuning to define and maintain an accurate mass calibration. A simplified equation is presented and applied to several different magnetically controlled mass spectrometers. The equation accounts for nonlinearity in typical Hall probe controlled mass-field relations, reduces calibration to a linear fitting procedure, and is sufficiently accurate to permit calibration over a mass range of 2 to 200 amu with only two defining masses. Procedures developed can quickly correct for normal drift in calibrations and compensate for drift during isotopic analysis over a limited mass range such as a single element. The equation is: Field A·Mass 1/2 + B·(Mass) p where A, B, and p are constants. The power value p has a characteristic value for a Hall probe/controller and is insensitive to changing conditions, thus reducing calibration to a linear regression to determine optimum A and B. (author). 1 ref., 1 tab., 6 figs

  2. Electron spectrometer for gas-phase spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bozek, J.D.; Schlachter, A.S. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

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

  3. Antipp elastic scattering at 30 GeV/c incident momentum

    International Nuclear Information System (INIS)

    Fearnley, T.

    1983-01-01

    The antipp elastic differential cross-section at 30 GeV/c incident momentum has been measured in a two-arm spectrometer experiment (WA7) at the CERN SPS. The /t/-range covered extends from 0.5 to 5.0 (GeV/c) 2 . A pronounced dip-bump structure is observed, with a sharp minimum around /t/=1.7 (GeV/c) 2 . The results are compared to existing antipp data and to some model predictions

  4. Spectrometers for compact neutron sources

    Science.gov (United States)

    Voigt, J.; Böhm, S.; Dabruck, J. P.; Rücker, U.; Gutberlet, T.; Brückel, T.

    2018-03-01

    We discuss the potential for neutron spectrometers at novel accelerator driven compact neutron sources. Such a High Brilliance Source (HBS) relies on low energy nuclear reactions, which enable cryogenic moderators in very close proximity to the target and neutron optics at comparably short distances from the moderator compared to existing sources. While the first effect aims at increasing the phase space density of a moderator, the second allows the extraction of a large phase space volume, which is typically requested for spectrometer applications. We find that competitive spectrometers can be realized if (a) the neutron production rate can be synchronized with the experiment repetition rate and (b) the emission characteristics of the moderator can be matched to the phase space requirements of the experiment. MCNP simulations for protons or deuterons on a Beryllium target with a suitable target/moderator design yield a source brightness, from which we calculate the sample fluxes by phase space considerations for different types of spectrometers. These match closely the figures of todays spectrometers at medium flux sources. Hence we conclude that compact neutron sources might be a viable option for next generation neutron sources.

  5. Lessons learned with the SAGE spectrometer

    International Nuclear Information System (INIS)

    Sorri, J; Greenlees, P T; Jones, P; Julin, R; Konki, J; Pakarinen, J; Rahkila, P; Sandzelius, M; Uusitalo, J; Papadakis, P; Cox, D M; Herzberg, R D

    2012-01-01

    The SAGE spectrometer combines a high-efficiency γ-ray detection system with an electron spectrometer. Some of the design features have been known to be problematic and surprises have come up during the early implementation of the spectrometer. Tests related to bismuth germanate Compton-suppression shields, electron detection efficiency and an improved cooling system are discussed in the paper. (paper)

  6. The performance of TOF near backscattering spectrometer DNA in MLF, J-PARC

    International Nuclear Information System (INIS)

    Shibata, Kaoru; Kawakita, Yukinobu; Kambara, Wataru; Inamura, Yasuhiro; Nakatani, Takeshi; Nakajima, Kenji; Arai, Masatoshi; Takahashi, Nobuaki; Matsuura, Masato; Yamada, Takeshi; Tominaga, Taiki; Kobayashi, Makoto

    2015-01-01

    The time-of-flight (TOF) type near-backscattering spectrometer (n-BSS), DNA, with Si crystal analyzers was built and started operation in 2012 at the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). DNA is the first n-BSS with pulse shaping chopper installed at a spallation pulsed neutron source. It offers currently the highest energy-resolution of about 2.4 micro eV by operating a pulse shaping double-disk chopper at 225 Hz whose phase is optimized to the narrowest slit of 10 mm width. Energy resolution can be flexibly compromised with intensity during experiment by using two type slits with different widths and changing the copper frequency. An example of measurement with high energy-resolution under the condition that the pulse shaping chopper was operated is shown, where the limited measurable energy range was widely expanded by multi incident energy band technique. The experimental data demonstrate extremely high signal-to-noise ratio (∼10"5) of this spectrometer. (author)

  7. High resolution solar soft X-ray spectrometer

    International Nuclear Information System (INIS)

    Zhang Fei; Wang Huanyu; Peng Wenxi; Liang Xiaohua; Zhang Chunlei; Cao Xuelei; Jiang Weichun; Zhang Jiayu; Cui Xingzhu

    2012-01-01

    A high resolution solar soft X-ray spectrometer (SOX) payload onboard a satellite is developed. A silicon drift detector (SDD) is adopted as the detector of the SOX spectrometer. The spectrometer consists of the detectors and their readout electronics, a data acquisition unit and a payload data handling unit. A ground test system is also developed to test SOX. The test results show that the design goals of the spectrometer system have been achieved. (authors)

  8. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, David J.; Shikhaliev, Polad M.; Matthews, Kenneth L. [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803-4001 (United States); Hogstrom, Kenneth R., E-mail: hogstrom@lsu.edu; Carver, Robert L.; Gibbons, John P. [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 and Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803-4001 (United States); Clarke, Taylor; Henderson, Alexander; Liang, Edison P. [Physics and Astronomy Department, Rice University, 6100 Main MS-61, Houston, Texas 77005-1827 (United States)

    2015-09-15

    Purpose: The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. Methods: An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed using a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7–20 MeV) of an Elekta Infinity radiotherapy accelerator. Results: Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to slightly lower

  9. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators.

    Science.gov (United States)

    McLaughlin, David J; Hogstrom, Kenneth R; Carver, Robert L; Gibbons, John P; Shikhaliev, Polad M; Matthews, Kenneth L; Clarke, Taylor; Henderson, Alexander; Liang, Edison P

    2015-09-01

    The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed using a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7-20 MeV) of an Elekta Infinity radiotherapy accelerator. Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to slightly lower energies. Energy calibration

  10. Crystal-diffraction spectrometer of increased efficiency

    International Nuclear Information System (INIS)

    Saukov, A.I.; Gornitsyn, G.A.; Morozov, N.A.

    1985-01-01

    The geometry of the spectrometer is illustrated in this paper. An attempt is made to achieve optimal design of the spectrometer by finding the coefficient of reflection of the gamma radiation from the various Ge planes. In these experiments, the Du Mond design was used in the spectrometer. Illustrations are provided to explain dependence of the relative efficiency upon the energy of the gamma quanta

  11. MEMS based digital transform spectrometers

    Science.gov (United States)

    Geller, Yariv; Ramani, Mouli

    2005-09-01

    Earlier this year, a new breed of Spectrometers based on Micro-Electro-Mechanical-System (MEMS) engines has been introduced to the commercial market. The use of these engines combined with transform mathematics, produces powerful spectrometers at unprecedented low cost in various spectral regions.

  12. Comparison of incidences of normal tissue complications with tumor response in a phase III trial comparing heat plus radiation to radiation alone

    International Nuclear Information System (INIS)

    Dewhirst, M.W.; Sim, D.A.; Grochowski, K.J.

    1984-01-01

    The success of hyperthermia (/sup Δ/) as an adjuvant to radiation (XRT) will depend on whether the increase in tumor control is greater than that for normal tissue reactions. One hundred and thirty dogs and cats were stratified by histology and randomized to receive XRT (460 rads per fraction, two fractions per week, for eight fractions) or /sup Δ/ + XRT (30 min. at 44 +-2 0 C; one fraction per week, four fractions; immediately prior to XRT). Heat induced changes in tumor and normal tissue responses were made by comparing ratios of incidence for /sup Δ/ + XRT and XRT alone (TRR; Thermal Relative Risk). Change in tumor response duration was calculated from statistical analysis of response duration curves (RRR; Relative Relapse Rate). Heat increased early normal tissue reactions (moist desquamation and mucositis by a factor of 1.08. Tumor complete response, by comparison, was significantly improved (TRR = 2.12, p < .001). Late skin fibrosis was also increased (TRR = 1.51), but the prolongation in tumor response was greater (RRR 1.85). The degree of thermal enhancement for all tissues was dependent on the minimum temperature achieved on the first treatment, but the values for tumor were consistently greater than those achieved for normal tissues

  13. Pelvic incidence variation among individuals: functional influence versus genetic determinism.

    Science.gov (United States)

    Chen, Hong-Fang; Zhao, Chang-Qing

    2018-03-20

    Pelvic incidence has become one of the most important sagittal parameters in spinal surgery. Despite its great importance, pelvic incidence can vary from 33° to 85° in the normal population. The reasons for this great variability in pelvic incidence remain unexplored. The objective of this article is to present some possible interpretations for the great variability in pelvic incidence under both normal and pathological conditions and to further understand the determinants of pelvic incidence from the perspective of the functional requirements for bipedalism and genetic backgrounds via a literature review. We postulate that both pelvic incidence and pelvic morphology may be genetically predetermined, and a great variability in pelvic incidence may already exist even before birth. This great variability may also serve as a further reminder that the sagittal profile, bipedal locomotion mode, and genetic background of every individual are unique and specific, and clinicians should avoid making universally applying broad generalizations of pelvic incidence. Although PI is an important parameter and there are many theories behind its variability, we still do not have clear mechanistic answers.

  14. The monochromatic imaging mode of a RITA-type neutron spectrometer

    International Nuclear Information System (INIS)

    Bahl, C.R.H.; Andersen, P.; Klausen, S.N.; Lefmann, K.

    2004-01-01

    The imaging monochromatic mode of a neutron spectrometer with a multi-bladed RITA analyser system is so far unexplored. We present analytical calculations that define the mode. It is shown that the mode can be realised for PG (0 0 2) analyser crystals, from incident energies of about 3.2 meV and up, allowing the important cases of 3.7, 5.0 and 13.7 meV. Due to beam divergence, the neutron rays from neighbouring analyser blades are found to overlap slightly. Hence, the optimal use of the monochromatic imaging mode would be found by employing an adjustable radial collimator to limit the spread of the ray from each analyser blade

  15. The monochromatic imaging mode of a RITA-type neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Bahl, C.R.H. [Department of Materials Research, Riso National Laboratory, Building 227, Frederiksborgvej 399, DK-4000 Roskilde (Denmark) and Department of Physics, Technical University of Denmark, DK-2800 Lyngby (Denmark)]. E-mail: christian.bahl@risoe.dk; Andersen, P. [Department of Materials Research, Riso National Laboratory, Building 227, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Niels Bohr Institute for Astronomy, Physics and Geophysics, University of Copenhagen, DK-2100 Copenhagen (Denmark); Klausen, S.N. [Department of Materials Research, Riso National Laboratory, Building 227, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Lefmann, K. [Department of Materials Research, Riso National Laboratory, Building 227, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

    2004-12-01

    The imaging monochromatic mode of a neutron spectrometer with a multi-bladed RITA analyser system is so far unexplored. We present analytical calculations that define the mode. It is shown that the mode can be realised for PG (0 0 2) analyser crystals, from incident energies of about 3.2 meV and up, allowing the important cases of 3.7, 5.0 and 13.7 meV. Due to beam divergence, the neutron rays from neighbouring analyser blades are found to overlap slightly. Hence, the optimal use of the monochromatic imaging mode would be found by employing an adjustable radial collimator to limit the spread of the ray from each analyser blade.

  16. Electro-Optical Imaging Fourier-Transform Spectrometer

    Science.gov (United States)

    Chao, Tien-Hsin; Zhou, Hanying

    2006-01-01

    An electro-optical (E-O) imaging Fourier-transform spectrometer (IFTS), now under development, is a prototype of improved imaging spectrometers to be used for hyperspectral imaging, especially in the infrared spectral region. Unlike both imaging and non-imaging traditional Fourier-transform spectrometers, the E-O IFTS does not contain any moving parts. Elimination of the moving parts and the associated actuator mechanisms and supporting structures would increase reliability while enabling reductions in size and mass, relative to traditional Fourier-transform spectrometers that offer equivalent capabilities. Elimination of moving parts would also eliminate the vibrations caused by the motions of those parts. Figure 1 schematically depicts a traditional Fourier-transform spectrometer, wherein a critical time delay is varied by translating one the mirrors of a Michelson interferometer. The time-dependent optical output is a periodic representation of the input spectrum. Data characterizing the input spectrum are generated through fast-Fourier-transform (FFT) post-processing of the output in conjunction with the varying time delay.

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

    International Nuclear Information System (INIS)

    Denne, B.; Hinnov, E.

    1984-04-01

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

  18. Charged particle scintillation mass spectrometer

    International Nuclear Information System (INIS)

    Baranov, P.S.; Zhuravlev, E.E.; Nafikov, A.A.; Osadchi , A.I.; Raevskij, V.G.; Smirnov, P.A.; Cherepnya, S.N.; Yanulis, Yu.P.

    1982-01-01

    A scintillation mass-spectrometer for charged particle identification by the measured values of time-of-flight and energy operating on line with the D-116 computer is described. Original time detectors with 100x100x2 mm 3 and 200x2 mm 2 scintillators located on the 1- or 2 m path length are used in the spectrometer. The 200x200x200 mm 3 scintillation unit is used as a E-counter. Time-of-flight spectra of the detected particles on the 2 m path length obtained in spectrometer test in the beam of charged particles escaping from the carbon target at the angle of 130 deg under 1.2 GeV bremsstrahlung beam of the ''Pakhra'' PIAS synchrotron are presented. Proton and deuteron energy spectra as well as mass spectrum of all the particles detected by the spectrometer are given. Mass resolution obtained on the 2 m path length for π-mesons is +-25%, for protons is +-5%, for deuterons is +-3%

  19. SOUND TRANSMISSION LOSS OF A DOUBLE-LEAF SOLID-MICROPERFORATED PARTITION UNDER NORMAL INCIDENCE OF ACOUSTIC LOADING

    Directory of Open Access Journals (Sweden)

    Ahmad Yusuf Ismail

    2011-12-01

    Full Text Available 0 0 1 332 1894 International Islamic University 15 4 2222 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} The micro-perforated panel (MPP is recently well-known as an alternative ‘green‘ sound absorber replacing the conventional porous materials. Constructed from a solid panel which provides a non-abrassive structure and also an optically attractive surface, there gives a feasibility to implement such a panel inside a vehicle cabin. This paper is the preliminary study to investigate the sound transmission loss (TL of a solid panel coupled with a micro-perforated panel to form a doube-leaf partition which is already known as a lightweigth stucture for noise insulation in vehicles and buildings. The mathematical model for the TL subjected to normal incidence of acoustic excitation is derived. The results show that its performance substantially improves at the troublesome frequency of mass-air-mass resonance which occurs in the conventional double-leaf solid partition. This is important particularly for the noise source predominant at low frequencies. This can also be controlled by tuning the hole size and number as well as the air gap between the panels.  ABSTRAK: Panel bertebuk mikro (micro-perforated panel (MPP kebelakangan ini dikenali sebagai alternatif penyerap bunyi yang mesra alam menggantikan bahan berliang lazim. Dibina daripada satu panel padu yang memberikan satu struktur tak lelas dan juga satu permukaan yang menarik, ia memberikan kemungkinan penggunaan panel tersebut di dalam kabin kenderaan. Tesis ini merupakan kajian permulaan dalam mengkaji hilang pancaran bunyi

  20. Digital Spectrometers for Interplanetary Science Missions

    Science.gov (United States)

    Jarnot, Robert F.; Padmanabhan, Sharmila; Raffanti, Richard; Richards, Brian; Stek, Paul; Werthimer, Dan; Nikolic, Borivoje

    2010-01-01

    A fully digital polyphase spectrometer recently developed by the University of California Berkeley Wireless Research Center in conjunction with the Jet Propulsion Laboratory provides a low mass, power, and cost implementation of a spectrum channelizer for submillimeter spectrometers for future missions to the Inner and Outer Solar System. The digital polyphase filter bank spectrometer (PFB) offers broad bandwidth with high spectral resolution, minimal channel-to-channel overlap, and high out-of-band rejection.

  1. Monte Carlo calculations of ligth-ion sputtering as a function of the incident angle

    International Nuclear Information System (INIS)

    Haggmark, L.G.; Biersack, J.P.

    1980-01-01

    The sputtering of metal surfaces by light ions has been studied as a function of the incident angle using an extension of the TRIM Monte Carlo computer program. Sputtering yields were calculated at both normal and oblique angles of incidence for H, D, T, and 4 He impinging on Ni, Mo, and Au targets with energies <= 10 keV. Direct comparisons are made with the most recent experimental and theoretical results. There is generally good agreement with the experimental data although our calculated maximum in the yield usually occurs at a smaller incident angle, measured from the surface normal. The enhancement of the yield at large incident angles over that at normal incidence is observed to be a complex function of the incident ion's energy and mass and the target's atomic weight and surface binding energy. (orig.)

  2. Analog and digital dividers for mass spectrometers

    International Nuclear Information System (INIS)

    Osipov, A.K.

    1980-01-01

    Errors of four different types of stress dividers used in statical mass-spectrometers for determination of mass number by accelerating stress are analyzed. The simplest flowsheet of the analog divider comprises operation amplifier, in the chain of the negative feedback of which a multiplication device on differential cascade is switched- in. This analog divider has high sensitivity to temperature and high error approximately 5%. Application of the multiplier on differential cascade with normalization permits to increase temperature stability and decrease the error up to 1%. Another type of the analog divider is a logarithmic divider the error of which is constant within the whole operation range and it constitutes 1-5%. The digital divider with a digital-analog transformer (DAT) has the error of +-0.015% which is determined by the error of detectors and resistance of keys in the locked state. Considered is the design of a divider based on transformation of the inlet stress into the time period. The error of the divider is determined in this case mainly by stress of the zero shift of the operation amplifier (it should be compensated) and relative threshold stability of the comparator triggering which equals (2-3)x10 -4 . It is noted that the divider with DAT application and the divider with the use of stress transformation within the time period are most perspective ones for statical mass-spectrometers [ru

  3. The management of radiation treatment error through incident learning

    International Nuclear Information System (INIS)

    Clark, Brenda G.; Brown, Robert J.; Ploquin, Jodi L.; Kind, Anneke L.; Grimard, Laval

    2010-01-01

    Purpose: To assess efficacy of an incident learning system in the management of error in radiation treatment. Materials and methods: We report an incident learning system implementation customized for radiation therapy where any 'unwanted or unexpected change from normal system behaviour that causes or has the potential to cause an adverse effect to persons or equipment' is reported, investigated and learned from. This system thus captures near-miss (potential) and actual events. Incidents are categorized according to severity, type and origin. Results: Our analysis spans a period of 3 years with an average accrual of 11.6 incidents per week. We found a significant reduction in actual incidents of 28% and 47% in the second and third year when compared to the first year (p < 0.001), which we attribute to the many interventions prompted by the analysis of incidents reported. We also saw a similar significant reduction in incidents generated at the treatment unit correlating with the introduction of direct treatment parameter transfer and electronic imaging (p < 0.001). Conclusions: Implementation of an incident learning system has helped us to establish a just environment where all staff members report deviations from normal system behaviour and thus generate evidence to initiate safety improvements.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Combined raman spectrometer/laser-induced breakdown spectrometer design concept

    Science.gov (United States)

    Bazalgette Courrèges-Lacoste, Gregory; Ahlers, Berit; Boslooper, Erik; Rull-Perez, Fernando; Maurice, Sylvestre

    2017-11-01

    Amongst the different instruments that have been preselected to be on-board the Pasteur payload on ExoMars is the Raman/ Laser Induced Breakdown Spectroscopy (LIBS) instrument. Raman spectroscopy and LIBS will be integrated into a single instrument sharing many hardware commonalities. An international team under the lead of TNO has been gathered to produce a design concept for a combined Raman Spectrometer/ LIBS Elegant Bread-Board (EBB). The instrument is based on a specifically designed extremely compact spectrometer with high resolution over a large wavelength range, suitable for both Raman spectroscopy and LIBS measurements. Low mass, size and resources are the main drivers of the instrument's design concept. The proposed design concept, realization and testing programme for the combined Raman/ LIBS EBB is presented as well as background information on Raman and LIBS.

  6. A gamma-gamma coincidence/anticoincidence spectrometer for low-level cosmogenic (22)Na/(7)Be activity ratio measurement.

    Science.gov (United States)

    Zhang, Weihua; Ungar, Kurt; Stukel, Matthew; Mekarski, Pawel

    2014-04-01

    In this study, a digital gamma-gamma coincidence/anticoincidence spectrometer was developed and examined for low-level cosmogenic (22)Na and (7)Be in air-filter sample monitoring. The spectrometer consists of two bismuth germanate scintillators (BGO) and an XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The spectrometer design allows a more selective measurement of (22)Na with a significant background reduction by gamma-gamma coincidence events processing. Hence, the system provides a more sensitive way to quantify trace amounts of (22)Na than normal high resolution gamma spectrometry providing a critical limit of 3 mBq within a 20 h count. The use of a list-mode data acquisition technique enabled simultaneous determination of (22)Na and (7)Be activity concentrations using a single measurement by coincidence and anticoincidence mode respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Efficient mass calibration of magnetic sector mass spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Roddick, J C

    1997-12-31

    Magnetic sector mass spectrometers used for automatic acquisition of precise isotopic data are usually controlled with Hall probes and software that uses polynomial equations to define and calibrate the mass-field relations required for mass focusing. This procedure requires a number of reference masses and careful tuning to define and maintain an accurate mass calibration. A simplified equation is presented and applied to several different magnetically controlled mass spectrometers. The equation accounts for nonlinearity in typical Hall probe controlled mass-field relations, reduces calibration to a linear fitting procedure, and is sufficiently accurate to permit calibration over a mass range of 2 to 200 amu with only two defining masses. Procedures developed can quickly correct for normal drift in calibrations and compensate for drift during isotopic analysis over a limited mass range such as a single element. The equation is: Field A{center_dot}Mass{sup 1/2} + B{center_dot}(Mass){sup p} where A, B, and p are constants. The power value p has a characteristic value for a Hall probe/controller and is insensitive to changing conditions, thus reducing calibration to a linear regression to determine optimum A and B. (author). 1 ref., 1 tab., 6 figs.

  8. Recent ion optics and mass spectrometers

    International Nuclear Information System (INIS)

    Matsuda, Hisashi

    1976-01-01

    The establishment of the third order approximation method for computing the orbit of the ion optical system for mass spectrometers and the completion of its computer program are reported. A feature of this orbit computation is in that the effect of the fringing field can be considered with the accuracy of third order approximation. Several new ion optical systems for mass spectrometers have been proposed by using such orbit computing programs. Brief explanation and the description on the future prospect and problems are made on the following items: the vertual image double focusing mass spectrometer, the second order double focusing mass spectrometer, the E x B superposed field mass spectrometer, and the apparatus with a cylindrical electric field and Q-lens. In the E x B superposed field with Matsuda plates, if the magnetic field is generated by an electromagnet instead of a permanent magnet, the dispersion of mass and energy can be changed at will. The Matsuda plates are known as the auxiliary electrodes positioned at the top and bottom of a cylindrical capacitor. Utilizing those characteristics, a zoom spectrometer can be made, with which only a necessary part of mass spectra can be investigated in detail, but the whole spectra are investigated roughly. In addition, the distribution of energy can be investigated simultaneously after the separation of ionic mass similarly to the parabola apparatus. (Iwakiri, K.)

  9. Development of an ion time-of-flight spectrometer for neutron depth profiling

    Science.gov (United States)

    Cetiner, Mustafa Sacit

    signal. Without loss of generality, the secondary signal is obtained by the passage of the ion through a thin carbon foil, which produces ion-induced secondary electron emission (IISEE). The time-of-flight spectrometer physically acts as an ion/electron separator. The electrons that enter the active volume of the spectrometer are transported onto the microchannel plate detector to generate the secondary signal. The electron optics can be designed in variety of ways depending on the nature of the measurement and physical requirements. Two ion time-of-flight spectrometer designs are introduced: the parallel electric and magnetic (PEM) field spectrometer and the cross electric and magnetic (CEM) field spectrometer. The CEM field spectrometers have been extensively used in a wide range of applications where precise mass differentiation is required. The PEM field spectrometers have lately found interest in mass spectroscopy applications. The application of the PEM field spectrometer for energy measurements is a novel approach. The PEM field spectrometer used in the measurements employs axial electric and magnetic fields along the nominal direction of the incident ion. The secondary electrons are created by a thin carbon foil on the entrance disk and transported on the microchannel plate that faces the carbon foil. The initial angular distribution of the secondary electrons has virtually no effect on the transport time of the secondary electrons from the surface of the carbon foil to the electron microchannel plate detector. Therefore, the PEM field spectrometer can offer high-resolution energy measurement for relatively lower electric fields. The measurements with the PEM field spectrometer were made with the Tandem linear particle accelerator at the IBM T. J. Watson Research Center at Yorktown Heights, NY. The CEM field spectrometer developed for the thesis employs axial electric field along the nominal direction of the ion, and has perpendicular magnetic field. As the

  10. The TRIUMF low energy pion spectrometer and channel

    International Nuclear Information System (INIS)

    Sobie, R.J.; Drake, T.E.; Barnett, B.M.; Erdman, K.L.; Gyles, W.; Johnson, R.R.; Roser, H.W.; Tacik, R.; Blackmore, E.W.; Gill, D.R.

    1983-08-01

    A low energy pion spectrometer has been developed for use with the TRIUMF M13 pion channel. The combined channel and spectrometer resolution is presently 1.1 MeV at T = 50 MeV. This is limited by the amount of gas and detector material in the spectrometer in addition to the inherent resolution of the channel. Improvements to both the spectrometer and channel are discussed

  11. Electron volt neutron spectrometers

    International Nuclear Information System (INIS)

    Pietropaolo, A.; Senesi, R.

    2011-01-01

    The advent of pulsed neutron sources has made available intense fluxes of epithermal neutrons (500 meV ≤E≤100 eV ). The possibility to open new investigations on condensed matter with eV neutron scattering techniques, is related to the development of methods, concepts and devices that drive, or are inspired by, emerging studies at this energy scale. Electron volt spectrometers have undergone continuous improvements since the construction of the first prototype instruments, but in the last decade major breakthroughs have been accomplished in terms of resolution and counting statistics, leading, for example, to the direct measurement of the proton 3-D Born–Oppenheimer potential in any material, or to quantitatively probe nuclear quantum effects in hydrogen bonded systems. This paper reports on the most effective methods and concepts for energy analysis and detection, as well as devices for the optimization of electron volt spectrometers for different applications. This is set in the context of the progress made up to date in instrument development. Starting from early stages of development of the technique, particular emphasis will be given to the Vesuvio eV spectrometer at the ISIS neutron source, the first spectrometer where extensive scientific, as well as research and development programmes have been carried out. The potential offered by this type of instrumentation, from single particle excitations to momentum distribution studies, is then put in perspective into the emerging fields of eV spectroscopy applied to cultural heritages and neutron irradiation effects in electronics. - Highlights: ► Neutron spectrometers at eV energies. ► Methods and techniques for eV neutrons counting at spallation sources. ► Scattering, imaging and radiation hardness tests with multi-eV neutrons.

  12. A magnetic-lens - mini-orange coincidence spectrometer

    International Nuclear Information System (INIS)

    Bargholtz, C.; Holmberg, L.; Ruus, N.; Tegner, P.E.; Weiss, G.

    1997-04-01

    A coincidence spectrometer consisting of a Gerholm type magnetic lens and a permanent magnet mini-orange spectrometer is described. Electron-electron or electron-positron coincidences may be registered in various angular settings. The spectrometer has been developed mainly to search for anomalous contributions to Bhabha scattering or positrons and is at present used for such studies. 6 refs

  13. Ultra-Wideband Optical Modulation Spectrometer (OMS) Development

    Science.gov (United States)

    Gardner, Jonathan (Technical Monitor); Tolls, Volker

    2004-01-01

    The optical modulation spectrometer (OMS) is a novel, highly efficient, low mass backend for heterodyne receiver systems. Current and future heterodyne receiver systems operating at frequencies up to a few THz require broadband spectrometer backends to achieve spectral resolutions of R approximately 10(exp 5) to 10(exp 6) to carry out many important astronomical investigations. Among these are observations of broad emission and absorption lines from extra-galactic objects at high redshifts, spectral line surveys, and observations of planetary atmospheres. Many of these lines are pressure or velocity broadened with either large half-widths or line wings extending over several GHz. Current backend systems can cover the needed bandwidth only by combining the output of several spectrometers, each with typically up to 1 GHz bandwidth, or by combining several frequency-shifted spectra taken with a single spectrometer. An ultra-wideband optical modulation spectrometer with 10 - 40 GHz bandwidth will enable broadband ob- servations without the limitations and disadvantages of hybrid spectrometers. Spectrometers like the OMS will be important for both ground-based observatories and future space missions like the Single Aperture Far-Infrared Telescope (SAFIR) which might carry IR/submm array heterodyne receiver systems requiring a spectrometer for each array pixel. Small size, low mass and small power consumption are extremely important for space missions. This report summarizes the specifications developed for the OMS and lists already identified commercial parts. The report starts with a review of the principle of operation, then describes the most important components and their specifications which were derived from theory, and finishes with a conclusion and outlook.

  14. Mid infrared MEMS FTIR spectrometer

    Science.gov (United States)

    Erfan, Mazen; Sabry, Yasser M.; Mortada, Bassem; Sharaf, Khaled; Khalil, Diaa

    2016-03-01

    In this work we report, for the first time to the best of our knowledge, a bulk-micromachined wideband MEMS-based spectrometer covering both the NIR and the MIR ranges and working from 1200 nm to 4800 nm. The core engine of the spectrometer is a scanning Michelson interferometer micro-fabricated using deep reactive ion etching (DRIE) technology. The spectrum is obtained using the Fourier Transform techniques that allows covering a very wide spectral range limited by the detector responsivity. The moving mirror of the interferometer is driven by a relatively large stroke electrostatic comb-drive actuator. Zirconium fluoride (ZrF4) multimode optical fibers are used to connect light between the white light source and the interferometer input, as well as the interferometer output to a PbSe photoconductive detector. The recorded signal-to-noise ratio is 25 dB at the wavelength of 3350 nm. The spectrometer is successfully used in measuring the absorption spectra of methylene chloride, quartz glass and polystyrene film. The presented solution provides a low cost method for producing miniaturized spectrometers in the near-/mid-infrared.

  15. Novette diagnostic support. Final report

    International Nuclear Information System (INIS)

    Cirigliano, R.; Franco, E.; Koppel, L.; Rodrigues, B.; Smith, J.

    1985-02-01

    The primary research areas were the following: (1) contribute x-ray diagnostic, experimental, and data reduction and analysis support for the Novette DANTE x-ray spectrometer experiments. This effort was expanded to improve the overall quality of the Novette database; (2) experimental and calculational characterization of the x-ray imaging properties of an ellipsoidal x-ray collection optic serving as a sensitivity enhancing component of the Transmission Grating Streak Spectrometer; (3) performance simulation of the x-ray dispersion properties of candidate x-ray laser cavity, normal incidence end-mirror optics; (4) contribute x-ray diagnostic, experimental, and data reduction and analysis support for the Novette Henway crystal spectrometer and the MCPIGS microchannel plate intensified grazing incident spectrometer experiments; and (5) perform a technical performance vs cost evaluation of commercially available hardware required to perform the NOVA neutron time-of-flight experiments

  16. Gas-dust-impact mass spectrometer

    CERN Document Server

    Semkin, N D; Myasnikov, S V; Pomelnikov, R A

    2002-01-01

    Paper describes design of a mass spectrometer to study element composition of micro meteorite and man-made particles in space. Paper describes a way to improve resolution of mass spectrometer based on variation of parameters of accelerating electric field in time. The advantage of the given design of mass spectrometer in comparison with similar ones is its large operating area and higher resolution at the comparable weight and dimensions. Application of a combined design both for particles and for gas enables to remove space vehicle degassing products from the spectrum and, thus, to improve reliability of the acquired information, as well as, to acquire information on a gas component of the external atmosphere of a space vehicle

  17. Measurement of double differential cross sections of secondary neutrons in the incident energy range 9-13 MeV

    International Nuclear Information System (INIS)

    Tang Hongqing; Qi Bujia; Zhou Zuying; Sa Jun; Ke Zunjian; Sui Qingchang; Xia Haihong; Shen Guanren

    1992-01-01

    The status and technique of double differential cross section measurement of secondary neutrons in the incident neutron energy range 9 to 13 MeV is reviewed with emphasis on the work done at CIAE. There are scarce measurements of secondary neutron double differential cross sections in this energy region up to now. A main difficulty for this is lack of an applicable monoenergetic neutron source. When monoenergetic neutron energy reaches 8 Me/v, the break-up neutrons from the d + D or p + T reaction starts to become significant. It is difficult to get a pure secondary neutron spectrum induced only by monoenergetic neutrons. To solve this problem an abnormal fast neutron TOF facility was designed and tested. Double differential neutron emission cross sections of 238 U and 209 Bi at 10 MeV were obtained by combining the data measured by both normal and abnormal TOF spectrometers and a good agreement between measurement and calculation was achieved

  18. Memory Binding Test Predicts Incident Amnestic Mild Cognitive Impairment.

    Science.gov (United States)

    Mowrey, Wenzhu B; Lipton, Richard B; Katz, Mindy J; Ramratan, Wendy S; Loewenstein, David A; Zimmerman, Molly E; Buschke, Herman

    2016-07-14

    The Memory Binding Test (MBT), previously known as Memory Capacity Test, has demonstrated discriminative validity for distinguishing persons with amnestic mild cognitive impairment (aMCI) and dementia from cognitively normal elderly. We aimed to assess the predictive validity of the MBT for incident aMCI. In a longitudinal, community-based study of adults aged 70+, we administered the MBT to 246 cognitively normal elderly adults at baseline and followed them annually. Based on previous work, a subtle reduction in memory binding at baseline was defined by a Total Items in the Paired (TIP) condition score of ≤22 on the MBT. Cox proportional hazards models were used to assess the predictive validity of the MBT for incident aMCI accounting for the effects of covariates. The hazard ratio of incident aMCI was also assessed for different prediction time windows ranging from 4 to 7 years of follow-up, separately. Among 246 controls who were cognitively normal at baseline, 48 developed incident aMCI during follow-up. A baseline MBT reduction was associated with an increased risk for developing incident aMCI (hazard ratio (HR) = 2.44, 95% confidence interval: 1.30-4.56, p = 0.005). When varying the prediction window from 4-7 years, the MBT reduction remained significant for predicting incident aMCI (HR range: 2.33-3.12, p: 0.0007-0.04). Persons with poor performance on the MBT are at significantly greater risk for developing incident aMCI. High hazard ratios up to seven years of follow-up suggest that the MBT is sensitive to early disease.

  19. Visible-infrared micro-spectrometer based on a preaggregated silver nanoparticle monolayer film and an infrared sensor card

    Science.gov (United States)

    Yang, Tao; Peng, Jing-xiao; Ho, Ho-pui; Song, Chun-yuan; Huang, Xiao-li; Zhu, Yong-yuan; Li, Xing-ao; Huang, Wei

    2018-01-01

    By using a preaggregated silver nanoparticle monolayer film and an infrared sensor card, we demonstrate a miniature spectrometer design that covers a broad wavelength range from visible to infrared with high spectral resolution. The spectral contents of an incident probe beam are reconstructed by solving a matrix equation with a smoothing simulated annealing algorithm. The proposed spectrometer offers significant advantages over current instruments that are based on Fourier transform and grating dispersion, in terms of size, resolution, spectral range, cost and reliability. The spectrometer contains three components, which are used for dispersion, frequency conversion and detection. Disordered silver nanoparticles in dispersion component reduce the fabrication complexity. An infrared sensor card in the conversion component broaden the operational spectral range of the system into visible and infrared bands. Since the CCD used in the detection component provides very large number of intensity measurements, one can reconstruct the final spectrum with high resolution. An additional feature of our algorithm for solving the matrix equation, which is suitable for reconstructing both broadband and narrowband signals, we have adopted a smoothing step based on a simulated annealing algorithm. This algorithm improve the accuracy of the spectral reconstruction.

  20. A time-of-flight spectrometer for neutron diffraction under high pressure or at high temperature

    International Nuclear Information System (INIS)

    Roult, G.; Buevoz, J.L.

    1975-01-01

    For high pressure neutron diffraction studies (40 kilobars) the sample is placed in a very thick cell. In order to allow the neutron beam to go through the cell loosing as little intensity as possible, the inner part is kept solid while the external part has some windows facing the incident and reflected beam. The window dimensions are small (a few millimeters wide and a few centimeters long). There are two alternatives: to have the window either in a perpendicular plane or in a plane parallel to the axis. In the first case a fixed wavelength spectrometer can be used but the sample is small and the contribution of the cell to the diffraction pattern is relatively great. In the second case samples can be something like ten times greater and the cell contribution can be eliminated but a fixed wavelength spectrometer cannot be used. Thus the time-of-flight method is very convenient. The second alternative was chosen

  1. Higher Levels of Albuminuria within the Normal Range Predict Incident Hypertension

    OpenAIRE

    Forman, John P.; Fisher, Naomi D.L.; Schopick, Emily L.; Curhan, Gary C.

    2008-01-01

    Higher levels of albumin excretion within the normal range are associated with cardiovascular disease in high-risk individuals. Whether incremental increases in urinary albumin excretion, even within the normal range, are associated with the development of hypertension in low-risk individuals is unknown. This study included 1065 postmenopausal women from the first Nurses’ Health Study and 1114 premenopausal women from the second Nurses’ Health Study who had an albumin/creatinine ratio

  2. Study of neutron spectrometers for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Kaellne, Jan

    2005-11-15

    A review is presented of the developments in the field of neutron emission spectrometry (NES) which is of relevance for identifying the role of NES diagnostics on ITER and selecting suitable instrumentation. Neutron spectrometers will be part of the ITER neutron diagnostic complement and this study makes a special effort to examine which performance characteristics the spectrometers should possess to provide the best burning plasma diagnostic information together with neutron cameras and neutron yield monitors. The performance of NES diagnostics is coupled to how much interface space can be provided which has lead to an interest to find compact instruments and their NES capabilities. This study assesses all known spectrometer types of potential interest for ITER and makes a ranking of their performance (as demonstrated or projected), which, in turn, are compared with ITER measurement requirements as a reference; the ratio of diagnostic performance to interface cost for different spectrometers is also discussed for different spectrometer types. The overall result of the study is an assessment of which diagnostic functions neutron measurements can provide in burning plasma fusion experiments on ITER and the role that NES can play depending on the category of instrument installed. Of special note is the result that much higher quality diagnostic information can be obtained from neutron measurements with total yield monitors, profile flux cameras and spectrometers when the synergy in the data is considered in the analysis and interpretation.

  3. Multi-spectrometer calibration transfer based on independent component analysis.

    Science.gov (United States)

    Liu, Yan; Xu, Hao; Xia, Zhenzhen; Gong, Zhiyong

    2018-02-26

    Calibration transfer is indispensable for practical applications of near infrared (NIR) spectroscopy due to the need for precise and consistent measurements across different spectrometers. In this work, a method for multi-spectrometer calibration transfer is described based on independent component analysis (ICA). A spectral matrix is first obtained by aligning the spectra measured on different spectrometers. Then, by using independent component analysis, the aligned spectral matrix is decomposed into the mixing matrix and the independent components of different spectrometers. These differing measurements between spectrometers can then be standardized by correcting the coefficients within the independent components. Two NIR datasets of corn and edible oil samples measured with three and four spectrometers, respectively, were used to test the reliability of this method. The results of both datasets reveal that spectra measurements across different spectrometers can be transferred simultaneously and that the partial least squares (PLS) models built with the measurements on one spectrometer can predict that the spectra can be transferred correctly on another.

  4. Magnetic and electric deflector spectrometers for ion emission analysis from laser generated plasma

    Directory of Open Access Journals (Sweden)

    Torrisi Lorenzo

    2018-01-01

    Full Text Available The pulsed laser-generated plasma in vacuum and at low and high intensities can be characterized using different physical diagnostics. The charge particles emission can be characterized using magnetic, electric and magnet-electrical spectrometers. Such on-line techniques are often based on time-of-flight (TOF measurements. A 90° electric deflection system is employed as ion energy analyzer (IEA acting as a filter of the mass-to-charge ratio of emitted ions towards a secondary electron multiplier. It determines the ion energy and charge state distributions. The measure of the ion and electron currents as a function of the mass-to-charge ratio can be also determined by a magnetic deflector spectrometer, using a magnetic field of the order of 0.35 T, orthogonal to the ion incident direction, and an array of little ion collectors (IC at different angles. A Thomson parabola spectrometer, employing gaf-chromix as detector, permits to be employed for ion mass, energy and charge state recognition. Mass quadrupole spectrometry, based on radiofrequency electric field oscillations, can be employed to characterize the plasma ion emission. Measurements performed on plasma produced by different lasers, irradiation conditions and targets are presented and discussed. Complementary measurements, based on mass and optical spectroscopy, semiconductor detectors, fast CCD camera and Langmuir probes are also employed for the full plasma characterization. Simulation programs, such as SRIM, SREM, and COMSOL are employed for the charge particle recognition.

  5. Magnetic and electric deflector spectrometers for ion emission analysis from laser generated plasma

    Science.gov (United States)

    Torrisi, Lorenzo; Costa, Giuseppe; Ceccio, Giovanni; Cannavò, Antonino; Restuccia, Nancy; Cutroneo, Mariapompea

    2018-01-01

    The pulsed laser-generated plasma in vacuum and at low and high intensities can be characterized using different physical diagnostics. The charge particles emission can be characterized using magnetic, electric and magnet-electrical spectrometers. Such on-line techniques are often based on time-of-flight (TOF) measurements. A 90° electric deflection system is employed as ion energy analyzer (IEA) acting as a filter of the mass-to-charge ratio of emitted ions towards a secondary electron multiplier. It determines the ion energy and charge state distributions. The measure of the ion and electron currents as a function of the mass-to-charge ratio can be also determined by a magnetic deflector spectrometer, using a magnetic field of the order of 0.35 T, orthogonal to the ion incident direction, and an array of little ion collectors (IC) at different angles. A Thomson parabola spectrometer, employing gaf-chromix as detector, permits to be employed for ion mass, energy and charge state recognition. Mass quadrupole spectrometry, based on radiofrequency electric field oscillations, can be employed to characterize the plasma ion emission. Measurements performed on plasma produced by different lasers, irradiation conditions and targets are presented and discussed. Complementary measurements, based on mass and optical spectroscopy, semiconductor detectors, fast CCD camera and Langmuir probes are also employed for the full plasma characterization. Simulation programs, such as SRIM, SREM, and COMSOL are employed for the charge particle recognition.

  6. Limiting values for radionuclide concentration in the soil from remote spectrometer measurements

    International Nuclear Information System (INIS)

    Stuart, T.P.

    1977-08-01

    Spectrometers that remotely sense γ-rays in the soil are usually oriented with the normal to a planar surface perpendicular to the air-soil interface. When this is the case, and when the thickness of the detector is not greater than the linear dimensions that determine the aforementioned surface area, simple assumptions can be made to calculate high and low limits for factors that convert from photopeak count rates in the spectrometer to soil concentrations. An H.P. 65 calculator program is developed to calculate these two conversion factors as a function of detector altitude, counting rates from a single measurement with a point calibration source, shielding on the surface of the detector, and depth of activity in the soil. The assumption of an exponential decrease with depth allows the previously reported results of Beck et al to be applied to convert from soil concentration to dose rate at 1 m above the ground

  7. [Design of Dual-Beam Spectrometer in Spectrophotometer for Colorimetry].

    Science.gov (United States)

    Liu, Yi-xuan; Yan, Chang-xiang

    2015-07-01

    Spectrophotometers for colorimetry are usually composed of two independent and identical spectrometers. In order to reduce the volume of spectrophotometer for colorimetry, a design method of double-beam spectrometer is put forward. A traditional spectrometer is modified so that a new spectrometer can realize the function of double spectrometers, which is especially suitable for portable instruments. One slit is replaced by the double-slit, than two beams of spectrum can be detected. The working principle and design requirement of double-beam spectrometer are described. A spectrometer of portable spectrophotometer is designed by this method. A toroidal imaging mirror is used for the Czerny-Turner double-beam spectrometer in this paper, which can better correct astigmatism, and prevent the dual-beam spectral crosstalk. The results demonstrate that the double-beam spectrometer designed by this method meets the design specifications, with the spectral resolution less than 10 nm, the spectral length of 9.12 mm, and the volume of 57 mm x 54 mm x 23 mm, and without the dual-beam spectral overlap in the detector either. Comparing with a traditional spectrophotometer, the modified spectrophotometer uses a set of double-beam spectrometer instead of two sets of spectrometers, which can greatly reduce the volume. This design method can be specially applied in portable spectrophotometers, also can be widely applied in other double-beam spectrophotometers, which offers a new idea for the design of dual-beam spectrophotometers.

  8. Intracavity Laser Photoacoustic Spectrometer with High Sensitivity

    International Nuclear Information System (INIS)

    Mitrayana; Muslim; Wasono, M.A.J.

    2002-01-01

    A photo acoustic spectrometer set-up has been upgraded from an extra cavity into an intracavity configuration using a sealed-off CO 2 laser as the spectrometer's radiation source. The detection level of the upgrade Intracavity Photoacoustic Spectrometer (IPS) reached (200 ± 50) ppt for C 2 H 4 and (20 ± 5) ppt for SF 6 with response time (6.6 ± 0.2) s. (author)

  9. Evaluation of the ROTAX spectrometer

    International Nuclear Information System (INIS)

    Tietze-Jaensch, H.; Schmidt, W.; Geick, R.

    1997-01-01

    After installation of the new-type rotating crystal analyser spectrometer ROTAX at ISIS, we report on practical experience and describe its current status. The rotating analyser technique works feasibly and reliably and provides an ultimate scan flexibility on a pulsed time-of-flight neutron spectrometer. The spinning analyser achieves a mulitplex advantage factor of ca. 50 without compromising the resolution of the instrument. Despite these instrument merits its individual beam position at ISIS has only an unsatisfactorily weak flux, thus hindering this instrument yet to become fully competitive with other high-performance neutron spectrometers based at high-flux reactors. However, we strongly recommend a ROTAX-type instrument to be emphasized when the instrumentation suite of the future European spallation source ESS will come under scrutiny. (orig.)

  10. Handheld spectrometers: the state of the art

    Science.gov (United States)

    Crocombe, Richard A.

    2013-05-01

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

  11. Gamma-ray spectrometer utilizing xenon at high pressure

    International Nuclear Information System (INIS)

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

    1994-01-01

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

  12. Miniature Raman spectrometer development

    Science.gov (United States)

    Bonvallet, Joseph; Auz, Bryan; Rodriguez, John; Olmstead, Ty

    2018-02-01

    The development of techniques to rapidly identify samples ranging from, molecule and particle imaging to detection of high explosive materials, has surged in recent years. Due to this growing want, Raman spectroscopy gives a molecular fingerprint, with no sample preparation, and can be done remotely. These systems can be small, compact, lightweight, and with a user interface that allows for easy use and sample identification. Ocean Optics Inc. has developed several systems that would meet all these end user requirements. This talk will describe the development of different Ocean Optics Inc miniature Raman spectrometers. The spectrometer on a phone (SOAP) system was designed using commercial off the shelf (COTS) components, in a rapid product development cycle. The footprint of the system measures 40x40x14 mm (LxWxH) and was coupled directly to the cell phone detector camera optics. However, it gets roughly only 40 cm-1 resolution. The Accuman system is the largest (290x220X100 mm) of the three, but uses our QEPro spectrometer and get 7-11 cm-1 resolution. Finally, the HRS-30 measuring 165x85x40 mm is a combination of the other two systems. This system uses a modified EMBED spectrometer and gets 7-12 cm-1 resolution. Each of these units uses a peak matching algorithm that then correlates the results to the pre-loaded and customizable spectral libraries.

  13. Solar cell angle of incidence corrections

    Science.gov (United States)

    Burger, Dale R.; Mueller, Robert L.

    1995-01-01

    Literature on solar array angle of incidence corrections was found to be sparse and contained no tabular data for support. This lack along with recent data on 27 GaAs/Ge 4 cm by 4 cm cells initiated the analysis presented in this paper. The literature cites seven possible contributors to angle of incidence effects: cosine, optical front surface, edge, shadowing, UV degradation, particulate soiling, and background color. Only the first three are covered in this paper due to lack of sufficient data. The cosine correction is commonly used but is not sufficient when the incident angle is large. Fresnel reflection calculations require knowledge of the index of refraction of the coverglass front surface. The absolute index of refraction for the coverglass front surface was not known nor was it measured due to lack of funds. However, a value for the index of refraction was obtained by examining how the prediction errors varied with different assumed indices and selecting the best fit to the set of measured values. Corrections using front surface Fresnel reflection along with the cosine correction give very good predictive results when compared to measured data, except there is a definite trend away from predicted values at the larger incident angles. This trend could be related to edge effects and is illustrated by a use of a box plot of the errors and by plotting the deviation of the mean against incidence angle. The trend is for larger deviations at larger incidence angles and there may be a fourth order effect involved in the trend. A chi-squared test was used to determine if the measurement errors were normally distributed. At 10 degrees the chi-squared test failed, probably due to the very small numbers involved or a bias from the measurement procedure. All other angles showed a good fit to the normal distribution with increasing goodness-of-fit as the angles increased which reinforces the very small numbers hypothesis. The contributed data only went to 65 degrees

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

    Energy Technology Data Exchange (ETDEWEB)

    Semkow, T.M., E-mail: thomas.semkow@health.ny.gov [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Rensselaer, NY 12144 (United States); Bradt, C.J.; Beach, S.E.; Haines, D.K.; Khan, A.J.; Bari, A.; Torres, M.A.; Marrantino, J.C.; Syed, U.-F. [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201 (United States); Kitto, M.E. [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Rensselaer, NY 12144 (United States); Hoffman, T.J. [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201 (United States); Curtis, P. [Kiltel Systems, Inc., Clyde Hill, WA 98004 (United States)

    2015-11-01

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

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  16. Imaging spectrometer using a liquid crystal tunable filter

    Science.gov (United States)

    Chrien, Thomas G.; Chovit, Christopher; Miller, Peter J.

    1993-09-01

    A demonstration imaging spectrometer using a liquid crystal tunable filter (LCTF) was built and tested on a hot air balloon platform. The LCTF is a tunable polarization interference or Lyot filter. The LCTF enables a small, light weight, low power, band sequential imaging spectrometer design. An overview of the prototype system is given along with a description of balloon experiment results. System model performance predictions are given for a future LCTF based imaging spectrometer design. System design considerations of LCTF imaging spectrometers are discussed.

  17. High-efficiency improvement for high energy resolution experimental mode of DIANA spectrometer at materials and life science facility (MLF) of J-PARC

    International Nuclear Information System (INIS)

    Takahashi, Nobuaki; Shibata, Kaoru; Arai, Masatoshi; Sato, Taku J.

    2006-09-01

    DIANA is an indirect-geometry time-of-flight (TOF) spectrometer which is planed to install at Materials and Life science Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC). It has three exchangeable analyzer crystals, such as PG(002), Ge(311) and Si(111) for different energy transfer, momentum transfer and energy-resolution experiments. Normal experimental mode, either PG(002) or Ge(311) analyzer is used, shows moderate energy resolutions of 15μeV or 41λeV, respectively. We are especially aiming very high energy-resolution of 2 μeV by using Si(111) analyzer crystal together with high speed counter-rotating pulse-shaping choppers with each rotation frequency of 300 Hz as an optional setting for the spectrometer. Although such a high energy-resolution is attained, it is considerably inefficient having a very narrow incident energy (E i ) band if the pulse shaping chopper has only one slit. Therefore, we have designed multiple-slit chopper and have performed Monte-Carlo simulation to study Repetition Rate Multiplication (RRM) capability. RRM has been shown to be achievable by using multiple-slit pulse-shaping choppers. By the consideration of the contamination appeared between the neighbor two pulse-shaped bands, the number of slits has been optimized to eight. By using the 8-slit choppers, 23 pulse-shaped neutron energy bands have been available simultaneously within one measurements. Minimum 10 measurements with different phases of the choppers provide the continuous S(Q, ℎω) spectrum of -1.0 meV<ℎω<+3.4 meV. (author)

  18. A rapid method for creating qualitative images indicative of thick oil emulsion on the ocean's surface from imaging spectrometer data

    Science.gov (United States)

    Kokaly, Raymond F.; Hoefen, Todd M.; Livo, K. Eric; Swayze, Gregg A.; Leifer, Ira; McCubbin, Ian B.; Eastwood, Michael L.; Green, Robert O.; Lundeen, Sarah R.; Sarture, Charles M.; Steele, Denis; Ryan, Thomas; Bradley, Eliza S.; Roberts, Dar A.; ,

    2010-01-01

    This report describes a method to create color-composite images indicative of thick oil:water emulsions on the surface of clear, deep ocean water by using normalized difference ratios derived from remotely sensed data collected by an imaging spectrometer. The spectral bands used in the normalized difference ratios are located in wavelength regions where the spectra of thick oil:water emulsions on the ocean's surface have a distinct shape compared to clear water and clouds. In contrast to quantitative analyses, which require rigorous conversion to reflectance, the method described is easily computed and can be applied rapidly to radiance data or data that have been atmospherically corrected or ground-calibrated to reflectance. Examples are shown of the method applied to Airborne Visible/Infrared Imaging Spectrometer data collected May 17 and May 19, 2010, over the oil spill from the Deepwater Horizon offshore oil drilling platform in the Gulf of Mexico.

  19. Some conceptual designs for a LASSY spectrometer magnet

    International Nuclear Information System (INIS)

    Green, M.A.

    1995-09-01

    The LASSY spectrometer is a gas filled spectrometer (hydrogen or helium at a pressure of about 1 torr). The design bending power for the primary bending magnet for the spectrometer will have an induction bend radius product of 2.5 tesla-meters. In order to increase the acceptance of the spectrometer, the bending magnet system must be located close to the target where the desired nuclei are created. The spectrometer magnet system must consist of both bending and focusing elements so that the wide acceptance of particles can be brought to a focus at the analysis point that is down stream from the last magnet element. In order improve the spectrometer resolution and to catch the shortest lived nuclei, the length of the magnet system must be as short as possible. The length for the LASSY spectrometer magnet system from the target to the analysis point has been set at 2.5 meters or less. To improve the resolution of the spectrometer, the bending angle for bending magnet system must be increased to close to 180 degrees. In order to achieve a large bending angle and a short magnet system length, the bending induction must be above 3 tesla and the focusing elements must be combined with the bending elements. As a result, a LASSY spectrometer will have bending magnet with a bending angle from 140 to 170 degrees. This magnet win be combined with one or more focusing magnets (a straight dipole in some places and a combined function dipole in other places). The result is a single superconducting bending magnet with one or more quadrupoles incorporated within the large angle bending magnet

  20. Micro Plasma Spectrometer

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this IRAD project is to develop a preliminary design elements of miniature electron and ion plasma spectrometers and supporting electronics, focusing...

  1. Application of a portable total reflection x-ray fluorescence spectrometer to a trace elemental analysis of wines

    International Nuclear Information System (INIS)

    Kunimura, Shinsuke; Kawai, Jun

    2009-01-01

    A portable total reflection X-ray fluorescence (TXRF) spectrometer has been applied to a trace elemental analysis of wines. Sulfur, K, Mn, Fe, and Rb were detected. These five elements were quantified by using 1 ppm of Co as an internal standard. The quantified concentrations ranged from sub-ppm to several hundred ppm. Because of organic substances in wines, the scattering of the incident X-rays from the dry residues of wines becomes strong. Therefore, a high spectral background appears in TXRF spectra of wines. Because of this background, relative standard deviations of the quantified concentrations were from 4 to 28%. Although the high spectral background appeared in the TXRF spectra of the wines, a detection limit down to several tens of ppb was achieved. The present portable spectrometer can be applied to screening for trace elements in wines before an accurate and precise analysis using a large elemental analyzer. (author)

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

    International Nuclear Information System (INIS)

    Lindenbaum, S.J.

    1988-01-01

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

  3. Compact Spectrometers Based on Linear Variable Filters

    Data.gov (United States)

    National Aeronautics and Space Administration — Demonstrate a linear-variable spectrometer with an H2RG array. Linear Variable Filter (LVF) spectrometers provide attractive resource benefits – high optical...

  4. Incidence and significance of FLT3-ITD and NPM1 mutations in patients with normal karyotype acute myeloid leukaemia.

    LENUS (Irish Health Repository)

    Haslam, K

    2012-02-01

    BACKGROUND: Acute myeloid leukaemia (AML) is a heterogeneous clonal disorder of haematopoietic progenitor cells. Approximately half of all adult AML patients have a normal karyotype (NK-AML) and an intermediate risk prognosis. AIMS: To determine the incidence and prognostic significance of NPM1 and FLT3-ITD mutations in a population of patients with NK-AML. METHODS: FLT3-ITD and NPM1 mutation status was retrospectively sought in presentation samples from 44 NK-AML patients. RESULTS: FLT3-ITD and NPM1 mutations were detected in 45.5 and 54.5% of patients, respectively, allowing stratification according to genotype. CONCLUSIONS: FLT3-ITD and NPM1 mutation status can be defined in NK-AML. Prospective screening for these mutations is advocated in all NK-AML patients, as the genotype is of clinical importance when considering treatment options including stem cell transplantation.

  5. Practical using of TXRF spectrometers with slitless collimators for the trace analysis of targets surfaces

    International Nuclear Information System (INIS)

    Egorov, V.K.; Zuev, A.P.; Kondratiev, O.S.; Egorov, E.V.

    2000-01-01

    TXRF spectrometer with the slitless collimator used for a formation of the x-ray excitating beam (TXRF-SC spectrometer) is a new variety of an instrument been destined for the trace analysis of surfaces by x-ray fluorescence method at the total reflection of the x-ray incident beam. Some theoretical concepts are introduced for a characterization of the x-ray optics been unique to the TXRF-SC spectrometer. The principle design of the TXRF-SC spectrometer used for the trace quantitative analysis of a surface are discussed. Spectra of a secondary x-ray radiation yield for typical targets been collected by using of the TXRF-SC spectrometer and calculation of surface trace elements concentrations are presented. The analytical and operating parameters of the TXRF-SC spectrometer and one characterized by standard optical scheme are compared. The slitless collimator of the x-ray radiation is formed by two quartz polished plates mated together. Lengths of the plates are not equal. The target is placed on the surface of the long quartz plate and produces the continuation of the initial slitless collimator. Target orientation problem vanishes but problem of the surface contact effect appears. The secondary x-ray radiation excitated in a surface of the target is led out across the hole in the long quartz plate. The radiation is registered by a standard Si (Li) semiconductor detector and is collected by a multi-channel analyzer. The fundamental difference of the x-ray optical scheme been unique to TXRF-SC spectrometer from the standard one is the excitation of a studied surface by a flared x-ray beam with angle ΔΘ = 2Θ c , where Θ c is the critical angle of the total reflection. The vital peculiarity of a x-ray slitless collimation is the absence of a radiation monochromatism in output of the collimator. The sensible divergence of the x-ray excitating beam and the availability in it of monochromatic and white radiation alike allow to get in the surface layer of target the

  6. Experimental study of pion-nucleus elastic scattering above the Δ-resonance with the SKS spectrometer

    International Nuclear Information System (INIS)

    Takahashi, Toshiyuki

    1995-11-01

    Differential cross sections of the pion elastic scattering in the GeV/c region were systematically measured by using a newly constructed superconducting kaon spectrometer at KEK. The pion incident momenta were 610, 710, 790, and 895 MeV/c for 12 C(π - , π - ) 12 C and 790 MeV/c for 208 Pb(π ± , π ± ) 208 Pb. We have obtained the cross sections with absolute normalization uncertainty of about 10%. The π - -p scattering data measured with a CH target agree well with the phase-shift calculations, which confirms the accuracy of the absolute values of the cross sections. The angular distributions of the differential cross sections for 12 C were compared with calculations by a first-order optical potential model. The calculation reproduces the data at forward scattering-angle regions except at 610 MeV/c, although it underestimates at large-angle region. The present data at 790 MeV/c are in between the BNL data at 800 MeV/c and the calculation, although our data are consistent with the BNL data within their systematic errors. The incident momentum dependence of σ total , σ R , and σ elastic , which were extracted by fitting the angular distributions, is different from that of the calculation with free π-N elementary amplitudes. It is well explained by taking account of Fermi motion. The 208 Pb data are well reproduced by the optical potential model. The root mean square radius of the neutron distribution has been deduced from π + and π - elastic scattering for the first time. Although the result has a model ambiguity, it agrees with that deduced from the proton elastic scattering. It is, however, smaller than the prediction of the relativistic Hartree calculation. (author). 55 refs

  7. Spectrometer for neutron inelastic scattering investigations of microsamples

    International Nuclear Information System (INIS)

    Balagurov, A.M.; Kozlenko, D.P.; Platonov, S.L.; Savenko, B.N.; Glazkov, V.P.; Krasnikov, Yu.M.; Naumov, I.V.; Pukhov, A.V.; Somenkov, V.A.; Syrykh, G.F.

    1997-01-01

    A new neutron spectrometer for investigation of inelastic neutron scattering on polycrystal microsamples under high pressure in sapphire and diamond anvils cells is described. The spectrometer is operating at the IBR-2 pulsed reactor in JINR. Parameters and methodical peculiarities of the spectrometer and the examples of experimental studies are given. (author)

  8. Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser.

    Science.gov (United States)

    Zastrau, Ulf; Fletcher, Luke B; Förster, Eckhart; Galtier, Eric Ch; Gamboa, Eliseo; Glenzer, Siegfried H; Heimann, Philipp; Marschner, Heike; Nagler, Bob; Schropp, Andreas; Wehrhan, Ortrud; Lee, Hae Ja

    2014-09-01

    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E = 1.1 × 10(-4) and wave-number resolution of Δk/k = 3 × 10(-3), allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5 μm agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.

  9. Spectrometer gun

    Science.gov (United States)

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

    1985-01-01

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

  10. RITA: The reinvented triple axis spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mason, T.E. [Toronto Univ., ON (Canada). Dept. of Physics; Clausen, K.N.; Aeppli, G.; McMorrow, D.R.; Kjems, J.K. [Risoe National Lab., Roskilde (Denmark)

    1995-11-01

    Risoe National Laboratory was reported to be in the process of developing a new spectrometer design, RITA, based on the triple axis design. The spectrometer will attempt to incorporate more recent innovations such as multilayer supermirrors and microstrip proportional counters into a rethinking of the triple-axis spectrometer. By optimizing the beam optics, using supermirrors and extending the analyser to map regions of (Q, {omega}) space using an array of independently controllable pyrolytic graphite crystals focussed on an area detector, it was hoped that the efficiency of single-crystal inelastic experiments could be increased by as much as a factor of 20. 7 figs., 20 refs.

  11. Normal spectral emissivity measurement of molten copper using an electromagnetic levitator superimposed with a static magnetic field

    International Nuclear Information System (INIS)

    Kurosawa, Ryo; Inoue, Takamitsu; Baba, Yuya; Sugioka, Ken-ichi; Kubo, Masaki; Tsukada, Takao; Fukuyama, Hiroyuki

    2013-01-01

    The normal spectral emissivity of molten copper was determined in the wavelength range of 780–920 nm and in the temperature range of 1288–1678 K, by directly measuring the radiance emitted by an electromagnetically levitated molten copper droplet under a static magnetic field of 1.5 T. The spectrometer for radiance measurement was calibrated using the relation between the theoretical blackbody radiance from Planck's law and the light intensity of a quasi-blackbody radiation source measured using a spectrometer at a given temperature. As a result, the normal spectral emissivity of molten copper was determined as 0.075 ± 0.011 at a wavelength of 807 nm, and it was found that its temperature dependence is negligible in the entire measurement temperature range tested. In addition, the results of the normal spectral emissivity and its wavelength dependence were discussed, in comparison with those obtained using the Drude free-electron model. (paper)

  12. New optical scheme for differential measurements of diffraction reflection intensity on X-radiation sliding incidence

    International Nuclear Information System (INIS)

    Golovin, A.L.; Mas', E.T.

    1989-01-01

    An X-ray optical scheme for differential measurements of X-ray diffraction under sliding incidence conditions is proposed and an attachment design realizng this scheme, using standard equipment, is described. The main feature of the scheme is the following: collimation according to the Bragg angle is carried out for the reflected beam rather than the incident one. Goniometers can be used from DRON, TRS, GS-5 and other spectrometers. The goniometer head carrying the sample is standard, it is a part of the DRON, TRS and DTS. The crystal analyzer is fixed on the attachment. The angular position of the crystal monochromator is controlled by an inductive sensor. The experimental differential curves of X-ray diffraction under conditions of sliding incidence, taken for a silicon crystal having the 111 orientation, are given as well

  13. A computer programme to monitor the performance of an X-ray fluorescence spectrometer

    International Nuclear Information System (INIS)

    Simpolo, G.F.

    1985-01-01

    A BASIC computer programme has been developed that measures the long- and short-term stability of an X-ray spectrometer and operational errors (and compares them with the limits specified by the manufacturer) and the dead time of the associated detectors. The programme also carries out checks on the spectrometer with regard to the performance of different combinations of the crystals, the detectors, the collimators, the sin 2 THETA angles, the apertures, the tracking of the sin 2 THETA amplifier, the operation of the second-order spectrum circuits, the operation of the automatic pulse-height analyser, the condition of the detectors, the condition of the X-ray tube, spectral contamination by the tube spectrum, and physical contamination by analytical specimens. Although the measurements take 15 hours, there is no disruption to normal, routine laboratory work since the measurements can be made automatically after routine work has been completed. Only four sample positions are required for this monitoring programme

  14. High resolution 14 MeV neutron spectrometer

    International Nuclear Information System (INIS)

    Pillon, M.

    1986-01-01

    A neutron spectrometer, based both on the track position identification and the energy measurement of recoiling protons from a hydrogenous radiator is proposed. The expected performance limits of this spectrometer with regard to energy resolution (deltaE/E), efficiency (epsilon) and counting rate are evaluated in five different configurations. The results show the possibility of deriving an optimized spectrometer design for applications on large fusion devices such as JET and NET with an energy resolution up 1% at 14 MeV

  15. Combining counts and incidence data: an efficient approach for estimating the log-normal species abundance distribution and diversity indices.

    Science.gov (United States)

    Bellier, Edwige; Grøtan, Vidar; Engen, Steinar; Schartau, Ann Kristin; Diserud, Ola H; Finstad, Anders G

    2012-10-01

    Obtaining accurate estimates of diversity indices is difficult because the number of species encountered in a sample increases with sampling intensity. We introduce a novel method that requires that the presence of species in a sample to be assessed while the counts of the number of individuals per species are only required for just a small part of the sample. To account for species included as incidence data in the species abundance distribution, we modify the likelihood function of the classical Poisson log-normal distribution. Using simulated community assemblages, we contrast diversity estimates based on a community sample, a subsample randomly extracted from the community sample, and a mixture sample where incidence data are added to a subsample. We show that the mixture sampling approach provides more accurate estimates than the subsample and at little extra cost. Diversity indices estimated from a freshwater zooplankton community sampled using the mixture approach show the same pattern of results as the simulation study. Our method efficiently increases the accuracy of diversity estimates and comprehension of the left tail of the species abundance distribution. We show how to choose the scale of sample size needed for a compromise between information gained, accuracy of the estimates and cost expended when assessing biological diversity. The sample size estimates are obtained from key community characteristics, such as the expected number of species in the community, the expected number of individuals in a sample and the evenness of the community.

  16. RADIO-FREQUENCY MASS SPECTROMETERS AND THEIR APPLICATIONS IN SPACE

    Energy Technology Data Exchange (ETDEWEB)

    Gilmour, Jr., A. S.

    1963-08-15

    The operation of three common radio-frequency mass spectrometers is described, and their performances are compared. Their limitations are pointed out. It is concluded that the quadrupole spectrometer has fewer limitations and is more generally useful in space probes than the other devices. Some present and proposed uses of spectrometers in space are discussed, and the problem of contamination of the atmosphere being sampled by the spectrometer is reviewed. (auth)

  17. The portable micro-computerized multichannel spectrometer for geological application

    International Nuclear Information System (INIS)

    Fang Fang; Jia Wenyi; Zou Rongsheng; Ma Yingjie; Zhou Jianbin

    1999-01-01

    The portable micro-computerized multichannel spectrometer is based on the book computer and employs the A/D integrated circuit with 12 bits. It is a 2048 channel spectrometer which is consisted of hardware and software. The author analyzed the hardware circuit and software construction of the micro-computerized multichannel spectrometer which is suitable for filed geological application. The main technical specifications and application of the new multichannel spectrometer were also discussed

  18. The portable micro-computerized multichannel spectrometer for geological application

    International Nuclear Information System (INIS)

    Fang Fang; Jia Wenyi; Zhou Rongsheng; Ma Yingjie; Zhou Jianbin

    1999-01-01

    The portable micro-computerized multichannel spectrometer is based on the book computer and employs the A/D integrated circuit with 12 bits. It is a 2048 channel spectrometer which consists of hardware and software. The author analyzed the hardware circuit and software construction of the micro-computerized multichannel spectrometer which is suitable for field geological application. The main technical specifications and application of the new multichannel spectrometer were also discussed

  19. Thermal self-focusing at oblique incidence

    International Nuclear Information System (INIS)

    Craxton, R.S.; McCrory, R.L.

    1984-03-01

    Thermal self-focusing at oblique incidence has been investigated in two-dimensional line-focus geometry using the Eulerian hydrodynamics simulation code SAGE. The laser beam interacts with a long-scale-length preformed plasma with an expontial density profiele. Questions to be addressed include: (1) What happens when a self-focusing channel reaches the turning point of the incident rays, and (2) Does the unabsorbed light return in the specular direction or back along the channel. A comparison is also made between thermal self-focusing at normal incidence in cylindrical and line-focus geometries: in cylindrical geometry the self-focusing mechanism is enhanced by the relative ease with which plasma may be expelled from a small cylindrical channel

  20. Artificial intelligence for geologic mapping with imaging spectrometers

    Science.gov (United States)

    Kruse, F. A.

    1993-01-01

    This project was a three year study at the Center for the Study of Earth from Space (CSES) within the Cooperative Institute for Research in Environmental Science (CIRES) at the University of Colorado, Boulder. The goal of this research was to develop an expert system to allow automated identification of geologic materials based on their spectral characteristics in imaging spectrometer data such as the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). This requirement was dictated by the volume of data produced by imaging spectrometers, which prohibits manual analysis. The research described is based on the development of automated techniques for analysis of imaging spectrometer data that emulate the analytical processes used by a human observer. The research tested the feasibility of such an approach, implemented an operational system, and tested the validity of the results for selected imaging spectrometer data sets.

  1. Extended incident-angle dependence formula of sputter yield

    International Nuclear Information System (INIS)

    Ono, T.; Shibata, K.; Muramoto, T.; Kenmotsu, T.; Li Z.; Kawamura, T.

    2006-06-01

    We extend a new semi-empirical formula for incident-angle dependence of normalized sputter yield that includes the contribution to sputter yield from the direct knock-out process that was not considered in the previously proposed one. Three parameters included in the new one are estimated for data calculated with ACAT code for D + ions incident obliquely on C, Fe and W materials in incident-energy regions from several tens of eV to 10 keV. Then, the parameters are expressed with functions of incident energy. The formula with the functions derived well reproduces that using the ACAT data in the whole energy range. (author)

  2. Polarized epithermal neutron spectrometer at KENS

    International Nuclear Information System (INIS)

    Kohgi, M.

    1983-01-01

    A spectrometer employing a white, epithermal, polarized neutron beam is under construction at KENS. The neutron polarization is achieved by passage through a dynamically polarized proton filter (DPPF). The results of the test experiments show that the DPPF method is promising in obtaining polarized epithermal neutron beam. The basic design of the spectrometer is described

  3. Fast-response personal Moessbauer spectrometer

    International Nuclear Information System (INIS)

    Kholmetskij, A.L.; Mashlan, M.; Misevich, O.V.; Evdokimov, V.A.; Lopatik, A.R.; Zhak, D.; Fedorov, A.A.; Snashel, V.

    1995-01-01

    Spectrometer design to record transmission Moessbauer spectra is described. The spectrometer consists of PC/AT computer with 1 mb memory and 40 mb hard disk, of EPSON LX 850 printer, of color monitor with VGA graphical adapter, of data accumulation system, of speed generator, of motion system with minivibrator, of scintillation detector with YA10 3 :Ce scintillator, of single-channel amplitude analyzer, of measuring bench and of 57 Co(Rh) source. 1 ref.; 1 fig

  4. The BTeV main spectrometer

    International Nuclear Information System (INIS)

    Sheldon, P.D.

    2001-01-01

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

  5. Miniature neutron-alpha activation spectrometer

    International Nuclear Information System (INIS)

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

    2002-01-01

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

  6. [Research of dual-photoelastic-modulator-based beat frequency modulation and Fourier-Bessel transform imaging spectrometer].

    Science.gov (United States)

    Wang, Zhi-Bin; Zhang, Rui; Wang, Yao-Li; Huang, Yan-Fei; Chen, You-Hua; Wang, Li-Fu; Yang, Qiang

    2014-02-01

    As the existing photoelastic-modulator(PEM) modulating frequency in the tens of kHz to hundreds of kHz between, leading to frequency of modulated interference signal is higher, so ordinary array detector cannot effectively caprure interference signal..A new beat frequency modulation method based on dual-photoelastic-modulator (Dual-PEM) and Fourier-Bessel transform is proposed as an key component of dual-photoelastic-modulator-based imaging spectrometer (Dual-PEM-IS) combined with charge coupled device (CCD). The dual-PEM are operated as an electro-optic circular retardance modulator, Operating the PEMs at slightly different resonant frequencies w1 and w2 respectively, generates a differential signal at a much lower heterodyne frequency that modulates the incident light. This method not only retains the advantages of the existing PEM, but also the frequency of modulated photocurrent decreased by 2-3 orders of magnitude (10-500 Hz) and can be detected by common array detector, and the incident light spectra can be obtained by Fourier-Bessel transform of low frequency component in the modulated signal. The method makes the PEM has the dual capability of imaging and spectral measurement. The basic principle is introduced, the basic equations is derived, and the feasibility is verified through the corresponding numerical simulation and experiment. This method has' potential applications in imaging spectrometer technology, and analysis of the effect of deviation of the optical path difference. This work provides the necessary theoretical basis for remote sensing of new Dual-PEM-IS and for engineering implementation of spectra inversion.

  7. The LASS [Larger Aperture Superconducting Solenoid] spectrometer

    International Nuclear Information System (INIS)

    Aston, D.; Awaji, N.; Barnett, B.

    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

  8. The LASS (Larger Aperture Superconducting Solenoid) spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Optimization of time-correlated single photon counting spectrometer

    International Nuclear Information System (INIS)

    Zhang Xiufeng; Du Haiying; Sun Jinsheng

    2011-01-01

    The paper proposes a performance improving scheme for the conventional time-correlated single photon counting spectrometer and develops a high speed data acquisition card based on PCI bus and FPGA technologies. The card is used to replace the multi-channel analyzer to improve the capability and decrease the volume of the spectrometer. The process of operation is introduced along with the integration of the spectrometer system. Many standard samples are measured. The experimental results show that the sensitivity of the spectrometer is single photon counting, and the time resolution of fluorescence lifetime measurement can be picosecond level. The instrument could measure the time-resolved spectroscopy. (authors)

  10. Development of triple axis neutron spectrometer (Paper No. 24)

    International Nuclear Information System (INIS)

    Pal, B.C.; Wadhwa, N.R.; Goveas, S.H.

    1987-02-01

    The triple axis neutron spectrometers are the basic instruments intended for use with neutron beams from reactors. Various types of spectrometers, each devoted to different kinds of measurement can be designed and manufactured, once a prototype having all the attributes of a versatile instrument is designed and developed. With the view to achieving self reliance in this field, Central Workshops of Bhabha Atomic Research Centre (BARC), Bombay designed and developed a prototype of triple axis spectrometer meeting the specifications prepared by Nuclear Physics Division of BARC . This spectrometer, with a moving wedge system was successfully manufactured and installed at 'DHRUVA'. Another version of this spectrometer, called the 'Polarised Neutron Spectrometer' was also built and exported to South Korea and installed at Korea Advanced Energy Research Institute, Seoul. This paper deals with basic concept, development of design, engineering of mechanical assemblies, the manufacturing approach and problems encountered during manufacture. (author). 3 figs

  11. Oblique incidence of electron beams - comparisons between calculated and measured dose distributions

    International Nuclear Information System (INIS)

    Karcher, J.; Paulsen, F.; Christ, G.

    2005-01-01

    Clinical applications of high-energy electron beams, for example for the irradiation of internal mammary lymph nodes, can lead to oblique incidence of the beams. It is well known that oblique incidence of electron beams can alter the depth dose distribution as well as the specific dose per monitor unit. The dose per monitor unit is the absorbed dose in a point of interest of a beam, which is reached with a specific dose monitor value (DIN 6814-8[5]). Dose distribution and dose per monitor unit at oblique incidence were measured with a small-volume thimble chamber in a water phantom, and compared to both normal incidence and calculations of the Helax TMS 6.1 treatment planning system. At 4 MeV and 60 degrees, the maximum measured dose per monitor unit at oblique incidence was decreased up to 11%, whereas at 18MeV and 60 degrees this was increased up to 15% compared to normal incidence. Comparisons of measured and calculated dose distributions showed that the predicted dose at shallow depths is usually higher than the measured one, whereas it is smaller at depths beyond the depth of maximum dose. On the basis of the results of these comparisons, normalization depths and correction factors for the dose monitor value were suggested to correct the calculations of the dose per monitor unit. (orig.)

  12. Scintillation forward spectrometer of the SPHERE setup

    International Nuclear Information System (INIS)

    Anisimov, Yu.S.; Afanas'ev, S.V.; Bondarev, V.K.

    1991-01-01

    The construction of the forward spectrometer for the 4π SPHERE setup to study multiple production of particles in nucleus-nucleus interactions is described. The measured parameters of the spectrometer detectors are presented. 7 refs.; 14 figs.; 1 tab

  13. Multiplate ionization total absorption spectrometer with a compressed gas

    International Nuclear Information System (INIS)

    Baskakov, V.I.; Dolgoshein, B.A.; Kantserov, V.A.

    1978-01-01

    The characteristics of a multiplate total absorption spectrometer working with the compressed xenon (up to 25 atm) containing up to 23 radiation lengths of matter are studied. The dependence of the spectrometer energy resolution on the detecting matter density, on the material and thickness of the absorber plates has been studied. The ability of the spectrometer with a tungsten absorber to select hadrons and electrons with P=6 GeV/c by total energy release and characteristics of the cascade longitudinal development has been also studied. The gas spectrometer as it is shown differs quite slightly from the similar spectrometer with liquid argon as for its time resolution it is much better

  14. Effect of front and rear incident proton irradiation on silicon solar cells

    Science.gov (United States)

    Anspaugh, Bruce; Kachare, Ram

    1987-01-01

    Four solar cell types of current manufacture were irradiated through the front and rear surfaces with protons in the energy range between 1 and 10 MeV. The solar cell parameters varied for this study were cell thickness and back surface field (BSF) vs. no BSF. Some cells were irradiated at normal incidence and an equal number were irradiated with simulated isotropic fluences. The solar cell electrical characteristics were measured under simulated AM0 illumination after each fluence. Using the normal incidence data, proton damage coefficients were computed for all four types of cells for both normal and omnidirectional radiation fields. These were found to compare well with the omnidirectional damage coefficients derived directly from the rear-incidence radiation data. Similarly, the rear-incidence omnidirectional radiation data were used to compute appropriate damage coefficients. A method for calculating the effect of a spectrum of energies is derived from these calculations. It is suitable for calculating the degradation of cells in space when they have minimal rear-surface shielding.

  15. An isodose shift technique for obliquely incident electron beams

    International Nuclear Information System (INIS)

    Ulin, K.; Sternick, E.S.

    1989-01-01

    It is well known that when an electron beam is incident obliquely on the surface of a phantom, the depth dose curve measured normal to the surface is shifted toward the surface. Based on geometrical arguments alone, the depth of the nth isodose line for an electron beam incident at an angle θ should be equal to the product of cos θ and the depth of the nth isodose line at normal incidence. This method, however, ignores the effects of scatter and can lead to significant errors in isodose placement for beams at large angles of incidence. A semi-empirical functional relationship and a table of isodose shift factors have been developed with which one may easily calculate the depth of any isodose line for beams at incident angles of 0 degree to 60 degree. The isodose shift factors are tabulated in terms of beam energy (6--22 MeV) and isodose line (10%--90%) and are shown to be relatively independent of beam size and incident angle for angles <60 degree. Extensive measurements have been made on a Varian Clinac 2500 linear accelerator with a parallel-plate chamber and polystyrene phantom. The dependence of the chamber response on beam angulation has been checked, and the scaling factor of the polystyrene phantom has been determined to be equal to 1.00

  16. Mini ion trap mass spectrometer

    Science.gov (United States)

    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.

  17. Normalization of satellite imagery

    Science.gov (United States)

    Kim, Hongsuk H.; Elman, Gregory C.

    1990-01-01

    Sets of Thematic Mapper (TM) imagery taken over the Washington, DC metropolitan area during the months of November, March and May were converted into a form of ground reflectance imagery. This conversion was accomplished by adjusting the incident sunlight and view angles and by applying a pixel-by-pixel correction for atmospheric effects. Seasonal color changes of the area can be better observed when such normalization is applied to space imagery taken in time series. In normalized imagery, the grey scale depicts variations in surface reflectance and tonal signature of multi-band color imagery can be directly interpreted for quantitative information of the target.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Polarized neutron spectrometer for inelastic experiments at J-PARC

    Directory of Open Access Journals (Sweden)

    Yokoo Tetsuya

    2015-01-01

    Full Text Available Construction of the newly developed polarization analysis neutron chopper spectrometer (POLANO commenced in the Japan Proton Accelerator Research Complex (J-PARC, Materials and Life Science Experimental Facility (MLF. The POLANO is a direct geometry chopper spectrometer with neutron polarization analysis capability. In the suite of inelastic spectrometers, six instruments are now in operation. POLANO will be the only spectrometer dedicated to polarization analysis experiments. The primary phase of the construction will be completed by 2014 with beam commissioning scheduled for 2015.

  20. Performance Studies of Resistive Micromegas Detectors for the Upgrade of the ATLAS Muon Spectrometer

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00387450

    2017-01-01

    With the high luminosity upgrade of the LHC the ATLAS Muon spectrometer will face increased particle rates, requiring an upgrade of the innermost end-cap detectors with a high-rate capable technology. Micromegas have been chosen as main tracking technology for this New Small Wheel upgrade. In an intense R$\\&$D and prototype phase the technology has proven to meet the stringent performance requirements of highly efficient particle detection with better than 100$\\rm{\\mu m}$ spatial resolution, independent of the track incidence angle up to 32$^\\circ$, in a magnetic field B $\\leq$ 0.3 T and at background hit rate of up to 15kHz/cm$^2$.

  1. Quantitative survey radiographic evaluation of the lumbosacral spine of normal dogs and dogs with degenerative lumbosacral stenosis

    International Nuclear Information System (INIS)

    Mattoon, J.S.; Koblik, P.D.

    1993-01-01

    Survey radiographic studies of the lumbosacral region for 93 normal dogs and for 26 dogs with confirmed degenerative lumbosacral stenosis were reviewed. Normal dogs were divided into 9 groups based on age and body weight. For normal dogs, increasing age and body weight were associated with a decreased ability to extend the lumbosacral joint and with increased incidence and severity of spondylosis. Transitional lumbosacral vertebrae and evidence of lumbosacral disc space collapse were very infrequent findings, and the pivot point for lumbosacral motion was consistently centered over the lumbosacral disc space. Relative to an age/weight matched sub-population of normal dogs, dogs with degenerative lumbosacral stenosis had similar mean normalized lumbosacral vertebral canal height, larger mean neutral lumbosacral angle, decreased extension of the lumbosacral joint, increased flexion of the lumbosacral joint, reduced lumbosacral range of motion, increased lumbosacral dynamic malalignment, higher incidence and severity of spondylosis, higher incidence of transitional vertebrae, and higher incidence of lumbosacral disc space collapse. A logistic model based strictly on radiographic parameters was able to discriminate normal from affected dogs with an overall accuracy rate of 86%

  2. The Spectrometer

    Science.gov (United States)

    Greenslade, Thomas B., Jr.

    2012-01-01

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

  3. The MIRI Medium Resolution Spectrometer calibration pipeline

    NARCIS (Netherlands)

    Labiano, A.; Azzollini, R.; Bailey, J.; Beard, S.; Dicken, D.; García-Marín, M.; Geers, V.; Glasse, A.; Glauser, A.; Gordon, K.; Justtanont, K.; Klaassen, P.; Lahuis, F.; Law, D.; Morrison, J.; Müller, M.; Rieke, G.; Vandenbussche, B.; Wright, G.

    2016-01-01

    The Mid-Infrared Instrument (MIRI) Medium Resolution Spectrometer (MRS) is the only mid-IR Integral Field Spectrometer on board James Webb Space Telescope. The complexity of the MRS requires a very specialized pipeline, with some specific steps not present in other pipelines of JWST instruments,

  4. Use of UAV-Borne Spectrometer for Land Cover Classification

    Directory of Open Access Journals (Sweden)

    Sowmya Natesan

    2018-04-01

    Full Text Available Unmanned aerial vehicles (UAV are being used for low altitude remote sensing for thematic land classification using visible light and multi-spectral sensors. The objective of this work was to investigate the use of UAV equipped with a compact spectrometer for land cover classification. The UAV platform used was a DJI Flamewheel F550 hexacopter equipped with GPS and Inertial Measurement Unit (IMU navigation sensors, and a Raspberry Pi processor and camera module. The spectrometer used was the FLAME-NIR, a near-infrared spectrometer for hyperspectral measurements. RGB images and spectrometer data were captured simultaneously. As spectrometer data do not provide continuous terrain coverage, the locations of their ground elliptical footprints were determined from the bundle adjustment solution of the captured images. For each of the spectrometer ground ellipses, the land cover signature at the footprint location was determined to enable the characterization, identification, and classification of land cover elements. To attain a continuous land cover classification map, spatial interpolation was carried out from the irregularly distributed labeled spectrometer points. The accuracy of the classification was assessed using spatial intersection with the object-based image classification performed using the RGB images. Results show that in homogeneous land cover, like water, the accuracy of classification is 78% and in mixed classes, like grass, trees and manmade features, the average accuracy is 50%, thus, indicating the contribution of hyperspectral measurements of low altitude UAV-borne spectrometers to improve land cover classification.

  5. High intensity TOF spectrometer for cold neutrons

    International Nuclear Information System (INIS)

    Maayouf, R.M.; Abd El-Kawy, A.; Habib, N.; Adib, M.; Hamouda, I.

    1984-01-01

    This work presents a neutron time-of-flight (TOF) spectrometer developed specially for total neutron cross-section measurements at neutron energies below 5 MeV and sample's temperature varying from the liquid nitrogen one and up to 500 0 K. The spectrometer is equipped by remote control unit, designed especially, in order to move the sample in and out of the beam during the experimental measurements. The spectrometer has proved to be useful for transmission measurements at neutron energies below 5 MeV. It has a reasonable energy resolution (4.4%) and high effect to background ratio (11.1) at 5 MeV

  6. The Omega spectrometer

    CERN Multimedia

    1972-01-01

    The Omega spectrometer which came into action during the year. An array of optical spark chambers can be seen withdrawn from the magnet aperture. In the 'igloo' above the magnet is located the Plumbicon camera system which collects information from the spark chambers.

  7. Silicon spectrometer with a Peltier refrigerator

    International Nuclear Information System (INIS)

    Belcarz, E.; Chwaszczewska, J.; Hahn, G.; Nowicki, W.; Sawicka, B.; Skoczek, K.; Slapa, M.; Szymczak, M.

    1974-01-01

    This paper describes a spectrometer with a Si(Li) detector cooled by a Peltier refrigerator. The spectrometer is able to analyse samples of practically all most frequently encountered emitters of alpha, beta and low energy gamma radiation. The energy resolution were about 1.3-1.5 keV for 14 keV gamma radiation. The system can also operate in field conditions in the fluorescence analysis. (author)

  8. Responsivity calibration of the extreme ultraviolet spectrometer in the range of 175-435 Å

    Directory of Open Access Journals (Sweden)

    B. Tu

    2017-04-01

    Full Text Available We reported the relative responsivity calibration of the grazing-incidence flat-field EUV spectrometer between 175 and 435 Å by means of two methods. The first method is implemented by measuring the diffraction efficiency of the grating with synchrotron radiation light source. Considering the transmission efficiency and quantum efficiency of the other optical components in the spectrometer, the total responsivity was then obtained. The second one was carried out by measuring line emissions from C3+, N4+ and O3+ ions at Shanghai high temperature super conductor electron beam ion trap (SH-HtscEBIT. The EUV spectra were also simulated theoretically via a collisional radiative model. In the calculation, the second-order relativistic many-body perturbation theory approach based on the flexible atomic code was used to calculate the energy levels and transition rates; the close-coupling R-matrix approach and relativistic distorted wave method were utilized to calculate the collision strength of electron impact excitation. In comparison with the spectroscopic measurements at EBIT device, the differences between the measured and simulated relative line intensities were obtained. The responsivity calibration for the spectrometer was then achieved by a 3rd degree polynomial function fitting. Our measurement shows that the responsivity between 175 and 435 Å varies by factor of ∼ 46. The two results of calibration demonstrated a consistency within an average deviation of 24%. In addition, an evaluation of our calculations on C iv, N v and O iv line emissions in this wavelength region was given.

  9. Normalization Methods and Selection Strategies for Reference Materials in Stable Isotope Analyes. Review

    Energy Technology Data Exchange (ETDEWEB)

    Skrzypek, G. [West Australian Biogeochemistry Centre, John de Laeter Centre of Mass Spectrometry, School of Plant Biology, University of Western Australia, Crawley (Australia); Sadler, R. [School of Agricultural and Resource Economics, University of Western Australia, Crawley (Australia); Paul, D. [Department of Civil Engineering (Geosciences), Indian Institute of Technology Kanpur, Kanpur (India); Forizs, I. [Institute for Geochemical Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-07-15

    Stable isotope ratio mass spectrometers are highly precise, but not accurate instruments. Therefore, results have to be normalized to one of the isotope scales (e.g., VSMOW, VPDB) based on well calibrated reference materials. The selection of reference materials, numbers of replicates, {delta}-values of these reference materials and normalization technique have been identified as crucial in determining the uncertainty associated with the final results. The most common normalization techniques and reference materials have been tested using both Monte Carlo simulations and laboratory experiments to investigate aspects of error propagation during the normalization of isotope data. The range of observed differences justifies the need to employ the same sets of standards worldwide for each element and each stable isotope analytical technique. (author)

  10. Development of Neutron Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hee; Lee, J. S.; Seong, B. S. (and others)

    2007-06-15

    Neutron spectrometers which are used in the basic researches such as physics, chemistry and materials science and applied in the industry were developed at the horizontal beam port of HANARO reactor. In addition, the development of core components for neutron scattering and the upgrade of existing facilities are also performed. The vertical neutron reflectometer was fabricated and installed at ST3 beam port. The performance test of the reflectometer was completed and the reflectometer was opened to users. The several core parts and options were added in the polarized neutron spectrometer. The horizontal neutron reflectometer from Brookhaven National Laboratory was moved to HANARO and installed, and the performance of the reflectometer was examined. The HIPD was developed and the performance test was completed. The base shielding for TAS was fabricated. The soller collimator, Cu mosaic monochromator, Si BPC monochromator and position sensitive detector were developed and applied in the neutron spectrometer as part of core component development activities. In addition, the sputtering machine for mirror device are fabricated and the neutron mirror is made using the sputtering machine. The FCD was upgraded and the performance of the FCD are improved over the factor of 10. The integration and upgrade of the neutron detection system were also performed.

  11. The influence of incident beam's angle offset of Fourier transform infrared spectrometer on the spectrum measurement explored with synchrotron radiation

    International Nuclear Information System (INIS)

    Chen Wenhao; Chen Min; Xiao Tiqiao

    2011-01-01

    Effects of the incident angle offset on FT-IR spectra are investigated in this paper. The simulated FT-IR spectra are obtained by Fourier inverse transform. The results show that this frequency shift varies with the angle offset of the incident beam in FT-IR. As an example,the factors that affect the angle of incident IR light at SSRF are analyzed. According to performance specifications of the IR beamline, requirements of the optical component installation precision and position drift of the light source are given. (authors)

  12. ISLA: An Isochronous Spectrometer with Large Acceptances

    Energy Technology Data Exchange (ETDEWEB)

    Bazin, D., E-mail: bazin@nscl.msu.edu; Mittig, W.

    2013-12-15

    A novel type of recoil mass spectrometer and separator is proposed for the future secondary radioactive beams of the ReA12 accelerator at NSCL/FRIB, inspired from the TOFI spectrometer developed at the Los Alamos National Laboratory for online mass measurements. The Isochronous Spectrometer with Large Acceptances (ISLA) is able to achieve superior characteristics without the compromises that usually plague the design of large acceptance spectrometers. ISLA can provide mass-to-charge ratio (m/q) measurements to better than 1 part in 1000 by using an optically isochronous time-of-flight independent of the momentum vector of the recoiling ions, despite large acceptances of 20% in momentum and 64 msr in solid angle. The characteristics of this unique design are shown, including requirements for auxiliary detectors around the target and the various types of reactions to be used with the re-accelerated radioactive beams of the future ReA12 accelerator.

  13. Multichannel Dynamic Fourier-Transform IR Spectrometer

    Science.gov (United States)

    Balashov, A. A.; Vaguine, V. A.; Golyak, Il. S.; Morozov, A. N.; Khorokhorin, A. I.

    2017-09-01

    A design of a multichannel continuous scan Fourier-transform IR spectrometer for simultaneous recording and analysis of the spectral characteristics of several objects is proposed. For implementing the design, a multi-probe fiber is used, constructed from several optical fibers connected into a single optical connector and attached at the output of the interferometer. The Fourier-transform spectrometer is used as a signal modulator. Each fiber is individually mated with an investigated sample and a dedicated radiation detector. For the developed system, the radiation intensity of the spectrometer is calculated from the condition of the minimum spectral resolution and parameters of the optical fibers. Using the proposed design, emission spectra of a gas-discharge neon lamp have been recorded using a single fiber 1 mm in diameter with a numerical aperture NA = 0.22.

  14. Performance improvement of two-dimensional EUV spectroscopy based on high frame rate CCD and signal normalization method

    International Nuclear Information System (INIS)

    Zhang, H.M.; Morita, S.; Ohishi, T.; Goto, M.; Huang, X.L.

    2014-01-01

    In the Large Helical Device (LHD), the performance of two-dimensional (2-D) extreme ultraviolet (EUV) spectroscopy with wavelength range of 30-650A has been improved by installing a high frame rate CCD and applying a signal intensity normalization method. With upgraded 2-D space-resolved EUV spectrometer, measurement of 2-D impurity emission profiles with high horizontal resolution is possible in high-density NBI discharges. The variation in intensities of EUV emission among a few discharges is significantly reduced by normalizing the signal to the spectral intensity from EUV_—Long spectrometer which works as an impurity monitor with high-time resolution. As a result, high resolution 2-D intensity distribution has been obtained from CIV (384.176A), CV(2x40.27A), CVI(2x33.73A) and HeII(303.78A). (author)

  15. The high-resolution time-of-flight spectrometer TOFTOF

    Energy Technology Data Exchange (ETDEWEB)

    Unruh, Tobias [Technische Universitaet Muenchen, Forschungsneutronenquelle Heinz Maier-Leibnitz FRM II and Physik Department E13, Lichtenbergstr. 1, 85747 Garching (Germany)], E-mail: Tobias.Unruh@frm2.tum.de; Neuhaus, Juergen; Petry, Winfried [Technische Universitaet Muenchen, Forschungsneutronenquelle Heinz Maier-Leibnitz FRM II and Physik Department E13, Lichtenbergstr. 1, 85747 Garching (Germany)

    2007-10-11

    The TOFTOF spectrometer is a multi-disc chopper time-of-flight spectrometer for cold neutrons at the research neutron source Heinz Maier-Leibnitz (FRM II). After five reactor cycles of routine operation the characteristics of the instrument are reported in this article. The spectrometer features an excellent signal to background ratio due to its remote position in the neutron guide hall, an elaborated shielding concept and an s-shaped curved primary neutron guide which acts i.a. as a neutron velocity filter. The spectrometer is fed with neutrons from the undermoderated cold neutron source of the FRM II leading to a total neutron flux of {approx}10{sup 10}n/cm{sup 2}/s in the continuous white beam at the sample position distributed over a continuous and particularly broad wavelength spectrum. A high energy resolution is achieved by the use of high speed chopper discs made of carbon-fiber-reinforced plastic. In the combination of intensity, resolution and signal to background ratio the spectrometer offers new scientific prospects in the fields of inelastic and quasielastic neutron scattering.

  16. The high-resolution time-of-flight spectrometer TOFTOF

    Science.gov (United States)

    Unruh, Tobias; Neuhaus, Jürgen; Petry, Winfried

    2007-10-01

    The TOFTOF spectrometer is a multi-disc chopper time-of-flight spectrometer for cold neutrons at the research neutron source Heinz Maier-Leibnitz (FRM II). After five reactor cycles of routine operation the characteristics of the instrument are reported in this article. The spectrometer features an excellent signal to background ratio due to its remote position in the neutron guide hall, an elaborated shielding concept and an s-shaped curved primary neutron guide which acts i.a. as a neutron velocity filter. The spectrometer is fed with neutrons from the undermoderated cold neutron source of the FRM II leading to a total neutron flux of ˜1010n/cm2/s in the continuous white beam at the sample position distributed over a continuous and particularly broad wavelength spectrum. A high energy resolution is achieved by the use of high speed chopper discs made of carbon-fiber-reinforced plastic. In the combination of intensity, resolution and signal to background ratio the spectrometer offers new scientific prospects in the fields of inelastic and quasielastic neutron scattering.

  17. Dependence of the solar absorptance of selective absorber coatings on the angle of incidence

    Energy Technology Data Exchange (ETDEWEB)

    Reed, K A

    1977-01-01

    The directional solar absorptances ..cap alpha../sub s/(theta) of samples of a number of selective absorber coatings have been determined. The spectral directional hemispherical reflectances plambda(theta;2..pi..) of each sample was measured over the wavelength range 0.3..mu.. to 2.5..mu.. at angles of incidence theta between 10/sup 0/ and 80/sup 0/. The quantity (1-plambda(theta;2..pi..)) was convoluted over an AM2 solar spectrum to obtain ..cap alpha../sub s/(theta) at each angle of incidence. The solar absorptance at near normal incidence varied from sample to sample and from coating to coating, as expected, given the present state of the art. All the absorptances show similar angular dependences, however. When normalized to unity at normal incidence, the data nearly describe a single curve, for which a power series in theta was found. For comparison, the solar absorptance was also determined for freshly prepared lamp black.

  18. Frequency-Modulation Correlation Spectrometer

    Science.gov (United States)

    Margolis, J. S.; Martonchik, J. V.

    1985-01-01

    New type of correlation spectrometer eliminates need to shift between two cells, one empty and one containing reference gas. Electrooptical phase modulator sinusoidally shift frequencies of sample transmission spectrum.

  19. High intensity line source for x-ray spectrometer calibration

    International Nuclear Information System (INIS)

    Thoe, R.S.

    1986-06-01

    A high intensity electron-impact x-ray source using a one-dimensional Pierce lens has been built for the purpose of calibrating a bent crystal x-ray spectrometer. This source focuses up to 100 mA of 20-keV electrons to a line on a liquid-cooled anode. The line (which can serve as a virtual slit for the spectrometer) measures approximately 800 μ x 2 cm. The source is portable and therefore adaptable to numerous types of spectrometer applications. One particular application, the calibration of a high resolution (r = 10 4 ) time-resolved cyrstal spectrometer, will be discussed in detail

  20. Incident Duration Modeling Using Flexible Parametric Hazard-Based Models

    Directory of Open Access Journals (Sweden)

    Ruimin Li

    2014-01-01

    Full Text Available Assessing and prioritizing the duration time and effects of traffic incidents on major roads present significant challenges for road network managers. This study examines the effect of numerous factors associated with various types of incidents on their duration and proposes an incident duration prediction model. Several parametric accelerated failure time hazard-based models were examined, including Weibull, log-logistic, log-normal, and generalized gamma, as well as all models with gamma heterogeneity and flexible parametric hazard-based models with freedom ranging from one to ten, by analyzing a traffic incident dataset obtained from the Incident Reporting and Dispatching System in Beijing in 2008. Results show that different factors significantly affect different incident time phases, whose best distributions were diverse. Given the best hazard-based models of each incident time phase, the prediction result can be reasonable for most incidents. The results of this study can aid traffic incident management agencies not only in implementing strategies that would reduce incident duration, and thus reduce congestion, secondary incidents, and the associated human and economic losses, but also in effectively predicting incident duration time.

  1. Incidence of inguinal hernia in children with congenital cerebral palsy

    DEFF Research Database (Denmark)

    Reimers, J I; Latocha, J E

    1990-01-01

    The incidence of inguinal hernia among 247 children with cerebral palsy was ascertained. During the first year of life, 20 of the 153 boys developed hernia, as did one of the 94 girls. Among boys with birthweights of 1000 to 2000g the incidence was 31 per cent, which is twice the rate for normal...

  2. Basics of spectroscopic instruments. Hardware of NMR spectrometer

    International Nuclear Information System (INIS)

    Sato, Hajime

    2009-01-01

    NMR is a powerful tool for structure analysis of small molecules, natural products, biological macromolecules, synthesized polymers, samples from material science and so on. Magnetic Resonance Imaging (MRI) is applicable to plants and animals Because most of NMR experiments can be done by an automation mode, one can forget hardware of NMR spectrometers. It would be good to understand features and performance of NMR spectrometers. Here I present hardware of a modern NMR spectrometer which is fully equipped with digital technology. (author)

  3. Effect of jitter on an imaging FTIR spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C. L., LLNL

    1997-04-01

    Line of sight (LOS) jitter produces temporal modulations of the signals which are detected in the focal plane of a temporally modulated imaging Fourier Transform Spectrometer. A theoretical treatment of LOS jitter effects is given, and is compared with the results of measurements with LIFTIRS1 (the Livermore Imaging Fourier Transform InfraRed Spectrometer). The identification, isolation, quantification and removal of jitter artifacts in hyperspectral imaging data by means of principal components analysis is discussed. The theoretical distribution of eigenvalues expected from principal components analysis is used to determine the level of significance of spatially coherent instrumental artifacts in general, including jitter as a representative example. It is concluded that an imaging FTIR spectrometer is much less seriously impacted by a given LOS jitter level than a non imaging FTIR spectrometer.

  4. Resonant ultrasound spectrometer

    Science.gov (United States)

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

    1990-01-01

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

  5. Wide band ENDOR spectrometer

    International Nuclear Information System (INIS)

    Mendonca Filho, C.

    1973-01-01

    The construction of an ENDOR spectrometer operating from 0,5 to 75 MHz within a single band, with ore Klystron and homodine detection, and no fundamental changes on the electron spin resonance spectrometer was described. The ENDOR signal can be detected both by amplitude modulation of the frequency field, or direct detection of the ESR output, which is taken to a signal analyser. The signal-to-noise ratio is raised by averaging rather than filtering avoiding the use of long time constants, providing natural line widths. The experimental apparatus and the spectra obtained are described. A discussion, relating the ENDOR line amplitudes with the experimental conditions is done and ENDOR mechanism, in which there is a relevant presence of cross relaxation is proposed

  6. Pump induced normal mode splittings in phase conjugation in a Kerr ...

    Indian Academy of Sciences (India)

    Abstract. Phase conjugation in a Kerr nonlinear waveguide is studied with counter-propagating normally incident pumps and a probe beam at an arbitrary angle of incidence. Detailed numerical results for the specular and phase conjugated reflectivities are obtained with full account of pump depletion. For sufficient ...

  7. FIR and sub-mm direct detection spectrometers for spaceborne astronomy

    Science.gov (United States)

    Wijnbergen, Jan J.; de Graauw, Thijs

    1990-12-01

    Candidate spaceborne sub-mm instrumentation proposed for space projects with large passively cooled telescopes are reviewed. Grating instruments and Fourier transform spectroscopy (FTS) spectrometers are discussed. Particular attention is given to imaging Fabry-Perot spectrometers. The special needs of the Large Deployable Reflector (LDR) and for the Far InfraRed Space Telescope (FIRST) missions in this area are outlined. Possible Fabry-Perot spectrometer setups are diagrammed and outlined. The use of spherical and multiplex Fabry-Perot spectrometers is discussed.

  8. Liquid scintillation spectrometer survey 155Eu liquid activity

    International Nuclear Information System (INIS)

    Zhang Zuhua

    2002-01-01

    In the countrywide contrasting survey of 155 Eu activity, 155 Eu liquid activity was determined for the first time through using liquid scintillation spectrometer survey 155 Eu β ray. In survey total uncertainty, determining activity accord with determining activity average value of all a wide variety of survey instrument entering into contrasting survey. But using liquid scintillation spectrometer survey, it is simple and save time, is beyond compare for other survey method. It indicate liquid scintillation spectrometer survey β-γ nuclide activity is effective as well

  9. Forward spectrometers at the SSC

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1986-01-01

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

  10. Design and performance of a spin-polarized electron energy loss spectrometer with high momentum resolution

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, D.; Kirschner, J. [Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

    2016-08-15

    We describe a new “complete” spin-polarized electron energy loss spectrometer comprising a spin-polarized primary electron source, an imaging electron analyzer, and a spin analyzer of the “spin-polarizing mirror” type. Unlike previous instruments, we have a high momentum resolution of less than 0.04 Å{sup −1}, at an energy resolution of 90-130 meV. Unlike all previous studies which reported rather broad featureless data in both energy and angle dependence, we find richly structured spectra depending sensitively on small changes of the primary energy, the kinetic energy after scattering, and of the angle of incidence. The key factor is the momentum resolution.

  11. Multilayer x-ray mirrors for the objective crystal spectrometer on the Spectrum Roentgen Gamma satellite

    DEFF Research Database (Denmark)

    Louis, E.; Spiller, E.; Abdali, S.

    1995-01-01

    with Kr+- and Ar+- ions of 300, 500, and 1000 eV. We examined the effect of different polishing parameters on the smoothening of the Co- and Ni-layers. The in-situ reflectivity of lambda equals 3.16 nm during deposition and the ex-situ grazing incidence reflectivity of Cu-K(alpha ) radiation (lambda...... multiplied by 6 cm2 Si (111) crystals for the Objective Crystal Spectrometer on the Russian Spectrum Rontgen Gamma satellite. The coatings on the flight crystals have a period Lambda of 3.95 plus or minus 0.02 nm and a reflectivity of more than 8% averaged over s- and p-polarization over the entire...

  12. A new spectrometer for grazing incidence X-ray fluorescence for the characterization of Arsenic implants and Hf based high-k layers

    International Nuclear Information System (INIS)

    Ingerle, D.; Meirer, F.; Zoeger, N.; Pepponi, G.; Giubertoni, D.; Steinhauser, G.; Wobrauschek, P.; Streli, C.

    2010-01-01

    Grazing Incidence X-ray Fluorescence Analysis (GIXRF) is a powerful technique for depth-profiling and characterization of thin layers in depths up to a few hundred nanometers. By measurement of fluorescence signals at various incidence angles Grazing Incidence X-ray Fluorescence Analysis provides information on depth distribution and total dose of the elements in the layers. The technique is very sensitive even in depths of a few nanometers. As Grazing Incidence X-ray Fluorescence Analysis does not provide unambigous depth profile information and needs a realistic input depth profile for fitting, in the context of the EC funded European Integrated Activity of Excellence and Networking for Nano and Micro-Electronics Analysis (ANNA) Grazing Incidence X-ray Fluorescence Analysis is used as a complementary technique to Secondary Ion Mass Spectrometry (SIMS) for the characterization of Ultra Shallow Junctions (USJ). A measuring chamber was designed, constructed and tested to meet the requirements of Grazing Incidence X-ray Fluorescence Analysis. A measurement protocol was developed and tested. Some results for As implants as well as Hf based high k layers on Silicon are shown. For the determination of the bulk As content of the wafers, Instrumental Neutron Activation Analysis has also been applied for comparison.

  13. Triple axis spectrometers

    International Nuclear Information System (INIS)

    Clausen, K.N.

    1997-01-01

    Conventional triple-axis neutron spectroscopy was developed by Brockhouse over thirty years ago' and remains today a versatile and powerful tool for probing the dynamics of condensed matter. The original design of the triple axis spectrometer is technically simple and probes momentum and energy space on a point-by-point basis. This ability to systematically probe the scattering function in a way which only requires a few angles to be moved under computer control and where the observed data in general can be analysed using a pencil and graph paper or a simple fitting routine, has been essential for the success of the method. These constraints were quite reasonable at the time the technique was developed. Advances in computer based data acquisition, neutron beam optics, and position sensitive area detectors have been gradually implemented on many triple axis spectrometer spectrometers, but the full potential of this has not been fully exploited yet. Further improvement in terms of efficiency (beyond point by point inspection) and increased sensitivity (use of focusing optics whenever the problem allows it) could easily be up to a factor of 10-20 over present instruments for many problems at a cost which is negligible compared to that of increasing the flux of the source. The real cost will be in complexity - finding the optimal set-up for a given scan and interpreting the data as the they are taken. On-line transformation of the data for an appropriate display in Q, ω space and analysis tools will be equally important for this task, and the success of these new ideas will crucially depend on how well we solve these problems. (author)

  14. Adaptive Tunable Laser Spectrometer for Space Applications

    Science.gov (United States)

    Flesch, Gregory; Keymeulen, Didier

    2010-01-01

    An architecture and process for the rapid prototyping and subsequent development of an adaptive tunable laser absorption spectrometer (TLS) are described. Our digital hardware/firmware/software platform is both reconfigurable at design time as well as autonomously adaptive in real-time for both post-integration and post-launch situations. The design expands the range of viable target environments and enhances tunable laser spectrometer performance in extreme and even unpredictable environments. Through rapid prototyping with a commercial RTOS/FPGA platform, we have implemented a fully operational tunable laser spectrometer (using a highly sensitive second harmonic technique). With this prototype, we have demonstrated autonomous real-time adaptivity in the lab with simulated extreme environments.

  15. Calibration techniques for a fast duo-spectrometer

    International Nuclear Information System (INIS)

    Chapman, J.T.; Den Hartog, D.J.

    1996-06-01

    The authors have completed the upgrade and calibration of the Ion Dynamics Spectrometer (IDS), a high-speed Doppler duo-spectrometer which measures ion flow and temperature in the MST Reversed-field Pinch. This paper describes an in situ calibration of the diagnostic's phase and frequency response. A single clock was employed to generate both a digital test signal and a digitizer trigger thus avoiding frequency drift and providing a highly resolved measurement over the system bandwidth. Additionally, they review the measurement of the spectrometer instrument function and absolute intensity response. This calibration and subsequent performance demonstrate the IDS to be one of the fastest, highest throughput diagnostics of its kind. Typical measurements are presented

  16. A compact multichannel spectrometer for Thomson scatteringa)

    Science.gov (United States)

    Schoenbeck, N. L.; Schlossberg, D. J.; Dowd, A. S.; Fonck, R. J.; Winz, G. R.

    2012-10-01

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

  17. A compact multichannel spectrometer for Thomson scattering

    International Nuclear Information System (INIS)

    Schoenbeck, N. L.; Schlossberg, D. J.; Dowd, A. S.; Fonck, R. J.; Winz, G. R.

    2012-01-01

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

  18. A compact multichannel spectrometer for Thomson scattering.

    Science.gov (United States)

    Schoenbeck, N L; Schlossberg, D J; Dowd, A S; Fonck, R J; Winz, G R

    2012-10-01

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

  19. A GPU-Based Wide-Band Radio Spectrometer

    Science.gov (United States)

    Chennamangalam, Jayanth; Scott, Simon; Jones, Glenn; Chen, Hong; Ford, John; Kepley, Amanda; Lorimer, D. R.; Nie, Jun; Prestage, Richard; Roshi, D. Anish; Wagner, Mark; Werthimer, Dan

    2014-12-01

    The graphics processing unit has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable spectrometer built using an off-the-shelf graphics processing unit card. This spectrometer, when configured as a polyphase filter bank, supports a dual-polarisation bandwidth of up to 1.1 GHz (or a single-polarisation bandwidth of up to 2.2 GHz) on the latest generation of graphics processing units. On the other hand, when configured as a direct fast Fourier transform, the spectrometer supports a dual-polarisation bandwidth of up to 1.4 GHz (or a single-polarisation bandwidth of up to 2.8 GHz).

  20. SWIFTS: on-chip very high spectral resolution spectrometer

    Science.gov (United States)

    le Coarer, E.; Venancio, L. G.; Kern, P.; Ferrand, J.; Puget, P.; Ayraud, M.; Bonneville, C.; Demonte, B.; Morand, A.; Boussey, J.; Barbier, D.; Blaize, S.; Gonthiez, T.

    2017-11-01

    The size and the weight of state of the art spectrometers is a serious issue regarding space applications. SWIFTS (Stationary Wave Integrated Fourier Transform Spectrometer) is a new FTS family without any moving part. This very promising technology is an original way to fully sample the Fourier interferogram obtained in a waveguide by either a reflection (SWIFTS Lippmann) or counter-propagative (SWIFTS Gabor) interference phenomenon. The sampling is simultaneously performed the optical path thanks to "nano-detectors" located in the evanescent field of the waveguide. For instance a 1.7cm long waveguide properly associated to the detector achieves directly a resolution of 0.13cm-1 on a few centimetre long instruments. Here, firstly we present the development status of this new kind of spectrometers and the first results obtained with on going development of spectrometer covering simultaneously the visible domain from 400 to 1000 nm like an Echelle spectrometer. Valuable technologies allows one to extend the concept to various wavelength domains. Secondly, we present the results obtained in the frame of an activity funded by the European Space Agency where several potential applications in space missions have been identified and studied.

  1. FERDO/FERD, Unfolding of Pulse-Height Spectrometer Spectra

    International Nuclear Information System (INIS)

    Rust, B.W.; Ingersoll, D.T.; Burrus, W.R.

    1985-01-01

    1 - Description of problem or function: FERDO and FERD are unfolding codes which can be used to correct observed pulse-height distributions for the non-ideal response of a pulse-height spectrometer or to solve poorly conditioned linear equations. 2 - Method of solution: It is assumed that the response of the spectrometer is given by Ax = b, where A is the spectrometer response function matrix, x is the unknown spectrum, and b is the pulse-height distribution. FERDO does not resolve directly for x but instead solves for p = Wx, where W is a 'window function matrix'. Typically, W is the resolution function of an ideal spectrometer which has a single Gaussian response. The effective resolution of the unfolding solution may be varied by the choice of W. Confidence intervals are found for each element of the solution p

  2. Two-arm semiconductor spectrometer for charged particles for the investigation of absorption by nuclei of stopped negative pions

    International Nuclear Information System (INIS)

    Gornov, M.G.; Gurov, Yu.B.; Lukin, A.S.; Morokhov, P.V.; Pechkurov, V.A.; Pichugin, A.P.; Saveliev, V.I.; Shafigullin, R.R.; Sergeev, F.M.; Khomutov, A.A.; Oganesian, K.O.; Osipenko, B.P.; Sandukovsky, V.G.

    1984-01-01

    A two-arm semiconductor spectrometer for the detection of secondary charged particles, such as p, d, t, 3 He, 4 He and of their correlations in the process of stopped pion absorption by nuclei is described. The spectrometer consists of two telescopes of Si-detectors with a sensitive surface of 800 mm 2 , two semiconductor detectors as monitors and the 'live' target, a silicon surface barrier detector. The number of semiconductor detectors is 19. A technique for pion stop selection in thin targets is described. The problem of particle identification and of measurements of their energy with the help of a multicrystal semiconductor telescope is discussed. The technique provides an absolute normalization of spectra. The 'alive' target helps to obtain more information on the process of pion absorption by Si-nuclei. (orig.)

  3. A NMR spectrometer for educational purposes; Espectrometro de RMN para ensino

    Energy Technology Data Exchange (ETDEWEB)

    Colnago, Luiz A; Torre Neto, Andre [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Sao Carlos, SP (Brazil). Nucleo de Pesquisa e Desenvolvimento de Instrumentacao Agropecuaria; Villar, Jose D.F.; Seidl, Peter R [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)

    1992-12-31

    A NMR spectrometer has been constructed for educational purposes, such as teaching of the technique basic principles and instrumentation. The spectrometer has been designed with a minimum number of components so that the students may have acquittance with both the spectrometer, through block diagrams, and the small numbers of existent components . The device was based on a 0.t Tesla magnet from the continuous wave spectrometer (E M 300 - Varian) existent at the Instituto Militar de Engenharia, and it is expected to facilitate the comprehension of the commercial spectrometers 1 ref., 3 figs.

  4. Effects of Different LiDAR Intensity Normalization Methods on Scotch Pine Forest Leaf Area Index Estimation

    Directory of Open Access Journals (Sweden)

    YOU Haotian

    2018-02-01

    Full Text Available The intensity data of airborne light detection and ranging (LiDAR are affected by many factors during the acquisition process. It is of great significance for the normalization and application of LiDAR intensity data to study the effective quantification and normalization of the effect from each factor. In this paper, the LiDAR data were normalized with range, angel of incidence, range and angle of incidence based on radar equation, respectively. Then two metrics, including canopy intensity sum and ratio of intensity, were extracted and used to estimate forest LAI, which was aimed at quantifying the effects of intensity normalization on forest LAI estimation. It was found that the range intensity normalization could improve the accuracy of forest LAI estimation. While the angle of incidence intensity normalization did not improve the accuracy and made the results worse. Although the range and incidence angle normalized intensity data could improve the accuracy, the improvement was less than the result of range intensity normalization. Meanwhile, the differences between the results of forest LAI estimation from raw intensity data and normalized intensity data were relatively big for canopy intensity sum metrics. However, the differences were relatively small for the ratio of intensity metrics. The results demonstrated that the effects of intensity normalization on forest LAI estimation were depended on the choice of affecting factor, and the influential level is closely related to the characteristics of metrics used. Therefore, the appropriate method of intensity normalization should be chosen according to the characteristics of metrics used in the future research, which could avoid the waste of cost and the reduction of estimation accuracy caused by the introduction of inappropriate affecting factors into intensity normalization.

  5. MEOS Microsatellite Earth Observation using Miniature Integrated-Optic IR Spectrometers

    Science.gov (United States)

    Kruzelecky, Roman

    Our planetary atmosphere helps to regulate the Earth's thermal budget and the resulting global climate by controlling the energy balance between the incident solar radiation and the thermal emission to space from the Earth's atmosphere and surface. Certain atmospheric gases, most importantly H2 O vapour and CO2 , can absorb some of the Earth's emitted IR radiation and trap it in the atmosphere to provide an atmospheric greenhouse effect that currently adds about 38 K to the Earth's mean surface temperature. The associated greenhouse gas (GHG) and water cycles are a complex balance of interactions among surface ecosystems and atmospheric processes. The natural water and carbon cycles are being measurably disrupted by anthropogenic activities. Since the industrial revolution, significant anthropogenic sources of greenhouse gases and aerosols have evolved, while natural sinks, such as forests and wetlands, are being destroyed. Changes in the land cover affect the balance of GHG sources and sinks, as well as the Albedo and resultant surface temperature. Water vapour, the most abundant GHG, is affected indirectly though the influence of aerosols on cloud formation and precipitation patterns, and directly through the influence of surface temperatures on the water evaporation rates. There is also positive feedback between the water and carbon cycles. For example, drought can result in desertification with subsequent release of stored carbon. It is clear that the common thread in all of these climate-related effects is the interaction between the surface ecosystems and the carbonand nitrogen-containing gases in the lower troposphere. Uptake of CO2 by growing vegetation, release of CH4 and N2 O by soil processes, and the effects of carbon and water cycle chemistry all interact strongly in a system that is both ex-tremely complex and poorly understood at the present time. In order to quantify these processes and provide a clearer prediction of their likely effects in the

  6. MAGNETIC SPECTROMETER DESIGN FOR ELECTRON SCATTERING ABOVE 1 Bev

    Energy Technology Data Exchange (ETDEWEB)

    Schopper, H.

    1963-06-15

    Design considerations are discussed for magnetic spectrometer electron scattering investigations with the higher energy (above 1 Bev) electron sources which are being developed. The spectrometers are to be used to discriminate between elastic and inelastic processes. A momentum resolution of the order of one per cent is required for these experiments. Various spectrometers are compared according to their optical properties and the number of magnets they consist of. (R.E.U.)

  7. Structure and Dissipation Characteristics of an Electron Diffusion Region Observed by MMS During a Rapid, Normal-Incidence Magnetopause Crossing

    Science.gov (United States)

    Torbert, R. B.; Burch, J. L.; Argall, M. R.; Alm, L.; Farrugia, C. J.; Forbes, T. G.; Giles, B. L.; Rager, A.; Dorelli, J.; Strangeway, R. J.; Ergun, R. E.; Wilder, F. D.; Ahmadi, N.; Lindqvist, P.-A.; Khotyaintsev, Y.

    2017-12-01

    On 22 October 2016, the Magnetospheric Multiscale (MMS) spacecraft encountered the electron diffusion region (EDR) when the magnetosheath field was southward, and there were signatures of fast reconnection, including flow jets, Hall fields, and large power dissipation. One rapid, normal-incidence crossing, during which the EDR structure was almost stationary in the boundary frame, provided an opportunity to observe the spatial structure for the zero guide field case of magnetic reconnection. The reconnection electric field was determined unambiguously to be 2-3 mV/m. There were clear signals of fluctuating parallel electric fields, up to 6 mV/m on the magnetosphere side of the diffusion region, associated with a Hall-like parallel current feature on the electron scale. The width of the main EDR structure was determined to be 2 km (1.8 de). Although the MMS spacecraft were in their closest tetrahedral separation of 8 km, the divergences and curls for these thin current structures could therefore not be computed in the usual manner. A method is developed to determine these quantities on a much smaller scale and applied to compute the normal component of terms in the generalized Ohm's law for the positions of each individual spacecraft (not a barocentric average). Although the gradient pressure term has a qualitative dependence that follows the observed variation of E + Ve × B, the quantitative magnitude of these terms differs by more than a factor of 2, which is shown to be greater than the respective errors. Thus, future research is required to find the manner in which Ohm's law is balanced.

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

    Science.gov (United States)

    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.

  9. Miniature Neutron-Alpha Activation Spectrometer

    Science.gov (United States)

    Rhodes, E.; Goldsten, J.

    2001-01-01

    We are developing a miniature neutron-alpha activation spectrometer for in situ analysis of samples including rocks, fines, ices, and drill cores, suitable for a lander or Rover platform, that would meet the severe mass, power, and environmental constraints of missions to the outer planets. In the neutron-activation mode, a gamma-ray spectrometer will first perform a penetrating scan of soil, ice, and loose material underfoot (depths to 10 cm or more) to identify appropriate samples. Chosen samples will be analyzed in bulk in neutron-activation mode, and then the sample surfaces will be analyzed in alpha-activation mode using Rutherford backscatter and x-ray spectrometers. The instrument will provide sample composition over a wide range of elements, including rock-forming elements (such as Na, Mg, Si, Fe, and Ca), rare earths (Sm and Eu for example), radioactive elements (K, Th, and U), and light elements present in water, ices, and biological materials (mainly H, C, O, and N). The instrument is expected to have a mass of about l kg and to require less than 1 W power. Additional information is contained in the original extended abstract.

  10. VERITAS: Versatile Triple-Axis Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il

    2006-04-15

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, {approx} 5 m Curved Guide, {approx} 26 m w/ R 1500 m Straight Guide before the Instrument, {approx} 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world.

  11. VERITAS: Versatile Triple-Axis Spectrometer

    International Nuclear Information System (INIS)

    Park, Sung Il

    2006-04-01

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, ∼ 5 m Curved Guide, ∼ 26 m w/ R 1500 m Straight Guide before the Instrument, ∼ 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world

  12. Theory and optical design of x-ray echo spectrometers

    Science.gov (United States)

    Shvyd'ko, Yuri

    2017-08-01

    X-ray echo spectroscopy, a space-domain counterpart of neutron spin echo, is a recently proposed inelastic x-ray scattering (IXS) technique. X-ray echo spectroscopy relies on imaging IXS spectra and does not require x-ray monochromatization. Due to this, the echo-type IXS spectrometers are broadband, and thus have a potential to simultaneously provide dramatically increased signal strength, reduced measurement times, and higher resolution compared to the traditional narrow-band scanning-type IXS spectrometers. The theory of x-ray echo spectrometers presented earlier [Yu. Shvyd'ko, Phys. Rev. Lett. 116, 080801 (2016), 10.1103/PhysRevLett.116.080801] is developed here further with a focus on questions of practical importance, which could facilitate optical design and assessment of the feasibility and performance of the echo spectrometers. Among others, the following questions are addressed: spectral resolution, refocusing condition, echo spectrometer tolerances, refocusing condition adjustment, effective beam size on the sample, spectral window of imaging and scanning range, impact of the secondary source size on the spectral resolution, angular dispersive optics, focusing and collimating optics, and detector's spatial resolution. Examples of optical designs and characteristics of echo spectrometers with 1-meV and 0.1-meV resolutions are presented.

  13. Standalone vertex finding in the ATLAS muon spectrometer

    DEFF Research Database (Denmark)

    Aad, A.; Abajyan, T.; Abbott, B.

    2014-01-01

    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The perf......A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths....... The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011....

  14. Electron-ion-x-ray spectrometer system

    International Nuclear Information System (INIS)

    Southworth, S.H.; Deslattes, R.D.; MacDonald, M.A.

    1993-01-01

    The authors describe a spectrometer system developed for electron, ion, and x-ray spectroscopy of gas-phase atoms and molecules following inner-shell excitation by tunable synchrotron radiation. The spectrometer has been used on beamline X-24A at the National Synchrotron Light Source for excitation-dependent studies of Ar L-shell and K-shell photoexcitation and vacancy decay processes. The instrumentation and experimental methods are discussed, and examples are given of electron spectra and coincidence spectra between electrons and fluorescent x-rays

  15. Electronic THz-spectrometer for plasmonic enhanced deep subwavelength layer detection

    NARCIS (Netherlands)

    Berrier, A.; Schaafsma, M.C.; Gómez Rivas, J.; Schäfer-Eberwein, H.; Haring Bolivar, P.; Tripodi, L.; Matters-Kammerer, M.K.

    2015-01-01

    We demonstrate the operation of a miniaturized all-electronic CMOS based THz spectrometer with performances comparable to that of a THz-TDS spectrometer in the frequency range 20 to 220 GHz. The use of this all-electronic THz spectrometer for detection of a thin TiO2 layer and a B. subtilis bacteria

  16. Design of a miniaturized integrated spectrometer for spectral tissue sensing

    Science.gov (United States)

    Belay, Gebirie Yizengaw; Hoving, Willem; Ottevaere, Heidi; van der Put, Arthur; Weltjens, Wim; Thienpont, Hugo

    2016-04-01

    Minimally-invasive image-guided procedures become increasingly used by physicians to obtain real-time characterization feedback from the tissue at the tip of their interventional device (needle, catheter, endoscopic or laparoscopic probes, etc…) which can significantly improve the outcome of diagnosis and treatment, and ultimately reduce cost of the medical treatment. Spectral tissue sensing using compact photonic probes has the potential to be a valuable tool for screening and diagnostic purposes, e.g. for discriminating between healthy and tumorous tissue. However, this technique requires a low-cost broadband miniature spectrometer so that it is commercially viable for screening at point-of-care locations such as physicians' offices and outpatient centers. Our goal is therefore to develop a miniaturized spectrometer based on diffractive optics that combines the functionalities of a visible/near-infrared (VIS/NIR) and shortwave-infrared (SWIR) spectrometer in one very compact housing. A second goal is that the hardware can be produced in high volume at low cost without expensive time consuming alignment and calibration steps. We have designed a miniaturized spectrometer which operates both in the visible/near-infrared and shortwave-infrared wavelength regions ranging from 400 nm to 1700 nm. The visible/near-infrared part of the spectrometer is designed for wavelengths from 400 nm to 800 nm whereas the shortwave-infrared segment ranges from 850 nm to 1700 nm. The spectrometer has a resolution of 6 nm in the visible/near-infrared wavelength region and 10 nm in the shortwave-infrared. The minimum SNR of the spectrometer for the intended application is about 151 in the VIS/NIR range and 6000 for SWIR. In this paper, the modelling and design, and power budget analysis of the miniaturized spectrometer are presented. Our work opens a door for future affordable micro- spectrometers which can be integrated with smartphones and tablets, and used for point

  17. Feasibility study of a SiC sandwich neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jian, E-mail: caepwujian@163.com [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Lei, Jiarong, E-mail: jiarong_lei@163.com [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Jiang, Yong; Chen, Yu; Rong, Ru; Zou, Dehui; Fan, Xiaoqiang [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan Province (China); Chen, Gang; Li, Li; Bai, Song [Nanjing Electronic Devices Institute, Nanjing 210016 (China)

    2013-04-21

    Semiconductor sandwich neutron spectrometers are suitable for in-pile measurements of fast reactor spectra thanks to their compact and relatively simple design. We have assembled and tested a sandwich neutron spectrometer based on 4H-silicon carbide (4H-SiC) Schottky diodes. The SiC diodes detect neutrons via neutron-induced charged particles (tritons and alpha particles) produced by {sup 6}Li(n,α){sup 3}H reaction. {sup 6}LiF neutron converter layers are deposited on the front surface of Schottky diodes by magnetron sputtering. The responses of SiC diodes to charged particles were investigated with an {sup 241}Am alpha source. A sandwich neutron spectrometer was assembled with two SiC Schottky diodes selected based on the charged-particle-response experimental results. The low-energy neutron response of the sandwich spectrometer was measured in the neutron field of the Chinese Fast Burst Reactor-II (CFBR-II). Spectra of alpha particles and tritons from {sup 6}Li(n,α){sup 3}H reaction were obtained with two well-resolved peaks. The energy resolution of the sum spectrum was 8.8%. The primary experimental results confirmed the 4H-SiC sandwich neutron spectrometer's feasibility. -- Highlights: ► Sandwich neutron spectrometer employing 4H-SiC as a detecting material has been developed for the first time. ► {sup 6}LiF neutron converter has been deposited on the surface of 4H-SiC Schottky diode. ► Preliminary testing results obtained with the 4H-SiC sandwich neutron spectrometer are presented.

  18. Evaluation of HOPG mounting possibilities for multiplexing spectrometers

    DEFF Research Database (Denmark)

    Groitl, Felix; Bartkowiak, Marek; Bergmann, Ryan M.

    2017-01-01

    Four different methods for mounting HOPG analyzer crystals on Si holders have been evaluated in the design process of the new multiplexing spectrometer CAMEA. Contrary to neutron optics used in standard spectrometers, the new instrument concept employs a series of analyzer segments behind each...

  19. Evaluation of HOPG mounting possibilities for multiplexing spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Groitl, Felix, E-mail: felix.groitl@psi.ch [Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland); Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Bartkowiak, Marek [Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut, 5232 Villigen (Switzerland); Bergmann, Ryan M. [Division Large Research Facilities, Paul Scherrer Institut, 5232 Villigen (Switzerland); Birk, Jonas Okkels [Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Department of Physics, Technical University of Denmark (DTU), 2800 Kgs. Lyngby (Denmark); Markó, Márton [Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Wigner Research Centre for Physics, Neutron Spectroscopy Department, 1525 Budapest (Hungary); Bollhalder, Alex; Graf, Dieter [Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut, 5232 Villigen (Switzerland); Niedermayer, Christof [Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Rüegg, Christian [Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Department of Quantum Matter Physics, University of Geneva, 1211 Geneva (Switzerland); Rønnow, Henrik M. [Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland); Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark)

    2017-06-21

    Four different methods for mounting HOPG analyzer crystals on Si holders have been evaluated in the design process of the new multiplexing spectrometer CAMEA. Contrary to neutron optics used in standard spectrometers, the new instrument concept employs a series of analyzer segments behind each other where the neutrons have to pass through the bonding compound of the different analyzer crystals. The different methods, namely screws, shellac, indium soldering and clips, have been evaluated with regards to background, transmission, cooling, activation and handling. The results presented here will give valuable input for future CAMEA-type spectrometers currently planned and designed at various neutron sources.

  20. Design and Test of Portable Hyperspectral Imaging Spectrometer

    Directory of Open Access Journals (Sweden)

    Chunbo Zou

    2017-01-01

    Full Text Available We design and implement a portable hyperspectral imaging spectrometer, which has high spectral resolution, high spatial resolution, small volume, and low weight. The flight test has been conducted, and the hyperspectral images are acquired successfully. To achieve high performance, small volume, and regular appearance, an improved Dyson structure is designed and used in the hyperspectral imaging spectrometer. The hyperspectral imaging spectrometer is suitable for the small platform such as CubeSat and UAV (unmanned aerial vehicle, and it is also convenient to use for hyperspectral imaging acquiring in the laboratory and the field.

  1. Evaluation of HOPG mounting possibilities for multiplexing spectrometers

    International Nuclear Information System (INIS)

    Groitl, Felix; Bartkowiak, Marek; Bergmann, Ryan M.; Birk, Jonas Okkels; Markó, Márton; Bollhalder, Alex; Graf, Dieter; Niedermayer, Christof; Rüegg, Christian; Rønnow, Henrik M.

    2017-01-01

    Four different methods for mounting HOPG analyzer crystals on Si holders have been evaluated in the design process of the new multiplexing spectrometer CAMEA. Contrary to neutron optics used in standard spectrometers, the new instrument concept employs a series of analyzer segments behind each other where the neutrons have to pass through the bonding compound of the different analyzer crystals. The different methods, namely screws, shellac, indium soldering and clips, have been evaluated with regards to background, transmission, cooling, activation and handling. The results presented here will give valuable input for future CAMEA-type spectrometers currently planned and designed at various neutron sources.

  2. A data reduction program for the linac total-scattering amorphous materials spectrometer (LINDA)

    International Nuclear Information System (INIS)

    Clarke, J.H.

    1976-01-01

    A computer program has been written to reduce the data collected on the A.E.R.E., Harwell linac total-scattering spectrometer (TSS) to the differential scattering cross-section. This instrument, used for studying the structure of amorphous materials such as liquids and glasses, has been described in detail. Time-of-flight spectra are recorded by several arrays of detectors at different angles using a pulsed incident neutron beam with a continuous distribution of wavelengths. The program performs all necessary background and container subtractions and also absorption corrections using the method of Paalman and Pings. The incident neutron energy distribution is obtained from the intensity recorded from a standard vanadium sample, enabling the observed differential scattering cross-section dsigma/dΩ (theta, lambda) and the structure factor S(Q) to be obtained. Various sample and vanadium geometries can be analysed by the program and facilities exist for the summation of data sets, smoothing of data, application of Placzek corrections and the output of processed data onto magnetic tape or punched cards. A set of example data is provided and some structure factors are shown with absorption corrections. (author)

  3. Incidence of cervical dysplasia and cervical cancer in women living with HIV in Denmark

    DEFF Research Database (Denmark)

    Thorsteinsson, Kristina; Ladelund, Steen; Jensen-Fangel, Søren

    2014-01-01

    and hazard ratios (HRs) for time from inclusion to first cervical intraepithelial neoplasia (CIN)/ICC and time from first normal cervical cytology to first CIN/ICC were estimated. Sensitivity analyses were performed to include prior screening outcome, screening intensity and treatment of CIN......INTRODUCTION: Women living with HIV (WLWH) are reportedly at increased risk of invasive cervical cancer (ICC). WLWH in Denmark attend the National ICC screening program less often than women in the general population. We aimed to estimate the incidence of cervical dysplasia and ICC in WLWH...... with normal baseline cytology, incidences of CIN1+ and CIN2+ were higher in WLWH. However, incidences were comparable between WLWH and controls adherent to the National ICC screening program. CONCLUSIONS: Overall, WLWH develop more cervical disease than controls. However, incidences of CIN are comparable...

  4. Mass-spectrometer of knock-on nuclei for reactor 'Pik'

    International Nuclear Information System (INIS)

    Begzhanov, P.B.; Nazarov, A.G.; Petrov, G.A.; Pikul', V.P.

    1999-01-01

    For reactor 'Pik' (that is being built in St. Petersburg Institute of Nuclear Physics) there was designed a universal two shoulder mass-spectrometer for non-decelerated fission products (FP) of nuclei. The spectrometer helps to obtain different values of linear magnification, dispersion, aberration coefficients and transmission without making structural changes in the device. To separate FP for one shoulder of spectrometer we chose ion-optical scheme (IOS) consisting of three electrostatic analyzers and three-sectional magnet 'JOSEF' that had high dispersion by masses at small deflection radius. IOS calculations of mass-spectrometer were performed with the help of program TRANSVOL (transfer of phase volume) designed basing on TRIO program. The program allows calculating of complete IOS transmission with taking into account elements aperture and beam officering

  5. High Resolution Stellar Spectroscopy with VBT Echelle Spectrometer

    Indian Academy of Sciences (India)

    Easy operations. We finally preferred the all transmitting system for the spectrometer with the optical surfaces anti-reflection coated to optimize the throughput rather than reflecting cameras with central obscurations. Following other optimized throughput spectrometers like. Sandiford at McDonald Observatory (McCarthy et al ...

  6. Scanning electron microscopy-energy dispersive X-ray spectrometer ...

    African Journals Online (AJOL)

    The distribution of arsenic (As) and cadmium (Cd) in himematsutake was analyzed using scanning electron microscopy-energy dispersive X-ray spectrometer (SEM-EDX). The atomic percentage of the metals was confirmed by inductively coupled plasma-mass spectrometer (ICP-MS). Results show that the accumulation of ...

  7. Integrated Lloyd's mirror on planar waveguide facet as a spectrometer.

    Science.gov (United States)

    Morand, Alain; Benech, Pierre; Gri, Martine

    2017-12-10

    A low-cost and simple Fourier transform spectrometer based on the Lloyd's mirror configuration is proposed in order to have a very stable interferogram. A planar waveguide coupled to a fiber injection is used to spatially disperse the optical beam. A second beam superposed to the previous one is obtained by a total reflection of the incident beam on a vertical glass face integrated in the chip by dicing with a specific circular precision saw. The interferogram at the waveguide output is imaged on a near-infrared camera with an objective lens. The contrast and the fringe period are thus dependent on the type and the fiber position and can be optimized to the pixel size and the length of the camera. Spectral resolution close to λ/Δλ=80 is reached with a camera with 320 pixels of 25 μm width in a wavelength range from O to L bands.

  8. Indigenously built resonance ionization mass spectrometer

    International Nuclear Information System (INIS)

    Razvi, M.A.N.; Jayasekharan, T.; Thankarajan, K.; Guhagarkar, M.B.; Dixit, M.N.; Bhale, G.L.

    2000-04-01

    Design, fabrication and performance testing of an indigenously built Resonance Ionization Mass Spectrometer (RIMS) is presented in this report. The instrument is totally indigenous, but for the laser components consisting of the excimer laser and tunable dye lasers. Constructional details of atomic beam source and linear time-of-flight mass spectrometer are included. Finally, commissioning and performance testing of the instrument is described. Mass resolving power of 400 and a detection limit of 100 atoms has been achieved using this RIMS set-up. (author)

  9. Design of ITER divertor VUV spectrometer and prototype test at KSTAR tokamak

    Science.gov (United States)

    Seon, Changrae; Hong, Joohwan; Song, Inwoo; Jang, Juhyeok; Lee, Hyeonyong; An, Younghwa; Kim, Bosung; Jeon, Taemin; Park, Jaesun; Choe, Wonho; Lee, Hyeongon; Pak, Sunil; Cheon, MunSeong; Choi, Jihyeon; Kim, Hyeonseok; Biel, Wolfgang; Bernascolle, Philippe; Barnsley, Robin; O'Mullane, Martin

    2017-12-01

    Design and development of the ITER divertor VUV spectrometer have been performed from the year 1998, and it is planned to be installed in the year 2027. Currently, the design of the ITER divertor VUV spectrometer is in the phase of detail design. It is optimized for monitoring of chord-integrated VUV signals from divertor plasmas, chosen to contain representative lines emission from the tungsten as the divertor material, and other impurities. Impurity emission from overall divertor plasmas is collimated through the relay optics onto the entrance slit of a VUV spectrometer with working wavelength range of 14.6-32 nm. To validate the design of the ITER divertor VUV spectrometer, two sets of VUV spectrometers have been developed and tested at KSTAR tokamak. One set of spectrometer without the field mirror employs a survey spectrometer with the wavelength ranging from 14.6 nm to 32 nm, and it provides the same optical specification as the spectrometer part of the ITER divertor VUV spectrometer system. The other spectrometer with the wavelength range of 5-25 nm consists of a commercial spectrometer with a concave grating, and the relay mirrors with the same geometry as the relay mirrors of the ITER divertor VUV spectrometer. From test of these prototypes, alignment method using backward laser illumination could be verified. To validate the feasibility of tungsten emission measurement, furthermore, the tungsten powder was injected in KSTAR plasmas, and the preliminary result could be obtained successfully with regard to the evaluation of photon throughput. Contribution to the Topical Issue "Atomic and Molecular Data and their Applications", edited by Gordon W.F. Drake, Jung-Sik Yoon, Daiji Kato, Grzegorz Karwasz.

  10. Design and construction of a NIR spectrometer

    CERN Document Server

    Barcala-Riveira, J M; Fernandez-Marron, J L; Molero-Menendez, F; Navarrete-Marin, J J; Oller-Gonzalez, J C

    2003-01-01

    This document describes the design and construction of a NIR spectrometer based on an acoustic-optic tunable filter. The spectrometer will be used for automatic identification of plastics in domestic waste. The system works between 1200 and 1800 nm. Instrument is controlled by a personal computer. Computer receives and analyses data. A software package has been developed to do these tasks. (Author) 27 refs.

  11. 1987 calibration of the TFTR neutron spectrometers

    International Nuclear Information System (INIS)

    Barnes, C.W.; Strachan, J.D.; Princeton Univ., NJ

    1989-12-01

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

  12. Design and construction of a NIR spectrometer

    International Nuclear Information System (INIS)

    Barcala Riveira, J. M.; Fernandez Marron, J. L.; Alberdi Primicia, J.; Molero Menendez, F.; Navarrete Marin, J. J.; Oller Gonzalez, J. C.

    2003-01-01

    This document describes the design and construction of a NIR spectrometer based on an acoustic-optic tunable filter. The spectrometer will be used for automatic identification of plastics in domestic waste. The system works between 1200 and 1800 nm. Instrument is controlled by a personal computer. Computer receives and analyses data. A software package has been developed to do these tasks. (Author) 27 refs

  13. 77 FR 32006 - Special Conditions: Gulfstream Model GVI Airplane; High Incidence Protection

    Science.gov (United States)

    2012-05-31

    ... Special Conditions No. 25-423-SC] Special Conditions: Gulfstream Model GVI Airplane; High Incidence... pertaining to a high incidence protection system that replaces the stall warning system during normal... the condition existing in the test or performance standard in which V SR is being used. (3) The weight...

  14. IPNS-I chopper spectrometers

    International Nuclear Information System (INIS)

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

    1982-01-01

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

  15. Deep-water gamma-spectrometer based on HP(Ge) detector

    International Nuclear Information System (INIS)

    Sokolov, A.; Danengirsh, S.; Popov, S.; Pchelincev, A; Gostilo, V.; Kravchenko, S.; Shapovalov, V.; Druzhinin, A.

    1995-01-01

    Full text: For radionuclide monitoring of the sea bottom near underwater storage of high active waste of nuclear industries and near places of accidents with nuclear submarines the spectrometers of gamma-radiation, which allow to carry out the measurements on the great depth, are needed. Usually, these problems are solved with devices, which are cast down into the water, using the rope, and transmit the signals on the surface by the cable. However, the depth of immersion is limited by this construction and often the conditions of measurement are complicated. The deep water gamma-spectrometer based on HP(Ge) detector for the measurement on the depth up to 3000 m is developed. The spectrometer is completely autonomic and is put up in the selected place, using the manipulator of a deep-water apparatus. The spectrometer is created in two cylindrical cases with 170 mm diameter and 1100 mm length, bearing the high hydrostatic pressure. The part of the case around the detector is created from titanium and has especial construction with a thin wall for increasing the efficiency of registration in the region of low-energy gamma-radiation. The cooling of the semiconductor detector is provided by a coolant which supports the working temperature of the detector during more than 24 hours. The electronic system of the spectrometer includes high voltage supply f or the detector, preamplifier, analog processor, analog-digital converter and a device for collecting and storing information in flash memory. The power supply of the spectrometer is provided by a battery of accumulators, which can be recharged on the surface. The programming of the processor is carried out before immersion by connecting the spectrometer to personal computer using standard interface RS-232. During 24 hours the spectrometer provides registration of 16 spectrums each in 4096 channels. The reading of the information by the computer is carried out after lifting up the spectrometer on the surface in the same

  16. Investigation of background processes in the KATRIN main spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Axel [Karlsruhe Institute of Technology (KIT), Institut fuer Kernphysik (IKP) (Germany); Collaboration: KATRIN-Collaboration

    2016-07-01

    The KArlsruhe TRItium Neutrino experiment aims to probe the mass of the electron antineutrino in a model-independent way with an unsurpassed sensitivity of m{sub ν}=200 meV/c{sup 2} (90% C.L.). In order to determine the neutrino mass, the energy spectrum of electrons from the tritium β-decay is analyzed by a high-resolution electrostatic spectrometer which is based on the MAC-E filter principle. To keep the influence of the spectrometer background on the neutrino mass sensitivity small, KATRIN aims for a background level of 0.01 cps. For the investigation of different background components such as cosmic muons, external gamma radiation and the radioactive decay of isotopes in the volume of the spectrometer or on its surface, a series of dedicated measurements were performed with a combined system of main spectrometer and detector. This talk presents the results of measurements focusing on the secondary electron production at the inner surface of the spectrometer and compare them with electro-magnetic electron tracking simulations performed with the KATRIN developed simulation software KASSIOPEIA.

  17. BIS-2 spectrometer for search and investigation of narrow resonances

    International Nuclear Information System (INIS)

    Aleev, A.N.; Aref'ev, V.A.; Balandin, V.P.

    1989-01-01

    The configuration and main characteristics of the BIS-2 spectrometer are described. The spectrometer was intended to search for and to investigate charmed particles and narrow resonances produced in neutron-nucleus interactions. It was placed on a neutron beam of the Serpukhov accelerator. The Monte-Carlo simulated and experimentally measured characteristics of individual elements and the spectrometer as a whole are described. A brief review of the principal results based on the analysis of more than 10 7 neutron-nucleus interactions registered by means of the BIS-2 spectrometer is given. 34 refs.; 8 figs.; 5 tabs

  18. Beam-transport optimization for cold-neutron spectrometer

    Directory of Open Access Journals (Sweden)

    Nakajima Kenji

    2015-01-01

    Full Text Available We report the design of the beam-transport system (especially the vertical geometry for a cold-neutron disk-chopper spectrometer AMATERAS at J-PARC. Based on the elliptical shape, which is one of the most effective geometries for a ballistic mirror, the design was optimized to obtain, at the sample position, a neutron beam with high flux without serious degrading in divergence and spacial homogeneity within the boundary conditions required from actual spectrometer construction. The optimum focal point was examined. An ideal elliptical shape was modified to reduce its height without serious loss of transmission. The final result was adapted to the construction requirements of AMATERAS. Although the ideas studied in this paper are considered for the AMATERAS case, they can be useful also to other spectrometers in similar situations.

  19. A compact multichannel spectrometer for Thomson scattering

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-10-15

    The availability of high-efficiency volume phase holographic (VPH) gratings and intensified CCD (ICCD) cameras have motivated a simplified, compact spectrometer for Thomson scattering detection. Measurements of T{sub e} < 100 eV are achieved by a 2971 l/mm VPH grating and measurements T{sub e} > 100 eV by a 2072 l/mm VPH grating. The spectrometer uses a fast-gated ({approx}2 ns) ICCD camera for detection. A Gen III image intensifier provides {approx}45% quantum efficiency in the visible region. The total read noise of the image is reduced by on-chip binning of the CCD to match the 8 spatial channels and the 10 spectral bins on the camera. Three spectrometers provide a minimum of 12 spatial channels and 12 channels for background subtraction.

  20. Plasmonic Light Scattering in Textured Silicon Solar Cells with Indium Nanoparticles from Normal to Non-Normal Light Incidence

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Ho

    2017-07-01

    Full Text Available In this study, we sought to improve the light trapping of textured silicon solar cells using the plasmonic light scattering of indium nanoparticles (In NPs of various dimensions. The light trapping modes of textured-silicon surfaces with and without In NPs were investigated at an angle of incidence (AOI ranging from 0° to 75°. The optical reflectance, external quantum efficiency (EQE, and photovoltaic performance were first characterized under an AOI of 0°. We then compared the EQE and photovoltaic current density-voltage (J-V as a function of AOI in textured silicon solar cells with and without In NPs. We observed a reduction in optical reflectance and an increase in EQE when the cells textured with pyramidal structures were coated with In NPs. We also observed an impressive increase in the average weighted external quantum efficiency (∆EQEw and short-circuit current-density (∆Jsc in cells with In NPs when illuminated under a higher AOI. The ∆EQEw values of cells with In NPs were 0.37% higher than those without In NPs under an AOI of 0°, and 3.48% higher under an AOI of 75°. The ∆Jsc values of cells with In NPs were 0.50% higher than those without In NPs under an AOI of 0°, and 4.57% higher under an AOI of 75°. The application of In NPs clearly improved the light trapping effects. This can be attributed to the effects of plasmonic light-scattering over the entire wavelength range as well as an expanded angle of incident light.

  1. 'Incidence Of Dry Socket\\' In Benin City: Analysis Of 21 Cases ...

    African Journals Online (AJOL)

    Zinc oxide/Eugenol dressing was the mainstay of treatment after irrigation of the socket with normal saline. The low incidence of dry socket in this review shows that it is not a common complication of tooth extraction in our hospital. Keywords: Dry socket, incidence. Annals of Biomedical Science Vol. 2 (2) 2003: pp. 82-87 ...

  2. X-ray fluorescence spectrometers: a comparison of wavelength and energy dispersive instruments

    International Nuclear Information System (INIS)

    Slates, R.V.

    1977-11-01

    Wavelength dispersive and energy dispersive x-ray fluorescence spectrometers are compared. Separate sections are devoted to principles of operation, sample excitation, spectral resolution, and x-ray detection. Tabulated data from the literature are cited in the comparison of accuracy, precision, and detection limits. Spectral interferences and distortions are discussed. Advantages and limitations are listed for simultaneous wavelength dispersive spectrometers, sequential wavelength dispersive spectrometers, and Si(Li) energy dispersive spectrometers. Accuracy, precision, and detection limits are generally superior for wavelength dispersive spectrometers

  3. FOCUS: neutron time-of-flight spectrometer at SINQ: recent progress

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, S.; Mesot, J.; Holitzner, L. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Hempelmann, R. [Saarbruecken Univ. (Germany)

    1997-09-01

    At the Swiss neutron spallation source SINQ a time-of-flight spectrometer for cold neutrons is under construction. The design foresees a Hybrid solution combining a Fermi chopper with a doubly focusing crystal monochromator. During 1996 important progress has been made concerning the main spectrometer components such as the spectrometer housing and the detector system. (author) 2 figs., 3 refs.

  4. Upgrade of an old Raman Spectrometer

    DEFF Research Database (Denmark)

    Hansen, Susanne Brunsgaard; Berg, Rolf W.; Stenby, Erling Halfdan

    2004-01-01

    Improvement of a conventional Jeol Raman spectrometer with a single channel photo multiplier detector is described. New optical components (fibres, mirror, lens and CCD detector) have been chosen to design a high quality and easy-to-use instrument. Tests have shown that with this modified...... spectrometer Raman spectra can be acquired of a quality comparable to the spectra obtained previously, but the time needed to obtain a spectrum is markedly reduced. Selected test spectra and a simple calibration procedure to obtain the wavenumber values from the band CCD pixel position are presented....

  5. Spectrometer Baseline Control Via Spatial Filtering

    Science.gov (United States)

    Burleigh, M. R.; Richey, C. R.; Rinehart, S. A.; Quijada, M. A.; Wollack, E. J.

    2016-01-01

    An absorptive half-moon aperture mask is experimentally explored as a broad-bandwidth means of eliminating spurious spectral features arising from reprocessed radiation in an infrared Fourier transform spectrometer. In the presence of the spatial filter, an order of magnitude improvement in the fidelity of the spectrometer baseline is observed. The method is readily accommodated within the context of commonly employed instrument configurations and leads to a factor of two reduction in optical throughput. A detailed discussion of the underlying mechanism and limitations of the method are provided.

  6. A driving system for Moessbauer spectrometer

    International Nuclear Information System (INIS)

    Maslan, M.; Cholmeckij, A.; Evdokimov, V.; Misevic, O.; Fedorov, A.; Zak, D.

    1993-01-01

    The driving system of a Moessbauer spectrometer is described. The system comprises a minivibrator, a digital generator of the reference velocity signal, and circuits for controlling the vibrator. The reference velocity signal is stored by the control computer in an intermediate storage. The feedback in the control circuits includes correction for nonlinearity of the driving facility. A Moessbauer spectrometer which is equipped with this driving system exhibits a velocity scale nonlinearity below 0.1%. The resonance line width for sodium nitroprusside is 0.27 ± 0.01 mm/s. (author). 6 figs., 8 refs

  7. Opening the terahertz window on the OSIRIS spectrometer

    Directory of Open Access Journals (Sweden)

    Demmel F.

    2015-01-01

    Full Text Available A cooled and mechanically retractable beryllium filter has been installed and commissioned on the low-energy OSIRIS spectrometer at ISIS. This instrument development extends the energy-transfer range of the spectrometer up to ca. 20 meV (∼ 5 THz, leading to an excellent resolution at THz frequencies and substantial gains in detected flux relative to existing capabilities on the neighbouring IRIS spectrometer. Herein, we provide a concise account of this new capability for high-resolution neutron spectroscopy in the THz domain, as well as outline a number of ongoing and potential scientific opportunities in condensed-matter physics, chemistry, and materials science.

  8. Sensitivity and response time improvements in millimeter-wave spectrometers

    International Nuclear Information System (INIS)

    Kolbe, W.F.; Leskovar, B.

    1980-09-01

    A new version of a microwave spectrometer for the detection of gaseous pollutants and other atmospheric constituents is described. The spectrometer, which operates in the vicinity of 70 GHz, employs a Fabry-Perot resonator as a sample cell and uses superhetrodyne detection for high sensitivity. The spectrometer has been modified to incorporate a frequency doubler modulated at 30 MHz to permit operation with a single Gunn oscillator source. As a result, faster response time and somewhat greater sensitivity are obtained. The spectrometer is capable of detecting a minimum concentration of 1 ppM of SO 2 diluted in air with a 1 second time constant. For OCS diluted in air, the minimum detectable concentration is 800 ppB and with a 10 second time constant 300 ppB

  9. Spatial profile measurements of ion-confining potentials using novel position-sensitive ion-energy spectrometer arrays

    International Nuclear Information System (INIS)

    Yoshida, M.; Cho, T.; Hirata, M.; Ito, H.; Kohagura, J.; Yatsu, K.; Miyoshi, S.

    2003-01-01

    The first experimental demonstration of simultaneous measurements of temporally and spatially resolved ion-confining potentials phi c and end-loss-ion fluxes I ELA has been carried out during a single plasma discharge alone by the use of newly designed ion-energy-spectrometer arrays installed in both end regions of the GAMMA 10 tandem mirror. This position-sensitive ion-detector structure is proposed to obtain precise ion-energy spectra without any perturbations from simultaneously incident energetic electrons into the arrays. The relation between phi c and I ELA is physically interpreted in terms of Pastukhov's potential confinement theory. In particular, the importance of axisymmetric phi c formation is found for the plasma confinement

  10. Usefulness of normal saline for sealing the needle track after CT-guided lung biopsy

    International Nuclear Information System (INIS)

    Li, Y.; Du, Y.; Luo, T.Y.; Yang, H.F.; Yu, J.H.; Xu, X.X.; Zheng, H.J.; Li, B.

    2015-01-01

    Aim: To determine whether the use of normal saline for sealing the needle track can reduce the incidence of pneumothorax and chest tube placement after computed tomography (CT)-guided lung biopsy. Materials and methods: A prospective, randomised, controlled trial enrolling 322 patients was conducted. All patients were randomly assigned to one of two groups: those in whom the needle track was not sealed with normal saline (n=161, Group A) and those who did receive normal saline (n=161, Group B). CT-guided biopsy was performed with coaxial technique. Normal saline, which ranged from 1–3 ml, was injected while the trocar needle was being withdrawn. Patient characteristics, lesion, and procedure variables were analysed as potential risk variables for occurrence of pneumothorax and chest tube placement. Results: The incidence of pneumothorax was 26.1% in Group A and 6.2% in Group B (p<0.001). Nine patients in Group A and one patient in Group B required chest tube placement (p=0.010). Using multiple logistic regression analysis, smaller lesion size, greater needle–pleural angle, longer lesion–pleural distance, presence of emphysema, and no sealing the needle track with normal saline were significantly associated with an increased risk of pneumothorax, and that the latter three factors were also associated with an increased risk of pneumothorax requiring chest tube placement. Conlusion: Normal saline for sealing the needle track significantly reduces the incidence of pneumothorax and prevents subsequent chest tube placement after CT-guided lung biopsy. - Highlights: • Normal saline is an effective sealant for use in lung biopsy. • This technique reduced the incidence of pneumothorax and chest tube placement. • This technique should be recommended for CT-guided lung biopsy.

  11. Systematic Review and Meta-Analysis on Incidence of Altered Sensation of Mandibular Implant Surgery

    Science.gov (United States)

    Lin, Chia-Shu; Wu, Shih-Yun; Huang, Hsin-Yi; Lai, Yu-Lin

    2016-01-01

    Altered sensation (including paresthesia, dysesthesia and hypoesthesia) after mandibular implant surgery may indicate transient or permanent injury of the inferior alveolar nerve and the mental branch, and considerably lower patients’ satisfaction about the therapy. Previous studies have shown a great degree of variability on the incidence of altered sensation. We here reported the incidence of altered sensation after mandibular implant surgery based on a meta-analysis of 26 articles published between 1990.1.1 and 2016.1.1. Study quality and risk of bias was assessed and the studies with a lower score were excluded in the meta-analysis. Data synthesis was performed using the logistic-normal random-effect model. The meta-analyses revealed that the short-term (10 days after implant placement) and long-term (1 year after implant placement) incidence was 13% (95% CI, 6%-25%) and 3% (95% CI, 1%-7%), respectively. (2) For the patients who initially reported altered sensation, 80% (95% CI, 52%-94%) of them would return to normal sensation within 6 months after surgery, and 91% (95% CI, 78%-96%) of them would return to normal sensation one year after surgery. We concluded that dentist-patient communication about the risk of altered sensation is critical to treatment planning, since the short-term incidence of altered sensation is substantial (13%). When a patient reports altered sensation, regular assessment for 6 months would help tracing the changes of symptoms. In terms of long-term follow-up (1 year after surgery), the incidence is much lower (3%) and most patients (91%) would return to normal sensation. PMID:27100832

  12. Systematic Review and Meta-Analysis on Incidence of Altered Sensation of Mandibular Implant Surgery.

    Directory of Open Access Journals (Sweden)

    Chia-Shu Lin

    Full Text Available Altered sensation (including paresthesia, dysesthesia and hypoesthesia after mandibular implant surgery may indicate transient or permanent injury of the inferior alveolar nerve and the mental branch, and considerably lower patients' satisfaction about the therapy. Previous studies have shown a great degree of variability on the incidence of altered sensation. We here reported the incidence of altered sensation after mandibular implant surgery based on a meta-analysis of 26 articles published between 1990.1.1 and 2016.1.1. Study quality and risk of bias was assessed and the studies with a lower score were excluded in the meta-analysis. Data synthesis was performed using the logistic-normal random-effect model. The meta-analyses revealed that the short-term (10 days after implant placement and long-term (1 year after implant placement incidence was 13% (95% CI, 6%-25% and 3% (95% CI, 1%-7%, respectively. (2 For the patients who initially reported altered sensation, 80% (95% CI, 52%-94% of them would return to normal sensation within 6 months after surgery, and 91% (95% CI, 78%-96% of them would return to normal sensation one year after surgery. We concluded that dentist-patient communication about the risk of altered sensation is critical to treatment planning, since the short-term incidence of altered sensation is substantial (13%. When a patient reports altered sensation, regular assessment for 6 months would help tracing the changes of symptoms. In terms of long-term follow-up (1 year after surgery, the incidence is much lower (3% and most patients (91% would return to normal sensation.

  13. Optimum angle of incidence for monochromatic interference in transparent films on absorbing substrates

    International Nuclear Information System (INIS)

    Muller, R.H.; Sand, M.L.

    1980-01-01

    Angles of incidence for s- and p-polarized light have been computed and confirmed experimentally for which monochromatic interference in transparent thin films on absorbing substrates results in optimum interference fringe contrast (visibility=1). Under these angles of incidence and with polarized light, film thickness determinations which are not possible at normal incidence or with unpolarized light can be carried out by use of thin-film interference

  14. Extending The Useful Life Of Older Mass Spectrometers

    International Nuclear Information System (INIS)

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

    2010-01-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hunka, Deborah E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Austin, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    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).

  16. Cyclotrons as mass spectrometers

    International Nuclear Information System (INIS)

    Clark, D.J.

    1984-04-01

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

  17. Microprocessor monitored Auger spectrometer

    International Nuclear Information System (INIS)

    Sapin, Michel; Ghaleb, Dominique; Pernot, Bernard.

    1982-05-01

    The operation of an Auger spectrometer, used for studying surface impurity diffusion, has been fully automatized with the help of a microprocessor. The characteristics, performance and practical use of the system are described together with the main advantage for the experimentator [fr

  18. Uniformity of the soft-x-ray emissions from gold foils irradiated by OMEGA laser beams determined by a two-mirror normal-incidence microscope with multilayer coatings

    International Nuclear Information System (INIS)

    Seely, John F.; Boehly, Thomas; Pien, Gregory; Bradley, David

    1998-01-01

    A two-mirror normal-incidence microscope with multilayer coatings was used to image the soft-x-ray emissions from planar foils irradiated by OMEGA laser beams. The bandpass of the multilayer coatings was centered at a wavelength of 48.3 Angstrom (257-eV energy) and was 0.5 Angstrom wide. Five overlapping OMEGA beams, without beam smoothing, were typically incident on the gold foils. The total energy was 1500 J, and the focused intensity was 6x10 13 Wcm -2 . The 5.8x magnified images were recorded by a gated framing camera at various times during the 3-ns laser pulse. A pinhole camera imaged the x-ray emission in the energy range of >2 keV. On a spatial scale of 10 μm, it was found that the soft-x-ray images at 257 eV were quite uniform and featureless. In contrast, the hard-x-ray images in the energy range of >2 kev were highly nonuniform with numerous features of size 150 μm. copyright 1998 Optical Society of America

  19. LADEE Neutral Mass Spectrometer Data

    Data.gov (United States)

    National Aeronautics and Space Administration — This bundle contains the data collected by the Neutral Mass Spectrometer (NMS) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE)...

  20. A perturbed angular correlation spectrometer for material science ...

    Indian Academy of Sciences (India)

    A four-detector perturbed angular correlation (PAC) spectrometer has been developed with ultra-fast BaF2 detectors to acquire four coincidence spectra simultaneously, two at 180° and two at 90°. This spectrometer has double efficiency compared to that of a three-detector set-up. Higher efficiency is desirable for PAC ...

  1. Combined Raman/LIBS spectrometer elegant breadboard: built and tested - and flight model spectrometer unit

    Science.gov (United States)

    Ahlers, B.; Hutchinson, I.; Ingley, R.

    2017-11-01

    A spectrometer for combined Raman and Laser Induced Breakdown Spectroscopy (LIBS) is amongst the different instruments that have been pre-selected for the Pasteur payload of the ExoMars rover. It is regarded as a fundamental, next-generation instrument for organic, mineralogical and elemental characterisation of Martian soil, rock samples and organic molecules. Raman spectroscopy and LIBS will be integrated into a single instrument sharing many hardware commonalities [1]. The combined Raman / LIBS instrument has been recommended as the highest priority mineralogy instrument to be included in the rover's analytical laboratory for the following tasks: Analyse surface and sub-surface soil and rocks on Mars, identify organics in the search for life and determine soil origin & toxicity. The synergy of the system is evident: the Raman spectrometer is dedicated to molecular analysis of organics and minerals; the LIBS provides information on the sample's elemental composition. An international team, under ESA contract and with the leadership of TNO Science and Industry, has built and tested an Elegant Bread Board (EBB) of the combined Raman / LIBS instrument. The EBB comprises a specifically designed, extremely compact, spectrometer with high resolution over a large wavelength range, suitable for both Raman spectroscopy and LIBS measurements. The EBB also includes lasers, illumination and imaging optics as well as fibre optics for light transfer. A summary of the functional and environmental requirements together with a description of the optical design and its expected performance are described in [2]. The EBB was developed and constructed to verify the instruments' end-to-end functional performance with natural samples. The combined Raman / LIBS EBB realisation and test results of natural samples will be presented. For the Flight Model (FM) instrument, currently in the design phase, the Netherlands will be responsible for the design, development and verification of the

  2. BATS - Backscattering And Time-of-flight Spectrometer

    International Nuclear Information System (INIS)

    Van Eijck, L.; Seydel, T.; Frick, B.; Schober, H.

    2011-01-01

    The new backscattering spectrometer IN16b will go into commissioning end 2011, providing in its final state about ten times higher count rate than its predecessor, IN16. Here we propose to increase its dynamic range by a factor of 7 with the TOF mode extension, BATS. This will make IN16b the leading high resolution backscattering spectrometer for incoherent quasi-elastic and inelastic neutron scattering; it will be competitive to the coarser resolution inverted geometry backscattering spectrometers that are being brought online at spallation sources. The increased dynamic range will extend the scope of science addressed on IN16b, generating considerable potential in fields such as the hydrogen economy (proton conduction, fuel cells, hydrogen storage), soft matter, biology and nano-science (nano-scale confinement, functionalized polymers). Such a large impact can be achieved using only a moderate investment. (authors)

  3. The Raman Laser Spectrometer for the ExoMars Rover Mission to Mars

    Science.gov (United States)

    Rull, Fernando; Maurice, Sylvestre; Hutchinson, Ian; Moral, Andoni; Perez, Carlos; Diaz, Carlos; Colombo, Maria; Belenguer, Tomas; Lopez-Reyes, Guillermo; Sansano, Antonio; Forni, Olivier; Parot, Yann; Striebig, Nicolas; Woodward, Simon; Howe, Chris; Tarcea, Nicolau; Rodriguez, Pablo; Seoane, Laura; Santiago, Amaia; Rodriguez-Prieto, Jose A.; Medina, Jesús; Gallego, Paloma; Canchal, Rosario; Santamaría, Pilar; Ramos, Gonzalo; Vago, Jorge L.; RLS Team

    2017-07-01

    The Raman Laser Spectrometer (RLS) on board the ESA/Roscosmos ExoMars 2020 mission will provide precise identification of the mineral phases and the possibility to detect organics on the Red Planet. The RLS will work on the powdered samples prepared inside the Pasteur analytical suite and collected on the surface and subsurface by a drill system. Raman spectroscopy is a well-known analytical technique based on the inelastic scattering by matter of incident monochromatic light (the Raman effect) that has many applications in laboratory and industry, yet to be used in space applications. Raman spectrometers will be included in two Mars rovers scheduled to be launched in 2020. The Raman instrument for ExoMars 2020 consists of three main units: (1) a transmission spectrograph coupled to a CCD detector; (2) an electronics box, including the excitation laser that controls the instrument functions; and (3) an optical head with an autofocus mechanism illuminating and collecting the scattered light from the spot under investigation. The optical head is connected to the excitation laser and the spectrometer by optical fibers. The instrument also has two targets positioned inside the rover analytical laboratory for onboard Raman spectral calibration. The aim of this article was to present a detailed description of the RLS instrument, including its operation on Mars. To verify RLS operation before launch and to prepare science scenarios for the mission, a simulator of the sample analysis chain has been developed by the team. The results obtained are also discussed. Finally, the potential of the Raman instrument for use in field conditions is addressed. By using a ruggedized prototype, also developed by our team, a wide range of terrestrial analog sites across the world have been studied. These investigations allowed preparing a large collection of real, in situ spectra of samples from different geological processes and periods of Earth evolution. On this basis, we are working

  4. Modification of radiation-induced murine thymic lymphoma incidence by curcumin

    International Nuclear Information System (INIS)

    Dange, P.S.; Yadav, H.D.; Kumar, Vimalesh; Bhilwade, H.N.; Pandey, B.N.; Sarma, H.D.

    2017-01-01

    Curcumin is a known antioxidant, preventing radiation damage including carcinogenesis. However, concentration and feeding schedule of curcumin in modification of radiation induced thymic lymphoma incidence in vivo model has not been studied. We report here modification of incidence of γ-radiation-induced thymic lymphoma in mice fed with different doses of curcumin (0.05 to 1 %) in diet. Results: Female Swiss mice (6-8 weeks) fed with normal diet and exposed to 3 Gy whole body "6"0Co γ-irradiation (WBI) showed 85 % incidence of thymic lymphoma (TL) at 120 days post-irradiation. A concentration of 1 % curcumin was found the most effective in TL incidence prevention than other fed concentrations. The TL incidence was remarkably reduced when curcumin was fed to the mice before than after the radiation exposure. These results suggest modification of TL incidence by curcumin in irradiated mice involving DNA damage and apoptotic death mechanisms

  5. Two-lens spectrometer for. beta. polarimetry

    Energy Technology Data Exchange (ETDEWEB)

    Holdsworth, D; Paul, D [Toronto Univ., Ontario (Canada). Dept. of Physics

    1984-06-01

    A test spectrometer has been built having four degrees of freedom which have been varied to optimize the transmission in a configuration in which the image distance is large compared to the object distance. Iron-clad magnets of 15 cm effective inside diameter were used. Within the limits of the primary magnet field, the optimized transmission T (%. of 4..pi.. sr) increases as the source is advanced through the magnet towards the polarimeter, approximately as T=5.1 exp(zsub(s)/10.5), where zsub(s) is in cm, measured from the position of peak axial field. When the source-image distance is 1.8 m the optimum separation of the peak axial fields of the magnets is 67+-1 cm and the spectrometer transmission is the same for parallel or antiparallel fields. When operating in the optimum configuration, the spectrometer accepts particles with initial trajectories from 18/sup 0/ to 42/sup 0/ relative to the axis and delivers them at the target with half-angle of convergence less than 4.1/sup 0/.

  6. Portable spectrometer monitors inert gas shield in welding process

    Science.gov (United States)

    Grove, E. L.

    1967-01-01

    Portable spectrometer using photosensitive readouts, monitors the amount of oxygen and hydrogen in the inert gas shield of a tungsten-inert gas welding process. A fiber optic bundle transmits the light from the welding arc to the spectrometer.

  7. CHIRON – A new high resolution spectrometer for CTIO

    Directory of Open Access Journals (Sweden)

    Marcy G.W.

    2011-07-01

    Full Text Available Small telescopes can play an important role in the search for exoplanets because they offer an opportunity for high cadence observations that are not possible with large aperture telescopes. However, there is a shortage of high resolution spectrometers for precision Doppler planet searches. We report on an innovative design for CHIRON, an inexpensive spectrometer that we are building for the 1.5-m telescope at CTIO in Chile. The resolution will be R >80.000, the spectral format spanning 410 to 880 nm. The total throughput of the telescope and spectrometer will be better than 12%, comparable with the efficiency of state-of-the-art spectrometers. The design is driven by the requirements for precision Doppler searches for exoplanets using an iodine cell. The optical layout is a classical echelle with 140 mm beam size. The bench-mounted spectrometer will be fibre-fed followed by an image slicer. An apochromatic refractor is used as the camera. Image quality and throughput of the design are excellent over the full spectral range. Extensive use of commercially available components and avoidance of complicated custom optics are key for quick and resource-efficient implementation.

  8. Cassini Ion Mass Spectrometer Peak Calibrations from Statistical Analysis of Flight Data

    Science.gov (United States)

    Woodson, A. K.; Johnson, R. E.

    2017-12-01

    The Cassini Ion Mass Spectrometer (IMS) is an actuating time-of-flight (TOF) instrument capable of resolving ion mass, energy, and trajectory over a field of view that captures nearly the entire sky. One of three instruments composing the Cassini Plasma Spectrometer, IMS sampled plasma throughout the Kronian magnetosphere from 2004 through 2012 when it was permanently disabled due to an electrical malfunction. Initial calibration of the flight instrument at Southwest Research Institute (SwRI) was limited to a handful of ions and energies due to time constraints, with only about 30% of planned measurements carried out prior to launch. Further calibration measurements were subsequently carried out after launch at SwRI and Goddard Space Flight Center using the instrument prototype and engineering model, respectively. However, logistical differences among the three calibration efforts raise doubts as to how accurately the post-launch calibrations describe the behavior of the flight instrument. Indeed, derived peak parameters for some ion species differ significantly from one calibration to the next. In this study we instead perform a statistical analysis on 8 years of flight data in order to extract ion peak parameters that depend only on the response of the flight instrument itself. This is accomplished by first sorting the TOF spectra based on their apparent compositional similarities (e.g. primarily water group ions, primarily hydrocarbon ions, etc.) and normalizing each spectrum. The sorted, normalized data are then binned according to TOF, energy, and counts in order to generate energy-dependent probability density maps of each ion peak contour. Finally, by using these density maps to constrain a stochastic peak fitting algorithm we extract confidence intervals for the model parameters associated with various measured ion peaks, establishing a logistics-independent calibration of the body of IMS data gathered over the course of the Cassini mission.

  9. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, I.; Huppert, M.; Wörner, H. J., E-mail: hwoerner@ethz.ch [Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich (Switzerland); Brown, M. A. [Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich (Switzerland); Bokhoven, J. A. van [Institute for Chemical and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich (Switzerland); Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232 Villigen (Switzerland)

    2015-12-15

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

  10. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    International Nuclear Information System (INIS)

    Jordan, I.; Huppert, M.; Wörner, H. J.; Brown, M. A.; Bokhoven, J. A. van

    2015-01-01

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup

  11. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    Science.gov (United States)

    Jordan, I.; Huppert, M.; Brown, M. A.; van Bokhoven, J. A.; Wörner, H. J.

    2015-12-01

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

  12. A multi-parameter, acquisition system positron annihilation lifetime spectrometer

    International Nuclear Information System (INIS)

    Sharshar, T.

    2004-01-01

    A positron annihilation lifetime spectrometer employing a multi-parameter acquisition system has been prepared for various purposes such as the investigation and characterization of solid-state materials. The fast-fast coincidence technique was used in the present spectrometer with a pair of plastic scintillation detectors. The acquisition system is based on the Kmax software and on CAMAC modules. The data are acquired in event-by-event list mode. The time spectrum for the desired energy windows can be obtained by off-line data sorting and analysis. The spectrometer for event-by-event data acquisition is an important step to construct a positron age-momentum correlation (AMOC) spectrometer. The AMOC technique is especially suited for the observation of positron transitions between different states during their lifetime. The system performance was tested and the results were presented and discussed

  13. The development for small scale soft X-ray spectrometer

    International Nuclear Information System (INIS)

    Sun Kexu; Jiang Shaoen; Yi Rongqing; Cui Yanli

    2004-12-01

    For the development of small-scale soft X-ray spectrometer, first, some small-scale soft X-ray detection elements are developed, it is included GaAs irradiated with neutron, GaAs irradiated with proton, multi-layer mirror, plane mirror and small scale X-ray diode et al. Soft X-ray spectrometers built of multi-layer mirror-GaAs (with neutron irradiation), and plane mirror-small-scale XRD, and plane mirror-GaAs (with proton irradiation) are prepared. These spectrometers are examined in Shen Guang-II laser facility, and some external estimation are given. (authors)

  14. The OVIRS Visible/IR Spectrometer on the OSIRIS-Rex Mission

    Science.gov (United States)

    Reuter, D. C.; Simon-Miller, A. A.

    2012-01-01

    The OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security Regolith Explorer) Mission is a planetary science mission to study, and return a sample from, the carbonaceous asteroid 1999 RQ-36. The third mission selected under NASA's New Frontiers Program, it is scheduled to be launched in 2016. It is led by PI Dante Lauretta at the University of Arizona and managed by NASA's Goddard Space Flight Center. The spacecraft and the asteroid sampling mechanism, TAGSAM (Touch-And-Go Sample Acquisition Mechanism) will be provided by Lockheed Martin Space Systems. Instrumentation for studying the asteroid include: OCAMS (the OSIRIS-REx Camera Suite), OLA (the OSIRIS-REx Laser Altimeter, a scanning LIDAR), OTES (The OSIRIS-REx Thermal Emission Spectrometer, a 4-50 micron point spectrometer) and OVIRS (the OSIRIS-REx Visible and IR Spectrometer, a 0.4 to 4.3 micron point spectrometer). The payload also includes REXIS (the Regolith X-ray Imaging Spectrometer) a student provided experiment. This paper presents a description of the OVIRS instrument.

  15. Measurements of Pair Production Under Channelling Conditions by 70-180 GeV Photons Incident on Single Crystals

    CERN Multimedia

    2002-01-01

    This experiment will use the WA69 set-up to deliver a tagged photon beam in the energy range from 15~GeV to 150~GeV with a total angular spread of about @M~0.5~mrad. The incident photon direction is known to about 35~@mrad through the direction of the emitting electron. The photon beam is incident on an about 1~mm thick Ge single crystal in order to investigate pair production in single crystals. Above a certain energy threshold photons incident along crystal axis will show strongly increased pair production yi - the so-called .us Channelling Pair Production (ChPP). The produced pairs are analyzed in the @W-spectrometer. The large spread in incident photon angles offers an excellent opportunity to investigate in one single experiment the pair production in an angular region around a crystal axes and thereby compare ChPP with coherent (CPP) and incoherent (ICPP) processes. The very abrupt onset of ChPP (around threshold) will be measured and give a crucial test of the theoretical calculations. The differential...

  16. Development of cold neutron spectrometers

    International Nuclear Information System (INIS)

    Lee, Changhee; Lee, C. H.; So, J. Y.; Park, S.; Han, Y. S.; Cho, S. J.; Moon, M. K.; Choi, Y. H.; Sun, G. M.

    2012-03-01

    □ Cold Neutron Triple Axsis Spectrometer (Cold-TAS) Development Ο Fabrication and Installation of the Major Cold-TAS Components Ο Performance Test of the Cold-TAS □ Cold Neutron Time-of-Flight Spectrometer(DC-TOF) Development Ο Fabrication of the Major DC-TOF Components Ο Development DC-TOF Data Reduction Software □ Expected Contribution The two world-class inelastic neutron scattering instruments measure atomic or molecular scale dynamics of meV energy range. This unprecedented measurement capability in the country will enable domestic and international scientists to observe new phenomena in their materials research to obtain world class results. Especially those who work in the fields of magnetic properties of superconductors and multiferroics, molecular dynamics, etc. will get more benefit from these two instruments

  17. GEANT Monte Carlo simulations for the GREAT spectrometer

    International Nuclear Information System (INIS)

    Andreyev, A.N.; Butler, P.A.; Page, R.D.; Appelbe, D.E.; Jones, G.D.; Joss, D.T.; Herzberg, R.-D.; Regan, P.H.; Simpson, J.; Wadsworth, R.

    2004-01-01

    GEANT Monte Carlo simulations for the recently developed GREAT spectrometer are presented. Some novel applications of the spectrometer for γ-ray, conversion-electron and β-decay spectroscopy are discussed. The conversion-electron spectroscopy of heavy nuclei with strongly converted transitions and the extension of the recoil decay tagging method to β-decaying nuclei are considered in detail

  18. Theoretical resolving power of a radiofrequency mass spectrometer

    International Nuclear Information System (INIS)

    Coc, A.; Le Gac, R.; Saint Simon, M. de; Thibault, C.; Touchard, F.

    1988-01-01

    Radiofrequency mass spectrometers of L.G. Smith's type can reach a resolving power of 10 6 -10 7 and a precision of 10 -9 -10 -10 . The resolving power, shape of peaks and limitations are described. As an example, the spectrometer to be used in an experiment aimed at measuring the anti p/p mass ratio is considered. (orig.)

  19. The incidence of spondylolysis and spondylolisthesis in children with osteogenesis imperfecta.

    Science.gov (United States)

    Hatz, Daniel; Esposito, Paul W; Schroeder, Bruce; Burke, Bridget; Lutz, Richard; Hasley, Brian P

    2011-09-01

    Spondylolysis and spondylolisthesis are common abnormalities of the lumbar spine. The incidence of these diagnoses is recognized in the healthy population. However, their incidence in osteogenesis imperfecta (OI) patients is less well defined. This is a retrospective radiographic review of patients treated in the OI clinic from a single institution. Lateral radiographs were reviewed on all available patients to assess the incidence of spondylolysis and spondylolisthesis in this patient population. The morphology of the pedicle and pars interarticularis was also evaluated to identify any abnormalities or dysplasia of these structures. One hundred ten of the 139 patients treated in the OI clinic met the inclusion criteria for this study. Of these patients, 79% (87 of 110) were ambulatory. The overall incidence of spondylolysis in this pediatric OI population was found to be 8.2% (9 of 110) at an average age of 7.5 years. The incidence of spondylolisthesis was 10.9% (12 of 110) at an average age of 6.5 years with 75% (3 of 12) being isthmic type and 25% (3 of 12) dysplastic. The combined incidence of spondylolysis and spondylolisthesis was 19.2%. Incidentally, the pedicle length was noted to be elongated in 40.0% (44 of 110) of this OI population. This study found that the incidence of spondylolysis in a group of children with OI was much higher than in the normal pediatric population, which has been reported to be 2.6% to 4.0%. This incidence was also found to be higher than previously reported incidence of spondylolysis in OI patients (5.3%). The incidence of spondylolisthesis was also found to be much higher than that of the normal pediatric population (4.2%). It is important to recognize this higher incidence of these abnormalities and to anticipate future associated symptoms and potential worsening listhesis that can clinically affect the lifestyles of these children and potentially require surgical treatment. The clinical significance of these findings will

  20. Noise considerations in millimeter-wave spectrometers

    International Nuclear Information System (INIS)

    Zoellner, W.D.; Kolbe, W.F.; Leskovar, B.

    1978-12-01

    An improved version of a microwave spectrometer operating in the vicinity of 70 GHz is described. The spectrometer, which incorporates a Fabry-Perot resonator and superheterodyne detection for high sensitivity is designed for the detection of gaseous pollutants and other atmospheric constituents. The instrument is capable of detecting polar molecules with absorption coefficients as small as 2 x 10 -9 cm -1 . For sulphur dioxide diluted in air, this sensitivity corresponds to a detection limit of 1.2 ppm without preconcentration and with a time constant of 1 second. Measurements and analysis of the noise contributions limiting the sentivity are presented

  1. Streaked, x-ray-transmission-grating spectrometer

    International Nuclear Information System (INIS)

    Ceglio, N.M.; Roth, M.; Hawryluk, A.M.

    1981-08-01

    A free standing x-ray transmission grating has been coupled with a soft x-ray streak camera to produce a time resolved x-ray spectrometer. The instrument has a temporal resolution of approx. 20 psec, is capable of covering a broad spectral range, 2 to 120 A, has high sensitivity, and is simple to use requiring no complex alignment procedure. In recent laser fusion experiments the spectrometer successfully recorded time resolved spectra over the range 10 to 120 A with a spectral resolving power, lambda/Δlambda of 4 to 50, limited primarily by source size and collimation effects

  2. Highly effective portable beta spectrometer for precise depth selective electron Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Aldiyarov, N.U.; Kadyrzhanov, K.K.; Seytimbetov, A.M.; Zhdanov, V.S.

    2007-01-01

    Full text: More broad application of the nuclear-physical method of precise Depth Selective Electron Moessbauer Spectroscopy (DS EMS) is limited by insufficient accessibility of highly-effective beta spectrometers with acceptable resolution. It should be mentioned that the method DS EMS is realized at a combined installation that consists of a highly-effective beta spectrometer and a conventional portable nuclear gamma-resonance spectrometer. Yet few available beta spectrometers have sophisticated design and controlling; in most cases they are cumbersome. All the attempts to simplify beta spectrometers resulted in noticeable worsening of depth resolution for the DS EMS method making the measurements non precise. There is currently an obvious need in a highly-effective portable easily controlled beta spectrometer. While developing such portable beta spectrometer, it is more promising to use as basis a simpler spectrometer, which has ratio of sample size to spectrometer size of about five times. The paper presents an equal-arm version of a highly-effective portable beta spectrometer with transverse heterogeneous sector magnetic field that assures double focusing. The spectrometer is equipped with a large-area non-equipotential source (a sample under investigation) and a position-sensitive detector. This portable spectrometer meets all requirements for achievement of the DS EMS depth resolution close to the physical limit and demonstrates the following main characteristics: equilibrium orbit radius ρ 0 = 80 mm, instrumental energy resolution 0.6 % at solid angle 1 % of 4π steradian, area of non-equipotential source ∼ 80 mm 2 , registration by position-sensitive detector of ∼ 10 % of the energy interval. Highly-effective portable beta spectrometer assures obtaining Moessbauer data with depth resolution close to physical limit of the DS EMS method. So in measurements at conversion and Auger electrons with energies of about units of keV and above, the achieved

  3. Development of gamma spectrometer using silicon photomultiplier (SiPM)

    International Nuclear Information System (INIS)

    Kim, Chan Kyu

    2011-02-01

    Gamma spectroscopy is used to determine the identity and quantity of gamma-emitters in nuclear physics, geochemistry and astrophysics. The scintillation detectors are being used as a gamma spectrometer generally, because of their higher gamma-ray detection efficiency and cheaper price than germanium semi-conductor detectors. A typical scintillation detector is composed of a scintillator, a window, and a photodetector. The photomultiplier (PM) tube has been the most widely used as a photodetector because of its advantages like high sensitivity, high signal-to-noise ratio, and wide dynamic range. Recently, the Silicon Photomultiplier (SiPM) is being studied as a substitute of PM tube. The SiPM has almost same performance compared to PM tube but it has additional advantages; low operating voltage, small volume, and cheap production cost. In this research, the gamma spectrometer using SiPM instead of PM tube is developed. The use of SiPM as a photodetector makes the gamma spectrometer smaller, cheaper, easier to use. For photon transport and collection from the large area scintillator to the small area SiPM, a light guide is applied in this gamma spectrometer system. Before fabrication of light guide, DETECT simulation is performed to study and prospect characteristics of light guide structure. And actual light guides are fabricated on the basis of this simulation result. Poly(methyl methacrylate) (PMMA) is chosen as material of light guide, 5 sample light guides are fabricated in different lengths and coatings. As a scintillator crystal, same NaI(Tl) crystal is chosen. For measurement and analysis of gamma spectrometer system, 3 gamma spectrometer systems are composed: PM tube-based system, PM tube-based system with the light guide, SiPM-based system with the light guide. Through comparison between the results of each gamma spectrometer, the performances of gamma spectrometer system are analyzed by each component. Measurement results of the second system is well

  4. Elements of Tiny Plasma Spectrometers

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to advance major elements of a miniaturized plasma spectrometer for flight on future missions. This type of instrument has been developed and successfully...

  5. The Lise spectrometer at Ganil

    International Nuclear Information System (INIS)

    Saint-Laurent, M.G.

    1986-08-01

    The doubly achromatic spectrometer LISE is available at the french national heavy ion accelerator GANIL. Experimental results, obtained in radioactive beam production and search for new exotic nuclei are briefly reported

  6. The OPERA magnetic spectrometer

    CERN Document Server

    Ambrosio, M; Dusini, S; Dulach, B; Fanin, C; Felici, G; Corso, F D; Garfagnini, A; Grianti, F; Gustavino, C; Monacelli, P; Paoloni, A; Stanco, L; Spinetti, M; Terranova, F; Votano, L

    2004-01-01

    The OPERA neutrino oscillation experiment foresees the construction of two magnetized iron spectrometers located after the lead-nuclear emulsion targets. The magnet is made up of two vertical walls of rectangular cross section connected by return yokes. The particle trajectories are measured by high precision drift tubes located before and after the arms of the magnet. Moreover, the magnet steel is instrumented with Resistive Plate Chambers that ease pattern recognition and allow a calorimetric measurement of the hadronic showers. In this paper we review the construction of the spectrometers. In particular, we describe the results obtained from the magnet and RPC prototypes and the installation of the final apparatus at the Gran Sasso laboratories. We discuss the mechanical and magnetic properties of the steel and the techniques employed to calibrate the field in the bulk of the magnet. Moreover, results of the tests and issues concerning the mass production of the Resistive Plate Chambers are reported. Final...

  7. The SPEDE electron spectrometer

    CERN Document Server

    O'Neill, George

    This thesis presents SPEDE (SPectrometer for Electron DEtection) and documents its construction, testing and performance during commissioning at Jyvaskyla, Finland, before deployment at the HIE-ISOLDE facility at CERN coupled with the MINIBALL array to perform in-beam electron-gamma spectroscopy using post-accelerated radioactive ion beams. Commissioning experiments took place in two two-day stints during spring 2015, coupled with several JUROGAMII gamma-detectors. This spectrometer will help aid in fully understanding exotic regions of the nuclear chart such as regions with a high degree of octupole deformation, and in those nuclei exhibiting shape coexistence. For the rst time, electron spectroscopy has been performed at the target position from states populated in accelerated nuclei via Coulomb excitation. The FWHM of SPEDE is approximately 7 keV at 320 keV, and Doppler correction was possible to improve Doppler broadened peaks. The results are intended to give the reader a full understanding of the dete...

  8. A low-volume cavity ring-down spectrometer for sample-limited applications

    Science.gov (United States)

    Stowasser, C.; Farinas, A. D.; Ware, J.; Wistisen, D. W.; Rella, C.; Wahl, E.; Crosson, E.; Blunier, T.

    2014-08-01

    In atmospheric and environmental sciences, optical spectrometers are used for the measurements of greenhouse gas mole fractions and the isotopic composition of water vapor or greenhouse gases. The large sample cell volumes (tens of milliliters to several liters) in commercially available spectrometers constrain the usefulness of such instruments for applications that are limited in sample size and/or need to track fast variations in the sample stream. In an effort to make spectrometers more suitable for sample-limited applications, we developed a low-volume analyzer capable of measuring mole fractions of methane and carbon monoxide based on a commercial cavity ring-down spectrometer. The instrument has a small sample cell (9.6 ml) and can selectively be operated at a sample cell pressure of 140, 45, or 20 Torr (effective internal volume of 1.8, 0.57, and 0.25 ml). We present the new sample cell design and the flow path configuration, which are optimized for small sample sizes. To quantify the spectrometer's usefulness for sample-limited applications, we determine the renewal rate of sample molecules within the low-volume spectrometer. Furthermore, we show that the performance of the low-volume spectrometer matches the performance of the standard commercial analyzers by investigating linearity, precision, and instrumental drift.

  9. Semiconductor X-ray spectrometer with light feedback

    International Nuclear Information System (INIS)

    Zubareva, A.M.; Iliev, S.; Kushniruk, V.F.; Rykhlyuk, A.V.; Subbotin, V.G.; Kharitonov, Yu.P.

    1978-01-01

    An X-ray spectrometer has been designed consisting of a preamplifier with light pulse feedback, and a Si (Li) detector. The electric(FET) circuit is given of the preamplifier designed on field effect transistors. An identification is made of the types of noises of a sink current of 7.5 mA. It is established that a significant part of the total noise comes from the detector-FET system, and white noise from leakage current in the detector. The use in the spectrometer of the preamplifier with light pulse feedback enables the white noise to be reduced to 40-45 eV with a detector leakage current of 10 -13 A. A decrease in the noise of the detector-FET system is only possible owing to the improved technology in the manufacture of FET's. The energy resolution of the spectrometer for the 5.9 keV line is 168 eV

  10. Partial pressure measurements with an active spectrometer

    International Nuclear Information System (INIS)

    Brooks, N.H.; Jensen, T.H.; Colchin, R.J.; Maingi, R.; Wade, M.R.; Finkenthal, D.F.; Naumenko, N.; Tugarinov, S.

    1998-07-01

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

  11. Tantalum films with well-controlled roughness grown by oblique incidence deposition

    Science.gov (United States)

    Rechendorff, K.; Hovgaard, M. B.; Chevallier, J.; Foss, M.; Besenbacher, F.

    2005-08-01

    We have investigated how tantalum films with well-controlled surface roughness can be grown by e-gun evaporation with oblique angle of incidence between the evaporation flux and the surface normal. Due to a more pronounced shadowing effect the root-mean-square roughness increases from about 2 to 33 nm as grazing incidence is approached. The exponent, characterizing the scaling of the root-mean-square roughness with length scale (α), varies from 0.75 to 0.93, and a clear correlation is found between the angle of incidence and root-mean-square roughness.

  12. Computer simulation and data compilation of sputtering yield by hydrogen isotopes ({sup 1}H{sup +}, {sup 2}D{sup +}, {sup 3}T{sup +}) and helium ({sup 4}He{sup +}) ion impact from monatomic solids at normal incidence

    Energy Technology Data Exchange (ETDEWEB)

    Yamamura, Yasunori; Sakaoka, Kazuho; Tawara, Hiro

    1995-10-01

    The ion-induced sputtering yields from monatomic solids at normal incidence are presented graphically for light-ion ({sup 1}H{sup +}, {sup 2}D{sup +}, {sup 3}T{sup +}, {sup 4}He{sup +}) bombardment on various target materials as a function of the incident ion energy. To supplement the experimental data, the sputtering yields are calculated by the Monte Carlo simulation code ACAT for all possible light ion-target combinations. Each graph shows the available experimental and ACAT data points, together with the sputtering yield calculated by the Yamamura and Tawara empirical formula. (author).

  13. Expert systems technology applied to instrument operation and data acquisition of a triple quadrupole mass spectrometer (TQMS)

    International Nuclear Information System (INIS)

    Wong, C.M.

    1984-01-01

    This presentation covers the work done at Lawrence Livermore National Laboratory by some computer programmers and analytical chemists specializing in mass spectrometry to develop an expert system for real-time tuning and optimization of operations of a triple quadrupole mass spectrometer (TQMS). This capability is important to increase the sensitivity possible for selected compounds throughout the entire mass range of the instrument, rather than settling for the traditional normalized calibration which lowers sensitivity at both ends of the mass scale

  14. High-resolution spectrometer at PEP

    International Nuclear Information System (INIS)

    Weiss, J.M.; HRS Collaboration.

    1982-01-01

    A description is presented of the High Resolution Spectrometer experiment (PEP-12) now running at PEP. The advanced capabilities of the detector are demonstrated with first physics results expected in the coming months

  15. An improved computer controlled triple-axis neutron spectrometer

    International Nuclear Information System (INIS)

    Cooper, M.J.; Hall, J.W.; Hutchings, M.T.

    1975-07-01

    A description is given of the computer-controlled triple-axis neutron spectrometer installed at the PLUTO reactor at Harwell. The reasons for an nature of recent major improvements are discussed. Following a general description of the spectrometer, details are then given of the new computerised control system, including the functions of the various programs which are now available to the user. (author)

  16. Automation, development and performance of a photoacoustic spectrometer

    International Nuclear Information System (INIS)

    Cavalheiro, F.R.F.

    1985-01-01

    This work consists in the development of a circuit to interface a photoacoustic spectrometer with a microcomputer. The obtained spectra are identical to those obtained in commercial photoacoustic spectrometers. The system permits a great versatility and it has possibilities to automatize other types of experiments. The system can be duplicated from national components and at a relatively low coast. (author)

  17. A new small-angle neutron scattering spectrometer at China Mianyang research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Mei, E-mail: pm740509@163.com; Sun, Liangwei; Chen, Liang; Sun, Guangai; Chen, Bo; Xie, Chaomei; Xia, Qingzhong; Yan, Guanyun; Tian, Qiang; Huang, Chaoqiang; Pang, Beibei; Zhang, Ying; Wang, Yun; Liu, Yaoguang; Kang, Wu; Gong, Jian

    2016-02-21

    A new pinhole small-angle neutron scattering (SANS) spectrometer, installed at the cold neutron source of the 20 MW China Mianyang Research Reactor (CMRR) in the Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, has been put into use since 2014. The spectrometer is equipped with a multi-blade mechanical velocity selector, a multi-beam collimation system, and a two-dimensional He-3 position sensitive neutron detector. The q-range of the spectrometer covers from 0.01 nm{sup −1} to 5.0 nm{sup −1}. In this paper, the design and characteristics of the SANS spectrometer are described. The q-resolution calculations, together with calibration measurements of silver behenate and a dispersion of nearly monodisperse poly-methyl-methacrylate nanoparticles indicate that our SANS spectrometer has a good performance and is now in routine service. - Highlights: • A new SANS spectrometer has been put into use since 2014 in China. • One MBR selector possesses a higher resolution compared with traditional selector is used. • The spectrometer has a good performance and is now in routinely service.

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

    International Nuclear Information System (INIS)

    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.

    2010-01-01

    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.

  19. Compact terahertz spectrometer based on disordered rough surfaces

    Science.gov (United States)

    Yang, Tao; Jiang, Bing; Ge, Jia-cheng; Zhu, Yong-yuan; Li, Xing-ao; Huang, Wei

    2018-01-01

    In this paper, a compact spectrometer based on disordered rough surfaces for operation in the terahertz band is presented. The proposed spectrometer consists of three components, which are used for dispersion, modulation and detection respectively. The disordered rough surfaces, which are acted as the dispersion component, are modulated by the modulation component. Different scattering intensities are captured by the detection component with different extent of modulation. With a calibration measurement process, one can reconstruct the spectra of the probe terahertz beam by solving a system of simultaneous linear equations. A Tikhonov regularization approach has been implemented to improve the accuracy of the spectral reconstruction. The reported broadband, compact, high-resolution terahertz spectrometer is well suited for portable terahertz spectroscopy applications.

  20. A Shuttle Upper Atmosphere Mass Spectrometer /SUMS/ experiment

    Science.gov (United States)

    Blanchard, R. C.; Duckett, R. J.; Hinson, E. W.

    1982-01-01

    A magnetic mass spectrometer is currently being adapted to the Space Shuttle Orbiter to provide repeated high altitude atmosphere data to support in situ rarefied flow aerodynamics research, i.e., in the high velocity, low density flight regime. The experiment, called Shuttle Upper Atmosphere Mass Spectrometer (SUMS), is the first attempt to design mass spectrometer equipment for flight vehicle aerodynamic data extraction. The SUMS experiment will provide total freestream atmospheric quantitites, principally total mass density, above altitudes at which conventional pressure measurements are valid. Experiment concepts, the expected flight profile, tradeoffs in the design of the total system and flight data reduction plans are discussed. Development plans are based upon a SUMS first flight after the Orbiter initial development flights.

  1. High flux polarized neutrons triple-axis spectrometer: 2T (LLB-Saclay)

    International Nuclear Information System (INIS)

    Bourges, Ph.; Hennion, B.; Sidis, Y.; Boutrouille, Ph.; Baroni, P.

    1999-01-01

    A description of the performance of the newly designed thermal beam triple-axis spectrometer, 2T at LLB (Saclay) is given. The beam tube will be increased to 50 x 120 mm 2 (HxV) before the monochromator. A gain of about a factor 2 on the neutron flux at the monitor position is expected after this operation, scheduled on April/May 1999. Polarized neutrons beam option will be installed on this triple axis. The polarization is obtained using high quality heusler crystals recently grown at ILL. The size of both heusler monochromator and analyzer have been chosen to fully cover the beam size. The monochromator (analyzer) will be equipped with a vertical (horizontal) curvature. The flux of the polarized beam on the detector is then expected to be 5 times better than IN20 at ILL (best existing polarized neutrons triple-axis on thermal beam) with incident energy upto 75 MeV. (author)

  2. Inficon Transpector MPH Mass Spectrometer Random Vibration Test Report

    Science.gov (United States)

    Santiago-Bond, Jo; Captain, Janine

    2015-01-01

    The purpose of this test report is to summarize results from the vibration testing of the INFICON Transpector MPH100M model Mass Spectrometer. It also identifies requirements satisfied, and procedures used in the test. As a payload of Resource Prospector, it is necessary to determine the survivability of the mass spectrometer to proto-qualification level random vibration. Changes in sensitivity of the mass spectrometer can be interpreted as a change in alignment of the instrument. The results of this test will be used to determine any necessary design changes as the team moves forward with flight design.

  3. Design of airborne imaging spectrometer based on curved prism

    Science.gov (United States)

    Nie, Yunfeng; Xiangli, Bin; Zhou, Jinsong; Wei, Xiaoxiao

    2011-11-01

    A novel moderate-resolution imaging spectrometer spreading from visible wavelength to near infrared wavelength range with a spectral resolution of 10 nm, which combines curved prisms with the Offner configuration, is introduced. Compared to conventional imaging spectrometers based on dispersive prism or diffractive grating, this design possesses characteristics of small size, compact structure, low mass as well as little spectral line curve (smile) and spectral band curve (keystone or frown). Besides, the usage of compound curved prisms with two or more different materials can greatly reduce the nonlinearity inevitably brought by prismatic dispersion. The utilization ratio of light radiation is much higher than imaging spectrometer of the same type based on combination of diffractive grating and concentric optics. In this paper, the Seidel aberration theory of curved prism and the optical principles of Offner configuration are illuminated firstly. Then the optical design layout of the spectrometer is presented, and the performance evaluation of this design, including spot diagram and MTF, is analyzed. To step further, several types of telescope matching this system are provided. This work provides an innovational perspective upon optical system design of airborne spectral imagers; therefore, it can offer theoretic guide for imaging spectrometer of the same kind.

  4. Beam analysis spectrometer for relativistic heavy ions

    International Nuclear Information System (INIS)

    Schimmerling, W.; Subramanian, T.S.; McDonald, W.J.; Kaplan, S.N.; Sadoff, A.; Gabor, G.

    1983-01-01

    A versatile spectrometer useful for measuring the mass, charge, energy, fluence and angular distribution of primaries and fragments associated with relativistic heavy ion beams is described. The apparatus is designed to provide accurate physical data for biology experiments and medical therapy planning as a function of depth in tissue. The spectrometer can also be used to measure W, the average energy to produce an ion pair, range-energy, dE/dx, and removal cross section data of interest in nuclear physics. (orig.)

  5. Electron spectrometers with internal conversion

    International Nuclear Information System (INIS)

    Suita, J.C.; Lemos Junior, O.F.; Auler, L.T.; Silva, A.G. da

    1981-01-01

    The efforts that the Department of Physics (DEFI) of Institute of Nuclear Engineering (IEN) are being made aiming at adjusting the electron spectrometers with internal conversion to its necessity, are shown. (E.G.) [pt

  6. Exploiting a Transmission Grating Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ronald E. Bell

    2004-12-08

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

  7. Exploiting a Transmission Grating Spectrometer

    International Nuclear Information System (INIS)

    Bell, Ronald E.

    2004-01-01

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

  8. Polarized neutron spectrometer

    International Nuclear Information System (INIS)

    Abov, Yu.G.; Novitskij, V.V.; Alfimenkov, V.P.; Galinskij, E.M.; Mareev, Yu.D.; Pikel'ner, L.B.; Chernikov, A.N.; Lason', L.; Tsulaya, V.M.; Tsulaya, M.I.

    2000-01-01

    The polarized neutron spectrometer, intended for studying the interaction of polarized neutrons with nuclei and condensed media in the area of energies from thermal up to several electron-volt, is developed at the IBR-2 reactor (JINR, Dubna). Diffraction on the Co(92%)-Fe(8%) magnetized monocrystals is used for the neutron polarization and polarization analysis. The neutron polarization within the whole energy range equals ∼ 95% [ru

  9. Description of the double Compton spectrometer at Mayence MPI

    International Nuclear Information System (INIS)

    Borchert, H.; Ziegler, B.; Gimm, H.; Zieger, A.; Hughes, R.J.; Ahrens, J.

    1977-01-01

    The double Compton spectrometer of the Laboratories of the Mayence Linear Accelerator consists in two identical magnetic spectrometers, in which the electron scattered forwards by photons through a Compton process, are detected. The spectrometers have been built to detect 10-350 MeV photons and, as they involve thin Compton targets, their effect on the photon flux is negligible. They are put in cascade inside a well collimated bremsstrahlung beam. A thick absorbing target (max. thickness 2m) can be inserted inside the beam. The facility is outlined, some special properties of the accelerator and the bremsstrahlung beam are given. The properties of a Compton spectrometer involving eleven detectors are given by eleven response functions giving the relations between the photon flux impinging the Compton target and the counting rates of the detectors for a given adjustment of the magnets. A Monte-Carlo method is used for the calculation together with analytical methods neglecting the multiple scattering effects [fr

  10. Optimal shape of a cold-neutron triple-axis spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Lefmann, K., E-mail: lefmann@fys.ku.d [Nanoscience and eScience Centers, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen O (Denmark); European Spallation Source, University of Lund, St. Algatan 4, Lund (Sweden); Filges, U. [Laboratory for Development and Methods, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Treue, F. [Nanoscience and eScience Centers, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen O (Denmark); Kirkensgard, J.J.K. [Institute of Nature and Models, Roskilde University (Denmark); Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen (Denmark); Plesner, B. [Institute of Nature and Models, Roskilde University (Denmark); Hansen, K.S. [Institute of Nature and Models, Roskilde University (Denmark); Mid-Greenland High School, Nuuk, Greenland (Denmark); Kleno, K.H. [Nanoscience and eScience Centers, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen O (Denmark); European Spallation Source, University of Lund, St. Algatan 4, Lund (Sweden)

    2011-04-01

    We have performed a McStas optimization of the primary spectrometer for a generic 40 m long, cold-neutron triple-axis spectrometer with a doubly focusing monochromator. The optimal design contains an elliptically focusing guide, a virtual source point before a low-grade PG monochromator, and non-equidistant focusing at the monochromator. The flux at 5 meV shows a gain factor 12 over the 'classical' design with a straight 12x3cm{sup 2}, m=2 guide and a vertically focusing PG monochromator. In addition, the energy resolution was found to be improved. This unexpectedly large design improvement agrees with the Liouville theorem and can be understood as the product of many smaller gain factors, combined with a more optimal utilization of the beam divergence within the guide. Our results may be relevant for a possible upgrade of a number of cold-neutron triple-axis spectrometers-and for a possible triple-axis spectrometer at the European Spallation Source.

  11. Single spectrometer station for neutrino-tagging

    International Nuclear Information System (INIS)

    Nedyalkov, I.P.

    1984-01-01

    A neutrino tagging station built with respect to the following scheme is proposed. A beam of muons and kaons passes through a magnetic spectrometer, where the energy of each particle is measured. There are coordinate detectors behind the spectrometer in several planes, where the direction of the trajectory of a given particle is determined. Thus, mesons enter the decay point wth the known 4-momentum. Behind the decay point the direction of μ-meson generated by the decay of parent mesons is measured. It is shown that information is sufficient for determining the kind of parent particle (pion or kaon), the energy and the direction of trajectory of the neutrino

  12. Linear Fresnel Spectrometer Chip with Gradient Line Grating

    Science.gov (United States)

    Choi, Sang Hyouk (Inventor); Park, Yeonjoon (Inventor)

    2015-01-01

    A spectrometer that includes a grating that disperses light via Fresnel diffraction according to wavelength onto a sensing area that coincides with an optical axis plane of the grating. The sensing area detects the dispersed light and measures the light intensity associated with each wavelength of the light. Because the spectrometer utilizes Fresnel diffraction, it can be miniaturized and packaged as an integrated circuit.

  13. Fast infrared array spectrometer with a thermoelectrically cooled 160-element PbSe detector

    International Nuclear Information System (INIS)

    Ji Jun; Gore, Jay P.; Sivathanu, Yudaya R.; Lim, Jongmook

    2004-01-01

    A fast infrared array spectrometer (FIAS) with a thermoelectrically cooled 160-element PbSe detector was demonstrated using measurements of instantaneous infrared radiation intensities simultaneously over the 1.8-4.9 μm wavelength range at a sampling rate of 390 Hz. A three-point second-degree Lagrange interpolation polynomial was constructed to calibrate the FIAS because of the nonlinear response of the infrared array detector to the incident radiation beam. This calibration method gave excellent measurements of blackbody radiation spectra except for a narrow band at wavelength of 4.3 μm due to absorption by room carbon dioxide, which is one of the two major gas radiation peaks (2.7 and 4.3 μm) from the lean premixed hydrocarbon/air combustion products in the midinfrared spectrum. Therefore, the absorption coefficient of room carbon dioxide was conveniently measured on site with the blackbody reference source, and was used in the calibration of the FIAS and also in the calculations of the radiation spectra. Blackbody tests showed that this procedure was effective in correcting for the room carbon dioxide absorption in the radiation spectra measured by the FIAS. For an example of its application, the calibrated FIAS was used to measure spectral radiation intensities from three lean premixed laminar flames and a premixed turbulent jet flame for which reference data with a grating spectrometer were available for comparison. The agreement between the FIAS measurements and the reference data was excellent

  14. Wide-aperture magnetic spectrometer with face position of MWPC

    International Nuclear Information System (INIS)

    Avakyan, R.O.; Avetisyan, A.Eh.; Ajvazyan, R.B.; Asaturyan, R.A.; Dallakyan, K.R.; Kizogyan, O.S.; Matevosyan, Eh.M.; Sukiasyan, Yu.Z.; Taroyan, S.P.

    1988-01-01

    A pair magnetic spectrometer with automated wire chambers for studying electron and positron interactions with monocrystals at the Erevan synchrotron is described. As a working gas the argon-methane mixture with methylal vapor addition is used. Results of modelling and experiments with spectrometer are presented. 2 refs.; 6 figs

  15. The full automation of a Philips 1220 x-ray spectrometer

    International Nuclear Information System (INIS)

    Austen, C.E.

    1976-01-01

    A Philips 1220 X-ray spectrometer (semi-automatic) was fully automated by the addition of a custom-built automatic sample-loader constructed at the National Institute for Metallurgy and a Texas 980 A mini-computer. The mini-computer was interfaced to the existing control circuits of the X-ray spectrometer through a custom-built logic-circuit unit that controls the automatic sample-loader and X-ray spectrometer on instructions received from the mini-computer. The controlling software is written in BASIC

  16. Ion transmission in a linear radiofrequency spectrometer

    International Nuclear Information System (INIS)

    Gomet, J.-C.

    1975-01-01

    A linear radiofrequency spectrometer is used for the purpose of experimental determination of the absolute ionization cross sections of various ions obtained by electron impact on polyatomic molecules. The transmission of the apparatus is studied: it does not only depend on the mass resolution of the spectrometer, but also on the nature of ions. It is affected by charge transfers, especially for the parent ions. An empiric way of correction of the apparatus function is given which allows the use at 10 -6 Torr [fr

  17. ''VECTON-1'' two-arm spectrometer for rho--meson photoproduction study

    International Nuclear Information System (INIS)

    Anokhin, M.V.; Kanetsyan, A.R.; Kukarev, V.M.

    1977-01-01

    A two-arm spectrometer for registering p - mesons according to a charged pion and one of the neutral pion disintegration photons has been designed. The spectrometer arm which registers charged pion comprises a deflecting magnet, dual wide-gap spark chambers and dual scintillation counters. The spectrometer arm for registering the disintegration photon comprises a scintillation counter, a dual wide-gap spark chamber and a shower detector. The principal characteristics of the spectrometer components are listed. The functional diagram of the useful events selection unit is discussed. It is shown that the experimental results obtained with the aid of the ''VEKTON-1'' set-up are in good agreement with the earlier results: P - meson rest energy is 731+-30 MeV, the resonant range width is 195+-58 MeV

  18. Magnetic field calculation of the Na-4 muon spectrometer

    International Nuclear Information System (INIS)

    Cvach, J.; Il'yushchenko, V.I.; Savin, I.A.; Vorozhtsov, S.B.

    1980-01-01

    A NA-4 muon spectrometer is described. Preliminary results of calculating a magnetic field in a toroidal magnetic detector are given. The spectrometer includes 10 similar supermodules each of which consists of 32 iron discs with 275 cm outer diameter magnetized up to saturation. Each module is an independent detector. The POISSON program is used for calculating magnetic field distribution in a toroidal spectrometer magnet. The results obtained show that a magnetic field of iron is a toroidal one and drops approximately according to the logarithmic law from 21.1 kGs on an inner magnet rig to 17.7 kGs on an outer. Magnet support gives approximately 2 % error

  19. Atrophic Gastritis and the Risk of Incident Colorectal Cancer

    Science.gov (United States)

    Laiyemo, Adeyinka O.; Kamangar, Farin; Marcus, Pamela M.; Taylor, Philip R.; Virtamo, Jarmo; Albanes, Demetrius; Stolzenberg-Solomon, Rachael Z.

    2012-01-01

    Objective Previous studies evaluating whether risk factors for gastric cancer are also associated with colorectal cancer (CRC) have shown inconsistent results. We prospectively examined the association of atrophic gastritis, a pre-malignant condition for gastric cancer and long-term sequelae common to many exposure factors, and the risk of incident CRC. Methods A total of 20,928 Finnish male smokers, aged 50–69, who were participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) had serum pepsinogen I (SPGI) levels measured. Participants with low SPGI levels (gastritis was histologically confirmed in 1,006 (95.0%) participants. We used Cox proportional hazards regression to evaluate the risk of incident CRC. Results During a mean follow-up of 11.3 years (236,258 person-years), 425 incident CRC were diagnosed. The incidence rates were 1.82, 1.48, and 1.82 per 1,000 person-years of follow-up for participants with normal SPGI (≥25 µg/l), low SPGI, and histologically-confirmed atrophic gastritis, respectively. Compared to subjects with normal SPGI, there was no increased risk of CRC among subjects with low SPGI (Adjusted Hazard Ratio (HR) = 0.71; 95%CI: 0.47–1.05) and among those with histologically-confirmed atrophic gastritis (Adjusted HR = 0.86; 95%CI: 0.55–1.34). Conclusions Atrophic gastritis is not associated with an increased risk of colorectal cancer among male smokers. PMID:19838812

  20. Time-of-flight small-angle scattering spectrometers on pulsed neutron sources

    International Nuclear Information System (INIS)

    Ostanevich, Yu.M.

    1987-01-01

    The operation principles, constructions, advantages and shortcomings of known time-of-flight small angle neutron scattering (TOF SANS) spectrometers built up with pulsed neutron sources are reviewed. The most important characteristics of TOF SANS apparatuses are rather a high luminosity and the possibility for the measurement in an extremely wide range of scattering vector at a single exposure. This is achieved by simultaneous employment of white beam, TOF technique for wave length-scan and the commonly known angle-scan. However, the electronic equipment, data-matching programs, and the measurement procedure, necessary for accurate normalization of experimental data and their transformation into absolute cross-section scale, they all become more complex, as compared with those for SANS apparatuses operating on steady-state neutron sources, where only angle-scan is used

  1. Au-Spec: An Integrated Spectrometer for Terahertz Space Spectroscopy

    Science.gov (United States)

    Moseley, Samuel

    Under APRA funding, we have developed a fully integrated R~64 submillimeter spectrometer. Using only single crystal Si and superconductors, our fabrication process is designed with the goal of minimizing loss in the spectrometer. High performance designs have been developed for all the required elements of the spectrometer. For example the slot antenna, power divider microstip delay lines, absorbers, and M icrowave Kinetic Inductance detectors (MKIDs) have been designed and buit, and the performance of a system operating at R~ 64 has been demonstrated. We l propose to develop and test a spectrometer with R~300. This device can be produced to sufficient accuracy with known fabrication tolerances. After the successful demonstration of the R~300 instrument, the devices will be ready for application in balloon or airborne applications.We will measure loss in the transmission lines to establish the limits of resolving power in such a materials system and will develop a phase adjuster to allow a diffraction limited delay network at the full resolution allowed by loss in the materials. We will demonstrate the performance of this system with R~1000 by the end of the proposed program. Arrays of such integrated spectrometers are ideal building blocks for a high redshift survey instrument, and its compact size may allow significant science to be done on Explorer Class Missions.

  2. Survey of incidents in West German nuclear power plants in the last quarter of the year 1988

    International Nuclear Information System (INIS)

    1989-01-01

    There were 79 incidents reported. Six incidents belong to reporting category E (immediate notification), the remaining 73 incidents belong to reporting category N (normal notification). The survey covers all incidents reported to GRS until the 15th of February 1989 and also includes incidents that happened before the last quarter of 1988 but were recorded later. There was no release of radioactivity involved in the incidents, and there are no effects on man or the environment reported. (orig./HP) [de

  3. Design of a π0 spectrometer at LAMPF

    International Nuclear Information System (INIS)

    Heffner, R.

    1976-01-01

    A discussion is given of the salient features for the design of a π 0 spectrometer being constructed at LAMPF. The basic concepts of π 0 detection are explained, and the expected performance and mechanical design of the instrument are discussed. A list of intended experiments to be undertaken is given. The spectrometer is intended to be used for pion-charge-exchange and production reactions with nuclear targets

  4. Heat of vaporization spectrometer

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1978-01-01

    Multilayer desorption measurements of various substances adsorbed on a stainless steel substrate are found to exhibit desorption profiles consistent with a zeroth order desorption model. The singleness of the desorption transients together with their narrow peak widths makes the technique ideally suited for a heat of vaporization spectrometer for either substance analysis or identification

  5. Magnetic field calculations for the technical proposal of the TESLA spectrometer magnet

    International Nuclear Information System (INIS)

    Morozov, N.A.; Schreiber, H.J.

    2003-01-01

    The TESLA electron-positron linear collider is under consideration at DESY (Hamburg). The realization of the physical program at this collider requires the knowledge of the beam energy of both beams (e + and e - ) with a precision of ΔE/E ≤ 10 -4 . The magnetic spectrometer was proposed as an energy measuring device. The report describes calculations for the preliminary conceptual design of this type of the spectrometer. The 2D calculations of the magnetic field for the spectrometer magnet have been performed by POISSON SUPERFISH computer code. The basic technical parameters of the magnet have been determined. These data will serve as a basis for the technical design of the spectrometer magnet and discuss its integration in the spectrometer

  6. Incidence of cervical dysplasia and cervical cancer in women living with HIV in Denmark

    DEFF Research Database (Denmark)

    Thorsteinsson, K; Ladelund, Steen; Jensen-Fangel, S

    2016-01-01

    , which contains nationwide records of all pathology specimens. The cumulative incidence and hazard ratios (HRs) for time from inclusion to first cervical intraepithelial neoplasia (CIN)/ICC and time from first normal cervical cytology result to first CIN/ICC were estimated. Sensitivity analyses were......OBJECTIVES: Women living with HIV (WLWH) are reportedly at increased risk of invasive cervical cancer (ICC). A recent publication found that WLWH in Denmark attend the national ICC screening programme less often than women in the general population. We aimed to estimate the incidence of cervical...... in both groups were adherent to the national ICC screening programme and had a normal baseline cytology, incidences of CIN and ICC were comparable. CONCLUSIONS: Overall, WLWH developed more cervical disease than controls. Yet, in WLWH and controls adherent to the national ICC screening programme...

  7. Large acceptance spectrometers for π0 mesons

    International Nuclear Information System (INIS)

    Awes, T.C.; Ferguson, R.L.; Obenshain, F.E.

    1984-01-01

    A spectrometer composed of lead-oxide loaded glass blocks has been constructed for detection of neutral pi mesons emitted in low energy heavy ion reactions. The spectrometer detects the Cerenkov radiation emitted when the high energy photons (Eγ approx. 70 MeV) resulting from π 0 decay create electron-position pairs in the glass, initiating electromagnetic showers. A geometric acceptance of better than 5% of 4π is possible; the π 0 detection efficiency varies between this value at T/sub π/ = 0 MeV and 1% for T/sub π/ approx. 100 MeV

  8. Large acceptance magnetic spectrometers for polarized deep inelastic electron scattering

    International Nuclear Information System (INIS)

    Petratos, G.G.; Eisele, R.L.; Gearhart, R.A.; Hughes, E.W.; Young, C.C.

    1991-10-01

    The design of two magnetic spectrometers for the measurement of the spin-dependent structure function g 1 n of the neutron and a test of the Bjorken sum rule is described. The measurement will consist of scattering 23 GeV polarized electrons off a polarized 3 He target and detecting scattered electrons of 7 to 18 GeV at 4.5 degree and 7 degree. Each spectrometer is based on two large aperture dipole magnets bending in opposite directions. This ''reverse'' deflection design doubles the solid angle as compared to the conventional design of same direction bends used in previous experiments. Proper choice of the deflection angles and the distance between the two dipoles in each spectrometer allows background photons from radiative processes to reach the detectors only after at least two bounces off the spectrometer vacuum walls, resulting in an expected tolerable background. Each spectrometer is equipped with a pair of Cerenkov detectors, a pair of scintillation hodoscopes and a lead-glass shower calorimeter providing electron and pion identification with angular and momentum resolutions sufficient for the experimental measurement. 7 refs., 8 figs., 1 tab

  9. The polarized neutron spectrometer REMUR at the pulsed reactor IBR-2

    International Nuclear Information System (INIS)

    Aksenov, V.L.; Zhernenkov, K.N.; Kozhevnikov, S.V.; Nikitenko, Yu.V.; Petrenko, A.V.; Lauter, H.J.; Lauter-Pasyuk, V.

    2004-01-01

    At the Laboratory of Neutron Physics (JINR, Dubna) the new polarized neutron spectrometer REMUR has been constructed and commissioned. The spectrometer REMUR is dedicated to investigations of multilayers and surfaces by polarized neutron reflection and of the inhomogeneous state of solids by diffuse small-angle polarized neutron scattering. The spectrometer operates in the neutron wavelength interval 1-10 Angstroem. In the reflectometry mode it allows one to complete polarization analysis and neutron position-sensitive detection within the solid angle of scattering 2.2·10 -4 rad. The spectrometer ensures good statistics of the reflectometric data in the scattering wave vector interval 3·10 -3 - 5·10 -1 Angstroem -1 . In the small-angle scattering mode the spectrometer allows the investigation of neutron scattering processes without spin-flip over the detector's neutron registration solid angle interval from 4·10 -3 to 10 -1 rad and the scattering wave vector interval from 0.006-0.15 to 0.03-0.7 Angstroem -1 , respectively

  10. Feasibility studies for the Forward Spectrometer

    International Nuclear Information System (INIS)

    Biernat, Jacek

    2015-01-01

    The Forward Spectrometer designed for the P-barANDA detector will consist of many different detector systems allowing for precise track reconstruction and particle identification. Feasibility studies for Forward Spectrometer done by means of specific reactions will be presented. In the first part of the paper, results of simulations focussing on rate estimates of the tracking stations based on straw tubes will be presented. Next, the importance of the Forward Tracker will be demonstrated through the reconstruction of the ψ(4040) → DD-bar decay. Finally, results from the analysis of the experimental data collected with a straw tube prototype designed and constructed at the Research Center in Juelich will be discussed. (paper)

  11. The transition-edge EBIT microcalorimeter spectrometer

    Science.gov (United States)

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

    2014-07-01

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

  12. Current instrument status of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    Science.gov (United States)

    Eastwood, Michael L.; Sarture, Charles M.; Chrien, Thomas G.; Green, Robert O.; Porter, Wallace M.

    1991-01-01

    An upgraded version of AVIRIS, an airborne imaging spectrometer based on a whiskbroom-type scanner coupled via optical fibers to four dispersive spectrometers, that has been in operation since 1987 is described. Emphasis is placed on specific AVIRIS subsystems including foreoptics, fiber optics, and an in-flight reference source; spectrometers and detector dewars; a scan drive mechanism; a signal chain; digital electronics; a tape recorder; calibration systems; and ground support requirements.

  13. A multi-analyzer crystal spectrometer (MAX) for pulsed neutron sources

    International Nuclear Information System (INIS)

    Tajima, K.; Ishikawa, Y.; Kanai, K.; Windsor, C.G.; Tomiyoshi, S.

    1982-03-01

    The paper describes the principle and initial performance of a multi-analyzer crystal spectrometer (MAX) recently installed at the KENS spallation neutron source at Tsukuba. The spectrometer is able to make time of flight scans along a desired direction in reciprocal space, covering a wide range of the energy transfers corresponding to the fifteen analyzer crystals. The constant Q or constant E modes of operation can be performed. The spectrometer is particularly suited for studying collective excitations such as phonons and magnons to high energy transfers using single crystal samples. (author)

  14. Secondary electron emission of sapphire tungsten molybdenum and titanium for Maxwellian incident electrons

    International Nuclear Information System (INIS)

    Saussez-Hublet, M.-C.; Harbour, P.J.

    1980-06-01

    The second electron emission coefficient of various materials, namely titanium, molybdenum, tungsten and sapphire, has been calculated for a Maxwellian energy distribution from data for a normally incident monoenergetic beam of primary electrons. The most significant difference from the monoenergetic case occurs at low energies. In addition the influence of the incident angle of the electrons is discussed. (author)

  15. STRATEG - an incident training system for thermohydraulic effects and principles

    International Nuclear Information System (INIS)

    Rehn, H.; Majohr, N.

    1993-01-01

    STRATEG is a 1:10 scale glass model of a PWR (Biblis B reactor coolant circuit) built by RWE in 1986 on the site of the Biblis plant as a training model. The model can be used for training of normal operation and incident situations since all important operating and incident sequences of a PWR can be simulated. Thermodynamic phenomena can also be demonstrated occurring under various operating situations and in particular associated with malfunctions. (Z.S.) 1 tab., 3 figs., 1 ref

  16. Research of high power and stable laser in portable Raman spectrometer based on SHINERS technology

    Science.gov (United States)

    Cui, Yongsheng; Yin, Yu; Wu, Yulin; Ni, Xuxiang; Zhang, Xiuda; Yan, Huimin

    2013-08-01

    The intensity of Raman light is very weak, which is only from 10-12 to 10-6 of the incident light. In order to obtain the required sensitivity, the traditional Raman spectrometer tends to be heavy weight and large volume, so it is often used as indoor test device. Based on the Shell-Isolated Nanoparticle-Enhanced Raman Spectroscopy (SHINERS) method, Raman optical spectrum signal can be enhanced significantly and the portable Raman spectrometer combined with SHINERS method will be widely used in various fields. The laser source must be stable enough and able to output monochromatic narrow band laser with stable power in the portable Raman spectrometer based on the SHINERS method. When the laser is working, the change of temperature can induce wavelength drift, thus the power stability of excitation light will be affected, so we need to strictly control the working temperature of the laser, In order to ensure the stability of laser power and output current, this paper adopts the WLD3343 laser constant current driver chip of Wavelength Electronics company and MCU P89LPC935 to drive LML - 785.0 BF - XX laser diode(LD). Using this scheme, the Raman spectrometer can be small in size and the drive current can be constant. At the same time, we can achieve functions such as slow start, over-current protection, over-voltage protection, etc. Continuous adjustable output can be realized under control, and the requirement of high power output can be satisfied. Max1968 chip is adopted to realize the accurate control of the laser's temperature. In this way, it can meet the demand of miniaturization. In term of temperature control, integral truncation effect of traditional PID algorithm is big, which is easy to cause static difference. Each output of incremental PID algorithm has nothing to do with the current position, and we can control the output coefficients to avoid full dose output and immoderate adjustment, then the speed of balance will be improved observably. Variable

  17. Cold-neutron multi-chopper spectrometer for MLF, J-PARC

    International Nuclear Information System (INIS)

    Nakajima, Kenji; Kajimoto, Ryoich; Nakamura, Mistutaka; Arai, Masatoshi; Sato, Taku J.; Osakabe, Toyotaka; Matsuda, Masaaki; Metoki, Naoto; Kakurai, Kazuhisa; Itoh, Shinichi

    2005-01-01

    We are planning to construct a cold-neutron multi-chopper spectrometer for a new spallation neutron source at Materials and Life Science Facility (MLF) at J-PARC, which is dedicated to investigation of low energy excitations and quasi-elastic excitations in the field of solid state physics, chemistry, materials science, soft matter science and biomaterial science. The planned spectrometer will be installed at a H 2 -coupled moderator and will be equipped with a pulse-shaping disk-chopper in addition to a monochromating disk-chopper, and realizes both high-energy resolution (ΔE/E i ≥1%) and high-intensity (one order of magnitude higher than the present state-of-the-art chopper spectrometers)

  18. Mass-spectrometer MASHA - testing results on heavy ion beam

    International Nuclear Information System (INIS)

    Rodin, A.M.; Belozerov, A.V.; Vanin, D.V.; Dmitriev, S.N.; Itkis, M.G.; Kliman, J.; Krupa, L.; Lebedev, A.N.; Oganesyan, Yu.Ts.; Salamatin, V.S.; Sivachek, I.; Chernysheva, E.V.; Yukhimchuk, S.A.

    2011-01-01

    Description of mass-spectrometer MASHA, developed for the mass identification of superheavy elements, is given. The efficiency and operation speed in the off-line mode were measured with four calibrated leakages of noble gases. The total efficiency and operation speed of mass-spectrometer with hot catcher and ECR ion source were determined using the 40 Ar beam. The test experiment was carried out by measuring the alpha decay of Hg and Rn isotopes, produced in fusion reactions 40 Ar+ nat Sm→ nat-xn Hg+xn and 40 Ar+ 166 Er→ 206-xn Rn+xn, in the focal plane of mass-spectrometer. The operation speed of the given technique and relative yields of isotopes in the test reactions were determined

  19. Deadtime measurement for the new gamma spectrometer system

    International Nuclear Information System (INIS)

    Chen Fangqiang; Ge Liangquan; Luo Yaoyao; Ni Weichong; Zeng Guoqiang; An Zhengwei; Mi Yaohui

    2010-01-01

    It introduces the reasons,the representation,the related theory and the measuring steps of the traditional dual-source method. And we also introduce a new kind of airborne Gamma-Ray spectrometer. In single connection circumstances, we confirmed the validity of the dual-source net counts method by comparing the results of four modes. The deadtime of the new kind of airborne Gamma-Ray spectrometer is measured, and the conclusion and some advice are given. (authors)

  20. Combined Raman spectrometer/laser-induced breakdown spectrometer for the next ESA mission to Mars

    Science.gov (United States)

    Bazalgette Courrèges-Lacoste, Grégory; Ahlers, Berit; Pérez, Fernando Rull

    2007-12-01

    Among the different instruments that have been pre-selected to be on-board the Pasteur payload on ExoMars is the Raman/ laser induced breakdown spectroscopy (LIBS) instrument. Raman spectroscopy and LIBS will be integrated into a single instrument sharing many hardware commonalities. An international team under the lead of TNO has been gathered to produce a design concept for a combined Raman spectrometer/LIBS elegant bread-board (EBB). The instrument is based on a specially designed, extremely compact, spectrometer with high resolution over a large wavelength range, suitable for both Raman spectroscopy and LIBS measurements. Low mass, size and power consumption are the main drivers of the instrument's design concept. In this paper, science objectives for the combined instrument are detailed. Background information on Raman spectroscopy and LIBS are presented, focussing on the synergy of these two techniques. In the last section, the instrument concept resulting from the assessment of the feasibility of the combined Raman/LIBS EBB is presented.

  1. Split-field FDTD method for oblique incidence study of periodic dispersive metallic structures.

    Science.gov (United States)

    Baida, F I; Belkhir, A

    2009-08-15

    The study of periodic structures illuminated by a normally incident plane wave is a simple task that can be numerically simulated by the finite-difference time-domain (FDTD) method. On the contrary, for off-normal incidence, a widely modified algorithm must be developed in order to bypass the frequency dependence appearing in the periodic boundary conditions. After recently implementing this FDTD algorithm for pure dielectric materials, we here extend it to the study of metallic structures where dispersion can be described by analytical models. The accuracy of our code is demonstrated through comparisons with already-published results in the case of 1D and 3D structures.

  2. Automation of a thermal ionisation mass spectrometer

    International Nuclear Information System (INIS)

    Pamula, A.; Leuca, M.; Albert, S.; Benta, Adriana

    2001-01-01

    A thermal ionization mass spectrometer was upgraded in order to be monitored by a PC. A PC-LMP-16 National Instruments data acquisition board was used for the ion current channel and the Hall signal channel. A dedicated interface was built to allow commands from the computer to the current supply of the analyzing magnet and to the high voltage unit of the mass spectrometer. A software application was worked out to perform the adjustment of the spectrometer, magnetic scanning and mass spectra acquisition, data processing and isotope ratio determination. The apparatus is used for isotope ratio 235 U/ 238 U determination near the natural abundance. A peak jumping technique is applied to choose between the 235 U and 238 U signal, by switching the high voltage applied to the ion source between two preset values. This avoids the delay between the acquisition of the peaks of interest, a delay that would appear in the case of a 'pure' magnetic scanning. Corrections are applied for the mass discrimination effects and a statistical treatment of the data is achieved. (authors)

  3. Multichannel analyzer for the neutron time-of-flight spectrometer

    International Nuclear Information System (INIS)

    Vojter, A.P.; Slyisenko, V.Yi.; Doronyin, M.Yi.; Maznij, Yi.O.; Vasil'kevich, O.A.; Golyik, V.V.; Koval'ov, O.M.; Kopachov, V.Yi.; Savchuk, V.G.

    2010-01-01

    New multichannel time-of-flight spectrometer for the measurement of the energy and angular distributions of neutrons from the WWWR-M reactor is considered. This spectrometer has been developed for the replacement of the previous one to increase the number of channels and measurement precision, reduce the time of channel tuning and provide the automatic monitoring during the experiment.

  4. Absolutely nondestructive discrimination of Huoshan Dendrobium nobile species with miniature near-infrared (NIR) spectrometer engine.

    Science.gov (United States)

    Hu, Tian; Yang, Hai-Long; Tang, Qing; Zhang, Hui; Nie, Lei; Li, Lian; Wang, Jin-Feng; Liu, Dong-Ming; Jiang, Wei; Wang, Fei; Zang, Heng-Chang

    2014-10-01

    As one very precious traditional Chinese medicine (TCM), Huoshan Dendrobium has not only high price, but also significant pharmaceutical efficacy. However, different species of Huoshan Dendrobium exhibit considerable difference in pharmaceutical efficacy, so rapid and absolutely non-destructive discrimination of Huoshan Dendrobium nobile according to different species is crucial to quality control and pharmaceutical effect. In this study, as one type of miniature near-infrared (NIR) spectrometer, MicroNIR 1700 was used for absolutely nondestructive determination of NIR spectra of 90 batches of Dendrobium from five species of differ- ent commodity grades. The samples were intact and not smashed. Soft independent modeling of class analogy (SIMCA) pattern recognition based on principal component analysis (PCA) was used to classify and recognize different species of Dendrobium samples. The results indicated that the SIMCA qualitative models established with pretreatment method of standard normal variate transformation (SNV) in the spectra range selected by Qs method had 100% recognition rates and 100% rejection rates. This study demonstrated that a rapid and absolutely non-destructive analytical technique based on MicroNIR 1700 spectrometer was developed for successful discrimination of five different species of Huoshan Dendrobium with acceptable accuracy.

  5. Major Incident Hospital: Development of a Permanent Facility for Management of Incident Casualties.

    Science.gov (United States)

    Marres, Geertruid; Bemelman, Michael; van der Eijk, John; Leenen, Luke

    2009-06-01

    Preparation is essential to cope with the challenge of providing optimal care when there is a sudden, unexpected surge of casualties due to a disaster or major incident. By definition, the requirements of such cases exceed the standard care facilities of hospitals in qualitative or quantitative respects and interfere with the care of regular patients. To meet the growing demands to be prepared for disasters, a permanent facility to provide structured, prepared relief in such situations was developed. A permanent but reserved Major Incident Hospital (MIH) has been developed through cooperation between a large academic medical institution, a trauma center, a military hospital, and the National Poison Information Centre (NVIC). The infrastructure, organization, support systems, training and systematic working methods of the MIH are designed to create order in a chaotic, unexpected situation and to optimize care and logistics in any possible scenario. Focus points are: patient flow and triage, registration, communication, evaluation and training. Research and the literature are used to identify characteristic pitfalls due to the chaos associated with and the unexpected nature of disasters, and to adapt our organization. At the MIH, the exceptional has become the core business, and preparation for disaster and large-scale emergency care is a daily occupation. An Emergency Response Protocol enables admittance to the normally dormant hospital of up to 100 (in exceptional cases even 300) patients after a start-up time of only 15 min. The Patient Barcode Registration System (PBR) with EAN codes guarantees quick and adequate registration of patient data in order to facilitate good medical coordination and follow-up during a major incident. The fact that the hospital is strictly reserved for this type of care guarantees availability and minimizes impact on normal care. When it is not being used during a major incident, there is time to address training and research

  6. Detailed spectroscopy of the normally deformed states in 132Ce

    International Nuclear Information System (INIS)

    Paul, E.S.; Gizon, A.; Gizon, J.; Santos, D.; Nyako, B.M.; O'Brien, N.J.; Parry, C.M.; Wadsworth, R.

    1997-01-01

    High-spin states have been studied in 132 Ce produced in the 100 Mo( 36 S,4nγ) reaction using the EUROGAM II spectrometer. The structure of the normally deformed states (β 2 ∝0.2) has been investigated. Eight ΔI=2 bands and three ΔI=1 bands have been identified and the level scheme extended up to spin and parity (40 + ) at an excitation energy 19.79 MeV. The results are interpreted with the aid of Woods-Saxon cranking calculations, which suggest a variety of triaxial (γ) shapes in this nucleus stabilised by specific active quasiparticle orbitals. (orig.)

  7. SIR-2 Data Normalization and Integration with M3 Data

    Science.gov (United States)

    Grumpe, A.; Felder, M. P.; Wöhler, C.; Mall, U.

    2013-09-01

    The point spectrometer SIR-2 on Chandrayaan-1 provided radiance spectra integrated over circular footprints of 200 m diameter in the wavelength range 934-2410.8 nm in 256 channels [1]. To analyze SIR-2 reflectance spectra in their spatial context, a coregistration to Chandrayaan-1 M³ hyperspectral images [2] as well as a correction for topography and thermal emission are inevitable. The thermal and topographic correction procedure is based on the surface temperature and a digital elevation model (DEM) inferred from M³ data. The corrected reflectance spectra are then normalized to a standard illumination and viewing geometry.

  8. Micro-Spec: A High Performance Compact Spectrometer for Submillimeter Astronomy

    Science.gov (United States)

    Hsieh, Wen-Ting; Moseley, Harvey; Stevenson, Thomas; Brown, Ari; Patel, Amil; U-Yen, Kongpop; Ehsan, Negar; Caltado, Giuseppe; Wollock, Edward

    2012-01-01

    We describe the micro-Spec, an extremely compact high performance spectrometer for the submillimeter and millimeter spectral ranges. We have designed a fully integrated submillimeter spectrometer based on superconducting microstrip technology and fabricated its critical elements. Using low loss transmission lines, we can produce a fully integrated high resolution submillimeter spectrometer on a single four inch Si wafer. A resolution of 500 can readily be achieved with standard fabrication tolerance, higher with phase trimming. All functions of the spectrometer are integrated - light is coupled to the micro strip circuit with a planar antenna, the spectra discrimination is achieved using a synthetic grating, orders are separated using a built-in planar filter, and the light is detected using photon counting Microwave Kinetic Inductance Detectors (MKID). We will discus the design principle of the instrument, describe its technical advantages, and report the progress on the development of the instrument.

  9. Mu-Spec: A High Performance Compact Spectrometer for Submillimeter Astronomy

    Science.gov (United States)

    Hsieh, Wen-Ting; Moseley, Harvey; Stevenson, Thomas; Brown, Ari; Patel, Amil; U-yen, Kongpop; Ehsan, Negar; Cataldo, Giuseppe; Wollack, Ed

    2012-01-01

    We describe the Mu-Spec, an extremely compact high performance spectrometer for the submillimeter and millimeter spectral ranges. We have designed a fully integrated submillimeter spectrometer based on superconducting microstrip technology and fabricated its critical elements. Using low loss transmission lines, we can produce a fully integrated high resolution submillimeter spectrometer on a single four inch Si wafer. A resolution of 500 can readily be achieved with standard fabrication tolerance, higher with phase trimming. All functions of the spectrometer are integrated - light is coupled to the microstrip circuit with a planar antenna, the spectra discrimination is achieved using a synthetic grating, orders are separated using a built-in planar filter, and the light is detected using photon counting Microwave Kinetic Inductance Detectors (MKID). We will discus the design principle of the instrument, describe its technical advantages, and report the progress on the development of the instrument.

  10. Airborne gamma ray spectrometer surveying

    International Nuclear Information System (INIS)

    1991-01-01

    The International Atomic Energy Agency (IAEA) in its role as collector and disseminator of information on nuclear techniques has long had an interest in gamma ray spectrometer methods and has published a number of Technical Reports on various aspects of the subject. At an Advisory Group Meeting held in Vienna in November 1986 to review appropriate activities the IAEA could take following the Chernobyl accident, it was recommended that preparation begin on a new Technical Report on airborne gamma ray spectrometer surveying, taking into account the use of the technique for environmental monitoring as well as for nuclear emergency response requirements. Shortly thereafter the IAEA became the lead organization in the Radioelement Geochemical Mapping section of the International Geological Correlation Programme/United Nations Educational, Scientific and Cultural Organization (UNESCO) Project on International Geochemical Mapping. These two factors led to the preparation of the present Technical Report. 18 figs, 4 tabs

  11. QQDDQ magnet spectrometer 'BIG KARL'

    Energy Technology Data Exchange (ETDEWEB)

    Martin, S A; Hardt, A; Meissburger, J; Berg, G P.A.; Hacker, U; Huerlimann, W; Roemer, J G.M.; Sagefka, T; Retz, A; Schult, O W.B.

    1983-09-01

    A magnet spectrometer consisting of two quadrupoles, two dipole magnets and another larger quadrupole in front of the detector was designed and installed at the nuclear research institute of the KFA Juelich. It has been used for charged-particle spectroscopy at the isochronous cyclotron since early 1979. Special features of the spectrometer are variable and high dispersion, coils for higher order field corrections in the dipole magnets and a focal plane perpendicular to the optical axis. A large mass-energy product of mE/q/sup 2/ < 540 u x MeV, an angular acceptance of d..cap omega..<12.5 msr, a high resolving power of p/..delta..p up to 3 x 10/sup 4/ and the possibility of kinematical corrections up to K=0.8 make the instrument a very versatile tool for many experiments in the fields of nuclear and atomic physics. 51 references.

  12. MEMS tunable grating micro-spectrometer

    Science.gov (United States)

    Tormen, Maurizio; Lockhart, R.; Niedermann, P.; Overstolz, T.; Hoogerwerf, A.; Mayor, J.-M.; Pierer, J.; Bosshard, C.; Ischer, R.; Voirin, G.; Stanley, R. P.

    2017-11-01

    The interest in MEMS based Micro-Spectrometers is increasing due to their potential in terms of flexibility as well as cost, low mass, small volume and power savings. This interest, especially in the Near-Infrared and Mid- Infrared, ranges from planetary exploration missions to astronomy, e.g. the search for extra solar planets, as well as to many other terrestrial fields of application such as, industrial quality and surface control, chemical analysis of soil and water, detection of chemical pollutants, exhausted gas analysis, food quality control, process control in pharmaceuticals, to name a few. A compact MEMS-based Spectrometer for Near- Infrared and Mid-InfraRed operation have been conceived, designed and demonstrated. The design based on tunable MEMS blazed grating, developed in the past at CSEM [1], achieves state of the art results in terms of spectral resolution, operational wavelength range, light throughput, overall dimensions, and power consumption.

  13. Rotating double arm spectrometer to study hard scattering interactions at Serpukhov accelerator

    International Nuclear Information System (INIS)

    Abramov, V.V.; Baldin, B.Yu.; Buzulutskov, A.F.

    1991-01-01

    The double arm magnetic spectrometer designed to study high P T particle production with intense proton and pion beams is described. Particle trajectories are measured by the drift and proportional chambers. Particles are identified by Cherenkov ring spectrometer and muon identifier. The spectrometer can be rotated around the target up to 160 mrad. 2 tabs.; 13 figs

  14. The calibration of spectrometers for Auger electron and X-ray photoelectron spectrometers part II - the determination of the electron spectrometer transmission function and the detector sensitivity energy dependencies

    International Nuclear Information System (INIS)

    Smith, G.C.; Seah, M.P.

    1991-01-01

    For the use of published general or theoretical sensitivity factors in quantitative AES and XPS the energy dependence of both the spectrometer transmission function and the detector sensitivity must be known. Here we develop simple procedures which allow these dependencies to be determined experimentally. Detailed measurements for a modified VG Scientific ESCALAB II, the metrology spectrometer, operated in both the constant ΔE/E and constant ΔE modes, are presented and compared with theoretical estimates. It is shown that an exceptionally detailed electron-optical calculation, involving proprietary information, would be required to match the accuracy of the experimental procedures developed. Removal of the spectrometer transmission function and the detector sensitivity terms allows the measured spectrum to be converted to the true electron emission spectrum irrespective of the mode of operation. This provides the first step to the provision of reference samples to calibrate the transmission functions and detector sensitivities of all instruments so that they, in turn, may produce true electron emission spectra. This is vital if (i) all instruments are to give consistent results, (ii) theoretical terms are to be used in quantifying either AES or XPS and (iii) reference data banks are to be established for AES or XPS

  15. Determination of Benzene, Toluene, and Xylene by means of an ion mobility spectrometer device using photoionization

    Science.gov (United States)

    Leonhardt, J. W.; Bensch, H.; Berger, D.; Nolting, M.; Baumbach, J. I.

    1995-01-01

    The continuous monitoring of changes on the quality of ambient air is a field of advantage of ion mobility spectrometry. Benzene, Toluene, and Xylene are substances of special interest because of their toxicity. We present an optimized drift tube for ion mobility spectrometers, which uses photo-ionization tubes to produce the ions to be analyzed. The actual version of this drift tube has a length of 45 mm, an electric field strength established within the drift tube of about 180 V/cm and a shutter-opening-time of 400 mus. With the hydrogen tube used for ionisation a mean flux of 10(exp 12) photons/sq cm s was established for the experiments described. We discuss the results of investigations on Benzene, Toluene, and Xylene in normal used gasoline SUPER. The detection limits obtained with the ion mobility spectrometer developed in co-operation are in the range of 10 ppbv in this case. Normally, charge transfer from Benzene ions to Toluene takes place. Nevertheless the simultaneous determination in mixtures is possible by a data evaluation procedure developed for this case. The interferences found between Xylene and others are rather weak. The ion mobility spectra of different concentrations of gasoline SUPER are attached as an example for the resolution and the detection limit of the instrument developed. Resolution and sensitivity of the system are well demonstrated. A hand-held portable device produced just now is to be tested for special environmental analytical problems in some industrial and scientific laboratories in Germany.

  16. Metrology and Alignment of Light Weight Grazing Incidence X-Ray Mirrors

    Science.gov (United States)

    Zhang, William; Content, David; Petre, Robert; Saha, Timo

    2000-01-01

    Metrology and alignment of light weight X-ray optics have been a challenge for two reasons: (1) that the intrinsic mirror quality and distortions caused by handling can not be easily separated, and (2) the diffraction limits of the visible light become a severe problem at the order of one arc-minute. Traditional methods of using a normal incident pencil or small parallel beam which monitors a tiny fraction of the mirror in question at a given time can not adequately monitor those distortions. We are developing a normal incidence setup that monitors a large fraction, if not the whole, of the mirror at any given time. It will allow us to align thin X-ray mirrors to-an accuracy of a few arc seconds or to a limit dominated by the mirror intrinsic quality.

  17. Arrangement of remote control of spectrometers on IBR-2M reactor

    International Nuclear Information System (INIS)

    Kirilov, A.S.; Murashkevich, S.M.; Okulov, R.Yu.; Petukhova, T.B.; )

    2009-01-01

    The principles of arranging and design features of the WebSonix system consisting of the central web-site and interface equipment with spectrometers are considered. The system allows one to reflect the actual statuses of all spectrometer components, view the measurements protocols, display the accumulative spectra, and control the course of the experiment on the spectrometers under control of the Sonix+ software package (Windows XP operational system). The system does not depend on the spectrometer characteristics and permits simple changes of their structure and easy adaptation to special features of spectrometric data representation. The system is based on PHP and Python scripts. The GNU/Linux Debian operational system and Apache 2 web server are installed on the web-site computer [ru

  18. Double-arm time-of-flight mass-spectrometer of nuclear fragments

    International Nuclear Information System (INIS)

    Ajvazian, G.M.; Astabatyan, R.A.

    1995-01-01

    A double-arm time-of-flight spectrometer of nuclear fragments for the investigation of heavy nuclei photofission in the intermediate energy range is described. The calibration results and working characteristics of the spectrometer, obtained using 252 Cf as a source of spontaneous fission, are presented. A mass resolution of σ m ∼2-3 a.m.u. was obtained within the registered fragments mass range of 80-160 a.m.u. The spectrometer was tested in the experiment on the investigation of 238 U nuclei fission by Bremsstahlung photons with Eγ max=1.75 GeV

  19. Pulsed coherent spectrometer of nuclear magnetic and nuclear quadrupole resonance

    International Nuclear Information System (INIS)

    Karnachev, A.S.; Solov'ev, E.E.

    1996-01-01

    The spectrometer intended for studies on solid bodies was created on the basis of the X1-48 device for investigation of amplitude-frequency characteristics with the frequency range of 5-100 MHz, the receiver sensitivity by the signal-noise ratio at the outlet of 12 dB not worse than 0.5 μV and the feed-up capacity up to 80 W. The X1-48 minimal remodeling made it possible to use it in the spectrometer system as a signal feed-up source and measurer of the amplitude-frequency characteristic of the spectrometer receiver tract. 12 refs., 11 figs

  20. The role of vacuum in the quality of TOF mass spectrometer

    International Nuclear Information System (INIS)

    Bhowmick, A.; Gadkari, S.C.; Yakhmi, J.V.; Sahni, V.C.

    2005-01-01

    The art in the designing of time-of-flight mass spectrometers has come across a long course of development. The present day state-of-the-art machines are essentially the outcome of knowledge from the advances in different other areas of technology. This article discusses exclusively the role of UHV to enhance the quality of the TOF mass spectrometers and its application to the recently developed high resolution TOF mass spectrometer at TP and PED-BARC. (author)

  1. Improved yield of high resolution mercuric iodide gamma-ray spectrometers

    International Nuclear Information System (INIS)

    Gerrish, V.; van den Berg, L.

    1990-01-01

    Mercuric iodide (HgI 2 ) exhibits properties which make it attractive for use as a solid state nuclear radiation detector. The wide bandgap (E g = 2.1 eV) and low dark current allow room temperature operation, while the high atomic number provides a large gamma-ray cross section. However, poor hole transport has been a major limitation in the routine fabrication of high-resolution spectrometers using this material. This paper presents the results of gamma-ray response and charge transport parameter measurements conducted during the past year at EG ampersand G/EM on 96 HgI 2 spectrometers. The gamma-ray response measurements reveal that detector quality is correlated with the starting material used in the crystal growth. In particular, an increased yield of high-resolution spectrometers was obtained from HgI 2 which was synthesized by precipitation from an aqueous solution, as opposed to using material from commercial vendors. Data are also presented which suggest that better spectrometer performance is tied to improved hole transport. Finally, some initial results on a study of detector uniformity reveal spatial variations which may explain why the correlation between hole transport parameters and spectrometer performance is sometimes violated. 6 refs., 3 figs

  2. A 4π dilepton spectrometer: PEPSI

    International Nuclear Information System (INIS)

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

    1993-01-01

    A novel positron-electron pair spectroscopy instrument (PEPSI) was designed to measure transitions in the energy region 10-40 MeV. It consists of Nd 2 Fe 14 B permanent magnets forming a compact 4π magnetic filter consisting of 12 positron and 20 electron mini-orange-like spectrometers. The response function of PEPSI has been measured with mono-energetic beams of electrons from 5 to 20 MeV. The PEPSI spectrometer was used for measuring the internal pair conversion coefficient (α π ) of the 15.1 MeV M1 transition from a J π =1 + state to the ground state in 12 C. Our experimental value of α π =(3.3±0.5)x10 -3 is in good agreement with theoretical estimates. (orig.)

  3. A 4 π dilepton spectrometer: PEPSI

    Science.gov (United States)

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

    1993-11-01

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

  4. Tests of a prototype resonance filter spectrometer at WNR

    International Nuclear Information System (INIS)

    Newport, R.J.; Seeger, P.A.; Williams, W.G.

    1984-11-01

    Data gained during a series of developmental experiments using the SNS test resonance filter spectrometer at the WNR pulsed neutron facility, Los Alamos, are presented and discussed. The operational experience obtained during the period of these studies has provided some insight into the desirable characteristics and possible limitations of any future spectrometer design and this information is considered in some detail. (author)

  5. SMARTS - a spectrometer for strain measurement in engineering materials

    Energy Technology Data Exchange (ETDEWEB)

    Bourke, M.A.M. [MS H805, Los Alamos National Laboratory, Los Alamos, NM, 87545 (United States); Dunand, D.C. [Department of Materials Science and Engineering, Northwestern University, Cook Hall, Evanston, IL, 60208 (United States); Ustundag, E. [Department of Materials Science, California Institute of Technology, Pasadena, CA 91125 (United States)

    2002-07-01

    A new spectrometer called SMARTS (Spectrometer for Materials Research at Temperature and Stress) has been commissioned at the Los Alamos neutron science center and entered the user program in August of 2002. Its design maximizes capability and throughput for measurements of (a) residual macrostrain in engineering components and (b) in situ loading. This paper describes some aspects of the instrument. (orig.)

  6. SMARTS - a spectrometer for strain measurement in engineering materials

    CERN Document Server

    Bourke, M A M; Ustundag, E

    2002-01-01

    A new spectrometer called SMARTS (Spectrometer for Materials Research at Temperature and Stress) has been commissioned at the Los Alamos neutron science center and entered the user program in August of 2002. Its design maximizes capability and throughput for measurements of (a) residual macrostrain in engineering components and (b) in situ loading. This paper describes some aspects of the instrument. (orig.)

  7. Calibration of a compact magnetic proton recoil neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jianfu, E-mail: zhang_jianfu@163.com [School of Nuclear Science and Technology, Xi' an Jiaotong University, Xi' an 710049 (China); Northwest Institute of Nuclear Technology, Xi' an 710024 (China); Ouyang, Xiaoping; Zhang, Xianpeng [School of Nuclear Science and Technology, Xi' an Jiaotong University, Xi' an 710049 (China); Northwest Institute of Nuclear Technology, Xi' an 710024 (China); Ruan, Jinlu [Northwest Institute of Nuclear Technology, Xi' an 710024 (China); Zhang, Guoguang [Applied Institute of Nuclear Technology, China Institute of Atomic Energy, Beijing 102413 (China); Zhang, Xiaodong [Northwest Institute of Nuclear Technology, Xi' an 710024 (China); Qiu, Suizheng, E-mail: szqiu@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Liang; Liu, Jinliang; Song, Jiwen; Liu, Linyue; Yang, Shaohua [Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

    2016-04-21

    Magnetic proton recoil (MPR) neutron spectrometer is considered as a powerful instrument to measure deuterium–tritium (DT) neutron spectrum, as it is currently used in inertial confinement fusion facilities and large Tokamak devices. The energy resolution (ER) and neutron detection efficiency (NDE) are the two most important parameters to characterize a neutron spectrometer. In this work, the ER calibration for the MPR spectrometer was performed by using the HI-13 tandem accelerator at China Institute of Atomic Energy (CIAE), and the NDE calibration was performed by using the neutron generator at CIAE. The specific calibration techniques used in this work and the associated accuracies were discussed in details in this paper. The calibration results were presented along with Monte Carlo simulation results.

  8. Gas-phase ion-molecule reactions and high-pressure mass spectrometer, 1

    International Nuclear Information System (INIS)

    Hiraoka, Kenzo

    1977-01-01

    The reasons for the fact that the research in gas-phase ion-molecule reactions, to which wide interest is shown, have greatly contributed to the physical and chemical fields are that, first it is essential in understanding general phenomena concerning ions, second, it can furnish many unique informations in the dynamics of chemical reactions, and third, usefulness of '' chemical ionization'' methods has been established as its application to chemical analysis. In this review, the history and trend of studies and equipments in gas-phase ion-molecule reactions are surveyed. The survey includes the chemical ionization mass spectrometer for simultaneously measuring the positive and negative ions utilizing a quadrupole mass spectrometer presented by Hunt and others, flowing afterglow method derived from the flowing method which traces neutral chemical species mainly optically, ion cyclotron resonance mass spectrometer, trapped ion mass spectrometer and others. Number of reports referred to ion-molecule reactions issued during the last one year well exceeds the total number of reports concerning mass spectrometers presented before 1955. This truly shows how active the research and development are in this field. (Wakatsuki, Y.)

  9. Electrostatic Spectrometer for Mars Rover Wheel

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop a simple electrostatic spectrometer that can be mounted on the wheels of a Mars rover to continuously and unobtrusively determine the mineral composition and...

  10. Spectrometer for external detection of magnetic and related double resonance

    International Nuclear Information System (INIS)

    Sagalyn, P.L.; Alexander, M.N.

    1977-01-01

    The patent relates to an improvement in nuclear magnetic resonance spectrometer apparatus. It consists of a spectrometer which utilizes separate materials containing, respectively, sample and detector spin systems as opposed to one in which the sample and detector spins are contained in the same single material

  11. Analysis of noise in energy-dispersive spectrometers using time-domain methods

    CERN Document Server

    Goulding, F S

    2002-01-01

    This paper presents an integrated time domain approach to the optimization of the signal-to-noise ratio in all spectrometer systems that contain a detector that converts incoming quanta of radiation into electrical pulse signals that are amplified and shaped by an electronic pulse shaper. It allows analysis of normal passive pulse shapers as well as time-variant systems where switching of shaping elements occurs in synchronism with the signal. It also deals comfortably with microcalorimeters (sometimes referred to as bolometers), where noise-determining elements, such as the temperature-sensing element's resistance and temperature, change with time in the presence of a signal. As part of the purely time-domain approach, a new method of calculating the Johnson noise in resistors using only the statistics of electron motion is presented. The result is a time-domain analog of the Nyquist formula.

  12. Incidence of centrally positioned nuclei in mouse masticatory muscle fibers

    DEFF Research Database (Denmark)

    Vilmann, A; Vilmann, H; Kirkeby, S

    1989-01-01

    Cross-sections of normal digastric, temporalis and masseter muscles from 7- and 30-week-old mice were studied for centrally positioned nuclei. Such nuclei were inhomogeneously distributed throughout each muscle and varied markedly between specimens. The incidence of centrally positioned nuclei in...

  13. View of the Axial Field Spectrometer

    CERN Multimedia

    1980-01-01

    The Axial Field Spectrometer, with the vertical uranium/scintillator calorimeter and the central drift chamber retracted for service. One coil of the Open Axial Field Magnet is just visible to the right.

  14. Inside the ETH spectrometer magnet

    CERN Multimedia

    1974-01-01

    The ETH spectrometer magnet being prepared for experiment S134, which uses a frozen spin polarized target to study the associated production of a kaon and a lambda by negative pions interacting with protons (CERN-ETH, Zurich-Helsinki-Imperial College, London-Southampton Collaboration). (See Photo Archive 7406316)

  15. High speed, High resolution terahertz spectrometers

    International Nuclear Information System (INIS)

    Kim, Youngchan; Yee, Dae Su; Yi, Miwoo; Ahn, Jaewook

    2008-01-01

    A variety of sources and methods have been developed for terahertz spectroscopy during almost two decades. Terahertz time domain spectroscopy (THz TDS)has attracted particular attention as a basic measurement method in the fields of THz science and technology. Recently, asynchronous optical sampling (AOS)THz TDS has been demonstrated, featuring rapid data acquisition and a high spectral resolution. Also, terahertz frequency comb spectroscopy (TFCS)possesses attractive features for high precision terahertz spectroscopy. In this presentation, we report on these two types of terahertz spectrometer. Our high speed, high resolution terahertz spectrometer is demonstrated using two mode locked femtosecond lasers with slightly different repetition frequencies without a mechanical delay stage. The repetition frequencies of the two femtosecond lasers are stabilized by use of two phase locked loops sharing the same reference oscillator. The time resolution of our terahertz spectrometer is measured using the cross correlation method to be 270 fs. AOS THz TDS is presented in Fig. 1, which shows a time domain waveform rapidly acquired on a 10ns time window. The inset shows a zoom into the signal with 100ps time window. The spectrum obtained by the fast Fourier Transformation (FFT)of the time domain waveform has a frequency resolution of 100MHz. The dependence of the signal to noise ratio (SNR)on the measurement time is also investigated

  16. Study and outlook of Dimuon spectrometer of ALICE experiment at LHC

    International Nuclear Information System (INIS)

    1997-01-01

    The Dimuon spectrometer and its functional integration in the ALICE experiment, planned to work by the Large Hadron Collider at CERN, is briefly presented. The detection assembly consists of a hadron absorber placed near the interaction location, followed by a large dipole superconducting magnet of 4 m aperture and 3 T.m field integral for muon analysis in the rapidity range 2 to 4. The muon tracking is ensured by 5 detection stations bunching 1 million electronic paths on a total detection area of about 100 m 2 . The muon trigger system consists of 4 detection levels ensuring a 10 3 rejection of the incident hadrons. SUBATECH is implied in the tracking and trigger domains of the project. The tracking parameters, relating to spatial resolution, chamber efficiency, magnetic field integral, homogeneity, absorber composition, etc., were optimized in the laboratory. This technical effort was followed by further development of tracking chambers of the spectrometer, based on the MICROMEGAS (MICRO-MEsh-GAseous Structure) detector, conceived by G.Charpak, characterized by its fast response (200 ns) and high position resolution (σ = 100 μm). Larger detectors, with areas of the order of 1 m 2 , as well as, the optimization of readout electronics and associated data acquisition systems are the current preoccupations of a group of 3 physicists and 4 engineers and technicians. A second level muon trigger system was designed to obtain the invariant mass reconstruction for all the muons pairs that cross the first level Pt threshold. After a number of preparing simulations of the trigger system the design of the second level trigger electronics is now to be realized. This work is carried out by two assistant researchers, a post-doctoral researcher and an engineer

  17. Monte Carlo simulation of the resolution volume for the SEQUOIA spectrometer

    Directory of Open Access Journals (Sweden)

    Granroth G.E.

    2015-01-01

    Full Text Available Monte Carlo ray tracing simulations, of direct geometry spectrometers, have been particularly useful in instrument design and characterization. However, these tools can also be useful for experiment planning and analysis. To this end, the McStas Monte Carlo ray tracing model of SEQUOIA, the fine resolution fermi chopper spectrometer at the Spallation Neutron Source (SNS of Oak Ridge National Laboratory (ORNL, has been modified to include the time of flight resolution sample and detector components. With these components, the resolution ellipsoid can be calculated for any detector pixel and energy bin of the instrument. The simulation is split in two pieces. First, the incident beamline up to the sample is simulated for 1 × 1011 neutron packets (4 days on 30 cores. This provides a virtual source for the backend that includes the resolution sample and monitor components. Next, a series of detector and energy pixels are computed in parallel. It takes on the order of 30 s to calculate a single resolution ellipsoid on a single core. Python scripts have been written to transform the ellipsoid into the space of an oriented single crystal, and to characterize the ellipsoid in various ways. Though this tool is under development as a planning tool, we have successfully used it to provide the resolution function for convolution with theoretical models. Specifically, theoretical calculations of the spin waves in YFeO3 were compared to measurements taken on SEQUOIA. Though the overall features of the spectra can be explained while neglecting resolution effects, the variation in intensity of the modes is well described once the resolution is included. As this was a single sharp mode, the simulated half intensity value of the resolution ellipsoid was used to provide the resolution width. A description of the simulation, its use, and paths forward for this technique will be discussed.

  18. Brightness-normalized Partial Least Squares Regression for hyperspectral data

    International Nuclear Information System (INIS)

    Feilhauer, Hannes; Asner, Gregory P.; Martin, Roberta E.; Schmidtlein, Sebastian

    2010-01-01

    Developed in the field of chemometrics, Partial Least Squares Regression (PLSR) has become an established technique in vegetation remote sensing. PLSR was primarily designed for laboratory analysis of prepared material samples. Under field conditions in vegetation remote sensing, the performance of the technique may be negatively affected by differences in brightness due to amount and orientation of plant tissues in canopies or the observing conditions. To minimize these effects, we introduced brightness normalization to the PLSR approach and tested whether this modification improves the performance under changing canopy and observing conditions. This test was carried out using high-fidelity spectral data (400-2510 nm) to model observed leaf chemistry. The spectral data was combined with a canopy radiative transfer model to simulate effects of varying canopy structure and viewing geometry. Brightness normalization enhanced the performance of PLSR by dampening the effects of canopy shade, thus providing a significant improvement in predictions of leaf chemistry (up to 3.6% additional explained variance in validation) compared to conventional PLSR. Little improvement was made on effects due to variable leaf area index, while minor improvement (mostly not significant) was observed for effects of variable viewing geometry. In general, brightness normalization increased the stability of model fits and regression coefficients for all canopy scenarios. Brightness-normalized PLSR is thus a promising approach for application on airborne and space-based imaging spectrometer data.

  19. Magnetic spectrometer control system

    International Nuclear Information System (INIS)

    Lecca, L.A.; Di Paolo, Hugo; Fernandez Niello, Jorge O.; Marti, Guillermo V; Pacheco, Alberto J.; Ramirez, Marcelo

    2003-01-01

    The design and implementation of a new computerized control system for the several devices of the magnetic spectrometer at TANDAR Laboratory is described. This system, as a main difference from the preexisting one, is compatible with almost any operating systems of wide spread use available in PC. This allows on-line measurement and control of all signals from any terminal of a computer network. (author)

  20. Silicon Microleaks for Inlets of Mass Spectrometers

    Science.gov (United States)

    Harpold, Dan; Hasso, Niemann; Jamieson, Brian G.; Lynch, Bernard A.

    2009-01-01

    Microleaks for inlets of mass spectrometers used to analyze atmospheric gases can be fabricated in silicon wafers by means of photolithography, etching, and other techniques that are commonly used in the manufacture of integrated circuits and microelectromechanical systems. The microleaks serve to limit the flows of the gases into the mass-spectrometer vacuums to specified very small flow rates consistent with the capacities of the spectrometer vacuum pumps. There is a need to be able to precisely tailor the dimensions of each microleak so as to tailor its conductance to a precise low value. (As used here, "conductance" signifies the ratio between the rate of flow in the leak and the pressure drop from the upstream to the downstream end of the leak.) To date, microleaks have been made, variously, of crimped metal tubes, pulled glass tubes, or frits. Crimped-metal and pulled-glass-tube microleaks cannot readily be fabricated repeatably to precise dimensions and are susceptible to clogging with droplets or particles. Frits tend to be differentially chemically reactive with various gas constituents and, hence, to distort the gas mixtures to be analyzed. The present approach involving microfabrication in silicon largely overcomes the disadvantages of the prior approaches.

  1. Setting up and performance of a laser enhanced ionisation spectrometer

    International Nuclear Information System (INIS)

    Chandola, L.C.; Khanna, P.P.; Razvi, M.A.N.

    1990-01-01

    A laser enhanced ionisation (LEI) spectrometer has been successfuly set up around an excimer laser pumped dye laser. The performance of the spectrometer has been tested by analysing sodium in water solutions. A straight line working curve has been obtained in the concentration range of 1-1000 ng/ml of Na. The effect of parameters like laser power, ion collector electrode voltage and the load resistance on LEI signals has been investigated. The spectrometer is useful not only for analytical purposes but also for laser spectroscopic studies of species formed in flames, study of phenomenon of combustion etc. (author). 1 tab ., 10 figs., 5 refs

  2. Miniaturized NIR scanning grating spectrometer for use in mobile phones

    Science.gov (United States)

    Knobbe, Jens; Pügner, Tino; Grüger, Heinrich

    2016-05-01

    An extremely miniaturized scanning grating spectrometer at the size of a sugar cube has been developed at Fraunhofer IPMS. To meet the requirements for the integration into a mobile phone a new system approach has been pursued. The key component within the system is a silicon-based deflectable diffraction grating with an integrated driving mechanism. A first sample of the new spectrometer was built and characterized. It was found to have a spectral range from 950 nm to 1900 nm at a resolution of 10 nm. The results show that the performance of the new MEMS spectrometer is in good agreement with the requirements for mobile phone integration.

  3. Development and study of airborne spectrometer system being compatible with nuclear emergency monitoring

    International Nuclear Information System (INIS)

    Jiangqi, Fang; Huaiwu, Wang; Mingkao, Hu; Renkang, Gu

    2002-01-01

    The exploitation and use of nuclear energy are of great importance to developing of national economy and maintaining state security. But it also has a possibility of serious accident. Based on the principles of airborne gamma ray spectrometry in the uranium exploration, nuclear emergency monitoring has been developed. This method has high sensitivity to the radioactive nuclides in the air and on the ground, and with the advantage of fast measuring in large area. Hence, in the middle of 1980s, some developed countries began to survey the scope and degree of nuclear accident contamination and environmental radiation level monitoring in the surrounding nuclear facilities, it can also be used to search for the lost radioactive sources. According to the actual situation and compatible guideline, National Nuclear Emergency Office consigned this project to our Center. After development and study on the Airborne gamma ray spectrometer system associated NaI(Tl) used for the uranium exploration, a compatible spectrometer system associated NaI(Tl) was established in a short period by us, which can fulfill airborne nuclear emergency survey basically. In normal situation, it was proved that the start-up time is less than two hours including transport to the airport. The system has high sensitivity to radioactive plume of 41 Ar and can respond rapidly to artificial sources, such as 192 Ir, 60 Co, 137 Cs and 131 I etc

  4. Application of MSS-neutron spin echo spectrometer to pulsed neutron sources

    International Nuclear Information System (INIS)

    Tasaki, S.; Ebisawa, T.; Hino, M.; Kawai, T.

    2001-01-01

    A multilayer spin splitter (MSS) is a neutron device that gives phase difference between field-parallel and -antiparallel spin component of a superposing state. Since the phase difference is equivalent to the Larmor precession angle, MSS enables us to construct a new type of neutron spin echo (NSE) spectrometer. The new NSE spectrometer has its properties that 1. since the phase shift is neutron flight path length, the spectrometer can be drastically small, 2. the neutron spin echo time is proportional to the neutron wavelength. (author)

  5. Fabrication and testing of the recoil mass spectrometer at Bombay ...

    Indian Academy of Sciences (India)

    A recoil mass spectrometer (RMS) has been designed, fabricated and installed ... first order and only mass dispersion is obtained at the focal plane of the ... more details, like, the specifications and a typical beam profile through the ... Further experiments are now in progress to characterize the spectrometer, i.e., to measure.

  6. The story of a spectrometer

    International Nuclear Information System (INIS)

    Butcher, P.; Uhrberg, R.

    1995-01-01

    This article describes the development and design of a photoelectron spectrometer for use by researchers using synchrotron radiation. Originally developed for a new beam line at the MAXI Synchrotron at Lund in Sweden, the device has many research applications where its high level of performance is required. (UK)

  7. A proposed neutron spectrometer system for JET

    International Nuclear Information System (INIS)

    Elevant, T.; Hellbom, G.; Scheffel, J.; Malmskog, S.

    1979-12-01

    A neutron spectrometer system is proposed primarily for measurements of ion temperature and density and ion beam energy distribution in extended fusion plasmas like e.g. in JET. Three different spectrometers are involved: time of flight, proton recoil and 3 He. Energy resolutions of a few percent both for DD and DT neutrons are provided. Six order of magnitudes in flux ranges will be covered by the system when employing multi-target systems. A neutron collimator and shielding system will be desirable in order to obtain relevant information. Due to the entire differences in energy and fluxes for DD and DT plasmas a flexible collimator-shielding system is recommended

  8. Neutron spectrometer for improved SNM search.

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. The SeaQuest Spectrometer at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Aidala, C.A.; et al.

    2017-06-29

    The SeaQuest spectrometer at Fermilab was designed to detect oppositely-charged pairs of muons (dimuons) produced by interactions between a 120 GeV proton beam and liquid hydrogen, liquid deuterium and solid nuclear targets. The primary physics program uses the Drell-Yan process to probe antiquark distributions in the target nucleon. The spectrometer consists of a target system, two dipole magnets and four detector stations. The upstream magnet is a closed-aperture solid iron magnet which also serves as the beam dump, while the second magnet is an open aperture magnet. Each of the detector stations consists of scintillator hodoscopes and a high-resolution tracking device. The FPGA-based trigger compares the hodoscope signals to a set of pre-programmed roads to determine if the event contains oppositely-signed, high-mass muon pairs.

  10. Physics with the single arm spectrometer at Fermilab

    International Nuclear Information System (INIS)

    Cutts, D.

    1978-01-01

    The single arm spectrometer is fully instrumented for high-energy counter/wire chamber experiments. After a brief description of the spectrometer, data are shown for the inclusive reactions a + p → a + X and a + p → b + X, where a = π +- , K +- , p, or p-bar, and b is different from a. Considerable attention is devoted to the impact analysis of elastic scattering, although inelastic results are also discussed. Cross sections for a number of interactions are compared. Anticipated experiments are outlined. 16 figures, 2 tables

  11. Environmental radioactivity measurements Using a compton suppression spectrometer

    International Nuclear Information System (INIS)

    Sharshar, T.; Elnimr, T.

    1998-01-01

    The natural and artificial radioactivities of some environmental samples such as soil and vegetables have been studied through gamma-ray spectroscopy with a new constructed compton suppression spectrometer (CSS). The spectrometer consists of a 10% p-type HPGe detector as a main detector, an annular NE-102 A plastic scintillator as a guard detector, and a fast-slow coincidence system employing standard electronic modules for anti-compton operation. This study shows that CSS is a powerful tool for measuring the low level activities of environmental samples

  12. Low energy x-ray spectrometer

    International Nuclear Information System (INIS)

    Woodruff, W.R.

    1981-01-01

    A subkilovolt spectrometer has been produced to permit high-energy-resolution, time-dependent x-ray intensity measurements. The diffracting element is a curved mica (d = 9.95A) crystal. To preclude higher order (n > 1) diffractions, a carbon x-ray mirror that reflects only photons with energies less than approx. 1.1 keV is utilized ahead of the diffracting element. The nominal energy range of interest is 800 to 900 eV. The diffracted photons are detected by a gold-surface photoelectric diode designed to have a very good frequency response, and whose current is recorded on an oscilloscope. A thin, aluminium light barrier is placed between the diffracting crystal and the photoelectric diode detector to keep any uv generated on or scattered by the crystal from illuminating the detector. High spectral energy resolution is provided by many photocathodes between 8- and 50-eV wide placed serially along the diffracted x-ray beam at the detector position. The spectrometer was calibrated for energy and energy dispersion using the Ni Lα 1 2 lines produced in the LLNL IONAC accelerator and in third order using a molybdenum target x-ray tube. For the latter calibration the carbon mirror was replaced by one surfaced with rhodium to raise the cut-off energy to about 3 keV. The carbon mirror reflection dependence on energy was measured using one of our Henke x-ray sources. The curved mica crystal diffraction efficiency was measured on our Low-Energy x-ray (LEX) machine. The spectrometer performs well although some changes in the way the x-ray mirror is held are desirable. 16 figures

  13. Decline in Weight and Incident Mild Cognitive Impairment: Mayo Clinic Study of Aging

    Science.gov (United States)

    Alhurani, Rabe E.; Vassilaki, Maria; Aakre, Jeremiah; Mielke, Michelle M.; Kremers, Walter K.; Machulda, Mary M.; Geda, Yonas E.; Knopman, David S.; Peterson, Ronald C.; Roberts, Rosebud O.

    2016-01-01

    IMPORTANCE Unintentional weight loss has been associated with risk of dementia. Since mild cognitive impairment (MCI) is a prodromal stage for dementia, we sought to evaluate whether changes in weight and body mass index (BMI) may predict incident MCI. OBJECTIVE To investigate the association of change in weight and BMI with risk of MCI. DESIGN, SETTING, AND PARTICIPANTS A population-based, prospective study of participants aged 70 years and older from the Mayo Clinic Study of Aging. Maximum weight and height in midlife (aged 40 to 65 years old) were retrospectively ascertained from the medical records of participants using a medical records linkage system. MAIN OUTCOMES MEASURES Participants were evaluated for cognitive outcomes of normal cognition, MCI, or dementia at baseline and prospectively assessed for incident events at each 15-month evaluation. The association of rate of change in weight and body mass index with risk of MCI was investigated using proportional hazards models. RESULTS Over a mean follow-up of 4.4 years, 524 of 1895 cognitively normal participants developed incident MCI. The mean (standard deviation) rate of weight change per decade from midlife to study entry was greater for individuals who developed incident MCI vs. those who remained cognitively normal (−2.0 (5.1) vs. −1.2 (4.9) kg; p = 0.006). A greater decline in weight per decade was associated with an increased risk of incident MCI (hazard ratio [HR] 95% confidence interval [CI], 1.04 [1.02, 1.06], p weight loss of 5 kg/decade corresponds to a 24% increase in risk of MCI (HR=1.24). Higher decline in BMI per decade was also associated with incident MCI (HR, 1.08, 95% CI = [1.03, 1.13], p = 0.003). CONCLUSIONS AND RELEVANCE These findings suggest that declining weight from midlife to late-life is a marker for MCI and may help identify persons at increased risk for MCI. PMID:26831542

  14. The thermal triple-axis-spectrometer EIGER at the continuous spallation source SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Stuhr, U., E-mail: uwe.stuhr@psi.ch [Laboratory of Neutron Scattering and Imaging, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Roessli, B.; Gvasaliya, S. [Laboratory of Neutron Scattering and Imaging, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Rønnow, H.M. [Laboratory for Quantum Magnetism, Institute of Physics, Ecole Polytechnique Féderale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Filges, U.; Graf, D.; Bollhalder, A.; Hohl, D.; Bürge, R.; Schild, M.; Holitzner, L.; Kaegi, C.; Keller, P.; Mühlebach, T. [Laboratory for Scientific Development and Novel Materials, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland)

    2017-05-01

    EIGER is the new thermal triple-axis-spectrometer at the continuous spallation SINQ at PSI. The shielding of the monochromator consists only of non- or low magnetizable materials, which allows the use of strong magnetic fields with the instrument. This shielding reduces the high energy neutron contamination to a comparable level of thermal spectrometers at reactor sources. The instrument design, the performance and first results of the spectrometer are presented.

  15. Optical design for a breadboard high-resolution spectrometer for SIRTF/IRS

    Science.gov (United States)

    Brown, Robert J.; Houck, James R.; van Cleve, Jeffrey E.

    1996-11-01

    The optical design of a breadboard high resolution infrared spectrometer for the IRS instrument on the SIRTF mission is discussed. The spectrometer uses a crossed echelle grating configuration to cover the spectral region from 10 to 20 micrometer with a resolving power of approximately equals 600. The all reflective spectrometer forms a nearly diffraction limited image of the two dimensional spectrum on a 128 multiplied by 128 arsenic doped silicon area array with 75 micrometer pixels. The design aspects discussed include, grating numerology, image quality, packaging and alignment philosophy.

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

    Energy Technology Data Exchange (ETDEWEB)

    Heusser, G.; Weber, M.; Denz, T.; Hakenmueller, J.; Hofacker, R.; Lackner, R.; Lindner, M.; Maneschg, W.; Reisfelder, M.; Simgen, H.; Schreiner, J.; Stolzenburg, D.; Strecker, H.; Westermann, J. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2013-08-08

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

  17. Do it yourself: optical spectrometer for physics undergraduate instruction in nanomaterial characterization

    International Nuclear Information System (INIS)

    Nuryantini, Ade Yeti; Mahen, Ea Cahya Septia; Sawitri, Asti; Nuryadin, Bebeh Wahid

    2017-01-01

    In this paper, we report on a homemade optical spectrometer using diffraction grating and image processing techniques. This device was designed to produce spectral images that could then be processed by measuring signal strength (pixel intensity) to obtain the light source, transmittance, and absorbance spectra of the liquid sample. The homemade optical spectrometer consisted of: (i) a white LED as a light source, (ii) a cuvette or sample holder, (iii) a slit, (iv) a diffraction grating, and (v) a CMOS camera (webcam). In this study, various concentrations of a carbon nanoparticle (CNP) colloid were used in the particle size sample test. Additionally, a commercial optical spectrometer and tunneling electron microscope (TEM) were used to characterize the optical properties and morphology of the CNPs, respectively. The data obtained using the homemade optical spectrometer, commercial optical spectrometer, and TEM showed similar results and trends. Lastly, the calculation and measurement of CNP size were performed using the effective mass approximation (EMA) and TEM. These data showed that the average nanoparticle sizes were approximately 2.4 nm and 2.5 ± 0.3 nm, respectively. This research provides new insights into the development of a portable, simple, and low-cost optical spectrometer that can be used in nanomaterial characterization for physics undergraduate instruction. (paper)

  18. Research of aerial imaging spectrometer data acquisition technology based on USB 3.0

    Science.gov (United States)

    Huang, Junze; Wang, Yueming; He, Daogang; Yu, Yanan

    2016-11-01

    With the emergence of UAV (unmanned aerial vehicle) platform for aerial imaging spectrometer, research of aerial imaging spectrometer DAS(data acquisition system) faces new challenges. Due to the limitation of platform and other factors, the aerial imaging spectrometer DAS requires small-light, low-cost and universal. Traditional aerial imaging spectrometer DAS system is expensive, bulky, non-universal and unsupported plug-and-play based on PCIe. So that has been unable to meet promotion and application of the aerial imaging spectrometer. In order to solve these problems, the new data acquisition scheme bases on USB3.0 interface.USB3.0 can provide guarantee of small-light, low-cost and universal relying on the forward-looking technology advantage. USB3.0 transmission theory is up to 5Gbps.And the GPIF programming interface achieves 3.2Gbps of the effective theoretical data bandwidth.USB3.0 can fully meet the needs of the aerial imaging spectrometer data transmission rate. The scheme uses the slave FIFO asynchronous data transmission mode between FPGA and USB3014 interface chip. Firstly system collects spectral data from TLK2711 of high-speed serial interface chip. Then FPGA receives data in DDR2 cache after ping-pong data processing. Finally USB3014 interface chip transmits data via automatic-dma approach and uploads to PC by USB3.0 cable. During the manufacture of aerial imaging spectrometer, the DAS can achieve image acquisition, transmission, storage and display. All functions can provide the necessary test detection for aerial imaging spectrometer. The test shows that system performs stable and no data lose. Average transmission speed and storage speed of writing SSD can stabilize at 1.28Gbps. Consequently ,this data acquisition system can meet application requirements for aerial imaging spectrometer.

  19. On a low intensity 241 Am Compton spectrometer for measurement ...

    Indian Academy of Sciences (India)

    In this paper, a new design and construction of a low intensity (100 mCi) 241Am -ray Compton spectrometer is presented. The planar spectrometer is based on a small disc source with the shortest geometry. Measurement of the momentum density of polycrystalline Al is used to evaluate the performance of the new design.

  20. Inexpensive Raman Spectrometer for Undergraduate and Graduate Experiments and Research

    Science.gov (United States)

    Mohr, Christian; Spencer, Claire L.; Hippler, Michael

    2010-01-01

    We describe the construction and performance of an inexpensive modular Raman spectrometer that has been assembled in the framework of a fourth-year undergraduate project (costs below $5000). The spectrometer is based on a 4 mW 532 nm green laser pointer and a compact monochromator equipped with glass fiber optical connections, linear detector…