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Sample records for absorption bgo detector

  1. L3 detector: BGO assembly

    CERN Multimedia

    CERN

    1989-01-01

    Explanation and presentation of its construction ( Feb-March 1989). The detector is a multi-layered cylindrical set of different devices, each of them measuring physical quantities relevant to the reconstruction of the collision under study. The three main outer layers are the electro-magnetic calorimeter (also called BGO because it's made of Bismuth Germanium Oxide), the hadronic calorimeter (HCAL) and the muon detector.

  2. L3 experiment's detector : BGO assembly hall

    CERN Multimedia

    CERN

    1987-01-01

    The detector is a multi-layered cylindrical set of different devices, each of them measuring physical quantities relevant to the reconstruction of the collision under study. The three main outer layers are the electro-magnetic calorimeter (also called BGO because it's made of Bismuth Germanium Oxide), the hadronic calorimeter (HCAL) and the muon detector.

  3. Testing of the BGO Compton-suppression detectors for gammasphere

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Ahmad, I.; Annan, G.A. [and others

    1995-08-01

    Gammasphere, the national {gamma}-ray facility, when completed will consist of 110 Compton-suppressed Ge detectors. The bismuth germanate (BGO) Compton-suppression detector system for each Ge detector consists of one tapered hexagonal BGO side shield and one slotted BGO back plug. Due to the geometry of the array, three types of annular shields are required. These types are referred to as B, C and D, and the array consists of 60, 30 and 20 of these units, respectively. Shield types B, C and D have a hexagonal geometry. They are divided into six optically separate sections, each with its own pair of photomultiplier tubes. Argonne assumed responsibility for the procurement and testing of the BGO Compton-suppression units. We received all detectors from the two vendors. In the past year, twenty-four of the B-type detectors were delivered to Stony Brook for evaluation tests. Since the number of crystals to test is quite large (six per detector), we involved undergraduate students working at ANL under the Department of Educational Programs (DEP) in this effort. The quality of students was excellent, and they played a major role in the performance testing of these detectors. Ninety-nine of the hexagonal side shields and 112 backplug detectors were shipped to LBL for use in Gammasphere. The remaining detectors did not meet the performance criteria when they were first delivered and tested and are either at the vendor being repaired or were returned to us for retesting. We anticipate that the remaining detectors will be ready for use in Gammasphere within the next few months.

  4. Comparison of LSO and BGO block detectors for prompt gamma imaging in ion beam therapy

    Science.gov (United States)

    Hueso-González, F.; Biegun, A. K.; Dendooven, P.; Enghardt, W.; Fiedler, F.; Golnik, C.; Heidel, K.; Kormoll, T.; Petzoldt, J.; Römer, K. E.; Schwengner, R.; Wagner, A.; Pausch, G.

    2015-09-01

    A major weakness of ion beam therapy is the lack of tools for verifying the particle range in clinical routine. The application of the Compton camera concept for the imaging of prompt gamma rays, a by-product of the irradiation correlated to the dose distribution, is a promising approach for range assessment and even three-dimensional in vivo dosimetry. Multiple position sensitive gamma ray detectors arranged in scatter and absorber planes, together with an imaging algorithm, are required to reconstruct the prompt gamma emission density map. Conventional block detectors deployed in Positron Emission Tomography (PET), which are based on Lu2SiO5:Ce (LSO) and Bi4Ge3O12 (BGO) scintillators, are suitable candidates for the absorber of a Compton camera due to their high density and absorption efficiency with respect to the prompt gamma energy range (several MeV). We compare experimentally LSO and BGO block detectors in clinical-like radiation fields in terms of energy, spatial and time resolution. The high energy range compensates for the low light yield of the BGO material and boosts significantly its performance compared to the PET scenario. Notwithstanding the overall superiority of LSO, BGO catches up in the field of prompt gamma imaging and can be considered as a competitive alternative to LSO for the absorber plane due to its lower price and the lack of intrinsic radioactivity.

  5. Response of a BGO detector to photon and neutron sources simulations and measurements

    CERN Document Server

    Vincke, H H; Fabjan, Christian Wolfgang; Otto, T

    2002-01-01

    In this paper Monte Carlo simulations (FLUKA) and measurements of the response of a BGO detector are reported. %For the measurements different radioactive sources were used to irradiate the BGO crystal. For the measurements three low-energy photon emitters $\\left({}^{60}\\rm{Co},\\right.$ ${}^{54}\\rm{Mn},$ $\\left. {}^{137}\\rm{Cs}\\right)$ were used to irradiate the BGO from various distances and angles. The neutron response was measured with an Am--Be neutron source. Simulations of the experimental irradiations were carried out. Our study can also be considered as a benchmark for FLUKA in terms of its reliability to predict the detector response of a BGO scintillator.

  6. BGO Readout with Photodiodes as a Soft gamma-Ray Detector at -30C

    Energy Technology Data Exchange (ETDEWEB)

    Nakamoto, T.

    2005-01-21

    BGO is expected to be plausible devices for soft gamma-ray detectors, because of a high detection efficiency for soft gamma-rays. Here we report on the good performance of BGO readout with PIN-photodiode or avalanche photodiode as a soft gamma-ray detector. We confirmed that the signal output of BGO becomes comparable to that of GSO when it is readout with photodiodes due to better matching between emission wavelength of BGO and quantum efficiency of photodiode. The energy resolution of 6.2% and 3.4% for 662 keV and 1836 keV, respectively, gamma-rays at -30 C is obtained with the combination of the 5 x 5 x 5 mm{sup 3} cube BGO and the Hamamatsu avalanche photodiode (APD) S8664-55. In this combination, the lowest detectable energy is found to be {approx}10 keV. These performances are better than that obtained with Photomultiplier tube (PMT), and our results increase many possible applications of BGO readout with photodiodes as soft gamma-ray detectors.

  7. Numerical simulations on efficiency and measurement of capabilities of BGO detectors for high energy gamma ray

    CERN Document Server

    Wen Wan Xin

    2002-01-01

    The energy resolution and time resolution of two phi 75 x 100 BGO detectors for high energy gamma ray newly made were measured with sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co resources. The two characteristic gamma rays of high energy emitted from the thermal neutron capture of germanium in BGO crystal were used for the energy calibration of gamma spectra. The intrinsic photopeak efficiency, single escape probability and double escape probabilities of BGO detectors in photon energy range of 4-30 MeV are numerically calculated with GEANT code. The real count response and count ratio of the uniformly distributed incident photons in energy range of 0-30 MeV are also calculated. The distortion of gamma spectra caused by the photon energy loss extension to lower energy in detection medium is discussed

  8. Low energy prompt gamma-ray tests of a large volume BGO detector

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, A.A., E-mail: aanaqvi@kfupm.edu.sa [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Kalakada, Zameer [Department of Civil Engineering, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Al-Anezi, M.S.; Raashid, M.; Khateeb-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Maslehuddin, M. [Center for Engineering Research, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Garwan, M.A. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

    2012-01-15

    Tests of a large volume Bismuth Germinate (BGO) detector were carried out to detect low energy prompt gamma-rays from boron and cadmium-contaminated water samples using a portable neutron generator-based Prompt Gamma Neutron Activation Analysis (PGNAA) setup. Inspite of strong interference between the sample- and the detector-associated prompt gamma-rays, an excellent agreement has been observed between the experimental and calculated yields of the prompt gamma-rays, indicating successful application of the large volume BGO detector in the PGNAA analysis of bulk samples using low energy prompt gamma-rays. - Highlights: Black-Right-Pointing-Pointer Performance tests of a portable neutron generator based PGNAA setup for field measurement. Black-Right-Pointing-Pointer Application of large volume BGO detector in prompt gamma analysis of bulk samples utilizing low energy prompt-gamma rays. Black-Right-Pointing-Pointer Study of interference of boron and cadmium prompt gamma-rays from bulk samples with BGO detector background spectrum.

  9. The calibration and electron energy reconstruction of the BGO ECAL of the DAMPE detector

    CERN Document Server

    Zhang, Zhiyong; Dong, Jianing; Wei, Yifeng; Wen, Sicheng; Zhang, Yunlong; Li, Zhiying; Feng, Changqing; Gao, Shanshan; Shen, ZhongTao; Zhang, Deliang; Zhang, Junbin; Wang, Qi; Ma, SiYuan; Yang, Di; Jiang, Di; Chen, Dengyi; Hu, Yiming; Huang, Guangshun; Wang, Xiaolian; Xu, Zizong; Liu, Shubin; An, Qi; Gong, Yizhong

    2016-01-01

    The DArk Matter Particle Explorer (DAMPE) is a space experiment designed to search for dark matter indirectly by measuring the spectra of photons, electrons, and positrons up to 10 TeV. The BGO electromagnetic calorimeter (ECAL) is its main sub-detector for energy measurement. In this paper, the instrumentation and development of the BGO ECAL is briefly described. The calibration on the ground, including the pedestal, minimum ionizing particle (MIP) peak, dynode ratio, and attenuation length with the cosmic rays and beam particles is discussed in detail. Also, the energy reconstruction results of the electrons from the beam test are presented.

  10. The calibration and electron energy reconstruction of the BGO ECAL of the DAMPE detector

    Science.gov (United States)

    Zhang, Zhiyong; Wang, Chi; Dong, Jianing; Wei, Yifeng; Wen, Sicheng; Zhang, Yunlong; Li, Zhiying; Feng, Changqing; Gao, Shanshan; Shen, ZhongTao; Zhang, Deliang; Zhang, Junbin; Wang, Qi; Ma, SiYuan; Yang, Di; Jiang, Di; Chen, Dengyi; Hu, Yiming; Huang, Guangshun; Wang, Xiaolian; Xu, Zizong; Liu, Shubin; An, Qi; Gong, Yizhong

    2016-11-01

    The DArk Matter Particle Explorer (DAMPE) is a space experiment designed to search for dark matter indirectly by measuring the spectra of photons, electrons, and positrons up to 10 TeV. The BGO electromagnetic calorimeter (ECAL) is its main sub-detector for energy measurement. In this paper, the instrumentation and development of the BGO ECAL is briefly described. The calibration on the ground, including the pedestal, minimum ionizing particle (MIP) peak, dynode ratio, and attenuation length with the cosmic rays and beam particles is discussed in detail. Also, the energy reconstruction results of the electrons from the beam test are presented.

  11. Initial characterization of a position-sensitive photodiode/BGO detector for PET (positron emission tomography)

    Energy Technology Data Exchange (ETDEWEB)

    Derenzo, S.E.; Moses, W.W.; Jackson, H.G.; Turko, B.T.; Cahoon, J.L.; Geyer, A.B.; Vuletich, T.

    1988-11-01

    We present initial results of a position-sensitive photodiode/BGO detector for high resolution, multi-layer positron emission tomography (PET). Position sensitivity is achieved by dividing the 3 mm /times/ 20 mm rectangular photosensitive area along the diagonal to form two triangular segments. Each segment was individually connected to a low-noise amplifier. The photodiodes and crystals were cooled to /minus/100/degree/C to reduce dark current and increase the BGO signal. With an amplifier peaking time of 17 ..mu..sec, the sum of the signals (511 keV photopeak) was 3200 electrons with a full width at half maximum (fwhm) of 750 electrons. The ratio of one signal to the sum determined the depth of interaction with a resolution of 11 mm fwhm. 27 refs., 7 figs.

  12. Response of BGO detectors to photons of 3-50 MeV energy

    Science.gov (United States)

    Matulewicz, T.; Henning, W.; Emling, H.; Freifelder, R.; Grein, H.; Grosse, E.; Herrmann, N.; Holzmann, R.; Kulessa, R.; Simon, R. S.; Wollersheim, H. J.; Schoch, B.; Vogt, J.; Wilhelm, M.; Kratz, J. V.; Schmidt, R.; Janssens, R. V. F.

    1993-02-01

    The response of an array of 7 hexagonal BGO detectors each 7.5 cm long (6.7 radiation lengths) with 3.6 cm side-to-side distance was measured using monochromatic photons from the tagged-photon facility at the electron accelerator MAMI A at Mainz. The experimental spectra of the deposited energy for a single detector and for the array of seven modules compare very well with the predictions of Monte Carlo shower simulations using the code GEANT3. Significant improvement of the energy resolution is observed for the summed energy spectra compared to the resolution of a single module. This improvement deteriorates at higher photon energies because the length of the detector is not sufficient to absorb the forward component of the electromagnetic shower.

  13. Response of BGO detectors to photons of 3-50 MeV energy

    Energy Technology Data Exchange (ETDEWEB)

    Matulewicz, T.; Henning, W.; Emling, H.; Freifelder, R.; Grein, H.; Grosse, E.; Herrmann, N.; Holzmann, R.; Kulessa, R.; Simon, R.S.; Wollersheim, H.J. (Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany)); Schoch, B.; Vogt, J.; Wilhelm, M. (Inst. fuer Kernphysik, Univ. Mainz (Germany)); Kratz, J.V.; Schmidt, R. (Inst. fuer Kernchemie, Univ. Mainz (Germany)); Janssens, R.V.F. (Argonne National Lab., IL (United States))

    1993-02-01

    The response of an array of 7 hexagonal BGO detectors each 7.5 cm long (6.7 radiation lengths) with 3.6 cm side-to-side distance was measured using monochromatic photons from the tagged-photon facility at the electron accelerator MAMI A at Mainz. The experimental spectra of the deposited energy for a single detector and for the array of seven modules compare very well with the predictions of Monte Carlo shower simulations using the code GEANT3. Significant improvement of the energy resolution is observed for the summed energy spectra compared to the resolution of a single module. This improvement deteriorates at higher photon energies because the length of the detector is not sufficient to absorb the forward component of the electromagnetic shower. (orig.).

  14. A quantitative PGNAA study for use in aqueous solution measurements using Am–Be neutron source and BGO scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ghal-Eh, N., E-mail: ghal-eh@du.ac.ir [School of Physics, Damghan University, P.O. Box 36716-41167, Damghan (Iran, Islamic Republic of); Ahmadi, P. [School of Physics, Damghan University, P.O. Box 36716-41167, Damghan (Iran, Islamic Republic of); Doost-Mohammadi, V. [Nuclear Science and Technology Research Center, AEOI, P.O. Box 11365-8486, Tehran (Iran, Islamic Republic of)

    2016-02-01

    A prompt gamma neutron activation analysis (PGNAA) system including an Am–Be neutron source and BGO scintillation detector are used for quantitative analysis of bulk samples. Both Monte Carlo-simulated and experimental data are considered as input data libraries for two different procedures based on neural network and least squares methods. The results confirm the feasibility and precision of the proposed methods.

  15. Prompt gamma tests of LaBr{sub 3}:Ce and BGO detectors for detection of hydrogen, carbon and oxygen in bulk samples

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, A.A., E-mail: aanaqvi@kfupm.edu.sa [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Al-Matouq, Fares A.; Khiari, F.Z. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Isab, A.A. [Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Rehman, Khateeb-ur; Raashid, M. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

    2012-08-21

    Prompt gamma ray tests of cylindrical lanthanum halide (LaBr{sub 3}:Ce) and bismuth germanate (BGO) gamma ray detectors have been carried out for detection of hydrogen, carbon and oxygen concentrations in bulk samples via inelastic scattering of neutrons using a 14 MeV neutron-based prompt gamma neutron activation analysis setup. Regardless of its intrinsic activity, the LaBr{sub 3}:Ce detector showed superior performance than the BGO detector for the detection of hydrogen, carbon and oxygen concentrations in benzene, water, toluene, propanol, ethanol and methanol bulk samples. The BGO detector has a large concentration of oxygen in its detector material and is consequently less sensitive for oxygen detection in bulk samples. Hence, it is not a suitable choice for oxygen determination in bulk samples.

  16. Construction of a CsI(Tl)-BGO phoswitch detector for the detection of high energy protons at GANIL; Construction d`un detecteur phoswich CsI(Tl)-BGO pour la detection de protons de haute energie au GANIL

    Energy Technology Data Exchange (ETDEWEB)

    Lautridou, P.; Eudes, P.; Germain, M.; Guilbault, F.; Laville, J.L.; Rahmani, A.; Reposeur, T. [Laboratoire de Physique Subatomique et des Technologies Associees - SUBATECH, Centre National de la Recherche Scientifique, 44 - Nantes (France)

    1997-10-01

    An attractive concept of phoswitch detector composed of CsI(Tl) and BGO crystals has been developed in our laboratory. This detector combines the phoswitch technique with the intrinsic capabilities of pulse shape discrimination of CsI(Tl). It can detect particles of Z=3 with energies ranging from a few MeV/nucleon up to several hundred MeV/nucleon. The experimental certification of this new concept has been tested at GANIL where high energy light particles produced in the reaction {sup 58} Ni + Al (74 MeV/A) were detected at an angle of 15 deg.. The identification matrix Q{sub slow} versus Q{sub fast} makes evident two operation principles of the detector. On the diagonal the particles ({gamma},p,d,t,{sup 3,4} He) stopped in CsI form a classical identification picture of this crystal. A very good mass based identification was obtained for Z=1 (A=1,2,3), Z=2 (A=3,4) and Z=3 (A=6,7). In the upper part, the particles (p,d,t) stopped in the BGO after passing through CsI are perfectly identified by the additional contribution of the BGO on the axis Q{sub fast}. The proton energies in the reversal point as well as in the detected peak are determined 5 refs.

  17. Performance Characteristics of BGO Detectors for a Low Cost Preclinical PET Scanner

    OpenAIRE

    2010-01-01

    PETbox is a low-cost benchtop PET scanner dedicated to high throughput preclinical imaging that is currently under development at our institute. This paper presents the design and characterization of the detectors that are used in the PETbox system. In this work, bismuth germanate scintillator was used for the detector, taking advantage of its high stopping power, high photoelectric event fraction, lack of intrinsic background radiation and low cost. The detector block was segmented into a pi...

  18. Performance Characteristics of BGO Detectors for a Low Cost Preclinical PET Scanner.

    Science.gov (United States)

    Zhang, H; Vu, N T; Bao, Q; Silverman, R W; Berry-Pusey, B N; Douraghy, A; Williams, D A; Rannou, F R; Stout, D B; Chatziioannou, A F

    2010-06-01

    PETbox is a low-cost benchtop PET scanner dedicated to high throughput preclinical imaging that is currently under development at our institute. This paper presents the design and characterization of the detectors that are used in the PETbox system. In this work, bismuth germanate scintillator was used for the detector, taking advantage of its high stopping power, high photoelectric event fraction, lack of intrinsic background radiation and low cost. The detector block was segmented into a pixelated array consisting of 20 × 44 elements, with a crystal pitch of 2.2 mm and a crystal cross section of 2 mm × 2 mm. The effective area of the array was 44 mm × 96.8 mm. The array was coupled to two Hamamatsu H8500 position sensitive photomultiplier tubes, forming a flat-panel type detector head with a sensitive area large enough to cover the whole body of a typical laboratory mouse. Two such detector heads were constructed and their performance was characterized. For one detector head, the energy resolution ranged from 16.1% to 38.5% full width at half maximum (FWHM), with a mean of 20.1%; for the other detector head, the energy resolution ranged from 15.5% to 42.7% FWHM, with a mean of 19.6%. The intrinsic spatial resolution was measured to range from 1.55 mm to 2.39 mm FWHM along the detector short axis and from 1.48 mm to 2.33 mm FWHM along the detector long axis, with an average of 1.78 mm. Coincidence timing resolution for the detector pair was measured to be 4.1 ns FWHM. These measurement results show that the detectors are suitable for our specific application.

  19. Gamma-ray multiplicity measurement of the spontaneous fission decay of 252Cf in a segmented HPGe/BGO detector array

    Energy Technology Data Exchange (ETDEWEB)

    Bleuel, D L; Bernstein, L A; Burke, J T; Gibelin, J; Heffner, M D; Mintz, J; Norman, E B; Phair, L; Scielzo, N D; Sheets, S A; Snyderman, N J; Stoyer, M A; Wiedeking, M

    2008-04-23

    Coincident {gamma} rays from a {sup 252}Cf source were measured using an array of six segmented high-purity germanium (HPGe) Clover detectors each enclosed by 16 bismuth-germanate (BGO) detectors. The detectors were arranged in a cubic pattern around a 1 {micro}Ci {sup 252}Cf source to cover a large solid angle for {gamma}-ray measurement with a reasonable reconstruction of the multiplicity. Neutron multiplicity was determined in certain cases by identifying the prompt {gamma} rays from individual fission fragment pairs. Multiplicity distributions from previous experiments and theoretical models were convolved with the response function of the array and compared to the present results. These results suggest a {gamma}-ray multiplicity spectrum broader than previous measurements and models, and provide no evidence of correlation with neutron multiplicity.

  20. Gamma-ray multiplicity measurement of the spontaneous fission of {sup 252}Cf in a segmented HPGe/BGO detector array

    Energy Technology Data Exchange (ETDEWEB)

    Bleuel, D.L., E-mail: bleuel1@llnl.go [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Bernstein, L.A.; Burke, J.T. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Gibelin, J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Heffner, M.D. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Mintz, J. [Nuclear Engineering Department, University of California, Berkeley, CA 94720 (United States); Norman, E.B. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Nuclear Engineering Department, University of California, Berkeley, CA 94720 (United States); Phair, L. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Scielzo, N.D.; Sheets, S.A.; Snyderman, N.J.; Stoyer, M.A. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Wiedeking, M. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2010-12-21

    Coincident {gamma} rays from a {sup 252}Cf source were measured using an array of six segmented high-purity germanium (HPGe) Clover detectors each enclosed by 16 bismuth-germanate (BGO) detectors. The detectors were arranged in a cubic pattern around a 1{mu}Ci{sup 252}Cf source to cover a large solid angle for {gamma}-ray measurement with a reasonable reconstruction of the multiplicity. Neutron multiplicity was determined in certain cases by identifying the prompt {gamma} rays from individual fission fragment pairs. Multiplicity distributions from previous experiments and theoretical models were convolved with the response function of the array and compared to the present results. These results suggest a {gamma}-ray multiplicity spectrum broader than previous measurements and models, and provide no evidence of correlation with neutron multiplicity.

  1. Simulation of the BGO-OD experiment at ELSA

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, Russell [University of Bonn, Physikalisches Institut, Bonn (Germany); Collaboration: BGO-OD-Collaboration

    2011-07-01

    The goal of the BGO Open-Dipole (BGO-OD) project is the systematic investigation of the photoproduction of mesons off the nucleon. These processes are related to the structure of both the mesons and the baryons involved in reactions typical of low-energy hadronic physics. In order to fully understand and accurately interpret the results of the BGO-OD experiment it will be necessary to have a full detector and reaction simulation so that effects from detector resolution and acceptance can be accounted for in the final results. The simulation of the BGO-OD will be be undertaken with the Explora Virtual Monte-Carlo (VMC) software framework. This allows for one common user code to be implemented under Geant4, Geant3 and Fluka. The simulation software is also an analysis tool and such flexibility will be key to an efficient final analysis of the data from the BGO-OD experiment. Presented here are current status of the simulation software for the BGO-OD project and the relevant geometry of the BGO-OD, including the central BGO rugby ball detector with the dual-layer Multiwire Proportional Chambers (MWPCs) and the forward spectrometer, consisting of a large dipole magnet, tracking detectors and the Time-of-Flight walls. Simulation of the magnetic field will also be covered.

  2. BGO* electromagnetic calorimeter

    CERN Multimedia

    CERN

    1988-01-01

    * Short for Bismuth-Germanium-Oxyde, a scintillator of high atomic number Z used in electromagnetic crystal calorimeters. BGO is characterized by fast rise time (a few nanoseconds) and short radiation length (1.11 cm).

  3. Multilayer passive shielding of scintillation detectors based on BGO, NaI(Tl), and stilbene crystals operating in intense neutron fields with an energy of 14.1 MeV

    Science.gov (United States)

    Bystritsky, V. M.; Valkovic, V.; Grozdanov, D. N.; Zontikov, A. O.; Ivanov, I. Zh.; Kopatch, Yu. N.; Krylov, A. R.; Rogov, Yu. N.; Ruskov, I. N.; Sapozhnikov, M. G.; Skoy, V. R.; Shvetsov, V. N.

    2015-03-01

    We discuss the issues related to choosing the optimum type of passive shielding of scintillation detectors based on BGO, NaI(Tl), and stilbene crystals from the direct penetration of neutron radiation with an energy of 14.1 MeV that was emitted isotropically into a solid angle of 4π. A series of experimental measurements of the count-rate suppression factor that may be obtained for the indicated detectors through the use of various shielding filters comprising iron, lead, and borated polyethylene layers with a total thickness not exceeding 50 cm are conducted.

  4. Evaluation of granulated BGO, GSO:Ce, YAG:Ce, CaF sub 2 :Eu and ZnS:Ag for alpha/beta pulse shape discrimination in a flow-cell radiation detector

    CERN Document Server

    Devol, T A; Fjeld, R A

    1999-01-01

    Granulated BGO, GSO:Ce, YAG:Ce, and CaF sub 2 :Eu; CaF sub 2 :Eu coated with a fluorescent polymer, and combinations of coated and uncoated CaF sub 2 :Eu with ZnS:Ag were evaluated for their ability to discriminate between alpha and beta particles in a flow-cell radiation detector. The evaluations were based on the analysis of pulse shape spectra. Various granulated scintillators were packed into flow cell detectors that were coils of 3.0 mm ODx1.5 mm ID fluorinated ethylene propylene Teflon[reg] tubing positioned between dual photomultiplier tubes for analysis. The best pulse shape discrimination was obtained for a combination of equal masses of uncoated CaF sub 2 :Eu (63-90 mu m) and ZnS:Ag (10 mu m), which had a 9% spillover. Additional research is needed to reduce the spillover.

  5. Readout Electronics for BGO Calorimeter of DAMPE: Status during the First Half-year after Launching

    Science.gov (United States)

    Ma, Siyuan; Feng, Changqing; Zhang, Deliang; Wang, Qi

    2016-07-01

    The DAMPE (DArk Matter Particle Explorer) is a scientic satellite which was successfully launched into a 500 Km sun-synchronous orbit, on December 17th, 2015, from the Jiuquan Satellite Launch Center of China. The major scientific objective of DAMPE mission is indirect searching for dark matter by observing high energy primary cosmic rays, especially positrons/electrons and gamma rays with an energy range from 5 GeV to 10 TeV. The BGO (Bismuth Germanate Oxide) calorimeter, which is a critical sub-detector of DAMPE payload, was developed for measuring the energy of cosmic particles, distinguishing positrons/electrons and gamma rays from hadron background, and providing trigger information. It is composed of 308 BGO crystal logs, with the size of 2.5cm*2.5cm*60cm for each log to form a total absorption electromagnetic calorimeter. All the BGO logs are stacked in 14 layers, with each layer consisting of 22 BGO crystal logs and each log is viewed by two Hamamatsu R5610A PMTs (photomultiplier tubes), from both sides respectively. Each PMT incorporates a three dynode pick off to achieve a large dynamic range, which results in 616 PMTs and 1848 signal channels. The main function of readout electronics system, which consists of 16 FEE(Front End Electronics) modules, is to precisely measure the charge of PMT signals and providing "hit" signals. The hit signals are sent to the trigger module of PDPU (Payload Data Process Unit) to generate triggers for the payload. The calibration of the BGO calorimeter is composed of pedestal testing and electronic linear scale, which are executed frequently in the space after launching. The data of the testing is transmitted to ground station in the form of scientific data. The monitor status consists of temperature, current and status words of the FEE, which are measured and recorded every 16 seconds and packed in the engineering data, then transmitted to ground station. The status of the BGO calorimeter can be evaluated by the calibration

  6. Detectors for the Gamma-Ray Resonant Absorption (GRA) Method of Explosives Detection in Cargo: A Comparative Study

    CERN Document Server

    Vartsky, D; Engler, G; Shor, A; Goldschmidt, A; Feldman, G; Bar, D; Orion, I; Wielopolski, L; Vartsky, David; Goldberg, Mark B.; Engler, Gideon; Shor, Asher; Goldschmidt, Aharon; Feldman, Gennady; Bar, Doron; Orion, Itzhak; Wielopolski, Lucian

    2004-01-01

    Gamma-Ray Resonant Absorption (GRA) is an automatic-decision radiographic screening technique that combines high radiation penetration with very good sensitivity and specificity to nitrogenous explosives. The method is particularly well-suited to inspection of large, massive objects (since the incident gamma-ray probe is at 9.17 MeV) such as aviation and marine containers, heavy vehicles and railroad cars. Two kinds of gamma-ray detectors have been employed to date in GRA systems: 1) Resonant-response nitrogen-rich liquid scintillators and 2) BGO detectors. This paper analyses and compares the response of these detector-types to the resonant radiation, in terms of single-pixel figures of merit. The latter are sensitive not only to detector response, but also to accelerator-beam quality, via the properties of the nuclear reaction that produces the resonant gamma-rays. Generally, resonant detectors give rise to much higher nitrogen-contrast sensitivity in the radiographic image than their non-resonant detector ...

  7. The response of a BGO scintillator to relativistic heavy ions

    CERN Document Server

    Matsufuji, N; Komami, H; Kohno, T

    1999-01-01

    The response of a BGO scintillator to He, C, Ne, Si and Ar ions has been studied at incident energies from 120 MeV up to 18 GeV for the first time. The energy of incident beam was changed by inserting an absorber of various thicknesses made of PMMA plates. The primary particles were identified and separated from projectile fragments by using the DELTA E-E counter telescope method. A thin NE102A plastic scintillator and a BGO scintillator were used as a DELTA E counter and a residual E detector, respectively. The energy of the primary particles was deduced by comparing the depth-dose distribution measured by an ionization chamber to those by a theoretical calculation. The light output of the BGO scintillator was found to be linear in this energy region. The dependency of the light output on the particle species was well indexed as a function of log (AZ sup 2).

  8. Commissioning and initial experimental program of the BGO-OD experiment at ELSA

    Directory of Open Access Journals (Sweden)

    Alef S.

    2016-01-01

    Full Text Available BGO-OD is a new meson photoproduction experiment at the ELSA facility of Bonn University. It aims at the investigation of non strange and strange baryon excitations, and is especially designed to be able to detect weekly bound meson-baryon type structures. The setup for the BGO-OD experiment is presented, the characteristics of the photon beam and the detector performances are shown and the initial experimental program is discussed.

  9. Study of the {sup 22}Ne(p,γ){sup 23}Na reaction at LUNA with a 4π BGO summing detector

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, Marcell Peter; Bemmerer, Daniel; Szuecs, Tamas [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Collaboration: LUNA-Collaboration

    2015-07-01

    The {sup 22}Ne(p,γ){sup 23}Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle is active in asymptotic giant branch stars as well as in novae and contributes to the nucleosythesis of neon and sodium isotopes. In order to reduce the uncertainties in the predicted nucleosynthesis yields, new experimental efforts to measure the {sup 22}Ne(p,γ){sup 23}Na cross section directly at the astrophysically relevant energies are needed. In the first, recently completed phase of the LUNA {sup 22}Ne(p,γ){sup 23}Na experiment, selected low-energy resonances were studied with two high-purity germanium detectors. In the present talk, the preparations for the second experimental phase are reported. In this phase, a 4π bismuth germanate summing detector will be used to address the lowest-energy resonances as well as direct capture.

  10. Structure design and enviromental test of BGO calorimeter for satellite DAMPE

    Science.gov (United States)

    Hu, Yiming; Feng, Changqing; Zhang, Yunlong; Chen, Dengyi; Chang, Jin

    2016-07-01

    The Dark Matter Particle Explorer, DAMPE, is a new designed satellite developed for the new Innovation 2020 program of Chinese Academy of Sciences. As the most important payload of China's first scientific satellite for detecting dark matter, the primary purposes of BGO calorimeter is to measure the energy of incident high energy electrons and gamma rays (5GeV-10TeV) and to identify hadron and electronics. BGO calorimeter also provides an important background discriminator by measuring the energy deposition due to the particle shower that produced by the e^{±}, γ and imaging their shower development profile. Structure design of BGO calorimeter is described in this paper. The new designed BGO calorimeter consists of 308 BGO crystals coupled with photomultiplier tubes on its two ends. The envelop size of the BGO calorimeter is 907.5mm×907.5mm×494.5mm,and the weight of which is 1051.4Kg. The most important purpose of mechanical design is how to package so heavy crystals into a detector as required arrangement and to make sure reliability and safety. This paper describes the results of vibration tests using the Flight Module of the BGO Calorimeter for the DAMPE satellite. During the vibration tests, no degradation of the mechanical assembly was observed. After random or sinusoidal vibrations, there was no significant changes of the frequency signatures observed during the modal surveys. The comparison of results of cosmic ray tests before and after the vibration shows no change in the performance of the BGO calorimeter.

  11. Study on Radiation Condition in DAMPE Orbit by Analyzing the Engineering Data of BGO Calorimeter

    Science.gov (United States)

    Feng, Changqing; Liu, Shubin; Zhang, Yunlong; Ma, Siyuan

    2016-07-01

    The DAMPE (DArk Matter Particle Explorer) is a scientific satellite which was successfully launched into a 500 Km sun-synchronous orbit, on December 17th, 2015, from the Jiuquan Satellite Launch Center of China. The major scientific objectives of the DAMPE mission are primary cosmic ray, gamma ray astronomy and dark matter particles, by observing high energy primary cosmic rays, especially positrons/electrons and gamma rays with an energy range from 5 GeV to 10 TeV. The BGO calorimeter is a critical sub-detector of DAMPE payload, for measuring the energy of cosmic particles, distinguishing positrons/electrons and gamma rays from hadron background, and providing trigger information. It utilizes 308 BGO (Bismuth Germanate Oxide) crystal logs with the size of 2.5cm*2.5cm*60cm for each log, to form a total absorption electromagnetic calorimeter. All the BGO logs are stacked in 14 layers, with each layer consisting of 22 BGO crystal logs and each log is viewed by two Hamamatsu R5610A PMTs (photomultiplier tubes), from both sides respectively. In order to achieve a large dynamic range, each PMT base incorporates a three dynode (2, 5, 8) pick off, which results in 616 PMTs and 1848 signal channels. The readout electronics system, which consists of 16 FEE (Front End Electronics) modules, was developed. Its main functions are based on the Flash-based FPGA (Field Programmable Gate Array) chip and low power, 32-channel VA160 and VATA160 ASICs (Application Specific Integrated Circuits) for precisely measuring the charge of PMT signals and providing "hit" signals as well. The hit signals are sent to the trigger module of PDPU (Payload Data Process Unit) and the hit rates of each layer is real-timely recorded by counters and packed into the engineering data, which directly reflect the flux of particles which fly into or pass through the detectors. In order to mitigate the SEU (Single Event Upset) effect in radioactive space environment, certain protecting methods, such as TMR

  12. Optimized Superconducting Nanowire Single Photon Detectors to Maximize Absorptance

    CERN Document Server

    Csete, Maria; Szenes, Andras; Banhelyi, Balazs; Csendes, Tibor; Szabo, Gabor

    2015-01-01

    Dispersion characteristics of four types of superconducting nanowire single photon detectors, nano-cavity-array- (NCA-), nano-cavity-deflector-array- (NCDA-), nano-cavity-double-deflector-array- (NCDDA-) and nano-cavity-trench-array- (NCTA-) integrated (I-A-SNSPDs) devices was optimized in three periodicity intervals commensurate with half-, three-quarter- and one SPP wavelength. The optimal configurations capable of maximizing NbN absorptance correspond to periodicity dependent tilting in S-orientation (90{\\deg} azimuthal orientation). In NCAI-A-SNSPDs absorptance maxima are reached at the plasmonic Brewster angle (PBA) due to light tunneling. The absorptance maximum is attained in a wide plasmonic-pass-band in NCDAI_1/2*lambda-A, inside a flat-plasmonic-pass-band in NCDAI_3/4*lambda-A and inside a narrow plasmonic-band in NCDAI_lambda-A. In NCDDAI_1/2*lambda-A bands of strongly-coupled cavity and plasmonic modes cross, in NCDDAI_3/4*lambda-A an inverted-plasmonic-band-gap develops, while in NCDDAI_lambda-A ...

  13. BGO as a hybrid scintillator / Cherenkov radiator for cost-effective time-of-flight PET

    Science.gov (United States)

    Brunner, S. E.; Schaart, D. R.

    2017-06-01

    Due to detector developments in the last decade, the time-of-flight (TOF) method is now commonly used to improve the quality of positron emission tomography (PET) images. Clinical TOF-PET systems based on L(Y)SO:Ce crystals and silicon photomultipliers (SiPMs) with coincidence resolving times (CRT) between 325 ps and 400 ps FWHM have recently been developed. Before the introduction of L(Y)SO:Ce, BGO was used in many PET systems. In addition to a lower price, BGO offers a superior attenuation coefficient and a higher photoelectric fraction than L(Y)SO:Ce. However, BGO is generally considered an inferior TOF-PET scintillator. In recent years, TOF-PET detectors based on the Cherenkov effect have been proposed. However, the low Cherenkov photon yield in the order of  ˜10 photons per event complicates energy discrimination-a severe disadvantage in clinical PET. The optical characteristics of BGO, in particular its high transparency down to 310 nm and its high refractive index of  ˜2.15, are expected to make it a good Cherenkov radiator. Here, we study the feasibility of combining event timing based on Cherenkov emission with energy discrimination based on scintillation in BGO, as a potential approach towards a cost-effective TOF-PET detector. Rise time measurements were performed using a time-correlated single photon counting (TCSPC) setup implemented on a digital photon counter (DPC) array, revealing a prompt luminescent component likely to be due to Cherenkov emission. Coincidence timing measurements were performed using BGO crystals with a cross-section of 3 mm  ×  3 mm and five different lengths between 3 mm and 20 mm, coupled to DPC arrays. Non-Gaussian coincidence spectra with a FWHM of 200 ps were obtained with the 27 mm3 BGO cubes, while FWHM values as good as 330 ps were achieved with the 20 mm long crystals. The FWHM value was found to improve with decreasing temperature, while the FWTM value showed the opposite trend.

  14. New detector array - the HRIBF Modular Total Absorption Spectrometer

    Science.gov (United States)

    Wolinska-Cichocka, Marzena; Rykaczewski, Krzysztof; Karny, Marek; Kuzniak, Aleksandra; Grzywacz, Robert; Rasco, Charlie; Miller, David; Gross, Carl J.; Johnson, Jim

    2011-10-01

    The construction of a new Modular Total Absorption Spectrometer (MTAS) at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory will be presented. The total absorption gamma spectra measured with MTAS will be used to derive a true beta-feeding pattern and resulting beta strength function for fission products. In particular, the measurements of decay heat released by radioactive nuclei produced in nuclear fuels at power reactors will be performed. MTAS is made up of 19 large NaI(Tl) crystals each encapsulated with a 0.8-mm-thick carbon fiber. There are also two 1-mm- thick Silicon Strip Detectors surrounding a moving tape collector that count beta-energy loss signals. The structure is shielded by more than 1-inch of lead around MTAS which reduces background radiation significantly. MTAS efficiency for full energy deposition of gamma ray approaches nearly 90% for 300 keV gammas and over 75% for a 5 MeV gamma transition. Research supported by the DOE Office of Nuclear Physics.

  15. Strangeness Photoproduction at the BGO-OD Experiment

    CERN Document Server

    Jude, T C; Bayadilov, D; Beck, R; Becker, M; Bella, A; Bielefeldt, P; Boese, S; Braghieri, A; Brinkmann, K; Cole, P; Curciarello, F; De Leo, V; Di Salvo, R; Dutz, H; Elsner, D; Fantini, A; Freyermuth, O; Friedrich, S; Frommberger, F; Ganenko, V; Gervino, G; Ghio, F; Giardina, G; Goertz, S; Gridnev, A; Gutz, E; Hammann, D; Hannappel, J; Hartmann, P; Hillert, W; Ignatov, A; Jahn, R; Joosten, R; Klein, F; Koop, K; Krusche, B; Lapik, A; Sandri, P Levi; Lopatin, I V; Mandaglio, G; Messi, F; Messi, R; Metag, V; Moricciani, D; Mushkarenkov, A; Nanova, M; Nedorezov, V; Novinskiy, D; Pedroni, P; Reitz, B; Romaniuk, M; Rostomyan, T; Rudnev, N; Scheluchin, G; Schmieden, H; Stugelev, A; Sumachev, V; Tarakanov, V; Vegna, V; Walther, D; Watts, D; Zaunick, H; Zimmermann, T

    2015-01-01

    BGO-OD is a newly commissioned experiment to investigate the internal structure of the nucleon, using an energy tagged bremsstrahlung photon beam at the ELSA electron facility. The setup consists of a highly segmented BGO calorimeter surrounding the target, with a particle tracking magnetic spectrometer at forward angles. BGO-OD is ideal for investigating meson photoproduction. The extensive physics programme for open strangeness photoproduction is introduced, and preliminary analysis presented.

  16. Energy response of a novel compact Ge+BGO spectrometer for 4-20 MeV gamma-rays

    CERN Document Server

    Csatlos, M; Bacelar, J C S; Balanda, A; Przygoda, W; Schadmand, S; De Voigt, M J A

    1999-01-01

    The energy response of a novel composite Ge+BGO spectrometer has been measured for high-energy (4-20 MeV) photons. The spectrometer consists of a cooled Ge solid state central detector surrounded by a single BGO scintillator crystal without having interfering materials in between. Good energy resolution (approx 1.7%) combined with a considerable photopeak efficiency (epsilon approx 17%) have been obtained at 15.1 MeV in 'adding-back' mode. GEANT Monte-Carlo code simulations reproduce the measured response rather well and show a very good suppression factor against neutrons (>=100) and also against cosmic rays (>=3000) for this composite spectrometer.

  17. Design of the Readout Electronics for the Qualification Model of DAMPE BGO Calorimeter

    CERN Document Server

    Feng, Changqing; Zhang, Junbin; Gao, Shanshan; Yang, Di; Zhang, Yunlong; Liu, Shubin; An, Qi

    2014-01-01

    The DAMPE (DArk Matter Particle Explorer) is a scientific satellite being developed in China, aimed at cosmic ray study, gamma ray astronomy, and searching for the clue of dark matter particles, with a planned mission period of more than 3 years and an orbit altitude of about 500 km. The BGO Calorimeter, which consists of 308 BGO (Bismuth Germanate Oxid) crystal bars, 616 PMTs (photomultiplier tubes) and 1848 dynode signals, has approximately 32 radiation lengths. It is a crucial sub-detector of the DAMPE payload, with the functions of precisely measuring the energy of cosmic particles from 5 GeV to 10TeV, distinguishing positrons/electrons and gamma rays from hadron background, and providing trigger information for the whole DAMPE payload. The dynamic range for a single BGO crystal is about 2?105 and there are 1848 detector signals in total. To build such an instrument in space, the major design challenges for the readout electronics come from the large dynamic range, the high integrity inside the very compa...

  18. A Study on Thermal Design of the BGO Electromagnetic Calorimeter

    Science.gov (United States)

    Chen, Dengyi; Hu, Yiming; Wu, Jian; Feng, Changqing; Zhang, Yunlong; Chang, Jin

    The BGO Electromagnetic Calorimeter (BGO ECAL) is one of the most important payload of the Chinese DArk Matter Particle Explorer (DAMPE), which can precisely measure the incident energy of cosmic ray. However, thermal control of the BGO ECAL plays a key role on its running in the space. In this paper, the thermal design of the BGO ECAL and the thermal FEM modal created by hyper-mesh & NASTRAN FEM software will be introduced. Then the temperature distribution of the BGO calorimeter with the given on orbit conditions is performed. In the end, we depicts the thermal test which has been carried out in February. By the comparisons between the experiment results and the analyses results, the methodology in this paper was proved to be effective.

  19. Characterization of Photon-Counting Detector Responsivity for Non-Linear Two-Photon Absorption Process

    Science.gov (United States)

    Sburlan, S. E.; Farr, W. H.

    2011-01-01

    Sub-band absorption at 1550 nm has been demonstrated and characterized on silicon Geiger mode detectors which normally would be expected to have no response at this wavelength. We compare responsivity measurements to singlephoton absorption for wavelengths slightly above the bandgap wavelength of silicon (approx. 1100 microns). One application for this low efficiency sub-band absorption is in deep space optical communication systems where it is desirable to track a 1030 nm uplink beacon on the same flight terminal detector array that monitors a 1550 nm downlink signal for pointingcontrol. The currently observed absorption at 1550 nm provides 60-70 dB of isolation compared to the response at 1064 nm, which is desirable to avoid saturation of the detector by scattered light from the downlink laser.

  20. Characterization of Photon-Counting Detector Responsivity for Non-Linear Two-Photon Absorption Process

    Science.gov (United States)

    Sburlan, S. E.; Farr, W. H.

    2011-01-01

    Sub-band absorption at 1550 nm has been demonstrated and characterized on silicon Geiger mode detectors which normally would be expected to have no response at this wavelength. We compare responsivity measurements to singlephoton absorption for wavelengths slightly above the bandgap wavelength of silicon (approx. 1100 microns). One application for this low efficiency sub-band absorption is in deep space optical communication systems where it is desirable to track a 1030 nm uplink beacon on the same flight terminal detector array that monitors a 1550 nm downlink signal for pointingcontrol. The currently observed absorption at 1550 nm provides 60-70 dB of isolation compared to the response at 1064 nm, which is desirable to avoid saturation of the detector by scattered light from the downlink laser.

  1. Simulation study of BGO array for characteristic gamma rays from neutron-stimulated elements

    Institute of Scientific and Technical Information of China (English)

    TANG Shibiao; MA Qingli; YIN Zejie; HUANG Huan

    2007-01-01

    Characteristic gamma rays of 100 keV to about 6 MeV from different elements stimulated by neurons have been applied to diagnosis biological imaging.In this paper.BGO detectors are used for the spectrum simulation.Signals from a single crystal and after correction are both obtained.and the energy spectrum summing adjacent signals seems possible to achieve excellent energy resolution for such high-energy photons.Some ideal suppositions are introduced and some other information,such as spatial resolution and difficult electronics,should be considered after this correction.

  2. Efficiency Calibration Measurement And Geant Simulation Of The Dragon Bgo Gamma Ray Array At Triumf

    CERN Document Server

    Gigliotti, D G

    2005-01-01

    A gamma ray array to detect the characteristic gammas emitted from astrophysically significant, radiative proton and alpha capture reactions, was built as part of the Detector of Recoils And Gammas Of Nuclear reactions (DRAGON) spectrometer at ISAC/TRIUMF. The DRAGON array consists of a collection of 30 hexagonal BGO detectors measuring 7.62 cm long by 5.58 cm across the face. A simulation was built with the particle-tracking program GEANT v3.21. The efficiency of the array was measured using calibrated sources of various gamma energies and compared to simulated results. For the cases where the activity of the source was not well known the sources were calibrated using a standard NaI detector of known efficiency. The agreement between simulation and measured differences is more than adequate for proposed DRAGON experiments. The analysis and results of the comparison between measured and simulated efficiency will be discussed in this thesis.

  3. Performance of a BGO-NaI {eta} spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Leitch, M.J. [Los Alamos National Lab., NM (United States). Div. of Physics; Anderson, M.E. [Los Alamos National Lab., NM (United States). Div. of Physics; Kapustinsky, J. [Los Alamos National Lab., NM (United States). Div. of Physics; Li, T.K. [Los Alamos National Lab., NM (United States). Div. of Physics; Mishra, C.S. [Los Alamos National Lab., NM (United States). Div. of Physics; Peng, J.C. [Los Alamos National Lab., NM (United States). Div. of Physics; Simmons, J.E. [Los Alamos National Lab., NM (United States). Div. of Physics; Dytman, S.A. [Pittsburgh Univ., PA (United States). Dept. of Physics; Hardie, J.G. [Pittsburgh Univ., PA (United States). Dept. of Physics; Von Reden, K.F. [Pittsburgh Univ., PA (United States). Dept. of Physics; Smith, C. [University of Virginia, Charlottesville, VA 22901 (United States)

    1996-06-01

    A two-arm spectrometer, designed to detect {eta} and {pi}{sup 0} mesons, has been built and used in ({pi},{eta}) measurements at LAMPF. This spectrometer contains BGO active converters and NaI total-energy counters. Its construction and performance for ({pi}{sup -},{pi}{sup 0}) and ({pi}{sup -},{eta}) measurements on CH{sub 2} are described. Novel techniques to monitor the gains of the BGO and NaI counters are also presented. (orig.).

  4. Circularly polarized photons at the BGO-OD experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, Thomas [Physikalisches Institut, Universitaet Bonn (Germany); Collaboration: BGO-OD-Collaboration

    2015-07-01

    The BGO-OD experiment, presently starting data taking at the electron accelerator ELSA at the University of Bonn, is intended for the systematic investigation of the photo-production of mesons and the structure and dynamics of nucleon excitations. To disentangle the different contributions to the measured observables, linearly and circularly polarized photons are used. This talk describes the production of circularly polarized photons at the BGO-OD experiment and how the degree of polarization is determined using a Moeller polarimeter. First results using circular polarization are presented.

  5. Single-step absorption and phase retrieval with polychromatic x rays using a spectral detector.

    Science.gov (United States)

    Gürsoy, Doğa; Das, Mini

    2013-05-01

    In this Letter, we present a single-step method to simultaneously retrieve x-ray absorption and phase images valid for a broad range of imaging energies and material properties. Our method relies on the availability of spectrally resolved intensity measurements, which is now possible using semiconductor x-ray photon counting detectors. The retrieval method is derived and presented, with results showing good agreement.

  6. Influence of radiation damage on BGO scintillation properties

    Energy Technology Data Exchange (ETDEWEB)

    Georgii, R.; Meissl, R.; Lichti, G.G.; Schoenfelder, V. [Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany); Hajdas, W. [Paul-Scherrer Institut, CH-5232 Villigen (Switzerland); Henschel, H. [Fraunhofer-Institut fuer Naturwissenschaftlich-Technische Trendanalyse, D-53879 Euskirchen (Germany); Graef, H.-D.; Neumann-Cosel, P. von; Richter, A. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany)

    1998-08-11

    Aboard INTEGRAL, the next medium-size {gamma}-ray mission of the European Space Agency (ESA), a high-resolution Ge-spectrometer array with a BGO anticoincidence shield and imaging capability will be flown. The influence of the radiation damage on the photoelectron yield of the BGO scintillators due to the radiation environment in the orbit, i.e. {gamma}-rays, electrons and protons from the radiation, belts and the cosmic diffuse radiation, was investigated. Irradiation tests with doses equivalent to the orbit conditions were performed and the photoelectron yields of different BGO crystals were measured. It was found that for equal doses the reduction of the photoelectron yield varies strongly for the crystals of different manufacturers. Furthermore, electromagnetic radiation affects the photoelectron yield much stronger than particle radiation. A possible explanation is given by interpreting the effect due to {gamma}-rays primarily as damage of the electronic structure of the BGO, whereas the particle radiation damages mainly the crystal structure. (orig.) 19 refs.

  7. Plasmonic structure integrated single-photon detector configurations to improve absorptance and polarization contrast

    CERN Document Server

    Csete, Maria; Szenes, Andras; Szalai, Aniko; Szabo, Gabor

    2014-01-01

    Configurations capable of maximizing both absorptance and polarization contrast were determined for 1550 nm polarized light illumination of different plasmonic structure integrated superconducting nanowire single-photon detectors (SNSPDs) consisting of p=264 nm and P=792 nm periodic niobium-nitride (NbN) patterns on silica substrate. Global NbN absorptance maxima appear in case of p/s-polarized light illumination in S/P-orientation (gamma=90 azimuthal angle) and the highest polarization contrast is attained in S-orientation of all devices. Common nanophotonical origin of absorptance enhancement is collective resonance on nano-cavity-gratings with different profiles, which is promoted by coupling between localized modes in quarter wavelength MIM nano-cavities and laterally synchronized Brewster-Zenneck-type surface waves in integrated SNSPDs possessing a three-quarter-wavelength-scaled periodicity. The spectral sensitivity and dispersion characteristics reveal that device design specific optimal configurations...

  8. Analytic model of energy-absorption response functions in compound X-ray detector materials.

    Science.gov (United States)

    Yun, Seungman; Kim, Ho Kyung; Youn, Hanbean; Tanguay, Jesse; Cunningham, Ian A

    2013-10-01

    The absorbed energy distribution (AED) in X-ray imaging detectors is an important factor that affects both energy resolution and image quality through the Swank factor and detective quantum efficiency. In the diagnostic energy range (20-140 keV), escape of characteristic photons following photoelectric absorption and Compton scatter photons are primary sources of absorbed-energy dispersion in X-ray detectors. In this paper, we describe the development of an analytic model of the AED in compound X-ray detector materials, based on the cascaded-systems approach, that includes the effects of escape and reabsorption of characteristic and Compton-scatter photons. We derive analytic expressions for both semi-infinite slab and pixel geometries and validate our approach by Monte Carlo simulations. The analytic model provides the energy-dependent X-ray response function of arbitrary compound materials without time-consuming Monte Carlo simulations. We believe this model will be useful for correcting spectral distortion artifacts commonly observed in photon-counting applications and optimal design and development of novel X-ray detectors.

  9. A Study of Multiple Scattering in BGO and LYSO Single Crystal Scintillators

    Directory of Open Access Journals (Sweden)

    Kittipong Seingsanoh

    2016-08-01

    Full Text Available The angular distribution of multiple Compton scatterings from BGO and LYSO single crystal scintillators was studied at various scattering angles. Gamma photons with 662 keV energy, acquired from a 137Cs source, were used. The scattered photons were detected by a 51mm × 51mm NaI(Tl scintillation detector. The overall energy correlated to the total number of scattered incidents was analytically reconstructed. The research found that the multiply scattered incidents had the same energy as received from the singly scattered distribution, as the attribution of multiply scattered incidents near the 90° scattering angle revealed. The research results were in agreement with the theoretical calculations.

  10. Energy correction for the BGO calorimeter of DAMPE using an electron beam

    Science.gov (United States)

    Li, Zhi-Ying; Zhang, Zhi-Yong; Wei, Yi-Feng; Wang, Chi; Zhang, Yun-Long; Wen, Si-Cheng; Wang, Xiao-Lian; Xu, Zi-Zong; Huang, Guang-Shun

    2016-08-01

    The DArk Matter Particle Explorer is an orbital indirect dark matter search experiment which measures the spectra of photons, electrons and positrons originating from deep space. The electromagnetic calorimeter (ECAL), made of bismuth germinate (BGO), is one of the key sub-detectors of DAMPE, and is designed for energy measurement with a large dynamic range from 5 GeV to 10 TeV. In this paper, methods for energy correction are discussed, in order to reconstruct the primary energy of the incident electrons. Different methods are chosen for the appropriate energy ranges. The correction results of Geant4 simulation and beam test data (at CERN) are presented. Supported by the Chinese 973 Program (2010CB833002), the Strategic Priority Research Program on Space Science of the Chinese Academy of Science (XDA04040202-4) and 100 Talents Program of CAS

  11. Calibration of BGO Calorimeter of the DAMPE in Space

    Science.gov (United States)

    Wang, Chi

    2016-07-01

    The Dark Matter Particle Explore (DAMPE) is a satellite based experiment which launched on December 2015 and aims at indirect searching for dark matter by measuring the spectra of high energy e±, γ from 5GeV up to 10TeV originating from deep space. The 3D imaging BGO calorimeter of DAMPE was designed to precisely measurement the primary energy of the electromagnetic particle and provides a highly efficient rejection of the hadronic background by reconstruct the longitudinal and lateral profiles of showers. To achieve the expected accuracy on the energy measurement, each signal channel has to be calibrated. The energy equalization is performed using the signal that Minimum Ionizing Particles (MIP) leave in each BGO bar, the MIPs measurement method with orbit data and, data quality, time stability using MIPs data will be presented, too.

  12. Improvement of infrared single-photon detectors absorptance by integrated plasmonic structures

    CERN Document Server

    Csete, M; Szalai, A; Najafi, F; Berggren, K K

    2012-01-01

    The absorptance of p-polarized light in superconducting-nanowire single-photon detectors (SNSPDs) was improved by integrating (1) ~quarter-wavelength nano-optical cavity closed by a gold reflector (OC-SNSPD), (2) nano-cavity-array closed by vertical and horizontal gold segments (NCAI-SNSPD), and (3) nano-cavity-deflector-array consisting of longer vertical gold segments (NCDAI-SNSPD) into short- (p-) and long- (3p-) periodic niobium-nitride (NbN) stripe-patterns. In OC-SNSPDs the highest absorptance is observable at perpendicular incidence onto NbN stripes in P-orientation due to E-field concentration at the bottom of nano-optical cavities. In short-periodic NCAI-SNSPDs off-axis illumination results in almost polar-angle-independent perfect absorptance due to collective resonances on plasmonic MIM nano-cavity-arrays in S-orientation. In long-periodic NCAI-SNSPDs the surface wave-excitation phenomena promoting EM-field transportation to the NbN stripes in S-orientation are capable of resulting in local absorpt...

  13. Plasmonic Structure Integrated Single-Photon Detector Configurations to Improve Absorptance and Polarization Contrast

    Directory of Open Access Journals (Sweden)

    Mária Csete

    2015-02-01

    Full Text Available Configurations capable of maximizing both the absorption component of system detection efficiency and the achievable polarization contrast were determined for 1550 nm polarized light illumination of different plasmonic structure integrated superconducting nanowire single-photon detectors (SNSPDs consisting of p = 264 nm and P = 792 nm periodic niobium nitride (NbN patterns on silica substrate. Global effective NbN absorptance maxima appear in case of p/s-polarized light illumination in S/P-orientation (γ = 90°/0° azimuthal angle and the highest polarization contrast is attained in S-orientation of all devices. Common nanophotonical origin of absorptance enhancement is collective resonance on nanocavity gratings with different profiles, which is promoted by coupling between localized modes in quarter-wavelength metal-insulator-metal nanocavities and laterally synchronized Brewster-Zenneck-type surface waves in integrated SNSPDs possessing a three-quarter-wavelength-scaled periodicity. The spectral sensitivity and dispersion characteristics reveal that device design specific optimal configurations exist.

  14. Onboard calibration circuit for the DAMPE BGO calorimeter front-end electronics

    Science.gov (United States)

    Zhang, De-Liang; Feng, Chang-Qing; Zhang, Jun-Bin; Wang, Qi; Ma, Si-Yuan; Shen, Zhong-Tao; Jiang, Di; Gao, Shan-Shan; Zhang, Yun-Long; Guo, Jian-Hua; Liu, Shu-Bin; An, Qi

    2016-05-01

    DAMPE (DArk Matter Particle Explorer) is a scientific satellite which is mainly aimed at indirectly searching for dark matter in space. One critical sub-detector of the DAMPE payload is the BGO (bismuth germanium oxide) calorimeter, which contains 1848 PMT (photomultiplier tube) dynodes and 16 FEE (Front-End Electronics) boards. VA160 and VATA160, two 32-channel low power ASICs (Application Specific Integrated Circuits), are adopted as the key components on the FEEs to perform charge measurement for the PMT signals. In order to monitor the parameter drift which may be caused by temperature variation, aging, or other environmental factors, an onboard calibration circuit is designed for the VA160 and VATA160 ASICs. It is mainly composed of a 12-bit DAC (Digital to Analog Converter), an operational amplifier and an analog switch. Test results showed that a dynamic range of 0-30 pC with a precision of 5 fC (Root Meam Square, RMS) was achieved, which covers the VA160’s input range. It can be used to compensate for the temperature drift and test the trigger function of the FEEs. The calibration circuit has been implemented for the front-end electronics of the BGO Calorimeter and verified by all the environmental tests for both Qualification Model and Flight Model of DAMPE. The DAMPE satellite was launched at the end of 2015 and the calibration circuit will operate periodically in space. Supported by Strategic Priority Research Program on Space Science of Chinese Academy of Sciences (XDA04040202-4), and National Basic Research Program (973 Program) of China (2010CB833002) and National Natural Science Foundation of China (11273070)

  15. Linearly polarised photons at the BGO-OD experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bella, Andreas [Physikalisches Institut, Universitaet Bonn (Germany); Collaboration: BGO-OD-Collaboration

    2015-07-01

    The BGO-OD experiment, located at the ELSA accelerator of the University of Bonn, aims at the study of photoproduction reactions off the nucleon. A real, energy-tagged photon beam is produced via bremsstrahlung by irradiating a thin radiator with the electron beam provided by ELSA. Linear polarisation is obtained by coherent bremsstrahlung. This requires a crystal radiator; in our case a 570 μm thick diamond is used. The production mechanism of a linearly polarised photon beam via coherent bremsstrahlung, the determination of the degree of polarisation and first results obtained with a linearly polarised photon beam are shown in this talk.

  16. Status of the Argonne-Notre Dame BGO gamma-ray facility at ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, R.V.; Blumenthal, D.J.; Carpenter, M.P. [and others

    1995-08-01

    The gamma-ray facility at ATLAS consists of (a) a 4{pi} gamma-sum/multiplicity spectrometer with 50 BGO hexagonal elements (inner array) and (b) 12 Compton-suppressed germanium detectors (CSG) external to the inner array. During the past year the effort related to this facility continued on several fronts. Because of neutron damage, annealing was performed on eight Ge detectors. Three of these were annealed twice. The performance of the detectors was recovered in all but one case. In the latter, the FET was lost and the detector was returned to the manufacturer for repair. Maintenance and repairs had to be performed on several electronics modules and, in particular, on some of the CAMAC units. None of these problems affected an experiment for more than a couple of hours. Preventive maintenance was performed on the LN{sub 2} filling system (inspection of all filling lines and check of the various functions of the control modules). 10 of the CSGs were moved to the FMA for long periods of time on three different occasions and were used in conjunction with this device. Such a move takes about 1 day, does not require that the Ge detectors be warmed up, and has not resulted in any noticeable loss in performance of the CSGs. A new dedicated target chamber was designed and constructed. This chamber allows us to place a target upstream from the usual location, outside of the array. In this way it is possible to study decays from isomers after recoil from the target into a stopper located at the focus of the {gamma}-ray facility.

  17. Radiation resistivity of BGO crystals due to low-energy gamma-rays

    CERN Document Server

    Kozma, P

    2003-01-01

    Radiation resistivity of 4x4x30 mm sup 3 BGO crystals from three suppliers has been studied for doses 10 sup 4 Gy (10 sup 6 rad) and 10 sup 5 Gy (10 sup 7 rad). Radiation hardness was examined by the measurement of optical transmission through BGO crystals before and after sup 6 sup 0 Co gamma-ray irradiations. The absolute degradation of transmission for 10 sup 4 and 10 sup 5 Gy doses at 480 nm wavelength of the peak emission of BGO, was found to be lower than 3.4% and 7.5%, respectively. The results have been also compared with radiation hardness measurements for a large volume diameter 30x30 mm sup 3 BGO crystal as well as another heavy scintillation crystals: fluorides and tungstates. Complete recovery of BGO radiation damage was observed only after few days.

  18. Raman Spectrum Analysis on the Solid-Liquid Boundary Layer of BGO Crystal Growth

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xia; YIN Shao-Tang; WAN Song-Ming; YOU Jing-Lin; CHEN Hui; ZHAO Si-Jie; ZHANG Qing-Li

    2007-01-01

    We study the Raman spectra of Bi4Ge3O12 crystal at different temperatures, as well as its melt. The structure characters of the single crystal, melt and growth solid-liquid boundary layer of BGO are investigated by their high-temperature Raman spectra for the first time. The rule of structure change of BGO crystal with increasing temperature is analysed. The results show that there exists [GeO4] polyhedral structure and Bi ion independently in BGO melt. The bridge bonds Bi-O-Bi and Bi-O-Ge appear in the crystal and at the boundary layer, but disappear in the melt. The structure of the growth solid-liquid boundary layer is similar to that of BGO crystal. In the melt, the long-range order structure of the crystal disappears. The thickness of the grovth solid-liquid boundary layer of BGO crystal is about 50 μm.

  19. Integrated fiber optic incoherent broadband cavity enhanced absorption spectroscopy detector for near-IR absorption measurements of nanoliter samples.

    Science.gov (United States)

    Gomez, Anthony L; Renzi, Ronald F; Fruetel, Julia A; Bambha, Ray P

    2012-05-10

    An integrated fiber-optic sensor is described that uses incoherent broadband cavity enhanced absorption spectroscopy for sensitive detection of aqueous samples in nanoliter volumes. Absorption was measured in a 100 µm gap between the ends of two short segments of multimode graded-index fiber that were integrated into a capillary using a precision machined V-grooved fixture that allowed for passive fiber alignment. The other ends of the fibers were coated with dielectric mirrors to form a 9.5 cm optical resonator. Light from a fiber-coupled superluminescent diode was directly coupled into one end of the cavity, and transmission was measured using a fiber-coupled silicon photodiode. Dilute aqueous solutions of near infrared dye were used to determine the minimum detectable absorption change of 2.4×10(-4) under experimental conditions in which pressure fluctuations limited performance. We also determined that the absolute minimum detectable absorption change would be 1.6×10(-5) for conditions of constant pressure in which absorption measurement is limited by electronic and optical noise. Tolerance requirements for alignment are also presented.

  20. Short-wave infrared barriode detectors using InGaAsSb absorption material lattice matched to GaSb

    Energy Technology Data Exchange (ETDEWEB)

    Craig, A. P.; Percy, B.; Marshall, A. R. J. [Physics Department, Lancaster University, Lancaster LA1 4YB (United Kingdom); Jain, M. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Wicks, G.; Hossain, K. [Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); Golding, T. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); McEwan, K.; Howle, C. [Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ (United Kingdom)

    2015-05-18

    Short-wave infrared barriode detectors were grown by molecular beam epitaxy. An absorption layer composition of In{sub 0.28}Ga{sub 0.72}As{sub 0.25}Sb{sub 0.75} allowed for lattice matching to GaSb and cut-off wavelengths of 2.9 μm at 250 K and 3.0 μm at room temperature. Arrhenius plots of the dark current density showed diffusion limited dark currents approaching those expected for optimized HgCdTe-based detectors. Specific detectivity figures of around 7×10{sup 10} Jones and 1×10{sup 10} Jones were calculated, for 240 K and room temperature, respectively. Significantly, these devices could support focal plane arrays working at higher operating temperatures.

  1. X-ray absorption spectroscopy of diluted system by undulator photon source and multi-element solid-state detector

    CERN Document Server

    Tanida, H

    2001-01-01

    In order to measure the extended X-ray absorption fine structure (EXAFS) spectrum of an ultra-diluted system, an optics and detector control system for a synchrotron radiation beamline is developed. The undulator gap width is continuously tuned to obtain the maximum X-ray photon flux during the energy scan for the EXAFS measurement. A piezoelectric translator optimizes the parallelism of the double crystal in a monochromator at each measurement point to compensate for mechanical errors of the monochromator, resulting in a smooth and intense X-ray photon flux during the measurement. For a detection of a weak fluorescence signal from diluted samples, a 19-element solid-state detector and digital signal processor are used. A K-edge EXAFS spectrum of iron in a myoglobin aqueous solution with a concentration of 5.58 parts per million was obtained by this system.

  2. Economical and Efficient Detector for Fluorescent X-Ray Absorption Spectroscopy

    Science.gov (United States)

    Khalid, S. M.; Rosenbaum, G.; Chance, B.

    1986-08-01

    The available synchrotron radiation sources and those proposed for construction in the near future in the US and abroad can produce fluxes of x-radiation high enough that the fluorescent and scattered flux even from biological samples approach and will exceed acceptable levels of counting losses even in fast photon counting detector system. Ionization chambers in current integration mode can afford very high flux and large apertures. But they suffer time limitations in the fraction of the millisecond region, microphonics, and the necessity of a gas supply of very constant pressure. We have developed an alternative detector system consisting of a photomultiplier tube equipped with a highly efficient ZnS (Ag) scintillator in current integration mode. It can have apertures up to 5 inches in diameter and a time resolution adequate for rapid reaction studies using synchrontron radiation (70 ns decay time to 10%). In initial tests, we did not detect any saturation effects with the fluxes available. The advantages of these detectors seem to be simplicity and reliability in addition to freedom from environmental effects and the relatively low cost compared to other devices. These detectors have been used successfully at the Photon Factory, Japan and at CHESS.

  3. Environmental test of the BGO calorimeter for DArk Matter Particle Explorer

    Science.gov (United States)

    Hu, Yi-Ming; Chang, Jin; Chen, Deng-Yi; Guo, Jian-Hua; Zhang, Yun-Long; Feng, Chang-Qing

    2016-11-01

    DArk Matter Particle Explorer (DAMPE) is the first Chinese astronomical satellite, successfully launched on Dec. 17 2015. As the most important payload of DAMPE, the BGO calorimeter contains 308 bismuth germanate crystals, with 616 photomultiplier tubes, one coupled to each end of every crystal. Environmental tests have been carried out to explore the environmental adaptability of the flight model of the BGO calorimeter. In this work we report the results of the vibration tests. During the vibration tests, no visible damage occurred in the mechanical assembly. After random or sinusoidal vibrations, the change of the first order natural frequency of BGO calorimeter during the modal surveys is less than 5%. The shift ratio of Most Probable Value of MIPs changes in cosmic-ray tests are shown, the mean value of which is about -4%. The comparison of results of cosmic-ray tests before and after the vibration shows no significant change in the performance of the BGO calorimeter. All these results suggest that the calorimeter and its structure have passed through the environment tests successfully. Supported by National Natural Science Foundation of China (11203090, 11003051, 11273070) and Strategic Priority Research Program on Space Science of Chinese Academy of Sciences (XDA04040202)

  4. BGO front-end electronics and signal processing in the MXGS instrument for the ASIM mission

    DEFF Research Database (Denmark)

    Skogseide, Yngve; Cenkeramaddi, Linga Reddy; Genov, Georgi

    2012-01-01

    This paper presents the Bismuth Germanate Oxide (BGO) front-end electronics design and signal processing in Modular X- and Gamma ray sensor (MXGS) instrument onboard the Atmosphere Space Interaction Monitor (ASIM) mission, funded by the European Space Agency. University of Bergen is responsible...

  5. Properties of BGO thin films under the influence of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Arshak, K. [Electronic and Computer Engineering Department, University of Limerick, Limerick (Ireland)], E-mail: khalil.arshak@ul.ie; Korostynska, O.; Harris, J. [Electronic and Computer Engineering Department, University of Limerick, Limerick (Ireland); Morris, D.; Arshak, A. [Physics Department, University of Limerick, Limerick (Ireland); Jafer, E. [Electronic and Computer Engineering Department, University of Limerick, Limerick (Ireland)

    2008-02-15

    It is important to know the behaviour of materials under the influence of radiation for the effective design of novel sensor systems. Optical properties of bismuth germinate (Bi{sub 4}Ge{sub 3}O{sub 12}-BGO) thin films were investigated in terms of their perception to gamma radiation exposure. An Edwards E306A vacuum thermal coating system was used for thin films deposition. BGO films with a thickness of 200 nm were exposed to a disk-type {sup 137}Cs gamma radiation source with an activity of 370 kBq. Optical properties of the films were investigated using CARY IE UV-Visible Spectrophotometer. Calculated optical band gap for as-deposited BGO thin film was 1.95 eV. Gamma radiation induced changes in the optical properties of thin films, which could be explained by the variation in the degree of disorder. From the density-of-state model, it is known that optical band gap decreases with an increasing degree of disorder of the amorphous phase. Electrical properties of BGO thin films were recorded in real time using a low power capacitive interface system with a high resolution, which is based on Delta-sigma modulator. At doses from 0 to 1.5 mGy little if any changes in the capacitance were measured. This could be explained by co-existence of two processes, namely creation and annihilation of defects under the influence of radiation. After a threshold dose of 1.5 mGy creation of defects becomes more prevailing and the BGO film capacitance has gradually increased in value from 2.97 pF to 7.09 pF after irradiation with a 2.44 mGy dose.

  6. Formation of slab waveguides in eulytine type BGO and CaF{sub 2} crystals by implantation of MeV nitrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Banyasz, I., E-mail: bakonyjako@yahoo.es [Department of Crystal Physics, Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Berneschi, S. [Centro Studi e Ricerche ' Enrico Fermi' , Piazza del Viminale 2, 00184 Roma (Italy); MDF-Lab, ' ' Nello Carrara' ' Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Khanh, N.Q.; Lohner, T. [Research Institute for Technical Physics and Materials Science of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Lengyel, K. [Department of Crystal Physics, Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Fried, M. [Research Institute for Technical Physics and Materials Science of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Peter, A. [Department of Crystal Physics, Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Petrik, P.; Zolnai, Z. [Research Institute for Technical Physics and Materials Science of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Watterich, A. [Department of Crystal Physics, Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Nunzi-Conti, G.; Pelli, S.; Righini, G.C. [MDF-Lab, ' ' Nello Carrara' ' Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)

    2012-09-01

    Ion implantation, compared with other waveguide fabrication methods, has some unique advantages. It has proved to be a universal technique for producing waveguides in most optical materials. The authors of the present article reported fabrication of channel and slab waveguides in an Erbium-doped tungsten tellurite glass by implantation of MeV energy N{sup +} ions. The present article reports successful adaptation of the same technique to the fabrication of slab waveguides in eulytine type bismuth germanate (BGO) and CaF{sub 2} crystals. This is the first report on successful waveguide fabrication in these materials using 3.5 MeV N{sup +} ions at implanted fluences between 5 Multiplication-Sign 10{sup 15} and 4 Multiplication-Sign 10{sup 16} ions/cm{sup 2}. Spectroscopic ellipsometric measurements revealed the existence of guiding structures in both materials. M-line spectroscopic measurements indicated guiding effect in the as-implanted BGO up to 1550 nm and up to 980 nm in the as-implanted CaF{sub 2}. Ion implantation induced the appearance of three peaks in the UV/Vis absorption spectrum of CaF{sub 2}, that can be attributed to colour centres.

  7. Single Event Effect Hardness for the Front-end ASICs Applied in BGO Calorimeter of DAMPE Satellite

    CERN Document Server

    Gao, Shan-Shan; Feng, Chang-Qing; Xi, Kai; Liu, Shu-Bin; An, Qi

    2016-01-01

    Dark Matter Particle Explorer (DAMPE) is a Chinese scientific satellite designed for cosmic ray study with a primary scientific goal of indirect search of dark matter particles. As a crucial sub-detector, BGO calorimeter measures the energy spectrum of cosmic rays in the energy range from 5 GeV to 10 TeV. In order to implement high-density front-end electronics (FEE) with the ability to measure 1848 signals from 616 photomultiplier tubes on the strictly constrained satellite platform, two kinds of 32-channel front-end ASICs, VA160 and VATA160, are customized. However, a space mission period of more than 3 years makes single event effect (SEE) a probable threat to reliability. In order to evaluate the SEE sensitivity of the chips and verify the effectiveness of mitigation methods, a series of laser-induced and heavy ion-induced SEE tests were performed. Benefiting from the single event latch-up (SEL) protection circuit for power supply, the triple module redundancy (TMR) technology for the configuration regist...

  8. Proof of principle of a high-spatial-resolution, resonant-response gamma-ray detector for Gamma Resonance Absorption in 14N

    CERN Document Server

    Brandis, M; Vartsky, D; Friedman, E; Kreslo, I; Mardor, I; Dangendorf, V; Levi, S; Mor, I; Bar, D

    2011-01-01

    The development of a mm-spatial-resolution, resonant-response detector based on a micrometric glass capillary array filled with liquid scintillator is described. This detector was developed for Gamma Resonance Absorption (GRA) in 14N. GRA is an automatic-decision radiographic screening technique that combines high radiation penetration (the probe is a 9.17 MeV gamma ray) with very good sensitivity and specificity to nitrogenous explosives. Detailed simulation of the detector response to electrons and protons generated by the 9.17 MeV gamma-rays was followed by a proof-of-principle experiment, using a mixed gamma-ray and neutron source. Towards this, a prototype capillary detector was assembled, including the associated filling and readout systems. Simulations and experimental results indeed show that proton tracks are distinguishable from electron tracks at relevant energies, on the basis of a criterion that combines track length and light intensity per unit length.

  9. Proof of principle of a high-spatial-resolution, resonant-response γ-ray detector for Gamma Resonance Absorption in 14N

    Science.gov (United States)

    Brandis, M.; Goldberg, M. B.; Vartsky, D.; Friedman, E.; Kreslo, I.; Mardor, I.; Dangendorf, V.; Levi, S.; Mor, I.; Bar, D.

    2011-02-01

    The development of a mm-spatial-resolution, resonant-response detector based on a micrometric glass capillary array filled with liquid scintillator is described. This detector was developed for Gamma Resonance Absorption (GRA) in 14N. GRA is an automatic-decision radiographic screening technique that combines high radiation penetration (the probe is a 9.17 MeV γ-ray) with very good sensitivity and specificity to nitrogenous explosives. Detailed simulation of the detector response to electrons and protons generated by the 9.17 MeV γ-rays was followed by a proof-of-principle experiment, using a mixed γ-ray and neutron source. Towards this, a prototype capillary detector was assembled, including the associated filling and readout systems. Simulations and experimental results indeed show that proton tracks are distinguishable from electron tracks at relevant energies, based on a criterion that combines track length and light intensity per unit length.

  10. Research of Spectrometric and Exploitation Characteristics of BGO-PMP-165 Scintiblock in Temperature Interval from +25 to -140$^{o}$C

    CERN Document Server

    Ainbund, M R; Gundorin, N A; Matveev, D V; Serov, D G

    2001-01-01

    Photomultipliers based on microchannel plates are used for fast systems which form time marks of physical setups as well as in special technical areas. It is not uncommon when they substitute traditional dynode system photomultipliers. The possibility of compatible work of the PMP-165 photomultiplier with BGO crystal which were cooled down to temperature necessary for appropriate functioning of a semiconductor Ge detector with taking into account of temperature dependencies of own PMP characteristics is investigated during experiment. Cooling down of the system from room temperature down to v140^{o}C during 8 hours is done. Lower limit of temperature which allows PMP to function properly is registered. Changes of spectrometric characteristics caused by temperature are studied.

  11. Calibration of the L3 BGO calorimeter using an RFQ accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Chaturvedi, U.; Favara, A. E-mail: alvise.favara@cern.ch; Gataullin, M.; Gratta, G.; Kirkby, D.; Lu, W.; Newman, H.; Shvorob, A.; Tully, C.; Zhu, R

    2001-04-01

    An improved calibration technique based on a radio-frequency-quadrupole (RFQ) accelerator is presented. A high-intensity flux of 17.6 MeV photons, produced by radiative capture of 1.85 MeV protons from the RFQ in a lithium target, is used to calibrate in situ 11,000 crystals of the L3 BGO calorimeter. We present results obtained for the calibration of 1997-1999 L3 data samples. For the first time a calibration precision better than 0.5% is reached for the entire BGO calorimeter. The importance of such a technique is also outlined in view of extensive use of crystal calorimetry at the LHC.

  12. Testing and assessment of large BGO detector for beach monitoring of radioactive particles

    NARCIS (Netherlands)

    van der Graaf, E.R.; Rigollet, C.; Maleka, P.P.; Jones, D.G.

    2007-01-01

    The Beach Monitoring Steering Group (BMSG) was set up by UKAEA to explore whether improved systems for beach monitoring of radioactive particles are available. The BMSG commissioned the British Geological Survey (BGS) and the Nuclear Geophysics Division of the Kernfysisch Versneller Instituut (KVI/N

  13. Comparison of LSO and BGO block detectors for prompt gamma imaging in ion beam therapy

    NARCIS (Netherlands)

    Hueso-Gonzalez, F.; Biegun, A. K.; Dendooven, P.; Enghardt, W.; Fiedler, F.; Golnik, C.; Heidel, K.; Kormoll, T.; Petzoldt, J.; Roemer, K. E.; Schwengner, R.; Wagner, A.; Pausch, G.

    2015-01-01

    A major weakness of ion beam therapy is the lack of tools for verifying the particle range in clinical routine. The application of the Compton camera concept for the imaging of prompt gamma rays, a by-product of the irradiation correlated to the dose distribution, is a promising approach for range a

  14. Design of a high dynamic range photomultiplier base board for the BGO ECAL of DAMPE

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiyong; Zhang, Yunlong, E-mail: ylzhang1@mail.ustc.edu.cn; Dong, Jianing; Wen, Sicheng; Feng, Changqing; Wang, Chi; Wei, Yifeng; Wang, Xiaolian; Xu, Zizong; Liu, Shubin

    2015-04-21

    A base board for photomultiplier tube (PMT) with multi-dynode readout has been developed for the BGO electromagnetic calorimeter (ECAL) of the Dark Matter Particle Explorer (DAMPE). In order to cover a high dynamic range of energy measurements, the signals are read out from different sensitive dynodes 2, 5, and 8 (Dy2, Dy5 and Dy8). The performance of this new type of base board is studied with a light-emitting diode (LED) system and cosmic rays. A wide measuring range from 0.5 to 1.0×10{sup 5} MIPs can be achieved using the VA32 readout Application Specific Integrated Circuit (ASIC)

  15. SU-C-201-01: Investigation of the Effects of Scintillator Surface Treatment On Light Output Measurements with SiPM Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, Y; Prout, D; Chatziioannou, A [University of California, Los Angeles (UCLA) (United States)

    2015-06-15

    Purpose: To examine the effect of different scintillator surface treatments (BGO crystals) on the fraction of scintillation photons that exit the crystal and reach the photodetector (SiPM). Methods: Positron Emission Tomography is based on the detection of light that exits scintillator crystals, after annihilation photons deposit energy inside these crystals. A considerable fraction of the scintillation light gets trapped or absorbed after going through multiple internal reflections on the interfaces surrounding the crystals. BGO scintillator crystals generate considerably less scintillation light than crystals made of LSO and its variants. Therefore, it is crucial that the small amount of light produced by BGO exits towards the light detector. The surface treatment of scintillator crystals is among the factors affecting the ability of scintillation light to reach the detectors. In this study, we analyze the effect of different crystal surface treatments on the fraction of scintillation light that is detected by the solid state photodetector (SiPM), once energy is deposited inside a BGO crystal. Simulations were performed by a Monte Carlo based software named GATE, and validated by measurements from individual BGO crystals coupled to Philips digital-SiPM sensor (DPC-3200). Results: The results showed an increment in light collection of about 4 percent when only the exit face of the BGO crystal, is unpolished; compared to when all the faces are polished. However, leaving several faces unpolished caused a reduction of at least 10 percent of light output when the interaction occurs as far from the exit face of the crystal as possible compared to when it occurs very close to the exit face. Conclusion: This work demonstrates the advantages on light collection from leaving unpolished the exit face of BGO crystals. The configuration with best light output will be used to obtain flood images from BGO crystal arrays coupled to SiPM sensors.

  16. A novel surface-sensitive X-ray absorption spectroscopic detector to study the thermal decomposition of cathode materials for Li-ion batteries

    Science.gov (United States)

    Nonaka, Takamasa; Okuda, Chikaaki; Oka, Hideaki; Nishimura, Yusaku F.; Makimura, Yoshinari; Kondo, Yasuhito; Dohmae, Kazuhiko; Takeuchi, Yoji

    2016-09-01

    A surface-sensitive conversion-electron-yield X-ray absorption fine structure (CEY-XAFS) detector that operates at elevated temperatures is developed to investigate the thermal decomposition of cathode materials for Li-ion batteries. The detector enables measurements with the sample temperature controlled from room temperature up to 450 °C. The detector is applied to the LiNi0.75Co0.15Al0.05Mg0.05O2 cathode material at 0% state of charge (SOC) and 50% SOC to examine the chemical changes that occur during heating in the absence of an electrolyte. The combination of surface-sensitive CEY-XAFS and bulk-sensitive transmission-mode XAFS shows that the reduction of Ni and Co ions begins at the surface of the cathode particles at around 150 °C, and propagates inside the particle upon further heating. These changes with heating are irreversible and are more obvious at 50% SOC than at 0% SOC. The fraction of reduced Ni ions is larger than that of reduced Co ions. These results demonstrate the capability of the developed detector to obtain important information for the safe employment of this cathode material in Li-ion batteries.

  17. Modeling of normal incidence absorption in p-type GaAs/AlGaAs quantum well infrared detectors

    Science.gov (United States)

    Brown, Gail J.; Szmulowicz, Frank

    1995-04-01

    The absorption of infrared radiation at normal incidence in p-type GaAs/AlGaAs quantum wells, unlike in n-type, is fundamentally allowed. We have measured and theoretically modeled the bound-to-continuum absorption in these p-type materials. The infrared absorption coefficient was calculated are based on the electronic structure, wave functions and optical matrix elements obtained from an 8 X 8 envelope-function approximation (EFA) calculation. The 8 X 8 EFA Hamiltonian incorporates the coupling between the heavy, light, spin-orbit, and conduction bands. In calculating the continuum states for bound-to- continuum intersubband absorption, we do not enclose the well in an artificial box with infinite walls. A comparison of the theoretical absorption and measured photoresponse results verified the accuracy of our model and provided a basis for optimizing the design of p-type quantum wells for infrared detection.

  18. MCNP modelling of scintillation-detector gamma-ray spectra from natural radionuclides

    NARCIS (Netherlands)

    Hendriks, Peter; Maucec, M; de Meijer, RJ

    2002-01-01

    gamma-ray spectra of natural radionuclides are simulated for a BGO detector in a borehole geometry using the Monte Carlo code MCNP. All gamma-ray emissions of the decay of K-40 and the series of Th-232 and U-238 are used to describe the source. A procedure is proposed which excludes the time-consumi

  19. Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors

    CERN Document Server

    Scott, R H H; Perez, F; Streeter, M J V; Davies, J R; Schlenvoigt, H -P; Santos, J J; Hulin, S; Lancaster, K L; Baton, S D; Rose, S J; Norreys, P A

    2013-01-01

    A photon detector suitable for the measurement of bremsstrahlung spectra generated in relativistically-intense laser-solid interactions is described. The Monte Carlo techniques used to back-out the fast electron spectrum and laser energy absorbed into fast electrons are detailed. A relativistically-intense laser-solid experiment using frequency doubled laser light is used to demonstrate the effective operation of the detector. The experimental data was interpreted using the 3-spatial-dimension Monte Carlo code MCNPX (Pelowitz 2008), and the fast electron temperature found to be 125 keV.

  20. Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors.

    Science.gov (United States)

    Scott, R H H; Clark, E L; Pérez, F; Streeter, M J V; Davies, J R; Schlenvoigt, H-P; Santos, J J; Hulin, S; Lancaster, K L; Baton, S D; Rose, S J; Norreys, P A

    2013-08-01

    A photon detector suitable for the measurement of bremsstrahlung spectra generated in relativistically intense laser-solid interactions is described. The Monte Carlo techniques used to extract the fast electron spectrum and laser energy absorbed into forward-going fast electrons are detailed. A relativistically intense laser-solid experiment using frequency doubled laser light is used to demonstrate the effective operation of the detector. The experimental data were interpreted using the 3-spatial-dimension Monte Carlo code MCNPX [D. Pelowitz, MCNPX User's Manual Version 2.6.0, Los Alamos National Laboratory, 2008], and the fast electron temperature found to be 125 keV.

  1. Note: application of a pixel-array area detector to simultaneous single crystal X-ray diffraction and X-ray absorption spectroscopy measurements.

    Science.gov (United States)

    Sun, Cheng-Jun; Zhang, Bangmin; Brewe, Dale L; Chen, Jing-Sheng; Chow, G M; Venkatesan, T; Heald, Steve M

    2014-04-01

    X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) are two main x-ray techniques in synchrotron radiation facilities. In this Note, we present an experimental setup capable of performing simultaneous XRD and XAS measurements by the application of a pixel-array area detector. For XRD, the momentum transfer in specular diffraction was measured by scanning the X-ray energy with fixed incoming and outgoing x-ray angles. By selecting a small fixed region of the detector to collect the XRD signal, the rest of the area was available for collecting the x-ray fluorescence for XAS measurements. The simultaneous measurement of XRD and X-ray absorption near edge structure for Pr0.67Sr0.33MnO3 film was demonstrated as a proof of principle for future time-resolved pump-probe measurements. A static sample makes it easy to maintain an accurate overlap of the X-ray spot and laser pump beam.

  2. Onboard Calibration Circuit for the Front-end Electronics of DAMPE BGO Calorimeter

    CERN Document Server

    Zhang, De-Liang; Zhang, Jun-Bin; Wang, Qi; Ma, Si-Yuan; Gao, Shan-Shan; Shen, Zhong-Tao; Jiang, Di; Guo, Jian-Hua; Liu, Shu-Bin; An, Qi

    2016-01-01

    An onboard calibration circuit has been designed for the front-end electronics (FEE) of DAMPE BGO Calorimeter. It is mainly composed of a 12 bit DAC, an operation amplifier and an analog switch. Test results showed that a dynamic range of 0 ~ 30 pC with a precision of 5 fC was achieved, which meets the requirements of the front-end electronics. Furthermore, it is used to test the trigger function of the FEEs. The calibration circuit has been implemented and verified by all the environmental tests for both Qualification Model and Flight Model of DAMPE. The DAMPE satellite will be launched at the end of 2015 and the calibration circuit will perform onboard calibration in space.

  3. Optical absorption characteristics in the assessment of powder phosphor-based x-ray detectors: from nano- to micro-scale.

    Science.gov (United States)

    Liaparinos, P F

    2015-11-21

    X-ray phosphor-based detectors have enormously improved the quality of medical imaging examinations through the optimization of optical diffusion. In recent years, with the development of science and technology in the field of materials, improved powder phosphors require structural and optical properties that contribute to better optical signal propagation. The purpose of this paper was to provide a quantitative and qualitative understanding of the optical absorption characteristics in the assessment of powder phosphor-based detectors (from nano- scale up to micro-scale). Variations on the optical absorption parameters (i.e. the light extinction coefficient [Formula: see text] and the percentage probability of light absorption p%) were evaluated based on Mie calculations examining a wide range of light wavelengths, particle refractive indices and sizes. To model and assess the effects of the aforementioned parameters on optical diffusion, Monte Carlo simulation techniques were employed considering: (i) phosphors of different layer thickness, 100 μm (thin layer) and 300 μm (thick layer), respectively, (ii) light extinction coefficient values, 1, 3 and 6 μm(-1), and (iii) percentage probability of light absorption p% in the range 10(-4)-10(-2). Results showed that the [Formula: see text] coefficient is high for phosphor grains in the submicron scale and for low light wavelengths. At higher wavelengths (above 650 nm), optical quanta follow approximately similar depths until interaction for grain diameter 500 nm and 1 μm. Regarding the variability of the refractive index, high variations of the [Formula: see text] coefficient occurred above 1.6. Furthermore, results derived from Monte Carlo modeling showed that high spatial resolution phosphors can be accomplished by increasing the [Formula: see text] parameter. More specifically, the FWHM was found to decrease (i.e. higher resolution): (i) 4.8% at 100 μm and (ii) 9.5%, at 300 μm layer thickness. This study

  4. INVISIBLE ACTIVE GALACTIC NUCLEI. II. RADIO MORPHOLOGIES AND FIVE NEW H i 21 cm ABSORPTION LINE DETECTORS

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Ting; Stocke, John T.; Darling, Jeremy [Center for Astrophysics and Space Astronomy, UCB 389, University of Colorado, Boulder, CO 80309-0389 (United States); Momjian, Emmanuel [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Sharma, Soniya [Research School of Astronomy and Astrophysics, The Australian National University, Mt Stromlo Observatory, ACT 2611 (Australia); Kanekar, Nissim [National Centre for Radio Astrophysics, TIFR, Post Bag 3, Ganeshkhind, Pune 411 007 (India)

    2016-03-15

    This is the second paper directed toward finding new highly redshifted atomic and molecular absorption lines at radio frequencies. To this end, we selected a sample of 80 candidates for obscured radio-loud active galactic nuclei (AGNs) and presented their basic optical/near-infrared (NIR) properties in Paper I. In this paper, we present both high-resolution radio continuum images for all of these sources and H i 21 cm absorption spectroscopy for a few selected sources in this sample. A-configuration 4.9 and 8.5 GHz Very Large Array continuum observations find that 52 sources are compact or have substantial compact components with size <0.″5 and flux densities >0.1 Jy at 4.9 GHz. The 36 most compact sources were then observed with the Very Long Baseline Array at 1.4 GHz. One definite and 10 candidate Compact Symmetric Objects (CSOs) are newly identified, which is a detection rate of CSOs ∼three times higher than the detection rate previously found in purely flux-limited samples. Based on possessing compact components with high flux densities, 60 of these sources are good candidates for absorption-line searches. Twenty-seven sources were observed for H i 21 cm absorption at their photometric or spectroscopic redshifts with only six detections (five definite and one tentative). However, five of these were from a small subset of six CSOs with pure galaxy optical/NIR spectra (i.e., any AGN emission is obscured) and for which accurate spectroscopic redshifts place the redshifted 21 cm line in a radio frequency intereference (RFI)-free spectral “window” (i.e., the percentage of H i 21 cm absorption-line detections could be as high as ∼90% in this sample). It is likely that the presence of ubiquitous RFI and the absence of accurate spectroscopic redshifts preclude H i detections in similar sources (only 1 detection out of the remaining 22 sources observed, 13 of which have only photometric redshifts); that is, H i absorption may well be present but is masked by

  5. The effect of radiation damage on optical and scintillation properties of BGO crystals grown by the LTG Cz technique

    CERN Document Server

    Gusev, V A; Kupriyanov, I N; Kuznecov, G N; Shlegel, V N; Antsygin, V D; Vasiliev, Y V

    2002-01-01

    BGO crystals grown by the low-thermal-gradient Czochralski technique (LTG Cz) exhibit two distinct types of behavior upon radiation damage and recovery. The crystals termed as of L-type remain colorless after gamma-radiation doses as high as 10 Mrad. As the irradiation dose increases the scintillation light output shows a weak monotonous degradation to 15-25%, saturating at around several hundreds krad doses. The crystals termed as of N-type attain yellow coloration after irradiation. The light output drops abruptly for 35-50% as early as after 1 krad and does not change further on. The present work is devoted to the study of radiation damage effects, self-recovery, optically stimulated recovery and thermo-stimulated current in the L- and N-type BGO crystals produced by LTG Cz.

  6. A ground automatic testing system for the BGO calorimeter of dark matter particle explorer satellite%暗物质粒子探测卫星BGO量能器地面自动化测试软件

    Institute of Scientific and Technical Information of China (English)

    马思源; 封常青; 沈仲弢; 王奇; 刘树彬; 安琪

    2015-01-01

    Background: Bismuth Germanate (BGO) calorimeter is the key sub-detector of the Dark Matter Particle Explorer (DAMPE) satellite. There are extensive tests including the performance testing of 40 Front-end Electronics (FEE) in the engineering development model and flight model, the LED source calibration of 1600 Photomultiplier Tubes (PMT) and different kinds of ground environment simulation test as long as several months during production. Purpose: This study aims to ensure the progress of production by developing a ground test system to meet the demand for automated data collection and command parameters during the experiments and tests.Methods: First of all, the testing requirements were analyzed in details, then a framework of hardware and software was designed according to available resources. Finally the software was implemented and optimised by means of LabWindows/CVI and virtual instrument technology to fulfil all test functionalities.Results: The user interface (UI) and function modules of the software meet the requirements of data acquisition and automatic control for the BGO calorimeter of DAMPE satellite.Conclusion: This testing system has been put into practical application for more than 18 months, successfully reduced the working strength and improved the test efficiency.%锗酸铋(Bismuth Germanate, BGO)量能器是我国即将发射的暗物质粒子探测卫星的关键分系统之一.在为期数年的工程研制过程中,需开展大量测试工作,包括初样鉴定件、正样飞行件共计40块前端电子学板的性能测试,初、正样共计约1 600个光电倍增管的LED光源刻度测试,以及初、正样单机各长达数月的多项地面环境模拟试验.针对以上测试和试验过程中的自动化数据采集和指令参数配置等需求,设计开发完成了一个基于LabWindows/CVI开发平台和虚拟仪器技术的自动化测试系统,并投入实际应用,减轻了实验人员的工作强度,提高了测试效率,为

  7. Balloon Flight Background Measurement with Actively-Shielded Planar and Imaging CZT Detectors

    OpenAIRE

    Bloser, P. F.; Narita, T; Jenkins, J. A.; Perrin, M.; Murray, R.; Grindlay, J.E.

    2001-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as ``CZT1,'' consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator surrounded by plastic scintillator and a thick BGO crystal in the rear. The second detector, ``CZT2,'' comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Product...

  8. Status of development of gamma-ray detector response function code or GAMDRF.

    Science.gov (United States)

    Li, Fusheng; Han, Xiaogang

    2012-07-01

    The need for an accurate representation of the detector response functions (DRFs) for sodium iodide (NaI), bismuth germinate (BGO), etc., arises in the oilwell logging business, especially important for spectral logging tools such as a geochemical logging tool. While Monte Carlo models predict the photon spectra incidents on these detectors, the DRFs are used to generate the pulse-height spectra. A Monte Carlo-based γ-ray detector response function code (GAMDRF) was developed to meet the requirements based on complete photon physics.

  9. Development of a Compton camera for medical applications based on silicon strip and scintillation detectors

    Science.gov (United States)

    Krimmer, J.; Ley, J.-L.; Abellan, C.; Cachemiche, J.-P.; Caponetto, L.; Chen, X.; Dahoumane, M.; Dauvergne, D.; Freud, N.; Joly, B.; Lambert, D.; Lestand, L.; Létang, J. M.; Magne, M.; Mathez, H.; Maxim, V.; Montarou, G.; Morel, C.; Pinto, M.; Ray, C.; Reithinger, V.; Testa, E.; Zoccarato, Y.

    2015-07-01

    A Compton camera is being developed for the purpose of ion-range monitoring during hadrontherapy via the detection of prompt-gamma rays. The system consists of a scintillating fiber beam tagging hodoscope, a stack of double sided silicon strip detectors (90×90×2 mm3, 2×64 strips) as scatter detectors, as well as bismuth germanate (BGO) scintillation detectors (38×35×30 mm3, 100 blocks) as absorbers. The individual components will be described, together with the status of their characterization.

  10. Development of a Compton camera for medical applications based on silicon strip and scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Krimmer, J., E-mail: j.krimmer@ipnl.in2p3.fr [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Ley, J.-L. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Abellan, C.; Cachemiche, J.-P. [Aix-Marseille Université, CNRS/IN2P3, CPPM UMR 7346, 13288 Marseille (France); Caponetto, L.; Chen, X.; Dahoumane, M.; Dauvergne, D. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Freud, N. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Joly, B.; Lambert, D.; Lestand, L. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Létang, J.M. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Magne, M. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); and others

    2015-07-01

    A Compton camera is being developed for the purpose of ion-range monitoring during hadrontherapy via the detection of prompt-gamma rays. The system consists of a scintillating fiber beam tagging hodoscope, a stack of double sided silicon strip detectors (90×90×2 mm{sup 3}, 2×64 strips) as scatter detectors, as well as bismuth germanate (BGO) scintillation detectors (38×35×30 mm{sup 3}, 100 blocks) as absorbers. The individual components will be described, together with the status of their characterization.

  11. Space-variant optical correlator based on the fractional Fourier transform: implementation by the use of a photorefractive Bi(12)GeO(2(a)) (BGO) holographic filter.

    Science.gov (United States)

    Granieri, S; Del Carmen Lasprilla, M; Bolognini, N; Sicre, E E

    1996-12-10

    A space-variant optical correlator is proposed on the basis of the fractional Fourier transform. The optical device uses as a recording medium for the holographic filter a photorefractive Bi(12)GeO(2) (BGO) crystal. The experimental results confirm the shift-variance properties. Some limitations that arise from the volume diffraction are also considered.

  12. Development of whole energy absorption spectrometer for decay heat measurement on fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Fujio; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    To measure decay heat on fusion reactor materials irradiated by D-T neutrons, a Whole Energy Absorption Spectrometer (WEAS) consisting of a pair of large BGO (bismuth-germanate) scintillators was developed. Feasibility of decay heat measurement with WEAS for various materials and for a wide range of half-lives (seconds - years) was demonstrated by experiments at FNS. Features of WEAS, such as high sensitivity, radioactivity identification, and reasonably low experimental uncertainty of {approx} 10 %, were found. (author)

  13. A Vacuum Ultraviolet Absorption Array Spectrometer as a Selective Detector for Comprehensive Two-Dimensional Gas Chromatography: Concept and First Results.

    Science.gov (United States)

    Gröger, Thomas; Gruber, Beate; Harrison, Dale; Saraji-Bozorgzad, Mohammad; Mthembu, Makhosazana; Sutherland, Aimée; Zimmermann, Ralf

    2016-03-15

    Fast and selective detectors are very interesting for comprehensive two-dimensional gas chromatography (GC × GC). This is particularly true if the detector system can provide additional spectroscopic information on the compound structure and/or functionality. Other than mass spectrometry (MS), only optical spectroscopic detectors are able to provide selective spectral information. However, until present the application of optical spectroscopy technologies as universal detectors for GC × GC has been restricted mainly due to physical limitations such as insufficient acquisition speed or high detection limits. A recently developed simultaneous-detection spectrometer working in the vacuum ultraviolet (VUV) region of 125-240 nm overcomes these limitations and meets all the criteria of a universal detector for GC × GC. Peak shape and chromatographic resolution is preserved and unique spectral information, complementary to mass spectrometry data, is gained. The power of this detector is quickly recognized as it has the ability to discriminate between isomeric compounds or difficult to separate structurally related isobaric species; thus, it provides additional selectivity. A further promising feature of this detector is the data analysis concept of spectral filtering, which is accomplished by targeting special electronic transitions that allows for a fast screening of GC × GC chromatograms for designated compound classes.

  14. Clinical evaluation of 2D versus 3D whole-body PET image quality using a dedicated BGO PET scanner

    Energy Technology Data Exchange (ETDEWEB)

    Visvikis, D. [CHU Morvan, U650 INSERM, Laboratoire de Traitement de l' Information Medicale (LaTIM), Brest (France); Griffiths, D. [Lister Healthcare, London PET Centre, London (United Kingdom); Costa, D.C. [Middlesex Hospital, Institute of Nuclear Medicine, Royal Free and University College Medical School, London (United Kingdom); HPP Medicina Molecular, SA Porto (Portugal); Bomanji, J.; Ell, P.J. [Middlesex Hospital, Institute of Nuclear Medicine, Royal Free and University College Medical School, London (United Kingdom)

    2005-09-01

    Three-dimensional positron emission tomography (3D PET) results in higher system sensitivity, with an associated increase in the detection of scatter and random coincidences. The objective of this work was to compare, from a clinical perspective, 3D and two-dimensional (2D) acquisitions in terms of whole-body (WB) PET image quality with a dedicated BGO PET system. 2D and 3D WB emission acquisitions were carried out in 70 patients. Variable acquisition parameters in terms of time of emission acquisition per axial field of view (aFOV) and slice overlap between sequential aFOVs were used during the 3D acquisitions. 3D and 2D images were reconstructed using FORE+WLS and OSEM respectively. Scatter correction was performed by convolution subtraction and a model-based scatter correction in 2D and 3D respectively. All WB images were attenuation corrected using segmented transmission scans. Images were blindly assessed by three observers for the presence of artefacts, confidence in lesion detection and overall image quality using a scoring system. Statistically significant differences between 2D and 3D image quality were only obtained for 3D emission acquisitions of 3 min. No statistically significant differences were observed for image artefacts or lesion detectability scores. Image quality correlated significantly with patient weight for both modes of operation. Finally, no differences were seen in image artefact scores for the different axial slice overlaps considered, suggesting the use of five slice overlaps in 3D WB acquisitions. 3D WB imaging using a dedicated BGO-based PET scanner offers similar image quality to that obtained in 2D considering similar overall times of acquisitions. (orig.)

  15. Development of wide-band GRB detectors and the GRB monitor for the CALET Experiment

    Science.gov (United States)

    Yoshida, Atsumasa; Yamaoka, Kazutaka; Nakagawa, Yujin; Nakahira, Satoshi; Sugita, Satoshi; Tomida, Hiroshi; Torii, Shoji

    Many previous observations revealed radiations from GRBs to be widely emitted in electromagnetic energy band form less than a keV to over a GeV range, and peak-energies of νFν spectra to be distributed rather more widely than expected before. Those includes soft events explored by Ginga, BeppoSAX and HETE-2, and delayed GeV emissions and additional hard continuum detected by EGRET. It is very important to have a GRB monitor in space to be sensitive to photons in continuously wide energy range. We are developing wide-band GRB detectors utilizing several kinds of scintillator and X-ray CCD for future space missions. One of these detectors is that proposed as a GRB Monitor for the CALorimetric Electron Telescope (CALET) mission that was selected for Phase A/B studies as a next experiment for JEM-EF of ISS. The GRB Monitor (GBM) is a part of this experiment to extend scientific products achieved by CALET which can detect gamma-rays in a range from about 20MeV to TeV by itself and is potentially sensitive to hard radiations from GRBs. GBM is designed as multiple scintillation counters made of BGO and LaBr3 (Ce) to detect GRBs in a few keV to about 20MeV range alone, and to cover the energy band continuously up-to TeV region together with the CALET's main instruments, Imaging Calorimeter (IMC) and Total Absorption Calorimeter (TASC); one can expect sensitive range of nine orders of magnitude for GRBs inside the IMC's FOV of about 1.8 str. We present current status of our study including preliminary experimental results for LaBr3 (Ce) using a proton accelerator, and the design and expected ability of CALET-GBM.

  16. Development of high performance Avalanche Photodiodes and dedicated analog systems for HXI/SGD detectors onboard the Astro-H mission

    Science.gov (United States)

    Saito, T.; Nakamori, T.; Yoshino, M.; Mizoma, H.; Kataoka, J.; Kawakami, K.; Yatsu, Y.; Ohno, M.; Goto, K.; Hanabata, Y.; Takahashi, H.; Fukazawa, Y.; Sasano, M.; Torii, S.; Uchiyama, H.; Nakazawa, K.; Makishima, K.; Watanabe, S.; Kokubun, M.; Takahashi, T.; Mori, K.; Tajima, H.; Astro-H HXI/SGD Team

    2013-01-01

    Hard X-ray Imager and Soft Gamma-ray Detector are being developed as onboard instruments for the Astro-H mission, which is scheduled for launch in 2014. In both detectors, BGO scintillators play key roles in achieving high sensitivity in low Earth orbit (LEO), by generating active veto signals to reject cosmic-ray events and gamma-ray backgrounds from radio-activated detector materials. In order to maximize background rejection power, it is also important to minimize the energy threshold of this shield. As a readout sensor of weak scintillation light from a number of BGO crystals in a complicated detector system, high performance, reverse-type Avalanche Photodiodes (APDs), with an effective area of 10×10 mm2 are being employed, instead of bulky photomultiplier tubes (PMTs).Another advantage of using APDs is their low power consumption, although the relatively low gain of APDs (compared to conventional PMTs) requires dedicated analog circuits for noise suppression. In this paper, we report on the development and performance of APD detectors specifically designed for the Astro-H mission. In addition to APD performance, various environmental tests, including radiation hardness and qualification thermal cycling, will be described in detail. Moreover, a dedicated charge sensitive amplifier and analog filters are newly developed and tested here to optimize the performance of APDs to activate fast veto signals within a few μs from the BGO trigger. We will also report on overall performance testing of a prototype BGO detector system that mimics the data acquisition system onboard Astro-H.

  17. A DOI Detector With Crystal Scatter Identification Capability for High Sensitivity and High Spatial Resolution PET Imaging

    OpenAIRE

    2015-01-01

    A new phoswich detector is being developed at the Crump Institute, aiming to provide improvements in sensitivity, and spatial resolution for PET. The detector configuration is comprised of two layers of pixelated scintillator crystal arrays, a glass light guide and a light detector. The annihilation photon entrance (top) layer is a 48 × 48 array of 1.01 × 1.01 × 7 mm3 LYSO crystals. The bottom layer is a 32 × 32 array of 1.55 × 1.55 × 9 mm3 BGO crystals. A tapered, multiple-element glass ligh...

  18. Performance evaluation of a very high resolution small animal PET imager using silicon scatter detectors

    Science.gov (United States)

    Park, Sang-June; Rogers, W. Leslie; Huh, Sam; Kagan, Harris; Honscheid, Klaus; Burdette, Don; Chesi, Enrico; Lacasta, Carlos; Llosa, Gabriela; Mikuz, Marko; Studen, Andrej; Weilhammer, Peter; Clinthorne, Neal H.

    2007-05-01

    A very high resolution positron emission tomography (PET) scanner for small animal imaging based on the idea of inserting a ring of high-granularity solid-state detectors into a conventional PET scanner is under investigation. A particularly interesting configuration of this concept, which takes the form of a degenerate Compton camera, is shown capable of providing sub-millimeter resolution with good sensitivity. We present a Compton PET system and estimate its performance using a proof-of-concept prototype. A prototype single-slice imaging instrument was constructed with two silicon detectors 1 mm thick, each having 512 1.4 mm × 1.4 mm pads arranged in a 32 × 16 array. The silicon detectors were located edgewise on opposite sides and flanked by two non-position sensitive BGO detectors. The scanner performance was measured for its sensitivity, energy, timing, spatial resolution and resolution uniformity. Using the experimental scanner, energy resolution for the silicon detectors is 1%. However, system energy resolution is dominated by the 23% FWHM BGO resolution. Timing resolution for silicon is 82.1 ns FWHM due to time-walk in trigger devices. Using the scattered photons, time resolution between the BGO detectors is 19.4 ns FWHM. Image resolution of 980 µm FWHM at the center of the field-of-view (FOV) is obtained from a 1D profile of a 0.254 mm diameter 18F line source image reconstructed using the conventional 2D filtered back-projection (FBP). The 0.4 mm gap between two line sources is resolved in the image reconstructed with both FBP and the maximum likelihood expectation maximization (ML-EM) algorithm. The experimental instrument demonstrates sub-millimeter resolution. A prototype having sensitivity high enough for initial small animal images can be used for in vivo studies of small animal models of metabolism, molecular mechanism and the development of new radiotracers.

  19. Performance evaluation of continuous blood sampling system for PET study. Comparison of three detector-systems

    CERN Document Server

    Matsumoto, K; Sakamoto, S; Senda, M; Yamamoto, S; Tarutani, K; Minato, K

    2002-01-01

    To measure cerebral blood flow with sup 1 sup 5 O PET, it is necessary to measure the time course of arterial blood radioactivity. We examined the performance of three different types of continuous blood sampling system. Three kinds of continuous blood sampling system were used: a plastic scintillator-based beta detector (conventional beta detector (BETA)), a bismuth germinate (BGO)-based coincidence gamma detector (Pico-count flow-through detector (COINC)) and a Phoswich detector (PD) composed by a combination of plastic scintillator and BGO scintillator. Performance of these systems was evaluated for absolute sensitivity, count rate characteristic, sensitivity to background gamnra photons, and reproducibility for nylon tube geometry. The absolute sensitivity of the PD was 0.21 cps/Bq for sup 6 sup 8 Ga positrons at the center of the detector. This was approximately three times higher than BETA, two times higher than COINC. The value measured with BETA was stable, even when background radioactivity was incre...

  20. PoGOLino: a scintillator-based balloon-borne neutron detector

    CERN Document Server

    Kole, Merlin; Fukazawa, Yasushi; Fukuda, Kentaro; Ishizu, Sumito; Jackson, Miranda; Kamae, Tune; Kawaguchi, Noriaki; Kawano, Takafumi; Kiss, Mozsi; Moretti, Elena; Pearce, Mark; Rydström, Stefan; Takahashi, Hiromitsu; Yanagida, Takayuki

    2014-01-01

    PoGOLino is a balloon-borne scintillator-based experiment developed to study the largely unexplored high altitude neutron environment at high geomagnetic latitudes. The instrument comprises two detectors that make use of LiCAF, a novel neutron sensitive scintillator, sandwiched by BGO crystals for background reduction. The experiment was launched on March 20th 2013 from the Esrange Space Centre, Northern Sweden (geomagnetic latitude of $65^\\circ$), for a three hour flight during which the instrument took data up to an altitude of 30.9 km. The detector design and ground calibration results are presented together with the measurement results from the balloon flight.

  1. Highly photocatalytic activity of novel Fe-MIL-88B/GO nanocomposite in the degradation of reactive dye from aqueous solution

    Science.gov (United States)

    Vu, Tuan A.; Le, Giang H.; Vu, Hoa T.; Nguyen, Kien T.; Quan, Trang T. T.; Nguyen, Quang K.; Tran, Hoa T. K.; Dang, Phuong T.; Vu, Loi D.; Lee, Gun D.

    2017-03-01

    An Fe-MIL-88B/graphene oxide (GO) composite was successfully synthesized by the hydrofluoric acid (HF) free-solvothermal method. The sample was characterized by x-ray diffraction (XRD), N2 adsorption-desorption Brunauer-Emmett-Teller (BET) method, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and x-ray photoelectron spectroscopy (XPS). BET shows that Fe-MIL-88B/GO is of a mesoporous structure, while XRD and XPS results reveal that besides the Fe-MIL-88B phase, a new α-FeOOH phase in the novel Fe-MIL-88B/GO composite is formed. The as-prepared Fe-MIL-88B/GO nanocomposite was used to test the photocatalytic degradation of reactive dye (reactive red-RR195) from aqueous solution. This novel metal-organic framework (MOF)/GO composite exhibited excellent photocatalytic activity. Thus, after 25 min of reaction under simulated sunlight irradiation, removal efficiency reached 98%. Moreover, this composite still maintained high photocatalytic activity after three cycles of reaction runs, indicating its high stability and reusability. This opens a new application potential for MOF/GO as a highly efficient photo-Fenton catalyst.

  2. Invited article: The fast readout low noise camera as a versatile x-ray detector for time resolved dispersive extended x-ray absorption fine structure and diffraction studies of dynamic problems in materials science, chemistry, and catalysis

    Science.gov (United States)

    Labiche, Jean-Claude; Mathon, Olivier; Pascarelli, Sakura; Newton, Mark A.; Ferre, Gemma Guilera; Curfs, Caroline; Vaughan, Gavin; Homs, Alejandro; Carreiras, David Fernandez

    2007-09-01

    Originally conceived and developed at the European Synchrotron Radiation Facility (ESRF) as an "area" detector for rapid x-ray imaging studies, the fast readout low noise (FReLoN) detector of the ESRF [J.-C. Labiche, ESRF Newsletter 25, 41 (1996)] has been demonstrated to be a highly versatile and unique detector. Charge coupled device (CCD) cameras at present available on the public market offer either a high dynamic range or a high readout speed. A compromise between signal dynamic range and readout speed is always sought. The parameters of the commercial cameras can sometimes be tuned, in order to better fulfill the needs of specific experiments, but in general these cameras have a poor duty cycle (i.e., the signal integration time is much smaller than the readout time). In order to address scientific problems such as time resolved experiments at the ESRF, a FReLoN camera has been developed by the Instrument Support Group at ESRF. This camera is a low noise CCD camera that combines high dynamic range, high readout speed, accuracy, and improved duty cycle in a single image. In this paper, we show its application in a quasi-one-dimensional sense to dynamic problems in materials science, catalysis, and chemistry that require data acquisition on a time scale of milliseconds or a few tens of milliseconds. It is demonstrated that in this mode the FReLoN can be applied equally to the investigation of rapid changes in long range order (via diffraction) and local order (via energy dispersive extended x-ray absorption fine structure) and in situations of x-ray hardness and flux beyond the capacity of other detectors.

  3. Silicon Detectors for PET and SPECT

    Science.gov (United States)

    Cochran, Eric R.

    silicon detectors to serve as the electronic collimator in these systems. The second prototype is a high resolution PET system. By inserting a silicon PET ring inside a conventional scintillator PET ring, it has been proposed that both image resolution and system sensitivity can be increased. To investigate these claims, a partial BGO ring with clinical PET dimensions (50 cm inner diameter) has been constructed that can be used to evaluate a variety of system configurations. Initial investigations use two back-to-back high resolution silicon detectors in a 2D geometry with a small (10 cm) field of view. This configuration is used to demonstrate the potential performance of a specialized small animal imaging device for medical research applications. Initial filtered backprojection images of a 22Na point source have shown the spatial resolution of the system to be 950 mum for the pure silicon events, 1.8 mm for the hybrid silicon-BGO events, and 7 mm for the pure BGO events. The performance is consistent with expectations and, as the first real images from this type of device, the results provide motivation to continue the investigation of the high resolution PET concept.

  4. Robust and economical multi-sample, multi-wavelength UV/vis absorption and fluorescence detector for biological and chemical contamination

    CERN Document Server

    Lu, Peter J; Macarthur, James B; Sims, Peter A; Ma, Hongshen; Slocum, Alexander H

    2012-01-01

    We present a portable multi-channel, multi-sample UV/vis absorption and fluorescence detection device, which has no moving parts, can operate wirelessly and on batteries, interfaces with smart mobile phones or tablets, and has the sensitivity of commercial instruments costing an order of magnitude more. We use UV absorption to measure the concentration of ethylene glycol in water solutions at all levels above those deemed unsafe by the United States Food and Drug Administration; in addition we use fluorescence to measure the concentration of d-glucose. Both wavelengths can be used concurrently to increase measurement robustness and increase detection sensitivity. Our small robust economical device can be deployed in the absence of laboratory infrastructure, and therefore may find applications immediately following natural disasters, and in more general deployment for much broader-based testing of food, agricultural and household products to prevent outbreaks of poisoning and disease.

  5. Measurement of the neutron capture cross section of the fissile isotope $^{235}$U with the CERN n_TOF Total Absorption Calorimeter and a fission tagging based on micromegas detectors

    CERN Document Server

    Mendoza, E; Cano-Ott, D; Guerrero, C; Berthoumieux, E; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Bécares, V; Becvár, F; Belloni, F; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calviño, F; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortés, G; Cortés-Giraldo, M A; Diakaki, M; Domingo-Pardo, C; Duran, I; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; García, A R; Giubrone, G; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Gunsing, F; Gurusamy, P; Jenkins, D G; Jericha, E; Kadi, Y; Käppeler, F; Karadimos, D; Kawano, T; Kivel, N; Koehler, P; Kokkoris, M; Korschinek, G; Krticka, M; Kroll, J; Langer, C; Lampoudis, C; Leal-Cidoncha, E; Lederer, C; Leeb, H; Leong, L S; Losito, R; Manousos, A; Marganiec, J; Martínez, T; Mastinu, P F; Mastromarco, M; Massimi, C; Meaze, M; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondelaers, W; Paradela, C; Pavlik, A; Perkowski, J; Pignatari, M; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Schumann, D; Stetcu, I; Sabaté, M; Tagliente, G; Tain, J L; Tarrío, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiss, C; Wright, T; Zugec, P

    2014-01-01

    Actual and future nuclear technologies require more accurate nuclear data on the (n, $\\gamma$) cross sections and $\\alpha$-ratios of fissile isotopes. Their measurement presents several difficulties, mainly related to the strong fission $\\gamma$-ray background competing with the weaker $\\gamma$-ray cascades used as the experimental signature of the (n, $\\gamma$) process. A specific setup has been used at the CERN n_TOF facility in 2012 for the measurement of the (n,$\\gamma$ ) cross section and $\\alpha$- ratios of fissile isotopes and used for the case of the $^{235}$U isotope. The setup consists in a set of micromegas fission detectors surrounding $^{235}$U samples and placed inside the segmented BaF$_2$ Total Absorption Calorimeter.

  6. Measurement of the Neutron Capture Cross Section of the Fissile Isotope 235U with the CERN n_TOF Total Absorption Calorimeter and a Fission Tagging Based on Micromegas Detectors

    CERN Document Server

    Balibrea, J; Cano-Ott, D; Guerrero, C; Berthoumieux, E; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Bécares, V; Bečvář, F; Belloni, F; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calviño, F; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortés, G; Cortés-Giraldo, M A; Diakaki, M; Domingo-Pardo, C; Duran, I; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; García, A R; Giubrone, G; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Gunsing, F; Gurusamy, P; Jenkins, D G; Jericha, E; Kadi, Y; Käppeler, F; Karadimos, D; Kawano, T; Kivel, N; Koehler, P; Kokkoris, M; Korschinek, G; Krtička, M; Kroll, J; Langer, C; Lampoudis, C; Lederer, C; Leeb, H; Leong, L S; Losito, R; Manousos, A; Marganiec, J; Martínez, T; Mastinu, P F; Mastromarco, M; Massimi, C; Meaze, M; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondelaers, W; Paradela, C; Pavlik, A; Perkowski, J; Pignatari, M; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Schumann, D; Stetcu, I; Sabaté, M; Tagliente, G; Tain, J L; Tarrío, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiß, C; Wright, T J; Žugec, P

    Current and future nuclear technologies require more accurate nuclear data on (n,γ) cross sections and the α-ratios of fissile isotopes. Their measurement presents several difficulties, mainly related to the strong fission γ-ray background competing with the weaker γ-ray cascades used as the experimental signature of the (n,γ) process. A specific setup was used at the CERN n_TOF facility in 2012 for the measurement of the (n,γ) cross section and α-ratios of fissile isotopes and used for the case of the 235U isotope. The setup consists of a set of micromegas fission detectors surrounding the 235U samples all placed inside a segmented BaF2 Total Absorption Calorimeter.

  7. 硅漂移探测器用于X射线标识谱与吸收实验%Silicon drift detector for characteristic X-ray spectrum and absorption experiment

    Institute of Scientific and Technical Information of China (English)

    冉书能; 贾春燕; 吴思诚

    2016-01-01

    利用硅漂移探测器测量不同元素的标识X射线,验证莫塞莱定律,计算屏蔽系数并解释其变化规律。利用不同厚度的镍吸收片做铜的标识X射线吸收,结果表明:单色化铜的标识X射线所需镍片的最佳厚度约为20μm 。%The characteristic X‐ray spectrum was measured using silicon drift detector ,the Mose‐ley law was verified ,and the shielding coefficient and its variation was calculated and explained .The absorption of the characteristic X‐ray spectrum of copper was investigated using nickel absorption sheets of different thickness .It was concluded that the optimum thickness of the nickel sheet required for the monochromatization of Cu characteristic spectrum was about 20 μm .

  8. The HOTWAXS detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E.; Derbyshire, G.E. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Diakun, G. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Duxbury, D.M. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)], E-mail: d.m.duxbury@rl.ac.uk; Fairclough, J.P.A. [Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF (United Kingdom); Harvey, I.; Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Lipp, J.D.; Marsh, A.S.; Salisbury, J. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Sankar, G. [Royal Institution of GB, 21 Albemarle Street, London W1S 4BS (United Kingdom); Spill, E.J.; Stephenson, R. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Terrill, N.J. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom)

    2007-10-11

    The development and testing of the HOTWAXS position-sensitive X-ray detector for Synchrotron Radiation Sources is described. Funded from a facility development grant, the aim of the project was to produce a high counting rate, parallax-free photon counting detector to be used in the combined studies of X-ray absorption fine structure and X-ray diffraction (XAFS/XRD), and also in the technique of small angle and wide angle X-ray scattering (SAXS/WAXS). The detector system is described together with results of experiments carried out at the Daresbury Laboratory Synchrotron Radiation Source.

  9. Comparison of Anger camera and BGO mosaic position-sensitive detectors for `Super ACAR`. Precision electron momentum densities via angular correlation of annihilation radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mills, A.P. Jr. [Bell Labs. Murray Hill, NJ (United States); West, R.N.; Hyodo, Toshio

    1997-03-01

    We discuss the relative merits of Anger cameras and Bismuth Germanate mosaic counters for measuring the angular correlation of positron annihilation radiation at a facility such as the proposed Positron Factory at Takasaki. The two possibilities appear equally cost effective at this time. (author)

  10. A gamma- and X-ray detector for cryogenic, high magnetic field applications

    CERN Document Server

    Cooper, R L; Bales, M J; Bass, C D; Beise, E J; Breuer, H; Byrne, J; Chupp, T E; Coakley, K J; Dewey, M S; Fu, C; Gentile, T R; Mumm, H P; Nico, J S; O'Neill, B; Pulliam, K; Thompson, A K; Wietfeldt, F E

    2012-01-01

    As part of an experiment to measure the spectrum of photons emitted in beta-decay of the free neutron, we developed and operated a detector consisting of 12 bismuth germanate (BGO) crystals coupled to avalanche photodiodes (APDs). The detector was operated near liquid nitrogen temperature in the bore of a superconducting magnet and registered photons with energies from 5 keV to 1000 keV. To enlarge the detection range, we also directly detected soft X-rays with energies between 0.2 keV and 20 keV with three large area APDs. The construction and operation of the detector is presented, as well as information on operation of APDs at cryogenic temperatures.

  11. Detector Unit

    CERN Multimedia

    1960-01-01

    Original detector unit of the Instituut voor Kernfysisch Onderzoek (IKO) BOL project. This detector unit shows that silicon detectors for nuclear physics particle detection were already developed and in use in the 1960's in Amsterdam. Also the idea of putting 'strips' onto the silicon for high spatial resolution of a particle's impact on the detector were implemented in the BOL project which used 64 of these detector units. The IKO BOL project with its silicon particle detectors was designed, built and operated from 1965 to roughly 1977. Detector Unit of the BOL project: These detectors, notably the ‘checkerboard detector’, were developed during the years 1964-1968 in Amsterdam, The Netherlands, by the Natuurkundig Laboratorium of the N.V. Philips Gloeilampen Fabrieken. This was done in close collaboration with the Instituut voor Kernfysisch Onderzoek (IKO) where the read-out electronics for their use in the BOL Project was developed and produced.

  12. Infrared detectors

    CERN Document Server

    Rogalski, Antonio

    2010-01-01

    This second edition is fully revised and reorganized, with new chapters concerning third generation and quantum dot detectors, THz detectors, cantilever and antenna coupled detectors, and information on radiometry and IR optics materials. Part IV concerning focal plane arrays is significantly expanded. This book, resembling an encyclopedia of IR detectors, is well illustrated and contains many original references … a really comprehensive book.-F. Sizov, Institute of Semiconductor Physics, National Academy of Sciences, Kiev, Ukraine

  13. Gaseous Detectors: Charged Particle Detectors - Particle Detectors and Detector Systems

    CERN Document Server

    Hilke, H J

    2011-01-01

    Gaseous Detectors in 'Charged Particle Detectors - Particle Detectors and Detector Systems', part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B1: Detectors for Particles and Radiation. Part 1: Principles and Methods'. This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Subsection '3.1.2 Gaseous Detectors' of Section '3.1 Charged Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.1.2 Gaseous Detectors 3.1.2.1 Introduction 3.1.2.2 Basic Processes 3.1.2.2.1 Gas ionization by charged particles 3.1.2.2.1.1 Primary clusters 3.1.2.2.1.2 Cluster size distribution 3.1.2.2.1.3 Total number of ion pairs 3.1.2.2.1.4 Dependence of energy deposit on particle velocity 3.1.2.2.2 Transport of...

  14. A Study of Active Shielding Optimized for 1-80 keV Wide-Band X-ray Detector in Space

    CERN Document Server

    Furuta, Yoshihiro; Hiraga, Junko S; Sasano, Makoto; Murakami, Hiroaki; Nakazawa, Kazuhiro

    2015-01-01

    Active shielding is an effective technique to reduce background signals in hard X-ray detectors and to enable observing darker sources with high sensitivity in space. Usually the main detector is covered with some shield detectors made of scintillator crystals such as BGO (Bi$_4$Ge$_3$O$_{12}$), and the background signals are filtered out using anti-coincidence among them. Japanese X-ray observing satellites "Suzaku" and "ASTRO-H" employed this technique in their hard X-ray instruments observing at > 10 keV. In the next generation X-ray satellites, such as the NGHXT proposal, a single hybrid detector is expected to cover both soft (1-10 keV) and hard (> 10 keV) X-rays for effectiveness. However, present active shielding is not optimized for the soft X-ray band, 1-10 keV. For example, Bi and Ge, which are contained in BGO, have their fluorescence emission lines around 10 keV. These lines appear in the background spectra obtained by ASTRO-H Hard X-ray Imager, which are non-negligible in its observation energy b...

  15. Nonequilibrium superconducting detectors

    Science.gov (United States)

    Cristiano, R.; Ejrnaes, M.; Esposito, E.; Lisitskyi, M. P.; Nappi, C.; Pagano, S.; Perez de Lara, D.

    2006-03-01

    Nonequilibrium superconducting detectors exploit the early stages of the energy down cascade which occur after the absorption of radiation. They operate on a short temporal scale ranging from few microseconds down to tens of picoseconds. In such a way they provide fast counting capability, high time discrimination and also, for some devices, energy sensitivity. Nonequilibrium superconducting detectors are developed for their use both in basic science and in practical applications for detection of single photons or single ionized macromolecules. In this paper we consider two devices: distributed readout imaging detectors (DROIDs) based on superconducting tunnel junctions (STJs), which are typically used for high-speed energy spectroscopy applications, and hot-electron superconductive detectors (HESDs), which are typically used as fast counters and time discriminators. Implementation of the DROID geometry to use a single superconductor is discussed. Progress in the fabrication technology of NbN nanostructured HESDs is presented. The two detectors share the high sensitivity that makes them able to efficiently detect even single photons down to infrared energy.

  16. Nonequilibrium superconducting detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, R [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Ejrnaes, M [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); INFN Sezione di Napoli, 80126 Naples (Italy); Esposito, E [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Lisitskyi, M P [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Nappi, C [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Pagano, S [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Dipartimento di Fisica, Universita di Salerno, 84081 Baronissi (Saudi Arabia) (Italy); Perez de Lara, D [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy)

    2006-03-15

    Nonequilibrium superconducting detectors exploit the early stages of the energy down cascade which occur after the absorption of radiation. They operate on a short temporal scale ranging from few microseconds down to tens of picoseconds. In such a way they provide fast counting capability, high time discrimination and also, for some devices, energy sensitivity. Nonequilibrium superconducting detectors are developed for their use both in basic science and in practical applications for detection of single photons or single ionized macromolecules. In this paper we consider two devices: distributed readout imaging detectors (DROIDs) based on superconducting tunnel junctions (STJs), which are typically used for high-speed energy spectroscopy applications, and hot-electron superconductive detectors (HESDs), which are typically used as fast counters and time discriminators. Implementation of the DROID geometry to use a single superconductor is discussed. Progress in the fabrication technology of NbN nanostructured HESDs is presented. The two detectors share the high sensitivity that makes them able to efficiently detect even single photons down to infrared energy.

  17. Scintillation detectors in computerized tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gilar, O.; Pavlicek, Z.; Jursova, L. (Tesla, Premysleni (Czechoslovakia). Vyzkumny Ustav Pristroju Jaderne Techniky)

    1984-07-01

    A new scintillator, Bi/sub 4/Ge/sub 3/O/sub 12/ (BGO), was tested for use in the detection part of computerized tomographs. In comparison with the NaI(Tl) scintillator it has a three-fold mass stopping power and allows the detection of medium and high energy gamma radiation with a higher detection efficiency, i.e., for the same detection efficiency its size is much smaller. Some other mechanical, physical and optical parameters of the BGO scintillator are given. BGO is prospective for use in high energy spectrometry and may replace NaI(Tl) wherever the following parameters are significant: crystal size, detection efficiency for gamma radiation, and good spatial resolution.

  18. Total light absorption in graphene

    CERN Document Server

    Thongrattanasiri, Sukosin; de Abajo, F Javier Garcia

    2011-01-01

    We demonstrate that 100% light absorption can take place in a single patterned sheet of doped graphene. General analysis shows that a planar array of small lossy particles exhibits full absorption under critical-coupling conditions provided the cross section of each individual particle is comparable to the area of the lattice unit-cell. Specifically, arrays of doped graphene nanodisks display full absorption when supported on a substrate under total internal reflection, and also when lying on a dielectric layer coating a metal. Our results are relevant for infrared light detectors and sources, which can be made tunable via electrostatic doping of graphene.

  19. Pixel Detectors

    OpenAIRE

    Wermes, Norbert

    2005-01-01

    Pixel detectors for precise particle tracking in high energy physics have been developed to a level of maturity during the past decade. Three of the LHC detectors will use vertex detectors close to the interaction point based on the hybrid pixel technology which can be considered the state of the art in this field of instrumentation. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as the very harsh...

  20. Development of a simple detector response function generation program: the CEARDRFs code.

    Science.gov (United States)

    Wang, Jiaxin; Wang, Zhijian; Peeples, Johanna; Yu, Huawei; Gardner, Robin P

    2012-07-01

    A simple Monte Carlo program named CEARDRFs has been developed to generate very accurate detector response functions (DRFs) for scintillation detectors. It utilizes relatively rigorous gamma-ray transport with simple electron transport, and accounts for two phenomena that have rarely been treated: scintillator non-linearity and the variable flat continuum part of the DRF. It has been proven that these physics and treatments work well for 3×3″ and 6×6″ cylindrical NaI detector in CEAR's previous work. Now this approach has been expanded to cover more scintillation detectors with various common shapes and sizes. Benchmark experiments of 2×2″ cylindrical BGO detector and 2×4×16″ rectangular NaI detector have been carried out at CEAR with various radiactive sources. The simulation results of CEARDRFs have also been compared with MCNP5 calculations. The benchmark and comparison show that CEARDRFs can generate very accurate DRFs (more accurate than MCNP5) at a very fast speed (hundred times faster than MCNP5). The use of this program can significantly increase the accuracy of applications relying on detector spectroscopy like prompt gamma-ray neutron activation analysis, X-ray fluorescence analysis, oil well logging and homeland security. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Metal Detectors.

    Science.gov (United States)

    Harrington-Lueker, Donna

    1992-01-01

    Schools that count on metal detectors to stem the flow of weapons into the schools create a false sense of security. Recommendations include investing in personnel rather than hardware, cultivating the confidence of law-abiding students, and enforcing discipline. Metal detectors can be quite effective at afterschool events. (MLF)

  2. Optical Detectors

    Science.gov (United States)

    Tabbert, Bernd; Goushcha, Alexander

    Optical detectors are applied in all fields of human activities from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

  3. Calibration of Li-glass Detector Efficiency

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Li-glass detector will be used to measure the flux of neutron beam in Gamma-ray Total Absorption Facility(GTAF). We have calibrated the detection efficiency of Li-glass detector in 5SDH-2 accelerator. The beam of neutron was produced by the reaction 7Li

  4. Optimization of the performance of a CsI(Tl) scintillator + Si pin photodiode detector for medium energy light charged particle hybride array

    CERN Document Server

    Kalinka, G; Gál, J; Hegyesi, G; Molnár, J; Elekes, Z; Motobayashi, T; Yanagisawa, Y; Saito, A

    2003-01-01

    NaI(TI), BGO and CsI(TI) crystals in compact arrays will be used at RIKEN RI Beam Factory in the near future to detect gamma-rays from fast moving nuclei produced in nuclear reactions with radioactive beams, and among them CsI(TI) for light charged particle identification as well. The latter system will consist of 312 Cs(TI) crystals coupled to silicon photodiodes in a hemispherical arrangement, four detectors packed together with their own preamplifiers in each of the 78 parallelepipedic thin walled aluminum containers. (R.P.)

  5. Balloon Flight Background Measurement with Actively-Shielded Planar and Imaging CZT Detectors

    CERN Document Server

    Bloser, P F; Jenkins, J A; Perrin, M; Murray, R; Grindlay, J E

    2001-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as ``CZT1,'' consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator surrounded by plastic scintillator and a thick BGO crystal in the rear. The second detector, ``CZT2,'' comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Products high pressure Bridgman material and the other of IMARAD horizontal Bridgman material, each fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch. The pixellated detectors were flip-chip-mounted side by side and read out by a 32-channel ASIC. This detector was also shielded by a passive/plastic collimator in the front, but used only additional passive/plastic shielding in the rear. Both experiments were flown from Ft. Sumner, NM on September 19, 2000 on a 24 hour balloon flight. CZT1 recorded a non-vetoed backgro...

  6. DUMAND detector

    CERN Multimedia

    This object is one of the 256 other detectors of the DUMAND (Deep Underwater Muon And Neutrino Detection) experiment. The goal of the experiment was the construction of the first deep ocean high energy neutrino detector, to be placed at 4800 m depth in the Pacific Ocean off Keahole Point on the Big Island of Hawaii. A few years ago, a European conference with Cosmic experiments was organized at CERN as they were projects like DUMAND in Hawaii. Along with the conference, a temporary exhibition was organised as well. It was a collaboration of institutions from Germany, Japan, Switzerland and the U.S.A. CERN had borrowed equipment and objects from different institutes around the world, including this detector of the DUMAND experiment. Most of the equipment were sent back to the institutes, however this detector sphere was offered to a CERN member of the personnel.

  7. Balloon flight background measurement with actively-shielded planar and imaging CZT detectors

    Science.gov (United States)

    Bloser, Peter F.; Narita, Tomohiko; Jenkins, Jonathan A.; Perrin, Marshall; Murray, Ruth; Grindlay, Jonathan E.

    2002-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as CZT1, consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator in the front, giving a 40 degree field of view and surrounded by plastic scintillator, and a thick BGO crystal in the rear. The second detector, CZT2, comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Products high pressure Bridgman material and the other of IMARAD horizontal Bridgman material, each fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch. The pixellated detectors were flip-chip-mounted side by side and read out by a 32-channel ASIC. This detector was also shielded by a passive/plastic collimator in the front, but used only additional passive/plastic shielding in the rear. Both experiments were flown from Ft. Sumner, NM on September 19, 2000 on a 24 hour balloon flight. Both instruments performed well. CZT1 recorded a non-vetoed background level at 100 keV of approximately 1 x 10-3 cm-2s-1keV-1. Raising the BGO threshold from 50 keV to approximately 1 MeV produced only an 18% increase in this level. CZT2 recorded a background at 100 keV of approximately 4 times 10-3 cts cm-2s-1keV-1 in the eV Products detector and approximately 6 x 10-3 cts cm-2s-1keV-1 in the IMARAD detector, a difference possibly due to our internal background subtracting procedure. Both CZT1 and CZT2 spectra were in basic agreement with Monte Carlo simulations, though both recorded systematically higher count rates at high energy than predicted. No lines were observed, indicating that neutron capture reactions, at least those producing decay lines at a few 100 keV, are not significant components of the CZT background. Comparison of the CZT1 and CZT2 spectra indicates that passive/plastic shielding may provide adequately low background levels for

  8. Calorimeter detectors

    CERN Document Server

    de Barbaro, P; The ATLAS collaboration

    2013-01-01

    Although the instantaneous and integrated luminosity in HL-LHC will be far higher than the LHC detectors were originally designed for, the Barrel calorimeters of the four experiments are expected to continue to perform well  throughout the Phase II program. The conditions for the End-Cap calorimeters are far more challenging and whilst some detectors will require relatively modest changes, others require far more substantial upgrades. We present the results of longevity and performance studies for the calorimeter systems of the four main LHC experiments and outline the upgrade options under consideration. We include a discussion of the R&D required to make the final technology choices for the upgraded detectors.

  9. Pixel detectors

    CERN Document Server

    Passmore, M S

    2001-01-01

    positions on the detector. The loss of secondary electrons follows the profile of the detector and increases with higher energy ions. studies of the spatial resolution predict a value of 5.3 lp/mm. The image noise in photon counting systems is investigated theoretically and experimentally and is shown to be given by Poisson statistics. The rate capability of the LAD1 was measured to be 250 kHz per pixel. Theoretical and experimental studies of the difference in contrast for ideal charge integrating and photon counting imaging systems were carried out. It is shown that the contrast differs and that for the conventional definition (contrast = (background - signal)/background) the photon counting device will, in some cases, always give a better contrast than the integrating system. Simulations in MEDICI are combined with analytical calculations to investigate charge collection efficiencies (CCE) in semiconductor detectors. Different pixel sizes and biasing conditions are considered. The results show charge shari...

  10. Assessment of array scintillation detector for follicle thyroid 2-D image acquisition using Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos Borges da; Santanna, Claudio Reis de [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)]. E-mails: borges@ien.gov.br; santanna@ien.gov.br; Braz, Delson [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Instrumentacao Nuclear]. E-mail: delson@lin.ufrj.br; Carvalho, Denise Pires de [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Biofisica Carlos Chagas Filho. Lab. de Fisiologia Endocrina]. E-mail: dencarv@ufrj.br

    2007-07-01

    This work presents an innovative study to find out the adequate scintillation inorganic detector array to be used coupled to a specific light photo sensor, a charge coupled device (CCD), through a fiber optic plate. The goal is to choose the type of detector that fits a 2-dimensional imaging acquisition of a cell thyroid tissue application with high resolution and detection efficiency in order to map a follicle image using gamma radiation emission. A point or volumetric source - detector simulation by using a MCNP4B general code, considering different source energies, detector materials and geometry including pixel sizes and reflector types was performed. In this study, simulations were performed for 7 x 7 and 127 x 127 arrays using CsI(Tl) and BGO scintillation crystals with pixel size ranging from 1 x 1 cm{sup 2} to 10 x 10 {mu}m{sup 2} and radiation thickness ranging from 1 mm to 10 mm. The effect of all these parameters was investigated to find the best source-detector system that result in an image with the best contrast details. The results showed that it is possible to design a specific imaging system that allows searching for in-vitro studies, specifically in radiobiology applied to endocrine physiology. (author)

  11. Hard X-ray Detector (HXD) on Board Suzaku

    CERN Document Server

    Takahashi, T; Endo, M; Endo, Y; Ezoe, Y; Fukazawa, Y; Hamaya, M; Hirakuri, S; Hong, S; Horii, M; Inoue, H; Isobe, N; Itoh, T; Iyomoto, N; Kamae, T; Kasama, D; Kataoka, J; Kato, H; Kawaharada, M; Kawano, N; Kawashima, K; Kawasoe, S; Kishishita, T; Kitaguchi, T; Kobayashi, Y; Kokubun, M; Kotoku, J; Kouda, M; Kubota, A; Kuroda, Y; Madejski, G; Makishima, K; Masukawa, K; Matsumoto, Y; Mitani, T; Miyawaki, R; Mizuno, T; Mori, K; Mori, M; Murashima, M; Murakami, T; Nakazawa, K; Niko, H; Nomachi, M; Okada, Y; Ohno, M; Oonuki, K; Ota, N; Ozawa, H; Sato, G; Shinoda, S; Sugiho, M; Suzuki, M; Taguchi, K; Takahashi, H; Takahashi, I; Takeda, S; Tamura, K; Tamura, T; Tanaka, T; Tanihata, C; Tashiro, M; Terada, Y; Tominaga, S; Uchiyama, Y; Watanabe, S; Yamaoka, K; Yanagida, T; Yonetoku, D

    2006-01-01

    The Hard X-ray Detector (HXD) on board Suzaku covers a wide energy range from 10 keV to 600 keV by combination of silicon PIN diodes and GSO scintillators. The HXD is designed to achieve an extremely low in-orbit back ground based on a combination of new techniques, including the concept of well-type active shield counter. With an effective area of 142 cm^2 at 20 keV and 273 cm2 at 150 keV, the background level at the sea level reached ~1x10^{-5} cts s^{-1} cm^{-2} keV^{-1} at 30 keV for the PI N diodes, and ~2x10^{-5} cts s^{-1} cm^{-2} keV^{-1} at 100 keV, and ~7x10^{-6} cts s^{-1} cm^{-2} keV^{-1} at 200 keV for the phoswich counter. Tight active shielding of the HXD results in a large array of guard counters surrounding the main detector parts. These anti-coincidence counters, made of ~4 cm thick BGO crystals, have a large effective area for sub-MeV to MeV gamma-rays. They work as an excellent gamma-ray burst monitor with limited angular resolution (~5 degree). The on-board signal-processing system and th...

  12. The Performance Test of Three Kinds of Detectors for PGNAA%瞬发伽玛活化分析中3种探测器性能比较

    Institute of Scientific and Technical Information of China (English)

    华龙; 肖才锦; 姚永刚; 金象春; 王平生; 王兴华; 倪邦发

    2016-01-01

    The prompt gamma neutron activation analysis ( PGNAA) has been carried out by using the thermal neutron beam from the horizontal neutron guide of China Advance Research Reactor (CARR).Three kinds of gamma detectors ( HPGe, BGO and LaBr 3 ) have been used for prompt gamma ray collection which came from the four kinds of specimen (NH4Cl, Si, Fe and Al).The capabilities of linearity, resolution and detection effi-ciency of gamma energy have been compared which are from the HPGe , BGO and LaBr 3 detectors respectively at the range of 2 keV to 10MeV of gamma energy .The results indicated that the detector of LaBr 3 is reasonable predominance of detection efficiency and resolution of gamma energy .%利用中国先进研究堆( CARR)热中子束流孔道首次开展了瞬发伽玛中子活化分析( PGNAA)实验。对NH4Cl、Si、Fe、Al等4种样品进行了辐照,同时采用HPGe、LaBr3、BGO 3种探测器对样品进行实时测量,在瞬发伽玛射线的能量为0.002~10 MeV范围内研究了3种探测器在宽能区的能量线性、能量分辨率、探测效率等性能。

  13. Development of a simple detector response function generation program: The CEARDRFs code

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jiaxin, E-mail: jwang3@ncsu.edu [Center for Engineering Applications of Radioisotopes (CEAR), Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Wang Zhijian; Peeples, Johanna [Center for Engineering Applications of Radioisotopes (CEAR), Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Yu Huawei [Center for Engineering Applications of Radioisotopes (CEAR), Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States); College of Geo-Resources and Information, China University of Petroleum, Qingdao, Shandong 266555 (China); Gardner, Robin P. [Center for Engineering Applications of Radioisotopes (CEAR), Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States)

    2012-07-15

    A simple Monte Carlo program named CEARDRFs has been developed to generate very accurate detector response functions (DRFs) for scintillation detectors. It utilizes relatively rigorous gamma-ray transport with simple electron transport, and accounts for two phenomena that have rarely been treated: scintillator non-linearity and the variable flat continuum part of the DRF. It has been proven that these physics and treatments work well for 3 Multiplication-Sign 3 Double-Prime and 6 Multiplication-Sign 6 Double-Prime cylindrical NaI detector in CEAR's previous work. Now this approach has been expanded to cover more scintillation detectors with various common shapes and sizes. Benchmark experiments of 2 Multiplication-Sign 2 Double-Prime cylindrical BGO detector and 2 Multiplication-Sign 4 Multiplication-Sign 16 Double-Prime rectangular NaI detector have been carried out at CEAR with various radiactive sources. The simulation results of CEARDRFs have also been compared with MCNP5 calculations. The benchmark and comparison show that CEARDRFs can generate very accurate DRFs (more accurate than MCNP5) at a very fast speed (hundred times faster than MCNP5). The use of this program can significantly increase the accuracy of applications relying on detector spectroscopy like prompt gamma-ray neutron activation analysis, X-ray fluorescence analysis, oil well logging and homeland security. - Highlights: Black-Right-Pointing-Pointer CEARDRF has been developed to generate detector response functions (DRFs) for scintillation detectors a. Black-Right-Pointing-Pointer Generated DRFs are very accurate. Black-Right-Pointing-Pointer Simulation speed is hundreds of times faster than MCNP5. Black-Right-Pointing-Pointer It utilizes rigorous gamma-ray transport with simple electron transport. Black-Right-Pointing-Pointer It also accounts for scintillator non-linearity and the variable flat continuum part.

  14. XMASS detector

    CERN Document Server

    Abe, K; Hiraide, K; Hirano, S; Kishimoto, Y; Kobayashi, K; Moriyama, S; Nakagawa, K; Nakahata, M; Nishiie, H; Ogawa, H; Oka, N; Sekiya, H; Shinozaki, A; Suzuki, Y; Takeda, A; Takachio, O; Ueshima, K; Umemoto, D; Yamashita, M; Yang, B S; Tasaka, S; Liu, J; Martens, K; Hosokawa, K; Miuchi, K; Murata, A; Onishi, Y; Otsuka, Y; Takeuchi, Y; Kim, Y H; Lee, K B; Lee, M K; Lee, J S; Fukuda, Y; Itow, Y; Nishitani, Y; Masuda, K; Takiya, H; Uchida, H; Kim, N Y; Kim, Y D; Kusaba, F; Motoki, D; Nishijima, K; Fujii, K; Murayama, I; Nakamura, S

    2013-01-01

    The XMASS project aims to detect dark matter, pp and $^{7}$Be solar neutrinos, and neutrinoless double beta decay using ultra pure liquid xenon. The first phase of the XMASS experiment searches for dark matter. In this paper, we describe the XMASS detector in detail, including its configuration, data acquisition equipment and calibration system.

  15. XMASS detector

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hieda, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Hiraide, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hirano, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kishimoto, Y.; Kobayashi, K.; Moriyama, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nakagawa, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Nakahata, M. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nishiie, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Ogawa, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); and others

    2013-07-11

    The XMASS project aims to detect dark matter, pp and {sup 7}Be solar neutrinos, and neutrinoless double beta decay using ultra pure liquid xenon. The first phase of the XMASS experiment searches for dark matter. In this paper, we describe the XMASS detector in detail, including its configuration, data acquisition equipment and calibration system.

  16. Measurement of the L/K electron capture ratio of the {sup 207}Bi decay to the 1633 keV level of {sup 207}Pb with a BGO scintillating bolometer

    Energy Technology Data Exchange (ETDEWEB)

    Coron, N.; Gironnet, J.; Marcillac, P. de; Martinez, M.; Redon, T.; Torres, L. [Universite Paris-Sud 11 et CNRS (UMR 8617), Institut d' Astrophysique Spatiale, Orsay (France); Cuesta, C.; Garcia, E.; Ginestra, C.; Ortigoza, Y.; Pobes, C.; Puimedon, J.; Salinas, A.; Sarsa, M.L. [Universidad de Zaragoza, Grupo de Fisica Nuclear y Astroparticulas, Zaragoza (Spain); Watrin, A. [Universidad de Zaragoza, Grupo de Fisica Nuclear y Astroparticulas, Zaragoza (Spain); Universite Louis Pasteur, Ecole nationale superieure de physique de Strasbourg (ENSPS), Illkirch (France)

    2012-06-15

    The ROSEBUD Collaboration has dedicated several underground runs to study different types of bolometers, mainly for the search of dark matter. Some of these runs, profiting from the good energy resolution of one bolometer of BGO and the ultra-low background of the underground laboratory of Canfranc (LSC), allowed the measurement of the L/K electron capture ratio of the {sup 207}Bi decay to the 1633 keV level of {sup 207}Pb. This paper constitutes the first published measurement of this magnitude. (orig.)

  17. The soft gamma-ray detector (SGD) onboard ASTRO-H

    Science.gov (United States)

    Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Blandford, Roger; Enoto, Teruaki; Goldwurm, Andrea; Hagino, Kouichi; Hayashi, Katsuhiro; Ichinohe, Yuto; Kataoka, Jun; Katsuta, Junichiro; Kitaguchi, Takao; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Grzegorz M.; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Nakano, Toshio; Nakazawa, Kazuhiro; Noda, Hirofumu; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shinya; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Tanaka, Yasuyuki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamaoka, Kazutaka; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

    2016-07-01

    The Soft Gamma-ray Detector (SGD) is one of science instruments onboard ASTRO-H (Hitomi) and features a wide energy band of 60{600 keV with low backgrounds. SGD is an instrument with a novel concept of "Narrow field-of-view" Compton camera where Compton kinematics is utilized to reject backgrounds which are inconsistent with the field-of-view defined by the active shield. After several years of developments, the flight hardware was fabricated and subjected to subsystem tests and satellite system tests. After a successful ASTRO-H (Hitomi) launch on February 17, 2016 and a critical phase operation of satellite and SGD in-orbit commissioning, the SGD operation was moved to the nominal observation mode on March 24, 2016. The Compton cameras and BGO-APD shields of SGD worked properly as designed. On March 25, 2016, the Crab nebula observation was performed, and, the observation data was successfully obtained.

  18. Application of multiparameter coincidence spectrometry using a Ge detectors array to neutron activation analysis

    CERN Document Server

    Hatsukawa, Y; Hayakawa, T; Toh, Y; Shinohara, N

    2002-01-01

    The method of multiparameter coincidence spectrometry based on gamma-gamma coincidence is widely used for the nuclear structure studies, because of its high sensitivity to gamma-rays. In this study, feasibility of the method of multiparameter coincidence spectrometry for analytical chemistry was examined. Two reference igneous rock samples (JP-1, JB-1a) issued by the Geological Survey of Japan were irradiated at a research reactor, and the gamma-rays from the radioisotopes produced via neutron capture reactions were measured using an array of 12 Ge detectors with BGO Compton suppressors, GEMINI. Simultaneously 24 elements were analyzed without chemical separation. The observed smallest component was Eu contained in JP-1 with abundance of 4 ppb.

  19. DUAL-BAND INFRARED DETECTORS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    As the infrared technology continues to advance, there is a growing demand for multispectral detectors for advanced IR systems with better target discrimination and identification. Both HgCdTe detectors and quantum well GaAs/AlGaAs photodetectors offer wavelength flexibility from medium wavelength to very long wavelength and multicolor capability in these regions. The main challenges facing all multicolor devices are more complicated device structtures, thicker and multilayer material growth, and more difficult device fabrication, especially when the array size gets larger and pixel size gets smaller. In the paper recent progress in development of two-color HgCdTe photodiodes and quantum well infrared photodetectors is presented.More attention is devoted to HgCdTe detectors. The two-color detector arrays are based upon an n-P-N (the capital letters mean the materials with larger bandgap energy) HgCdTe triple layer heterojunction design. Vertically stacking the two p-n junctions permits incorporation of both detectros into a single pixel. Both sequential mode and simultaneous mode detectors are fabricated. The mode of detection is determined by the fabrication process of the multilayer materials.Also the performances of stacked multicolor QWIPs detectors are presented. For multicolor arrays, QWIP's narrow band spectrum is an advantage, resulting in low spectral crosstalk. The major challenge for QWIP is developing broadband or multicolor optical coupling structures that permit efficient absorption of all required spectral bands.

  20. Semiconductor Detectors; Detectores de Semiconductores

    Energy Technology Data Exchange (ETDEWEB)

    Cortina, E.

    2007-07-01

    Particle detectors based on semiconductor materials are among the few devices used for particle detection that are available to the public at large. In fact we are surrounded by them in our daily lives: they are used in photoelectric cells for opening doors, in digital photographic and video camera, and in bar code readers at supermarket cash registers. (Author)

  1. A Study on Determination of an Optimized Detector for Single Photon Emission Computed Tomography.

    Science.gov (United States)

    Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Mohammad; Mahmoudian, Babak; Mardanshahi, Ali Reza

    2016-01-01

    The detector is a critical component of the single photon emission computed tomography (SPECT) imaging system for giving accurate information from the exact pattern of radionuclide distribution in the target organ. The SIMIND Monte Carlo program was utilized for the simulation of a Siemen's dual head variable angle SPECT imaging system with a low energy high resolution (LEHR) collimator. The Planar and SPECT scans for a (99m)Tc point source and a Jaszczak Phantom with the both experiment and simulated systems were prepared and after verification and validation of the simulated system, the similar scans of the phantoms were compared (from the point of view of the images' quality), namely, the simulated system with the detectors including bismuth germanate (BGO), yttrium aluminum garnet (YAG:Ce), Cerium-doped yttrium aluminum garnet (YAG:Ce), yttrium aluminum perovslite (YAP:Ce), lutetium aluminum garnet (LuAG:Ce), cerium activated lanthanum bromide (LaBr3), cadmium zinc telluride (CZT), and sodium iodide activated with thallium [NaI(Tl)]. The parameters of full width at half maximum (FWHM), energy and special resolution, sensitivity, and also the comparison of images' quality by the structural similarity (SSIM) algorithm with the Zhou Wang and Rouse/Hemami methods were analyzed. FWHMs for the crystals were calculated at 13.895, 14.321, 14.310, 14.322, 14.184, and 14.312 keV and the related energy resolutions obtained 9.854, 10.229, 10.221, 10.230, 10.131, and 10.223 %, respectively. Finally, SSIM indexes for comparison of the phantom images were calculated at 0.22172, 0.16326, 0.18135, 0.17301, 0.18412, and 0.20433 as compared to NaI(Tl). The results showed that BGO and LuAG: Ce crystals have high sensitivity and resolution, and better image quality as compared to other scintillation crystals.

  2. Graphene vertical hot-electron terahertz detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ryzhii, V., E-mail: v-ryzhii@riec.tohoku.ac.jp [Research Institute for Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Center for Photonics and Infrared Engineering, Bauman Moscow State Technical University and Institute of Ultra High Frequency Semiconductor Electronics, Russian Academy of Sciences, Moscow 111005 (Russian Federation); Satou, A.; Otsuji, T. [Research Institute for Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Ryzhii, M. [Department of Computer Science and Engineering, University of Aizu, Aizu-Wakamatsu 965-8580 (Japan); Mitin, V. [Department of Electrical Engineering, University at Buffalo, Buffalo, New York 1460-1920 (United States); Shur, M. S. [Departments of Electrical, Electronics, and Systems Engineering and Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2014-09-21

    We propose and analyze the concept of the vertical hot-electron terahertz (THz) graphene-layer detectors (GLDs) based on the double-GL and multiple-GL structures with the barrier layers made of materials with a moderate conduction band off-set (such as tungsten disulfide and related materials). The operation of these detectors is enabled by the thermionic emissions from the GLs enhanced by the electrons heated by incoming THz radiation. Hence, these detectors are the hot-electron bolometric detectors. The electron heating is primarily associated with the intraband absorption (the Drude absorption). In the frame of the developed model, we calculate the responsivity and detectivity as functions of the photon energy, GL doping, and the applied voltage for the GLDs with different number of GLs. The detectors based on the cascade multiple-GL structures can exhibit a substantial photoelectric gain resulting in the elevated responsivity and detectivity. The advantages of the THz detectors under consideration are associated with their high sensitivity to the normal incident radiation and efficient operation at room temperature at the low end of the THz frequency range. Such GLDs with a metal grating, supporting the excitation of plasma oscillations in the GL-structures by the incident THz radiation, can exhibit a strong resonant response at the frequencies of several THz (in the range, where the operation of the conventional detectors based on A{sub 3}B{sub 5} materials, in particular, THz quantum-well detectors, is hindered due to a strong optical phonon radiation absorption in such materials). We also evaluate the characteristics of GLDs in the mid- and far-infrared ranges where the electron heating is due to the interband absorption in GLs.

  3. How noise affects quantum detector tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q., E-mail: wang@physics.leidenuniv.nl; Renema, J. J.; Exter, M. P.van; Dood, M. J. A. de [Huygens Kamerlingh-Onnes Laboratory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden (Netherlands); Gaggero, A.; Mattioli, F.; Leoni, R. [Istituto di Fotonica e Nanotecnologie (IFN), CNR, via Cineto Romano 42, 00156 Roma (Italy)

    2015-10-07

    We determine the full photon number response of a NbN superconducting nanowire single photon detector via quantum detector tomography, and the results show the separation of linear, effective absorption efficiency from the internal detection efficiencies. In addition, we demonstrate an error budget for the complete quantum characterization of the detector. We find that for short times, the dominant noise source is shot noise, while laser power fluctuations limit the accuracy for longer timescales. The combined standard uncertainty of the internal detection efficiency derived from our measurements is about 2%.

  4. Comparative study of ionization chamber detectors vis-a-vis a CCD detector for dispersive XAS measurement in transmission geometry

    Energy Technology Data Exchange (ETDEWEB)

    Poswal, A. K.; Agrawal, A.; Bhattachryya, D.; Jha, S. N.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai -400 085 (India)

    2013-02-05

    We have designed and fabricated parallel plate ionization chamber detectors and voltage vs. current characteristics (V-I curve) of the detectors were recorded with synchrotron radiation to qualify for use in X-ray Absorption Spectroscopy (XAS) measurements. After qualifying the ionization chambers, the detectors were used in the dispersive EXAFS beamline (BL-08) at INDUS-2 SRS in Turbo-XAS geometry. Using the same setup and under the same setting, XAS spectra were also recorded with a CCD detector and the observation on relative performance of the ionization chamber vis-a-vis the CCD detector is presented in this paper.

  5. Absorption spectroscopy of EBT model GAFCHROMIC film.

    Science.gov (United States)

    Devic, Slobodan; Tomic, Nada; Pang, Zhiyu; Seuntjens, Jan; Podgorsak, Ervin B; Soares, Christopher G

    2007-01-01

    The introduction of radiochromic films has solved some of the problems associated with conventional 2D radiation detectors. Their high spatial resolution, low energy dependence, and near-tissue equivalence make them ideal for measurement of dose distributions in radiation fields with high dose gradients. Precise knowledge of the absorption spectra of these detectors can help to develop more suitable optical densitometers and potentially extend the use of these films to other areas such as the measurement of the radiation beam spectral information. The goal of this study is to present results of absorption spectra measurements for the new GAFCHROMIC film, EBT type, exposed to 6 MV photon beam in the dose range from 0 to 6 Gy. Spectroscopic analysis reveals that in addition to the two main absorption peaks, centered at around 583 and 635 nm, the absorption spectrum in the spectral range from 350 to 800 nm contains six more absorption bands. Comparison of the absorption spectra reveals that previous HD-810, MD-55, as well as HS GAFCHROMIC film models, have nearly the same sensitive layer base material, whereas the new EBT model, GAFCHROMIC film has a different composition of its sensitive layer. We have found that the two most prominent absorption bands in EBT model radiochromic film do not change their central wavelength position with change in a dose deposited to the film samples.

  6. Et. réact. $e^{+} e^{-} \\to e^{+} e^{-} \\gamma$, $e^{+} e^{-} \\to e^{+} e^{-} e^{+} e^{-}$ et $e^{+} e^{-} \\to e^{+} e ^{-} \\mu^{+} \\mu^{-}$ pour la calibrat. cristaux BGO calorim. électromagn. L3,, CERN, mesure luminosité LEP

    CERN Document Server

    Rayo, F

    1989-01-01

    Et. réact. $e^{+} e^{-} \\to e^{+} e^{-} \\gamma$, $e^{+} e^{-} \\to e^{+} e^{-} e^{+} e^{-}$ et $e^{+} e^{-} \\to e^{+} e ^{-} \\mu^{+} \\mu^{-}$ pour la calibrat. cristaux BGO calorim. électromagn. L3,, CERN, mesure luminosité LEP

  7. Radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, Rusi P.

    2017-06-27

    Alpha particle detecting devices are disclosed that have a chamber that can hold a fluid in a tensioned metastable state. The chamber is tuned with a suitable fluid and tension such that alpha emitting materials such as radon and one or more of its decay products can be detected. The devices can be portable and can be placed in areas, such as rooms in dwellings or laboratories and used to measure radon in these areas, in situ and in real time. The disclosed detectors can detect radon at and below 4 pCi/L in air; also, at and below 4,000 pCi/L or 300 pCi/L in water.

  8. The physics of nanowire superconducting single-photon detectors

    NARCIS (Netherlands)

    Renema, Jelmer Jan

    2015-01-01

    We investigate the detection mechanism in superconducting single photon detectors via quantum detector tomography. We find that the detection event is caused by diffusion of quasiparticles from the absorption spot, combined with entrance of a vortex. Moreover, we investigate the behaviour of

  9. Neutron responsive self-powered radiation detector

    Science.gov (United States)

    Brown, Donald P.; Cannon, Collins P.

    1978-01-01

    An improved neutron responsive self-powered radiation detector is disclosed in which the neutron absorptive central emitter has a substantially neutron transmissive conductor collector sheath spaced about the emitter and the space between the emitter and collector sheath is evacuated.

  10. Solid-State Neutron Detector Device

    Science.gov (United States)

    Bensaoula, Abdelhak (Inventor); Starikov, David (Inventor); Pillai, Rajeev (Inventor)

    2017-01-01

    The structure and methods of fabricating a high efficiency compact solid state neutron detector based on III-Nitride semiconductor structures deposited on a substrate. The operation of the device is based on absorption of neutrons, which results in generation of free carriers.

  11. Measurement of 15 MeV gamma-rays with the Ge cluster detectors of EUROBALL

    CERN Document Server

    Million, B; Camera, F; Brambilla, S; Gadea, A; Giugni, D; Herskind, B; Kmiecik, M; Isocrate, R; Leoni, S; Maj, A; Prelz, F; Wieland, O

    2000-01-01

    A measurement of the response to 15.1 MeV gamma-rays has been made for the Ge cluster detectors in the EUROBALL array. Each cluster detector consists of seven germanium capsules surrounded by a single anticompton shield of BGO. The reaction D( sup 1 sup 1 B,gamma) sup 1 sup 2 C+n at E sub b sub e sub a sub m =19.1 MeV has been employed. The 'adding-back' of signals simultaneously present in the capsules composing each cluster detector has been made on an event by event basis. The intensity in full-energy peak increases by a factor of three as compared to that of the spectrum obtained by summing the individual spectra of the 7 capsules. The pulse height to energy conversion is found to be very linear from few hundreds keV to 15 MeV. The efficiency is discussed relative to that of large volume BaF sub 2 scintillators.

  12. PHAROS A pluri-detector, high-resolution, analyser of radiometric properties of soil

    CERN Document Server

    Rigollet, C

    2002-01-01

    PHAROS is a new type of core logger, designed to measure activity concentrations of sup 4 sup 0 K, sup 2 sup 3 sup 8 U, sup 2 sup 3 sup 2 Th and sup 1 sup 3 sup 7 Cs in sediment and rock cores with a spatial resolution of a few centimetres along the core. PHAROS has been developed as a non-destructive alternative to the traditional slicing of cores into sub-samples and their analysis on an HPGe detector. The core is scanned at fixed increments by three BGO scintillation detectors and the spectra analysed by the full spectrum analysis method. The core logger is also equipped with a collimated lead castle and a sup 1 sup 3 sup 7 Cs source for transmission measurements. In this paper, we report on the properties of the core logger and its detectors, and on the analysis techniques used for the determination of the radionuclides activity concentrations. Results from initial measurements are presented and discussed.

  13. CLIC Detector Power Requirements

    CERN Document Server

    Gaddi, A

    2013-01-01

    An estimate for the CLIC detector power requirements is outlined starting from the available data on power consumptions of the four LHC experiments and considering the differences between a typical LHC Detector (CMS) and the CLIC baseline detector concept. In particular the impact of the power pulsing scheme for the CLIC Detector electronics on the overall detector consumption is considered. The document will be updated with the requirements of the sub-detector electronics once they are more defined.

  14. Pixel Vertex Detectors

    OpenAIRE

    Wermes, Norbert

    2006-01-01

    Pixel vertex detectors are THE instrument of choice for the tracking of charged particles close to the interaction point at the LHC. Hybrid pixel detectors, in which sensor and read-out IC are separate entities, constitute the present state of the art in detector technology. Three of the LHC detectors use vertex detectors based on this technology. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as ...

  15. Determination of the total absorption peak in an electromagnetic calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jia-Hua [Institute of Physics, National Chiao-Tung University, Hsinchu (China); Wang, Zhe, E-mail: wangzhe-hep@mail.tsinghua.edu.cn [Department of Engineering Physics, Tsinghua University, Beijing (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Lebanowski, Logan [Department of Engineering Physics, Tsinghua University, Beijing (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Lin, Guey-Lin [Institute of Physics, National Chiao-Tung University, Hsinchu (China); Chen, Shaomin [Department of Engineering Physics, Tsinghua University, Beijing (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China)

    2016-08-11

    A physically motivated function was developed to accurately determine the total absorption peak in an electromagnetic calorimeter and to overcome biases present in many commonly used methods. The function is the convolution of a detector resolution function with the sum of a delta function, which represents the complete absorption of energy, and a tail function, which describes the partial absorption of energy and depends on the detector materials and structures. Its performance was tested with the simulation of three typical cases. The accuracy of the extracted peak value, resolution, and peak area was improved by an order of magnitude on average, relative to the Crystal Ball function.

  16. Determination of the total absorption peak in an electromagnetic calorimeter

    CERN Document Server

    Cheng, Jia-Hua; Lebanowski, Logan; Lin, Guey-Lin; Chen, Shaomin

    2016-01-01

    A physically-motivated function was developed to accurately determine the total absorption peak in an electromagnetic calorimeter and to overcome biases present in many commonly used methods. The function is the convolution of a detector resolution function with the sum of a delta function, which represents the complete absorption of energy, and a tail function, which describes the partial absorption of energy and depends on the detector materials and structures. Its performance was tested with the simulation of three typical cases. The accuracy of the extracted peak value, resolution, and peak area was improved by an order of magnitude on average, relative to the Crystal Ball function.

  17. MUON DETECTOR

    CERN Multimedia

    F. Gasparini

    DT As announced in the previous Bulletin MU DT completed the installation of the vertical chambers of barrel wheels 0, +1 and +2. 242 DT and RPC stations are now installed in the negative barrel wheels. The missing 8 (4 in YB-1 and 4 in YB-2) chambers can be installed only after the lowering of the two wheels into the UX cavern, which is planned for the last quarter of the year. Cabling on the surface of the negative wheels was finished in May after some difficulties with RPC cables. The next step was to begin the final commissioning of the wheels with the final trigger and readout electronics. Priority was giv¬en to YB0 in order to check everything before the chambers were covered by cables and services of the inner detectors. Commissioning is not easy since it requires both activity on the central and positive wheels underground, as well as on the negative wheels still on the surface. The DT community is requested to commission the negative wheels on surface to cope with a possible lack of time a...

  18. Development of a High Dynamic Range Read-out System Using Multi-photodiode for the Total Absorption Calorimeter of CALET

    Science.gov (United States)

    Katayose, Y.; Shibata, M.; Torii, S.; Shimizu, Y.; Tamura, T.; Hibino, K.; Okuno, S.; Yoshida, K.; Kitamura, H.; Uchihori, Y.; Murakami, H.

    We have been developing the CALET instrument, which is proposed to be launched on the Japanese Experiment Module (JEM), Exposed Facility (EF) of the ISS. CALET consists of an imaging calorimeter (IMC) and a total absorption calorimeter (TASC). The role of IMC is identification of the incident particle by imaging the shower tracks with scintillating fibers. TASC is used for observing the total development of shower particles with a stack of BGO scintillators. A read-out system using multi-photodiode and a front-end circuit including analog ASIC, 16 bit ADC, FPGA was developed to measure the energy deposit with the dynamic range from 1MIP(Minimum Ionization Particle) up to 106MIPs in a BGO bar of TASC. The output signal of 1 MIP was calibrated by cosmic ray muon. The dynamic range of the read-out system was measured with both LED pulser and heavy ions beam in the range from 1MIP to about 2400 MIPs . In this paper, the performance of the read-out system is described.

  19. A novel depth-of-interaction block detector for positron emission tomography using a dichotomous orthogonal symmetry decoding concept

    Science.gov (United States)

    Zhang, Yuxuan; Yan, Han; Baghaei, Hossain; Wong, Wai-Hoi

    2016-02-01

    Conventionally, a dual-end depth-of-interaction (DOI) block detector readout requires two two-dimensional silicon photomultiplier (SiPM) arrays, one on top and one on the bottom, to define the XYZ positions. However, because both the top and bottom SiPM arrays are reading the same pixels, this creates information redundancy. We propose a dichotomous orthogonal symmetric (DOS) dual-end readout block detector design, which removes this redundancy by reducing the number of SiPMs and still achieves XY and DOI (Z) decoding for positron emission tomography (PET) block detector. Reflecting films are used within the block detector to channel photons going to the top of the block to go only in the X direction, and photons going to the bottom are channeled along the Y direction. Despite the unidirectional channeling on each end, the top readout provides both X and Y information using two one-dimensional SiPM arrays instead of a two-dimensional SiPM array; similarly, the bottom readout also provides both X and Y information with just two one-dimensional SiPM arrays. Thus, a total of four one-dimensional SiPM arrays (4  ×  N SiPMs) are used to decode the XYZ positions of the firing pixels instead of two two-dimensional SiPM arrays (2  ×  N  ×  N SiPMs), reducing the number of SiPM arrays per block from 2N2 to 4 N for PET/MR or PET/CT systems. Moreover, the SiPM arrays on one end can be replaced by two regular photomultiplier tubes (PMTs), so that a block needs only 2 N SiPMs  +  2 half-PMTs; this hybrid-DOS DOI block detector can be used in PET/CT systems. Monte Carlo simulations were carried out to study the performance of our DOS DOI block detector design, including the XY-decoding quality, energy resolution, and DOI resolution. Both BGO and LSO scintillators were studied. We found that 4 mm pixels were well decoded for 5  ×  5 BGO and 9  ×  9 LSO arrays with 4 to 5 mm DOI resolution and 16-20% energy resolution. By

  20. A multi-panel direction-sensitive gamma-ray detector for low-altitude radiological searches

    Science.gov (United States)

    Becker, E. M.; Farsoni, A. T.

    2016-11-01

    A lightweight, low-cost multi-panel direction-sensitive radiation detector prototype has been developed at Oregon State University that is designed to be mounted on a small unmanned aerial system to autonomously search for radiation sources while flying close to the ground. The detection system comprises sixteen BGO-SiPM detector panels with an adjustable view angle, and signal outputs are processed in parallel in an FPGA. The minimum detectable activity was calculated to be 1.3 μCi of 137Cs at 1 m in under 60 s. The counting response of the detector panels were characterized and found to have 4.7% relative standard deviation, indicating good uniformity in overall design and assembly. The detector was also able to estimate the direction of a 12.3 μCi 137Cs source 100 cm from the device center with 2.3° accuracy in a 95% confidence width of 10.8° in 60 s.

  1. Plasmonic lens enhanced mid-infrared quantum cascade detector

    Energy Technology Data Exchange (ETDEWEB)

    Harrer, Andreas, E-mail: andreas.harrer@tuwien.ac.at; Schwarz, Benedikt; Gansch, Roman; Reininger, Peter; Detz, Hermann; Zederbauer, Tobias; Andrews, Aaron Maxwell; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, 1040 Vienna (Austria)

    2014-10-27

    We demonstrate monolithic integrated quantum cascade detectors enhanced by plasmonic lenses. Surface normal incident mid-infrared radiation is coupled to surface plasmon polaritons guided to and detected by the active region of the detector. The lens extends the optical effective active area of the device up to a 5 times larger area than for standard mesa detectors or pixel devices while the electrical active region stays the same. The extended optical area increases the absorption efficiency of the presented device as well as the room temperature performance while it offers a flexible platform for various detector geometries. A photocurrent response increase at room temperature up to a factor of 6 was observed.

  2. The MINOS Detectors

    CERN Document Server

    Grashorn, A H E W

    2005-01-01

    The Main Injector Neutrino Oscillation Search (MINOS) experiment's primary goal is the precision measurement of the neutrino oscillation parameters in the atmospheric neutrino sector. This long-baseline experiment uses Fermilab's NuMI beam, measured with a Near Detector at Fermilab, and again 735 km later using a Far Detector in the Soudan Mine Underground Lab in northern Minnesota. The detectors are magnetized iron/scintillator calorimeters. The Far Detector has been operational for cosmic ray and atmospheric neutrino data from July of 2003, the Near Detector from September 2004, and the NuMI beam started in early 2005. This poster presents details of the two detectors.

  3. GADRAS Detector Response Function.

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Dean J.; Harding, Lee; Thoreson, Gregory G; Horne, Steven M.

    2014-11-01

    The Gamma Detector Response and Analysis Software (GADRAS) applies a Detector Response Function (DRF) to compute the output of gamma-ray and neutron detectors when they are exposed to radiation sources. The DRF is fundamental to the ability to perform forward calculations (i.e., computation of the response of a detector to a known source), as well as the ability to analyze spectra to deduce the types and quantities of radioactive material to which the detectors are exposed. This document describes how gamma-ray spectra are computed and the significance of response function parameters that define characteristics of particular detectors.

  4. The TALE Tower Detector

    Science.gov (United States)

    Bergman, D. R.

    The TA Low Energy Extension will include a Tower FluorescenceDetector. Extensive air showers at the lowest usful energies for fluorescence detectors will in general be close to the detector. This requires viewing all elevation angles to be able to reconstruct showers. The TALE Tower Detector, operating in conjunction with other TALE detectors will view elevation angles up to above 70 degrees, with an azimuthal coverage of about 90 degrees. Results from a prototype mirror operated in conjunction with the HiRes detector will also be presented.

  5. Atmospheric Neutron Measurements using a Small Scintillator Based Detector

    Science.gov (United States)

    Kole, Merlin; Pearce, Mark; Fukazawa, Yasushi; Fukuda, Kentaro; Ishizu, Sumito; Jackson, Miranda; Kamae, Tune; Kawaguchi, Noriaki; Kawano, Takafumi; Kiss, Mozsi; Moretti, Elena; Yanagida, Takayuki; Chauvin, Maxime; Mikhalev, Victor; Rydstrom, Stefan; Takahashi, Hiromitsu

    PoGOLino is a standalone scintillator-based neutron detector designed for balloon-borne missions. Its main purpose is to provide data of the neutron flux in 2 different energy ranges in the high altitude / high latitude region where the highest neutron flux in the atmosphere is found. Furthermore the influence of the Solar activity upon the neutron environment in this region is relatively strong. As a result both short and long term time fluctuations are strongest in this region. At high altitudes neutrons can form a source of background for balloon-borne scientific measurements. They can furthermore form a major source for single event upsets in electronics. A good understanding of the high altitude / high latitude neutron environment is therefore important. Measurements of the neutron environment in this region are however lacking. PoGOLino contains two 5 mm thick Lithium Calcium Aluminium Fluoride (LiCAF) scintillators used for neutron detection. The LiCAF crystals are sandwiched between 2 Bismuth Germanium Oxide (BGO) scintillating crystals, which serve to veto signals produced by gamma-rays and charged particles. The veto system makes measurements of the neutron flux possible even in high radiation environments. One LiCAF detector is shielded with polyethylene while the second remains unshielded, making the detectors sensitive in different energy ranges. The choice of a scintillator crystals as the detection material ensures a high detection efficiency while keeping the instrument small, robust and light weight. The full standalone cylindrical instrument has a radius of 120 mm, a height of 670 mm and a total mass of 13 kg, making it suitable as a piggy back mission. PoGOLino was successfully launched on March 20th 2013 from the Esrange Space Center in Northern Sweden to an altitude of 30.9 km. A detailed description of the detector design is presented, along with results of of the flight. The neutron flux measured during flight is compared to predictions based

  6. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I.; Martinez laso, L.

    1989-07-01

    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs.

  7. Superconducting nanowire single-photon detectors (SNSPDs) on SOI for near-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Trojan, Philipp; Il' in, Konstantin; Henrich, Dagmar; Hofherr, Matthias; Doerner, Steffen; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme (IMS), Karlsruher Institut fuer Technologie (KIT) (Germany); Semenov, Alexey [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Huebers, Heinz-Wilhelm [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin (Germany)

    2013-07-01

    Superconducting nanowire single-photon detectors are promising devices for photon detectors with high count rates, low dark count rates and low dead times. At wavelengths beyond the visible range, the detection efficiency of today's SNSPDs drops significantly. Moreover, the low absorption in ultra-thin detector films is a limiting factor over the entire spectral range. Solving this problem requires approaches for an enhancement of the absorption range in feeding the light to the detector element. A possibility to obtain a better absorption is the use of multilayer substrate materials for photonic waveguide structures. We present results on development of superconducting nanowire single-photon detectors made from niobium nitride on silicon-on-insulator (SOI) multilayer substrates. Optical and superconducting properties of SNSPDs on SOI will be discussed and compared with the characteristics of detectors on common substrates.

  8. Development of mercuric iodide detectors for XAS and XRD measurements

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, W.K.; Iwanczyk, J.S.; Dabrowski, A.J.; Hedman, B.; Penner-Hakn, J.E.; Roe, A.L.; Hodgson, K.O.; Beyerle, A.

    1985-07-01

    A prototype element for an energy dispersive detector (EDD) array was constructed using a Mercuric Iodide detector. Both detector and front end FET could be thermoelectrically cooled. Tested at SSRL, the detector had 250 eV electronic noise and 315 eV resolution at 5.9 keV. K line fluorescence spectra were collected for selected elements between Cl (2622 eV) and Zn (8638 eV). Count rate capability to 60,000 cps was demonstrated. Several detector parameters were measured, including energy linearity, resolution vs. shaping time, and detector dead time. An EXAFS (extended x-ray absorption fine structure) spectrum was recorded and compared to simultaneously collected transmission data.

  9. An optimized ultrasound detector for photoacoustic breast tomography

    CERN Document Server

    Xia, Wenfeng; Van Hespen, Johan; Van Veldhoven, Spiridon; Prins, Christian; Van Leeuwen, Ton; Steenbergen, Wiendelt; Manohar, Srirang

    2012-01-01

    Photoacoustic imaging has proven to be able to detect vascularization-driven optical absorption contrast associated with tumors. In order to detect breast tumors located a few centimeter deep in tissue, a sensitive ultrasound detector is of crucial importance for photoacoustic mammography. Further, because the expected photoacoustic frequency bandwidth (a few MHz to tens of kHz) is inversely proportional to the dimensions of light absorbing structures (0.5 to 10+ mm), proper choices of materials and their geometries, and proper considerations in design have to be made for optimal photoacoustic detectors. In this study, we design and evaluate a specialized ultrasound detector for photoacoustic mammography. Based on the required detector sensitivity and its frequency response, a selection of active material and matching layers and their geometries is made leading to a functional detector models. By iteration between simulation of detector performances, fabrication and experimental characterization of functional...

  10. ASTRO-H CdTe detectors proton irradiation at PIF

    Energy Technology Data Exchange (ETDEWEB)

    Limousin, O.; Renaud, D.; Horeau, B.; Dubos, S. [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Laurent, P.; Lebrun, F. [APC Laboratory, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13 (France); Chipaux, R. [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Boatella Polo, C. [European Space Agency, ESTEC, Keplerlaan 1, NL-2201 AZ, Noordwijk (Netherlands); Marcinkowski, R. [Paul Scherrer Institute (PSI), Proton Irradiation Facility at Laboratory for Particle Physics, 5232 Villigen (Switzerland); Kawaharada, M.; Watanabe, S.; Ohta, M.; Sato, G.; Takahashi, T. [Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa, 252-5210 (Japan)

    2015-07-01

    Asbstract: The French Atomic Energy Commission (CEA), with the support of the European Space Agency (ESA), is partner of the Soft Gamma-Ray Detector (SGD) and the Hard X-ray Imager (HXI) onboard the 6th Japanese X-ray scientific satellite ASTRO-H (JAXA) initiated by the Institute of Space and Astronautical Science (ISAS). Both scientific instruments, one hosting a series of Compton Gamma Cameras and the other being a focal plane of a grazing incidence mirror telescope in the hard X-ray domain, are equipped with Cadmium Telluride based detectors. ASTRO-H will be operated in a Low Earth Orbit with a 31° inclination at ~550 km altitude, thus passing daily through the South Atlantic Anomaly radiation belt, a specially harsh environment where the detectors are suffering the effect of the interaction with trapped high energy protons. As CdTe detector performance might be affected by the irradiation, we investigate the effect of the accumulated proton fluence on their spectral response. To do so, we have characterized and irradiated representative samples of SGD and HXI detector under different conditions. The detectors in question, from ACRORAD, are single-pixels having a size of 2 mm by 2 mm and 750 µm thick. The Schottky contact is either made of an Indium or Aluminum for SGD and HXI respectively. We ran the irradiation test campaign at the Proton Irradiation Facility (PIF) at PSI, and ESA approved equipment to evaluate the radiation hardness of flight hardware. We simulated the proton flux expected on the sensors over the entire mission, and secondary neutrons flux due to primary proton interactions into the surrounding BGO active shielding. We eventually characterized the detector response evolution, emphasizing each detector spectral response as well as its stability by studying the so-called Polarization effect. The latter is provoking a spectral response degradation against time as a charge accumulation process occurs in Schottky type CdTe sensors. In this paper

  11. Thermal kinetic inductance detector

    Energy Technology Data Exchange (ETDEWEB)

    Cecil, Thomas; Gades, Lisa; Miceli, Antonio; Quaranta, Orlando

    2016-12-20

    A microcalorimeter for radiation detection that uses superconducting kinetic inductance resonators as the thermometers. The detector is frequency-multiplexed which enables detector systems with a large number of pixels.

  12. Forward tracking detectors

    Indian Academy of Sciences (India)

    Klaus Mönig

    2007-11-01

    Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  13. The OSMOND detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Dalgliesh, R. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.uk [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Holt, S.A.; Kinane, C.J. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Spill, E.J.; Stephenson, R. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom)

    2013-01-11

    The development and testing of the Off Specular MicrOstrip Neutron Detector (OSMOND) is described. Based on a microstrip gas chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing rate limited scintillator detectors currently in use on the CRISP reflectometer for off specular reflectometry experiments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  14. Energy-based scatter correction for 3-D PET scanners using NaI(T1) detectors.

    Science.gov (United States)

    Adam, L E; Karp, J S; Freifelder, R

    2000-05-01

    Earlier investigations with BGO positron emission tomography (PET) scanners showed that the scatter correction technique based on multiple acquisitions with different energy windows are problematic to implement because of the poor energy resolution of BGO (22%), particularly for whole-body studies. We believe that these methods are likely to work better with NaI(TI) because of the better energy resolution achievable with NaI(TI) detectors (10%). Therefore, we investigate two different choices for the energy window, a low-energy window (LEW) on the Compton spectrum at 400-450 keV, and a high-energy window (HEW) within the photopeak (lower threshold above 511 keV). The results obtained for our three-dimensional (3-D) (septa-less) whole-body scanners [axial field of view (FOV) of 12.8 cm and 25.6 cm] as well as for our 3-D brain scanner (axial FOV of 25.6 cm) show an accurate prediction of the scatter distribution for the estimation of trues method (ETM) using a HEW, leading to a significant reduction of the scatter contamination. The dual-energy window (DEW) technique using a LEW is shown to be intrinsically wrong; in particular, it fails for line source and bar phantom measurements. However, the method is able to produce good results for homogeneous activity distributions. Both methods are easy to implement, are fast, have a low noise propagation, and will be applicable to other PET scanners with good energy resolution and stability, such as hybrid NaI(TI) PET/SPECT dual-head cameras and future PET cameras with GSO or LSO scintillators.

  15. The CAPRICE RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Codino, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata` Rome (Italy); Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.; Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy)

    1995-09-01

    A compact RICH detector has been developed and used for particle identification in a balloon borne spectrometer to measure the flux of antimatter in the cosmic radiation. This is the first RICH detector ever used in space experiments that is capable of detecting unit charged particles, such as antiprotons. The RICH and all other detectors performed well during the 27 hours long flight.

  16. D-xylose absorption

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003606.htm D-xylose absorption To use the sharing features on this page, please enable JavaScript. D-xylose absorption is a laboratory test to determine ...

  17. Equalized near maximum likelihood detector

    OpenAIRE

    2012-01-01

    This paper presents new detector that is used to mitigate intersymbol interference introduced by bandlimited channels. This detector is named equalized near maximum likelihood detector which combines nonlinear equalizer and near maximum likelihood detector. Simulation results show that the performance of equalized near maximum likelihood detector is better than the performance of nonlinear equalizer but worse than near maximum likelihood detector.

  18. Vacuum ultraviolet detector for gas chromatography.

    Science.gov (United States)

    Schug, Kevin A; Sawicki, Ian; Carlton, Doug D; Fan, Hui; McNair, Harold M; Nimmo, John P; Kroll, Peter; Smuts, Jonathan; Walsh, Phillip; Harrison, Dale

    2014-08-19

    Analytical performance characteristics of a new vacuum ultraviolet (VUV) detector for gas chromatography (GC) are reported. GC-VUV was applied to hydrocarbons, fixed gases, polyaromatic hydrocarbons, fatty acids, pesticides, drugs, and estrogens. Applications were chosen to feature the sensitivity and universal detection capabilities of the VUV detector, especially for cases where mass spectrometry performance has been limited. Virtually all chemical species absorb and have unique gas phase absorption cross sections in the approximately 120-240 nm wavelength range monitored. Spectra are presented, along with the ability to use software for deconvolution of overlapping signals. Some comparisons with experimental synchrotron data and computed theoretical spectra show good agreement, although more work is needed on appropriate computational methods to match the simultaneous broadband electronic and vibronic excitation initiated by the deuterium lamp. Quantitative analysis is governed by Beer-Lambert Law relationships. Mass on-column detection limits reported for representatives of different classes of analytes ranged from 15 (benzene) to 246 pg (water). Linear range measured at peak absorption for benzene was 3-4 orders of magnitude. Importantly, where absorption cross sections are known for analytes, the VUV detector is capable of absolute determination (without calibration) of the number of molecules present in the flow cell in the absence of chemical interferences. This study sets the stage for application of GC-VUV technology across a wide breadth of research areas.

  19. High-energy detector

    Science.gov (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  20. Radiative Processes of the DeWitt-Takagi Detector

    CERN Document Server

    Díaz, D E

    2003-01-01

    We examine the excitation of a uniformly accelerated DeWitt-Takagi detector coupled quadratically to a Majorana-Dirac field. We obtain the transition probability from the ground state of the detector and the vacuum state of the field to an excited state with the emission of a Minkowski pair of quanta, in terms of elementary processes of absorption and scattering of Rindler quanta from the Fulling-Davies-Unruh thermal bath in the co-accelerated frame.

  1. The DØ detector

    Science.gov (United States)

    Abachi, S.; Abolins, M.; Acharya, B. S.; Adam, I.; Ahn, S.; Aihara, H.; Alvarez, G.; Alves, G. A.; Amos, N.; Anderson, W.; Antipov, Yu.; Aronson, S. H.; Astur, R.; Avery, R. E.; Baden, A.; Balderston, J.; Baldin, B.; Bantly, J.; Barasch, E.; Bartlett, J. F.; Bazizi, K.; Behnke, T.; Bezzubov, V.; Bhat, P. C.; Blazey, G.; Blessing, S.; Boehnlein, A.; Borcherding, F.; Borders, J.; Bozko, N.; Brandt, A.; Brock, R.; Bross, A.; Buchholz, D.; Burtovoy, V.; Butler, J. M.; Callot, O.; Chakraborty, D.; Chekulaev, S.; Chen, J.; Chen, L.-P.; Chen, W.; Choudhary, B. C.; Christenson, J. H.; Claes, D.; Clark, A. R.; Cobau, W. G.; Cochran, J.; Cooper, W. E.; Cretsinger, C.; Cullen-Vidal, D.; Cummings, M.; Cutts, D.; Dahl, O. I.; Daniels, B.; De, K.; Demarteau, M.; Denisenko, K.; Denisenko, N.; Denisov, D.; Denisov, S.; Dharmaratna, W.; Diehl, H. T.; Diesburg, M.; Dixon, R.; Draper, P.; Ducros, Y.; Durston-Johnson, S.; Eartly, D.; Eberhard, P. H.; Edmunds, D.; Efimov, A.; Ellison, J.; Elvira, V. D.; Engelmann, R.; Eroshin, O.; Evdokimov, V.; Fahey, S.; Fanourakis, G.; Fatyga, M.; Featherly, J.; Feher, S.; Fein, D.; Ferbel, T.; Finley, D.; Finocchiaro, G.; Fisk, H. E.; Flattum, E.; Forden, G. E.; Fortner, M.; Franzini, P.; Fuess, S.; Gallas, E.; Gao, C. S.; Geld, T. L.; Genser, K.; Gerber, C. E.; Gibbard, B.; Glebov, V.; Glicenstein, J. F.; Gobbi, B.; Goforth, M.; Good, M. L.; Goozen, F.; Gordon, H.; Graf, N.; Grannis, P. D.; Green, D. R.; Green, J.; Greenlee, H.; Grossman, N.; Grudberg, P.; Guida, J. A.; Guida, J. M.; Guryn, W.; Hadley, N. J.; Haggerty, H.; Hagopian, S.; Hagopian, V.; Hall, R. E.; Hansen, S.; Hauptman, J.; Hedin, D.; Heinson, A. P.; Heintz, U.; Heuring, T.; Hirosky, R.; Hodel, K.; Hoftun, J. S.; Hubbard, J. R.; Huehn, T.; Huson, R.; Igarashi, S.; Ito, A. S.; James, E.; Jiang, J.; Johns, K.; Johnson, C. R.; Johnson, M.; Jonckheere, A.; Jones, M.; Jöstlein, H.; Jung, C. K.; Kahn, S.; Kanekal, S.; Kernan, A.; Kerth, L.; Kirunin, A.; Klatchko, A.; Klima, B.; Klochkov, B.; Klopfenstein, C.; Klyukhin, V.; Kochetkov, V.; Kohli, J. M.; Kononenko, W.; Kotcher, J.; Kotov, I.; Kourlas, J.; Kozelov, A.; Kozlovsky, E.; Krafczyk, G.; Krempetz, K.; Krishnaswamy, M. R.; Kroon, P.; Krzywdzinski, S.; Kunori, S.; Lami, S.; Landsberg, G.; Lanou, R. E.; Laurens, P.; Lee-Franzini, J.; Li, J.; Li, R.; Li-Demarteau, Q. Z.; Lima, J. G. R.; Linn, S. L.; Linnemann, J.; Lipton, R.; Liu, Y.-C.; Lloyd-Owen, D.; Lobkowicz, F.; Loken, S. C.; Lokos, S.; Lueking, L.; Maciel, A. K. A.; Madaras, R. J.; Madden, R.; Malamud, E.; Mangeot, Ph.; Manning, I.; Mansoulié, B.; Manzella, V.; Mao, H.-S.; Marcin, M.; Markosky, L.; Marshall, T.; Martin, H. J.; Martin, M. I.; Martin, P. S.; Marx, M.; May, B.; Mayorov, A.; McCarthy, R.; McKinley, J.; Mendoza, D.; Meng, X.-C.; Merritt, K. W.; Milder, A.; Mincer, A.; Mondal, N. K.; Montag, M.; Mooney, P.; Mudan, M.; Mulholland, G. T.; Murphy, C.; Murphy, C. T.; Nang, F.; Narain, M.; Narasimham, V. S.; Neal, H. A.; Nemethy, P.; Nešić, D.; Ng, K. K.; Norman, D.; Oesch, L.; Oguri, V.; Oltman, E.; Oshima, N.; Owen, D.; Pang, M.; Para, A.; Park, C. H.; Partridge, R.; Paterno, M.; Peryshkin, A.; Peters, M.; Pi, B.; Piekarz, H.; Pischalnikov, Yu.; Pizzuto, D.; Pluquet, A.; Podstavkov, V.; Pope, B. G.; Prosper, H. B.; Protopopescu, S.; Que, Y.-K.; Quintas, P. Z.; Rahal-Callot, G.; Raja, R.; Rajagopalan, S.; Rao, M. V. S.; Rasmussen, L.; Read, A. L.; Regan, T.; Repond, S.; Riadovikov, V.; Rijssenbeek, M.; Roe, N. A.; Rubinov, P.; Rutherfoord, J.; Santoro, A.; Sawyer, L.; Schamberger, R. D.; Sculli, J.; Selove, W.; Shea, M.; Shkurenkov, A.; Shupe, M.; Singh, J. B.; Sirotenko, V.; Smart, W.; Smith, A.; Smith, D.; Smith, R. P.; Snow, G. R.; Snyder, S.; Sosebee, M.; Souza, M.; Spadafora, A. L.; Stampke, S.; Stephens, R.; Stevenson, M. L.; Stewart, D.; Stocker, F.; Stoyanova, D.; Stredde, H.; Streets, K.; Strovink, M.; Suhanov, A.; Taketani, A.; Tartaglia, M.; Taylor, J. D.; Teiger, J.; Theodosiou, G.; Thompson, J.; Tisserant, S.; Trippe, T. G.; Tuts, P. M.; Van Berg, R.; Vaz, M.; Vishwanath, P. R.; Volkov, A.; Vorobiev, A.; Wahl, H. D.; Wang, D.-C.; Wang, L.-Z.; Weerts, H.; Wenzel, W. A.; White, A.; White, J. T.; Wightman, J.; Willis, S.; Wimpenny, S. J.; Wolf, Z.; Womersley, J.; Wood, D. R.; Xia, Y.; Xiao, D.; Xie, P.; Xu, H.; Yamada, R.; Yamin, P.; Yanagisawa, C.; Yang, J.; Yang, M.-J.; Yoshikawa, C.; Youssef, S.; Yu, J.; Zeller, R.; Zhang, S.; Zhou, Y. H.; Zhu, Q.; Zhu, Y.-S.; Zieminska, D.; Zieminski, A.; Zinchenko, A.; Zylberstejn, A.; DØ Collaboration

    1994-01-01

    The DØ detector is a large general purpose detector for the study of short-distance phenomena in high energy antiproton-proton collisions, now in operation at the Fermilab Tevatron collider. The detector focusses upon the detection of electrons, muons, jets and missing transverse momentum. We describe the design and performance of the major elements of the detector, including the tracking chambers, transition radiation detector, liquid argon calorimetry and muon detection. The associated electronics, triggering systems and data acquisition systems are presented. The global mechanical, high voltage, and experiment monitoring and control systems which support the detector are described. We also discuss the design and implementation of software and software support systems that are specific to DØ.

  2. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  3. Noble Gas Detectors

    CERN Document Server

    Aprile, Elena; Bolozdynya, Alexander I; Doke, Tadayoshi

    2006-01-01

    This book discusses the physical properties of noble fluids, operational principles of detectors based on these media, and the best technical solutions to the design of these detectors. Essential attention is given to detector technology: purification methods and monitoring of purity, information readout methods, electronics, detection of hard ultra-violet light emission, selection of materials, cryogenics etc.The book is mostly addressed to physicists and graduate students involved in the preparation of fundamental next generation experiments, nuclear engineers developing instrumentation

  4. ATLAS inner detector performance

    CERN Document Server

    Gadomski, S

    2001-01-01

    The ATLAS Inner Detector consists of three subsystems using different tracking detector technologies: silicon pixels, silicon strips and straw tubes. The combination gives ATLAS a robust, hermetic and efficient tracking system, able to reconstruct tracks at the highest foreseen LHC luminosities. The inner detector provides vertex and momentum measurements, electron identification and some $K/\\pi$ separation. Since last year the beam pipe of ATLAS was changed, causing a redesign of the first tracking layer and a deterioration of the impact parameter resolutions.

  5. Contribution of a germanium detector in mobile gamma-ray spectrometry. Spectral analysis and performance

    CERN Document Server

    Gutierrez, S; Bourgeois, C

    2002-01-01

    The sensitivity of the germanium semi-conductor detector is 30 times lower than that of the sodium iodide (NaI) detectors frequently used in airborne spectrometry. Its energy resolution however, is 20 times better, giving more accurate identification of radionuclides, especially when complex spectra are involved. The use of the germanium detector in mobile gamma-ray spectrometry provides a large amount of qualitative and quantitative information. In post-accident situations a germanium detector will be sufficient, and should therefore be used in preference to a NaI detector. An algorithm for detecting the total absorption peaks by studying the variations in the spectral profile of germanium gamma-ray spectra has been developed at the CEA. The use of digital filters that take into account the characteristics of the absorption peaks reduces the statistical fluctuations, making possible detection based on the analysis of the first and second derivatives. The absorption peak is then estimated by subtracting the b...

  6. LHCb Detector Performance

    CERN Document Server

    AUTHOR|(CDS)2075808; Adeva, Bernardo; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Pessina, Gianluigi; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2015-01-01

    The LHCb detector is a forward spectrometer at the Large Hadron Collider (LHC) at CERN. The experiment is designed for precision measurements of CP violation and rare decays of beauty and charm hadrons. In this paper the performance of the various LHCb sub-detectors and the trigger system are described, using data taken from 2010 to 2012. It is shown that the design criteria of the experiment have been met. The excellent performance of the detector has allowed the LHCb collaboration to publish a wide range of physics results, demonstrating LHCb's unique role, both as a heavy flavour experiment and as a general purpose detector in the forward region.

  7. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS/LHC. The ALFA system is composed by two stations installed in the LHC tunnel 240 m away from each side of the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronic for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  8. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS (A Toroidal LHC Apparatus). The ALFA system is composed by four stations installed in the LHC tunnel 240 m away from the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronics for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  9. Photocapacitive MIS infrared detectors

    Science.gov (United States)

    Sher, A.; Lu, S. S.-M.; Moriarty, J. A.; Crouch, R. K.; Miller, W. E.

    1978-01-01

    A new class of room-temperature infrared detectors has been developed through use of metal-insulator-semiconductor (MIS) or metal-insulator-semiconductor-insulator-metal (MISIM) slabs. The detectors, which have been fabricated from Si, Ge and GaAs, rely for operation on the electrical capacitance variations induced by modulated incident radiation. The peak detectivity for a 1000-A Si MISIM detector is comparable to that of a conventional Si detector functioning in the photovoltaic mode. Optimization of the photocapacitive-mode detection sensitivity is discussed.

  10. Heterojunction and superlattice detectors for infrared to ultraviolet

    Science.gov (United States)

    Perera, A. G. U.

    2016-07-01

    The interest in Infrared and Ultraviolet detectors has increased immensely due to the emergence of important applications over a wide range of activities. Detectors based on free carrier absorption known as Hetero-junction Interfacial Workfunction Internal Photoemission (HEIWIP) detectors and variations of these heterojunction structures to be used as intervalence band detectors for a wide wavelength region are presented. Although this internal photoemission concept is valid for all semiconductor materials systems, using a well-studied III-V system of GaAs/AlxGa1-x As to cover a wide wavelength range from UV to far-infrared (THz) is an important development in detector technology. Using the intervalence band (heavy hole, light hole and split off) transitions for high operating temperature detection of mid Infrared radiation is also discussed. A promising new way to extend the detection wavelength threshold beyond the standard threshold connected with the energy gap in a GaAs/AlxGa1-x As system is also presented. Superlattice detector technology, which is another promising detector architecture, can be optimized using both Type I and Type II heterostructures. Here the focus will be on Type II Strained Layer (T2SL) Superlattice detectors. T2SL Superlattices based on InAs/(In,GA)Sb have made significant improvements demonstrating focal plane arrays operating around 80 K and with multiple band detection capability. A novel spectroscopic method to evaluate the band offsets of both heterojunction and superlattice detectors is also discussed.

  11. 离子交换电雾检测测定CO2吸收液中一乙醇胺、二乙醇胺、N-甲基二乙醇胺%Determination of monoethanolamine, diethanolamine and diethanolmethylamine in the absorption liquid of CO2 by ion chromatography with charged aerosol detector

    Institute of Scientific and Technical Information of China (English)

    叶明立; 陈郁

    2011-01-01

    A method was developed for the determination of monoethanolamine, diethanolamine and Diethanolmeth-ylamine in the absorption liquid of CO2 by cation-exchange ion chromatography with charged aerosol detector (CAD). Chromatographic separation was performed on a Dionex IonPac CS17(250×4 mm) , fomic acid and acetoni-trile were used as eluent, respectively. The effects of the types of column, eluent, eluent concentration of organic alcohol amines were investigated. The linear ranges of the method for three alcohol amines were 1. 0~100μg · mL-1 , the correlation coefficients were 0. 9996, 0. 9993 and 0. 9992, and the detection limits ( S/N = 3) were 0. 21,0. 04, 0. 32 μg · mL-1 respectively. The method was successfully applied to determine organic alcohol amines in real sample. The recoveries of three organic alcohol amines after spiking were from 87% to 98%.%建立了阳离子交换—电雾检测器测定CO2吸收液中一乙醇胺、二乙醇胺、N-甲基二乙醇胺的分析方法.实验采用IonPac CS17阳离子交换柱,选用甲酸与乙腈溶液为淋洗液,并考察了色谱柱种类、淋洗液种类与浓度对分离测定有机醇胺的影响.所测3种有机醇胺的检出限分别为0.21、0.04、0.32 μg·mL-1,线性范围在1.0~100 μg·mL-1,相关系数分别为0.999 6、0.999 3和0.999 2,加标回收率为87%~98%.用所建立的方法测定了CO2吸收液中有机胺质量浓度,结果令人满意.

  12. A measurement method of a detector response function for monochromatic electrons based on the Compton scattering

    Science.gov (United States)

    Bakhlanov, S. V.; Bazlov, N. V.; Derbin, A. V.; Drachnev, I. S.; Kayunov, A. S.; Muratova, V. N.; Semenov, D. A.; Unzhakov, E. V.

    2016-06-01

    In this paper we present a method of scintillation detector energy calibration using the gamma-rays. The technique is based on the Compton scattering of gamma-rays in a scintillation detector and subsequent photoelectric absorption of the scattered photon in the Ge-detector. The novelty of this method is that the source of gamma rays, the germanium and scintillation detectors are immediately arranged adjacent to each other. The method presents an effective solution for the detectors consisting of a low atomic number materials, when the ratio between Compton effect and photoelectric absorption is large and the mean path of gamma-rays is comparable to the size of the detector. The technique can be used for the precision measurements of the scintillator light yield dependence on the electron energy.

  13. A measurement method of a detector response function for monochromatic electrons based on the Compton scattering

    CERN Document Server

    Bakhlanov, S V; Derbin, A V; Drachnev, I S; Kayunov, A S; Muratova, V N; Semenov, D A; Unzhakov, E V

    2016-01-01

    In this paper we present a method of scintillation detector energy calibration using the gamma-rays. The technique is based on the Compton scattering of gamma-rays in a scintillation detector and subsequent photoelectric absorption of the scattered photon in the Ge-detector. The novelty of this method is that the source of gamma rays, the germanium and scintillation detectors are immediately arranged adjacent to each other. The method presents an effective solution for the detectors consisting of a low atomic number materials, when the ratio between Compton effect and photoelectric absorption is large and the mean path of gamma-rays is comparable to the size of the detector. The technique can be used for the precision measurements of the scintillator light yield dependence on the electron energy.

  14. A measurement method of a detector response function for monochromatic electrons based on the Compton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Bakhlanov, S.V. [St.Petersburg Nuclear Physics Institute, National Research Center “Kurchatov Institute”, Gatchina 188300 (Russian Federation); Bazlov, N.V. [Saint-Petersburg State University, Universitetskaja nab. 7/9, Saint-Petersburg 199034 (Russian Federation); Derbin, A.V., E-mail: derbin@pnpi.spb.ru [St.Petersburg Nuclear Physics Institute, National Research Center “Kurchatov Institute”, Gatchina 188300 (Russian Federation); Drachnev, I.S. [St.Petersburg Nuclear Physics Institute, National Research Center “Kurchatov Institute”, Gatchina 188300 (Russian Federation); GranSasso Science Institute, INFN, L' Aquila (AQ) I-67100 (Italy); Kayunov, A.S.; Muratova, V.N.; Semenov, D.A.; Unzhakov, E.V. [St.Petersburg Nuclear Physics Institute, National Research Center “Kurchatov Institute”, Gatchina 188300 (Russian Federation)

    2016-06-11

    In this paper we present a method of scintillation detector energy calibration using the gamma-rays. The technique is based on the Compton scattering of gamma-rays in a scintillation detector and subsequent photoelectric absorption of the scattered photon in the Ge-detector. The novelty of this method is that the source of gamma rays, the germanium and scintillation detectors are immediately arranged adjacent to each other. The method presents an effective solution for the detectors consisting of a low atomic number materials, when the ratio between Compton effect and photoelectric absorption is large and the mean path of gamma-rays is comparable to the size of the detector. The technique can be used for the precision measurements of the scintillator light yield dependence on the electron energy.

  15. ALICE Photon Multiplicity Detector

    CERN Multimedia

    Nayak, T

    2013-01-01

    Photon Multiplicity Detector (PMD) measures the multiplicity and spatial distribution of photons in the forward region of ALICE on a event-by-event basis. PMD is a pre-shower detector having fine granularity and full azimuthal coverage in the pseudo-rapidity region 2.3 < η < 3.9.

  16. Detector Systems at CLIC

    CERN Document Server

    Simon, Frank

    2011-01-01

    The Compact Linear Collider CLIC is designed to deliver e+e- collisions at a center of mass energy of up to 3 TeV. The detector systems at this collider have to provide highly efficient tracking and excellent jet energy resolution and hermeticity for multi-TeV final states with multiple jets and leptons. In addition, the detector systems have to be capable of distinguishing physics events from large beam-induced background at a crossing frequency of 2 GHz. Like for the detector concepts at the ILC, CLIC detectors are based on event reconstruction using particle flow algorithms. The two detector concepts for the ILC, ILD and SID, were adapted for CLIC using calorimeters with dense absorbers limiting leakage through increased compactness, as well as modified forward and vertex detector geometries and precise time stamping to cope with increased background levels. The overall detector concepts for CLIC are presented, with particular emphasis on the main detector and engineering challenges, such as: the ultra-thi...

  17. ALICE Silicon Strip Detector

    CERN Multimedia

    Nooren, G

    2013-01-01

    The Silicon Strip Detector (SSD) constitutes the two outermost layers of the Inner Tracking System (ITS) of the ALICE Experiment. The SSD plays a crucial role in the tracking of the particles produced in the collisions connecting the tracks from the external detectors (Time Projection Chamber) to the ITS. The SSD also contributes to the particle identification through the measurement of their energy loss.

  18. CMS Detector Posters

    CERN Multimedia

    2016-01-01

    CMS Detector posters (produced in 2000): CMS installation CMS collaboration From the Big Bang to Stars LHC Magnetic Field Magnet System Trackering System Tracker Electronics Calorimetry Eletromagnetic Calorimeter Hadronic Calorimeter Muon System Muon Detectors Trigger and data aquisition (DAQ) ECAL posters (produced in 2010, FR & EN): CMS ECAL CMS ECAL-Supermodule cooling and mechatronics CMS ECAL-Supermodule assembly

  19. Pixel detector readout chip

    CERN Multimedia

    1991-01-01

    Close-up of a pixel detector readout chip. The photograph shows an aera of 1 mm x 2 mm containing 12 separate readout channels. The entire chip contains 1000 readout channels (around 80 000 transistors) covering a sensitive area of 8 mm x 5 mm. The chip has been mounted on a silicon detector to detect high energy particles.

  20. The LDC detector concept

    Indian Academy of Sciences (India)

    Ties Behnke; LDC Concept Group

    2007-11-01

    In preparation of the experimental program at the international linear collider (ILC), the large detector concept (LDC) is being developed. The main points of the LDC are a large volume gaseous tracking system, combined with high precision vertex detector and an extremely granular calorimeter. The main design force behind the LDC is the particle flow concept.

  1. Introduction to detectors

    CERN Document Server

    Walenta, Albert H

    1995-01-01

    Concepts for momentum measurements,particle identification and energy measurements (calorimeters) as well for imaging applications in medecine, biology and industry (non destructive testing) will be put into relation to the specific detection princip In particular the resolution for position, time, energy and intensity measurement and the efficiency will be discussed. Signal extraction,electronic signal processing and principles of information capture will close the logic circle to the input : the radiation properties.The lecture will provide some sources for data tables and small demonstration computer programs f The basic detector physics as interaction of radiation with matter, information transport via free charges,photons and phonons and the signal formation will be presented in some depth with emphasis on the influence on specific parameters for detector The lecture will cover the most popular detector principles, gas detectors (ion chambers,MPWC's and MSGC's), semiconductor detectors scintillators and ...

  2. Nanomechanical resonance detector

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, Jeffrey C; Zettl, Alexander K

    2013-10-29

    An embodiment of a nanomechanical frequency detector includes a support structure and a plurality of elongated nanostructures coupled to the support structure. Each of the elongated nanostructures has a particular resonant frequency. The plurality of elongated nanostructures has a range of resonant frequencies. An embodiment of a method of identifying an object includes introducing the object to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the object. An embodiment of a method of identifying a molecular species of the present invention includes introducing the molecular species to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the molecular species.

  3. The PERDaix detector

    Energy Technology Data Exchange (ETDEWEB)

    Bachlechner, Andreas; Beischer, Bastian; Greim, Roman [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany); Kirn, Thomas, E-mail: kirn@physik.rwth-aachen.de [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany); Mai, Carsten; Yearwood, Gregorio Roper; Schael, Stefan; Schug, David; Tholen, Heiner; Wienkenhoever, Jens [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany)

    2012-12-11

    The PERDaix (Proton Electron Radiation Detector Aix-la-Chapelle) detector is designed to measure charged particles in cosmic rays. It can distinguish particle species up to 5 GV rigidity. PERDaix was flown on the BEXUS-11 balloon on 23rd November 2010. The detector has the dimensions of 246 Multiplication-Sign 400 Multiplication-Sign 859 mm{sup 3}, a geometrical acceptance of 32 cm{sup 2}sr, a low weight of 40 kg and a low power consumption of 60 W. The spectrometer consists of a time-of-flight system, a scintillating fiber tracking detector, a permanent magnet and a transition radiation detector. Silicon photomultipliers are used as photodetectors in the time-of-flight and the tracker system.

  4. The PERDaix detector

    Science.gov (United States)

    Bachlechner, Andreas; Beischer, Bastian; Greim, Roman; Kirn, Thomas; Mai, Carsten; Yearwood, Gregorio Roper; Schael, Stefan; Schug, David; Tholen, Heiner; Wienkenhöver, Jens

    2012-12-01

    The PERDaix (Proton Electron Radiation Detector Aix-la-Chapelle) detector is designed to measure charged particles in cosmic rays. It can distinguish particle species up to 5 GV rigidity. PERDaix was flown on the BEXUS-11 balloon on 23rd November 2010. The detector has the dimensions of 246×400×859 mm3, a geometrical acceptance of 32 cm2sr, a low weight of 40 kg and a low power consumption of 60 W. The spectrometer consists of a time-of-flight system, a scintillating fiber tracking detector, a permanent magnet and a transition radiation detector. Silicon photomultipliers are used as photodetectors in the time-of-flight and the tracker system.

  5. ATLAS ITk Pixel detector

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration

    2016-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

  6. Performance of an AGATA prototype detector estimated by Compton-imaging techniques

    Energy Technology Data Exchange (ETDEWEB)

    Recchia, F. [INFN Legnaro (Italy)], E-mail: francesco.recchia@pd.infn.it; Bazzacco, D.; Farnea, E.; Venturelli, R. [INFN Padova (Italy); Aydin, S. [INFN Padova (Italy); Aksaray University (Turkey); Suliman, G. [IFIN-HH, Bucharest (Romania); Ur, C.A. [INFN Padova (Italy)

    2009-06-01

    The imaging capabilities of an AGATA detector have been determined experimentally. Fundamental information on the detector performance can be obtained by a back-projection of the events consisting in a Compton scattering and a subsequent photoelectric absorption. The procedure presented will allow to obtain a feedback on the over-all position resolution of tracking detectors with a high energy resolution. Thanks to its simplicity the method will be used to guarantee the maximal operational performance of tracking arrays such as AGATA.

  7. Adsorption smoke detector made of thin-film metal-oxide semiconductor sensor

    CERN Document Server

    Adamian, A Z; Aroutiounian, V M

    2001-01-01

    Based on results of investigations of the thin-film smoke sensors made of Bi sub 2 O sub 3 , irresponsive to a change in relative humidity of the environment, an absorption smoke detector processing circuit, where investigated sensor is used as a sensitive element, is proposed. It is shown that such smoke detector is able to function reliably under conditions of high relative humidity of the environment (up to 100%) and it considerably exceeds the known smoke detectors by the sensitivity threshold.

  8. The HI absorption "Zoo"

    NARCIS (Netherlands)

    Geréb, K.; Maccagni, F. M.; Morganti, R.; Oosterloo, T. A.

    2015-01-01

    We present an analysis of the H I 21 cm absorption in a sample of 101 flux-selected radio AGN (S1.4 GHz> 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). We detect H I absorption in 32 objects (30% of the sample). In a previous paper, we performed a spectral stacking analysis o

  9. Bioacoustic Absorption Spectroscopy

    Science.gov (United States)

    2016-06-07

    frequencies (Ching and Weston, 1971). RESULTS Measured resonance frequencies of absorption lines, which were attributed to adult (~ 1.3 khz) and juvenile ...of adult and juvenile sardines. These results suggest that bioacoustic absorption spectroscopy measurements permit isolation of juvenile from adult...from broadband tomographic transmission loss measurements over large areas . 2. Depths of sardines and contours of phytoplankton concentrations vs. time

  10. Nutrition and magnesium absorption.

    NARCIS (Netherlands)

    Brink, E.J.

    1992-01-01

    The influence of various nutrients present in dairy products and soybean-based products on absorption of magnesium has been investigated. The studies demonstrate that soybean protein versus casein lowers apparent magnesium absorption in rats through its phytate component. However, true magnesium abs

  11. [Study on cadmium absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Jing, Rui-Jun; Dong, Wei-Hua; Li, Xin-Zheng; Liu, Hong

    2006-08-01

    A study was carried out on the characteristic of cadmium absorption in pumpkin by atomic absorption spectrophotometer. The results show that the cadmium absorption amount in pumpkin increased with the increase in cadmium concentration. Meanwhile the cadmium absorption amount in pumpkin increased with time. Eight hours after being cultured in the liquid, the cadmium absorption amount became saturated. The cadmium absorption rate reached the peak after 2 hours, then the absorption rate gradually reduced. The cadmium absorption amount in pumpkin is less in acid or alkali compared with neutral condition. And the absorption amount became minimum in pH 3, while maximum in pH 7.

  12. The HERMES recoil detector

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Aschenauer, E.C. [DESY, Zeuthen (Germany); Belostotski, S. [B.P. Konstantinov Petersburg Nuclear Physics Insitute, Gatchina (Russian Federation)] [and others; Collaboration: HERMES Recoil Detector Group

    2013-02-15

    For the final running period of HERA, a recoil detector was installed at the HERMES experiment to improve measurements of hard exclusive processes in charged-lepton nucleon scattering. Here, deeply virtual Compton scattering is of particular interest as this process provides constraints on generalised parton distributions that give access to the total angular momenta of quarks within the nucleon. The HERMES recoil detector was designed to improve the selection of exclusive events by a direct measurement of the four-momentum of the recoiling particle. It consisted of three components: two layers of double-sided silicon strip sensors inside the HERA beam vacuum, a two-barrel scintillating fibre tracker, and a photon detector. All sub-detectors were located inside a solenoidal magnetic field with an integrated field strength of 1Tm. The recoil detector was installed in late 2005. After the commissioning of all components was finished in September 2006, it operated stably until the end of data taking at HERA end of June 2007. The present paper gives a brief overview of the physics processes of interest and the general detector design. The recoil detector components, their calibration, the momentum reconstruction of charged particles, and the event selection are described in detail. The paper closes with a summary of the performance of the detection system.

  13. Detectors for Tomorrow's Instruments

    Science.gov (United States)

    Moseley, Harvey

    2009-01-01

    Cryogenically cooled superconducting detectors have become essential tools for a wide range of measurement applications, ranging from quantum limited heterodyne detection in the millimeter range to direct searches for dark matter with superconducting phonon detectors operating at 20 mK. Superconducting detectors have several fundamental and practical advantages which have resulted in their rapid adoption by experimenters. Their excellent performance arises in part from reductions in noise resulting from their low operating temperatures, but unique superconducting properties provide a wide range of mechanisms for detection. For example, the steep dependence of resistance with temperature on the superconductor/normal transition provides a sensitive thermometer for calorimetric and bolometric applications. Parametric changes in the properties of superconducting resonators provides a mechanism for high sensitivity detection of submillimeter photons. From a practical point of view, the use of superconducting detectors has grown rapidly because many of these devices couple well to SQUID amplifiers, which are easily integrated with the detectors. These SQUID-based amplifiers and multiplexers have matured with the detectors; they are convenient to use, and have excellent noise performance. The first generation of fully integrated large scale superconducting detection systems are now being deployed. I will discuss the prospects for a new generation of instruments designed to take full advantage of the revolution in detector technology.

  14. The Belle II Detector

    Science.gov (United States)

    Piilonen, Leo; Belle Collaboration, II

    2017-01-01

    The Belle II detector is now under construction at the KEK laboratory in Japan. This project represents a substantial upgrade of the Belle detector (and the KEKB accelerator). The Belle II experiment will record 50 ab-1 of data, a factor of 50 more than that recorded by Belle. This large data set, combined with the low backgrounds and high trigger efficiencies characteristic of an e+e- experiment, should provide unprecedented sensitivity to new physics signatures in B and D meson decays, and in τ lepton decays. The detector comprises many forefront subsystems. The vertex detector consists of two inner layers of silicon DEPFET pixels and four outer layers of double-sided silicon strips. These layers surround a beryllium beam pipe having a radius of only 10 mm. Outside of the vertex detector is a large-radius, small-cell drift chamber, an ``imaging time-of-propagation'' detector based on Cerenkov radiation for particle identification, and scintillating fibers and resistive plate chambers used to identify muons. The detector will begin commissioning in 2017.

  15. ATLAS Detector Interface Group

    CERN Multimedia

    Mapelli, L

    Originally organised as a sub-system in the DAQ/EF-1 Prototype Project, the Detector Interface Group (DIG) was an information exchange channel between the Detector systems and the Data Acquisition to provide critical detector information for prototype design and detector integration. After the reorganisation of the Trigger/DAQ Project and of Technical Coordination, the necessity to provide an adequate context for integration of detectors with the Trigger and DAQ lead to organisation of the DIG as one of the activities of Technical Coordination. Such an organisation emphasises the ATLAS wide coordination of the Trigger and DAQ exploitation aspects, which go beyond the domain of the Trigger/DAQ project itself. As part of Technical Coordination, the DIG provides the natural environment for the common work of Trigger/DAQ and detector experts. A DIG forum for a wide discussion of all the detector and Trigger/DAQ integration issues. A more restricted DIG group for the practical organisation and implementation o...

  16. Preliminary Results on Compton Electrons in Silicon Drift Detector

    Science.gov (United States)

    Conka-Nurdan, T.; Nurdan, K.; Laihem, K.; Walenta, A. H.; Fiorini, C.; Freisleben, B.; Hornel, N.; Pavel, N. A.; Struder, L.

    2004-10-01

    Silicon drift detectors (SDD) with on-chip electronics have found many applications in different fields. A detector system has recently been designed and built to study the electrons from Compton scatter events in such a detector. The reconstruction of the Compton electrons is a crucial issue for Compton imaging. The equipment consists of a monolithic array of 19 channel SDDs and an Anger camera. Photons emitted from a finely collimated source undergo Compton scattering within the SDD where the recoil electron is absorbed. The scattered photon is subsequently observed by photoelectric absorption in the second detector. The coincidence events are used to get the energy, position, and direction of the Compton electrons. Because the on-chip transistors provide the first stage amplification, the SDDs provide outstanding noise performance and fast shaping, so that very good energy resolution can be obtained even at room temperature. The drift detectors require a relatively low number of readout channels for large detector areas. Custom-designed analog and digital electronics provide fast readout of the SDDs. The equipment is designed such that the measurements can be done in all detector orientations and kinematical conditions. The first results obtained with this detector system will be presented in this paper.

  17. Theoretical investigation of very high quantum efficiency, segmented, crystalline detectors for low-contrast visualization in megavoltage cone-beam CT

    Science.gov (United States)

    Wang, Yi; Antonuk, Larry E.; El-Mohri, Youcef; Sawant, Amit; Zhao, Qihua; Du, Hong; Li, Yixin

    2006-03-01

    Megavoltage cone-beam computed tomography (CBCT) using active matrix flat-panel imagers (AMFPIs) is a promising candidate for providing image guidance in radiation therapy. Unfortunately, the practical clinical implementation of this technique is limited by the relatively low detective quantum efficiency (DQE) of conventional megavoltage AMFPIs. This limitation is due to the modest thickness of the phosphor screen employed to convert incident x-rays to optical photons and the trade-off that exists between phosphor thickness and spatial resolution. Recently, our group has begun pursuing the development of thick crystalline segmented scintillating detectors as x-ray converters for AMFPIs so as to circumvent this limitation. In order to examine the potential of such detectors for providing soft-tissue visualization by means of CBCT at megavoltage energies, a Monte Carlo-based method was used to simulate the acquisition of projection images of a contrast phantom. These images were used to perform CT reconstructions by means of a Feldkamp-based algorithm. In this study, various detector configurations involving CsI and BGO scintillators at thicknesses of 10 mm and 40 mm were evaluated. In addition, since the simulations only considered energy deposition, and did not include optical phenomena, both segmented and non-segmented (continuous) detector configurations were evaluated. For the segmented CsI detectors, septal wall materials with densities lower, equivalent and higher than that of the scintillator were considered. Performance was quantified in terms of the contrast-to-noise ratio obtained for lowcontrast, soft-tissue-equivalent objects (i.e., liver, brain, and breast) embedded in the phantom. The results obtained from these early studies suggest that such segmented converters can provide visualization of soft-tissue contrast in tomographic images at clinically practical doses. It is anticipated that the realization of optimized segmented detector designs will lead

  18. Detectors - Electronics; Detecteurs - Electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)

    1998-04-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X {yields} e{sup -} converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the {sup 3}He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  19. Universal Zero Conductivity Condition for Optical Absorption

    CERN Document Server

    Guo, Yu; Jacob, Zubin

    2016-01-01

    Harnessing information and energy from light within a nanoscale mode volume is a fundamental challenge for nanophotonic applications ranging from solar photovoltaics to single photon detectors. Here, we show the existence of a universal condition in materials that sheds light on fundamental limits of electromagnetic to matter energy conversion (transduction). We show that the upper limit of absorption rate (transduction rate) in any nanoscale absorber converting light to matter degrees of freedom is revealed by the zero of optical conductivity at complex frequencies ($\\sigma(\\omega^\\prime + i\\omega^{\\prime\\prime})= 0$). We trace the origin of this universal zero conductivity condition to causality requirements on any passive linear response function and propose an experiment of absorption resonances using plasmonic nanoparticles to experimentally verify this universal zero conductivity condition. Our work is widely applicable to linear systems across the electromagnetic spectrum and allows for systematic opti...

  20. Detector resolution in positron annihilation Doppler broadening experiments

    Science.gov (United States)

    Heikinheimo, J.; Ala-Heikkilä, J.; Tuomisto, F.

    2017-09-01

    Positron annihilation Doppler broadening spectroscopy characterizes lattice point defects and is sensitive to very small vacancy densities. High-purity germanium detectors are generally used for recording the Doppler broadening spectrum because they provide good energy resolution and stability. However, the energy resolution of a germanium detector is somewhat dependent on the photon absorption geometry in the detector crystal. This change in the energy resolution changes also the Doppler broadening parameters. To observe the dependency of the resolution function and the Doppler broadening parameters, we performed experiments on Si samples in standard sandwich configuration with a Na-22 source. We changed the radiation geometry of the incident gamma photons via altering the distance of the sample-source package from the detector and by adding steel between the source and the detector. We observed the change of the absorption geometry in the germanium detector crystal by doing Monte Carlo simulations. The aim of this study is to help understand and decide what is the best way to compare the Doppler broadening parameters obtained with different measurement setups and even with the same setup when the geometry in the measurements has changed.

  1. Performance of GLD detector

    Indian Academy of Sciences (India)

    T Yoshioka

    2007-12-01

    Most of the important physics processes to be studied in the international linear collider (ILC) experiment have multi-jets in the final state. In order to achieve better jet energy resolution, the so-called particle flow algorithm (PFA) will be employed and there is a general consensus that PFA derives overall ILC detector design. Four detector concepts for the ILC experiment have been proposed so far in the world; the GLD detector that has a large inner calorimeter radius, which is considered to have an advantage for a PFA, is one of them. In this paper, general scheme and performance of the GLD-PFA will be presented.

  2. Microfluidic Scintillation Detectors

    CERN Multimedia

    Microfluidic scintillation detectors are devices of recent introduction for the detection of high energy particles, developed within the EP-DT group at CERN. Most of the interest for such technology comes from the use of liquid scintillators, which entails the possibility of changing the active material in the detector, leading to an increased radiation resistance. This feature, together with the high spatial resolution and low thickness deriving from the microfabrication techniques used to manufacture such devices, is desirable not only in instrumentation for high energy physics experiments but also in medical detectors such as beam monitors for hadron therapy.

  3. The Silicon Cube detector

    Energy Technology Data Exchange (ETDEWEB)

    Matea, I.; Adimi, N. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France); Blank, B. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France)], E-mail: blank@cenbg.in2p3.fr; Canchel, G.; Giovinazzo, J. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France); Borge, M.J.G.; Dominguez-Reyes, R.; Tengblad, O. [Insto. Estructura de la Materia, CSIC, Serrano 113bis, E-28006 Madrid (Spain); Thomas, J.-C. [GANIL, CEA/DSM - CNRS/IN2P3, BP 55027, F-14076 Caen Cedex 5 (France)

    2009-08-21

    A new experimental device, the Silicon Cube detector, consisting of six double-sided silicon strip detectors placed in a compact geometry was developed at CENBG. Having a very good angular coverage and high granularity, it allows simultaneous measurements of energy and angular distributions of charged particles emitted from unbound nuclear states. In addition, large-volume Germanium detectors can be placed close to the collection point of the radioactive species to be studied. The setup is ideally suited for isotope separation on-line (ISOL)-type experiments to study multi-particle emitters and was tested during an experiment at the low-energy beam line of SPIRAL at GANIL.

  4. ATLAS Inner Detector Alignment

    CERN Document Server

    Bocci, A

    2008-01-01

    The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider at CERN. In order to achieve its physics goals, the ATLAS tracking requires that the positions of the silicon detector elements have to be known to a precision better than 10 μm. Several track-based alignment algorithms have been developed for the Inner Detector. An extensive validation has been performed with simulated events and real data coming from the ATLAS. Results from such validation are reported in this paper.

  5. Directional radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  6. Quasar Absorption Studies

    Science.gov (United States)

    Mushotzky, Richard (Technical Monitor); Elvis, Martin

    2004-01-01

    The aim of the proposal is to investigate the absorption properties of a sample of inter-mediate redshift quasars. The main goals of the project are: Measure the redshift and the column density of the X-ray absorbers; test the correlation between absorption and redshift suggested by ROSAT and ASCA data; constrain the absorber ionization status and metallicity; constrain the absorber dust content and composition through the comparison between the amount of X-ray absorption and optical dust extinction. Unanticipated low energy cut-offs where discovered in ROSAT spectra of quasars and confirmed by ASCA, BeppoSAX and Chandra. In most cases it was not possible to constrain adequately the redshift of the absorber from the X-ray data alone. Two possibilities remain open: a) absorption at the quasar redshift; and b) intervening absorption. The evidences in favour of intrinsic absorption are all indirect. Sensitive XMM observations can discriminate between these different scenarios. If the absorption is at the quasar redshift we can study whether the quasar environment evolves with the Cosmic time.

  7. Infrared microcalorimetric spectroscopy using uncooled thermal detectors

    Energy Technology Data Exchange (ETDEWEB)

    Datskos, P.G. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy]|[Oak Ridge National Lab., TN (United States); Rajic, S.; Datskou, I.; Egert, C.M. [Oak Ridge National Lab., TN (United States)

    1997-10-01

    The authors have investigated a novel infrared microcalorimetric spectroscopy technique that can be used to detect the presence of trace amounts of target molecules. The chemical detection is accomplished by obtaining the infrared photothermal spectra of molecules absorbed on the surface of an uncooled thermal detector. Traditional gravimetric based chemical detectors (surface acoustic waves, quartz crystal microbalances) require highly selective coatings to achieve chemical specificity. In contrast, infrared microcalorimetric based detection requires only moderately specific coatings since the specificity is a consequence of the photothermal spectrum. They have obtained infrared photothermal spectra for trace concentrations of chemical analytes including diisopropyl methylphosphonate (DIMP), 2-mercaptoethanol and trinitrotoluene (TNT) over the wavelength region2.5 to 14.5 {micro}m. They found that in the wavelength region 2.5 to 14.5 {micro}m DIMP exhibits two strong photothermal peaks. The photothermal spectra of 2-mercaptoethanol and TNT exhibit a number of peaks in the wavelength region 2.5 to 14.5 {micro}m and the photothermal peaks for 2-mercaptoethanol are in excellent agreement with infrared absorption peaks present in its IR spectrum. The photothermal response of chemical detectors based on microcalorimetric spectroscopy has been found to vary reproducibly and sensitively as a consequence of adsorption of small number of molecules on a detector surface followed by photon irradiation and can be used for improved chemical characterization.

  8. 6Li foil thermal neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Ianakiev, Kiril D [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Favalli, Andrea [Los Alamos National Laboratory; Chung, Kiwhan [Los Alamos National Laboratory; Macarthur, Duncan W [Los Alamos National Laboratory

    2010-01-01

    In this paper we report on the design of a multilayer thermal neutron detector based on {sup 6}Li reactive foil and thin film plastic scintillators. The {sup 6}Li foils have about twice the intrinsic efficiency of {sup 10}B films and about four times higher light output due to a unique combination of high energy of reaction particles, low self absorption, and low ionization density of tritons. The design configuration provides for double sided readout of the lithium foil resulting in a doubling of the efficiency relative to a classical reactive film detector and generating a pulse height distribution with a valley between neutron and gamma signals similar to {sup 3}He tubes. The tens of microns thickness of plastic scintillator limits the energy deposited by gamma rays, which provides the necessary neutron/gamma discrimination. We used MCNPX to model a multilayer Li foil detector design and compared it with the standard HLNCC-II (18 {sup 3}He tubes operated at 4 atm). The preliminary results of the {sup 6}Li configuration show higher efficiency and one third of the die-away time. These properties, combined with the very short dead time of the plastic scintillator, offer the potential of a very high performance detector.

  9. Novel Photo-Detectors and Photo-Detector Systems

    OpenAIRE

    Danilov, M.

    2008-01-01

    Recent developments in photo-detectors and photo-detector systems are reviewed. The main emphasis is made on Silicon Photo-Multipliers (SiPM) - novel and very attractive photo-detectors. Their main features are described. Properties of detectors manufactured by different producers are compared. Different applications are discussed including calorimeters, muon detection, tracking, Cherenkov light detection, and time of flight measurements.

  10. Infrared Detectors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The end goal of this project is to develop proof-of-concept infrared detectors which can be integrated in future infrared instruments engaged in remote...

  11. ALICE Forward Multiplicity Detector

    CERN Multimedia

    Christensen, C

    2013-01-01

    The Forward Multiplicity Detector (FMD) extends the coverage for multiplicity of charge particles into the forward regions - giving ALICE the widest coverage of the 4 LHC experiments for these measurements.

  12. OPAL detector electromagnetic calorimeter

    CERN Multimedia

    1988-01-01

    Half of the electromagnetic calorimeter of the OPAL detector is seen in this photo. This calorimeter consists of 4720 blocks of lead glass. It was used to detect and measure the energy of photons, electrons and positrons by absorbing them.

  13. The LUX Prototype Detector

    CERN Document Server

    Akerib, D S; Bedikian, S; Bernstein, A; Bolozdynya, A; Bradley, A; Cahn, S; Carr, D; Chapman, J J; Clark, K; Classen, T; Curioni, A; Dahl, C E; Dazeley, S; deViveiros, L; Dragowsky, M; Druszkiewicz, E; Fiorucci, S; Gaitskell, R J; Hall, C; Faham, C; Holbrook, B; Kastens, L; Kazkaz, K; Kwong, J; Lander, R; Leonard, D; Malling, D; Mannino, R; McKinsey, D N; Mei, D; Mock, J; Morii, M; Nikkel, J; Phelps, P; Shutt, T; Skulski, W; Sorensen, P; Spaans, J; Steigler, T; Svoboda, R; Sweany, M; Thomson, J; Tripathi, M; Walsh, N; Webb, R; White, J; Wolfs, F L H; Woods, M; Zhang, C

    2012-01-01

    The LUX (Large Underground Xenon) detector is a two-phase xenon Time Projection Chamber (TPC) designed to search for WIMP-nucleon dark matter interactions. As with all noble element detectors, continuous purification of the detector medium is essential to produce a large ($>$1ms) electron lifetime; this is necessary for efficient measurement of the electron signal which in turn is essential for achieving robust discrimination of signal from background events. In this paper we describe the development of a novel purification system deployed in a prototype detector. The results from the operation of this prototype indicated heat exchange with an efficiency above 94% up to a flow rate of 42 slpm, allowing for an electron drift length greater than 1 meter to be achieved in approximately two days and sustained for the duration of the testing period.

  14. The CLIC Detector Concept

    CERN Document Server

    Pitters, Florian Michael

    2016-01-01

    CLIC is a concept for a future linear collider that would provide e+e- collisions at up to 3 TeV. The physics aims require a detector system with excellent jet energy and track momentum resolution, highly efficient flavour-tagging and lepton identification capabilities, full geometrical coverage extending to low polar angles and timing information in the order of nanoseconds to reject beam-induced background. To deal with those requirements, an extensive R&D programme is in place to overcome current technological limits. The CLIC detector concept includes a low-mass all-silicon vertex and tracking detector system and fine-grained calorimeters designed for particle flow analysis techniques, surrounded by a 4 T solenoid magnet. An overview of the requirements and design optimisations for the CLIC detector concept is presented.

  15. Hybrid photon detectors

    CERN Document Server

    D'Ambrosio, C

    2003-01-01

    Hybrid photon detectors detect light via vacuum photocathodes and accelerate the emitted photoelectrons by an electric field towards inversely polarized silicon anodes, where they are absorbed, thus producing electron-hole pairs. These, in turn, are collected and generate electronic signals on their ohmic contacts. This review first describes the characteristic properties of the main components of hybrid photon detectors: light entrance windows, photocathodes, and silicon anodes. Then, essential relations describing the trajectories of photoelectrons in electric and magnetic fields and their backscattering from the silicon anodes are derived. Depending on their anode configurations, three families of hybrid photon detectors are presented: hybrid photomultiplier tubes with single anodes for photon counting with high sensitivity and for gamma spectroscopy; multi-anode photon detector tubes with anodes subdivided into square or hexagonal pads for position-sensitive photon detection; imaging silicon pixel array t...

  16. GRAVITY detector systems

    Science.gov (United States)

    Mehrgan, Leander H.; Finger, Gert; Eisenhauer, Frank; Panduro, Johana

    2016-08-01

    GRAVITY is a second generation instrument for the VLT Interferometer, designed for high-precision narrow-angle astrometry and phase-referenced interferometric imaging in the K-band. It will combine the AO corrected beams of the four VLT telescopes. In total, the GRAVITY instrument uses five eAPD detectors four for the infrared wavefront sensors of each telescope and one for the fringe tracker. In addition two Hawaii2RG arrays are installed, one for the acquisition camera and one for the spectrometer. The SAPHIRA eAPD array is a newly developed near-infrared detector with sub-electron noise performance at frame rates > 1Kfps. For all seven detectors the ESO common controller, NGC, is used. This paper presents an overview and comparison of GRAVITY detector systems and their final performances at the telescope

  17. Pocked surface neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas (Whitmore Lake, MI); Klann, Raymond (Bolingbrook, IL)

    2003-04-08

    The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

  18. Europe plans megaton detector

    CERN Multimedia

    Cartlidge, Edwin

    2004-01-01

    A group of French and Italian particle physicists hopes to carry on the long tradition of building large underground detectors by constructing a device deep under the Alps containing a million tonnes of extremely pure water.

  19. The pixelated detector

    CERN Multimedia

    Sutton, C

    1990-01-01

    "Collecting data as patterns of light or subatomic particles is vitally important in all the sciences. The new generation of solid-state detectors called pixel devices could transform experimental research at all levels" (4 pages).

  20. Improved CO [lidar detector

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, P.L.; Busch, G.E.; Thompson, D.C.; Remelius, D.K.; Wells, F.D.

    1999-07-18

    A high sensitivity, CO{sub 2} lidar detector, based on recent advances in ultra-low noise, readout integrated circuits (ROIC), is being developed. This detector will combine a high speed, low noise focal plane array (FPA) with a dispersive grating spectrometer. The spectrometer will filter the large background flux, thereby reducing the limiting background photon shot noise. In order to achieve the desired low noise levels, the HgCdTe FPA will be cooled to {approximately}50K. High speed, short pulse operation of the lidar system should enable the detector to operate with the order of a few noise electrons in the combined detector/ ROIC output. Current receiver design concepts will be presented, along with their expected noise performance.

  1. Detector Control System for the ATLAS Forward Proton detector

    CERN Document Server

    Czekierda, Sabina; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) is a forward detector using a Roman Pot technique, recently installed in the LHC tunnel. It is aiming at registering protons that were diffractively or electromagnetically scattered in soft and hard processes. Infrastructure of the detector consists of hardware placed both in the tunnel and in the control room USA15 (about 330 meters from the Roman Pots). AFP detector, like the other detectors of the ATLAS experiment, uses the Detector Control System (DCS) to supervise the detector and to ensure its safe and coherent operation, since the incorrect detector performance may influence the physics results. The DCS continuously monitors the detector parameters, subset of which is stored in data bases. Crucial parameters are guarded by alarm system. A detector representation as a hierarchical tree-like structure of well-defined subsystems built with the use of the Finite State Machine (FSM) toolkit allows for overall detector operation and visualization. Every node in the hierarchy is...

  2. The AMANDA Neutrino Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wischnewski, R.; Andres, E.; Askebjer, P.; Barwick, S.; Bay, R.; Bergstroem, L.; Biron, A.; Booth, J.; Botner, O.; Bouchta, A.; Carius, S.; Carlson, M.; Chinowsky, W.; Chirkin, D.; Cowen, D.; Costa, C.; Dalberg, E.; Deyoung, T.; Edsjo, J.; Ekstroem, P.; Goobar, A.; Gray, L.; Hallgren, A.; Halzen, F.; Hardtke, R.; He, Y.; Hill, G.; Hulth, P.; Hundertmark, S.; Jacobsen, J.; Kandhadai, V.; Karle, A.; Kim, J.; Leich, H.; Leuthold, M.; Lindahl, P.; Liss, T.; Liubarsky, I.; Loaiza, P.; LOwder, D.; Marciniewski, P.; Miller, T.; Miocinovic, P.; Mock, P.; Morse, R.; Newcomer, M.; Niessen, P.; Nygren, D.; Perez de los Heros, C.; Porrata, R.; Price, P.; Przybylski, G.; Rhode, W.; Richter, S.; Rodriguez, J.; Romenesko, P.; Ross, D.; Rubinstein, H.; Schmidt, T.; Schneider, E.; Schwarz, R.; Schwendicke, U.; Smoot, G.; Solarz, M.; Sorin, V.; Spiering, C.; Steffen, P.; Stokstad, R.; Streicher, O.; Thollander, L.; Thon, T.; Tilav, S.; Walck, C.; Wiebusch, C.; Woschnagg, K.; Wu, W.; Yodh, G.; Young, S

    1999-03-01

    The first stage of the AMANDA High Energy Neutrino Detector at the South Pole, the 302 PMT array AMANDA-B with an expected effective area for TeV neutrinos of {approx} 10{sup 4} m{sup 2}, has been taking data since 1997. Progress with calibration, investigation of ice properties, as well as muon and neutrino data analysis are described. The next stage 20-string detector AMANDA-II with {approx}800 PMTs will be completed in spring 2000.

  3. Fiber optic detector

    Energy Technology Data Exchange (ETDEWEB)

    Partin, J.K.; Ward, T.E.; Grey, A.E.

    1990-12-31

    This invention is comprised of a portable fiber optic detector that senses the presence of specific target chemicals by exchanging the target chemical for a fluorescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

  4. Phi factory detector requirements

    Energy Technology Data Exchange (ETDEWEB)

    Arisaka, K.; Atac, M.; Berg, R.; Buchanan, C.; Calvette, M.; Khazin, B.; Kinoshita, K.; Muller, T.; Ohshima, T.; Olsen, S.; Park, J.; Santoni, C.; Shirai, J.; Solodov, E.; Thompson, J.; Triggiani, G.; Ueno, K.; Yamamoto, H.; Detector and Simulation Working Group

    1991-08-01

    We identify the experimental problems and the conditions required for successful phi-factory operation, and show the range of detector parameters which, in conjunction with different machine designs, may meet these conditions. We started by considering, comparing and criticizing the Italian and Novosibirsk designs. With this discussion as a background, we defined the apparent experimental problems and detector constraints. In this article we summarize our understanding. (orig./HSI).

  5. Soliton absorption spectroscopy

    CERN Document Server

    Kalashnikov, V L

    2010-01-01

    We analyze optical soliton propagation in the presence of weak absorption lines with much narrower linewidths as compared to the soliton spectrum width using the novel perturbation analysis technique based on an integral representation in the spectral domain. The stable soliton acquires spectral modulation that follows the associated index of refraction of the absorber. The model can be applied to ordinary soliton propagation and to an absorber inside a passively modelocked laser. In the latter case, a comparison with water vapor absorption in a femtosecond Cr:ZnSe laser yields a very good agreement with experiment. Compared to the conventional absorption measurement in a cell of the same length, the signal is increased by an order of magnitude. The obtained analytical expressions allow further improving of the sensitivity and spectroscopic accuracy making the soliton absorption spectroscopy a promising novel measurement technique.

  6. Absorption heat pump system

    Science.gov (United States)

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  7. Zeeman atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hadeishi, T.; McLaughlin, R.

    1978-08-01

    The design and development of a Zeeman atomic absorption spectrometer for trace element analysis are described. An instruction manual is included which details the operation, adjustment, and maintenance. Specifications and circuit diagrams are given. (WHK)

  8. Modelling semiconductor pixel detectors

    CERN Document Server

    Mathieson, K

    2001-01-01

    expected after 200 ps in most cases. The effect of reducing the charge carrier lifetime and examining the charge collection efficiency has been utilised to explore how these detectors would respond in a harsh radiation environment. It is predicted that over critical carrier lifetimes (10 ps to 0.1 ns) an improvement of 40 % over conventional detectors can be expected. This also has positive implications for fabricating detectors, in this geometry, from materials which might otherwise be considered substandard. An analysis of charge transport in CdZnTe pixel detectors has been performed. The analysis starts with simulation studies into the formation of contacts and their influence on the internal electric field of planar detectors. The models include a number of well known defect states and these are balanced to give an agreement with a typical experimental I-V curve. The charge transport study extends to the development of a method for studying the effect of charge sharing in highly pixellated detectors. The ...

  9. Gamma ray detector modules

    Science.gov (United States)

    Capote, M. Albert (Inventor); Lenos, Howard A. (Inventor)

    2009-01-01

    A radiation detector assembly has a semiconductor detector array substrate of CdZnTe or CdTe, having a plurality of detector cell pads on a first surface thereof, the pads having a contact metallization and a solder barrier metallization. An interposer card has planar dimensions no larger than planar dimensions of the semiconductor detector array substrate, a plurality of interconnect pads on a first surface thereof, at least one readout semiconductor chip and at least one connector on a second surface thereof, each having planar dimensions no larger than the planar dimensions of the interposer card. Solder columns extend from contacts on the interposer first surface to the plurality of pads on the semiconductor detector array substrate first surface, the solder columns having at least one solder having a melting point or liquidus less than 120 degrees C. An encapsulant is disposed between the interposer circuit card first surface and the semiconductor detector array substrate first surface, encapsulating the solder columns, the encapsulant curing at a temperature no greater than 120 degrees C.

  10. ATLAS Inner Detector (Pixel Detector and Silicon Tracker)

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    To raise awareness of the basic functions of the Pixel Detector and Silicon Tracker in the ATLAS detector on the LHC at CERN. This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the detector, seeing critical pieces of the detector and hearing short explanations of how each works.

  11. Revisiting Absorptive Capacity

    DEFF Research Database (Denmark)

    de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher

    Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...... learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning...

  12. Revisiting Absorptive Capacity

    DEFF Research Database (Denmark)

    de Araújo, Ana Luiza Lara; Ulhøi, John Parm; Lettl, Christopher

    Absorptive capacity has mostly been perceived as a 'passive' outcome of R&D investments. Recently, however, a growing interest into its 'proactive' potentials has emerged. This paper taps into this development and proposes a dynamic model for conceptualizing the determinants of the complementary...... learning processes of absorptive capacity, which comprise combinative and adaptive capabilities. Drawing on survey data (n=169), the study concludes that combinative capabilities primarily enhance transformative and exploratory learning processes, while adaptive capabilities strengthen all three learning...

  13. Development of Lumped Element Kinetic Inductance Detectors for NIKA

    CERN Document Server

    Roesch, M; Bideaud, A; Boudou, N; Calvo, M; Cruciani, A; Doyle, S; Leduc, H G; Monfardini, A; Swenson, L; Leclercq, S; Mauskopf, P; Schuster, K F

    2012-01-01

    Lumped-element kinetic inductance detectors(LEKIDs) have recently shown considerable promise as direct absorption mm-wavelength detectors for astronomical applications. One major research thrust within the N\\'eel Iram Kids Array (NIKA) collaboration has been to investigate the suitability of these detectors for deployment at the 30-meter IRAM telescope located on Pico Veleta in Spain. Compared to microwave kinetic inductance detectors (MKID), using quarter wavelength resonators, the resonant circuit of a LEKID consists of a discrete inductance and capacitance coupled to a feedline. A high and constant current density distribution in the inductive part of these resonators makes them very sensitive. Due to only one metal layer on a silicon substrate, the fabrication is relatively easy. In order to optimize the LEKIDs for this application, we have recently probed a wide variety of individual resonator and array parameters through simulation and physical testing. This included determining the optimal feed-line co...

  14. Characterization of an in-vacuum PILATUS 1M detector

    CERN Document Server

    Wernecke, Jan; Müller, Peter; Krumrey, Michael

    2013-01-01

    A dedicated in-vacuum X-ray detector based on the hybrid-pixel PILATUS 1M detector has been installed at the four-crystal monochromator beamline of PTB at the electron storage ring BESSY II in Berlin. Due to its windowless operation, the detector can be used in the entire photon energy range of the beamline from from 10 keV down to 1.75 keV for small-angle X-ray scattering (SAXS) experiments and anomalous SAXS (ASAXS) at absorption edges of light elements. The radiometric and geometric properties of the detector like quantum efficiency, pixel pitch and module alignment have been determined with low uncertainties. First grazing incidence SAXS (GISAXS) results demonstrate the superior resolution in momentum transfer achievable at low photon energies.

  15. Detectors on the drawing board

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Linear collider detector developers inside and outside CERN are tackling the next generation of detector technology. While their focus has centred on high-energy linear collider detectors, their innovative concepts and designs will be applicable to any future detector.   A simulated event display in one of the new generation detectors. “While the LHC experiments remain the pinnacle of detector technology, you may be surprised to realise that the design and expertise behind them is well over 10 years old,” says Lucie Linssen, CERN’s Linear Collider Detector (LCD) project manager whose group is pushing the envelope of detector design. “The next generation of detectors will have to surpass the achievements of the LHC experiments. It’s not an easy task but, by observing detectors currently in operation and exploiting a decade’s worth of technological advancements, we’ve made meaningful progress.” The LCD team is curr...

  16. Towards higher stability of resonant absorption measurements in pulsed plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Britun, Nikolay, E-mail: nikolay.britun@umons.ac.be [Chimie des Interactions Plasma Surface (ChIPS), CIRMAP, Université de Mons, 23 Place du Parc, B-7000 Mons (Belgium); Michiels, Matthieu [Materia Nova Research Center, Parc Initialis, B-7000 Mons (Belgium); Snyders, Rony [Chimie des Interactions Plasma Surface (ChIPS), CIRMAP, Université de Mons, 23 Place du Parc, B-7000 Mons (Belgium); Materia Nova Research Center, Parc Initialis, B-7000 Mons (Belgium)

    2015-12-15

    Possible ways to increase the reliability of time-resolved particle density measurements in pulsed gaseous discharges using resonant absorption spectroscopy are proposed. A special synchronization, called “dynamic source triggering,” between a gated detector and two pulsed discharges, one representing the discharge of interest and another being used as a reference source, is developed. An internal digital delay generator in the intensified charge coupled device camera, used at the same time as a detector, is utilized for this purpose. According to the proposed scheme, the light pulses from the reference source follow the gates of detector, passing through the discharge of interest only when necessary. This allows for the utilization of short-pulse plasmas as reference sources, which is critical for time-resolved absorption analysis of strongly emitting pulsed discharges. In addition to dynamic source triggering, the reliability of absorption measurements can be further increased using simultaneous detection of spectra relevant for absorption method, which is also demonstrated in this work. The proposed methods are illustrated by the time-resolved measurements of the metal atom density in a high-power impulse magnetron sputtering (HiPIMS) discharge, using either a hollow cathode lamp or another HiPIMS discharge as a pulsed reference source.

  17. Monte Carlo simulation of a very high resolution thermal neutron detector composed of glass scintillator microfibers

    CERN Document Server

    Yushou, Song; Zhang, Xiaodong; Hayward, Jason P

    2016-01-01

    In order to develop a high spatial resolution (micron level) thermal neutron detector, a detector assembly composed of cerium doped lithium glass microfibers, each with a diameter of 1\\,$\\mu$m, is proposed, where the neutron absorption location is reconstructed from the observed charged particle products that result from neutron absorption. To suppress the cross talk of the scintillation light, each scintillating fiber is surrounded by air-filled glass capillaries with the same diameter as the fiber. This pattern is repeated to form a bulk microfiber detector. On one end, the surface of the detector is painted with a thin optical reflector to increase the light collection efficiency at the other end. Then the scintillation light emitted by any neutron interaction is transmitted to one end, magnified, and recorded by an intensified CCD camera. A simulation based on the Geant4 toolkit was developed to model this detector. All the relevant physics processes including neutron interaction, scintillation, and optic...

  18. Kinetic Inductance Detectors for X-Ray Spectroscopy

    Science.gov (United States)

    Cecil, T.; Miceli, A.; Gades, L.; Datesman, A.; Quaranta, O.; Yefremenko, V.; Novosad, V.; Mazin, B.

    The lack of efficient x-ray detectors is often the main factor limiting the effective use of ever more powerful synchrotron light sources. Spectroscopic X-ray detectors are used for a wide variety of synchrotron experiments including X-ray micro/nano-probes and X-ray absorption spectroscopy for biology and geophysical applications. The current state-of-art spectroscopic X-ray detectors are semiconductor devices, and their energy resolutions are approaching their theoretical limit of about 100 eV at 6 keV. We describe a detector research and development program to develop the next-generation of high-resolution spectroscopic X-ray detectors using superconducting Kinetic Inductance Detectors (KIDs). With a required energy per charge carrier four orders of magnitude smaller than that of Si, superconducting detectors offer up to two orders of magnitude increase in energy resolution. In addition, KIDs can be optimized for detection of photons ranging in energy from hard X-ray to IR.

  19. Absorption tomography of laser induced plasmas with a large aperture

    CERN Document Server

    Shabanov, Sergei V

    2010-01-01

    An emission tomography of laser-induced plasmas employed in the laser induced breakdown spectroscopy (LIBS) requires long signal integration times during which the plasma cannot be considered stationary. To reduce the integration time, it is proposed to measure a plasma absorption in parallel rays with an aperture that collects light coming from large fractions of the plasma plume at each aperture position. The needed spatial resolution is achieved by a special numerical data processing. Another advantage of the proposed procedure is that inexpensive linear CCD or non-discrete (PMT, photodiode) detectors can be used instead of costly 2-dimensional detectors.

  20. Segmented crystalline scintillators: an initial investigation of high quantum efficiency detectors for megavoltage x-ray imaging.

    Science.gov (United States)

    Sawant, Amit; Antonuk, Larry E; El-Mohri, Youcef; Zhao, Qihua; Li, Yixin; Su, Zhong; Wang, Yi; Yamamoto, Jin; Du, Hong; Cunningham, Ian; Klugerman, Misha; Shah, Kanai

    2005-10-01

    Electronic portal imaging devices (EPIDs) based on indirect detection, active matrix flat panel imagers (AMFPIs) have become the technology of choice for geometric verification of patient localization and dose delivery in external beam radiotherapy. However, current AMFPI EPIDs, which are based on powdered-phosphor screens, make use of only approximately 2% of the incident radiation, thus severely limiting their imaging performance as quantified by the detective quantum efficiency (DQE) (approximately 1%, compared to approximately 75% for kilovoltage AMFPIs). With the rapidly increasing adoption of image-guided techniques in virtually every aspect of radiotherapy, there exist strong incentives to develop high-DQE megavoltage x-ray imagers, capable of providing soft-tissue contrast at very low doses in megavoltage tomographic and, potentially, projection imaging. In this work we present a systematic theoretical and preliminary empirical evaluation of a promising, high-quantum-efficiency, megavoltage x-ray detector design based on a two-dimensional matrix of thick, optically isolated, crystalline scintillator elements. The detector is coupled with an indirect detection-based active matrix array, with the center-to-center spacing of the crystalline elements chosen to match the pitch of the underlying array pixels. Such a design enables the utilization of a significantly larger fraction of the incident radiation (up to 80% for a 6 MV beam), through increases in the thickness of the crystalline elements, without loss of spatial resolution due to the spread of optical photons. Radiation damage studies were performed on test samples of two candidate scintillator materials, CsI(Tl) and BGO, under conditions relevant to radiotherapy imaging. A detailed Monte Carlo-based study was performed in order to examine the signal, spatial spreading, and noise properties of the absorbed energy for several segmented detector configurations. Parameters studied included scintillator

  1. On the time response of background obtained in γ-ray spectroscopy experiments using LaBr3(Ce) detectors with different shielding

    Science.gov (United States)

    Régis, J.-M.; Dannhoff, M.; Jolie, J.; Müller-Gatermann, C.; Saed-Samii, N.

    2016-03-01

    Employing the γ-γ fast-timing technique with LaBr3(Ce) scintillator detectors allows the direct determination of lifetimes of nuclear excited states with a lower limit of about 5 ps. This limit is increased as soon as background is present in the coincidence spectra underneath the full-energy peaks of the γ-γ cascade. Our aim was to identify the components of the γ-ray background by systematic γ-γ fast-timing measurements using different types of γ shielding within a large γ-ray spectrometer. The energy dependent physical zero-time response was measured using background-free full-energy peak events from the 152Eu γ-ray source. This is compared with the time response of the (Compton-) background distribution as obtained using the prompt 60Co γ-ray source. The time response of the typical Compton background is about 15 ps faster than the time response of background-free full-energy peak events. Below about 500 keV, a second type of background contributes by the detection of Compton-scattered γ rays generated in the materials of the spectrometer around the detector. Due to the additional time-of-flight of the Compton-scattered γ rays, this low-energy background is largely delayed. Compared with a bare cylindrical 1.5 in . × 1.5 in . LaBr3(Ce) detector, the BGO-shielded detector in the Compton-suppression mode improves the peak-to-total ratio by a factor of 1.66(5), while the Pb-shielded detector only slightly reduces the low-energy background.

  2. Microwave Kinetic Inductance Detector with Selective Polarization Coupling

    Science.gov (United States)

    Wollack, Edward; U-yen, Kongpop; Stevenson, Thomas; Brown, Ari; Moseley, Samuel; Hsieh, Wen-Ting

    2013-01-01

    A conventional low-noise detector requires a technique to both absorb incident power and convert it to an electrical signal at cryogenic temperatures. This innovation combines low-noise detector and readout functionality into one device while maintaining high absorption, controlled polarization sensitivity, and broadband detection capability. The resulting far-infrared detectors can be read out with a simple approach, which is compact and minimizes thermal loading. The proposed microwave kinetic inductance detector (MKID) consists of three basic elements. The first is the absorptive section in which the incident power is coupled to a superconducting resonator at far-infrared frequency above its superconducting critical frequency (where superconductor becomes normal conductor). This absorber's shape effectively absorbs signals in the desired polarization state and is resonant at the radio frequency (RF) used for readout of the device. Control over the metal film used in the absorber allows realization of structures with either a 50% broadband or 100% resonance absorptance over a 30% fractional bandwidth. The second element is a microwave resonator - which is realized from the thin metal films used to make the absorber as transmission lines - whose resonance frequency changes due to a variation in its kinetic inductance. The resonator's kinetic inductance is a function of the power absorbed by the device. A low-loss dielectric (mono-crystalline silicon) is used in a parallel-plate transmission line structure to realize the desired superconducting resonators. There is negligible coupling among the adjacent elements used to define the polarization sensitivity of each detector. The final component of the device is a microwave transmission line, which is coupled to the resonator, and allows detection of changes in resonance frequency for each detector in the focal plane array. The spiral shape of the detector's absorber allows incident power with two polarizations to

  3. The ZEUS microvertex detector

    CERN Document Server

    Garfagnini, A

    1999-01-01

    A new vertex detector for the ZEUS experiment at HERA will be installed during the 1999-2000 shutdown, for the high-luminosity runs of HERA. It will allow to reconstruct secondary vertex tracks, coming from the decay of long-lived particles with a lifetime of about 10 sup - sup 1 sup 2 s, and improve the global momentum resolution of the tracking system. The interaction region will be surrounded with single-sided silicon strip detectors, with capacitive charge division: three double layers in the central region (600 detectors), and 4 'wheels' in the forward region (112 silicon planes). Due to the high number of readout channels, 512 readout strips per silicon plane in the barrel region and 480 in the forward part, and the large coverage of the vertex detector (almost 1 m long), the front-end electronics has to be placed on top of the detectors and has to be radiation tolerant since doses up to 2 kGy are expected near the interaction region. The HELIX chip has been chosen as analog chip with a low-noise, charg...

  4. Detectors in Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Blaj, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carini, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carron, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Haller, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hart, P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hasi, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Herrmann, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Kenney, C. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Segal, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Tomada, A. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-06

    Free Electron Lasers opened a new window on imaging the motion of atoms and molecules. At SLAC, FEL experiments are performed at LCLS using 120Hz pulses with 1012 - 1013 photons in 10 femtoseconds (billions of times brighter than the most powerful synchrotrons). This extreme detection environment raises unique challenges, from obvious to surprising. Radiation damage is a constant threat due to accidental exposure to insufficiently attenuated beam, focused beam and formation of ice crystals reflecting the beam onto the detector. Often high power optical lasers are also used (e.g., 25TW), increasing the risk of damage or impeding data acquisition through electromagnetic pulses (EMP). The sample can contaminate the detector surface or even produce shrapnel damage. Some experiments require ultra high vacuum (UHV) with strict design, surface contamination and cooling requirements - also for detectors. The setup is often changed between or during experiments with short turnaround times, risking mechanical and ESD damage, requiring work planning, training of operators and sometimes continuous participation of the LCLS Detector Group in the experiments. The detectors used most often at LCLS are CSPAD cameras for hard x-rays and pnCCDs for soft x-rays.

  5. Central cooling: absorptive chillers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1977-08-01

    This technology evaluation covers commercially available single-effect, lithium-bromide absorption chillers ranging in nominal cooling capacities of 3 to 1,660 tons and double-effect lithium-bromide chillers from 385 to 1,060 tons. The nominal COP measured at operating conditions of 12 psig input steam for the single-effect machine, 85/sup 0/ entering condenser water, and 44/sup 0/F exiting chilled-water, ranges from 0.6 to 0.65. The nominal COP for the double-effect machine varies from 1.0 to 1.15 with 144 psig entering steam. Data are provided to estimate absorption-chiller performance at off-nominal operating conditions. The part-load performance curves along with cost estimating functions help the system design engineer select absorption equipment for a particular application based on life-cycle costs. Several suggestions are offered which may be useful for interfacing an absorption chiller with the remaining Integrated Community Energy System. The ammonia-water absorption chillers are not considered to be readily available technology for ICES application; therefore, performance and cost data on them are not included in this evaluation.

  6. OPERA: Electronic Detector

    CERN Document Server

    Jollet, C

    2010-01-01

    OPERA is an hybrid detector for the ni-tau appearance search in a direct way, and the Electronic Detectors (ED) have the crucial role of triggerring for the neutrino events and of localizing such an interaction inside the target. Another very important task of the ED is to identify the muon since only a correct matching of such a track with a track in the emulsion connected to the vertex of the event allows to reduce the charm background to the desired level. The ED, fully working since 2006, consist of a target tracker (scintillator strips) and a spectrometer (RPC and drift tubes). The different sub-detectors are de- scribed in the poster, as well as their performance both on Monte Carlo (MC) and real data.

  7. Transition Radiation Detectors

    CERN Document Server

    Andronic, A

    2012-01-01

    We review the basic features of transition radiation and how they are used for the design of modern Transition Radiation Detectors (TRD). The discussion will include the various realizations of radiators as well as a discussion of the detection media and aspects of detector construction. With regard to particle identification we assess the different methods for efficient discrimination of different particles and outline the methods for the quantification of this property. Since a number of comprehensive reviews already exist, we predominantly focus on the detectors currently operated at the LHC. To a lesser extent we also cover some other TRDs, which are planned or are currently being operated in balloon or space-borne astro-particle physics experiments.

  8. The LHCb Detector Upgrade

    CERN Document Server

    Schindler, H

    2013-01-01

    The LHCb collaboration presented a Letter of Intent (LOI) to the LHCC in March 2011 for a major upgrading of the detector during Long Shutdown 2 (2018) and intends to collect a data sample of 50/fb in the LHC and High-Luminosity-LHC eras. The aim is to operate the experiment at an instantaneous luminosity 2.5 times above the present operational luminosity, which has already been pushed to twice the design value. Reading out the detector at 40MHz allows to increase the trigger efficiencies especially for the hadronic decay modes. The physics case and the strategy for the upgrade have been endorsed by the LHCC. This paper presents briefly the physics motivations for the LHCb upgrade and the proposed changes to the detector and trigger.

  9. JSATS Detector Field Manual

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eric Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flory, Adam E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamarche, Brian L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-06-01

    The Juvenile Salmon Acoustic Telemetry System (JSATS) Detector is a software and hardware system that captures JSATS Acoustic Micro Transmitter (AMT) signals. The system uses hydrophones to capture acoustic signals in the water. This analog signal is then amplified and processed by the Analog to Digital Converter (ADC) and Digital Signal Processor (DSP) board in the computer. This board digitizes and processes the acoustic signal to determine if a possible JSATS tag is present. With this detection, the data will be saved to the computer for further analysis. This document details the features and functionality of the JSATS Detector software. The document covers how to install the software, setup and run the detector software. The document will also go over the raw binary waveform file format and CSV files containing RMS values

  10. JSATS Detector Field Manual

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eric Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flory, Adam E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamarche, Brian L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-06-01

    The Juvenile Salmon Acoustic Telemetry System (JSATS) Detector is a software and hardware system that captures JSATS Acoustic Micro Transmitter (AMT) signals. The system uses hydrophones to capture acoustic signals in the water. This analog signal is then amplified and processed by the Analog to Digital Converter (ADC) and Digital Signal Processor (DSP) board in the computer. This board digitizes and processes the acoustic signal to determine if a possible JSATS tag is present. With this detection, the data will be saved to the computer for further analysis. This document details the features and functionality of the JSATS Detector software. The document covers how to install the software, setup and run the detector software. The document will also go over the raw binary waveform file format and CSV files containing RMS values

  11. Cryogenic Tracking Detectors

    CERN Multimedia

    Luukka, P R; Tuominen, E M; Mikuz, M

    2002-01-01

    The recent advances in Si and diamond detector technology give hope of a simple solution to the radiation hardness problem for vertex trackers at the LHC. In particular, we have recently demonstrated that operating a heavily irradiated Si detector at liquid nitrogen (LN$_2$) temperature results in significant recovery of Charge Collection Efficiency (CCE). Among other potential benefits of operation at cryogenic temperatures are the use of large low-resistivity wafers, simple processing, higher and faster electrical signal because of higher mobility and drift velocity of carriers, and lower noise of the readout circuit. A substantial reduction in sensor cost could result The first goal of the approved extension of the RD39 program is to demonstrate that irradiation at low temperature in situ during operation does not affect the results obtained so far by cooling detectors which were irradiated at room temperature. In particular we shall concentrate on processes and materials that could significantly reduce th...

  12. The AFP Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

  13. ALICE Transition Radiation Detector

    CERN Multimedia

    Pachmayer, Y

    2013-01-01

    The Transition Radiation Detector (TRD) is the main electron detector in ALICE. In conduction with the TPC and the ITS, it provides the necessary electron identification capability to study: - Production of light and heavy vector mesons as well as the continuum in the di-electron channel, - Semi leptonic decays of hadrons with open charm and open beauty via the single-electron channel using the displaced vertex information provided by the ITS, - Correlated DD and BB pairs via coincidences of electrons in the central barrel and muons in the forward muon arm, - Jets with high Pτ tracks in one single TRD stack.

  14. Edgeless silicon pad detectors

    Science.gov (United States)

    Perea Solano, B.; Abreu, M. C.; Avati, V.; Boccali, T.; Boccone, V.; Bozzo, M.; Capra, R.; Casagrande, L.; Chen, W.; Eggert, K.; Heijne, E.; Klauke, S.; Li, Z.; Mäki, T.; Mirabito, L.; Morelli, A.; Niinikoski, T. O.; Oljemark, F.; Palmieri, V. G.; Rato Mendes, P.; Rodrigues, S.; Siegrist, P.; Silvestris, L.; Sousa, P.; Tapprogge, S.; Trocmé, B.

    2006-05-01

    We report measurements in a high-energy pion beam of the sensitivity of the edge region in "edgeless" planar silicon pad diode detectors diced through their contact implants. A large surface current on such an edge prevents the normal reverse biasing of the device, but the current can be sufficiently reduced by the use of a suitable cutting method, followed by edge treatment, and by operating the detector at low temperature. The depth of the dead layer at the diced edge is measured to be (12.5±8 stat..±6 syst.) μm.

  15. Edgeless silicon pad detectors

    Energy Technology Data Exchange (ETDEWEB)

    Perea Solano, B. [CERN, CH-1211 Geneva 23 (Switzerland)]. E-mail: blanca.perea.solano@cern.ch; Abreu, M.C. [LIP and University of Algarve, 8000 Faro (Portugal); Avati, V. [CERN, CH-1211 Geneva 23 (Switzerland); Boccali, T. [INFN Sez. di Pisa and Scuola Normale Superiore, Pisa (Italy); Boccone, V. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Bozzo, M. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Capra, R. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Casagrande, L. [INFN Sez. di Roma 2 and Universita di Roma 2, Rome (Italy); Chen, W. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Eggert, K. [CERN, CH-1211 Geneva 23 (Switzerland); Heijne, E. [CERN, CH-1211 Geneva 23 (Switzerland); Klauke, S. [CERN, CH-1211 Geneva 23 (Switzerland); Li, Z. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Maeki, T. [Helsinki Institute of Physics, Helsinki (Finland); Mirabito, L. [CERN, CH-1211 Geneva 23 (Switzerland); Morelli, A. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Niinikoski, T.O. [CERN, CH-1211 Geneva 23 (Switzerland); Oljemark, F. [Helsinki Institute of Physics, Helsinki (Finland); Palmieri, V.G. [Helsinki Institute of Physics, Helsinki (Finland); Rato Mendes, P. [LIP and University of Algarve, 8000 Faro (Portugal); Rodrigues, S. [LIP and University of Algarve, 8000 Faro (Portugal); Siegrist, P. [CERN, CH-1211 Geneva 23 (Switzerland); Silvestris, L. [INFN Sez. Di Bari, Bari (Italy); Sousa, P. [LIP and University of Algarve, 8000 Faro (Portugal); Tapprogge, S. [Helsinki Institute of Physics, Helsinki (Finland); Trocme, B. [Institut de Physique Nucleaire, Villeurbanne (France)

    2006-05-01

    We report measurements in a high-energy pion beam of the sensitivity of the edge region in 'edgeless' planar silicon pad diode detectors diced through their contact implants. A large surface current on such an edge prevents the normal reverse biasing of the device, but the current can be sufficiently reduced by the use of a suitable cutting method, followed by edge treatment, and by operating the detector at low temperature. The depth of the dead layer at the diced edge is measured to be (12.5{+-}8{sub stat.}.{+-}6{sub syst.}) {mu}m.

  16. Radiation Detectors and Art

    Science.gov (United States)

    Denker, Andrea

    The use of radiation detectors in the analysis of art objects represents a very special application in a true interdisciplinary field. Radiation detectors employed in this field detect, e.g., x-rays, γ-rays, β particles, and protons. Analyzed materials range from stones, metals, over porcelain to paintings. The available nondestructive and noninvasive analytical methods cover a broad range of techniques. Hence, for the sake of brevity, this chapter will concentrate on few techniques: Proton Induced X-ray Emission (PIXE) and Proton Induced γ-ray Emission (PIGE).

  17. Infrared Responsivity of a Pyroelectric Detector with a Single-Wall Carbon Nanotube Coating

    Energy Technology Data Exchange (ETDEWEB)

    Theocharous, E.; Engtrakul, C.; Dillon, A. C.; Lehman, J.

    2008-08-01

    The performance of a 10 mm diameter pyroelectric detector coated with a single-wall carbon nanotube (SWCNT) was evaluated in the 0.8 to 20 {micro}m wavelength range. The relative spectral responsivity of this detector exhibits significant fluctuations over the wavelength range examined. This is consistent with independent absorbance measurements, which show that SWCNTs exhibit selective absorption bands in the visible and near-infrared. The performance of the detector in terms of noise equivalent power and detectivity in wavelength regions of high coating absorptivity was comparable with gold-black-coated pyroelectric detectors based on 50 {micro}m thick LiTaO{sub 3} crystals. The response of this detector was shown to be nonlinear for DC equivalent photocurrents >10{sup -9} A, and its spatial uniformity of response was comparable with other pyroelectric detectors utilizing gold-black coatings. The nonuniform spectral responsivity exhibited by the SWCNT-coated detector is expected to severely restrict the use of SWCNTs as black coatings for thermal detectors. However, the deposition of SWCNT coatings on a pyroelectric crystal followed by the study of the prominence of the spectral features in the relative spectral responsivity of the resultant pyroelectric detectors is shown to provide an effective method for quantifying the impurity content in SWCNT samples.

  18. Differential optical absorption spectrometer for measurement of tropospheric pollutants.

    Science.gov (United States)

    Evangelisti, F; Baroncelli, A; Bonasoni, P; Giovanelli, G; Ravegnani, F

    1995-05-20

    Our institute has recently developed a differential optical absorption spectrometry system called the gas analyzer spectrometer correlating optical absorption differences (GASCOAD), which features as a detector a linear image sensor that uses an artificial light source for long-path tropospheric-pollution monitoring. The GASCOAD, its method of eliminating interference from background sky light, and subsequent spectral analysis are reported and discussed. The spectrometer was used from 7 to 22 February 1993 in Milan, a heavily polluted metropolitan area, to measure the concentrations of SO(2), NO(2), O(3), and HNO(2) averaged over a 1.7-km horizontal light path. The findings are reported and briefly discussed.

  19. Alternative method for thermal neutron flux measurements based on common boric acid as converter and Lr-15 detectors

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, D.; Greaves, E. D.; Sajo B, L.; Barros, H. [Universidad Simon Bolivar, Laboratorio de Fisica Nuclear, Apdo. Postal 89000, Caracas (Venezuela, Bolivarian Republic of); Ingles, R. [Universidad Nacional de San Antonio Abad del Cusco, Av. de la Cultura No. 733, Cusco (Peru)

    2010-02-15

    A method to determine the flux and angular distribution of thermal neutrons with the use of Lr-115 detectors was developed. The use of the Lr-115 detector involves the exposure of a pressed boric acid sample (tablet) as a target, in tight contact with the track detector, to a flux of thermalized neutrons. The self-absorption effects in thin films or foil type thermal neutron detectors can be neglected by using the Lr-115 detector and boric acid tablet setup to operate via backside irradiation. The energy window and the critical angle-residual energy curve were determined by comparisons between the experimental and simulated track parameters. A computer program was developed to calculate the detector registration efficiency, so that the thermal neutron flux can be calculated from the track densities induced in the Lr-115 detector using the derived empirical formula. The proposed setup can serves as directional detector of thermal neutrons. (Author)

  20. X-ray imaging with the PILATUS 100k detector

    DEFF Research Database (Denmark)

    Bech, Martin; Bunk, O.; David, C.;

    2008-01-01

    We report on the application of the PILATUS 100K pixel detector for medical imaging. Experimental results are presented in the form of X-ray radiographs using standard X-ray absorption contrast and a recently developed phase contrast imaging method. The results obtained with the PILATUS detector...... are compared to results obtained with a conventional X-ray imaging system consisting of an X-ray scintillation screen, lens optics, and a charge coupled device. Finally, the results for both systems are discussed more quantitatively based on an image power spectrum analysis. Udgivelsesdato: April...

  1. The Upgraded D0 Detector

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, D L; Adams, M; Adams, T; Agelou, M; Agram, J L; Ahmed, S N; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, J T; Anderson, S; Andrieu, B; Angstadt, R; Anosov, V; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Babukhadia, L; Bacon, Trevor C; Badaud, F; Baden, A; Baffioni, S; Bagby, L; Baldin, B; Balm, P W; Banerjee, P; Banerjee, S; Barberis, E; Bardon, O; Barg, W; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bhattacharjee, M; Baturitsky, M A; Bauer, D; Bean, A; Baumbaugh, B; Beauceron, S; Begalli, M; Beaudette, F; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Besson, A; Beuselinck, R; Beutel, D; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Bishoff, A; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Bockenthein, E; Bodyagin, V; Böhnlein, A; Boeriu, O; Bolton, T A; Bonamy, P; Bonifas, D; Borcherding, F; Borissov, G; Bos, K; Bose, T; Boswell, C; Bowden, M; Brandt, A; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, D; Butler, J M; Cammin, J; Caron, S; Bystrický, J; Canal, L; Canelli, F; Carvalho, W; Casey, B C K; Casey, D; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Chi, E; Chiche, R; Cho, D K; Choate, R; Choi, S; Choudhary, B; Chopra, S; Christenson, J H; Christiansen, T; Christofek, L; Churin, I; Cisko, G; Claes, D; Clark, A R; Clement, B; Clément, C; Coadou, Y; Colling, D J; Coney, L; Connolly, B; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M C; Cox, B; Crepe-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; Da Motta, H; Das, M; Davies, B; Davies, G; Davis, G A; Davis, W; De, K; de Jong, P; De Jong, S J; De La Cruz-Burelo, E; de La Taille, C; De Oliveira Martins, C; Dean, S; Degenhardt, J D; Déliot, F; Delsart, P A; Del Signore, K; De Maat, R; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doets, M; Doidge, M; Dong, H; Doulas, S; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dvornikov, O; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fagan, J; Fast, J; Fatakia, S N; Fein, D; Feligioni, L; Ferapontov, A V; Ferbel, T; Ferreira, M J; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Fitzpatrick, T; Flattum, E; Fleuret, F; Flores, R; Foglesong, J; Fortner, M; Fox, H; Franklin, C; Freeman, W; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Gao, M; García, C; García-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Yu; Gillberg, D; Geurkov, G; Ginther, G; Gobbi, B; Goldmann, K; Golling, T; Gollub, N; Golovtsov, V L; Gómez, B; Gómez, G; Gómez, R; Goodwin, R W; Gornushkin, Y; Gounder, K; Goussiou, A; Graham, D; Graham, G; Grannis, P D; Gray, K; Greder, S; Green, D R; Green, J; Green, J A; Greenlee, H; Greenwood, Z D; Gregores, E M; Grinstein, S; Gris, P; Grivaz, J F; Groer, L; Grünendahl, S; Grünewald, M W; Gu, W; Guglielmo, J; Sen-Gupta, A; Gurzhev, S N; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Haggard, E; Haggerty, H; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hance, R; Hanagaki, K; Hanlet, P; Hansen, S; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, C; Hays, J; Hazen, E; Hebbeker, T; Hebert, C; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Hou, S; Houben, P; Hu, Y; Huang, J; Huang, Y; Hynek, V; Huffman, D; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jacquier, Y; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jayanti, R; Jenkins, A; Jesik, R; Jiang, Y; Johns, K; Johnson, M; Johnson, P; Jonckheere, A; Jonsson, P; Jöstlein, H; Jouravlev, N I; Juárez, M; Juste, A; Kaan, A P; Kado, M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Kalmani, S D; Karmanov, D; Kasper, J; Katsanos, I; Kau, D; Kaur, R; Ke, Z; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Kim, H; Kim, K H; Kim, T J; Kirsch, N; Klima, B; Klute, M; Kohli, J M; Konrath, J P; Komissarov, E V; Kopal, M; Korablev, V M; Kostritskii, A V; Kotcher, J; Kothari, B; Kotwal, A V; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Kuznetsov, O; Krane, J; Kravchuk, N; Krempetz, K; Krider, J; Krishnaswamy, M R; Krzywdzinski, S; Kubantsev, M A; Kubinski, R; Kuchinsky, N; Kuleshov, S; Kulik, Y; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Kuznetsov, V E; Kwarciany, R; Lager, S; Lahrichi, N; Landsberg, G L; Larwill, M; Laurens, P; Lavigne, B; Lazoflores, J; Le Bihan, A C; Le Meur, G; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Leggett, C; Lehner, F; Leitner, R; Leonidopoulos, C; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Li, X; Lima, J G R; Lincoln, D; Lindenmeyer, C; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Litmaath, M; Lizarazo, J; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lü, J; Lubatti, H J; Lucotte, A; Lueking, L; Luo, C; Lynker, M; Lyon, A L; Machado, E; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A M; Maity, M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Manakov, V; Mao, H S; Maravin, Y; Markley, D; Markus, M; Marshall, T; Martens, M; Martin, M; Martin-Chassard, G; Mattingly, S E K; Matulik, M; Mayorov, A A; McCarthy, R; McCroskey, R; McKenna, M; McMahon, T; Meder, D; Melanson, H L; Melnitchouk, A S; Mendes, A; Mendoza, D; Mendoza, L; Meng, X; Merekov, Y P; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miao, C; Miettinen, H; Mihalcea, D; Mikhailov, V; Miller, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mostafa, M; Moua, S; Mulders, M; Mundim, L; Mutaf, Y D; Nagaraj, P; Nagy, E; Naimuddin, M; Nang, F; Narain, M; Narasimhan, V S; Narayanan, A; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neuenschwander, R T; Neustroev, P; Nöding, C; Nomerotski, A; Novaes, S F; Nozdrin, A; Nunnemann, T; Nurczyk, A; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Olis, D; Oliveira, N; Olivier, B; Olsen, J; Oshima, N; Oshinowo, B O; Oteroy-Garzon, G J; Padley, P; Papageorgiou, K; Parashar, N; Park, J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Pérez, E; Peters, O; Petroff, P; Petteni, M; Phaf, L; Piegaia, R; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Polosov, P; Pope, B G; Popkov, E; Porokhovoy, S; Prado da Silva, W L; Pritchard, W; Prokhorov, I; Prosper, H B; Protopopescu, S D; Przybycien, M B; Qian, J; Quadt, A; Quinn, B; Ramberg, E; Ramirez-Gomez, R; Rani, K J; Ranjan, K; Rao, M V S; Rapidis, P A; Rapisarda, S; Raskowski, J; Ratoff, P N; Ray, R E; Reay, N W; Rechenmacher, R; Reddy, L V; Regan, T; Renardy, J F; Reucroft, S; Rha, J; Ridel, M; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Roco, M T; Rotolo, C; Royon, C; Rubinov, P; Ruchti, R; Rucinski, R; Rud, V I; Rusakovich, N; Russo, P; Sabirov, B; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Satyanarayana, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schukin, A A; Schwartzman, A; Schwienhorst, R; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shankar, H C; Shary, V; Shchukin, A A; Sheahan, P; Shephard, W D; Shivpuri, R K; Shishkin, A A; Shpakov, D; Shupe, M; Sidwell, R A; Simák, V; Sirotenko, V I; Skow, D; Skubic, P L; Slattery, P F; Smith, D E; Smith, R P; Smolek, K; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Song, Y; Sonnenschein, L; Sopczak, A; Sorin, V; Sosebee, M; Soustruznik, K; Souza, M; Spartana, N; Spurlock, B; Stanton, N R; Stark, J; Steele, J; Stefanik, A; Steinberg, J L; Steinbruck, G; Stevenson, K; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Sznajder, A; Talby, M; Tentindo-Repond, S; Tamburello, P; Taylor, W; Telford, P; Temple, J; Terentyev, N K; Teterin, V; Thomas, E; Thompson, J; Thooris, B; Titov, M; Toback, D; Tokmenin, V V; Tolian, C; Tomoto, M; Tompkins, D; Toole, T; Torborg, J; Touze, F; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Trippe, T G; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Utes, M; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; Van den Berg, P J; Van Gemmeren, P; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Vaz, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Vigneault, M; Villeneuve-Séguier, F; Vishwanath, P R; Vlimant, J R; Von Törne, E; Vorobyov, A; Vreeswijk, M; Vu-Anh, T; Vysotsky, V S; Wahl, H D; Walker, R; Wallace, N; Wang, L; Wang, Z M; Warchol, J; Warsinsky, M; Watts, G; Wayne, M; Weber, M; Weerts, H; Wegner, M; Wermes, N; Wetstein, M; White, A; White, V; Whiteson, D; Wicke, D; Wijnen, T A M; Wijngaarden, D A; Wilcer, N; Willutzki, H; Wilson, G W; Wimpenny, S J; Wittlin, J; Wlodek, T; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Wu, Z; Xie, Y; Xu, Q; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yarema, R J; Yasuda, T; Yatsunenko, Y A; Yen, Y; Yip, K; Yoo, H D; Yoffe, F; Youn, S W; Yu, J; Yurkewicz, A; Zabi, A; Zanabria, M; Zatserklyaniy, A; Zdrazil, M; Zeitnitz, C; Zhang, B; Zhang, D; Zhang, X; Zhao, T; Zhao, Z; Zheng, H; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zitoun, R; Zmuda, T; Zutshi, V; Zviagintsev, S; Zverev, E G; Zylberstejn, A

    2005-01-01

    The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.

  2. The Upgraded D0 detector

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, D.L.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahmed, S.N.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G.A.; Anastasoaie, M.; Andeen, T.; Anderson, J.T.; Anderson, S.; /Buenos Aires U. /Rio de Janeiro, CBPF /Sao Paulo, IFT /Alberta U.

    2005-07-01

    The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.

  3. Status of the KEDR detector

    CERN Document Server

    Anashin, V V; Baibusinov, B O; Balashov, V; Baldin, E M; Barkov, L M; Barladyan, A K; Barnyakov, M Y; Baru, S E; Bedny, I; Beilin, D M; Blinov, A E; Blinov, V E; Bondarev, D V; Bondar, A E; Buzykaev, A R; Cantoni, P; Chilingarov, A G; Dneprovsky, L V; Eidelman, S I; Epifanov, D A; Frabetti, P L; Gaidarev, P B; Groshev, V R; Karpov, S V; Kiselev, V A; Klimenko, S G; Kolachev, G M; Kononov, S A; Kozlov, V N; Kravchenko, E A; Kulikov, V F; Kurdadze, L M; Kuzmin, A S; Kuznecov, S A; Lanni, F; Lelchuk, M Y; Leontiev, L A; Levichev, E B; Malyshev, V M; Manfredi, P F; Maslennikov, A L; Minakov, G D; Nagaslaev, V P; Naumenkov, A I; Nikitin, S A; Nomerotski, A; Onuchin, A P; Oreshkin, S B; Ovechkin, R; Palombo, F; Peleganchuk, S V; Petrosyan, S S; Pivovarov, S V; Poluektov, A O; Pospelov, G E; Protopopov, I Ya; Re, V; Romanov, L V; Root, N I; Ruban, A A; Savinov, G A; Shamov, A G; Shatilov, D; Shubin, M A; Shusharo, A I; Shwartz, B A; Sidorov, V A; Skovpen, Y I; Smakhtin, V P; Snopkov, R G; Sokolov, A V; Soukharev, A M; Talyshev, A A; Tayursky, V A; Telnov, V I; Tikhonov, Yu A; Todyshev, K Y; Usov, Y V; Vorobyev, A I; Yushkov, A N; Zatcepin, A V; Zhilich, V N

    2002-01-01

    KEDR is a general-purpose detector for experiments at the VEPP-4M e sup + e sup - -collider in the energy range 2E=2.0-12 GeV. All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/PSI meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.

  4. Status of the KEDR detector

    Energy Technology Data Exchange (ETDEWEB)

    Anashin, V.V.; Aulchenko, V.M.; Baibusinov, B.O.; Balashov, V.; Baldin, E.M.; Barkov, L.M.; Barladyan, A.K.; Barnyakov, M.Yu.; Baru, S.E.; Bedny, I.V.; Beilin, D.M.; Blinov, A.E.; Blinov, V.E.; Bondarev, D.V.; Bondar, A.E.; Buzykaev, A.R.; Cantoni, P.; Chilingarov, A.G.; Dneprovsky, L.V.; Eidelman, S.I.; Epifanov, D.A.; Frabetti, P.L.; Gaidarev, P.B.; Groshev, V.R.; Karpov, S.V.; Kiselev, V.A.; Klimenko, S.G.; Kolachev, G.M.; Kononov, S.A.; Kozlov, V.N.; Kravchenko, E.A.; Kulikov, V.F.; Kurdadze, L.M.; Kuzmin, A.S.; Kuznecov, S.A.; Lanni, F.; Lelchuk, M.Yu.; Leontiev, L.A.; Levichev, E.B.; Malyshev, V.M.; Manfredi, P.F.; Maslennikov, A.L.; Minakov, G.D.; Nagaslaev, V.P.; Naumenkov, A.; Nikitin, S.A.; Nomerotsky, A.; Onuchin, A.P.; Oreshkin, S.B.; Ovechkin, R.; Palombo, F.; Peleganchuk, S.V.; Petrosyan, S.S.; Pivovarov, S.V.; Poluektov, A.O.; Pospelov, G.E.; Protopopov, I.Ya.; Re, V.; Romanov, L.V.; Root, N.I.; Ruban, A.A.; Savinov, G.A.; Shamov, A.G.; Shatilov, D.; Shubin, M.A.; Shusharo, A.I.; Shwartz, B.A.; Sidorov, V.A.; Skovpen, Yu.I.; Smakhtin, V.P.; Snopkov, R.G.; Sokolov, A.V.; Soukharev, A.M.; Talyshev, A.A.; Tayursky, V.A.; Telnov, V.I.; Tikhonov, Yu.A. E-mail: tikhonov@cppm.in2p3.fr; Todyshev, K.Yu.; Usov, Yu.V.; Vorobyev, A.I.; Yushkov, A.N.; Zatcepin, A.V.; Zhilich, V.N

    2002-02-01

    KEDR is a general-purpose detector for experiments at the VEPP-4M e{sup +}e{sup -}-collider in the energy range 2E=2.0-12 GeV. All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/{psi} meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.

  5. A Balloon-borne Measurement of High Latitude Atmospheric Neutrons Using a LiCAF Neutron Detector

    CERN Document Server

    Kole, Merlin; Fukuda, Kentaro; Ishizu, Sumito; Jackson, Miranda; Kamae, Tune; Kawaguchi, Noriaki; Kawano, Takafumi; Kiss, Mózsi; Moretti, Elena; Salinas, Maria Fernanda Muñoz; Pearce, Mark; Rydström, Stefan; Takahashi, Hiromitsu; Yanagida, Takayuki

    2013-01-01

    PoGOLino is a scintillator-based neutron detector. Its main purpose is to provide data on the neutron flux in the upper stratosphere at high latitudes at thermal and nonthermal energies for the PoGOLite instrument. PoGOLite is a balloon borne hard X-ray polarimeter for which the main source of background stems from high energy neutrons. No measurements of the neutron environment for the planned flight latitude and altitude exist. Furthermore this neutron environment changes with altitude, latitude and solar activity, three variables that will vary throughout the PoGOLite flight. PoGOLino was developed to study the neutron environment and the influences from these three variables upon it. PoGOLino consists of two Europium doped Lithium Calcium Aluminium Fluoride (Eu:LiCAF) scintillators, each of which is sandwiched between 2 Bismuth Germanium Oxide (BGO) scintillating crystals, which serve to veto signals produced by gamma-rays and charged particles. This allows the neutron flux to be measured even in high rad...

  6. Analysis of lichen substances including triterpenoids by high performance liquid chromatography with a differential refractive index detector and a photodiode array detector

    Institute of Scientific and Technical Information of China (English)

    Hikari SATO; Kojiro HARA; Masashi KOMINE; Yoshikazu YAMAMOTO

    2011-01-01

    A new method for analysis of lichen triterpenoids was established using high performance liquid chromatography with the combination of a differential refractive index detector (RID) and a photodiode array detector (PDA).It is proved that this method was convenient to detect and identify aromatic and aliphatic lichen substances; it enabled quantitative analysis of substances having no or less absorption of ultraviolet rays such as triterpenoids.In addition,they can be measured in high accuracy compared with the TLC method.

  7. Constraining solar hidden photons using HPGe detector

    Energy Technology Data Exchange (ETDEWEB)

    Horvat, R.; Kekez, D., E-mail: Dalibor.Kekez@irb.hr; Krčmar, M.; Krečak, Z.; Ljubičić, A.

    2013-04-25

    In this Letter we report on the results of our search for photons from a U(1) gauge factor in the hidden sector of the full theory. With our experimental setup we observe the single spectrum in a HPGe detector arising as a result of the photoelectric-like absorption of hidden photons emitted from the Sun on germanium atoms inside the detector. The main ingredient of the theory used in our analysis, a severely constrained kinetic mixing from the two U(1) gauge factors and massive hidden photons, entails both photon into hidden state oscillations and a minuscule coupling of hidden photons to visible matter, of which the latter our experimental setup has been designed to observe. On a theoretical side, full account was taken of the effects of refraction and damping of photons while propagating in Sun's interior as well as in the detector. We exclude hidden photons with kinetic couplings χ>(2.2×10{sup −13}–3×10{sup −7}) in the mass region 0.2 eV≲m{sub γ{sup ′}}≲30 keV. Our constraints on the mixing parameter χ in the mass region from 20 eV up to 15 keV prove even slightly better then those obtained recently by using data from the CAST experiment, albeit still somewhat weaker than those obtained from solar and HB stars lifetime arguments.

  8. Fast Detector Simulation Using Lelaps, Detector Descriptions in GODL

    Energy Technology Data Exchange (ETDEWEB)

    Langeveld, Willy; /SLAC

    2005-07-06

    Lelaps is a fast detector simulation program which reads StdHep generator files and produces SIO or LCIO output files. It swims particles through detectors taking into account magnetic fields, multiple scattering and dE/dx energy loss. It simulates parameterized showers in EM and hadronic calorimeters and supports gamma conversions and decays. In addition to three built-in detector configurations, detector descriptions can also be read from files in the new GODL file format.

  9. Chemical Absorption Materials

    DEFF Research Database (Denmark)

    Thomsen, Kaj

    2011-01-01

    Chemical absorption materials that potentially can be used for post combustion carbon dioxide capture are discussed. They fall into five groups, alkanolamines, alkali carbonates, ammonia, amino acid salts, and ionic liquids. The chemistry of the materials is discussed and advantages and drawbacks...... are mentioned. References to review papers, papers with experimental data, and papers describing the thermodynamic modelling of the systems are given....

  10. Microtextured Silicon Surfaces for Detectors, Sensors & Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Carey, JE; Mazur, E

    2005-05-19

    With support from this award we studied a novel silicon microtexturing process and its application in silicon-based infrared photodetectors. By irradiating the surface of a silicon wafer with intense femtosecond laser pulses in the presence of certain gases or liquids, the originally shiny, flat surface is transformed into a dark array of microstructures. The resulting microtextured surface has near-unity absorption from near-ultraviolet to infrared wavelengths well below the band gap. The high, broad absorption of microtextured silicon could enable the production of silicon-based photodiodes for use as inexpensive, room-temperature multi-spectral photodetectors. Such detectors would find use in numerous applications including environmental sensors, solar energy, and infrared imaging. The goals of this study were to learn about microtextured surfaces and then develop and test prototype silicon detectors for the visible and infrared. We were extremely successful in achieving our goals. During the first two years of this award, we learned a great deal about how microtextured surfaces form and what leads to their remarkable optical properties. We used this knowledge to build prototype detectors with high sensitivity in both the visible and in the near-infrared. We obtained room-temperature responsivities as high as 100 A/W at 1064 nm, two orders of magnitude higher than standard silicon photodiodes. For wavelengths below the band gap, we obtained responsivities as high as 50 mA/W at 1330 nm and 35 mA/W at 1550 nm, close to the responsivity of InGaAs photodiodes and five orders of magnitude higher than silicon devices in this wavelength region.

  11. Monte Carlo analysis of megavoltage x-ray interaction-induced signal and noise in cadmium tungstate detectors for cargo container inspection

    Science.gov (United States)

    Kim, J.; Park, J.; Kim, J.; Kim, D. W.; Yun, S.; Lim, C. H.; Kim, H. K.

    2016-11-01

    For the purpose of designing an x-ray detector system for cargo container inspection, we have investigated the energy-absorption signal and noise in CdWO4 detectors for megavoltage x-ray photons. We describe the signal and noise measures, such as quantum efficiency, average energy absorption, Swank noise factor, and detective quantum efficiency (DQE), in terms of energy moments of absorbed energy distributions (AEDs) in a detector. The AED is determined by using a Monte Carlo simulation. The results show that the signal-related measures increase with detector thickness. However, the improvement of Swank noise factor with increasing thickness is weak, and this energy-absorption noise characteristic dominates the DQE performance. The energy-absorption noise mainly limits the signal-to-noise performance of CdWO4 detectors operated at megavoltage x-ray beam.

  12. Pixel detector insertion

    CERN Multimedia

    CMS

    2015-01-01

    Insertion of the Pixel Tracker, the 66-million-channel device used to pinpoint the vertex of each colliding proton pair, located at the heart of the detector. The geometry of CMS is a cylinder lying on its side (22 meters long and 15 meters high in dia

  13. Sensitive hydrogen leak detector

    Science.gov (United States)

    Myneni, Ganapati Rao

    1999-01-01

    A sensitive hydrogen leak detector system using passivation of a stainless steel vacuum chamber for low hydrogen outgassing, a high compression ratio vacuum system, a getter operating at 77.5 K and a residual gas analyzer as a quantitative hydrogen sensor.

  14. B-factory detectors

    CERN Document Server

    Marlow, D R

    2002-01-01

    The designs of the recently commissioned BaBar and Belle B-Factory detectors are described. The discussion is organized around the methods and instruments used to detect the so-called gold-plated-mode B sup 0->J/PSI K sub S decays and related modes.

  15. The BABAR Detector

    CERN Document Server

    CERN. Geneva

    2002-01-01

    BABAR, the detector for the SLAC PEP-II asymmetric e+e- B Factory operating at the upsilon 4S resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

  16. CALIBRATION OF PHOSWICH DETECTORS

    NARCIS (Netherlands)

    LEEGTE, HKW; KOLDENHOF, EE; BOONSTRA, AL; WILSCHUT, HW

    1992-01-01

    Two important aspects for the calibration of phoswich detector arrays have been investigated. It is shown that common gate ADCs can be used: The loss in particle identification due to fluctuations in the gate timing in multi-hit events can be corrected for by a simple procedure using the measured ti

  17. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2012-01-01

    The RPC system is operating with a very high uptime, an average chamber efficiency of about 95% and an average cluster size around 1.8. The average number of active channels is 97.7%. Eight chambers are disconnected and forty are working in single-gap mode due to high-voltage problems. The total luminosity lost due to RPCs in 2012 is 88.46 pb–1. One of the main goals of 2012 was to improve the stability of the endcap trigger that is strongly correlated to the performances of the detector, due to the 3-out-3 trigger logic. At beginning of 2011 the instability of the detector efficiency was about 10%. Detailed studies found that this was mainly due to the strong correlation between the performance of the detector and the atmospheric pressure (P). Figure XXY shows the linear correlation between the average cluster size of the endcap chamber versus P. This effect is expected for gaseous detectors and can be reduced by correcting the applied high-voltage working point (HVapp) according to the followi...

  18. Ionic smoke detectors

    CERN Document Server

    2002-01-01

    Ionic smoke detectors are products incorporating radioactive material. This article summarises the process for their commercialization and marketing, and how the activity is controlled, according to regulations establishing strict design and production requisites to guarantee the absence of radiological risk associated both with their use and their final handling as conventional waste. (Author)

  19. ALICE Silicon Pixel Detector

    CERN Multimedia

    Manzari, V

    2013-01-01

    The Silicon Pixel Detector (SPD) forms the innermost two layers of the 6-layer barrel Inner Tracking System (ITS). The SPD plays a key role in the determination of the position of the primary collision and in the reconstruction of the secondary vertices from particle decays.

  20. The CLIC Vertex Detector

    CERN Document Server

    Dannheim, D

    2015-01-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a meas- urement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → W b will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit tim- ing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC ver- tex det...

  1. First ALICE detectors installed!

    CERN Multimedia

    2006-01-01

    Detectors to track down penetrating muon particles are the first to be placed in their final position in the ALICE cavern. The Alice muon spectrometer: in the foreground the trigger chamber is positioned in front of the muon wall, with the dipole magnet in the background. After the impressive transport of its dipole magnet, ALICE has begun to fill the spectrometer with detectors. In mid-July, the ALICE muon spectrometer team achieved important milestones with the installation of the trigger and the tracking chambers of the muon spectrometer. They are the first detectors to be installed in their final position in the cavern. All of the eight half planes of the RPCs (resistive plate chambers) have been installed in their final position behind the muon filter. The role of the trigger detector is to select events containing a muon pair coming, for instance, from the decay of J/ or Y resonances. The selection is made on the transverse momentum of the two individual muons. The internal parts of the RPCs, made o...

  2. Superconducting Single Photon Detectors

    NARCIS (Netherlands)

    Dorenbos, S.N.

    2011-01-01

    This thesis is about the development of a detector for single photons, particles of light. New techniques are being developed that require high performance single photon detection, such as quantum cryptography, single molecule detection, optical radar, ballistic imaging, circuit testing and fluoresc

  3. The BABAR Detector

    Energy Technology Data Exchange (ETDEWEB)

    Luth, Vera G

    2001-05-18

    BABAR, the detector for the SLAC PEP-II asymmetric e{sup +}e{sup -} B Factory operating at the {Upsilon}(4S) resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

  4. High-resolution ionization detector and array of such detectors

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S. (Ypsilanti, MI); Rojeski, Ronald A. (Pleasanton, CA)

    2001-01-16

    A high-resolution ionization detector and an array of such detectors are described which utilize a reference pattern of conductive or semiconductive material to form interaction, pervious and measurement regions in an ionization substrate of, for example, CdZnTe material. The ionization detector is a room temperature semiconductor radiation detector. Various geometries of such a detector and an array of such detectors produce room temperature operated gamma ray spectrometers with relatively high resolution. For example, a 1 cm.sup.3 detector is capable of measuring .sup.137 Cs 662 keV gamma rays with room temperature energy resolution approaching 2% at FWHM. Two major types of such detectors include a parallel strip semiconductor Frisch grid detector and the geometrically weighted trapezoid prism semiconductor Frisch grid detector. The geometrically weighted detector records room temperature (24.degree. C.) energy resolutions of 2.68% FWHM for .sup.137 Cs 662 keV gamma rays and 2.45% FWHM for .sup.60 Co 1.332 MeV gamma rays. The detectors perform well without any electronic pulse rejection, correction or compensation techniques. The devices operate at room temperature with simple commercially available NIM bin electronics and do not require special preamplifiers or cooling stages for good spectroscopic results.

  5. Fire Emulator/Detector Evaluator

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The fire emulator/detector evaluator (FE/DE) is a computer-controlled flow tunnel used to re-create the environments surrounding detectors in the early...

  6. Fire Emulator/Detector Evaluator

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The fire emulator/detector evaluator (FE/DE) is a computer-controlled flow tunnel used to re-create the environments surrounding detectors in the early...

  7. Position sensitive solid state detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schnatterly, S.E.; Husk, D.

    1986-05-15

    Solid state detectors have been used for years as high quantum efficiency detectors for visible light. In this paper the use of PDA and CCD, solid state detectors, in the X-ray region will be discussed. In particular examples of data in the soft X-ray region are presented. Finally the use of phosphor coatings to enhance the sensitivity of solid state detectors is described.

  8. Radiation detectors laboratory; Laboratorio de detectores de radiacion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez J, F.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  9. ATLAS Detector : Performance and Upgrades

    CERN Document Server

    Oliveira Damazio, Denis; The ATLAS collaboration

    2016-01-01

    Describe the ATLAS detector and summarize most relevant and recent information about the detector performance in 2016 with LHC colliding bunches at sqrt(s)=13 TeV with luminosity above the nominal value. Describe the different upgrade phases previewed for the detector and main activities already ongoing.

  10. Characterizations of GEM detector prototype

    CERN Document Server

    INSPIRE-00522505; Rudra, Sharmili; Bhattacharya, P.; Sahoo, Sumanya Sekhar; Biswas, S.; Mohanty, B.; Nayak, T.K.; Sahu, P.K.; Sahu, S.

    2016-01-01

    At NISER-IoP detector laboratory an initiative is taken to build and test Gas Electron Multiplier (GEM) detectors for ALICE experiment. The optimisation of the gas flow rate and the long-term stability test of the GEM detector are performed. The method and test results are presented.

  11. Characterisations of GEM detector prototype

    Energy Technology Data Exchange (ETDEWEB)

    Patra, Rajendra Nath [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, West Bengal (India); Nanda, Amit [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Rudra, Sharmili [Department of Applied Physics, CU, 92, APC Road, Kolkata 700009, West Bengal (India); Bhattacharya, P.; Sahoo, Sumanya Sekhar [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Biswas, S., E-mail: saikat.ino@gmail.com [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Mohanty, B. [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Nayak, T.K. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, West Bengal (India); Sahu, P.K.; Sahu, S. [Institute of Physics, Sachivalaya Marg, P.O.: Sainik School, Bhubaneswar 751005, Odisha (India)

    2016-07-11

    At NISER-IoP detector laboratory an initiative is taken to build and test Gas Electron Multiplier (GEM) detectors for ALICE experiment. The optimisation of the gas flow rate and the long-term stability test of the GEM detector are performed. The method and test results are presented.

  12. Workshops on radiation imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sochinskii, N.V.; Sun, G.C.; Kostamo, P.; Silenas, A.; Saynatjoki, A.; Grant, J.; Owens, A.; Kozorezov, A.G.; Noschis, E.; Van Eijk, C.; Nagarkar, V.; Sekiya, H.; Pribat, D.; Campbell, M.; Lundgren, J.; Arques, M.; Gabrielli, A.; Padmore, H.; Maiorino, M.; Volpert, M.; Lebrun, F.; Van der Putten, S.; Pickford, A.; Barnsley, R.; Anton, M.E.G.; Mitschke, M.; Gros d' Aillon, E.; Frojdh, C.; Norlin, B.; Marchal, J.; Quattrocchi, M.; Stohr, U.; Bethke, K.; Bronnimann, C.H.; Pouvesle, J.M.; Hoheisel, M.; Clemens, J.C.; Gallin-Martel, M.L.; Bergamaschi, A.; Redondo-Fernandez, I.; Gal, O.; Kwiatowski, K.; Montesi, M.C.; Smith, K

    2005-07-01

    This document gathers the transparencies that were presented at the international workshop on radiation imaging detectors. 9 sessions were organized: 1) materials for detectors and detector structure, 2) front end electronics, 3) interconnected technologies, 4) space, fusion applications, 5) the physics of detection, 6) industrial applications, 7) synchrotron radiation, 8) X-ray sources, and 9) medical and other applications.

  13. Detector and System Developments for LHC Detector Upgrades

    CERN Document Server

    Mandelli, Beatrice; Guida, Roberto; Rohne, Ole; Stapnes, Steinar

    2015-05-12

    The future Large Hadron Collider (LHC) Physics program and the consequent improvement of the LHC accelerator performance set important challenges to all detector systems. This PhD thesis delineates the studies and strategies adopted to improve two different types of detectors: the replacement of precision trackers with ever increasingly performing silicon detectors, and the improvement of large gaseous detector systems by optimizing their gas mixtures and operation modes. Within the LHC tracker upgrade programs, the ATLAS Insertable B-layer (IBL) is the first major upgrade of a silicon-pixel detector. Indeed the overall ATLAS Pixel Detector performance is expected to degrade with the increase of luminosity and the IBL will recover the performance by adding a fourth innermost layer. The IBL Detector makes use of new pixel and front-end electronics technologies as well as a novel thermal management approach and light support and service structures. These innovations required complex developments and Quality Ass...

  14. Acoustic absorption by sunspots

    Science.gov (United States)

    Braun, D. C.; Labonte, B. J.; Duvall, T. L., Jr.

    1987-01-01

    The paper presents the initial results of a series of observations designed to probe the nature of sunspots by detecting their influence on high-degree p-mode oscillations in the surrounding photosphere. The analysis decomposes the observed oscillations into radially propagating waves described by Hankel functions in a cylindrical coordinate system centered on the sunspot. From measurements of the differences in power between waves traveling outward and inward, it is demonstrated that sunspots appear to absorb as much as 50 percent of the incoming acoustic waves. It is found that for all three sunspots observed, the amount of absorption increases linearly with horizontal wavenumber. The effect is present in p-mode oscillations with wavelengths both significantly larger and smaller than the diameter of the sunspot umbrae. Actual absorption of acoustic energy of the magnitude observed may produce measurable decreases in the power and lifetimes of high-degree p-mode oscillations during periods of high solar activity.

  15. Chaotic systems with absorption

    CERN Document Server

    Altmann, Eduardo G; Tél, Tamás

    2013-01-01

    Motivated by applications in optics and acoustics we develop a dynamical-system approach to describe absorption in chaotic systems. We introduce an operator formalism from which we obtain (i) a general formula for the escape rate $\\kappa$ in terms of the natural conditionally-invariant measure of the system; (ii) an increased multifractality when compared to the spectrum of dimensions $D_q$ obtained without taking absorption and return times into account; and (iii) a generalization of the Kantz-Grassberger formula that expresses $D_1$ in terms of $\\kappa$, the positive Lyapunov exponent, the average return time, and a new quantity, the reflection rate. Simulations in the cardioid billiard confirm these results.

  16. Photoinduced absorption of polyalkylthienylenevinylenes

    Energy Technology Data Exchange (ETDEWEB)

    Botta, C. (Ist. di Chimica delle Macromolecole (CNR), Milano (Italy)); Bradley, D.D.C. (Cambridge Univ. (United Kingdom). Cavendish Lab.); Friend, R.H. (Cambridge Univ. (United Kingdom). Cavendish Lab.); Musco, A. (Ist. di Scienze Chimiche, Univ. di Urbino (Italy))

    1993-03-15

    We present a photoinduced absorption study of alkyl substituted poly(2,5-thienylenevinylene)s. Three photoinduced states are detected in both the solid state and in solution. The two low-energy bands are assigned to bipolarons, while a third band peaked near the band edge has a different origin. In solution photoexcitated states are very long-lived and we propose that photoexcitation recombine via a solvent-assisted photo-doping mechanism. (orig.)

  17. Hydrogen Absorption by Niobium.

    Science.gov (United States)

    1982-04-13

    incorporate an independent means for ascertaining surface cleanliness (e.g. AES). The form of the absorption curve in Fig. 7 appears to agree with that...very interesting study and is well within the capabilities of the systen designed, if the surface cleanliness can be assured. Wire specimens have a...assessing surface cleanliness would be an important supporting technique for understanding the results of these measurements. The simple kinetic

  18. Future liquid Argon detectors

    CERN Document Server

    Rubbia, A

    2013-01-01

    The Liquid Argon Time Projection Chamber offers an innovative technology for a new class of massive detectors for rare-event detection. It is a precise tracking device that allows three-dimensional spatial reconstruction with mm-scale precision of the morphology of ionizing tracks with the imaging quality of a "bubble chamber", provides $dE/dx$ information with high sampling rate, and acts as high-resolution calorimeter for contained events. First proposed in 1977 and after a long maturing process, its holds today the potentialities of opening new physics opportunities by providing excellent tracking and calorimetry performance at the relevant multi-kton mass scales, outperforming other techniques. In this paper, we review future liquid argon detectors presently being discussed by the neutrino physics community.

  19. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  20. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    Since September, the muon alignment system shifted from a mode of hardware installation and commissioning to operation and data taking. All three optical subsystems (Barrel, Endcap and Link alignment) have recorded data before, during and after CRAFT, at different magnetic fields and during ramps of the magnet. This first data taking experience has several interesting goals: •    study detector deformations and movements under the influence of the huge magnetic forces; •    study the stability of detector structures and of the alignment system over long periods, •    study geometry reproducibility at equal fields (specially at 0T and 3.8T); •    reconstruct B=0T geometry and compare to nominal/survey geometries; •    reconstruct B=3.8T geometry and provide DT and CSC alignment records for CMSSW. However, the main goal is to recons...

  1. The LUCID detector

    CERN Document Server

    Lasagni Manghi, Federico; The ATLAS collaboration

    2015-01-01

    Starting from 2015 LHC is performing a new run, at higher center of mass energy (13 TeV) and with 25 ns bunch-spacing. The ATLAS luminosity monitor LUCID has been completely renewed, both on detector design and in the electronics, in order to cope with the new running conditions. The new detector electronics is presented, featuring a new read-out board (LUCROD), for signal acquisition and digitization, PMT-charge integration and single-side luminosity measurements, and the revisited LUMAT board for side-A-side-C combination. The contribution covers the new boards design, the firmware and software developments, the implementation of luminosity algorithms, the optical communication between boards and the integration into the ATLAS TDAQ system.

  2. UA1 central detector

    CERN Multimedia

    The UA1 central detector was crucial to understanding the complex topology of proton-antiproton events. It played a most important role in identifying a handful of Ws and Zs among billions of collisions. The detector was a 6-chamber cylindrical assembly 5.8 m long and 2.3 m in diameter, the largest imaging drift chamber of its day. It recorded the tracks of charged particles curving in a 0.7 Tesla magnetic field, measuring their momentum, the sign of their electric charge and their rate of energy loss (dE/dx). Atoms in the argon-ethane gas mixture filling the chambers were ionised by the passage of charged particles. The electrons which were released drifted along an electric field shaped by field wires and were collected on sense wires. The geometrical arrangement of the 17000 field wires and 6125 sense wires allowed a spectacular 3-D interactive display of reconstructed physics events to be produced.

  3. Metrology with Unknown Detectors.

    Science.gov (United States)

    Altorio, Matteo; Genoni, Marco G; Somma, Fabrizia; Barbieri, Marco

    2016-03-11

    The best possible precision is one of the key figures in metrology, but this is established by the exact response of the detection apparatus, which is often unknown. There exist techniques for detector characterization that have been introduced in the context of quantum technologies but apply as well for ordinary classical coherence; these techniques, though, rely on intense data processing. Here, we show that one can make use of the simpler approach of data fitting patterns in order to obtain an estimate of the Cramér-Rao bound allowed by an unknown detector, and we present applications in polarimetry. Further, we show how this formalism provides a useful calculation tool in an estimation problem involving a continuous-variable quantum state, i.e., a quantum harmonic oscillator.

  4. Aerogel for FARICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Barnyakov, A.Yu. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Barnyakov, M.Yu. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, Karl Marks 20, Novosibirsk 630073 (Russian Federation); Bobrovnikov, V.S.; Buzykaev, A.R.; Gulevich, V.V. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Danilyuk, A.F. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation); Kononov, S.A.; Kravchenko, E.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova 2, Novosibirsk 630090 (Russian Federation); Kuyanov, I.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Lopatin, S.A. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation); Onuchin, A.P.; Ovtin, I.V.; Podgornov, N.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, Karl Marks 20, Novosibirsk 630073 (Russian Federation); Porosev, V.V. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Predein, A.Yu.; Protsenko, R.S. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation)

    2014-12-01

    We present our current experience in preparation of focusing aerogels for the Focusing Aerogel RICH detector. Multilayer focusing aerogel tiles have been produced in Novosibirsk by a collaboration of the Budker Institute of Nuclear Physics and Boreskov Institute of Catalysis since 2004. We have obtained 2–3–4-layer blocks with the thickness of 30–45 mm. In 2012, the first samples of focusing blocks with continuous density (refractive index) gradient along thickness were produced. This technology can significantly reduce the contribution from the geometric factor of the radiator thickness to the resolution of the measured Cherenkov angle in the FARICH detector. The special installation was used for automatic control of reagents ratio during the synthesis process. The first samples were tested using the digital radiography method and on the electron beam with the FARICH prototype.

  5. Metrology with Unknown Detectors

    CERN Document Server

    Altorio, Matteo; Somma, Fabrizia; Barbieri, Marco

    2015-01-01

    The best possible precision is one of the key figures in metrology, but this is established by the exact response of the detection apparatus, which is often unknown. There exist techniques for detector characterisation, that have been introduced in the context of quantum technologies, but apply as well for ordinary classical coherence; these techniques, though, rely on intense data processing. Here we show that one can make use of the simpler approach of data fitting patterns in order to obtain an estimate of the Cram\\'er-Rao bound allowed by an unknown detector, and present applications in polarimetry. Further, we show how this formalism provide a useful calculation tool in an estimation problem involving a continuous-variable quantum state, i.e. a quantum harmonic oscillator.

  6. Radiation damage in silicon detectors

    CERN Document Server

    Lindström, G

    2003-01-01

    Radiation damage effects in silicon detectors under severe hadron and gamma-irradiation are surveyed, focusing on bulk effects. Both macroscopic detector properties (reverse current, depletion voltage and charge collection) as also the underlying microscopic defect generation are covered. Basic results are taken from the work done in the CERN-RD48 (ROSE) collaboration updated by results of recent work. Preliminary studies on the use of dimerized float zone and Czochralski silicon as detector material show possible benefits. An essential progress in the understanding of the radiation-induced detector deterioration had recently been achieved in gamma irradiation, directly correlating defect analysis data with the macroscopic detector performance.

  7. Detectors for the space telescope

    Science.gov (United States)

    Kelsall, T.

    1978-01-01

    This review of Space Telescope (ST) detectors is divided into two parts. The first part gives short summaries of detector programs carried out during the final planning stage (Phase B) of the ST and discusses such detectors as Photicon, the MAMA detectors, the CODACON, the University of Maryland ICCD, the Goddard Space Flight Center ICCD, and the 70 mm SEC TV sensor. The second part describes the detectors selected for the first ST flight, including the wide field/planetary camera, the faint object and high resolution spectrographs, and the high speed photometer.

  8. Biological detector and method

    Energy Technology Data Exchange (ETDEWEB)

    Sillerud, Laurel; Alam, Todd M.; McDowell, Andrew F.

    2015-11-24

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  9. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2014-04-15

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  10. The AMANDA Neutrino Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wischnewski, R.; Andres, E.; Askebjer, P.; Barwick, S.; Bay, R.; Bergstrom, L.; Biron, A.; Booth, J.; Botner, O.; Bouchta, A.; Carius, S.; Carlson, M.; Chinowsky, W.; Chirkin, D.; Cowen, D.; Costa, C.; Dalberg,E.; Deyoung, T.; Edsjo, J.; Ekstrom, P.; Goobar, A.; Gray, L.; Hallgren,A.; Halzen, F.; Hardtke, R.; He, Y.; Hill, G.; Hulth, P.; Hundertmark,S.; Jacobsen, J.; Kandhadai, V.; Karle, A.; Kim, J.; Leich, H.; Leuthold,M.; Lindahl, P.; Liss, T.; Liubarsky, I.; Loaiza, P.; Lowder, D.; Marciniewski, P.; Miller, T.; Miocinovic, P.; Mock, P.; Morse, R.; Newcomer, M.; Niessen, P.; Nygren, D.; de, los, Heros, CP.; Porrata, R.; Price, P.; Przybylski, G.; Rhode, W.; Richter, S.; Rodriguez, J.; Romenesko, P.; Ross, D.; Rubinstein, H.; Schmidt, T.; Schneider, E.; Schwarz, R.; Schwendicke, U.; Smoot, G.; Solarz, M.; Sorin, V.; Spiering,C.; Steffen, P.; Stokstad, R.; Streicher, O.; Thollander, L.; Thon, T.; Tilav, S.; Walck, C.; Wiebusch, C.; Woschnagg, K.; Wu, W.; Yodh, G.; Young, S.

    1999-08-23

    The first stage of the AMANDA High Energy Neutrino Detectorat the South Pole, the 302 PMT array AMANDA-B with an expected effectivearea for TeV neutrinos of similar to 10(4) m(2), has been taking datasince 1997. Progress with calibration, investigation of ice properties,as well as muon and neutrino data analysis are described. The next stage20-string detector AMANDA-II with similar to 800 PMTs will be completedin spring 2000.

  11. The ALEPH detector

    CERN Document Server

    1988-01-01

    For detecting the direction and momenta of charged particles with extreme accuracy, the ALEPH detector had at its core a time projection chamber, for years the world's largest. In the foreground from the left, Jacques Lefrancois, Jack Steinberger, Lorenzo Foa and Pierre Lazeyras. ALEPH was an experiment on the LEP accelerator, which studied high-energy collisions between electrons and positrons from 1989 to 2000.

  12. LHCb velo detector

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    Photo 01 : L. to r.: D. Malinon, Summer Student, J. Libby, Fellow, J. Harvey, Head of CERN LHCb group, D. Schlatter, Head of the EP Division in front of the LHCb velo detector test beam (on the right). Photo 02 : L. to r.: J. Harvey, D. Schlatter, W. Riegler (staff), H.J. Hilke, LHCb Technical Coordinator in front of the muon chamber test beam

  13. Development of Portable Detectors

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-12-01

    The purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC (the “Contractor”) and Sense Holdings, Inc. (the “Participant”) was for the development of hand-held detectors with high sensitivity and selectivity for the detection of explosives, toxic industrial chemicals and materials, and other materials of interest for security applications. The two parties built a series of demonstration and prototype handheld sensors based upon micoelectromechanical systems (MEMS) with electronic readout.

  14. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2013-02-26

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  15. Evaluation of dome-input geometry for pyroelectric detectors

    Science.gov (United States)

    Zeng, J.; Hanssen, L. M.; Eppeldauer, G. P.

    2013-06-01

    Dome-input pyroelectric radiometers with different black coatings were developed to extend the spectral responsivity scale from near infrared (NIR) to 20 μm. The reflective dome with shiny gold-coating has been known to be an efficient light trap to enhance the detector absorptance and to minimize spectral responsivity variation. The enhancement of spectral responsivity using reflective dome relies on optical characterization of black coating on detector, reflectance of dome reflector, and input aperture dimension, etc. We report a comparison of spectral responsivity of dome-input pyroelectric radiometers measured with/without dome-trap from 2.4 μm to 14 μm using the Infrared Spectral Comparator Facility (IRSCF) at NIST. The results show 4 % to 8 % gain of responsivity for two dome-input pyroelectric detectors, with reduced structure of spectral responsivity. The uncertainty of dome-input pyroelectric radiometer calibrations is approximately 2 % (k = 2).

  16. Corrosion Problems in Absorption Chillers

    Science.gov (United States)

    Stetson, Bruce

    1978-01-01

    Absorption chillers use a lithium bromide solution as the medium of absorption and water as the refrigerant. Discussed are corrosion and related problems, tests and remedies, and cleaning procedures. (Author/MLF)

  17. Virtual edge illumination and one dimensional beam tracking for absorption, refraction, and scattering retrieval

    Energy Technology Data Exchange (ETDEWEB)

    Vittoria, Fabio A., E-mail: fabio.vittoria.12@ucl.ac.uk; Diemoz, Paul C. [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom); Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot (United Kingdom); Endrizzi, Marco; Olivo, Alessandro [Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower Street, London WC1E 6BT (United Kingdom); Wagner, Ulrich H.; Rau, Christoph [Diamond Light Source, Harwell Oxford Campus, OX11 0DE Didcot (United Kingdom); Robinson, Ian K. [Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot (United Kingdom); London Centre for Nanotechnology, WC1H 0AH London (United Kingdom)

    2014-03-31

    We propose two different approaches to retrieve x-ray absorption, refraction, and scattering signals using a one dimensional scan and a high resolution detector. The first method can be easily implemented in existing procedures developed for edge illumination to retrieve absorption and refraction signals, giving comparable image quality while reducing exposure time and delivered dose. The second method tracks the variations of the beam intensity profile on the detector through a multi-Gaussian interpolation, allowing the additional retrieval of the scattering signal.

  18. Hybrid superconducting neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Merlo, V.; Lucci, M.; Ottaviani, I. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); Salvato, M.; Cirillo, M. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); CNR SPIN Salerno, Università di Salerno, Via Giovanni Paolo II, n.132, 84084 Fisciano (Italy); Scherillo, A. [Science and Technology Facility Council, ISIS Facility Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Celentano, G. [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Pietropaolo, A., E-mail: antonino.pietropaolo@enea.it [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Mediterranean Institute of Fundamental Physics, Via Appia Nuova 31, 00040 Marino, Roma (Italy)

    2015-03-16

    A neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction, {sup 10}B + n → α + {sup 7}Li, with α and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current I{sub c}, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the basic physical features of the detector are discussed.

  19. MUON DETECTORS: DT

    CERN Multimedia

    M. Dallavalle.

    The DT system is ready for the LHC start up. The status of detector hardware, control and safety, of the software for calibration and monitoring and of people has been reviewed at several meetings, starting with the CMS Action Matrix Review and with the Muon Barrel Workshop (October 5 to 7). The disconnected HV channels are at a level of about 0.1%. The loss in detector acceptance because of failures in the Read-Out and Trigger electronics is about 0.5%. The electronics failure rate has been lower this year: next year will tell us whether the rate has stabilised and hopefully will confirm that the number of spares is adequate for ten years operation. Although the detector safety control is very accurate and robust, incidents have happened. In particular the DT system suffered from a significant water leak, originated in the top part of YE+1, that generated HV trips in eighteen chambers going transversely down from the top sector in YB+2 to the bottom sector in YB-2. All chambers recovered and all t...

  20. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2011-01-01

    During data-taking in 2010 the RPC system behaviour was very satisfactory for both the detector and trigger performances. Most of the data analyses are now completed and many results and plots have been approved in order to be published in the muon detector paper. A very detailed analysis of the detector efficiency has been performed using 60 million muon events taken with the dedicated RPC monitor stream. The results have shown that the 96.3% of the system was working properly with an average efficiency of 95.4% at 9.35 kV in the Barrel region and 94.9% at 9.55 kV in the Endcap. Cluster size goes from 1.6 to 2.2 showing a clear and well-known correlation with the strip pitch. Average noise in the Barrel is less than 0.4 Hz/cm2 and about 98% of full system has averaged noise less then 1 Hz/cm2. A linear dependence of the noise versus the luminosity has been preliminary observed and is now under study. Detailed chamber efficiency maps have shown a few percent of chambers with a non-uniform efficiency distribu...

  1. UA1 prototype detector

    CERN Multimedia

    1980-01-01

    Prototype of UA1 central detector inside a plexi tube. The UA1 central detector was crucial to understanding the complex topology of proton-antiproton events. It played a most important role in identifying a handful of Ws and Zs among billions of collisions. The detector was a 6-chamber cylindrical assembly 5.8 m long and 2.3 m in diameter, the largest imaging drift chamber of its day. It recorded the tracks of charged particles curving in a 0.7 Tesla magnetic field, measuring their momentum, the sign of their electric charge and their rate of energy loss (dE/dx). Atoms in the argon-ethane gas mixture filling the chambers were ionised by the passage of charged particles. The electrons which were released drifted along an electric field shaped by field wires and were collected on sense wires. The geometrical arrangement of the 17000 field wires and 6125 sense wires allowed a spectacular 3-D interactive display of reconstructed physics events to be produced.

  2. The STAR PXL detector

    Science.gov (United States)

    Contin, G.

    2016-12-01

    The PiXeL detector (PXL) of the STAR experiment at RHIC is the first application of the state-of-the-art thin Monolithic Active Pixel Sensors (MAPS) technology in a collider environment. Designed to extend the STAR measurement capabilities in the heavy flavor domain, it took data in Au+Au collisions, p+p and p+Au collisions at 0√sNN=20 GeV at RHIC, during the period 2014-2016. The PXL detector is based on 50 μm-thin MAPS sensors with a pitch of 20.7 μm. Each sensor includes an array of nearly 1 million pixels, read out in rolling shutter mode in 185.6 μs. The 170 mW/cm2 power dissipation allows for air cooling and contributes to reduce the global material budget to 0.4% radiation length on the innermost layer. Experience and lessons learned from construction and operations will be presented in this paper. Detector performance and results from 2014 Au+Au data analysis, demonstrating the STAR capabilities of charm reconstruction, will be shown.

  3. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2011-01-01

    RPC detector calibration, HV scan Thanks to the high LHC luminosity and to the corresponding high number of muons created in the first part of the 2011 the RPC community had, for the first time, the possibility to calibrate every single detector element (roll).The RPC steering committee provided the guidelines for both data-taking and data analysis and a dedicated task force worked from March to April on this specific issue. The main goal of the RPC calibration was to study the detector efficiency as a function of high-voltage working points, fit the obtained “plateau curve” with a sigmoid function and determine the “best” high-voltage working point of every single roll. On 18th and 19th March, we had eight runs at different voltages. On 27th March, the full analysis was completed, showing that 60% of the rolls had already a very good fit with an average efficiency greater than 93% in the plateau region. To improve the fit we decided to take three more runs (15th April...

  4. Commissioning the SNO+ detector

    Science.gov (United States)

    Descamps, Freija; SNO+ Collaboration

    2016-09-01

    The SNO+ experiment is the successor to the Sudbury Neutrino Observatory (SNO), in which SNO's heavy water is replaced by approximately 780T of liquid scintillator (LAB). The combination of the 2km underground location, the use of ultra-clean materials and the high light-yield of the liquid scintillator means that a low background level and a low energy threshold can be achieved. This creates a new multipurpose neutrino detector with the potential to address a diverse set of physics goals, including the detection of reactor, solar, geo- and supernova neutrinos. A main physics goal of SNO+ is the search for neutrinoless double beta decay. By loading the liquid scintillator with 0.5% of natural Tellurium, resulting in about 1300kg of 130Te (isotopic abundance is slightly over 34%), a competitive sensitivity to the effective neutrino mass can be reached. This talk will present the status of the SNO+ detector, specifically the results and status of the detector commissioning with water.

  5. The STAR Vertex Position Detector

    CERN Document Server

    Llope, W J; Nussbaum, T; Hoffmann, G W; Asselta, K; Brandenburg, J D; Butterworth, J; Camarda, T; Christie, W; Crawford, H J; Dong, X; Engelage, J; Eppley, G; Geurts, F; Hammond, J; Judd, E; McDonald, D L; Perkins, C; Ruan, L; Scheblein, J; Schambach, J J; Soja, R; Xin, K; Yang, C

    2014-01-01

    The 2x3 channel pseudo Vertex Position Detector (pVPD) in the STAR experiment at RHIC has been upgraded to a 2x19 channel detector in the same acceptance, called the Vertex Position Detector (VPD). This detector is fully integrated into the STAR trigger system and provides the primary input to the minimum-bias trigger in Au+Au collisions. The information from the detector is used both in the STAR Level-0 trigger and offline to measure the location of the primary collision vertex along the beam pipe and the event "start time" needed by other fast-timing detectors in STAR. The offline timing resolution of single detector channels in full-energy Au+Au collisions is ~100 ps, resulting in a start time resolution of a few tens of picoseconds and a resolution on the primary vertex location of ~1 cm.

  6. Development and performance of a gamma-ray imaging detector

    Science.gov (United States)

    Gálvez, J. L.; Hernanz, M.; Álvarez, J. M.; La Torre, M.; Álvarez, L.; Karelin, D.; Lozano, M.; Pellegrini, G.; Ullán, M.; Cabruja, E.; Martínez, R.; Chmeissani, M.; Puigdengoles, C.

    2012-09-01

    In the last few years we have been working on feasibility studies of future instruments in the gamma-ray range, from several keV up to a few MeV. The innovative concept of focusing gamma-ray telescopes in this energy range, should allow reaching unprecedented sensitivities and angular resolution, thanks to the decoupling of collecting area and detector volume. High sensitivities are essential to perform detailed studies of cosmic explosions and cosmic accelerators, e.g., Supernovae, Classical Novae, Supernova Remnants (SNRs), Gamma-Ray Bursts (GRBs), Pulsars, Active Galactic Nuclei (AGN). In order to achieve the needed performance, a gamma-ray imaging detector with mm spatial resolution and large enough efficiency is required. In order to fulfill the combined requirement of high detection efficiency with good spatial and energy resolution, an initial prototype of a gamma-ray imaging detector based on CdTe pixel detectors is being developed. It consists of a stack of several layers of CdTe detectors with increasing thickness, in order to enhance the gamma-ray absorption in the Compton regime. A CdTe module detector lies in a 11 x 11 pixel detector with a pixel pitch of 1mm attached to the readout chip. Each pixel is bump bonded to a fan-out board made of alumina (Al2O3) substrate and routed to the corresponding input channel of the readout ASIC to measure pixel position and pulse height for each incident gamma-ray photon. We will report the main features of the gamma-ray imaging detector performance such as the energy resolution for a set of radiation sources at different operating temperatures.

  7. Converting Sabine absorption coefficients to random incidence absorption coefficients

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2013-01-01

    Absorption coefficients measured by the chamber method are referred to as Sabine absorption coefficients, which sometimes exceed unity due to the finite size of a sample and non-uniform intensity in the reverberation chambers under test. In this study, conversion methods from Sabine absorption...... coefficients to random incidence absorption coefficients are proposed. The overestimations of the Sabine absorption coefficient are investigated theoretically based on Miki's model for porous absorbers backed by a rigid wall or an air cavity, resulting in conversion factors. Additionally, three optimizations...

  8. Dawn Grand Map Vesta Neutron Absorption V1.0

    Science.gov (United States)

    Prettyman, T. H.

    2014-06-01

    A global map of a unitless compositional parameter, delta-C_perpendicular (DCP), and propagated 1-sigma uncertainties is provided. DCP varies linearly with the macroscopic thermal neutron absorption cross section of Vesta's regolith. An equation for converting tabulated DCP values to absorption units is provided in this document. DCP was determined from thermal and epithermal neutron counting rates measured by the NASA Dawn mission's Gamma Ray and Neutron Detector (GRaND) while in low altitude mapping orbit, about 210 km from Vesta's surface. The measurements are representative of Vesta's bulk regolith composition to depths of a few decimeters with a spatial resolution of about 300-km full-width-at-half-maximum of arc length on the surface. The methods used to determine neutron absorption are described by PRETTYMANETAL2013.

  9. Femtosecond laser irradiation-induced infrared absorption on silicon surfaces

    Directory of Open Access Journals (Sweden)

    Qinghua Zhu

    2015-04-01

    Full Text Available The near-infrared (NIR absorption below band gap energy of crystalline silicon is significantly increased after the silicon is irradiated with femtosecond laser pulses at a simple experimental condition. The absorption increase in the NIR range primarily depends on the femtosecond laser pulse energy, pulse number, and pulse duration. The Raman spectroscopy analysis shows that after the laser irradiation, the silicon surface consists of silicon nanostructure and amorphous silicon. The femtosecond laser irradiation leads to the formation of a composite of nanocrystalline, amorphous, and the crystal silicon substrate surface with microstructures. The composite has an optical absorption enhancement at visible wavelengths as well as at NIR wavelength. The composite may be useful for an NIR detector, for example, for gas sensing because of its large surface area.

  10. Method and apparatus for background signal reduction in opto-acoustic absorption measurement

    Science.gov (United States)

    Rosengren, L. G. (Inventor)

    1976-01-01

    The sensitivity of an opto-acoustic absorption detector is increased to make it possible to measure trace amounts of constituent gases. A second beam radiation path is created through the sample cell identical to a first path except as to length, alternating the beam through the two paths and minimizing the detected pressure difference for the two paths while the beam wavelength is tuned away from the absorption lines of the sample. Then with the beam wavelength tuned to the absorption line of any constituent of interest, the pressure difference is a measure of trace amounts of the constituent. The same improved detector may also be used for measuring the absorption coefficient of known concentrations of absorbing gases.

  11. Acoustic Absorption Characteristics of People.

    Science.gov (United States)

    Kingsbury, H. F.; Wallace, W. J.

    1968-01-01

    The acoustic absorption characteristics of informally dressed college students in typical classroom seating are shown to differ substantially from data for formally dressed audiences in upholstered seating. Absorption data, expressed as sabins per person or absorption coefficient per square foot, shows that there is considerable variation between…

  12. Low-energy neutron flux measurement using a resonance absorption filter surrounding a lithium glass scintillator

    Science.gov (United States)

    Ghal-Eh, N.; Koohi-Fayegh, R.; Hamidi, S.

    2007-06-01

    The resonance absorption filter technique has been used to determine the thermal/epithermal neutron flux. The main idea in this technique is to use an element with a high and essentially singular resonance in the neutron absorption cross section as a filter surrounding a miniature-type lithium glass scintillator. The count with and without the filter surrounding the detector gives the number of resonance-energy neutrons. Some preliminary results and a comparison with the MCNP code are shown.

  13. Quantum dot resonant tunneling diode single photon detector with aluminum oxide aperture defined tunneling area

    DEFF Research Database (Denmark)

    Li, H.W.; Kardynal, Beata; Ellis, D.J.P.

    2008-01-01

    Quantum dot resonant tunneling diode single photon detector with independently defined absorption and sensing areas is demonstrated. The device, in which the tunneling is constricted to an aperture in an insulating layer in the emitter, shows electrical characteristics typical of high quality...... resonant tunneling diodes. A single photon detection efficiency of 2.1%+/- 0.1% at 685 nm was measured corresponding to an internal quantum efficiency of 14%. The devices are simple to fabricate, robust, and show promise for large absorption area single photon detectors based on quantum dot structures....

  14. Absorption in dielectric models

    CERN Document Server

    Churchill, R J

    2015-01-01

    We develop a classical microscopic model of a dielectric. The model features nonlinear interaction terms between polarizable dipoles and lattice vibrations. The lattice vibrations are found to act as a pseudo-reservoir, giving broadband absorption of electromagnetic radiation without the addition of damping terms in the dynamics. The effective permittivity is calculated using a perturbative iteration method and is found to have the form associated with real dielectrics. Spatial dispersion is naturally included in the model and we also calculate the wavevector dependence of the permittivity.

  15. The DELPHI Detector (DEtector with Lepton Photon and Hadron Identification)

    CERN Multimedia

    Crawley, B; Munich, K; Mckay, R; Matorras, F; Joram, C; Malychev, V; Behrmann, A; Van dam, P; Drees, J K; Stocchi, A; Adam, W; Booth, P; Bilenki, M; Rosenberg, E I; Morton, G; Rames, J; Hahn, S; Cosme, G; Ventura, L; Marco, J; Tortosa martinez, P; Monge silvestri, R; Moreno, S; Phillips, H; Alekseev, G; Boudinov, E; Martinez rivero, C; Gitarskiy, L; Davenport, M; De clercq, C; Firestone, A; Myagkov, A; Belous, K; Haider, S; Hamilton, K M; Lamsa, J; Rahmani, M H; Malek, A; Hughes, G J; Peralta, L; Carroll, L; Fuster verdu, J A; Cossutti, F; Gorn, L; Yi, J I; Bertrand, D; Myatt, G; Richard, F; Shapkin, M; Hahn, F; Ferrer soria, A; Reinhardt, R; Renton, P; Sekulin, R; Timmermans, J; Baillon, P

    2002-01-01

    % DELPHI The DELPHI Detector (Detector with Lepton Photon and Hadron Identification) \\\\ \\\\DELPHI is a general purpose detector for physics at LEP on and above the Z$^0$, offering three-dimensional information on curvature and energy deposition with fine spatial granularity as well as identification of leptons and hadrons over most of the solid angle. A superconducting coil provides a 1.2~T solenoidal field of high uniformity. Tracking relies on the silicon vertex detector, the inner detector, the Time Projection Chamber (TPC), the outer detector and forward drift chambers. Electromagnetic showers are measured in the barrel with high granularity by the High Density Projection Chamber (HPC) and in the endcaps by $ 1 ^0 $~x~$ 1 ^0 $ projective towers composed of lead glass as active material and phototriode read-out. Hadron identification is provided mainly by liquid and gas Ring Imaging Counters (RICH). The instrumented magnet yoke serves for hadron calorimetry and as filter for muons, which are identified in t...

  16. Geospatial Absorption and Regional Effects

    Directory of Open Access Journals (Sweden)

    IOAN MAC

    2009-01-01

    Full Text Available The geospatial absorptions are characterized by a specific complexity both in content and in their phenomenological and spatial manifestation fields. Such processes are differentiated according to their specificity to pre-absorption, absorption or post-absorption. The mechanisms that contribute to absorption are extremely numerous: aggregation, extension, diffusion, substitution, resistivity (resilience, stratification, borrowings, etc. Between these mechanisms frequent relations are established determining an amplification of the process and of its regional effects. The installation of the geographic osmosis phenomenon in a given territory (a place for example leads to a homogenization of the geospatial state and to the installation of the regional homogeneity.

  17. Broadband illumination of superconducting pair breaking photon detectors

    Science.gov (United States)

    Guruswamy, T.; Goldie, D. J.; Withington, S.

    2016-04-01

    Understanding the detailed behaviour of superconducting pair breaking photon detectors such as Kinetic Inductance Detectors (KIDs) requires knowledge of the nonequilibrium quasiparticle energy distributions. We have previously calculated the steady state distributions resulting from uniform absorption of monochromatic sub gap and above gap frequency radiation by thin films. In this work, we use the same methods to calculate the effect of illumination by broadband sources, such as thermal radiation from astrophysical phenomena or from the readout system. Absorption of photons at multiple above gap frequencies is shown to leave unchanged the structure of the quasiparticle energy distribution close to the superconducting gap. Hence for typical absorbed powers, we find the effects of absorption of broadband pair breaking radiation can simply be considered as the sum of the effects of absorption of many monochromatic sources. Distribution averaged quantities, like quasiparticle generation efficiency η, match exactly a weighted average over the bandwidth of the source of calculations assuming a monochromatic source. For sub gap frequencies, however, distributing the absorbed power across multiple frequencies does change the low energy quasiparticle distribution. For moderate and high absorbed powers, this results in a significantly larger η-a higher number of excess quasiparticles for a broadband source compared to a monochromatic source of equal total absorbed power. Typically in KIDs the microwave power absorbed has a very narrow bandwidth, but in devices with broad resonance characteristics (low quality factors), this increase in η may be measurable.

  18. Absorption Spectra of Astaxanthin Aggregates

    CERN Document Server

    Olsina, Jan; Minofar, Babak; Polivka, Tomas; Mancal, Tomas

    2012-01-01

    Carotenoids in hydrated polar solvents form aggregates characterized by dramatic changes in their absorption spectra with respect to monomers. Here we analyze absorption spectra of aggregates of the carotenoid astaxanthin in hydrated dimethylsulfoxide. Depending on water content, two types of aggregates were produced: H-aggregates with absorption maximum around 390 nm, and J-aggregates with red-shifted absorption band peaking at wavelengths >550 nm. The large shifts with respect to absorption maximum of monomeric astaxanthin (470-495 nm depending on solvent) are caused by excitonic interaction between aggregated molecules. We applied molecular dynamics simulations to elucidate structure of astaxanthin dimer in water, and the resulting structure was used as a basis for calculations of absorption spectra. Absorption spectra of astaxanthin aggregates in hydrated dimethylsulfoxide were calculated using molecular exciton model with the resonance interaction energy between astaxanthin monomers constrained by semi-e...

  19. The HI absorption 'Zoo'

    CERN Document Server

    Gereb, K; Morganti, R; Oosterloo, T A

    2014-01-01

    We present an analysis of the HI absorption in a sample of 101 flux-selected radio AGN (S_1.4 GHz > 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). HI absorption is detected in 32 galaxies, showing a broad variety of widths, shapes and kinematical properties. We characterize the HI spectra of the individual detections using the busy function (Westmeier et al. 2014). With the goal of identifying different morphological structures of HI, we study the kinematical and radio source properties of the detections as function of their width. Narrow lines (FWHM = 500 km/s). These detections are good candidates for being HI outflows. The detection rate of HI outflows is 5 percent in the total radio AGN sample. This fraction represents a lower limit, however it could suggests that, if outflows are a characteristic phenomenon of all radio sources, they would have a short depletion timescale compared to the lifetime of the AGN. Blueshifted and broad/asymmetric lines are more often present among young...

  20. Optically thin hybrid cavity for terahertz photo-conductive detectors

    Science.gov (United States)

    Thompson, R. J.; Siday, T.; Glass, S.; Luk, T. S.; Reno, J. L.; Brener, I.; Mitrofanov, O.

    2017-01-01

    The efficiency of photoconductive (PC) devices, including terahertz detectors, is constrained by the bulk optical constants of PC materials. Here, we show that optical absorption in a PC layer can be modified substantially within a hybrid cavity containing nanoantennas and a Distributed Bragg Reflector. We find that a hybrid cavity, consisting of a GaAs PC layer of just 50 nm, can be used to absorb >75% of incident photons by trapping the light within the cavity. We provide an intuitive model, which describes the dependence of the optimum operation wavelength on the cavity thickness. We also find that the nanoantenna size is a critical parameter, small variations of which lead to both wavelength shifting and reduced absorption in the cavity, suggesting that impedance matching is key for achieving efficient absorption in the optically thin hybrid cavities.

  1. Central Tracking Detector Based on Scintillating Fibres

    CERN Multimedia

    2002-01-01

    Scintillating fibres form a reasonable compromise for central tracking detectors in terms of price, resolution, response time, occupancy and heat production. \\\\ \\\\ New fluorescents with large Stokes shifts have been produced, capable of working without wavelength shifters. Coherent multibundles have been developed to achieve high packing fractions. Small segments of tracker shell have been assembled and beam tests have confirmed expectations on spatial resolution. An opto-electronic delay line has been designed to delay the track patterns and enable coincidences with a first level trigger. Replacement of the conventional phosphor screen anode with a Si pixel chip is achieved. This tube is called ISPA-tube and has already been operated in beam tests with a scintillating fibres tracker. \\\\ \\\\ The aim of the proposal is to improve hit densities for small diameter fibres by increasing the fraction of trapped light, by reducing absorption and reflection losses, by reflecting light at the free fibre end, and by inc...

  2. Scintillating fiber detector

    CERN Document Server

    Vozak, Matous

    2016-01-01

    NA61 is one of the physics experiments at CERN dedicated to study hadron states coming from interactions of SPS beams with various targets. To determine the position of a secondary beam, three proportional chambers are placed along the beamline. However, these chambers tend to have slow response. In order to obtain more precise time information, use of another detector is being considered. Fast response and compact size is making scintillation fiber (SciFi) with silicon photomultiplier (Si-PM) read out a good candidate. This report is focused on analysing data from SciFi collected in a test beam at the beginning of July 2016.

  3. The ATLAS Detector Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Clark, P.J. [University of Edinburgh, School of Physics and Astronomy, James Clerk Maxwell Building, The Kings Buildings, Mayfield Road, Edinburgh EH9 3JZ (United Kingdom)

    2011-06-15

    We present the simulation software for the ATLAS experiment [G. Aad et al., The ATLAS Experiment at the CERN Large Hadron Collider, JINST 3 (2008), S08003] at the Large Hadron Collider [L. Evans and P. Bryant, LHC Machine, JINST 3 (2008), S08001]. The overall infrastructure and some selected features are discussed. In particular, the detector description, the interface to Geant4, event generator support, magnetic field integration improvements, pile-up and digitisation of overlapping events and fast simulation. Also described are performance studies, large scale production and the validation of the simulated output against recent data.

  4. The WELL Detector

    CERN Document Server

    Bellazzini, R; Brez, A; Gariano, G; Latronico, L; Lumb, N; Papanestis, A; Spandre, G; Massai, M M; Raffo, R; Spezziga, M A

    1999-01-01

    We introduce the WELL detector, a new type of position-sensitive gas proportional counter produced using advanced printed circuit board (PCB) technology. The WELL is based on a thin kapton foil, copp erclad on both sides. Charge amplifying micro-wells are etched into the first metal and kapton layers. These end on a micro-strip pattern which is defined on the second metal plane. The array of micr o-strips is used for read-out to obtain 1-D positional information. First results from our systematic assessment of this device are reported.

  5. Flexible composite radiation detector

    Science.gov (United States)

    Cooke, D. Wayne; Bennett, Bryan L.; Muenchausen, Ross E.; Wrobleski, Debra A.; Orler, Edward B.

    2006-12-05

    A flexible composite scintillator was prepared by mixing fast, bright, dense rare-earth doped powdered oxyorthosilicate (such as LSO:Ce, LSO:Sm, and GSO:Ce) scintillator with a polymer binder. The binder is transparent to the scintillator emission. The composite is seamless and can be made large and in a wide variety of shapes. Importantly, the composite can be tailored to emit light in a spectral region that matches the optimum response of photomultipliers (about 400 nanometers) or photodiodes (about 600 nanometers), which maximizes the overall detector efficiency.

  6. Microstructured silicon radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat; Derzon, Mark S.; Draper, Bruce L.

    2017-03-14

    A radiation detector comprises a silicon body in which are defined vertical pores filled with a converter material and situated within silicon depletion regions. One or more charge-collection electrodes are arranged to collect current generated when secondary particles enter the silicon body through walls of the pores. The pores are disposed in low-density clusters, have a majority pore thickness of 5 .mu.m or less, and have a majority aspect ratio, defined as the ratio of pore depth to pore thickness, of at least 10.

  7. PHENIX inner detectors

    Energy Technology Data Exchange (ETDEWEB)

    Allen, M.; Bennett, M.J.; Bobrek, M.; Boissevain, J.B.; Boose, S.; Bosze, E.; Britton, C.; Chang, J.; Chi, C.Y.; Chiu, M.; Conway, R.; Cunningham, R.; Denisov, A.; Deshpande, A.; Emery, M.S.; Enokizono, A.; Ericson, N.; Fox, B.; Fung, S.-Y.; Giannotti, P.; Hachiya, T.; Hansen, A.G.; Homma, K.; Jacak, B.V.; Jaffe, D.; Kang, J.H.; Kapustinsky, J.; Kim, S.Y.; Kim, Y.G.; Kohama, T.; Kroon, P.J.; Lenz, W.; Longbotham, N.; Musrock, M.; Nakamura, T.; Ohnishi, H.; Ryu, S.S.; Sakaguchi, A.; Seto, R.; Shiina, T.; Simpson, M.; Simon-Gillo, J.; Sondheim, W.E.; Sugitate, T.; Sullivan, J.P. E-mail: sullivan@lanl.gov; Hecke, H.W. van; Walker, J.W.; White, S.N.; Willis, P.; Xu, N

    2003-03-01

    The timing, location and particle multiplicity of a PHENIX collision are determined by the Beam-Beam Counters (BBC), the Multiplicity/Vertex Detector (MVD) and the Zero-Degree Calorimeters (ZDC). The BBCs provide both the time of interaction and position of a collision from the flight time of prompt particles. The MVD provides a measure of event particle multiplicity, collision vertex position and fluctuations in charged particle distributions. The ZDCs provide information on the most grazing collisions. A Normalization Trigger Counter (NTC) is used to obtain absolute cross-section measurements for p-p collisions. The BBC, MVD and NTC are described below.

  8. Neutron absorption constraints on the composition of 4 Vesta

    Science.gov (United States)

    Prettyman, Thomas H.; Mittlefehldt, David W.; Yamashita, Naoyuki; Beck, Andrew W.; Feldman, William C.; Hendricks, John S.; Lawrence, David J.; McCoy, Timothy J.; McSween, Harry Y.; Paplowski, Patrick N.; Reedy, Robert C.; Toplis, Michael J.; Le Corre, Lucille; Mizzon, Hugau; Reddy, Vishnu; Titus, Timothy N.; Raymond, Carol A.; Russell, Christopher T.

    2013-01-01

    Global maps of the macroscopic thermal neutron absorption cross section of Vesta's regolith by the Gamma Ray and Neutron Detector (GRaND) on board the NASA Dawn spacecraft provide constraints on the abundance and distribution of Fe, Ca, Al, Mg, and other rock-forming elements. From a circular, polar low-altitude mapping orbit, GRaND sampled the regolith to decimeter depths with a spatial resolution of about 300 km. At this spatial scale, the variation in neutron absorption is about seven times lower than that of the Moon. The observed variation is consistent with the range of absorption for howardite whole-rock compositions, which further supports the connection between Vesta and the howardite, eucrite, and diogenite meteorites. We find a strong correlation between neutron absorption and the percentage of eucritic materials in howardites and polymict breccias, which enables petrologic mapping of Vesta's surface. The distribution of basaltic eucrite and diogenite determined from neutron absorption measurements is qualitatively similar to that indicated by visible and near infrared spectroscopy. The Rheasilvia basin and ejecta blanket has relatively low absorption, consistent with Mg-rich orthopyroxene. Based on a combination of Fe and neutron absorption measurements, olivine-rich lithologies are not detected on the spatial scales sampled by GRaND. The sensitivity of GRaND to the presence of mantle material is described and implications for the absence of an olivine signature are discussed. High absorption values found in Vesta's “dark” hemisphere, where exogenic hydrogen has accumulated, indicate that this region is richer in basaltic eucrite, representative of Vesta's ancient upper crust.

  9. Neutron absorption constraints on the composition of 4 Vesta

    Science.gov (United States)

    Prettyman, Thomas H.; Mittlefehldt, David W.; Yamashita, Naoyuki; Beck, Andrew W.; Feldman, William C.; Hendricks, John S.; Lawrence, David J.; McCoy, Timothy J.; McSween, Harry Y.; Peplowski, Patrick N.; Reedy, Robert C.; Toplis, Michael J.; Corre, Lucille; Mizzon, Hugau; Reddy, Vishnu; Titus, Timothy N.; Raymond, Carol A.; Russell, Christopher T.

    2013-11-01

    Global maps of the macroscopic thermal neutron absorption cross section of Vesta's regolith by the Gamma Ray and Neutron Detector (GRaND) on board the NASA Dawn spacecraft provide constraints on the abundance and distribution of Fe, Ca, Al, Mg, and other rock-forming elements. From a circular, polar low-altitude mapping orbit, GRaND sampled the regolith to decimeter depths with a spatial resolution of about 300 km. At this spatial scale, the variation in neutron absorption is about seven times lower than that of the Moon. The observed variation is consistent with the range of absorption for howardite whole-rock compositions, which further supports the connection between Vesta and the howardite, eucrite, and diogenite meteorites. We find a strong correlation between neutron absorption and the percentage of eucritic materials in howardites and polymict breccias, which enables petrologic mapping of Vesta's surface. The distribution of basaltic eucrite and diogenite determined from neutron absorption measurements is qualitatively similar to that indicated by visible and near infrared spectroscopy. The Rheasilvia basin and ejecta blanket has relatively low absorption, consistent with Mg-rich orthopyroxene. Based on a combination of Fe and neutron absorption measurements, olivine-rich lithologies are not detected on the spatial scales sampled by GRaND. The sensitivity of GRaND to the presence of mantle material is described and implications for the absence of an olivine signature are discussed. High absorption values found in Vesta's "dark" hemisphere, where exogenic hydrogen has accumulated, indicate that this region is richer in basaltic eucrite, representative of Vesta's ancient upper crust.

  10. Infrared detectors for space applications

    Science.gov (United States)

    Fick, Wolfgang; Gassmann, Kai Uwe; Haas, Luis-Dieter; Haiml, Markus; Hanna, Stefan; Hübner, Dominique; Höhnemann, Holger; Nothaft, Hans-Peter; Thöt, Richard

    2013-12-01

    The motivation and intended benefits for the use of infrared (IR) detectors for space applications are highlighted. The actual status of state-of-the-art IR detectors for space applications is presented based on some of AIM's currently ongoing focal plane detector module developments covering the spectral range from the short-wavelength IR (SWIR) to the long-wavelength IR (LWIR) and very long-wavelength IR (VLWIR), where both imaging and spectroscopy applications will be addressed. In particular, the integrated detector cooler assemblies for a mid-wavelength IR (MWIR) push-broom imaging satellite mission, for the German hyperspectral satellite mission EnMAP and the IR detectors for the Sentinel 3 SLSTR will be elaborated. Additionally, dedicated detector modules for LWIR/VLWIR sounding, providing the possibility to have two different PVs driven by one ROIC, will be addressed.

  11. Scalar top study: Detector optimization

    Indian Academy of Sciences (India)

    C Milsténe; A Sopczak

    2007-11-01

    A vertex detector concept of the linear collider flavour identification (LCFI) collaboration, which studies pixel detectors for heavy quark flavour identification, has been implemented in simulations for -quark tagging in scalar top studies. The production and decay of scalar top quarks (stops) is particularly interesting for the development of the vertex detector as only two -quarks and missing energy (from undetected neutralinos) are produced for light stops. Previous studies investigated the vertex detector design in scenarios with large mass differences between stop and neutralino, corresponding to large visible energy in the detector. In this study we investigate the tagging performance dependence on the vertex detector design in a scenario with small visible energy for the international linear collider (ILC).

  12. Digital detectors for electron microscopy

    CERN Document Server

    Faruqi, A R

    2002-01-01

    Film has traditionally been used for recording images in transmission electron microscopes but there is an essential need for computer-interfaced electronic detectors. Cooled-CCD detectors, developed over the past few years, though not ideal, are increasingly used as the preferred detection system in a number of applications. We describe briefly the design of CCD-based detectors, along with their main properties, which have been used in electron crystallography. A newer detector design with a much bigger sensitive area, incorporating a 2x2 tiled array of CCDs with tapered fibre optics will overcome some of the limitations of existing CCD detectors. We also describe some preliminary results for 8 keV imaging, from (direct detection) silicon hybrid pixel detectors, which offer advantages over CCDs in terms of better spatial resolution, faster readout with minimal noise.

  13. Advances in the development of encapsulants for mercuric iodide X-ray detectors

    OpenAIRE

    Iwanczyk, J. S.; Wang, Y.J.; Bradley, J. G.; Albee, A. L.; Schnepple, W. F.

    1990-01-01

    Advances in the development of protective impermeable encapsulants with high transparency to ultra-low-energy X-rays for use on HgI_2 X-ray detectors are reported. Various X-ray fluorescence spectra from coated detectors are presented. The X-ray absorption in the encapsulants has been analyzed using characteristic radiation from various elements. Results suggest that low-energy cutoffs for the detectors are not determined solely by the encapsulating coatings presently employed but are also in...

  14. An analytic technique for the estimation of the light yield of a scintillation detector

    CERN Document Server

    Segreto, Ettore

    2011-01-01

    A simple model for the estimation of the light yield of a scintillation detector starting from the knowledge of its optical parameters and under general assumptions is developed. It is also shown how to take into account the effects related to Rayleigh scattering and absorption of the photons. The predictions of the model are benchmarked with the outcomes of a Monte Carlo simulation of a specific scintillation detector. The case of a real scintillation detector with internal surface covered by wavelength-shifter is explicitly treated and the model prediction is compared with the measured light yield.

  15. Particle Identification: Time-of-Flight, Cherenkov and Transition Radiation Detectors - Particle Detectors and Detector Systems

    CERN Document Server

    Ullaland, O

    2011-01-01

    Particle Identification: Time-of-Flight, Cherenkov and Transition Radiation Detectors in 'Particle Detectors and Detector Systems', part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B1: Detectors for Particles and Radiation. Part 1: Principles and Methods'. This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Section '3.3 Particle Identification: Time-of-Flight, Cherenkov and Transition Radiation Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.3 Particle Identification: Time-of-Flight, Cherenkov and Transition Radiation Detectors 3.3.1 Introduction 3.3.2 Time of Flight Measurements 3.3.2.1 Scintillator hodoscopes 3.3.2.2 Parallel plate ToF detectors 3.3.3 Cherenkov Radiation 3.3.3.1 ...

  16. The FastGas detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E.; Dalgliesh, R.M. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.u [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Holt, S.A.; McPhail, D.J. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M.; Spill, E.J.; Stephenson, R. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom)

    2010-04-21

    The development and testing of the FastGas neutron detector is described. Based on a Gas Microstrip Chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing {sup 3}He tubes for specular reflectometry, currently in use on the ISIS reflectometer instruments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  17. The 4th concept detector

    Indian Academy of Sciences (India)

    John Hauptman

    2007-12-01

    The 4th concept detector consists of four detector subsystems, a small-pixel vertex detector, a high-resolution TPC, a new multiple-readout fiber calorimeter and a new dual-solenoid iron-free muon system. We discuss the design of a comprehensive facility that measures and identifies all partons of the standard model, including hadronic → and → decays, with high precision and high e±ciency. We emphasis here the calorimeter and muon systems.

  18. First detectors at the ISR

    CERN Multimedia

    1971-01-01

    Some of the first detectors at the ISR. A CERN/Rome team was looking at proton scattering at very small angles to the beam direction. A detector known as a "Roman pot" is in the foreground on the left. An Aachen/CERN/Genoa/Harvard/Turin team was looking at wider angles with the detectors seen branching off from the rings on the right.

  19. Decoherence of the Unruh detector

    CERN Document Server

    Demers, G

    1995-01-01

    As it is well known, the Minkowski vacuum appears thermally populated to a quantum mechanical detector on a uniformly accelerating course. We investigate how this thermal radiation may contribute to the classical nature of the detector's trajectory through the criteria of decoherence. An uncertainty-type relation is obtained for the detector involving the fluctuation in temperature, the time of flight and the coupling to the bath.

  20. The CMS detector before closure

    CERN Multimedia

    Patrice Loiez

    2006-01-01

    The CMS detector before testing using muon cosmic rays that are produced as high-energy particles from space crash into the Earth's atmosphere generating a cascade of energetic particles. After closing CMS, the magnets, calorimeters, trackers and muon chambers were tested on a small section of the detector as part of the magnet test and cosmic challenge. This test checked the alignment and functionality of the detector systems, as well as the magnets.

  1. Position resolution of a double junction superconductive detector based on a single material

    Science.gov (United States)

    Samedov, V. V.

    2008-02-01

    The Naples group from Istituto Nazionale di Fisica Nucleare presented the results of theoretical investigations of a new class of superconductive radiation detectors - double junction superconductive detector based on a single material [1]. In such detectors, the absorption of energy occurs in a long superconductive strip while two superconductive tunnel junctions positioned at the ends of the strip provide the readout of the signals. The main peculiarity of this type of detectors is that they are based on a single superconducting material, i.e., without trapping layers at the ends of the strip. In this paper, general approach to the position resolution of this type of detectors has been attempted. The formula for the position resolution is derived. It is shown that the application of the aluminium for the absorber may be the best possible way not only due to the small gap energy, but also mainly for STJ fabrication technology based on the aluminium oxide tunnel barrier.

  2. High Speed Travelling Wave Single-Photon Detectors With Near-Unity Quantum Efficiency

    CERN Document Server

    Pernice, W; Minaeva, O; Li, M; Goltsman, G N; Sergienko, A V; Tang, H X

    2011-01-01

    Ultrafast, high quantum efficiency single photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. Close-to-unity photon detection efficiency is essential for scalable measurement-based quantum computation, quantum key distribution, and loophole-free Bell experiments. However, imperfect modal matching and finite photon absorption rates have usually limited the maximum attainable detection efficiency of single photon detectors. Here we demonstrate a superconducting nanowire detector atop nanophotonic waveguides and achieve single photon detection efficiency up to 94% at telecom wavelengths. Our detectors are fully embedded in a scalable, low loss silicon photonic circuit and provide ultrashort timing jitter of 18ps at multi-GHz detection rates. Exploiting this high temporal resolution we demonstrate ballistic photon transport in silicon ring resonators. The direct implementation of such a detector with high quantum efficiency, high detection speed and low ji...

  3. MUON DETECTORS: CSC

    CERN Multimedia

    Richard Breedon

    Following the opening of the CMS detector, commissioning of the cathode strip chamber (CSC) system resumed in earnest. Some on-chamber electronics problems could be fixed on the positive endcap when each station became briefly accessible as the steel yokes were peeled off. There was no opportunity to work on the negative endcap chambers during opening; this had to wait instead until the yokes were again separated and the stations accessible during closing. In March, regular detector-operating shifts were resumed every weekday evening during which Local Runs were taken using cosmic rays to monitor and validate repairs and improvements that had taken place during the day. Since April, the CSC system has been collecting cosmic data under shift supervision 24 hours a day on weekdays, and 24/7 operation began in early June. The CSC system arranged shifts for continuous running in the entire first half of 2009. One reward of this effort is that every chamber of the CSC system is alive and recording events. There...

  4. ATLAS Detector Upgrade Prospects

    Science.gov (United States)

    Dobre, M.; ATLAS Collaboration

    2017-01-01

    After the successful operation at the centre-of-mass energies of 7 and 8 TeV in 2010-2012, the LHC was ramped up and successfully took data at the centre-of-mass energies of 13 TeV in 2015 and 2016. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, which will deliver of the order of five times the LHC nominal instantaneous luminosity along with luminosity levelling. The ultimate goal is to extend the dataset from about few hundred fb ‑1 expected for LHC running by the end of 2018 to 3000 fb ‑1 by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of extensions to larger pseudorapidity, particularly in tracking and muon systems. This report summarizes various improvements to the ATLAS detector required to cope with the anticipated evolution of the LHC luminosity during this decade and the next. A brief overview is also given on physics prospects with a pp centre-of-mass energy of 14 TeV.

  5. MUON DETECTORS: CSC

    CERN Multimedia

    J. Hauser

    2011-01-01

    The earliest collision data in 2011 already show that the CSC detector performance is very similar to that seen in 2010. That is discussed in the DPG write-up elsewhere in this Bulletin. This report focuses on a few operational developments, the ME1/1 electronics replacement project, and the preparations at CERN for building the fourth station of CSC chambers ME4/2. During the 2010 LHC run, the CSC detector ran smoothly for the most part and yielded muon triggers and data of excellent quality. Moreover, no major operational problems were found that needed to be fixed during the Extended Technical Stop. Several improvements to software and configuration were however made. One such improvement is the automation of recovery from chamber high-voltage trips. The algorithm, defined by chamber experts, uses the so-called "Expert System" to analyse the trip signals sent from DCS and, based on the frequency and the timing of the signals, respond appropriately. This will make the central DCS shifters...

  6. MUON DETECTORS: RPC

    CERN Multimedia

    G. Iaselli

    During the last 3 months the RPC group has made impressive improvements in the refinement of the operation tools and understanding of the detector. The full barrel and part of the plus end cap participated systematically to global runs producing millions of trigger on cosmics. The main monitoring tools were robust and efficient in controlling the detector and in diagnosis of problems. After the refinement of the synchronization procedure, detailed studies of the chamber performances, as a function of high voltage and front-end threshold, were pursued. In parallel, new tools for the prompt analysis were developed which have enabled a fast check of the data at the CMS Centre. This effort has been very valuable since it has helped in discovering many minor bugs in the reconstruction software and database which are now being fixed. Unfortunately, a large part of the RE2 station has developed increasing operational current. Some preliminary investigation leads to the conclusion that the serial gas circulation e...

  7. MUON DETECTORS: DT

    CERN Multimedia

    Marco Dallavalle

    2013-01-01

    The DT group is undertaking substantial work both for detector maintenance and for detec-tor upgrade. Maintenance interventions on chambers and minicrates require close collaboration between DT, RPC and HO, and are difficult because they depend on the removal of thermal shields and cables on the front and rear of the chambers in order to gain access. The tasks are particularly critical on the central wheel due to the presence of fixed services. Several interventions on the chambers require extraction of the DT+RPC package: a delicate operation due to the very limited space for handling the big chambers, and the most dangerous part of the DT maintenance campaign. The interventions started in July 2013 and will go on until spring 2014. So far out of the 16 chambers with HV problems, 13 have been already repaired, with a global yield of 217 recovered channels. Most of the observed problems were due to displacement of impurities inside the gaseous volume. For the minicrates and FE, repairs occurred on 22 chambe...

  8. MUON DETECTORS: RPC

    CERN Multimedia

    G. Iaselli.

    Substantial progress has been made on the RPC system resulting in a high standard of operation. Impressive improvements have been made in the online software and DCS PVSS protocols that ensure robustness of the configuration phase and reliability of the detector monitoring tasks. In parallel, an important upgrade of CCU ring connectivity was pursued to avoid noise pick-up and consequent  data transmission errors during operation with magnetic field. While the barrel part is already well synchronized thanks to the long cosmics runs, some refinements are still required on the forward part. The "beam splashes" have been useful to cross check  the existing delay constants, but further efforts will be made as soon as a substantial sample of beam-halo events is available. Progress has been made on early detector performance studies. The RPC DQM tool is being extensively used and minor bugs have been found. More plots have been added and more people have been tr...

  9. PAU camera: detectors characterization

    Science.gov (United States)

    Casas, Ricard; Ballester, Otger; Cardiel-Sas, Laia; Castilla, Javier; Jiménez, Jorge; Maiorino, Marino; Pío, Cristóbal; Sevilla, Ignacio; de Vicente, Juan

    2012-07-01

    The PAU Camera (PAUCam) [1,2] is a wide field camera that will be mounted at the corrected prime focus of the William Herschel Telescope (Observatorio del Roque de los Muchachos, Canary Islands, Spain) in the next months. The focal plane of PAUCam is composed by a mosaic of 18 CCD detectors of 2,048 x 4,176 pixels each one with a pixel size of 15 microns, manufactured by Hamamatsu Photonics K. K. This mosaic covers a field of view (FoV) of 60 arcmin (minutes of arc), 40 of them are unvignetted. The behaviour of these 18 devices, plus four spares, and their electronic response should be characterized and optimized for the use in PAUCam. This job is being carried out in the laboratories of the ICE/IFAE and the CIEMAT. The electronic optimization of the CCD detectors is being carried out by means of an OG (Output Gate) scan and maximizing it CTE (Charge Transfer Efficiency) while the read-out noise is minimized. The device characterization itself is obtained with different tests. The photon transfer curve (PTC) that allows to obtain the electronic gain, the linearity vs. light stimulus, the full-well capacity and the cosmetic defects. The read-out noise, the dark current, the stability vs. temperature and the light remanence.

  10. Advanced Radiation Detector Development

    Energy Technology Data Exchange (ETDEWEB)

    The University of Michigan

    1998-07-01

    Since our last progress report, the project at The University of Michigan has continued to concentrate on the development of gamma ray spectrometers fabricated from cadmium zinc telluride (CZT). This material is capable of providing energy resolution that is superior to that of scintillation detectors, while avoiding the necessity for cooling associated with germanium systems. In our past reports, we have described one approach (the coplanar grid electrode) that we have used to partially overcome some of the major limitations on charge collection that is found in samples of CZT. This approach largely eliminates the effect of hole motion in the formation of the output signal, and therefore leads to pulses that depend only on the motion of a single carrier (electrons). Since electrons move much more readily through CZT than do holes, much better energy resolution can be achieved under these conditions. In our past reports, we have described a 1 cm cube CZT spectrometer fitted with coplanar grids that achieved an energy resolution of 1.8% from the entire volume of the crystal. This still represents, to our knowledge, the best energy resolution ever demonstrated in a CZT detector of this size.

  11. MUON DETECTORS: DT

    CERN Multimedia

    C. Fernandez Bedoya and M. Dallavalle

    2010-01-01

    The DT system operation since the 2010 LHC start up is remarkably smooth.
 All parts of the system have behaved very satisfactorily in the last two months of operation with LHC pp collisions. Disconnected HV channels remain at the level of 0.1%, and the loss in detector acceptance because of failures in the readout and Trigger electronics is about 0.4%. The DT DCS-LHC handshake mechanism, which was strengthened after the short 2009 LHC run, operates without major problems. A problem arose with the opto-receivers of the trigger links connecting the detector to USC; the receivers would unlock from transmission for specific frequencies of the LHC lock, in particular during the LHC ramp. For relocking the TX and RX a “re-synch” command had to be issued. The source of the problem has been isolated and cured in the Opto-RX boards and now the system is stable. The Theta trigger chain also has been commissioned and put in operation. Several interventions on the system have been made, pro...

  12. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2011-01-01

    The RPC muon detector and trigger are working very well, contributing positively to the high quality of CMS data. Most of 2011 has been used to improve the stability of our system and the monitoring tools used online and offline by the shifters and experts. The high-voltage working point is corrected, chamber-by-chamber, for pressure variation since July 2011. Corrections are applied at PVSS level during the stand-by mode (no collision) and are not changed until the next fill. The single detector calibration, HV scan, of February and the P-correction described before were very important steps towards fine-tuning the stability of the RPC performances. A very detailed analysis of the RPC performances is now ongoing and from preliminary results we observe an important improvements of the cluster size stability in time. The maximum oscillation of the cluster size run by run is now about 1%. At the same time we are not observing the same stability in the detection efficiency that shows an oscillation of about ...

  13. MUON DETECTORS: DT

    CERN Document Server

    Marco Dallavalle

    2012-01-01

      Although the year 2012 is the third year without access to the chambers and the Front-End electronics, the fraction of good channels is still very high at 99.1% thanks also to the constant care provided by the on-site operation team. The downtime caused to CMS as a consequence of DT failures is to-date <2%. The intervention on the LV power supplies, which required a large number of CAEN modules (137 A3050, 13 A3100, and 3 MAO) to be removed from the detector, reworked and tested during this Year-End Technical Stop, can now, after a few months of stable operation of the LV, be declared to have solved once-and-for-all the persistent problem with the overheating LV Anderson connectors. Another piece of very good news is that measurements of the noise from single-hit rate outside the drift-time box as a function of the LHC luminosity show that the noise rate and distribution are consistent with expectations of the simulations in the Muon TDR, which have guided the detector design and constru...

  14. The TALE Fluorescence Detectors

    Science.gov (United States)

    Jui, Charles

    2009-05-01

    The TALE fluorescence detectors are designed to extend the threshold for fluorescence observation by TA down to 3x10^16 eV. It will comprise two main components. The first is a set of 24 telescopes working in stereo, with an existing TA FD station at ˜6 km separation. These will cover between 3-31 degrees in elevation and have azimuthal coverage maximizing the stereo aperture in the 10^18-10^19 eV energy range. The second component consists of 15 telescopes equipped with 4m diameter mirrors and covering the sky between 31 and 73 degrees in elevation. The larger mirror size pushes the physics threshold down to 3x10^16 eV, and provides view of the shower maximum for the lower energy events. The Tower detector will cover one quadrant in azimuth and operate in hybrid mode with the TALE infill array to provide redundant composition measurements from both shower maximum information and muon-to-electron ratio.

  15. VNR CMS Pixel detector replacement

    CERN Document Server

    2017-01-01

    Joel Butler, spokesperson of the CMS collaboration explains how a team from many different partner institutes installed a new detector in CMS. This detector is the silicon pixel detector and they’ve been working on it for about five years, to replace one of our existing detectors. This detectors measures particles closer to the beam than any of the other components of this huge detector behind me. It gives us the most precise picture of tracks as they come out of the collisions and expand and travel through the detector. This particular device has twice as many pixels, 120 million, as opposed to about 68 million in the old detector and it can take data faster and pump it out to the analysis more quickly. 00’53’’ Images of the descent, insertion and installation of first piece of the Pixel detector on Tue Feb 28. Images of the descent, insertion and installation of second piece of the Pixel and the two cylinders being joined.

  16. Tomography of Spatial Mode Detectors

    CERN Document Server

    Bobrov, Ivan; Markov, Anton; Straupe, Stanislav; Kulik, Sergey

    2014-01-01

    Transformation and detection of photons in higher-order spatial modes usually requires complicated holographic techniques. Detectors based on spatial holograms suffer from non-idealities and should be carefully calibrated. We report a novel method for analyzing the quality of projective measurements in spatial mode basis inspired by quantum detector tomography. It allows us to calibrate the detector response using only gaussian beams. We experimentally investigate the inherent inaccuracy of the existing methods of mode transformation and provide a full statistical reconstruction of the POVM (positive operator valued measure) elements for holographic spatial mode detectors.

  17. Position-sensitive superconductor detectors

    Science.gov (United States)

    Kurakado, M.; Taniguchi, K.

    2016-12-01

    Superconducting tunnel junction (STJ) detectors and superconducting transition- edge sensors (TESs) are representative superconductor detectors having energy resolutions much higher than those of semiconductor detectors. STJ detectors are thin, thereby making it suitable for detecting low-energy X rays. The signals of STJ detectors are more than 100 times faster than those of TESs. By contrast, TESs are microcalorimeters that measure the radiation energy from the change in the temperature. Therefore, signals are slow and their time constants are typically several hundreds of μs. However, TESs possess excellent energy resolutions. For example, TESs have a resolution of 1.6 eV for 5.9-keV X rays. An array of STJs or TESs can be used as a pixel detector. Superconducting series-junction detectors (SSJDs) comprise multiple STJs and a single-crystal substrate that acts as a radiation absorber. SSJDs are also position sensitive, and their energy resolutions are higher than those of semiconductor detectors. In this paper, we give an overview of position-sensitive superconductor detectors.

  18. Solid-state, flat-panel, digital radiography detectors and their physical imaging characteristics.

    Science.gov (United States)

    Cowen, A R; Kengyelics, S M; Davies, A G

    2008-05-01

    Solid-state, digital radiography (DR) detectors, designed specifically for standard projection radiography, emerged just before the turn of the millennium. This new generation of digital image detector comprises a thin layer of x-ray absorptive material combined with an electronic active matrix array fabricated in a thin film of hydrogenated amorphous silicon (a-Si:H). DR detectors can offer both efficient (low-dose) x-ray image acquisition plus on-line readout of the latent image as electronic data. To date, solid-state, flat-panel, DR detectors have come in two principal designs, the indirect-conversion (x-ray scintillator-based) and the direct-conversion (x-ray photoconductor-based) types. This review describes the underlying principles and enabling technologies exploited by these designs of detector, and evaluates their physical imaging characteristics, comparing performance both against each other and computed radiography (CR). In standard projection radiography indirect conversion DR detectors currently offer superior physical image quality and dose efficiency compared with direct conversion DR and modern point-scan CR. These conclusions have been confirmed in the findings of clinical evaluations of DR detectors. Future trends in solid-state DR detector technologies are also briefly considered. Salient innovations include WiFi-enabled, portable DR detectors, improvements in x-ray absorber layers and developments in alternative electronic media to a-Si:H.

  19. Sabine absorption coefficients to random incidence absorption coefficients

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2014-01-01

    Absorption coefficients measured by the chamber method are referred to as Sabine absorption coefficients, which sometimes exceed unity due to the finite size of a specimen and non-uniform intensity in the test chamber. In this study, several methods that convert Sabine absorption coefficients...... into random incidence absorption coefficients for porous absorbers are investigated. Two optimization-based conversion methods are suggested: the surface impedance estimation for locally reacting absorbers and the flow resistivity estimation for extendedly reacting absorbers. The suggested conversion methods...

  20. Crosstalk study of near infrared InGaAs detectors

    Science.gov (United States)

    Li, Xue; Tang, Hengjing; Li, Tao; Fan, Cui; Shao, Xiumei; Li, Jianwei; Wei, Jun; Gong, Haimei

    2016-05-01

    Crosstalk characteristics of high density FPA detectors attract widespread attention in the application of electro-optical systems. Crosstalk characteristics of near-infrared (NIR) InGaAs photodiodes and focal plane arrays (FPAs) were studied in this paper. The mesa type detector was investigated by using laser beam induced current technique (LBIC) to measure the absorption outside the designed photosensitive area, and the results show that the excess absorption enlarges the crosstalk of the adjacent pixels. The structure optimization using the effective absorption layer between the pixels can effectively reduce the crosstalk to 2.5%. The major crosstalk components of the optimization photodiode come from the electronic signal caused by carrier lateral diffusion. For the planar type detectors, test structures were used to compare the crosstalk of different structures, and the guard ring structure shows good suppression of the crosstalk. Then the back-illuminated 32x32 InGaAs photodiodes with 30μm pitch were designed, and LBIC was used to measure its lateral diffusion of the effective carriers and fill factor of photosensitive area. The results indicate that the fill factor of detectors can reach up to 98% when the diffusion region is optimized, and the minimum response exists between two neighborhood pixels. Based on these crosstalk measurement results and optimizing structure designs, the linear InGaAs photodiodes were designed and thus the InGaAs FPA assembly was fabricated. The assembly shows higher electro-optical performance and good improvement on crosstalk. The assembly was applied in infrared imaging system and modulation transfer function (MTF) of FPA assembly was calculated to be above 0.50. The clear image based on FPA assembly was obtained.

  1. Diffuse interstellar absorption bands

    Institute of Scientific and Technical Information of China (English)

    XIANG FuYuan; LIANG ShunLin; LI AiGen

    2009-01-01

    The diffuse interstellar bands (DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s, the exact nature of DIBs still remains unclear. This article reviews the history of the detec-tions of DIBs in the Milky Way and external galaxies, the major observational characteristics of DIBs, the correlations or anti-correlations among DIBs or between DIBs and other interstellar features (e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise), and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

  2. Diffuse interstellar absorption bands

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

  3. The HI absorption "Zoo"

    Science.gov (United States)

    Geréb, K.; Maccagni, F. M.; Morganti, R.; Oosterloo, T. A.

    2015-03-01

    We present an analysis of the H I 21 cm absorption in a sample of 101 flux-selected radio AGN (S1.4 GHz> 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). We detect H I absorption in 32 objects (30% of the sample). In a previous paper, we performed a spectral stacking analysis on the radio sources, while here we characterize the absorption spectra of the individual detections using the recently presented busy function. The H I absorption spectra show a broad variety of widths, shapes, and kinematical properties. The full width half maximum (FWHM) of the busy function fits of the detected H I lines lies in the range 32 km s-1 200 km s-1). We study the kinematical and radio source properties of each group, with the goal of identifying different morphological structures of H I. Narrow lines mostly lie at the systemic velocity and are likely produced by regularly rotating H I disks or gas clouds. More H I disks can be present among galaxies with lines of intermediate widths; however, the H I in these sources is more unsettled. We study the asymmetry parameter and blueshift/redshift distribution of the lines as a function of their width. We find a trend for which narrow profiles are also symmetric, while broad lines are the most asymmetric. Among the broadest lines, more lines appear blueshifted than redshifted, similarly to what was found by previous studies. Interestingly, symmetric broad lines are absent from the sample. We argue that if a profile is broad, it is also asymmetric and shifted relative to the systemic velocity because it is tracing unsettled H I gas. In particular, besides three of the broadest (up to FW20 = 825 km s-1) detections, which are associated with gas-rich mergers, we find three new cases of profiles with blueshifted broad wings (with FW20 ≳ 500 km s-1) in high radio power AGN. These detections are good candidates for being HI outflows. Together with the known cases of outflows already included in the sample (3C 293 and

  4. High resolution, multiple-energy linear sweep detector for x-ray imaging

    Science.gov (United States)

    Perez-Mendez, V.; Goodman, C.A.

    1996-08-20

    Apparatus is disclosed for generating plural electrical signals in a single scan in response to incident X-rays received from an object. Each electrical signal represents an image of the object at a different range of energies of the incident X-rays. The apparatus comprises a first X-ray detector, a second X-ray detector stacked upstream of the first X-ray detector, and an X-ray absorber stacked upstream of the first X-ray detector. The X-ray absorber provides an energy-dependent absorption of the incident X-rays before they are incident at the first X-ray detector, but provides no absorption of the incident X-rays before they are incident at the second X-ray detector. The first X-ray detector includes a linear array of first pixels, each of which produces an electrical output in response to the incident X-rays in a first range of energies. The first X-ray detector also includes a circuit that generates a first electrical signal in response to the electrical output of each of the first pixels. The second X-ray detector includes a linear array of second pixels, each of which produces an electrical output in response to the incident X-rays in a second range of energies, broader than the first range of energies. The second X-ray detector also includes a circuit that generates a second electrical signal in response to the electrical output of each of the second pixels. 12 figs.

  5. PET detector modules based on novel detector technologies

    Energy Technology Data Exchange (ETDEWEB)

    Moses, W.W.; Derenzo, S.E.; Budinger, T.F.

    1994-05-01

    A successful PET detector module must identify 511 keV photons with: high efficiency (>85%), high spatial resolution (<5 mm fwhm), low cost (<$600 / in{sup 2}), low dead time (<4 {mu}s in{sup 2}), good timing resolution (<5 ns fwhm for conventional PET, <200 ps fwhm for time of flight), and good energy resolution (<100 keV fwhm), where these requirements are listed in decreasing order of importance. The ``high efficiency`` requirement also implies that the detector modules must pack together without inactive gaps. Several novel and emerging radiation detector technologies could improve the performance of PET detectors. Avalanche photodiodes, PIN photodiodes, metal channel dynode photomultiplier tubes, and new scintillators all have the potential to improve PET detectors significantly.

  6. Active feedback regulation of a Michelson interferometer to achieve zero-background absorption measurements.

    Science.gov (United States)

    Lundin, Patrik; Guan, Zuguang; Svanberg, Sune

    2011-01-20

    An active phase-controlling scheme based on a proportional-integral-derivative-controlled piezoelectric transducer is presented with the purpose of stabilizing a quasi-zero-background absorption spectrometer. A fiber-based balanced Michelson interferometer is used, and absorption due to a gas sample in one of its arms results in an increased light signal to a detector, which otherwise, thanks to destructive interference, experiences a very low light level. With the presented approach, the sensitivity of already potent absorption measurement techniques, e.g., based on modulation, could be improved even further.

  7. Absorption intestinale des vitamines liposolubles

    OpenAIRE

    Reboul Emmanuelle

    2011-01-01

    The molecular mechanisms of fat-soluble vitamin intestinal absorption remain partly unknown, despite the fact that a better understanding of this process would certainly allow to improve their bioavailability. If their digestion-absorption process follows the fate of lipids globally, the recent discovery of membranes proteins involved in their absorption questioned the established dogmas. These new data should be taken into account to avoid dietary or drug interactions that may limit some fat...

  8. High optical absorption in graphene

    CERN Document Server

    Apell, S P; Hägglund, C

    2012-01-01

    A simple analysis is performed for the absorption properties of graphene; sandwiched between two media. For a proper choice of media and graphene doping/gating one can approach 50-100% absorption in the GHz-THz range for the one atom thick material. This absorption is controlled by a characteristic chemical potential which depends only on carrier life-time and the indexes of refraction of the dielectric embedding.

  9. Absorption intestinale des vitamines liposolubles

    Directory of Open Access Journals (Sweden)

    Reboul Emmanuelle

    2011-03-01

    Full Text Available The molecular mechanisms of fat-soluble vitamin intestinal absorption remain partly unknown, despite the fact that a better understanding of this process would certainly allow to improve their bioavailability. If their digestion-absorption process follows the fate of lipids globally, the recent discovery of membranes proteins involved in their absorption questioned the established dogmas. These new data should be taken into account to avoid dietary or drug interactions that may limit some fatsoluble vitamin bioavailability.

  10. Neutron detector and fabrication method thereof

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Harish B.; Nagarkar, Vivek V.; Ovechkina, Olena E.

    2016-08-16

    A neutron detector and a method for fabricating a neutron detector. The neutron detector includes a photodetector, and a solid-state scintillator operatively coupled to the photodetector. In one aspect, the method for fabricating a neutron detector includes providing a photodetector, and depositing a solid-state scintillator on the photodetector to form a detector structure.

  11. MBE HgCdTe heterostructure detectors

    Science.gov (United States)

    Schulman, Joel N.; Wu, Owen K.

    1990-01-01

    HgCdTe has been the mainstay for medium (3 to 5 micron) and long (10 to 14 micron) wavelength infrared detectors in recent years. Conventional growth and processing techniques are continuing to improve the material. However, the additional ability to tailor composition and placement of doped layers on the tens of angstroms scale using molecular beam epitaxy (MBE) provides the opportunity for new device physics and concepts to be utilized. MBE-based device structures to be discussed here can be grouped into two categories: tailored conventional structures and quantum structures. The tailored conventional structures are improvements on familiar devices, but make use of the ability to create layers of varying composition, and thus band gap, at will. The heterostructure junction can be positioned independently of doping p-n junctions. This allows the small band gap region in which the absorption occurs to be separated from a larger band gap region in which the electric field is large and where unwanted tunneling can occur. Data from hybrid MBE/liquid phase epitaxy (LPE)/bulk structures are given. Quantum structures include the HgTe-CdTe superlattice, in which the band gap and transport can be controlled by alternating thin layers (tens of angstroms thick) of HgTe and CdTe. The superlattice has been shown to exhibit behavior which is non-alloy like, including very high hole mobilities, two-dimensional structure in the absorption coefficient, resonant tunneling, and anisotropic transport.

  12. X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

    This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

  13. Particle detector spatial resolution

    Science.gov (United States)

    Perez-Mendez, V.

    1992-12-15

    Method and apparatus for producing separated columns of scintillation layer material, for use in detection of X-rays and high energy charged particles with improved spatial resolution is disclosed. A pattern of ridges or projections is formed on one surface of a substrate layer or in a thin polyimide layer, and the scintillation layer is grown at controlled temperature and growth rate on the ridge-containing material. The scintillation material preferentially forms cylinders or columns, separated by gaps conforming to the pattern of ridges, and these columns direct most of the light produced in the scintillation layer along individual columns for subsequent detection in a photodiode layer. The gaps may be filled with a light-absorbing material to further enhance the spatial resolution of the particle detector. 12 figs.

  14. Radiation detector with spodumene

    Energy Technology Data Exchange (ETDEWEB)

    D' Amorim, Raquel Aline P.O.; Lima, Hestia Raissa B.R.; Souza, Susana O. [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica; Sasaki, Jose M., E-mail: sasaki@fisica.ufc.b [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Fisica; Caldas, Linda V.E., E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    In this work, {beta}-spodumene potentiality as a radiation detector was evaluated by making use of thermoluminescence (TL) and thermally stimulated exoelectron emission (TSEE) techniques. The pellets were obtained from the {beta}-spodumene powder mixed with Teflon followed by a sintering process of thermal treatments of 300 deg/30 min and 400 deg/1.5 h. The samples were irradiated in standard gamma radiation beams with doses between 5 Gy and 10 kGy. The TL emission curve showed a prominent peak at 160 deg and in the case of TSEE a prominent peak at 145 Celsius approximately. Initial results show that the material is promising for high-dose dosimetry. (author)

  15. Direction sensitive neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Ahlen, Steven; Fisher, Peter; Dujmic, Denis; Wellenstein, Hermann F.; Inglis, Andrew

    2017-01-31

    A neutron detector includes a pressure vessel, an electrically conductive field cage assembly within the pressure vessel and an imaging subsystem. A pressurized gas mixture of CF.sub.4, .sup.3He and .sup.4He at respective partial pressures is used. The field cage establishes a relatively large drift region of low field strength, in which ionization electrons generated by neutron-He interactions are directed toward a substantially smaller amplification region of substantially higher field strength in which the ionization electrons undergo avalanche multiplication resulting in scintillation of the CF.sub.4 along scintillation tracks. The imaging system generates two-dimensional images of the scintillation patterns and employs track-finding to identify tracks and deduce the rate and direction of incident neutrons. One or more photo-multiplier tubes record the time-profile of the scintillation tracks permitting the determination of the third coordinate.

  16. Pixelated gamma detector

    Energy Technology Data Exchange (ETDEWEB)

    Dolinsky, Sergei Ivanovich; Yanoff, Brian David; Guida, Renato; Ivan, Adrian

    2016-12-27

    A pixelated gamma detector includes a scintillator column assembly having scintillator crystals and optical transparent elements alternating along a longitudinal axis, a collimator assembly having longitudinal walls separated by collimator septum, the collimator septum spaced apart to form collimator channels, the scintillator column assembly positioned adjacent to the collimator assembly so that the respective ones of the scintillator crystal are positioned adjacent to respective ones of the collimator channels, the respective ones of the optical transparent element are positioned adjacent to respective ones of the collimator septum, and a first photosensor and a second photosensor, the first and the second photosensor each connected to an opposing end of the scintillator column assembly. A system and a method for inspecting and/or detecting defects in an interior of an object are also disclosed.

  17. Subnanosecond Scintillation Detector

    Science.gov (United States)

    Hoenk, Michael (Inventor); Hennessy, John (Inventor); Hitlin, David (Inventor)

    2017-01-01

    A scintillation detector, including a scintillator that emits scintillation; a semiconductor photodetector having a surface area for receiving the scintillation, wherein the surface area has a passivation layer configured to provide a peak quantum efficiency greater than 40% for a first component of the scintillation, and the semiconductor photodetector has built in gain through avalanche multiplication; a coating on the surface area, wherein the coating acts as a bandpass filter that transmits light within a range of wavelengths corresponding to the first component of the scintillation and suppresses transmission of light with wavelengths outside said range of wavelengths; and wherein the surface area, the passivation layer, and the coating are controlled to increase the temporal resolution of the semiconductor photodetector.

  18. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez

    2011-01-01

    A new set of muon alignment constants was approved in August. The relative position between muon chambers is essentially unchanged, indicating good detector stability. The main changes concern the global positioning of the barrel and of the endcap rings to match the new Tracker geometry. Detailed studies of the differences between track-based and optical alignment of DTs have proven to be a valuable tool for constraining Tracker alignment weak modes, and this information is now being used as part of the alignment procedure. In addition to the “split-cosmic” analysis used to investigate the muon momentum resolution at high momentum, a new procedure based on reconstructing the invariant mass of di-muons from boosted Zs is under development. Both procedures show an improvement in the momentum precision of Global Muons with respect to Tracker-only Muons. Recent developments in track-based alignment include a better treatment of the tails of residual distributions and accounting for correla...

  19. Chemical aerosol Raman detector

    Science.gov (United States)

    Aggarwal, R. L.; Farrar, L. W.; Di Cecca, S.; Amin, M.; Perkins, B. G.; Clark, M. L.; Jeys, T. H.; Sickenberger, D. W.; D'Amico, F. M.; Emmons, E. D.; Christesen, S. D.; Kreis, R. J.; Kilper, G. K.

    2017-03-01

    A sensitive chemical aerosol Raman detector (CARD) has been developed for the trace detection and identification of chemical particles in the ambient atmosphere. CARD includes an improved aerosol concentrator with a concentration factor of about 40 and a CCD camera for improved detection sensitivity. Aerosolized isovanillin, which is relatively safe, has been used to characterize the performance of the CARD. The limit of detection (SNR = 10) for isovanillin in 15 s has been determined to be 1.6 pg/cm3, which corresponds to 6.3 × 109 molecules/cm3 or 0.26 ppb. While less sensitive, CARD can also detect gases. This paper provides a more detailed description of the CARD hardware and detection algorithm than has previously been published.

  20. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    Z. Szillasi and G. Gomez.

    2013-01-01

    When CMS is opened up, major components of the Link and Barrel Alignment systems will be removed. This operation, besides allowing for maintenance of the detector underneath, is needed for making interventions that will reinforce the alignment measurements and make the operation of the alignment system more reliable. For that purpose and also for their general maintenance and recalibration, the alignment components will be transferred to the Alignment Lab situated in the ISR area. For the track-based alignment, attention is focused on the determination of systematic uncertainties, which have become dominant, since now there is a large statistics of muon tracks. This will allow for an improved Monte Carlo misalignment scenario and updated alignment position errors, crucial for high-momentum muon analysis such as Z′ searches.

  1. Alpine Pixel Detector Layout

    CERN Document Server

    Delebecque, P; The ATLAS collaboration; Geffroy, N; Massol, N; Rambure, T; Todorov, T

    2013-01-01

    A description of an optimized layout of pixel sensors based on a stave that combines both barrel and endcap module orientations. The mechanical stiffness of the structure is provided by carbon fiber shells spaced by carbon foam. The cooling of the modules is provided by two-phase $CO_{2}$ flowing in a thin titanium pipe glued inside the carbon fiber foam. The electrical services of all modules are provided by a single stave flex. This layout eliminates the need for separate barrel and endcap detector structures, and therefore the barrel services material in front of the endcap. The transition from barrel to endcap module orientation is optimized separately for each layer in order to minimize the active pixel area and the traversed material. The sparse module spacing in the endcap part of the stave allows for multiple fixation points, and for a stiff overall structure composed only of staves interconnected by stiff disks.

  2. The SPICE Detector at ISAC

    Directory of Open Access Journals (Sweden)

    Garnsworthy A.B.

    2013-12-01

    Full Text Available A new ancillary detector system for the TIGRESS HPGe array called SPectrometer for Internal Conversion Electrons (SPICE is currently under development. SPICE consists of a segmented electron detector, photon shield and a permanent magnetic lens. SPICE will enable in-beam electron spectroscopy and, in coupling to the TIGRESS HPGe array, coincident gamma-electron spectroscopy with stable and radioactive beams.

  3. Micro-channel plate detector

    Science.gov (United States)

    Elam, Jeffrey W.; Lee, Seon W.; Wang, Hsien -Hau; Pellin, Michael J.; Byrum, Karen; Frisch, Henry J.

    2015-09-22

    A method and system for providing a micro-channel plate detector. An anodized aluminum oxide membrane is provided and includes a plurality of nanopores which have an Al coating and a thin layer of an emissive oxide material responsive to incident radiation, thereby providing a plurality of radiation sensitive channels for the micro-channel plate detector.

  4. Micromegas detector developments for MIMAC

    CERN Document Server

    Ferrer-Ribas, E; Calvet, D; Colas, P; Druillole, F; Giomataris, Y; Iguaz, F J; Mols, J P; Pancin, J; Papaevangelou, T; Billard, J; Bosson, G; Bouly, J L; Bourrion, O; Fourel, Ch; Grignon, C; Guillaudin, O; Mayet, F; Richer, J P; Santos, D; Golabek, C; Lebreton, L

    2011-01-01

    The aim of the MIMAC project is to detect non-baryonic Dark Matter with a directional TPC. The recent Micromegas efforts towards building a large size detector will be described, in particular the characterization measurements of a prototype detector of 10 $\\times$ 10 cm$^2$ with a 2 dimensional readout plane. Track reconstruction with alpha particles will be shown.

  5. ALICE Time Of Flight Detector

    CERN Multimedia

    Alici, A

    2013-01-01

    Charged particles in the intermediate momentum range are identified in ALICE by the Time Of Flight (TOF) detector. The time measurement with the TOF, in conjunction with the momentum and track length measured by the tracking detector, is used to calculate the particle mass.

  6. R& D for Future Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Brau, J.

    2004-12-13

    Research and development of detector technology are critical to the future particle physics program. The goals of the International Linear Collider, in particular, require advances that are challenging, despite the progress driven in recent years by the needs of the Large Hadron Collider. The ILC detector goals and challenges are described and the program to address them is summarized.

  7. Fast Timing for Collider Detectors

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Advancements in fast timing particle detectors have opened up new possibilities to design collider detectors that fully reconstruct and separate event vertices and individual particles in the time domain. The applications of these techniques are considered for the physics at HL-LHC.

  8. Space-based detectors

    Science.gov (United States)

    Sesana, A.; Weber, W. J.; Killow, C. J.; Perreur-Lloyd, M.; Robertson, D. I.; Ward, H.; Fitzsimons, E. D.; Bryant, J.; Cruise, A. M.; Dixon, G.; Hoyland, D.; Smith, D.; Bogenstahl, J.; McNamara, P. W.; Gerndt, R.; Flatscher, R.; Hechenblaikner, G.; Hewitson, M.; Gerberding, O.; Barke, S.; Brause, N.; Bykov, I.; Danzmann, K.; Enggaard, A.; Gianolio, A.; Vendt Hansen, T.; Heinzel, G.; Hornstrup, A.; Jennrich, O.; Kullmann, J.; Møller-Pedersen, S.; Rasmussen, T.; Reiche, J.; Sodnik, Z.; Suess, M.; Armano, M.; Sumner, T.; Bender, P. L.; Akutsu, T.; Sathyaprakash, B. S.

    2014-12-01

    The parallel session C5 on Space-Based Detectors gave a broad overview over the planned space missions related to gravitational wave detection. Overviews of the revolutionary science to be expected from LISA was given by Alberto Sesana and Sasha Buchman. The launch of LISA Pathfinder (LPF) is planned for 2015. This mission and its payload "LISA Technology Package" will demonstrate key technologies for LISA. In this context, reference masses in free fall for LISA, and gravitational physics in general, was described by William Weber, laser interferometry at the pico-metre level and the optical bench of LPF was presented by Christian Killow and the performance of the LPF optical metrology system by Paul McNamara. While LPF will not yet be sensitive to gravitational waves, it may nevertheless be used to explore fundamental physics questions, which was discussed by Michele Armano. Some parts of the LISA technology that are not going to be demonstrated by LPF, but under intensive development at the moment, were presented by Oliver Jennrich and Oliver Gerberding. Looking into the future, Japan is studying the design of a mid-frequency detector called DECIGO, which was discussed by Tomotada Akutsu. Using atom interferometry for gravitational wave detection has also been recently proposed, and it was critically reviewed by Peter Bender. In the nearer future, the launch of GRACE Follow-On (for Earth gravity observation) is scheduled for 2017, and it will include a Laser Ranging Interferometer as technology demonstrator. This will be the first inter-spacecraft laser interferometer and has many aspects in common with the LISA long arm, as discussed by Andrew Sutton.

  9. Spatio-energetic cross-talks in photon counting detectors: detector model and correlated Poisson data generator

    Science.gov (United States)

    Taguchi, Katsuyuki; Polster, Christoph; Lee, Okkyun; Kappler, Steffen

    2016-03-01

    An x-ray photon interacts with photon counting detectors (PCDs) and generates an electron charge cloud or multiple clouds. The clouds (thus, the photon energy) may be split between two adjacent PCD pixels when the interaction occurs near pixel boundaries, producing a count at both of the two pixels. This is called double-counting with charge sharing. The output of individual PCD pixel is Poisson distributed integer counts; however, the outputs of adjacent pixels are correlated due to double-counting. Major problems are the lack of detector noise model for the spatio-energetic crosstalk and the lack of an efficient simulation tool. Monte Carlo simulation can accurately simulate these phenomena and produce noisy data; however, it is not computationally efficient. In this study, we developed a new detector model and implemented into an efficient software simulator which uses a Poisson random number generator to produce correlated noisy integer counts. The detector model takes the following effects into account effects: (1) detection efficiency and incomplete charge collection; (2) photoelectric effect with total absorption; (3) photoelectric effect with fluorescence x-ray emission and re-absorption; (4) photoelectric effect with fluorescence x-ray emission which leaves PCD completely; and (5) electric noise. The model produced total detector spectrum similar to previous MC simulation data. The model can be used to predict spectrum and correlation with various different settings. The simulated noisy data demonstrated the expected performance: (a) data were integers; (b) the mean and covariance matrix was close to the target values; (c) noisy data generation was very efficient

  10. Response function of semiconductor detectors, Ge and Si(Li); Funcao resposta de detectores semicondutores, Ge e Si(Li)

    Energy Technology Data Exchange (ETDEWEB)

    Zevallos Chavez, Juan Yury

    2003-07-01

    The Response Function (RF) for Ge and Si(Li) semiconductor detectors was obtained. The RF was calculated for five detectors, four Hp Ge with active volumes of 89 cm{sup 3} , 50 cm{sup 3} , 8 cm{sup 3} and 5 cm{sup 3}, and one Si(Li) with 0.143 cm{sup 3} of active volume. The interval of energy studied ranged from 6 keV up to 1.5 MeV. Two kinds of studies were done in this work. The first one was the RF dependence with the detection geometry. Here the calculation of the RF for a geometry named as simple and an extrapolation of that RF, were both done. The extrapolation process analyzed both, spectra obtained with a shielding geometry and spectra where the source-detector distance was modified. The second one was the RF dependence with the detection electronics. This study was done varying the shaping time of the pulse in the detection electronics. The purpose was to verify the effect of the ballistic deficit in the resolution of the detector. This effect was not observed. The RF components that describe the region of the total absorption of the energy of the incident photons, and the partial absorption of this energy, were both treated. In particular, empirical functions were proposed for the treatment of both, the multiple scattering originated in the detector (crystal), and the photon scattering originated in materials of the neighborhood of the crystal. Another study involving Monte Carlo simulations was also done in order to comprehend the photon scattering structures produced in an iron shield. A deconvolution method is suggested, for spectra related to scattered radiation in order to assess the dose delivered to the scatterer. (author)

  11. ENSTAR detector for -mesic studies

    Indian Academy of Sciences (India)

    A Chatterjee; B J Roy; V Jha; P Shukla; H Machnder; GEM Collaboration

    2006-05-01

    We have initiated a search for a new type of nuclear matter, the -mesic nucleus, using beams from the multi-GeV hadron facility, COSY at Juelich, Germany. A large acceptance scintillator detector, ENSTAR has been designed and built at BARC, Mumbai and fully assembled and tested at COSY. A test run for calibration and evaluation has been completed. In this contribution we present the design and technical details of the ENSTAR detector and how it will be used to detect protons and pions (the decay products of -mesic bound state). The detector is made of plastic scintillators arranged in three concentric cylindrical layers. The readout of the detectors is by means of optical fibres. The layers are used to generate - spectra for particle identification and total energy information of stopped particles. The granularity of the detector allows for position ( and ) determination making the event reconstruction kinematically complete.

  12. Processing and characterization of epitaxial GaAs radiation detectors

    CERN Document Server

    Wu, X; Arsenovich, T; Gädda, A; Härkönen, J; Junkes, A; Karadzhinova, A; Kostamo, P; Lipsanen, H; Luukka, P; Mattila, M; Nenonen, S; Riekkinen, T; Tuominen, E; Winkler, A

    2015-01-01

    GaAs devices have relatively high atomic numbers (Z=31, 33) and thus extend the X-ray absorption edge beyond that of Si (Z=14) devices. In this study, radiation detectors were processed on GaAs substrates with 110 $\\mu\\textrm{m}$ - 130 $\\mu\\textrm{m}$ thick epitaxial absorption volume. Thick undoped and heavily doped p$^+$ epitaxial layers were grown using a custom-made horizontal Chloride Vapor Phase Epitaxy (CVPE) reactor, the growth rate of which was about 10 $\\mu\\textrm{m}$/h. The GaAs p$^+$/i/n$^+$ detectors were characterized by Capacitance Voltage ($CV$), Current Voltage ($IV$), Transient Current Technique (TCT) and Deep Level Transient Spectroscopy (DLTS) measurements. The full depletion voltage ($V_{\\textrm{fd}}$) of the detectors with 110 $\\mu\\textrm{m}$ epi-layer thickness is in the range of 8 V - 15 V and the leakage current density is about 10 nA/cm$^2$. The signal transit time determined by TCT is about 5 ns when the bias voltage is well above the value that produces the peak saturation drift ve...

  13. Recent detector developments at SINTEF (industrial presentation)

    Science.gov (United States)

    Sundby Avset, Berit; Evensen, Lars; Uri Jensen, Geir; Mo, Sjur; Kari Schjølberg-Henriksen; Westgaard, Trond

    1998-02-01

    Results from SINTEF's research on radiation hardness of silicon detectors, thin silicon detectors, silicon drift devices, reach-through avalanche photodiodes, and detectors with thin dead layers are presented.

  14. The 150 ns detector project: Progress with small detectors

    Science.gov (United States)

    Warburton, W. K.; Russell, S. R.; Kleinfelder, Stuart A.; Segal, Julie

    1994-09-01

    This project's long term goal is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1 × 256 1D and 8 × 8 2D detectors, 256 × 256 2D detectors and, finally, 1024 × 1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front end preamplifiers are being integrated first, since their design and performance are both the most unusual and also critical to the project's success. Similarly, our early work is also concentrating on devising and perfecting detector structures which are thick enough (1 mm) to absorb over 99% of the incident X-rays in the energy range of interest. In this paper we discuss our progress toward the 1 × 256 1D and 8 × 8 2D detectors. We have fabricated sample detectors at Stanford's Center for Integrated Systems and are preparing both to test them individually and to wirebond them to the preamplifier samples to produce our first working small 1D and 2D detectors. We will describe our solutions to the design problems associated with collecting charge in less than 30 ns from 1 mm thick pixels in high resistivity silicon. We have constructed and tested the front end of our preamplifier design using a commercial 1.2 μm CMOS technology and are moving on to produce a few channels of the complete preamplifier, including a switchable gain stage and output stage. We will discuss both the preamplifier design and our initial test results.

  15. Acquisition System and Detector Interface for Power Pulsed Detectors

    Science.gov (United States)

    Cornat, Rémi; CALICE Colaboration

    A common DAQ system is being developed within the CALICE collaboration. It provides a flexible and scalable architecture based on giga-ethernet and 8b/10b serial links in order to transmit either slow control data, fast signals or read out data. A detector interface (DIF) is used to connect detectors to the DAQ system based on a single firmware shared among the collaboration but targeted on various physical implementations. The DIF allows to build, store and queue packets of data as well as to control the detectors providing USB and serial link connectivity. The overall architecture is foreseen to manage several hundreds of thousands channels.

  16. Acquisition System and Detector Interface for Power Pulsed Detectors

    CERN Document Server

    Cornat, R

    2012-01-01

    A common DAQ system is being developed within the CALICE collaboration. It provides a flexible and scalable architecture based on giga-ethernet and 8b/10b serial links in order to transmit either slow control data, fast signals or read out data. A detector interface (DIF) is used to connect detectors to the DAQ system based on a single firmware shared among the collaboration but targeted on various physical implementations. The DIF allows to build, store and queue packets of data as well as to control the detectors providing USB and serial link connectivity. The overall architecture is foreseen to manage several hundreds of thousands channels.

  17. Multifunctional hybrids for electromagnetic absorption

    Energy Technology Data Exchange (ETDEWEB)

    Huynen, I. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Quievy, N. [Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bailly, C. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bollen, P. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Detrembleur, C. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium); Eggermont, S.; Molenberg, I. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Thomassin, J.M.; Urbanczyk, L. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium)

    2011-05-15

    Highlights: > EM absorption requires low dielectric constant and {approx}1 S/m electrical conductivity. > New hybrids were processed with CNT-filled polymer foam inserted in Al honeycomb. > The EM absorption in the GHz range is superior to any known material. > A closed form model is used to guide the design of the hybrid. > The architectured material is light with potential for thermal management. - Abstract: Electromagnetic (EM) interferences are ubiquitous in modern technologies and impact on the reliability of electronic devices and on living cells. Shielding by EM absorption, which is preferable over reflection in certain instances, requires combining a low dielectric constant with high electrical conductivity, which are antagonist properties in the world of materials. A novel class of hybrid materials for EM absorption in the gigahertz range has been developed based on a hierarchical architecture involving a metallic honeycomb filled with a carbon nanotube-reinforced polymer foam. The waveguide characteristics of the honeycomb combined with the performance of the foam lead to unexpectedly large EM power absorption over a wide frequency range, superior to any known material. The peak absorption frequency can be tuned by varying the shape of the honeycomb unit cell. A closed form model of the EM reflection and absorption provides a tool for the optimization of the hybrid. This designed material sets the stage for a new class of sandwich panels combining high EM absorption with mass efficiency, stiffness and thermal management.

  18. Water absorption in brick masonry

    NARCIS (Netherlands)

    Brocken, H.J.P.; Smolders, H.R.

    1996-01-01

    The water absorption in brick, mortar that was cured separately, and masonry samples was studied using NMR. Models of the moisture transport are usually formulated on the basis of a diffusion equation. In the case of water absorption in separate brick and mortar samples, the moisture diffusivity in

  19. Phytases for improved iron absorption

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Meyer, Anne S.

    2016-01-01

    Phytase enzymes present an alternative to iron supplements, because they have been shown to improve iron absorption by means of catalysing the degradation of a potent iron absorption inhibitor: phytic acid. Phytic acid is a hexaphosphate of inositol and is particularly prevalent in cereal grains...

  20. Detector instrumentation for nuclear fission studies

    Indian Academy of Sciences (India)

    Akhil Jhingan

    2015-09-01

    The study of heavy-ion-induced fusion–fission reactions require nuclear instrumentation that include particle detectors such as proportional counters, ionization chambers, silicon detectors, scintillation detectors, etc., and the front-end electronics for these detectors. Using the detectors mentioned above, experimental facilities have been developed for carrying out fusion–fission experiments. This paper reviews the development of detector instrumentation at IUAC.

  1. Experimental determination of the self-absorption factor for MTR plates by passive gamma spectrometric measurement

    Science.gov (United States)

    Berndt, R.; Mortreau, P.

    2011-07-01

    The measurement of the absolute activity or the mass of radioactive substances by gamma spectrometry needs to include a correction for the radiation absorption inside the source volume, the so-called self-absorption factor. It depends on geometry and material composition of the source, the detector geometry and on the geometrical arrangement of source and gamma radiation detector; it can be calculated if full information about all that is available. This article however describes how to determine the self-absorption factor from measurements if the radiation sources are plates of uranium fuel with typical parameters of nuclear fuel for MTR reactors and without using detail information on the source geometry, thus allowing easy inspection without relying on - potentially falsified - declarations on the internal properties of the fuel objects and without calculation.

  2. Light absorption of silicon nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Gondorf, Andreas; Meier, Cedrik; Luettjohann, Stephan; Offer, Matthias; Lorke, Axel [Experimental Physics, University of Duisburg-Essen (Germany); Wiggers, Hartmut [Combustion and Gas Dynamics, University of Duisburg-Essen (Germany)

    2007-07-01

    We have studied silicon nanoparticles fabricated by gas-phase condensation and in-flight sintering using absorption and photoluminescence (PL) spectroscopy. We observe a quantum size effect in PL as well as in absorption spectroscopy. From an analysis of the absorption spectra we are able to identify the character of the band gap of the nanoparticles as indirect. This result is supported by measurements of the decay time of the photoluminescence of excitons. The decay time is four orders of magnitude larger than in direct semiconductors. Moreover, we are able to observe the influence of the particle size distribution in the absorption spectra. The size distribution follows the lognormal distribution. In order to explain the surprisingly small dependence of the absorption edge on the mean particle diameter, we discuss a model which takes into acount the lognormal size distribution.

  3. Interband cascade detectors

    Science.gov (United States)

    Chuang, Shun Lien (Inventor); Li, Jian (Inventor); Yang, Rui Q. (Inventor)

    2007-01-01

    A device for detecting radiation, typically in the infrared. Photons are absorbed in an active region of a semiconductor device such that the absorption induces an interband electronic transition and generates photo-excited charge carriers. The charge carriers are coupled into a carrier transport region having multiple quantum wells and characterized by intersubband relaxation that provides rapid charge carrier collection. The photo-excited carriers are collected from the carrier transport region at a conducting contact region. Another carrier transport region characterized by interband tunneling for multiple stages draws charge carriers from another conducting contact and replenishes the charge carriers to the active region for photo-excitation. A photocurrent is generated between the conducting contacts through the active region of the device.

  4. Superconducting detector of IR single-photons based on thin WSi films

    CERN Document Server

    Seleznev, V A; Vakhtomin, Yu B; Morozov, P V; Zolotov, P I; Vasilev, D D; Moiseev, K M; Malevannaya, E I; Smirnov, K V

    2016-01-01

    We have developed the deposition technology of WSi thin films 4 to 9 nm thick with high temperature values of superconducting transition (Tc~4 K). Based on deposed films there were produced nanostructures with indicative planar sizes ~100 nm, and the research revealed that even on nanoscale the films possess of high critical temperature values of the superconducting transition (Tc~3.3-3.7K ) which certifies high quality and homogeneity of the films created. The first experiments on creating superconducting single-photon detectors showed that the detectors SDE (system detection efficiency) with increasing bias current (Ib) reaches a constant value of ~30% (for 1550 nm) defined by infrared radiation absorption by the superconducting structure. To enhance radiation absorption by the superconductor there were created detectors with cavity structures which demonstrated a practically constant value of quantum efficiency >65% for bias currents Ib>=0.6Ic. The minimal dark counts level (DC) made 1 s^-1 limited with ba...

  5. Plastic neutron detectors.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Tiffany M.S; King, Michael J.; Doty, F. Patrick

    2008-12-01

    This work demonstrated the feasibility and limitations of semiconducting {pi}-conjugated organic polymers for fast neutron detection via n-p elastic scattering. Charge collection in conjugated polymers in the family of substituted poly(p-phenylene vinylene)s (PPV) was evaluated using band-edge laser and proton beam ionization. These semiconducting materials can have high H/C ratio, wide bandgap, high resistivity and high dielectric strength, allowing high field operation with low leakage current and capacitance noise. The materials can also be solution cast, allowing possible low-cost radiation detector fabrication and scale-up. However, improvements in charge collection efficiency are necessary in order to achieve single particle detection with a reasonable sensitivity. The work examined processing variables, additives and environmental effects. Proton beam exposure was used to verify particle sensitivity and radiation hardness to a total exposure of approximately 1 MRAD. Conductivity exhibited sensitivity to temperature and humidity. The effects of molecular ordering were investigated in stretched films, and FTIR was used to quantify the order in films using the Hermans orientation function. The photoconductive response approximately doubled for stretch-aligned films with the stretch direction parallel to the electric field direction, when compared to as-cast films. The response was decreased when the stretch direction was orthogonal to the electric field. Stretch-aligned films also exhibited a significant sensitivity to the polarization of the laser excitation, whereas drop-cast films showed none, indicating improved mobility along the backbone, but poor {pi}-overlap in the orthogonal direction. Drop-cast composites of PPV with substituted fullerenes showed approximately a two order of magnitude increase in photoresponse, nearly independent of nanoparticle concentration. Interestingly, stretch-aligned composite films showed a substantial decrease in

  6. Application of two-photon absorption in PWO scintillator for fast timing of interaction with ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Auffray, E. [CERN, Geneva (Switzerland); Buganov, O. [Stepanov Institute of Physics, Minsk (Belarus); Korjik, M.; Fedorov, A. [Research Institute for Nuclear Problems, Belarus State University, 11 Bobruiskaya, 220030 Minsk (Belarus); Nargelas, S.; Tamulaitis, G. [Semiconductor Physics Department and Institute of Applied Research, Vilnius University, Saulėtekio 9-III, LT-10222 Vilnius (Lithuania); Tikhomirov, S. [Stepanov Institute of Physics, Minsk (Belarus); Vaitkevičius, A., E-mail: augustas.vaitkevicius@ff.vu.lt [Semiconductor Physics Department and Institute of Applied Research, Vilnius University, Saulėtekio 9-III, LT-10222 Vilnius (Lithuania)

    2015-12-21

    This work was aimed at searching for fast phenomena in scintillators in sub-10-ps range, a benchmark timing for the time response of radiation detectors in particle colliders. The pump-and-probe optical absorption technique with a tunable-wavelength parametric oscillator as the pump and a continuous-spectrum source as the probe beam was used to study lead tungstate PbWO{sub 4} (PWO) single crystals. It is shown that the rise time of the probe pulse absorption induced by the pump pulse is shorter than the pump pulse width of 200 fs. The approximately linear dependence of the probe absorption on the pump pulse energy density evidences that the induced absorption is caused by two-photon absorption involving one probe and one pump photon. We demonstrate that the intensity of the induced absorption at certain wavelengths is influenced by gamma irradiation, provided that an appropriate light polarization is selected. The application of the irradiation-sensitive nonlinearity for fast timing in radiation detectors is discussed. - Highlights: • Nonlinear transmittance with femtosecond rise time is observed in PWO scintillators. • The nonlinearity is caused by two-photon absorption of pump and probe photons. • Gamma irradiation imposes change in the nonlinearity for certain light polarization. • Application of the nonlinearity for fast timing in radiation detectors is feasible.

  7. Synchrotron study of charge transport in a CZT ring-drift detector

    Energy Technology Data Exchange (ETDEWEB)

    Hartog, Roland den, E-mail: r.h.den.hartog@sron.nl [High-Energy Astrophysics division of SRON, The Netherlands Institute of Space Research, Sorbonnelaan 2, 3584 CA, Utrecht (Netherlands); Owens, A., E-mail: aowens@rssd.esa.int [Science Projects Department of the European Space Agency, at ESTEC, P.O. Box 299, 2200 AG, Noordwijk (Netherlands); Kozorezov, A.G., E-mail: a.kozorezov@lancaster.ac.uk [Department of Physics of the University of Lancaster (United Kingdom); Wigmore, J.K. [Department of Physics of the University of Lancaster (United Kingdom); Gostilo, V., E-mail: office@bruker-baltic.lv [Bruker Baltic SAI, Ganibudambis 26, P.O. Box 33, Riga, LV-1005 (Latvia); Webb, M.A. [Hamburger Synchrotronstrahlungslabor HASYLAB at the Deutsches Elektronen-Synchrotron DESY, Notke-Strasse 85, D-22603, Hamburg (Germany)

    2011-08-21

    We report on experimental and theoretical results obtained with a CdZnTe (CZT) detector with a versatile read-out scheme: the ring detector. This detector has been tested extensively both in our laboratories and at the HASYLAB synchrotron facility and has demonstrated excellent energy resolution of up to 0.73%, over a wide dynamic range covering 6-662 keV. The key feature in this design is carefully managed charge transport, which eliminates the hole contribution, and optimizes the electron collection. We have developed a theoretical model of this detector, to enable the optimization of the read-out structure as a function of detector dimensions. A comparison between X-ray scans across the detector and model calculations shows that the model already captures all the major detector features, but still leaves a few challenging questions related to CZT surface conductivity. A defect in the detector, which breaks the expected cylindrical symmetry of the charge transport, is examined in detail by differential spectrometry, a powerful technique, which exploits differences in X-ray absorption between bulk and defect.

  8. Model-based optoacoustic inversion with arbitrary-shape detectors.

    Science.gov (United States)

    Rosenthal, Amir; Ntziachristos, Vasilis; Razansky, Daniel

    2011-07-01

    Optoacoustic imaging enables mapping the optical absorption of biological tissue using optical excitation and acoustic detection. Although most image-reconstruction algorithms are based on the assumption of a detector with an isotropic sensitivity, the geometry of the detector often leads to a response with spatially dependent magnitude and bandwidth. This effect may lead to attenuation or distortion in the recorded signal and, consequently, in the reconstructed image. Herein, an accurate numerical method for simulating the spatially dependent response of an arbitrary-shape acoustic transducer is presented. The method is based on an analytical solution obtained for a two-dimensional line detector. The calculated response is incorporated in the forward model matrix of an optoacoustic imaging setup using temporal convolution, and image reconstruction is performed by inverting the matrix relation. The method was numerically and experimentally demonstrated in two dimensions for both flat and focused transducers and compared to the spatial-convolution method. In forward simulations, the developed method did not suffer from the numerical errors exhibited by the spatial-convolution method. In reconstruction simulations and experiments, the use of both temporal-convolution and spatial-convolution methods lead to an enhancement in resolution compared to a reconstruction with a point detector model. However, because of its higher modeling accuracy, the temporal-convolution method achieved a noise figure approximated three times lower than the spatial-convolution method. The demonstrated performance of the spatial-convolution method shows it is a powerful tool for reducing reconstruction artifacts originating from the detector finite size and improving the quality of optoacoustic reconstructions. Furthermore, the method may be used for assessing new system designs. Specifically, detectors with nonstandard shapes may be investigated.

  9. ATLAS Forward Detectors and Physics

    CERN Document Server

    Soni, N

    2010-01-01

    In this communication I describe the ATLAS forward physics program and the detectors, LUCID, ZDC and ALFA that have been designed to meet this experimental challenge. In addition to their primary role in the determination of ATLAS luminosity these detectors - in conjunction with the main ATLAS detector - will be used to study soft QCD and diffractive physics in the initial low luminosity phase of ATLAS running. Finally, I will briefly describe the ATLAS Forward Proton (AFP) project that currently represents the future of the ATLAS forward physics program.

  10. Detector for a linear collider

    CERN Document Server

    Mnich, J

    2003-01-01

    The proposals under discussion for a new e^{+}e^{-} linear collider with centre-of-mass energies around 1 TeV include designs for large detectors with unprecedented performances in energy, momentum and position resolution. These very stringent requirements are dictated by the precision measurements aimed at this collider to complement the exploratory experiments at the Large Hadron Collider. Here a status report on detector R&D projects for the liner collider is given focused on the technologies under study for the vertex detector, the large tracking chamber and the calorimeters.

  11. Requirements on high resolution detectors

    Energy Technology Data Exchange (ETDEWEB)

    Koch, A. [European Synchrotron Radiation Facility, Grenoble (France)

    1997-02-01

    For a number of microtomography applications X-ray detectors with a spatial resolution of 1 {mu}m are required. This high spatial resolution will influence and degrade other parameters of secondary importance like detective quantum efficiency (DQE), dynamic range, linearity and frame rate. This note summarizes the most important arguments, for and against those detector systems which could be considered. This article discusses the mutual dependencies between the various figures which characterize a detector, and tries to give some ideas on how to proceed in order to improve present technology.

  12. CLIC Detector and Physics Status

    CERN Document Server

    AUTHOR|(SzGeCERN)627941

    2017-01-01

    This contribution to LCWS2016 presents recent developments within the CLICdp collaboration. An updated scenario for the staged operation of CLIC has been published; the accelerator will operate at 380 GeV, 1.5 TeV and 3 TeV. The lowest energy stage is optimised for precision Higgs and top physics, while the higher energy stages offer extended Higgs and BSM physics sensitivity. The detector models CLIC_SiD and CLIC_ILD have been replaced by a single optimised detector; CLICdet. Performance studies and R&D in technologies to meet the requirements for this detector design are ongoing.

  13. A computerized track detector reader

    Energy Technology Data Exchange (ETDEWEB)

    Rosinski, S.W. (Centralne Lab. Ochrony Radiologicznej, Warsaw (Poland))

    1993-01-01

    The structure and basic operation function of a computerized facility named Track Detection Reader is described. This facility is used for recording, counting and evaluation of defects made by [alpha]-particles in a solid state detector. It consists of a microscope equipped with the movable stage, a TV screen and PC-AT computer. The microscope stage is being controlled by a stepper motor. The TV screen enables surface visualization of the detector analyzed while the PC-AT computer is being used for digital analysis of the detector surface, according to the functions of the program. (author). 4 refs, 3 figs.

  14. The CDF Silicon Vertex Detector

    Energy Technology Data Exchange (ETDEWEB)

    Tkaczyk, S.; Carter, H.; Flaugher, B. [and others

    1993-09-01

    A silicon strip vertex detector was designed, constructed and commissioned at the CDF experiment at the Tevatron collider at Fermilab. The mechanical design of the detector, its cooling and monitoring are presented. The front end electronics employing a custom VLSI chip, the readout electronics and various components of the SVX system are described. The system performance and the experience with the operation of the detector in the radiation environment are discussed. The device has been taking colliding beams data since May of 1992, performing at its best design specifications and enhancing the physics program of CDF.

  15. Thermoluminescent Detectors in Mixed Fields

    CERN Document Server

    Mala, P; Biskup, B; Roeed, K

    2012-01-01

    This note reports on using of thermoluminescent detectors for radiation monitoring in the LHC tunnel and in the shielded areas around the tunnel. The accumulated annual doses in these areas vary a lot so a dosimeter used there should cover a large dose range. TL detectors can measure dose from 0.1 mGy to few kGy (with a recently proposed new technique which needs more studies up to 1 MGy). This report presents studies of these detectors in mixed fields similar to radiation field in the LHC and the possible usage of their results for calculation of high energy hadron and thermal neutron fluence.

  16. MUON DETECTORS: DT

    CERN Multimedia

    M. Dallavalle

    In the past months, the DT electronics has run in a stable and reliable way, demonstrated again through the CRAFT exercise. Operation when the CMS magnetic field was on has been satisfactory. The detector safety control and monitoring is improving constantly as the DT group accumulates running experience. The DT DAQ and DCS systems proved very stable during the intensive CRAFT period. The few issues that were identified by the DCS and on-line monitoring did not prevent the run to continue, so that the record of the DT in the data taking efficiency was very good. The long running period was also used to continue the transition from a system run by experts to one run by shifters, which was in the large part successful. Improvements, mostly in consolidation of error reporting, were identified and will be addressed in the coming shut-down. During the CRAFT data taking, DT triggered about 300 million cosmics with the magnet at 3.8T and the silicon strip tracker in the readout. Although a dedicated configuratio...

  17. MUON DETECTORS: CSC

    CERN Multimedia

    J. Hauser

    2011-01-01

    The CSC detector continued to operate well during the March-June 2011 period. As the luminosity has climbed three orders of magnitude, the currents drawn in the CSC high-voltage system have risen correspondingly, and the current trip thresholds have been increased from 1 μA to 5 μA (and 20 in ME1/1 chambers). A possible concern is that a long-lasting and undesirable corona is capable of drawing about 1 μA, and thus may not be detected by causing current trips; on the other hand it is easily dealt with by cycling HV when detected. To better handle coronas, software is being developed to better detect them, although a stumbling block is the instability of current measurements in some of the channels of the CAEN supplies used in ME1/1. A survey of other issues faced by the CSC Operations team was discussed at the 8th June 2011 CSC Operations/DPG meeting (Rakness). The most important issues, i.e. those that have caused a modest amount of downtime, are all being actively addressed. These are:...

  18. ATLAS Detector Upgrade Prospects

    CERN Document Server

    Dobre, Monica; The ATLAS collaboration

    2016-01-01

    After the successful operation at the centre-of-mass energies of 7 and 8 TeV in 2010-2012, the LHC is ramped up and successfully took data at the centre-of-mass energies of 13 TeV in 2015. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, delivering of the order of five times the LHC nominal instantaneous luminosity along with luminosity levelling. The ultimate goal is to extend the dataset from about few hundred f b −1 expected for LHC running to 3000 f b −1 by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of ext...

  19. MUON DETECTORS: RPC

    CERN Multimedia

    Pierluigi Paolucci

    2013-01-01

    In the second part of 2013 the two main activities of the RPC project are the reparation and maintenance of the present system and the construction and installation of the RE4 system. Since the opening of the barrel, repair activities on the gas, high-voltage and electronic systems are being done in parallel, in agreement with the CMS schedule. In YB0, the maintenance of the RPC detector was in the shadow of other interventions, nevertheless the scaffolding turned out to be a good solution for our gas leaks searches. Here we found eight leaking channels for about 100 l/h in total. 10 RPC/DT modules were partially extracted –– 90 cm –– in YB0, YB–1 and YB–2 to allow for the replacement of FE and LV distribution boards. Intervention was conducted on an additional two chambers on the positive endcap to solve LV and threshold control problems. Until now we were able to recover 0.67% of the total number of RPC electronic channels (1.5% of the channels...

  20. MUON DETECTORS: DT

    CERN Multimedia

    I. Redondo Fernandez

    2011-01-01

    The DT system has operated successfully during the entire 2011 data-taking: the fraction of good channels was always >99.4 % and the downtime caused to CMS amounts to a few inverse picobarns. This excellent performance does not come without a price: the DT group requested more than 30 short accesses to the underground experimental cavern (UXC).  A large fraction of interventions was for dealing with overheated LV Anderson connectors, whose failure can affect larger sections of the detector (a whole chamber, or half a wheel of the CMS barrel, etc.). A crash programme for reworking those connections will take place during the Year-End Technical Stop. The system of six vd chambers (VDC) that were installed on the DT exhaust gas line have operated successfully. The VDCs are small drift chambers the size of a shoebox that measure the drift velocity every 10 minutes. Possible deviations from the nominal value could be caused by a contamination of the gas mixture or changes in pressure or temperat...

  1. MUON DETECTORS: DT

    CERN Multimedia

    R.Carlin

    2010-01-01

    DT operation during 2010 LHC collisions, both in proton-proton and heavy ions, has been outstanding. The DT downtime has been below 0.1% throughout the whole year, mainly caused by the manual Resync commands that took around a minute for being processed. An automatic resynchronisation procedure has been enabled by August 27 and since then the downtime has been negligible (though constantly monitored). The need for these Resync commands is related to sporadic noise events that occasionally fill the RO buffers or unlock the readout links. Their rate is low, in the order of a few per week. Besides that, only one pp collisions run (1 hour 30 minutes run) has been marked as bad for DT, because of an incident with a temperature sensor that triggered a false alarm and powered off one wheel. Nevertheless, quite a large number of interventions (>30) have been made in the cavern during the year, in order to keep such a large fraction of the detector operational. Most of those are due to the overheating of the ...

  2. MUON DETECTORS: DT

    CERN Multimedia

    I. Redondo

    2011-01-01

    During the second quarter of 2011, the DT system has continued to operate successfully with a high fraction of good channels (>99 %) and causing extremely little downtime to CMS. The high fraction of operated channels did not come for free: DT requested 18 short UXC accesses in the 3 months from March to May 2011. The dominant causes for these interventions were HV related interventions (7), which typically affect a small fraction of a chamber, and interventions for dealing with overheated LV Anderson connectors (7), whose failure could affect larger fractions of the detector (a whole chamber, half a wheel). With respect to the CMS downtime, a successful effort with colleagues from the DT Track Finder of the Level-1 Trigger system allowed to overcome a relatively relevant source of downtime from DTTF FED Out-Of-Sync errors, which would appear randomly during data-taking. The DT group developed a system configuration that would make it possible to reproduce the error without beam, thereby sparing lumin...

  3. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    S. Szillasi

    2013-01-01

    The CMS detector has been gradually opened and whenever a wheel became exposed the first operation was the removal of the MABs, the sensor structures of the Hardware Barrel Alignment System. By the last days of June all 36 MABs have arrived at the Alignment Lab at the ISR where, as part of the Alignment Upgrade Project, they are refurbished with new Survey target holders. Their electronic checkout is on the way and finally they will be recalibrated. During LS1 the alignment system will be upgraded in order to allow more precise reconstruction of the MB4 chambers in Sector 10 and Sector 4. This requires new sensor components, so called MiniMABs (pictured below), that have already been assembled and calibrated. Image 6: Calibrated MiniMABs are ready for installation For the track-based alignment, the systematic uncertainties of the algorithm are under scrutiny: this study will enable the production of an improved Monte Carlo misalignment scenario and to update alignment position errors eventually, crucial...

  4. MUON DETECTORS: RPC

    CERN Multimedia

    G. Iaselli

    The RPC group has invested a large effort in the study of trigger spikes observed during CRAFT data taking. The chambers are susceptible to noise generated by the flickering of fluorescent and projector lamps in the cavern (with magnetic field on). Soon after the end of CRAFT, it was possible to reproduce the phenomena using a waveform generator and to study possible modifications to be implemented in the grounding schema. Hardware actions have been already taken in order to reduce the detector sensitivity: star washers on the chamber front panels and additional shielding have been added where possible. During the shutdown maintenance activity many different problems were tackled on the barrel part. A few faulty high voltage connector/cable problems were fixed; now only two RPC chambers are left with single-gap mode operation. One chamber in YB+2 was replaced due to gas leakage. All the front-end electronic boards were replaced in 3 chambers (stations MB2 and MB3 in YB-2), that had been damaged after the coo...

  5. Hybrid Superconducting Neutron Detectors

    CERN Document Server

    Merlo, V; Cirillo, M; Lucci, M; Ottaviani, I; Scherillo, A; Celentano, G; Pietropaolo, A

    2014-01-01

    A new neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction 10B+n $\\rightarrow$ $\\alpha$+ 7Li , with $\\alpha$ and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current Ic, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the supercond...

  6. MUON DETECTORS: CSC

    CERN Multimedia

    R. Breedon

    Figure 2: Five ME4/2 chambers mounted on the +endcap. At the end of June, five large, outer cathode strip chambers (CSC) that were produced as spares during the original production were mounted on part of the disk space reserved for ME4/2 on the positive endcap (Fig. 2). The chambers were cabled, attached to services, and fully integrated and commissioned into the CSC DAQ and trigger systems. Comprising almost a full trigger sector, CMS will be able to test the significant improvement the trigger efficiency of the EMU system that the presence of the full ME4/2 ring is expected to bring. The return of beam in November was observed as “splash” events in the CSCs in which the detectors were showered with a huge number of particles at the same time. Although the CSCs were operating at a lower standby voltage the multiple hits on a strips could not be individually distinguished.&am...

  7. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2012-01-01

      2011 data-taking was very satisfactory for both the RPC detector and trigger. The RPC system ran very smoothly in 2011, showing an excellent stability and very high data-tacking efficiency. Data loss for RPC was about 0.37%, corresponding to 19 pb−1. Most of the performance studies, based on 2011 data, are now completed and the results have been already approved by CMS to be presented at the RPC 2012 conference (February 2012 at LNF). During 2011, the number of disconnected chambers increased from six to eight corresponding to 0.8% of the full system, while the single-gap-mode chambers increased from 28 to 31. Most of the problematic chambers are due to bad high-voltage connection and electronic failures that can be solved only during the 2013-2014 Long Shutdown. 98.4% of the electronic channels were operational. The average detection efficiency in 2011 was about 95%, which was the same value measured during the HV scan done at the beginning of the 2011 data-taking. Efficiency has be...

  8. MUON DETECTORS: DT

    CERN Multimedia

    M. Dallavalle

    2013-01-01

    The DT collaboration is undertaking substantial work both for detector maintenance – after three years since the last access to the chambers and their front-end electronics – and upgrade. The most critical maintenance interventions are chambers and Minicrate repairs, which have not begun yet, because they need proper access to each wheel of the CMS barrel, meaning space for handling the big chambers in the few cases where they have to be extracted, and, more in general, free access from cables and thermal shields in the front and back side of the chambers. These interventions are planned for between the coming Autumn until next spring. Meanwhile, many other activities are happening, like the “pigtail” intervention on the CAEN AC/DC converters which has just taken place. The upgrade activities continue to evolve in good accordance with the schedule, both for the theta Trigger Board (TTRB) replacement and for the Sector Collector (SC) relocation from the UXC to the US...

  9. Commissioning a Hodoscope Detector

    Science.gov (United States)

    Lulis, Andrew; Merhi, Abdul; Frank, Nathan; Bazin, Daniel; Smith, Jenna; Thoennessen, Michael; MoNA Collaboration

    2013-10-01

    Experiments on neutron-rich nuclei are interesting since they test the limits of current nuclear theory. One method to populate neutron-rich nuclei is to utilize the (d,p) reaction in which the beam nucleus picks up a neutron from the target. This heavier nucleus immediately emits a neutron resulting in the same nucleus as the beam but with lower energy. One challenge is to discriminate decay products from unreacted beam particles by their difference in energy. A hodoscope was recently installed at the National Superconducting Cyclotron Laboratory (NSCL) as part of the MoNA-LISA-Sweeper setup to make experiments using a (d,p) reaction possible. The hodoscope is a 5 × 5 scintillator array consisting of CsI(Na) crystals with a resolution of better than 1%. This presentation will describe the recently commissioned detector and the results of the first data analysis using this device. Work supported by Augustana College and the National Science Foundation grant #0969173.

  10. MUON DETECTORS: RPC

    CERN Multimedia

    G. Pugliese

    2010-01-01

    In the second half of 2010 run, the overall behavior of the RPC system has been very satisfactory, both in terms of detector and trigger performance. This result was achieved through interventions by skilled personnel and fine-tuned analysis procedures. The hardware was quite stable: both gas and power systems did not present significant problems during the data-taking period, confirming the high reliability achieved. Only few interventions on some HV or LV channels were necessary during the periodical technical accesses. The overall result is given by the stable percentage of active channels at about 98.5%. The single exception was at beginning of the ion collisions, when it dipped to 97.4% because of the failure of one LV module, although this was recovered after a few days. The control and monitoring software is now more robust and efficient, providing prompt diagnostics on the status of the entire system. Significant efforts were made in collaboration with the CMS cooling team to secure proper working ...

  11. Transmission diamond imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Smedley, John, E-mail: smedley@bnl.gov; Pinelli, Don; Gaoweia, Mengjia [Brookhaven National Laboratory, Upton, NY (United States); Muller, Erik; Ding, Wenxiang; Zhou, Tianyi [Stony Brook University, Stony Brook, NY (United States); Bohon, Jen [Case Center for Synchrotron Biosciences, Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH (United States)

    2016-07-27

    Many modern synchrotron techniques are trending toward use of high flux beams and/or beams which require enhanced stability and precise understanding of beam position and intensity from the front end of the beamline all the way to the sample. For high flux beams, major challenges include heat load management in optics (including the vacuum windows) and a mechanism of real-time volumetric measurement of beam properties such as flux, position, and morphology. For beam stability in these environments, feedback from such measurements directly to control systems for optical elements or to sample positioning stages would be invaluable. To address these challenges, we are developing diamond-based instrumented vacuum windows with integrated volumetric x-ray intensity, beam profile and beam-position monitoring capabilities. A 50 µm thick single crystal diamond has been lithographically patterned to produce 60 µm pixels, creating a >1kilopixel free-standing transmission imaging detector. This device, coupled with a custom, FPGA-based readout, has been used to image both white and monochromatic x-ray beams and capture the last x-ray photons at the National Synchrotron Light Source (NSLS). This technology will form the basis for the instrumented end-station window of the x-ray footprinting beamline (XFP) at NSLS-II.

  12. MUON DETECTORS: RPC

    CERN Multimedia

    G. Iaselli

    2010-01-01

    During the technical stop, the RPC team was part of the CMS task force team working on bushing replacements in the Endcap cooling system, also validating the repairs in terms of connectivity (HV, LV and signal cables), and gas leak, on RE chambers. In parallel, the RPC team profited from the opportunity to cure several known problems: six chambers with HV problems (1 off + 5 single gaps) were recovered on both gaps; four known HV problems were localized at chamber level; additional temperature sensors were installed on cooling pipes on negative REs; one broken LV module in RE-1 was replaced. During the last month, the RPC group has made big improvements in the operations tools. New trigger supervisor software has substantially reduced the configuration time. Monitoring is now more robust and more efficient in providing prompt diagnostics. The detector has been under central DCS control for two weeks. Improvements have been made to both functionality and documentation and no major problems were found. Beam s...

  13. MUON DETECTORS: DT

    CERN Multimedia

    C. Fernandez Bedova and M. Dallavalle

    2010-01-01

    After successful operation during the 2009 LHC run, a number of fixes and improvements were carried out on the DT system the winter shutdown. The main concern was related with the impact of the extensive water leak that happened in October in YE+1. Opening of CMS end-caps allowed the DT crew to check if any Minicrates (containing the first level of readout and trigger electronics) in YB+2 and YB-2 were flooded with water. The affected region from top sectors in YB+2 reaches down to the bottom sectors in YB-2 following the water path in the barrel from end to end. No evidence of water penetration was observed, though the passage of water left oxidation and white streaks on the iron and components. In particular, large signs of oxidation have been seen on the YB-2 MB1 top and bottom stations. Review of the impact in YB+1 remains for future openings of CMS wheels, and at present, effort is focused on setting up the water leak detection system in the detector. Another important issue during this shutd...

  14. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2013-01-01

    During LS1, the Resistive Plate Chamber (RPC) collaboration is focusing its efforts on installation and commissioning of the fourth endcap station (RE4) and on the reparation and maintenance of the present system (1100 detectors). The 600 bakelite gaps, needed to build 200 double-gap RE4 chambers are being produced in Korea. Chamber construction and testing sites are located at CERN, in Ghent University, and at BARC (India). At present, 42 chambers have been assembled, 32 chambers have been successfully tested with cosmic rays runs and 7 Super Modules, made by two chambers, have been built at CERN by a Bulgarian/Georgian/Italian team and are now ready to be installed in the positive endcap. The 36 Super Modules needed to complete the positive endcap will be ready in September and installation is scheduled for October 2013. The Link-Board system for RE4 is under construction in Naples. Half of the system has been delivered at CERN in June. Six crates (Link-Board Boxes) and 75 boards, needed to instrument t...

  15. MUON DETECTORS: DT

    CERN Multimedia

    C. Fernandez Bedoya

    2012-01-01

      The major activity of the DT group during this Year-End Technical Stop has been the reworking of LV modules. It has been a large campaign, carefully planned, to try to solve, once and for all, the long-standing problem of Anderson Power connectors overheating. The solution involved removing the 140 CAEN modules from the detector (6.5 kg each), soldering of “pigtails” in a temporary workshop in USC, and thorough testing of all the modules in a local system installed in USC. The operation has been satisfactorily smooth, taking into account the magnitude of the intervention. The system is now back in good shape and ready for commissioning. In addition, HV boards have been cleaned up, HV USC racks have been equipped with water detection cables, and the gas and HV have been switched back on smoothly. Other significant activities have also taken place during this YETS, such as the installation of a new and faster board for the Minicrates secondary link and the migration to Scienti...

  16. ATLAS Detector Upgrade Prospects

    CERN Document Server

    Dobre, Monica; The ATLAS collaboration

    2016-01-01

    After the successful operation at the center-of-mass energies of 7 and 8 TeV in 2010 - 2012, the LHC is ramped up and successfully took data at the center-of-mass energies of 13 TeV in 2015. Meanwhile, plans are actively advancing for a series of upgrades of the accelerator, culminating roughly ten years from now in the high-luminosity LHC (HL-LHC) project, delivering of the order of five times the LHC nominal instantaneous luminosity along with luminosity leveling. The ultimate goal is to extend the dataset from about few hundred fb−1 expected for LHC running to 3000 fb−1 by around 2035 for ATLAS and CMS. The challenge of coping with the HL-LHC instantaneous and integrated luminosity, along with the associated radiation levels, requires further major changes to the ATLAS detector. The designs are developing rapidly for a new all-silicon tracker, significant upgrades of the calorimeter and muon systems, as well as improved triggers and data acquisition. ATLAS is also examining potential benefits of extens...

  17. Method and apparatus for enhancing laser absorption sensitivity

    Science.gov (United States)

    Webster, Christopher R. (Inventor)

    1987-01-01

    A simple optomechanical method and apparatus is described for substantially reducing the amplitude of unwanted multiple interference fringes which often limit the sensitivities of tunable laser absorption spectrometers. An exterior cavity is defined by partially transmissible surfaces such as a laser exit plate, a detector input, etc. That cavity is spoiled by placing an oscillating plate in the laser beam. For tunable diode laser spectroscopy in the mid-infrared region, a Brewster-plate spoiler allows the harmonic detection of absorptances of less than 10 to the -5 in a single laser scan. Improved operation is achieved without subtraction techniques, without complex laser frequency modulation, and without distortion of the molecular lineshape signal. The technique is applicable to tunable lasers operating from UV to IR wavelengths and in spectrometers which employ either short or long pathlengths, including the use of retroreflectors or multipass cells.

  18. Absorption spectroscopy of RDX monopropellant flames: CN and NH concentrations

    Science.gov (United States)

    Homan, B. E.; Vanderhoff, John A.

    1997-11-01

    UV-visible multi-channel absorption spectroscopy has been used to probe the self-sustained combustion of pressed RDX, a main energetic ingredient found in modern day propellants and explosives. The two dimensional feature of an intensified CCD detector allowed simultaneous recording of multiple, spatially distinct absorption spectra. Between 10 and 12 equally spaced absorption spectra with spatial resolution as small as 0.163 mm have been obtained during 1 ms exposure. The number of absorption spectra and the spatial resolution can easily be set by the detector software, size of the excitation sheet and the focal length of the collection lens. Temporal resolution in the UV region has been increased to 1 ms by pulsing the light source. A 0.54 joule pulse with a duration of 0.75 ms was added to a simmering Xenon arc lamp for the measurement of combustion species. The increase in light intensity of 30 and 70 times the non-pulsed output provided the necessary light flux to achieve single pulse, multiple absorption spectra. To increase the species concentration sensitivity of the experiment, a triple pass optical arrangement was adopted. Partially silvered windows were installed at an angle to the beam providing for three passes across the samples. The corresponding path length was increased by a factor of 2.8 times the sample diameter. Least squares analysis of absorption spectra provide mole fraction profiles for OH, CN and NH along with temperature. Profiles for NC and HN have been determined for self-sustained combustion of RDX in 1.0, 1.5 and 2.0 atm air. Peak CN mole fractions of about 200 ppm are observed at 1 atm pressure and the NH mole fraction is about a factor of two lower. As the pressure is increased the reactive CN and HN species peak closer to the combusting surface and reside over a smaller spatial extent. Peak concentrations drop for these higher pressures, but may be due, at least in part, to limitations of the spatial resolution of the absorption

  19. Gastrointestinal citrate absorption in nephrolithiasis

    Science.gov (United States)

    Fegan, J.; Khan, R.; Poindexter, J.; Pak, C. Y.

    1992-01-01

    Gastrointestinal absorption of citrate was measured in stone patients with idiopathic hypocitraturia to determine if citrate malabsorption could account for low urinary citrate. Citrate absorption was measured directly from recovery of orally administered potassium citrate (40 mEq.) in the intestinal lavage fluid, using an intestinal washout technique. In 7 stone patients citrate absorption, serum citrate levels, peak citrate concentration in serum and area under the curve were not significantly different from those of 7 normal subjects. Citrate absorption was rapid and efficient in both groups, with 96 to 98% absorbed within 3 hours. The absorption of citrate was less efficient from a tablet preparation of potassium citrate than from a liquid preparation, probably due to a delayed release of citrate from wax matrix. However, citrate absorption from solid potassium citrate was still high at 91%, compared to 98% for a liquid preparation. Thus, hypocitraturia is unlikely to be due to an impaired gastrointestinal absorption of citrate in stone patients without overt bowel disease.

  20. Spectral phase-contrast CT using the LAMBDA detector

    Energy Technology Data Exchange (ETDEWEB)

    Ehn, Sebastian; Epple, Michael; Potdevin, Guillaume; Renker, Dieter; Pfeiffer, Franz [Chair of Biomedical Physics, TU Muenchen (Germany); Pennicard, David; Smoljanin, Sergej; Lange, Sabine; Graafsma, Heinz [DESY, Hamburg (Germany)

    2013-07-01

    X-ray phase-contrast techniques offer significantly improved soft-tissue contrast compared to absorption-based measurements commonly used in clinical radiology. Grating-based phase contrast methods have proven to be fully compatible to standard laboratory X-ray sources and are currently being used in preclinical research. However, the imaging quality in this method is strongly energy-dependent, which may result in poor signal to noise ratios when using beams with broad energy spectra. One can overcome this disadvantage using energy sensitive detectors like the Medipix3, only taking into account the energies where the SNR is at a maximum. Thereby, an improvement to image quality and a reduction in radiation dose may be reached. This presentation will give an overview over the new Medipix3-based LAMBDA detector, which is currently being developed at DESY, used in grating-based spectral phase-contrast tomography.

  1. Superconducting tunnel junction detectors for soft x-ray astrophysics

    Science.gov (United States)

    Verhoeve, P.; Hijmering, R. A.; Martin, D. D. E.; Jerjen, I.; Peacock, A.; Venn, R.

    2006-06-01

    The requirement on energy resolution for detectors in future X-ray satelite missions such as XEUS (X-ray Evolving Universe Spectroscopy mission) is 80%. In addition, the requirements for field of view and angular resolution demand a detector array of typically 150x150 micron sized pixels in a 30x30 pixel format. DROIDs (Distributed Read Out Imaging Devices), consisting of a superconducting absorber strip with superconducting tunnel junctions (STJs) as read-out devices on either end, can fulfill these requirements. The amplitudes of the two signals from the STJs provide information on the absorption position and the energy of the incoming photon in the absorber. In this paper we present the development status of Ta/Al 1-D DROIDs, as well as the the short term development program that should result in a full size XEUS array.

  2. A Rapid Coliform Detector Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC, in collaboration with Lucigen, proposes a rapid genetic detector for spaceflight water systems to enable real-time detection of E-coli with minimal...

  3. Detector Fundamentals for Reachback Analysts

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Myers, Steven Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-03

    This presentation is a part of the DHS LSS spectroscopy course and provides an overview of the following concepts: detector system components, intrinsic and absolute efficiency, resolution and linearity, and operational issues and limits.

  4. Rapid Multiplex Microbial Detector Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC, in collaboration with Lucigen, proposes a rapid nucleic acid-based detector for spaceflight water systems to enable simultaneous quantification of multiple...

  5. Belle II Silicon Vertex Detector

    CERN Document Server

    Mohanty, Gagan B

    2015-01-01

    The Belle II experiment at the SuperKEKB collider in Japan is designed to indirectly probe new physics using approximately 50 times the data recorded by its predecessor. An accurate determination of the decay-point position of subatomic particles such as beauty and charm hadrons as well as a precise measurement of low-momentum charged particles will play a key role in this pursuit. These will be accomplished by a vertex detector, which comprises two layers of pixelated silicon detector and four layers of silicon vertex detector. We describe herein the design, prototyping and construction efforts of the Belle-II silicon vertex detector that is aimed to be commissioned towards the middle of 2017.

  6. GEM Detector Electric Field Simulation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    GEM (Gas Electron Multiplier) detectors have been widely employed in the experimental field of high energy physics and nuclear physics. As a successor to drift chambers, GEMs are much easier to fabricate and have a much higher spatial resolution

  7. Silicon Drift Detectors for ALICE

    CERN Document Server

    Navach, F; CERN. Geneva

    1992-01-01

    The Silicon Drift Detector (SDD) is a semiconductor, not yet extensively used in HEP experiment, which has an excellent spatial resolution and granularity about comparable to a pixel device requiring a number of readout channels two order of magnitude less.

  8. Detector Description Framework in LHCb

    CERN Document Server

    Ponce, Sébastien

    2003-01-01

    The Gaudi architecture and framework are designed to provide a common infrastructure and environment for simulation, filtering, reconstruction and analysis applications. In this context, a Detector Description Service was developed in LHCb in order to also provide easy and coherent access to the description of the experimental apparatus. This service centralizes every information about the detector, including geometry, materials, alignment, calibration, structure and controls. From the proof of concept given by the first functional implementation of this service late 2000, the Detector Description Service has grown and has become one of the major components of the LHCb software, shared among all applications, including simulation, reconstruction, analysis and visualization. We describe here the full and functional implementation of the service. We stress the easiness of customization and extension of the detector description by the user, on the seamless integration with condition databases in order to handle ...

  9. Simple dynamic electromagnetic radiation detector

    Science.gov (United States)

    Been, J. F.

    1972-01-01

    Detector monitors gamma dose rate at particular position in a radiation facility where a mixed neutron-gamma environment exists, thus determining reactor power level changes. Device also maps gamma intensity profile across a neutron-gamma beam.

  10. Microscopic Simulation of Particle Detectors

    CERN Document Server

    Schindler, Heinrich

    Detailed computer simulations are indispensable tools for the development and optimization of modern particle detectors. The interaction of particles with the sensitive medium, giving rise to ionization or excitation of atoms, is stochastic by its nature. The transport of the resulting photons and charge carriers, which eventually generate the observed signal, is also subject to statistical fluctuations. Together with the readout electronics, these processes - which are ultimately governed by the atomic cross-sections for the respective interactions - pose a fundamental limit to the achievable detector performance. Conventional methods for calculating electron drift lines based on macroscopic transport coefficients used to provide an adequate description for traditional gas-based particle detectors such as wire chambers. However, they are not suitable for small-scale devices such as micropattern gas detectors, which have significantly gained importance in recent years. In this thesis, a novel approach, bas...

  11. Nanopillar Optical Antenna Avalanche Detectors

    Science.gov (United States)

    2014-08-30

    68 , (11), 10. 51. Adachi, S., Properties of aluminium gallium ...bandwidth products > 100 GHz. 2 UNIVERSITY OF CALIFORNIA Los Angeles Nanopillar Optical Antenna Avalanche Detectors A dissertation... products > 100 GHz. 6 iii The dissertation of Pradeep

  12. A Classification Leveraged Object Detector

    OpenAIRE

    Sun, Miao; Han, Tony X.; He, Zhihai

    2016-01-01

    Currently, the state-of-the-art image classification algorithms outperform the best available object detector by a big margin in terms of average precision. We, therefore, propose a simple yet principled approach that allows us to leverage object detection through image classification on supporting regions specified by a preliminary object detector. Using a simple bag-of- words model based image classification algorithm, we leveraged the performance of the deformable model objector from 35.9%...

  13. Surface events in HPGe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Abt, Iris; Dinter, Sabine; Faulstich, Florian; Majorovits, Bela; Stelzer, Franz [Max-Planck-Institut fuer Physik, Munich (Germany)

    2011-07-01

    Events on or close to the surface of high purity germanium, HPGe, detectors can introduce backgrounds in low background applications of such devices. The Galatea test-stand, especially developed and constructed at the MPI fuer Physik allows an almost full surface scan of a detector with alpha and beta sources. Events induced by alpha and beta particles can be characterized and surface effects can be studied. First comparisons between data and Monte Carlo are presented.

  14. Repeatability of Harris Corner Detector

    Institute of Scientific and Technical Information of China (English)

    HU Lili

    2003-01-01

    Interest point detectors are commonly employed to reduce the amount of data to be processed. The ideal interest point detector would robustly select those features which are most appropriate or salient for the application and data at hand. This paper shows that interest points are geometrically stable under different transformations.This property makes interest points very successful in the context of image matching. To measure this property quantatively, we introduce a evaluation criterion: repeatability rate.

  15. Electronic detectors for electron microscopy.

    Science.gov (United States)

    Faruqi, A R; McMullan, G

    2011-08-01

    Electron microscopy (EM) is an important tool for high-resolution structure determination in applications ranging from condensed matter to biology. Electronic detectors are now used in most applications in EM as they offer convenience and immediate feedback that is not possible with film or image plates. The earliest forms of electronic detector used routinely in transmission electron microscopy (TEM) were charge coupled devices (CCDs) and for many applications these remain perfectly adequate. There are however applications, such as the study of radiation-sensitive biological samples, where film is still used and improved detectors would be of great value. The emphasis in this review is therefore on detectors for use in such applications. Two of the most promising candidates for improved detection are: monolithic active pixel sensors (MAPS) and hybrid pixel detectors (of which Medipix2 was chosen for this study). From the studies described in this review, a back-thinned MAPS detector appears well suited to replace film in for the study of radiation-sensitive samples at 300 keV, while Medipix2 is suited to use at lower energies and especially in situations with very low count rates. The performance of a detector depends on the energy of electrons to be recorded, which in turn is dependent on the application it is being used for; results are described for a wide range of electron energies ranging from 40 to 300 keV. The basic properties of detectors are discussed in terms of their modulation transfer function (MTF) and detective quantum efficiency (DQE) as a function of spatial frequency.

  16. Instrumentation of the fast detector

    CERN Document Server

    Barczyk, A.; Malgeri, L.; Casella, C.; Pohl, M.; Deiters, K.; Dick, P.; Berdugo, J.; Casaus, J.; Mana, C.; Marin, J.; Martinez, G.; Sanchez, E.; Willmott, C.

    2008-01-01

    The Fiber Active Scintillator Target (FAST) is an imaging particle detector intended for high precision muon lifetime measurement. This measurement will lead to a determination of the Fermi coupling constant (GF) with an uncertainty of 1 ppm, one order of magnitude better than the current world average. This contribution presents a description of the detector instrumentation and the first results, which have validated the design of the system.

  17. The SELEX Phototube RICH Detector

    CERN Document Server

    Engelfried, J; Kilmer, J; Kozhevnikov, A P; Kubarovskii, V P; Molchanov, V V; Nemitkin, A V; Ramberg, E; Rud, V I; Stutte, L

    1999-01-01

    In this article, construction, operation, and performance of the RICH detector of Fermilab experiment 781 (SELEX) are described. The detector utilizes a matrix of 2848 phototubes for the photocathode to detect Cherenkov photons generated in a 10m Neon radiator. For the central region an N0 of 104/cm, corresponding to 13.6 hits on a beta=1 ring, was obtained. The ring radius resolution measured is 1.6%.

  18. The SELEX phototube RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Engelfried, J.; Filimonov, I.; Kilmer, J.; Kozhevnikov, A.; Kubarovsky, V.; Molchanov, V.; Nemitkin, A.; Ramberg, E.; Rud, V.; Stutte, L

    1999-07-11

    In this article, construction, operation, and performance of the RICH detector of Fermilab experiment 781 (SELEX) are described. The detector utilizes a matrix of 2848 phototubes for the photocathode to detect Cherenkov photons generated in a 10 m neon radiator. For the central region an N{sub 0} of 104 cm{sup -1}, corresponding to 13.6 hits on a {beta}=1 ring, was obtained. The ring radius resolution measured is 1.6%. (author)

  19. The SELEX phototube RICH detector

    Science.gov (United States)

    Engelfried, J.; Filimonov, I.; Kilmer, J.; Kozhevnikov, A.; Kubarovsky, V.; Molchanov, V.; Nemitkin, A.; Ramberg, E.; Rud, V.; Stutte, L.

    1999-07-01

    In this article, construction, operation, and performance of the RICH detector of Fermilab experiment 781 (SELEX) are described. The detector utilizes a matrix of 2848 phototubes for the photocathode to detect Cherenkov photons generated in a 10 m neon radiator. For the central region an N0 of 104 cm-1, corresponding to 13.6 hits on a β=1 ring, was obtained. The ring radius resolution measured is 1.6%.

  20. New class of neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Czirr, J.B.

    1997-09-01

    An optimized neutron scattering instrument design must include all significant components, including the detector. For example, useful beam intensity is limited by detector dead time; detector pixel size determines the optimum beam diameter, sample size, and sample to detector distance; and detector efficiency vs. wavelength determines the available energy range. As an example of the next generation of detectors that could affect overall instrumentation design, we will describe a new scintillator material that is potentially superior to currently available scintillators. We have grown and tested several small, single crystal scintillators based upon the general class of cerium-activated lithium lanthanide borates. The outstanding characteristic of these materials is the high scintillation efficiency-as much as five times that of Li-glass scintillators. This increase in light output permits the practical use of the exothermic B (n, alpha) reaction for low energy neutron detection. This reaction provides a four-fold increase in capture cross section relative to the Li (n, alpha) reaction, and the intriguing possibility of demanding a charged-particle/gamma ray coincidence to reduce background detection rates. These new materials will be useful in the thermal and epithermal energy ran at reactors and pulsed neutron sources.