WorldWideScience

Sample records for radiation detector materials

  1. Radiation detectors based by polymer materials

    International Nuclear Information System (INIS)

    Cherestes, Margareta; Cherestes, Codrut; Constantinescu, Livia

    2004-01-01

    Scintillation counters make use of the property of certain chemical compounds to emit short light pulses after excitation produced by the passage of charged particles or photons of high energy. These flashes of light are detected by a photomultiplier tube that converts the photons into a voltage pulse. The light emitted from the detector also can be collected, focussed and dispersed by a CCD detector. The study of the evolution of the light emission and of the radiation damage under irradiation is a primary topic in the development of radiation hard polymer based scintillator. Polymer scintillator thin films are used in monitoring radiation beam intensities and simultaneous counting of different radiations. Radiation detectors have characteristics which depend on: the type of radiation, the energy of radiation, and the material of the detector. Three types of polymer thin films were studied: a polyvinyltoluene based scintillator, fluorinated polyimide and PMMA. (authors)

  2. Instrumentation for characterizing materials and composed semiconductors for ionizing radiation detectors

    International Nuclear Information System (INIS)

    Paschoal, Arquimedes J.A.; Leite, Adolfo M.B.; Nazzre, Fabio V.B.; Santos, Luiz A.P.

    2007-01-01

    The purpose of this work is the development of instrumentation for characterizing some type of ionizing radiation detectors. Those detectors are being manufactured by the Nuclear Instrumentation Laboratory at CRCN/Recife and can be used both on photon beam and with particles. Such detectors consist of semiconductor material in the form of films generated by oxide growing or by means of semiconductor material deposition in a substrate. Those materials can be made of metals, semi-metals, composites or semiconductor polymers. Prior to expose those detectors to ionizing radiation, it must be physically and electrically characterized. In this intention it was developed an electromechanical system. An electrical circuit was built to measure the signal from the detector and another circuit to control the movement of four probes (4-points technique) by using a stepper motor and the micro stepping technique avoiding damage to the detector. This system can be of interest to researchers that work with a sort of semiconductor materials in the form of thin film and in nanotechnological processes aiming the design of radiation ionizing detectors. (author)

  3. Radiation damage in barium fluoride detector materials

    International Nuclear Information System (INIS)

    Levey, P.W.; Kierstead, J.A.; Woody, C.L.

    1988-01-01

    To develop radiation hard detectors, particularly for high energy physics studies, radiation damage is being studied in BaF 2 , both undoped and doped with La, Ce, Nd, Eu, Gd and Tm. Some dopants reduce radiation damage. In La doped BaF 2 they reduce the unwanted long lifetime luminescence which interferes with the short-lived fluorescence used to detect particles. Radiation induced coloring is being studied with facilities for making optical measurements before, during and after irradiation with 60 C0 gamma rays. Doses of 10 6 rad, or less, create only ionization induced charge transfer effects since lattice atom displacement damage is negligible at these doses. All crystals studied exhibit color center formation, between approximately 200 and 800 nm, during irradiation and color center decay after irradiation. Thus only measurements made during irradiation show the total absorption present in a radiation field. Both undoped and La doped BaF 2 develop damage at minimum detectable levels in the UV---which is important for particle detectors. For particle detector applications these studies must be extended to high dose irradiations with particles energetic enough to cause lattice atom displacement damage. In principle, the reduction in damage provided by dopants could apply to other applications requiring radiation damage resistant materials

  4. Radiation detectors

    International Nuclear Information System (INIS)

    2013-01-01

    This sixth chapter presents the operational principles of the radiation detectors; detection using photographic emulsions; thermoluminescent detectors; gas detectors; scintillation detectors; liquid scintillation detectors; detectors using semiconductor materials; calibration of detectors; Bragg-Gray theory; measurement chain and uncertainties associated to measurements

  5. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.

    2005-01-01

    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  6. Diamond radiation detectors II. CVD diamond development for radiation detectors

    International Nuclear Information System (INIS)

    Kania, D.R.

    1997-01-01

    Interest in radiation detectors has supplied some of the impetus for improving the electronic properties of CVD diamond. In the present discussion, we will restrict our attention to polycrystalhne CVD material. We will focus on the evolution of these materials over the past decade and the correlation of detector performance with other properties of the material

  7. Silicon carbide and its use as a radiation detector material

    International Nuclear Information System (INIS)

    Nava, F; Bertuccio, G; Cavallini, A; Vittone, E

    2008-01-01

    We present a comprehensive review of the properties of the epitaxial 4H silicon carbide polytype (4H–SiC). Particular emphasis is placed on those aspects of this material related to room, high-temperature and harsh environment ionizing radiation detector operation. A review of the characterization methods and electrical contacting issues and how these are related to detector performance is presented. The most recent data on charge transport parameters across the Schottky barrier and how these are related to radiation spectrometer performance are presented. Experimental results on pixel detectors having equivalent noise energies of 144 eV FWHM (7.8 electrons rms) and 196 eV FWHM at +27 °C and +100 °C, respectively, are reported. Results of studying the radiation resistance of 4H–SiC are analysed. The data on the ionization energies, capture cross section, deep-level centre concentrations and their plausible structures formed in SiC as a result of irradiation with various particles are reviewed. The emphasis is placed on the study of the 1 MeV neutron irradiation, since these thermal particles seem to play the main role in the detector degradation. An accurate electrical characterization of the induced deep-level centres by means of PICTS technique has allowed one to identify which play the main role in the detector degradation. (topical review)

  8. Radiation Hardening of Silicon Detectors

    CERN Multimedia

    Leroy, C; Glaser, M

    2002-01-01

    %RD48 %title\\\\ \\\\Silicon detectors will be widely used in experiments at the CERN Large Hadron Collider where high radiation levels will cause significant bulk damage. In addition to increased leakage current and charge collection losses worsening the signal to noise, the induced radiation damage changes the effective doping concentration and represents the limiting factor to long term operation of silicon detectors. The objectives are to develop radiation hard silicon detectors that can operate beyond the limits of the present devices and that ensure guaranteed operation for the whole lifetime of the LHC experimental programme. Radiation induced defect modelling and experimental results show that the silicon radiation hardness depends on the atomic impurities present in the initial monocrystalline material.\\\\ \\\\ Float zone (FZ) silicon materials with addition of oxygen, carbon, nitrogen, germanium and tin were produced as well as epitaxial silicon materials with epilayers up to 200 $\\mu$m thickness. Their im...

  9. Self-powered radiation detector

    International Nuclear Information System (INIS)

    Playfoot, K.C.; Bauer, R.F.; Goldstein, N.P.

    1980-01-01

    This invention relates to a self powered radiation detector requiring no excitation potential to generate a signal indicating a radiation flux. Such detectors comprise two electrically insulated electrodes, at a distance from each other. These electrodes are made of conducting materials having a different response for neutron and/or gamma ray radiation flux levels, as in nuclear power stations. This elongated detector generates an electric signal in terms of an incident flux of radiations cooperating with coaxial conductors insulated from each other and with different radiation reaction characteristics. The conductor with the greatest reaction to the radiations forms the central emitting electrode and the conductor with the least reaction to the radiations forms a tubular coaxial collecting electrode. The rhodium or cobalt tubular emitting electrode contains a ductile central conducting cable placed along the longitudinal axis of the detector. The latter is in high nickel steel with a low reaction to radiation [fr

  10. Workshops on radiation imaging detectors

    International Nuclear Information System (INIS)

    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.

    2005-01-01

    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

  11. 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.

  12. Semiconductor radiation detectors technology and applications

    CERN Document Server

    2018-01-01

    The aim of this book is to educate the reader on radiation detectors, from sensor to read-out electronics to application. Relatively new detector materials, such as CdZTe and Cr compensated GaAs, are introduced, along with emerging applications of radiation detectors. This X-ray technology has practical applications in medical, industrial, and security applications. It identifies materials based on their molecular composition, not densities as the traditional transmission equipment does. With chapters written by an international selection of authors from both academia and industry, the book covers a wide range of topics on radiation detectors, which will satisfy the needs of both beginners and experts in the field.

  13. Radiation detector

    International Nuclear Information System (INIS)

    Gillies, W.

    1980-01-01

    The radiation detector for measuring e.g. a neutron flux consists of a central emitter, an insulating shell arranged around it, and a tube-shaped collector enclosing both. The emitter itself is composed of a great number of stranded, spiral wires of small diameter giving a defined flexibility to the detector. For emitter material Pt, Rh, V, Co, Ce, Os or Ta may be used. (DG) [de

  14. Silicon radiation detectors: materials and applications

    International Nuclear Information System (INIS)

    Walton, J.T.; Haller, E.E.

    1982-10-01

    Silicon nuclear radiation detectors are available today in a large variety of sizes and types. This profusion has been made possible by the ever increasing quality and diameter silicon single crystals, new processing technologies and techniques, and innovative detector design. The salient characteristics of the four basic detector groups, diffused junction, ion implanted, surface barrier, and lithium drift are reviewed along with the silicon crystal requirements. Results of crystal imperfections detected by lithium ion compensation are presented. Processing technologies and techniques are described. Two recent novel position-sensitive detector designs are discussed - one in high-energy particle track reconstruction and the other in x-ray angiography. The unique experimental results obtained with these devices are presented

  15. Self-powered radiation detectors

    International Nuclear Information System (INIS)

    Gillies, Wallace.

    1980-01-01

    This invention aims to create a self fed radiation detector comprising a long central emitter-conductor absorbing the neutrons, wrapped in an insulating material, and a thin collector-conductor placed coaxially around the emitter and the insulation, the emitter being constructed of several stranded cables in a given conducting material so that the detector is flexible enough [fr

  16. Towards radiation hard converter material for SiC-based fast neutron detectors

    Science.gov (United States)

    Tripathi, S.; Upadhyay, C.; Nagaraj, C. P.; Venkatesan, A.; Devan, K.

    2018-05-01

    In the present work, Geant4 Monte-Carlo simulations have been carried out to study the neutron detection efficiency of the various neutron to other charge particle (recoil proton) converter materials. The converter material is placed over Silicon Carbide (SiC) in Fast Neutron detectors (FNDs) to achieve higher neutron detection efficiency as compared to bare SiC FNDs. Hydrogenous converter material such as High-Density Polyethylene (HDPE) is preferred over other converter materials due to the virtue of its high elastic scattering reaction cross-section for fast neutron detection at room temperature. Upon interaction with fast neutrons, hydrogenous converter material generates recoil protons which liberate e-hole pairs in the active region of SiC detector to provide a detector signal. The neutron detection efficiency offered by HDPE converter is compared with several other hydrogenous materials viz., 1) Lithium Hydride (LiH), 2) Perylene, 3) PTCDA . It is found that, HDPE, though providing highest efficiency among various studied materials, cannot withstand high temperature and harsh radiation environment. On the other hand, perylene and PTCDA can sustain harsh environments, but yields low efficiency. The analysis carried out reveals that LiH is a better material for neutron to other charge particle conversion with competent efficiency and desired radiation hardness. Further, the thickness of LiH has also been optimized for various mono-energetic neutron beams and Am-Be neutron source generating a neutron fluence of 109 neutrons/cm2. The optimized thickness of LiH converter for fast neutron detection is found to be ~ 500 μm. However, the estimated efficiency for fast neutron detection is only 0.1%, which is deemed to be inadequate for reliable detection of neutrons. A sensitivity study has also been done investigating the gamma background effect on the neutron detection efficiency for various energy threshold of Low-Level Discriminator (LLD). The detection

  17. Status of radiation detector and neutron monitor technology

    CERN Document Server

    Kim, Y K; Ha, J H; Han, S H; Hong, S B; Hwang, I K; Lee, W G; Moon, B S; Park, S H; Song, M H

    2002-01-01

    In this report, we describe the current states of the radiation detection technology, detectors for industrial application, and neutron monitors. We also survey the new technologies being applied to this field. The method to detect radiation is the measurement of the observable secondary effect from the interaction between incident radiation and detector material, such as ionization, excitation, fluorescence, and chemical reaction. The radiation detectors can be categorized into gas detectors, scintillation detectors, and semiconductor detectors according to major effects and main applications. This report contains the current status and operational principles of these detectors. The application fields of radiation detectors are industrial measurement system, in-core neutron monitor, medical radiation diagnostic device, nondestructive inspection device, environmental radiation monitoring, cosmic-ray measurement, security system, fundamental science experiment, and radiation measurement standardization. The st...

  18. 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.

  19. Gamma radiation detectors for safeguards applications

    International Nuclear Information System (INIS)

    Carchon, R.; Moeslinger, M.; Bourva, L.; Bass, C.; Zendel, M.

    2007-01-01

    The IAEA uses extensively a variety of gamma radiation detectors to verify nuclear material. These detectors are part of standardized spectrometry systems: germanium detectors for High-Resolution Gamma Spectrometry (HRGS); Cadmium Zinc Telluride (CZT) detectors for Room Temperature Gamma Spectrometry (RTGS); and NaI(Tl) detectors for Low Resolution Gamma Spectrometry (LRGS). HRGS with high-purity Germanium (HpGe) detectors cooled by liquid nitrogen is widely used in nuclear safeguards to verify the isotopic composition of plutonium or uranium in non-irradiated material. Alternative cooling systems have been evaluated and electrically cooled HpGe detectors show a potential added value, especially for unattended measurements. The spectrometric performance of CZT detectors, their robustness and simplicity are key to the successful verification of irradiated materials. Further development, such as limiting the charge trapping effects in CZT to provide improved sensitivity and energy resolution are discussed. NaI(Tl) detectors have many applications-specifically in hand-held radioisotope identification devices (RID) which are used to detect the presence of radioactive material where a lower resolution is sufficient, as they benefit from a generally higher sensitivity. The Agency is also continuously involved in the review and evaluation of new and emerging technologies in the field of radiation detection such as: Peltier-cooled CdTe detectors; semiconductor detectors operating at room temperature such as HgI 2 and GaAs; and, scintillator detectors using glass fibres or LaBr 3 . A final conclusion, proposing recommendations for future action, is made

  20. Property of the diamond radiation detector

    International Nuclear Information System (INIS)

    Sochor, V.; Cechak, T.; Sopko, B.

    2008-01-01

    The outstanding properties of diamond, such as radiation hardness, high carrier mobility, high band gap and breakdown field, distinguish it as a good candidate for radiation detectors. In the dosimetry for radiotherapy is permanently searched the detector with high sensitivity, high stability, linear dependence of the response, small size, tissue equivalent material and fast response, for the measuring of the temporal and space variations of the dose. The diamond detector properties as high sensitivity, good spatial and temporal resolution, low Leakage currents, low capacitance, possibility to fabricate robust and compact device and high temperature operation make it possible to use these detectors in many fields from high energy physics till radiation monitoring, from Medical therapy dosimetry till synchrotron radiation measurement. (authors)

  1. Electromagnetic radiation detector

    Science.gov (United States)

    Benson, Jay L.; Hansen, Gordon J.

    1976-01-01

    An electromagnetic radiation detector including a collimating window, a cathode member having a photoelectric emissive material surface angularly disposed to said window whereby radiation is impinged thereon at acute angles, an anode, separated from the cathode member by an evacuated space, for collecting photoelectrons emitted from the emissive cathode surface, and a negatively biased, high transmissive grid disposed between the cathode member and anode.

  2. Semiconductor high-energy radiation scintillation detector

    International Nuclear Information System (INIS)

    Kastalsky, A.; Luryi, S.; Spivak, B.

    2006-01-01

    We propose a new scintillation-type detector in which high-energy radiation generates electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. An important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombination time of minority carriers. Notably, the fast response comes without any degradation in brightness. When the scintillator is implemented in a qualified semiconductor material (such as InP or GaAs), the photo-detector and associated circuits can be epitaxially integrated on the scintillator slab and the structure can be stacked-up to achieve virtually any desired absorption capability

  3. Radiation detectors for reactors

    International Nuclear Information System (INIS)

    Balagi, V.

    2005-01-01

    Detection and measurement of radiation plays a vital role in nuclear reactors from the point of view of control and safety, personnel protection and process control applications. Various types of radiation are measured over a wide range of intensity. Consequently a variety of detectors find use in nuclear reactors. Some of these devices have been developed in Electronics Division. They include gas-filled detectors such as 10 B-lined proportional counters and chambers, fission detectors and BF 3 counters are used for the measurement of neutron flux both for reactor control and safety, process control as well as health physics instrumentation. In-core neutron flux instrumentation employs the use detectors such as miniature fission detectors and self-powered detectors. In this development effort, several indigenous materials, technologies and innovations have been employed to suit the specific requirement of nuclear reactor applications. This has particular significance in view of the fact that several new types of reactors such as P-4, PWR and AHWR critical facilities, FBTR, PFBR as well as the refurbishment of old units like CIRUS are being developed. The development work has sought to overcome some difficulties associated with the non-availability of isotopically enriched neutron-sensing materials, achieving all-welded construction etc. The present paper describes some of these innovations and performance results. (author)

  4. Semiconductor radiation detector

    Science.gov (United States)

    Bell, Zane W.; Burger, Arnold

    2010-03-30

    A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

  5. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1996-01-01

    The National Institute for Nuclear Research has established a Radiation detector laboratory that has the possibility of providing to the consultants on the handling and applications of the nuclear radiation detectors. It has special equipment to repair the radiation detectors used in spectroscopy as the hyper pure Germanium for gamma radiation and the Lithium-silica for X-rays. There are different facilities in the laboratory that can become useful for other institutions that use radiation detectors. This laboratory was created to satisfy consultant services, training and repairing of the radiation detectors both in national and regional levels for Latin America. The laboratory has the following sections: Nuclear Electronic Instrumentation; where there are all kind of instruments for the measurement and characterization of detectors like multichannel analyzers of pulse height, personal computers, amplifiers and nuclear pulse preamplifiers, nuclear pulses generator, aleatories, computer programs for radiation spectra analysis, etc. High vacuum; there is a vacuum escape measurer, two high vacuum pumps to restore the vacuum of detectors, so the corresponding measurers and the necessary tools. Detectors cleaning; there is an anaerobic chamber for the detectors handling at inert atmosphere, a smoke extraction bell for cleaning with the detector solvents. Cryogenic; there are vessels and tools for handling liquid nitrogen which is used for cooling the detectors when they required it. (Author)

  6. Development of leak detector by radiation. 2

    International Nuclear Information System (INIS)

    Suzuki, Takashi; Okano, Yasuhiro; Chisaka, Haruo

    1997-01-01

    Leak detector by radiation has been developed by cooperative research between Water Authority and us. In his fiscal year, the most suitable arrangement of detector system was simulated by Monte Carlo method. The first, the experimental values were compared with the results of simulation. The second, calculation was carried out by changing the quality of reflective materials and distance between radiation source and detector. The simulation results were agreed with the experimental results. On the basis of the rate of presence of leak, the most suitable arrangement of detector system was obtained under the conditions that both radiation source and detector covered with graphite or iron of 5 cm thickness and separated each other 3 cm apart. However, by comparing FOM (figure of merit), the suitable arrangement was that radiation source and detector adjoined each other and covered by graphite or iron of 20 cm thickness. (S.Y.)

  7. 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...

  8. ALICE Transition Radiation Detector (TRD), test beam.

    CERN Multimedia

    2003-01-01

    Electrons and positrons can be discriminated from other charged particles using the emission of transition radiation - X-rays emitted when the particles cross many layers of thin materials. To develop such a Transition Radiation Detector(TRD) for ALICE many detector prototypes were tested in mixed beams of pions and electrons, as in the example shown here.

  9. Experimental studies of radiation damage of silicon detectors

    International Nuclear Information System (INIS)

    Angelescu, T.; Ghete, V.M.; Ghiordanescu, N.; Lazanu, I.; Mihul, A.; Golutvin, I.; Lazanu, S.; Savin, I.; Vasilescu, A.; Biggeri, U.; Borchi, E.; Bruzzi, M.; Li, Z.; Kraner, H.W.

    1994-02-01

    New particle physics experiments are correlated with high luminosity and/or high energy. The new generation of colliding beam machines which will be constructed will make an extrapolation of a factor of 100 in the center of mass energy and of 1000 in luminosity beyond present accelerators. The scientific community hopes that very exciting physics results could be achieved this way, from the solution to the problem of electroweak symmetry breaking to the possible discovery of new, unpredicted phenomena. The particles which compose the radiation field are: electrons, pions, neutrons, protons and photons. It has become evident that the problem of the radiation resistance of detectors in this severe environment is a crucial one. This situation is complicated more by the fact that detectors must work all the run time of the machine, and better all the time of the experiment, without replacement (part or whole). So, studies related to the investigation of the radiation hardness of all detector parts, are developing. The studies are in part material and device characterization after irradiation, and in part technological developments, made in order to find harder, cheaper technologies, for larger surfaces. Semiconductor detectors have proven to be a good choice for vertex and calorimeter. Both fixed target machines and colliders had utilized in the past silicon junction detectors as the whole or part of the detection system. Precision beam hodoscopes and sophisticated trigger devices with silicon are equally used. The associated electronics in located near the detectors, and is subjected to the same radiation fields. Studies of material and device radiation hardness are developing in parallel. Here the authors present results on the radiation hardness of silicon, both as a bulk material and as detectors, to neutron irradiation at high fluences

  10. Development of Radiation Hard Radiation Detectors, Differences between Czochralski Silicon and Float Zone Silicon

    CERN Document Server

    Tuominen, Eija

    2012-01-01

    The purpose of this work was to develop radiation hard silicon detectors. Radiation detectors made ofsilicon are cost effective and have excellent position resolution. Therefore, they are widely used fortrack finding and particle analysis in large high-energy physics experiments. Silicon detectors willalso be used in the CMS (Compact Muon Solenoid) experiment that is being built at the LHC (LargeHadron Collider) accelerator at CERN (European Organisation for Nuclear Research). This work wasdone in the CMS programme of Helsinki Institute of Physics (HIP).Exposure of the silicon material to particle radiation causes irreversible defects that deteriorate theperformance of the silicon detectors. In HIP CMS Programme, our approach was to improve theradiation hardness of the silicon material with increased oxygen concentration in silicon material. Westudied two different methods: diffusion oxygenation of Float Zone silicon and use of high resistivityCzochralski silicon.We processed, characterised, tested in a parti...

  11. Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, P.H., E-mail: pinghe.lu@redlen.com; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A.W.

    2015-06-01

    This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments. - Highlights: • We developed ruggedization methods to enhance reliability of CZT detector assemblies. • Attachment of CZT radiation detectors was improved through comparative studies. • Bare detector metallization

  12. Radiometric analyzer with plural radiation sources and detectors

    International Nuclear Information System (INIS)

    Arima, S.; Oda, M.; Miyashita, K.; Takada, M.

    1977-01-01

    A radiometric analyzer for measuring characteristics of a material by radiation comprises a plurality of systems in which each consists of a radiation source and a radiation detector which are the same in number as the number of elements of the molecule of the material and a linear calibration circuit having inverse response characteristics (calibration curve) of the respective systems of detectors, whereby the measurement is carried out by four fundamental rules by operation of the mutual outputs of said detector system obtained through said linear calibration circuit. One typical embodiment is a radiometric analyzer for hydrocarbons which measures the density of heavy oil, the sulfur content and the calorific value by three detector systems which include a γ-ray source (E/sub γ/ greater than 50 keV), a soft x-ray source (Ex approximately 20 keV), and a neutron ray source. 2 claims, 6 figures

  13. The Cherenkov correlated timing detector: materials, geometry and timing constraints

    International Nuclear Information System (INIS)

    Aronstein, D.; Bergfeld, T.; Horton, D.; Palmer, M.; Selen, M.; Thayer, G.; Boyer, V.; Honscheid, K.; Kichimi, H.; Sugaya, Y.; Yamaguchi, H.; Yoshimura, Y.; Kanda, S.; Olsen, S.; Ueno, K.; Tamura, N.; Yoshimura, K.; Lu, C.; Marlow, D.; Mindas, C.; Prebys, E.; Pomianowski, P.

    1996-01-01

    The key parameters of Cherenkov correlated timing (CCT) detectors are discussed. Measurements of radiator geometry, optical properties of radiator and coupling materials, and photon detector timing performance are presented. (orig.)

  14. Gamma-ray detectors for intelligent, hand-held radiation monitors

    International Nuclear Information System (INIS)

    Fehlau, P.E.

    1983-01-01

    Small radiation detectors based on HgI 2 , bismuth germanate (BGO), plastic, or NaI(Tl) detector materials were evaluated for use in small, lighweight radiation monitors. The two denser materials, HgI 2 and BGO, had poor resolution at low-energy and thus performed less well than NaI(Tl) in detecting low-energy gamma rays from bare, enriched uranium. The plastic scintillator, a Compton recoil detector, also performed less well at low gamma-ray energy. Two small NaI(Tl) detectors were suitable for detecting bare uranium and sheilded plutonium. One became part of a new lightweight hand-held monitor and the other found uses as a pole-mounted detector for monitoring hard-to-reach locations

  15. Radiation detectors as surveillance monitors

    International Nuclear Information System (INIS)

    Fehlau, P.E.; Dowdy, E.J.

    1981-01-01

    The International Atomic Energy Agency (IAEA) proposes to use personnel dosimetry radiation detectors as surveillance monitors for safeguards purposes. It plans to place these YES/NO monitors at barrier penetration points declared closed under IAEA safeguards to detect the passage of plutonium-bearing nuclear material, usually spent fuel. For this application, commercially available dosimeters were surveyed as well as other radiation detectors that appeared suitable and likely to be marketed in the near future. No primary advantage was found in a particular detector type because in this application backgrounds vary during long counting intervals. Secondary considerations specify that the monitor be inexpensive and easy to tamper-proof, interrogate, and maintain. On this basis radiophotoluminescent, thermoluminescent, and electronic dosimeters were selected as possible routine monitors; the latter two may prove useful for data-base acquisition

  16. Department of Radiation Detectors: Overview

    International Nuclear Information System (INIS)

    Piekoszewski, J.

    1998-01-01

    (full text) Work carried out in 1997 in the Department of Radiation Detectors concentrated on three subjects: (i) Semiconductor Detectors (ii) X-ray Tube Generators (iii) Material Modification using Ion and Plasma Beams. Semiconductor detectors: Semiconductor detectors of ionizing radiation are among the basic tools utilized in such fields of research and industry as nuclear physics, high energy physics, medical (oncology) radiotherapy, radiological protection, environmental monitoring, energy dispersive X-ray fluorescence non-destructive analysis of chemical composition, nuclear power industry. The Department all objectives are: - search for new types of detectors, - adapting modern technologies (especially of industrial microelectronics) to detector manufacturing, - producing unique detectors tailored for physics experiments, - manufacturing standard detectors for radiation measuring instruments, - scientific development of the staff. These 1997 objectives were accomplished particularly by: - research on unique detectors for nuclear physics (e.g. transmission type Si(Li) detectors with extremely thin entrance and exit window), - development of technology of high-resistivity (HRSi) silicon detectors and thermoelectric cooling systems (KBN grant), - study of the applicability of industrial planar technology in producing detectors, - manufacturing detectors developed in previous years, re-generating and servicing customer detectors of various origin. In accomplishing of the above, the Department cooperated with interested groups of physicists from our Institute (P-I and P-II Departments), Warsaw University, Warsaw Heavy Ion Laboratory and with some technology Institutes based in Warsaw (ITME, ITE). Some detectors and services have been delivered to customers on a commercial basis. X-Rat tube generators: The Department conducts research on design and technology of producing X-ray generators based on X-ray tubes of special construction. In 1997, work on a special

  17. Radiation damage in silicon. Defect analysis and detector properties

    Energy Technology Data Exchange (ETDEWEB)

    Hoenniger, F.

    2008-01-15

    Silicon microstrip and pixel detectors are vital sensor-components as particle tracking detectors for present as well as future high-energy physics (HEP) experiments. All experiments at the large Hadron Collider (LHC) are equipped with such detectors. Also for experiments after the upgrade of the LHC (the so-called Super-LHC), with its ten times higher luminosity, or the planned International Linear Collider (ILC) silicon tracking detectors are forseen. Close to the interaction region these detectors have to face harsh radiation fields with intensities above the presently tolerable level. defect engineering of the used material, e. g. oxygen enrichment of high resistivity float zone silicon and growing of thin low resistivityepitaxial layers on Czochralski silicon substrates has been established to improve the radiation hardness of silicon sensors. This thesis focuses mainly on the investigation of radiation induced defects and their differences observed in various kinds of epitaxial silicon material. Comparisons with other materials like float zone or Czochralski silicon are added. Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) measurements have been performed after {gamma}-, electron-, proton- and neutron-irradiation. The differenced in the formation of vacancy and interstitial related defects as well as so-called clustered regions were investigated for various types of irradiation. In addition to the well known defects VO{sub i}, C{sub i}O{sub i}, C{sub i}C{sub s}, VP or V{sub 2} several other defect complexes have been found and investigated. Also the material dependence of the defect introduction rates and the defect annealing behavior has been studied by isothermal and isochronal annealing experiments. Especially the IO{sub 2} defect which is an indicator for the oxygen-dimer content of the material has been investigated in detail. On the basis of radiation induced defects like the bistable donor (BD) defect and a deep

  18. Radiation damage in silicon. Defect analysis and detector properties

    International Nuclear Information System (INIS)

    Hoenniger, F.

    2008-01-01

    Silicon microstrip and pixel detectors are vital sensor-components as particle tracking detectors for present as well as future high-energy physics (HEP) experiments. All experiments at the large Hadron Collider (LHC) are equipped with such detectors. Also for experiments after the upgrade of the LHC (the so-called Super-LHC), with its ten times higher luminosity, or the planned International Linear Collider (ILC) silicon tracking detectors are forseen. Close to the interaction region these detectors have to face harsh radiation fields with intensities above the presently tolerable level. defect engineering of the used material, e. g. oxygen enrichment of high resistivity float zone silicon and growing of thin low resistivityepitaxial layers on Czochralski silicon substrates has been established to improve the radiation hardness of silicon sensors. This thesis focuses mainly on the investigation of radiation induced defects and their differences observed in various kinds of epitaxial silicon material. Comparisons with other materials like float zone or Czochralski silicon are added. Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) measurements have been performed after γ-, electron-, proton- and neutron-irradiation. The differenced in the formation of vacancy and interstitial related defects as well as so-called clustered regions were investigated for various types of irradiation. In addition to the well known defects VO i , C i O i , C i C s , VP or V 2 several other defect complexes have been found and investigated. Also the material dependence of the defect introduction rates and the defect annealing behavior has been studied by isothermal and isochronal annealing experiments. Especially the IO 2 defect which is an indicator for the oxygen-dimer content of the material has been investigated in detail. On the basis of radiation induced defects like the bistable donor (BD) defect and a deep acceptor, a model has been introduced to

  19. Optimized mounting of a polyethylene naphthalate scintillation material in a radiation detector.

    Science.gov (United States)

    Nakamura, Hidehito; Yamada, Tatsuya; Shirakawa, Yoshiyuki; Kitamura, Hisashi; Shidara, Zenichiro; Yokozuka, Takayuki; Nguyen, Philip; Kanayama, Masaya; Takahashi, Sentaro

    2013-10-01

    Polyethylene naphthalate (PEN) has great potential as a scintillation material for radiation detection. Here the optimum mounting conditions to maximize the light collection efficiency from PEN in a radiation detector are discussed. To this end, we have determined light yields emitted from irradiated PEN for various optical couplings between the substrate and the photodetector, and for various substrate surface treatments. The results demonstrate that light extraction from PEN is more sensitive to the optical couplings due to its high refractive index. We also assessed the extent of radioactive impurities in PEN as background sources and found that the impurities are equivalent to the environmental background level. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. 18th International Workshop on Radiation Imaging Detectors

    CERN Document Server

    2016-01-01

    The International Workshops on Radiation Imaging Detectors are held yearly and provide an international forum for discussing current research and developments in the area of position sensitive detectors for radiation imaging, including semiconductor detectors, gas and scintillator-based detectors. Topics include processing and characterization of detector materials, hybridization and interconnect technologies, design of counting or integrating electronics, readout and data acquisition systems, and applications in various scientific and industrial fields. The workshop will have plenary sessions with invited and contributed papers presented orally and in poster sessions. The invited talks will be chosen to review recent advances in different areas covered in the workshop.

  1. Photovoltaic radiation detector element

    International Nuclear Information System (INIS)

    Agouridis, D.C.

    1980-01-01

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein in the edge of which closely approaches but is spaced from the current collector strips

  2. Nuclear radiation detectors

    International Nuclear Information System (INIS)

    Kapoor, S.S.; Ramamurthy, V.S.

    1986-01-01

    The present monograph is intended to treat the commonly used detectors in the field of nuclear physics covering important developments of the recent years. After a general introduction, a brief account of interaction of radiation with matter relevant to the processes in radiation detection is given in Chapter II. In addition to the ionization chamber, proportional counters and Geiger Mueller counters, several gas-filled detectors of advanced design such as those recently developed for heavy ion physics and other types of studies have been covered in Chapter III. Semiconductor detectors are dealt with in Chapter IV. The scintillation detectors which function by sensing the photons emitted by the luminescence process during the interaction of the impinging radiation with the scintillation detector medium are described in Chapter V. The topic of neutron detectors is covered in Chapter VI, as in this case the emphasis is more on the method of neutron detection rather than on detector type. Electronic instrumentation related to signal pulse processing dealt with in Chapter VII. The track etch detectors based on the visualization of the track of the impinging charge particle have also been briefly covered in the last chapter. The scope of this monograph is confined to detectors commonly used in low and medium energy nuclear physics research and applications of nuclear techniques. The monograph is intended for post-graduate students and those beginning to work with the radiation detectors. (author)

  3. Multi-directional radiation detector using photographic film

    International Nuclear Information System (INIS)

    Junet, L K; Majid, Z A Abdul; Sapuan, A H; Sayed, I S; Pauzi, N F

    2014-01-01

    Ionising radiation has always been part of our surrounding and people are continuously exposed to it. Ionising radiation is harmful to human health, thus it is vital to monitor the radiation. To monitor radiation, there are three main points that should be observed cautiously, which are energy, quantity, and direction of the radiation sources. A three dimensional (3D) dosimeter is an example of a radiation detector that provide these three main points. This dosimeter is able to record the radiation dose distribution in 3D. Applying the concept of dose detection distribution, study has been done to design a multi-directional radiation detector of different filter thicknesses. This is obtained by designing a cylinder shaped aluminum filter with several layers of different thickness. Black and white photographic material is used as a radiation-sensitive material and a PVC material has been used as the enclosure. The device is then exposed to a radiation source with different exposure factors. For exposure factor 70 kVp, 16 mAs; the results have shown that optical density (OD) value at 135° is 1.86 higher compared with an OD value at 315° which is 0.71 as the 135° area received more radiation compare to 315° region. Furthermore, with an evidence of different angle of film give different value of OD shows that this device has a multidirectional ability. Materials used to develop this device are widely available in the market, thus reducing the cost of development and making it suitable for commercialisation

  4. Radiation emitter-detector package

    International Nuclear Information System (INIS)

    O'Brien, J.T.; Limm, A.C.; Nyul, P.; Tassia, V.S. Jr.

    1978-01-01

    Mounted on the metallic base of a radiation emitter-detector is a mounting block is a first projection, and a second projection. A radiation detector is on the first projection and a semiconductor electroluminescent device, i.e., a radiation emitter, is on the second projection such that the plane of the recombination region of the electroluminescent device is perpendicular to the radiation incident surface of the radiation detector. The electroluminescent device has a primary emission and a secondary emission in a direction different from the primary emission. A radiation emitter-detector package as described is ideally suited to those applications wherein the secondary radiation of the electroluminescent device is fed into a feedback circuit regulating the biasing current of the electroluminescent device

  5. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1997-01-01

    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)

  6. Radiation effects on II-VI compound-based detectors

    CERN Document Server

    Cavallini, A; Dusi, W; Auricchio, N; Chirco, P; Zanarini, M; Siffert, P; Fougeres, P

    2002-01-01

    The performance of room temperature CdTe and CdZnTe detectors exposed to a radiation source can be strongly altered by the interaction of the ionizing particles and the material. Up to now, few experimental data are available on the response of II-VI compound detectors to different types of radiation sources. We have carried out a thorough investigation on the effects of gamma-rays, neutrons and electron irradiation both on CdTe : Cl and Cd sub 0 sub . sub 9 Zn sub 0 sub . sub 1 Te detectors. We have studied the detector response after radiation exposure by means of dark current measurements and of quantitative spectroscopic analyses at low and medium energies. The deep traps present in the material have been characterized by means of PICTS (photo-induced current transient spectroscopy) analyses, which allow to determine the trap apparent activation energy and capture cross-section. The evolution of the trap parameters with increasing irradiation doses has been monitored for all the different types of radiati...

  7. The role of contacts in semiconductor gamma radiation detectors

    International Nuclear Information System (INIS)

    Lachish, U.

    1998-01-01

    It is proposed that the operation of semiconductor gamma radiation detectors, equipped with ohmic contacts, which allow free electron flow between the contacts and bulk material, will not be sensitive to low hole mobility, hole collection efficiency, or hole trapping. Such fast-operating detectors may be readily integrated into monolithic arrays. The detection mechanism and various material aspects are discussed and compared to those of blocking contact detectors. Some suggestions for detector realization are presented. (orig.)

  8. Assessment of radiation shielding materials for protection of space crews using CR-39 plastic nuclear track detector

    International Nuclear Information System (INIS)

    DeWitt, J.M.; Benton, E.R.; Uchihori, Y.; Yasuda, N.; Benton, E.V.; Frank, A.L.

    2009-01-01

    A significant obstacle to long duration human space exploration such as the establishment of a permanent base on the surface of the Moon or a human mission to Mars is the risk posed by prolonged exposure to space radiation. In order to keep mission costs at acceptable levels while simultaneously minimizing the risk from radiation to space crew health and safety, a judicious use of optimized shielding materials will be required. We have undertaken a comprehensive study using CR-39 plastic nuclear track detector (PNTD) to characterize the radiation shielding properties of a range of materials-both common baseline materials such as Al and polyethylene, and novel multifunctional materials such as carbon composites-at heavy ion accelerators. The study consists of analyzing CR-39 PNTD exposed in front of and behind shielding targets of varying composition and at a number of depths (target thicknesses) relevant to the development and testing of materials for space radiation shielding. Most targets consist of 10 cm x 10 cm slabs of solid materials ranging in thickness from 1 to >30 g/cm 2 . Exposures have been made to beams of C, O, Ne, Si, Ar, and Fe at energies ranging from 290 MeV/amu to 1 GeV/amu at the National Institute of Radiological Sciences HIMAC and the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory. Analysis of the exposed detectors yields LET spectrum, dose, and dose equivalent as functions of target depth and composition, and incident heavy ion charge, energy, and fluence. Efforts are currently underway to properly weigh and combine these results into a single quantitative estimate of a material's ability to shield space crews from the interplanetary galactic cosmic ray flux.

  9. Analysis of changes in environmental radiation, and three types of environmental radiation detector performance comparisons

    International Nuclear Information System (INIS)

    Park, J.H; Seo, J.H; Park, S.M; Yu, B.N; Park, J.H; Joo, K.S

    2013-06-01

    High-pressure ion chamber (GE Reuter-Stokes, HPIC), accuracy is high but the high price and do not have the ability nuclide analysis is a disadvantage. NaI(Tl) and PMT scintillation detector of radioactive materials can be divided. Environmental radiation measurements using a semiconductor with SiPM detector PMT to replace the value of the results were compared. SiPM detector using radiation environment were measured in the field to verify the accuracy and energy resolution. SiPMs performance as environmental radiation measurement equipment and radioactive material distinction as a personal dosimeter based technology, using the above results were prepared. The interest on the environmental radiation due to the Fukushima power plant crisis in Japan has been growing concern about the radiation environment of the relatively close proximity Korea is a very heightened state. Could be confirmed in the radiation environment of nuclear power plants around the analysis and performance of the next generation of environmental radiation meter. Fukushima power plants accident after 2 years, the equipment installed by this analysis meets the performance as a radiation detector could be confirmed as follows. CANA Inc. developed by radionuclides classification of using man-made and natural radionuclides and man-made radionuclides separated, ensure the value of the results were analyzed. Could be and alternative to the conventional detector energy resolution ( 137 CS<15%) and linearity (<15%) to satisfy the performance requirements of the measurement result of environmental radiation detector is considered. SiPM radiation environment changes and HPIC and NaI(TI) scintillation detector installed in Korea of the Fukushima power plant after the accident, radiation environment using a small alternative was to verify the accuracy of the measuring equipment. A big difference in performance as invisible by comparison with the large detector Assay miniaturization rough as a personal

  10. Department of Radiation Detectors: Overview

    International Nuclear Information System (INIS)

    Piekoszewski, J.

    1999-01-01

    Full text: Work carried out in 1998 in the Department of Radiation Detectors concentrated on three subjects: (i) Semiconductor Detectors (ii) X-ray Tube Generators (iii) Material Modification Using Ion and Plasma Beams. SEMICONDUCTOR DETECTORS: Semiconductor detectors of ionizing radiation are among the basic tools utilized in such fields of research and industry as nuclear physics, high energy physics, medical (oncology) radiotherapy, radiological protection, environmental monitoring, energy dispersive X-ray fluorescence non-destructive analysis of chemical composition, nuclear power industry. The departmental objectives are: a search for new types of detectors; producing unique detectors tailored for physics experiments; manufacturing standard detectors for radiation measuring instruments; scientific development of the staff. These objectives were accomplished in 1998 particularly by: research on unique thin silicon detectors for identification of particles in E-ΔE telescopes, modernization of technology of manufacturing Ge(Li) detectors capable of detecting broader range of gamma energies, manufacturing detectors developed in previous years, re-generating and servicing customer detectors of various origin. In accomplishment of the above the Department co-operated with groups of physicists from IPJ, PAN Institute of Physics (Warsaw), and with some technology Institutes based in Warsaw (ITME, ITE). Some detectors and services have been delivered to customers on a commercial basis. X-Ray TUBE GENERATORS: The Department conducts research on design and technology of manufacturing X-ray generators as well as on imaging and dosimetry of X-ray beams. Various models of special construction X-ray tubes and their power supplies are under construction. In 1998 work concentrated on: completing laboratory equipment for manufacturing X-ray tubes and their components, developing technology of manufacturing X-ray tubes and their components, completing a laboratory set-up with

  11. Solid-state radiation detectors technology and applications

    CERN Document Server

    2015-01-01

    The book discusses the current solid state material used in advance detectors manufacturing and their pros and cons and how one can tailor them using different techniques, to get the maximum performance. The book is application oriented to radiation detectors for medical, X and gamma rays application, and good reference with in-depth discussion of detector's physics as it relates to medical application tailored for engineers and scientists.

  12. Status and trends of solid state track detector use in radiation protection monitoring

    International Nuclear Information System (INIS)

    Doerschel, B.

    1980-01-01

    The characteristic properties of solid state track detectors allow them to be used for determining the radiation fields of charged and uncharged particles and, consequently, for solving some problems involved in radiation protection monitoring. Aptitude of various detector materials is investigated on the basis of the track formation mechanism taking into account the properties of the particles to be detected. Use of these detectors in radiation protection monitoring presumes appropriate methods of intensifying the latent tracks, which are discussed as a function of various physical parameters. Readout methods of solid state track detectors are based on variations in detector properties determined by number and size of particle tracks in the detector. The choice of a special readout method, among other things, depends on the purpose, detector material, and pretreatment of the detectors. The most prospective methods are described and investigated with respect to their possible use in various fields of radiation protection monitoring. The trends of development of the application of solid state track detectors in radiation protection monitoring are discussed, using some typical applications as examples. (author)

  13. Radiation-hard semiconductor detectors for SuperLHC

    CERN Document Server

    Bruzzi, Mara; Al-Ajili, A A; Alexandrov, P; Alfieri, G; Allport, Philip P; Andreazza, A; Artuso, M; Assouak, S; Avset, B S; Barabash, L; Baranova, E; Barcz, A; Basile, A; Bates, R; Belova, N; Betta, G F D; Biagi, S F; Bilei, G M; Bisello, D; Blue, A; Blumenau, A; Boisvert, V; Bölla, G; Bondarenko, G B; Borchi, E; Borrello, L; Bortoletto, D; Boscardin, M; Bosisio, L; Bowcock, T J V; Brodbeck, T J; Broz, J; Brukhanov, A; Brzozowski, A; Buda, M; Buhmann, P; Buttar, C; Campabadal, F; Campbell, D; Candelori, A; Casse, G; Cavallini, A; Chilingarov, A G; Chren, D; Cindro, V; Citterio, M; Collins, P; Coluccia, R; Contarato, D; Coutinho, J; Creanza, D; Cunningham, W; Cvetkov, V; Davies, G; Dawson, I; De Palma, M; Demina, R; Dervan, P; Dierlamm, A; Dittongo, S; Dobrzanski, L; Dolezal, Z; Dolgolenko, A; Eberlein, T; Eremin, V; Fall, C; Fasolo, F; Ferbel, T; Fizzotti, F; Fleta, C; Focardi, E; Forton, E; Franchenko, S; Fretwurst, E; Gamaz, F; García-Navarro, J E; García, C; Gaubas, E; Genest, M H; Gill, K A; Giolo, K; Glaser, M; Gössling, C; Golovine, V; Gorelov, I; Goss, J; Gouldwell, A; Grégoire, G; Gregori, P; Grigoriev, E; Grigson, C; Grillo, A; Groza, A; Guskov, J; Haddad, L; Harding, R; Härkönen, J; Hauler, F; Hayama, S; Hoeferkamp, M; Honniger, F; Horazdovsky, T; Horisberger, R P; Horn, M; Houdayer, A; Hourahine, B; Hruban, A; Hughes, G; Ilyashenko, Yu S; Irmscher, K; Ivanov, A; Jarasiunas, K; Jin, T; Jones, B K; Jones, R; Joram, C; Jungermann, L; Kalinina, E; Kaminski, P; Karpenko, A; Karpov, A; Kazlauskiene, V; Kazukauskas, V; Khivrich, V; Khomenkov, V P; Kierstead, J A; Klaiber Lodewigs, J M; Kleverman, M; Klingenberg, R; Kodys, P; Kohout, Z; Korjenevski, S; Kowalik, A; Kozlowski, R; Kozodaev, M; Kramberger, G; Krasel, O; Kuznetsov, A; Kwan, S; Lagomarsino, S; Lari, T; Lassila-Perini, K M; Lastovetsky, V F; Latino, G; Latushkin, S T; Lazanu, I; Lazanu, S; Lebel, C; Leinonen, K; Leroy, C; Li, Z; Lindström, G; Lindström, L; Linhart, V; Litovchenko, A P; Litovchenko, P G; Litvinov, V; Lo Giudice, A; Lozano, M; Luczynski, Z; Luukka, Panja; Macchiolo, A; Mainwood, A; Makarenko, L F; Mandic, I; Manfredotti, C; Martí i García, S; Marunko, S; Mathieson, K; Melone, J; Menichelli, D; Meroni, C; Messineo, A; Miglio, S; Mikuz, M; Miyamoto, J; Moll, M; Monakhov, E; Moscatelli, F; Mozzanti, A; Murin, L; Naoumov, D; Nava, F; Nossarzhevska, E; Nummela, S; Nysten, J; Olivero, P; O'Shea, V; Palviainen, T; Paolini, C; Parkes, C; Passeri, D; Pein, U; Pellegrini, G; Perera, L; Petasecca, M; Piatkowski, B; Piemonte, C; Pignatel, G U; Pinho, N; Pintilie, I; Pintilie, L; Polivtsev, L; Polozov, P; Popa, A I; Popule, J; Pospísil, S; Pucker, G; Radicci, V; Rafí, J M; Ragusa, F; Rahman, M; Rando, R; Röder, R; Rohe, T; Ronchin, S; Rott, C; Roy, A; Roy, P; Ruzin, A; Ryazanov, A; Sadrozinski, H F W; Sakalauskas, S; Scaringella, M; Schiavulli, L; Schnetzer, S; Schumm, B; Sciortino, S; Scorzoni, A; Segneri, G; Seidel, S; Seiden, A; Sellberg, G; Sellin, P J; Sentenac, D; Sevilla, S G; Shipsey, I; Sícho, P; Sloan, T; Solar, M; Son, S; Sopko, B; Spencer, N; Stahl, J; Stavitski, I; Stolze, D; Stone, R; Storasta, J; Strokan, N; Strupinski, W; Sudzius, M; Surma, B; Suuronen, J; Suvorov, A; Svensson, B G; Tipton, P; Tomasek, M; Troncon, C; Tsvetkov, A; Tuominen, E; Tuovinen, E; Tuuva, T; Tylchin, M; Uebersee, H; Uher, J; Ullán, M; Vaitkus, J V; Vanni, P; Velthuis, J; Verbitskaya, E; Verzellesi, G; Vrba, V; Wagner, G; Wilhelm, I; Worm, S; Wright, V; Wunstorf, R; Zabierowski, P; Zaluzhny, A; Zavrtanik, M; Zen, M; Zhukov, V; Zorzi, N; de Boer, Wim

    2005-01-01

    An option of increasing the luminosity of the Large Hadron Collider (LHC) at CERN to 10/sup 35/ cm-/sup 2/s-/sup 1/ has been envisaged to extend the physics reach of the machine. An efficient tracking down to a few centimetres from the interaction point will be required to exploit the physics potential of the upgraded LHC. As a consequence, the semiconductor detectors close to the interaction region will receive severe doses of fast hadron irradiation and the inner tracker detectors will need to survive fast hadron fluences of up to above 10 /sup 16/ cm-/sup 2/. The CERN-RD50 project "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" has been established in 2002 to explore detector materials and technologies that will allow to operate devices up to, or beyond, this limit. The strategies followed by RD50 to enhance the radiation tolerance include the development of new or defect engineered detector materials (SiC, GaN, Czochralski and epitaxial silicon, oxygen enriched Flo...

  14. Development of CVD diamond radiation detectors

    CERN Document Server

    Adam, W; Berdermann, E; Bogani, F; Borchi, E; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fisch, D; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E A; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Knöpfle, K T; Krammer, Manfred; Manfredi, P F; Meier, D; Mishina, M; Le Normand, F; Pan, L S; Pernegger, H; Pernicka, Manfred; Pirollo, S; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Tapper, R J; Tesarek, R J; Thomson, G B; Trawick, M L; Trischuk, W; Turchetta, R; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zoeller, M M

    1998-01-01

    Diamond is a nearly ideal material for detecting ionizing radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow a diamond detector to be used in high ra diation, high temperature and in aggressive chemical media. We have constructed charged particle detectors using high quality CVD diamond. Characterization of the diamond samples and various detect ors are presented in terms of collection distance, $d=\\mu E \\tau$, the average distance electron-hole pairs move apart under the influence of an electric field, where $\\mu$ is the sum of carrier mo bilities, $E$ is the applied electric field, and $\\tau$ is the mobility weighted carrier lifetime. Over the last two years the collection distance increased from $\\sim$ 75 $\\mu$m to over 200 $\\mu$ m. With this high quality CVD diamond a series of micro-strip and pixel particle detectors have been constructed. These devices were tested to determine their position resolution and signal to n oise performance. Diamond detectors w...

  15. Radiation damage resistance in mercuric iodide X-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Patt, B E; Dolin, R C; Devore, T M; Markakis, J M [EG and G Energy Measurements, Inc., Goleta, CA (USA); Iwanczyk, J S; Dorri, N [Xsirius, Inc., Marina del Rey, CA (USA); Trombka, J [National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center

    1990-12-20

    Mercuric iodide (HgI{sub 2}) radiation detectors show great potential as ambient-temperature solid-state detectors for X-rays, gamma rays and visible light, with parameters that are competitive with existing technologies. In a previous experiment, HgI{sub 2} detectors irradiated with 10 MeV protons/cm{sup 2} exhibited no damage. The 10 MeV protons represent only the low range of the spectrum of energies that are important. An experiment has been conducted at the Saturne accelerator facility at Saclay, France, to determine the susceptibility of these detectors to radiation damage by high-energy (1.5 GeV) protons. The detectors were irradiated to a fluence of 10{sup 8} protons/cm{sup 2}. This fluence is equivalent to the cosmic radiation expected in a one-year period in space. The resolution of the detectors was measured as a function of the integral dose. No degradation in the response of any of the detectors or spectrometers was seen. It is clear from this data that HgI{sub 2} has extremely high radiation-damage resistance, exceeding that of most other semiconductor materials used for radiation detectors. Based on the results shown to date, HgI{sub 2} detectors are suitable for applications in which they may be exposed to high integral dose levels. (orig.).

  16. High energy radiation detector

    International Nuclear Information System (INIS)

    Vosburgh, K.G.

    1975-01-01

    The high energy radiation detector described comprises a set of closely spaced wedge reflectors. Each wedge reflector is composed of three sides forming identical isoceles triangles with a common apex and an open base forming an equilateral triangle. The length of one side of the base is less than the thickness of the coat of material sensitive to high energy radiation. The wedge reflectors reflect the light photons spreading to the rear of the coat in such a way that each reflected track is parallel to the incident track of the light photon spreading rearwards. The angle of the three isosceles triangles with a common apex is between 85 and 95 deg. The first main surface of the coat of high energy radiation sensitive material is in contact with the projecting edges of the surface of the wedge reflectors of the reflecting element [fr

  17. Foam radiators for transition radiation detectors

    International Nuclear Information System (INIS)

    Chernyatin, V.; Dolgoshein, B.; Gavrilenko, I.; Potekhin, M.; Romaniouk, A.; Sosnovtsev, V.

    1993-01-01

    A wide variety of foam radiators, potentially useful in the design of a transition radiation detector, the possible particle identification tool in collider experiments, have been tested in the beam. Various characteristics of these radiators are compared, and the conclusion is reached that certain brands of polyethylene foam are best suited for use in the detector. Comparison is made with a 'traditional' radiator, which is a periodic structure of plastic foils. (orig.)

  18. Department of Radiation Detectors - Overview

    International Nuclear Information System (INIS)

    Piekoszewski, J.

    1997-01-01

    Work carried out in 1996 in the Department of Radiation Detectors concentrated on three subjects: (i) Semiconductor Detectors (ii) X-ray Tube Generators (iii) Material Modification Using Ion and Plasma Beams. The Departamental objectives are: a search for new types of detectors, adapting modern technologies (especially of industrial microelectronics) to detector manufacturing, producing unique detectors tailored for physics experiments, manufacturing standard detectors for radiation measuring instruments. These objectives were accomplished in 1996 by: research on unique detectors for nuclear physics (e.g. a spherical set of particle detectors silicon ball), detectors for particle identification), development of technology of high-resistivity silicon detectors HRSi (grant proposal), development of thermoelectric cooling systems (grant proposal), research on p-i-n photodiode-based personal dosimeters, study of applicability of industrial planar technology in producing detectors, manufacturing detectors developed in previous years, re-generating and servicing customer detectors of various origin. The Department conducts research on the design and technology involved in producing X-ray generators based on X-ray tubes of special construction. Various tube models and their power supplies were developed. Some work has also been devoted to the detection and dosimetry of X-rays. X-ray tube generators are applied to non-destructive testing and are components of analytical systems such as: X-ray fluorescence chemical composition analysis, gauges of layer thickness and composition stress measurements, on-line control of processes, others where an X-ray tube may replace a radio-isotope source. In 1996, the Department: reviewed the domestic demand for X-ray generators, developed an X-ray generator for diagnosis of ostheroporosis of human limbs, prepared a grant proposal for the development of a new instrument for radiotherapy, the so-called needle-like X-ray tube. (author)

  19. Department of Radiation Detectors - Overview

    Energy Technology Data Exchange (ETDEWEB)

    Piekoszewski, J. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)

    1997-12-31

    Work carried out in 1996 in the Department of Radiation Detectors concentrated on three subjects: (i) Semiconductor Detectors (ii) X-ray Tube Generators (iii) Material Modification Using Ion and Plasma Beams. The Departamental objectives are: a search for new types of detectors, adapting modern technologies (especially of industrial microelectronics) to detector manufacturing, producing unique detectors tailored for physics experiments, manufacturing standard detectors for radiation measuring instruments. These objectives were accomplished in 1996 by: research on unique detectors for nuclear physics (e.g. a spherical set of particle detectors silicon ball), detectors for particle identification), development of technology of high-resistivity silicon detectors HRSi (grant proposal), development of thermoelectric cooling systems (grant proposal), research on p-i-n photodiode-based personal dosimeters, study of applicability of industrial planar technology in producing detectors, manufacturing detectors developed in previous years, re-generating and servicing customer detectors of various origin. The Department conducts research on the design and technology involved in producing X-ray generators based on X-ray tubes of special construction. Various tube models and their power supplies were developed. Some work has also been devoted to the detection and dosimetry of X-rays. X-ray tube generators are applied to non-destructive testing and are components of analytical systems such as: X-ray fluorescence chemical composition analysis, gauges of layer thickness and composition stress measurements, on-line control of processes, others where an X-ray tube may replace a radio-isotope source. In 1996, the Department: reviewed the domestic demand for X-ray generators, developed an X-ray generator for diagnosis of ostheroporosis of human limbs, prepared a grant proposal for the development of a new instrument for radiotherapy, the so-called needle-like X-ray tube. (author).

  20. Isotope detectors and radiation detectors for test reliability techniqui. A preliminary project

    International Nuclear Information System (INIS)

    Christell, R.

    1977-03-01

    A survey is done of small and simple components for use as detectors for ionizing radiation, as well as different methods and components producing images of radiation fields based on position sensitive detectors. The investigation has resulted in a system for detection of stones in wood. In a second project isotope excited x ray fluorescence has been used for analysis of material resulting from wear of mechanical components. A facility for analysis has been built and test analysis has been performed. Methods for continous wear control with possibility to forecast breakdowns have been investigated. (K.K.)

  1. Organic materials and devices for detecting ionizing radiation

    Science.gov (United States)

    Doty, F Patrick [Livermore, CA; Chinn, Douglas A [Livermore, CA

    2007-03-06

    A .pi.-conjugated organic material for detecting ionizing radiation, and particularly for detecting low energy fission neutrons. The .pi.-conjugated materials comprise a class of organic materials whose members are intrinsic semiconducting materials. Included in this class are .pi.-conjugated polymers, polyaromatic hydrocarbon molecules, and quinolates. Because of their high resistivities (.gtoreq.10.sup.9 ohmcm), these .pi.-conjugated organic materials exhibit very low leakage currents. A device for detecting and measuring ionizing radiation can be made by applying an electric field to a layer of the .pi.-conjugated polymer material to measure electron/hole pair formation. A layer of the .pi.-conjugated polymer material can be made by conventional polymer fabrication methods and can be cast into sheets capable of covering large areas. These sheets of polymer radiation detector material can be deposited between flexible electrodes and rolled up to form a radiation detector occupying a small volume but having a large surface area. The semiconducting polymer material can be easily fabricated in layers about 10 .mu.m to 100 .mu.m thick. These thin polymer layers and their associated electrodes can be stacked to form unique multi-layer detector arrangements that occupy small volume.

  2. Advanced Space Radiation Detector Technology Development

    Science.gov (United States)

    Wrbanek, John D.; Wrbanek, Susan Y.; Fralick, Gustave C.

    2013-01-01

    The advanced space radiation detector development team at the NASA Glenn Research Center (GRC) has the goal of developing unique, more compact radiation detectors that provide improved real-time data on space radiation. The team has performed studies of different detector designs using a variety of combinations of solid-state detectors, which allow higher sensitivity to radiation in a smaller package and operate at lower voltage than traditional detectors. Integration of multiple solid-state detectors will result in an improved detector system in comparison to existing state-of-the-art instruments for the detection and monitoring of the space radiation field for deep space and aerospace applications.

  3. RD50 Collaboration overview: Development of new radiation hard detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, S., E-mail: susanne.kuehn@cern.ch

    2016-07-11

    Silicon sensors are widely used as tracking detectors in high energy physics experiments. This results in several specific requirements like radiation hardness and granularity. Therefore research for highly performing silicon detectors is required. The RD50 Collaboration is a CERN R&D collaboration dedicated to the development of radiation hard silicon devices for application in high luminosity collider experiments. Extensive research is ongoing in different fields since 2001. The collaboration investigates both defect and material characterization, detector characterization, the development of new structures and full detector systems. The report gives selected results of the collaboration and places an emphasis on the development of new structures, namely 3D devices, CMOS sensors in HV technology and low gain avalanche detectors. - Highlights: • The RD50 Collaboration is a CERN R&D collaboration dedicated to the development of radiation hard silicon devices for high luminosity collider experiments. • The collaboration investigates defect, material and detector characterization, the development of new structures and full detector systems. • Results of measured data of n-in-p type sensors allow recommendations for silicon tracking detectors at the HL-LHC. • The charge multiplication effect was investigated to allow its exploitation and resulted in new structures like LGAD sensors. • New sensor types like slim and active edge sensors, 3D detectors, and lately HVCMOS devices were developed in the active collaboration.

  4. Silicon radiation detectors

    International Nuclear Information System (INIS)

    Lutz, G.

    1995-01-01

    An introduction to and an overview of function principles and properties of semiconductor radiation detectors is attempted. The paper is addressed to people interested in detector development but not already experts in the field of semiconductor detectors. (orig.)

  5. The radiation environment in the ATLAS inner detector

    CERN Document Server

    Dawson, I

    2000-01-01

    The radiation environment in the inner detector has been simulated using the particle transport program FLUKA with a recent description of the ATLAS experiment. Given in this paper are particle fluences and doses at positions relevant to the three inner detector subsystems; the Pixel, SCT and TRT detectors. In addition, studies are reported on in which (1) information concerning the optimization of the inner detector neutron-moderators is obtained and (2) the impact of including additional vacuum-equipment material is assessed. (19 refs).

  6. Radiation damage study in CZT matrix detectors exposed to gamma rays

    International Nuclear Information System (INIS)

    Leyva Fabelo, Antonio; Pinnera Hernandez, Ibrahin; Cruz Inclan, Carlos Manuel; Abreu Alfonso, Yamiel; Dona Lemus, Olga; Diaz Garcia, Angelina; Montanno Zetina, Luis Manuel

    2009-01-01

    Radiation damage in terms of atomic displacements in a typical CZT detector used in medical imaging applications was studied using the Monte Carlo statistical method. All detector structural and geometric features as well as different energies of the photons usually used in the application were taken into account. Considering the Mott McKinley Feshbach classical approach, effective cross sections of the displacements were calculated, including the number of displacements per atom for each atomic species present in the material and each photon energy considered. These results are analyzed and compared. Finally, the radiation damage on CZT detector is compared to that calculated in a similar detector manufactured with other semiconducting materials. (author)

  7. Metal-semiconductor, composite radiation detectors

    International Nuclear Information System (INIS)

    Orvis, W.J.; Yee, J.H.; Fuess, D.A.

    1991-12-01

    In 1989, Naruse and Hatayama of Toshiba published a design for an increased efficiency x-ray detector. The design increased the efficiency of a semiconductor detector by interspersing layers of high-z metal within it. Semiconductors such as silicon make good, high-resolution radiation detectors, but they have low efficiency because they are low-z materials (z = 14). High-z metals, on the other hand, are good absorbers of high-energy photons. By interspersing high-z metal layers with semiconductor layers, Naruse and Hatayama combined the high absorption efficiency of the high-z metals with good detection capabilities of a semiconductor. This project is an attempt to use the same design to produce a high- efficiency gamma ray detector. By their nature, gamma rays require thicker metal layers to efficiently absorb them. These thicker layers change the behavior of the detector by reducing the resolution, compared to a solid state detector, and shifting the photopeak by a predictable amount. During the last year, we have modeled parts of the detector and have nearly completed a prototype device. 2 refs

  8. Low radioactivity material for use in mounting radiation detectors

    Science.gov (United States)

    Fong, Marshall; Metzger, Albert E.; Fox, Richard L.

    1988-01-01

    Two materials, sapphire and synthetic quartz, have been found for use in Ge detector mounting assemblies. These materials combine desirable mechanical, thermal, and electrical properties with the radioactive cleanliness required to detect minimal amounts of K, Th, and U.

  9. Radiation effects in polymers for plastic scintillation detectors

    International Nuclear Information System (INIS)

    Pla-Dalmau, A.; Bross, A.D.; Hurlbut, C.R.; Moser, S.W.

    1994-01-01

    Recent developments in both scintillating plastic optical fibers and photon detection devices have spawned new applications for plastic scintillator detectors. This renewed attention has encouraged research that addresses the radiation stability of plastic scintillators. The optical quality of the polymer degrades with exposure to ionizing radiation and thus the light yield of the detector decreases. A complete understanding of all the mechanisms contributing to this radiation-induced degradation of the polymer can lead to techniques that will extend the radiation stability of these materials. Various radiation damage studies have been performed under different atmospheres and dose rates. Currently, the use of additives to preserve the optical properties of the polymer matrix under radiation is being investigated. The authors discuss the effect of certain antioxidants, plasticizers, and cross-linking agents on the radiation resilience of plastic scintillators

  10. 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)

  11. Metal-semiconductor, composite radiation detectors

    International Nuclear Information System (INIS)

    Orvis, W.J.; Yee, J.H.; Fuess, D.

    1992-12-01

    In 1989, Naruse and Hatayama of Toshiba published a design for an increased efficiency x-ray detector. The design increased the efficiency of a semiconductor detector by interspersing layers of high-z metal within it. Semiconductors such as silicon make good, high-resolution radiation detectors, but they have low efficiency because they are low-z materials (z = 14). High-z metals, on the other hand, are good absorbers of high-energy photons. By interspersing high-z metal layers with semiconductor layers, Naruse and Hatayama combined the high absorption efficiency of the high-z metals with the good detection capabilities of a semiconductor. This project is an attempt to use the same design to produce a high-efficiency, room temperature gamma ray detector. By their nature, gamma rays require thicker metal layers to efficiently absorb them. These thicker layers change the behavior of the detector by reducing the resolution, compared to a solid state detector, and shifting the photopeak by a predictable amount. During the last year, the authors have procured and tested a commercial device with operating characteristics similar to those of a single layer of the composite device. They have modeled the radiation transport in a multi-layered device, to verify the initial calculations of layer thickness and composition. They have modeled the electrostatic field in different device designs to locate and remove high-field regions that can cause device breakdown. They have fabricated 14 single layer prototypes

  12. Portable radiation detector and mapping system

    International Nuclear Information System (INIS)

    Hofstetter, K.J.; Hayes, D.W.; Eakle, R.F.

    1995-01-01

    A portable radiation detector and mapping system (RADMAPS) has been developed to detect, locate and plot nuclear radiation intensities on commercially available digital maps and other images. The field unit records gamma-ray spectra or neutron signals together with positions from a Global Positioning System (GPS) on flash memory cards. The recorded information is then transferred to a lap-top computer for spectral data analyses and then georegistered graphically on maps, photographs, etc. RADMAPS integrates several existing technologies to produce a preprogrammable field unit uniquely suited for each survey, as required. The system presently records spectra from a Nal(Tl) gamma-ray detector or an enriched Li-6 doped glass neutron scintillator. Standard Geographic Information System software installed in a lap-top, complete with CD-ROM supporting digitally imaged maps, permits the characterization of nuclear material in the field when the presence of such material is not otherwise documented. This paper gives the results of a typical site survey of the Savannah River Site (SRS) using RADMAPS

  13. Assessment of integrated solar ultraviolet radiation by PM-355 detectors

    International Nuclear Information System (INIS)

    Abu-Jarad, F.; Al-Jarallah, M.I.; Elhadidy, M.A.; Shaahid, S.M.; Fazal-ur-Rehman

    2000-01-01

    The increase in environmental solar UV radiation due to depletion of ozone layer is a recent challenge to human health (skin cancer and eye effects) in countries having clear skies. Therefore, applying integrated, passive and inexpensive techniques to assess solar UV radiation is very much essential. Measurements of environmental solar UV radiation in Dhahran, Saudi Arabia area were carried out for a period of two months in the summer period in 1996 using two techniques in parallel namely: passive nuclear track detectors and active solar UV radiometers. Some of the nuclear track detectors were mounted in different conditions such as: under shadow band, on solar tracking mechanism following the solar rays. Others were mounted on perpendicular, tilted and horizontal surfaces in sunlight. All detectors were attached to a wooden background of the same thickness (0.5 cm) to eliminate interference of the heat effect of various support materials and have uniformity of the support materials. The assessment was carried out for different periods extending from two to nine weeks continuously. The investigated period covered the hottest months in Saudi Arabia (July and August) when the sky was clear of clouds. The results indicate linear correlation between alpha track diameters and the integrated exposure to solar UV as measured by the solar UV radiometer for all nuclear track detector positions and orientations. The highest slope has been observed for the detectors placed on solar tracking mechanism following the solar rays and the lowest from detectors oriented under the shadow band on horizontal position (measuring the diffused UV radiation only). The results show that most of the measured UV radiation (60%) were from the diffused UV radiation. The characteristics of the upper layer of the detectors are changed after chemical etching very quickly, with increase in the exposure time to UV solar radiation at certain orientation. The results encourage the use of nuclear track

  14. Assessment of integrated solar ultraviolet radiation by PM-355 detectors

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Al-Jarallah, M.I.; Elhadidy, M.A.; Shaahid, S.M.; Fazal-ur-Rehman

    2000-06-01

    The increase in environmental solar UV radiation due to depletion of ozone layer is a recent challenge to human health (skin cancer and eye effects) in countries having clear skies. Therefore, applying integrated, passive and inexpensive techniques to assess solar UV radiation is very much essential. Measurements of environmental solar UV radiation in Dhahran, Saudi Arabia area were carried out for a period of two months in the summer period in 1996 using two techniques in parallel namely: passive nuclear track detectors and active solar UV radiometers. Some of the nuclear track detectors were mounted in different conditions such as: under shadow band, on solar tracking mechanism following the solar rays. Others were mounted on perpendicular, tilted and horizontal surfaces in sunlight. All detectors were attached to a wooden background of the same thickness (0.5 cm) to eliminate interference of the heat effect of various support materials and have uniformity of the support materials. The assessment was carried out for different periods extending from two to nine weeks continuously. The investigated period covered the hottest months in Saudi Arabia (July and August) when the sky was clear of clouds. The results indicate linear correlation between alpha track diameters and the integrated exposure to solar UV as measured by the solar UV radiometer for all nuclear track detector positions and orientations. The highest slope has been observed for the detectors placed on solar tracking mechanism following the solar rays and the lowest from detectors oriented under the shadow band on horizontal position (measuring the diffused UV radiation only). The results show that most of the measured UV radiation (60%) were from the diffused UV radiation. The characteristics of the upper layer of the detectors are changed after chemical etching very quickly, with increase in the exposure time to UV solar radiation at certain orientation. The results encourage the use of nuclear track

  15. Detection of gamma-neutron radiation by solid-state scintillation detectors. Detection of gamma-neutron radiation by novel solid-state scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ryzhikov, V.; Grinyov, B.; Piven, L.; Onyshchenko, G.; Sidletskiy, O. [Institute for Scintillation Materials of the NAS of Ukraine, Kharkov, (Ukraine); Naydenov, S. [Institute for Single Crystals of the National Academy of Sciences of Ukraine, Kharkov, (Ukraine); Pochet, T. [DETEC-Europe, Vannes (France); Smith, C. [Naval Postgraduate School, Monterey, CA (United States)

    2015-07-01

    It is known that solid-state scintillators can be used for detection of both gamma radiation and neutron flux. In the past, neutron detection efficiencies of such solid-state scintillators did not exceed 5-7%. At the same time it is known that the detection efficiency of the gamma-neutron radiation characteristic of nuclear fissionable materials is by an order of magnitude higher than the efficiency of detection of neutron fluxes alone. Thus, an important objective is the creation of detection systems that are both highly efficient in gamma-neutron detection and also capable of exhibiting high gamma suppression for use in the role of detection of neutron radiation. In this work, we present the results of our experimental and theoretical studies on the detection efficiency of fast neutrons from a {sup 239}Pu-Be source by the heavy oxide scintillators BGO, GSO, CWO and ZWO, as well as ZnSe(Te, O). The most probable mechanism of fast neutron interaction with nuclei of heavy oxide scintillators is the inelastic scattering (n, n'γ) reaction. In our work, fast neutron detection efficiencies were determined by the method of internal counting of gamma-quanta that emerge in the scintillator from (n, n''γ) reactions on scintillator nuclei with the resulting gamma energies of ∼20-300 keV. The measured efficiency of neutron detection for the scintillation crystals we considered was ∼40-50 %. The present work included a detailed analysis of detection efficiency as a function of detector and area of the working surface, as well as a search for new ways to create larger-sized detectors of lower cost. As a result of our studies, we have found an unusual dependence of fast neutron detection efficiency upon thickness of the oxide scintillators. An explanation for this anomaly may involve the competition of two factors that accompany inelastic scattering on the heavy atomic nuclei. The transformation of the energy spectrum of neutrons involved in the (n, n

  16. Semiconductor neutron detectors based on new types of materials

    International Nuclear Information System (INIS)

    Pochet, T.; Foulon, F.

    1993-01-01

    Neutron detection in hostile environments such as nuclear reactors has been performed using a new kind of semiconductor detector. So far, crystalline semiconductor detectors are not used in nuclear reactor instrumentation because of their sensitivity to radiation damage. For doses in excess of a few tens of kilo rads, radiation induced lattice defects produce a strong loss in the standard semiconductor detector performances. In the last few years, new semiconductor materials having amorphous or polycrystalline structures such as silicon, silicon carbide or CVD diamond, became available. These semiconductors, produced by Chemical Vapor Deposition, come in the form of thin layers being typically a few tens of micron thick. Their crystalline structure is particularly resistant to radiation damage up to a few Mrads but prevent the material use in spectrometry measurements. Nevertheless, these detectors, working in a counting mode, are suitable for the detection of alpha particles produced by the neutron capture reaction with boron. Such thin film detectors have a very poor sensitivity to γ-ray background. Furthermore, they are easier and cheaper to implement than current neutron gas counters. Preliminary results obtained with diamond and amorphous silicon diodes exposed to α particles are presented. (authors). 7 figs., 3 tabs., 11 refs

  17. Basic Radiation Detectors. Chapter 6

    Energy Technology Data Exchange (ETDEWEB)

    Van Eijk, C. W.E. [Faculty of Applied Sciences, Delft University of Technology, Delft (Netherlands)

    2014-12-15

    Radiation detectors are of paramount importance in nuclear medicine. The detectors provide a wide range of information including the radiation dose of a laboratory worker and the positron emission tomography (PET) image of a patient. Consequently, detectors with strongly differing specifications are used. In this chapter, general aspects of detectors are discussed.

  18. Spectral Analysis Method of Plastic Scintillator-based Radiation Detector against Nuclear/Radiological Terrorism

    International Nuclear Information System (INIS)

    Kwak, Sung-Woo; Yoo, Ho-Sik; Jang, Sung Soon; Kim, Jung-Soo; Yoon, Wan-Ki

    2008-01-01

    In these days, the threats relating to nuclear or radioactive materials have become a matter of internationally increased grave concern. A plastic scintillation detector in radiation portal monitoring (RPM) application has been used to detect radioactive sources in steel scrap entering reprocessing facilities, and to detect illicit transport of radioactive material across border ports-of-entry. The detection systems for RPM application usually are large and can not easily be moved to a different location. For some situations, an inconspicuous and mobile system for the radioactive or nuclear material during road transport is needed. The mobile radiation detection system has employed a NaI- based radiation detector to detect and identify the material hidden in vehicle. There are some operational constraints - short measuring time, weak activity due to heavy shield of illegal source, long distance - of inspection system in such nuclear security applications. Due to these constraints, large area sensor is required to maximize its sensitivity. Large NaI material, however, is extremely expensive. In designing a radiation detector for prevention of illicit trafficking of nuclear or radioactive materials, the trade-off should be carefully optimized between performance and cost in order to achieve cost-effective inspection system. For the cost-effective mobile radiation detection system, this paper describes new spectral analysis method to use the crude spectroscopic information available from a plastic detector to discriminate other man-made radiation source from NORM

  19. Domestic smoke detectors using radioactive material

    International Nuclear Information System (INIS)

    Anon.

    1979-02-01

    Increasing numbers of technical and consumer products incorporating radioactive material are becoming available to the Australian public. One consumer device of this type coming into common use is the domestic smoke detector that uses Americium 241 in detecting smoke. This device has obvious life-saving and property-saving advantages and is attractive in that it is attractive in that it is self-contained, battery powered and needs little maintenance. The National Health and Medical Research Council in October 1978 recommended conditions, which are listed, are intended to ensure that radiation safety is preserved. They provide for the testing and approval of all models of domestic smoke detectors using radioactive material. The National Health and Medical Research Council stated that provided these conditions are applied it had no objection to the sale of these detectors by retailers

  20. Device for characterization of fissile materials comprising at least a neutron detector embedded inside a scintillator for gamma radiation detection

    International Nuclear Information System (INIS)

    Bernard, P.; Dherbey, J.R.; Bosser, R.; Berne, R.

    1989-01-01

    Fissile materials, for instance in radioactive wastes, are characterized by measurement of prompt and delayed neutrons and gamma radiation from induced fission by a neutron source. Gamma radiation is detected with a scintillation detector associated to a photomultiplier, the scintillation material is at the same time a moderator for thermalization of fast neutrons emitted by the neutron source and also of neutrons from spontaneous fission, (α, n) reactions and neutrons from induced fission in the fissile material. Preferentially the moderator is made of Altustipe (Plexiglas with anthracene as additive) [fr

  1. Investigation of epitaxial silicon layers as a material for radiation hardened silicon detectors

    International Nuclear Information System (INIS)

    Li, Z.; Eremin, V.; Ilyashenko, I.; Ivanov, A.; Verbitskaya, E.

    1997-12-01

    Epitaxial grown thick layers (≥ 100 micrometers) of high resistivity silicon (Epi-Si) have been investigated as a possible candidate of radiation hardened material for detectors for high-energy physics. As grown Epi-Si layers contain high concentration (up to 2 x 10 12 cm -3 ) of deep levels compared with that in standard high resistivity bulk Si. After irradiation of test diodes by protons (E p = 24 GeV) with a fluence of 1.5 x 10 11 cm -2 , no additional radiation induced deep traps have been detected. A reasonable explanation is that there is a sink of primary radiation induced defects (interstitial and vacancies), possibly by as-grown defects, in epitaxial layers. The ''sinking'' process, however, becomes non-effective at high radiation fluences (10 14 cm -2 ) due to saturation of epitaxial defects by high concentration of radiation induced ones. As a result, at neutron fluence of 1 x 10 14 cm -2 the deep level spectrum corresponds to well-known spectrum of radiation induced defects in high resistivity bulk Si. The net effective concentration in the space charge region equals to 3 x 10 12 cm -3 after 3 months of room temperature storage and reveals similar annealing behavior for epitaxial as compared to bulk silicon

  2. Radiation response issues for infrared detectors

    Science.gov (United States)

    Kalma, Arne H.

    1990-01-01

    Researchers describe the most important radiation response issues for infrared detectors. In general, the two key degradation mechanisms in infrared detectors are the noise produced by exposure to a flux of ionizing particles (e.g.; trapped electronics and protons, debris gammas and electrons, radioactive decay of neutron-activated materials) and permanent damage produced by exposure to total dose. Total-dose-induced damage is most often the result of charge trapping in insulators or at interfaces. Exposure to short pulses of ionization (e.g.; prompt x rays or gammas, delayed gammas) will cause detector upset. However, this upset is not important to a sensor unless the recovery time is too long. A few detector technologies are vulnerable to neutron-induced displacement damage, but fortunately most are not. Researchers compare the responses of the new technologies with those of the mainstream technologies of PV HgCdTe and IBC Si:As. One important reason for this comparison is to note where some of the newer technologies have the potential to provide significantly improved radiation hardness compared with that of the mainstream technologies, and thus to provide greater motivation for the pursuit of these technologies.

  3. Solid state radiation detector system

    International Nuclear Information System (INIS)

    1977-01-01

    A solid state radiation flux detector system utilizes a detector element, consisting of a bar of semiconductor having electrical conductance of magnitude dependent upon the magnitude of photon and charged particle flux impinging thereon, and negative feedback circuitry for adjusting the current flow through a light emitting diode to facilitate the addition of optical flux, having a magnitude decreasing in proportion to any increase in the magnitude of radiation (e.g. x-ray) flux incident upon the detector element, whereby the conductance of the detector element is maintained essentially constant. The light emitting diode also illuminates a photodiode to generate a detector output having a stable, highly linear response with time and incident radiation flux changes

  4. Superlattice electroabsorption radiation detector

    International Nuclear Information System (INIS)

    Cooke, B.J.

    1993-06-01

    This paper provides a preliminary investigation of a new class of superlattice electroabsorption radiation detectors that employ direct optical modulation for high-speed, two-dimensional (2-D), high-resolution imaging. Applications for the detector include nuclear radiation measurements, tactical guidance and detection (laser radar), inertial fusion plasma studies, and satellite-based sensors. Initial calculations discussed in this paper indicate that a 1.5-μm (GaAlAs) multi-quantum-well (MQW) Fabry-Perot detector can respond directly to radiation of energies 1 eV to 10 KeV, and indirectly (with scattering targets) up through gamma, with 2-D sample rates on the order of 20 ps

  5. Room Temperature Hard Radiation Detectors Based on Solid State Compound Semiconductors: An Overview

    Science.gov (United States)

    Mirzaei, Ali; Huh, Jeung-Soo; Kim, Sang Sub; Kim, Hyoun Woo

    2018-05-01

    Si and Ge single crystals are the most common semiconductor radiation detectors. However, they need to work at cryogenic temperatures to decrease their noise levels. In contrast, compound semiconductors can be operated at room temperature due to their ability to grow compound materials with tunable densities, band gaps and atomic numbers. Highly efficient room temperature hard radiation detectors can be utilized in biomedical diagnostics, nuclear safety and homeland security applications. In this review, we discuss room temperature compound semiconductors. Since the field of radiation detection is broad and a discussion of all compound materials for radiation sensing is impossible, we discuss the most important materials for the detection of hard radiation with a focus on binary heavy metal semiconductors and ternary and quaternary chalcogenide compounds.

  6. Room Temperature Hard Radiation Detectors Based on Solid State Compound Semiconductors: An Overview

    Science.gov (United States)

    Mirzaei, Ali; Huh, Jeung-Soo; Kim, Sang Sub; Kim, Hyoun Woo

    2018-03-01

    Si and Ge single crystals are the most common semiconductor radiation detectors. However, they need to work at cryogenic temperatures to decrease their noise levels. In contrast, compound semiconductors can be operated at room temperature due to their ability to grow compound materials with tunable densities, band gaps and atomic numbers. Highly efficient room temperature hard radiation detectors can be utilized in biomedical diagnostics, nuclear safety and homeland security applications. In this review, we discuss room temperature compound semiconductors. Since the field of radiation detection is broad and a discussion of all compound materials for radiation sensing is impossible, we discuss the most important materials for the detection of hard radiation with a focus on binary heavy metal semiconductors and ternary and quaternary chalcogenide compounds.

  7. Self-powered radiation detectors

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Todt, W.H.

    1982-01-01

    A self-powered nuclear radiation detector has an emitter electrode of an alloy of a first major constituent metal having a desired high radiation response, and a second minor constituent which imparts to the alloy a desired thermal or mechanical characteristic without diminishing the desired high radiation response. A gamma responsive self-powered detector is detailed which has an emitter with lead as the major constituent, with the minor constituent selected from aluminum, copper, nickel, platinum, or zinc. (author)

  8. Defect kinetics in novel detector materials

    CERN Document Server

    MacEvoy, B C

    2000-01-01

    Silicon particle detectors will be used extensively in experiments at the CERN Large Hadron Collider, where unprecedented particle fluences will cause significant atomic displacement damage. We present a model of the evolution of defect concentrations and consequent electrical behaviour in "novel" detector materials with various oxygen and carbon impurity concentrations. The divacancy-oxygen (V/sub 2/O) defect is identified as the cause of changes in device characteristics during /sup 60/Co gamma irradiation. In the case of hadron irradiation changes in detector doping concentration (N/sub eff/) are dominated by cluster defects, in particular the divacancy (V/sub 2/), which exchange charge directly via a non-Shockley-Read- Hall mechanism. The V/sub 2/O defect also contributes to Ne/sub eff/. This defect is more copiously produced during 24 GeV/c proton irradiation than during 1 MeV neutron irradiation on account of the higher vacancy introduction rate, hence the radiation hardness of materials is more sensiti...

  9. Radiation detectors as surveillance monitors for IAEA safeguards

    International Nuclear Information System (INIS)

    Fehlau, P.E.; Dowdy, E.J.

    1980-10-01

    Radiation detectors used for personnel dosimetry are examined for use under IAEA Safeguards as monitors to confirm the passage or nonpassage (YES/NO) of plutonium-bearing nuclear material at barrier penetrations declared closed. In this application where backgrounds are ill defined, no advantage is found for a particular detector type because of intrinsic efficiency. Secondary considerations such as complexity, ease of tamper-proofing, and ease of readout are used to recommend specific detector types for routine monitoring and for data-base measurements. Recommendations are made for applications, data acquisition, and instrument development

  10. Radiation detectors as surveillance monitors for IAEA safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Fehlau, P.E.; Dowdy, E.J.

    1980-10-01

    Radiation detectors used for personnel dosimetry are examined for use under IAEA Safeguards as monitors to confirm the passage or nonpassage (YES/NO) of plutonium-bearing nuclear material at barrier penetrations declared closed. In this application where backgrounds are ill defined, no advantage is found for a particular detector type because of intrinsic efficiency. Secondary considerations such as complexity, ease of tamper-proofing, and ease of readout are used to recommend specific detector types for routine monitoring and for data-base measurements. Recommendations are made for applications, data acquisition, and instrument development.

  11. Ionizing radiation detector

    Science.gov (United States)

    Thacker, Louis H.

    1990-01-01

    An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

  12. Electret radiation detector

    International Nuclear Information System (INIS)

    Kubu, M.

    1981-01-01

    The electret radiation detector consists of 30 to 35% of bee wax and of 65 to 70% of colophony. It is mainly the induction conductivity of charo.es between the dipoles in the electret which is used for detection. In the manufacture of the detector, the average atomic number of the electret can be altered by adding various compounds, such as ZnO, which also increases efficiency for gamma radiation. An alpha or beta emitter can also be built-in in the electret. (B.S.)

  13. Radiation damage measurements on CZT drift strip detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Korsbech, Uffe C C

    2003-01-01

    from 2 x 10(8) to 60 x 10(8) p(+)/cm(2). Even for the highest fluences, which had a dramatic effect on the spectroscopic performance, we were able to recover the detectors after an appropriate annealing procedure. The radiation damage was studied as a function of depth inside the detector material...... with the proton dose. The radiation contribution to the electron trapping was found to obey the following relation: (mutau(e)(-1))(rad) = (2.5+/-0.2) x 10(-7) x Phi (V/cm)(2) with the proton fluence, Phi in p(+)/cm(2). The trapping depth dependence, however, did not agree well with the damage profile calculated...

  14. Semiconductor ionizino. radiation detectors

    International Nuclear Information System (INIS)

    1982-01-01

    Spectrometric semiconductor detectors of ionizing radiation with the electron-hole junction, based on silicon and germanium are presented. The following parameters are given for the individual types of germanium detectors: energy range of detected radiation, energy resolution given as full width at half maximum (FWHM) and full width at one tenth of maximum (FWTM) for 57 Co and 60 Co, detection sensitivity, optimal voltage, and electric capacitance at optimal voltage. For silicon detectors the value of FWHM for 239 Pu is given, the sensitive area and the depth of the sensitive area. (E.S.)

  15. International workshop on advanced materials for high precision detectors. Proceedings

    International Nuclear Information System (INIS)

    Nicquevert, B.; Hauviller, C.

    1994-01-01

    These proceedings gather together the contributions to the Workshop on Advanced Materials for High Precision Detectors, which was held from 28-30 September 1994 in Archamps, Haute-Savoie, France. This meeting brought together international experts (researchers, physicists and engineers) in the field of advanced materials and their use in high energy physics detectors or spacecraft applications. Its purpose was to discuss the status of the different materials currently in use in the structures of detectors and spacecraft, together with their actual performances, technological implications and future prospects. Environmental effects, such as those of moisture and radiation, were discussed, as were design and manufacturing technologies. Some case studies were presented. (orig.)

  16. Large arrays of discrete ionizing radiation detectors multiplexed using fluorescent optical converters

    International Nuclear Information System (INIS)

    Koslow, E.E.; Edelman, R.R.

    1985-01-01

    This invention provides a radiation imaging system employing arrays of scintillators. An object of the invention is to produce a detector with high spatial resolution, high gamma-photon absorption efficiency, excellent source and detector scatter rejection, and utilizing low-cost solid state opto-electronic devices. In one embodiment, it provides a radiation detection and conversion apparatus having an array of optically isolated radiation sensitive elements that emit optical radiation upon absorption of ionizing radiation. An array of channels, comprising a material that absorbs and traps the radiation emitted and transports it or radiation that has been shifted to longer wavelengths, is placed near the radiation-sensitive elements. Electro-optical detectors that convert the transported radiation into electrical signals are coupled to the channels. The activation of one of the electro-optical devices by radiation from one of the channels indicates that at least one of the radiation-sensitive elements near that channel has absorbed a quantity of radiation

  17. Radiation damage: special reference to gas filled radiation detectors

    International Nuclear Information System (INIS)

    Gaur, Sudha; Joshi, Pankaj Kumar; Rathore, Shakuntla

    2012-01-01

    Radiation damage is a term associated with ionizing radiation. In gas filled particle detectors, radiation damage to gases plays an important role in the device's ageing, especially in devices exposed to high intensity radiation, e.g. detector for the large hadrons collide. Ionization processes require energy above 10 eV, while splitting covalent bond in molecules and generating free radical require only 3-4 eV. The electrical discharges initiated by the ionization event by the particles result in plasma populated by large amount of free radical. The highly reactive free radical can recombine back to original molecules, or initiate a chain of free radical polymerization reaction with other molecules, yielding compounds with increasing molecular weight. These high molecular weight compounds then precipitate from gases phase, forming conductive or non-conductive deposits on the electrodes an insulating surfaces of the detector and distorting it's response. Gases containing hydrocarbon quenchers, e.g. argon-methane, are typically sensitive to ageing by polymerization; addition of oxygen tends to lower the ageing rates. Trace amount of silicon oils, present form out gassing of silicon elastomers and especially from traces of silicon lubricant tend to decompose and form deposits of silicon crystals on the surfaces. Gases mixture of argon (or xenon) with CO 2 and optimally also with 2-3 % of oxygen are highly tolerant to high radiation fluxes. The oxygen is added as noble gas with CO 2 has too high transparency for high energy photons; ozone formed from the oxygen is a strong absorber of ultra violet photons. Carbon tetra fluoride can be used as a component of the gas for high-rate detectors; the fluorine radical produced during the operation however limit the choice of materials for the chambers and electrodes (e.g. gold electrodes are required, as the fluorine radicals attack metals, forming fluorides). Addition of carbon tetra fluoride can however eliminate the

  18. Improved spectrometric characteristics of thallium bromide nuclear radiation detectors

    CERN Document Server

    Hitomi, K; Shoji, T; Suehiro, T; Hiratate, Y

    1999-01-01

    Thallium bromide (TlBr) is a compound semiconductor with a high atomic number and wide band gap. In this study, nuclear radiation detectors have been fabricated from the TlBr crystals. The TlBr crystals were grown by the horizontal travelling molten zone (TMZ) method using the materials purified by many pass zone refining. The crystals were characterized by measuring the resistivity, the mobility-lifetime (mu tau) product and the energy required to create an electron-hole pair (the epsilon value). Improved energy resolution has been obtained by the TlBr radiation detectors. At room temperature the full-width at half-maximum (FWHM) for the 59.5, 122 and 662 keV gamma-ray photo peak obtained from the detectors were 3.3, 8.8 and 29.5 keV, respectively. By comparing the saturated peak position of the TlBr detector with that of the CdTe detector, the epsilon value has been estimated to be about 5.85 eV for the TlBr crystal.

  19. Radiation hardness of silicon detectors manufactured on wafers from various sources

    International Nuclear Information System (INIS)

    Dezillie, B.; Bates, S.; Glaser, M.; Lemeilleur, F.; Leroy, C.

    1997-01-01

    Impurity concentrations in the initial silicon material are expected to play an important role for the radiation hardness of silicon detectors, during their irradiation and for their evolution with time after irradiation. This work reports on the experimental results obtained with detectors manufactured using various float-zone (FZ) and epitaxial-grown material. Preliminary results comparing the changes in leakage current and full depletion voltage of FZ and epitaxial detectors as a function of fluence and of time after 10 14 cm -2 proton irradiation are given. The measurement of charge collection efficiency for epitaxial detectors is also presented. (orig.)

  20. Methods for radiation detection and characterization using a multiple detector probe

    Science.gov (United States)

    Akers, Douglas William; Roybal, Lyle Gene

    2014-11-04

    Apparatuses, methods, and systems relating to radiological characterization of environments are disclosed. Multi-detector probes with a plurality of detectors in a common housing may be used to substantially concurrently detect a plurality of different radiation activities and types. Multiple multi-detector probes may be used in a down-hole environment to substantially concurrently detect radioactive activity and contents of a buried waste container. Software may process, analyze, and integrate the data from the different multi-detector probes and the different detector types therein to provide source location and integrated analysis as to the source types and activity in the measured environment. Further, the integrated data may be used to compensate for differential density effects and the effects of radiation shielding materials within the volume being measured.

  1. Radiation energy detector and analyzer

    International Nuclear Information System (INIS)

    Roberts, T.G.

    1981-01-01

    A radiation detector array and a method for measuring the spectral content of radiation. The radiation sensor or detector is an array or stack of thin solid-electrolyte batteries. The batteries, arranged in a stack, may be composed of independent battery cells or may be arranged so that adjacent cells share a common terminal surface. This common surface is possible since the polarity of the batteries with respect to an adjacent battery is unrestricted, allowing a reduction in component parts of the assembly and reducing the overall stack length. Additionally, a test jig or chamber for allowing rapid measurement of the voltage across each battery is disclosed. A multichannel recorder and display may be used to indicate the voltage gradient change across the cells, or a small computer may be used for rapidly converting these voltage readings to a graph of radiation intensity versus wavelength or energy. The behavior of the batteries when used as a radiation detector and analyzer are such that the voltage measurements can be made at leisure after the detector array has been exposed to the radiation, and it is not necessary to make rapid measurements as is now done

  2. Development of superconducting tunnel junction radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Katagiri, Masaki; Kishimoto, Maki; Ukibe, Masahiro; Nakamura, Tatsuya; Nakazawa, Masaharu [Japan Atomic Energy Research Inst., Tokyo (Japan); Kurakado, Masahiko; Ishibashi, Kenji; Maehata, Keisuke

    1998-07-01

    Study on development of high energy resolution X-ray detector using superconducting tunnel junction (STJ) for radiation detection was conducted for 5 years under cooperation of University of Tokyo group and Kyushu University group by Quantum measurement research group of Advanced fundamental research center of JAERI. As the energy resolution of STJ could be obtained better results than that of Si semiconductor detector told to be actually best at present, this study aimed to actualize an X-ray detector usable for the experimental field and to elucidate radiation detection mechanism due to STJ. The STJ element used for this study was the one developed by Kurakado group of Nippon Steel Corp. As a results, some technical problems were almost resolved, which made some trouble when using the STJ element to detection element of X-ray spectrometer. In order to make the X-ray detector better, it is essential to manufacture a STJ element and develop serial junction type STJ element on the base of optimization of the element structure and selection and single crystallization of new superconducting materials such as Ta and others, activating the research results. (G.K.)

  3. Ionizing radiation detector using multimode optical fibers

    International Nuclear Information System (INIS)

    Suter, J.J.; Poret, J.C.; Rosen, M.; Rifkind, J.M.

    1993-01-01

    An optical ionizing radiation detector, based on the attenuation of 850-nm light in 50/125-μm multimode fibers, is described. The detector is especially well suited for application on spacecraft because of its small design. The detection element consists of a section of coiled fibers that has been designed to strip higher-order optical modes. Cylindrical radiation shields with atomic numbers ranging from Z = 13 (aluminum too) Z = 82 (lead) were placed around the ionizing radiation detector so that the effectiveness of the detector could be measured. By exposing the shields and the detector to 1.25-MeV cobalt 60 radiation, the mass attenuation coefficients of the shields were measured. The detector is based on the phenomenon that radiation creates optical color centers in glass fibers. Electron spin resonance spectroscopy performed on the 50/125-μm fibers showed the presence of germanium oxide and phosphorus-based color centers. The intensity of these centers is directly related to the accumulated gamma radiation

  4. Diamond detectors for synchrotron radiation X-ray applications

    Energy Technology Data Exchange (ETDEWEB)

    De Sio, A. [Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Roma (Italy); Department of Astronomy and Space Science, Universita di Firenze, L.go E. Fermi 2, 50125 Firenze (Italy)], E-mail: desio@arcetri.astro.it; Pace, E. [Department of Astronomy and Space Science, Universita di Firenze, L.go E. Fermi 2, 50125 Firenze (Italy); INFN, Sezione di Firenze, v. G. Sansone 1, Sesto Fiorentino, Firenze (Italy); Cinque, G.; Marcelli, A. [Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Roma (Italy); Achard, J.; Tallaire, A. [LIMHP-CNRS, University of Paris XIII, 99 Avenue JB Clement, 93430 Villetaneuse (France)

    2007-07-15

    Due to its unique physical properties, diamond is a very appealing material for the development of electronic devices and sensors. Its wide band gap (5.5 eV) endows diamond based devices with low thermal noise, low dark current levels and, in the case of radiation detectors, high visible-to-X-ray signal discrimination (visible blindness) as well as high sensitivity to energies greater than the band gap. Furthermore, due to its radiation hardness diamond is very interesting for applications in extreme environments, or as monitor of high fluency radiation beams. In this work the use of diamond based detectors for X-ray sensing is discussed. On purpose, some photo-conductors based on different diamond types have been tested at the DAFNE-L synchrotron radiation laboratory at Frascati. X-ray sensitivity spectra, linearity and stability of the response of these diamond devices have been measured in order to evidence the promising performance of such devices.

  5. Diamond detectors for synchrotron radiation X-ray applications

    International Nuclear Information System (INIS)

    De Sio, A.; Pace, E.; Cinque, G.; Marcelli, A.; Achard, J.; Tallaire, A.

    2007-01-01

    Due to its unique physical properties, diamond is a very appealing material for the development of electronic devices and sensors. Its wide band gap (5.5 eV) endows diamond based devices with low thermal noise, low dark current levels and, in the case of radiation detectors, high visible-to-X-ray signal discrimination (visible blindness) as well as high sensitivity to energies greater than the band gap. Furthermore, due to its radiation hardness diamond is very interesting for applications in extreme environments, or as monitor of high fluency radiation beams. In this work the use of diamond based detectors for X-ray sensing is discussed. On purpose, some photo-conductors based on different diamond types have been tested at the DAFNE-L synchrotron radiation laboratory at Frascati. X-ray sensitivity spectra, linearity and stability of the response of these diamond devices have been measured in order to evidence the promising performance of such devices

  6. Amorphous silicon radiation detectors

    Science.gov (United States)

    Street, Robert A.; Perez-Mendez, Victor; Kaplan, Selig N.

    1992-01-01

    Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification.

  7. Porous material neutron detector

    Science.gov (United States)

    Diawara, Yacouba [Oak Ridge, TN; Kocsis, Menyhert [Venon, FR

    2012-04-10

    A neutron detector employs a porous material layer including pores between nanoparticles. The composition of the nanoparticles is selected to cause emission of electrons upon detection of a neutron. The nanoparticles have a maximum dimension that is in the range from 0.1 micron to 1 millimeter, and can be sintered with pores thereamongst. A passing radiation generates electrons at one or more nanoparticles, some of which are scattered into a pore and directed toward a direction opposite to the applied electrical field. These electrons travel through the pore and collide with additional nanoparticles, which generate more electrons. The electrons are amplified in a cascade reaction that occurs along the pores behind the initial detection point. An electron amplification device may be placed behind the porous material layer to further amplify the electrons exiting the porous material layer.

  8. Signal processing for radiation detectors

    CERN Document Server

    Nakhostin, Mohammad

    2018-01-01

    This book provides a clear understanding of the principles of signal processing of radiation detectors. It puts great emphasis on the characteristics of pulses from various types of detectors and offers a full overview on the basic concepts required to understand detector signal processing systems and pulse processing techniques. Signal Processing for Radiation Detectors covers all of the important aspects of signal processing, including energy spectroscopy, timing measurements, position-sensing, pulse-shape discrimination, and radiation intensity measurement. The book encompasses a wide range of applications so that readers from different disciplines can benefit from all of the information. In addition, this resource: * Describes both analog and digital techniques of signal processing * Presents a complete compilation of digital pulse processing algorithms * Extrapolates content from more than 700 references covering classic papers as well as those of today * Demonstrates concepts with more than 340 origin...

  9. LL13-MatModelRadDetect-PD2Jf Final Report: Materials Modeling for High-Performance Radiation Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lordi, Vincenzo [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-12-11

    The aims of this project are to enable rational materials design for select high-payoff challenges in radiation detection materials by using state-of-the-art predictive atomistic modeling techniques. Three specific high-impact challenges are addressed: (i) design and optimization of electrical contact stacks for TlBr detectors to stabilize temporal response at room-temperature; (ii) identification of chemical design principles of host glass materials for large-volume, low-cost, highperformance glass scintillators; and (iii) determination of the electrical impacts of dislocation networks in Cd1-xZnxTe (CZT) that limit its performance and usable single-crystal volume. The specific goals are to establish design and process strategies to achieve improved materials for high performance detectors. Each of the major tasks is discussed below in three sections, which include the goals for the task and a summary of the major results, followed by a listing of publications that contain the full details, including details of the methodologies used. The appendix lists 12 conference presentations given for this project, including 1 invited talk and 1 invited poster.

  10. The Use of Radiation Detectors in Medicine: Radiation Detectors for Morphological Imaging (1/3)

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    The development of radiation detectors in the field of nuclear and particle physics has had a terrific impact in medical imaging since this latter discipline took off in late ’70 with the invention of the CT scanners. The massive use in High Energy Physics of position sensitive gas detectors, of high Z and high density scintillators coupled to Photomultiplier (PMT) and Position Sensitive Photomultipliers (PSPMT), and of solid state detectors has triggered during the last 30 years a series of novel applications in Medical Imaging with ionizing radiation. The accelerated scientific progression in genetics and molecular biology has finally generated what it is now called Molecular Imaging. This field of research presents additional challenges not only in the technology of radiation detector, but more and more in the ASIC electronics, fast digital readout and parallel software. In this series of three lectures I will try to present how high energy physics and medical imaging development have both benefited by t...

  11. The Use of Radiation Detectors in Medicine: Radiation Detectors for Functional Imaging (2/3)

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    The development of radiation detectors in the field of nuclear and particle physics has had a terrific impact in medical imaging since this latter discipline took off in late ’70 with the invention of the CT scanners. The massive use in High Energy Physics of position sensitive gas detectors, of high Z and high density scintillators coupled to Photomultiplier (PMT) and Position Sensitive Photomultipliers (PSPMT), and of solid state detectors has triggered during the last 30 years a series of novel applications in Medical Imaging with ionizing radiation. The accelerated scientific progression in genetics and molecular biology has finally generated what it is now called Molecular Imaging. This field of research presents additional challenges not only in the technology of radiation detector, but more and more in the ASIC electronics, fast digital readout and parallel software. In this series of three lectures I will try to present how high energy physics and medical imaging development have both benefited by t...

  12. Modeling of diamond radiation detectors

    International Nuclear Information System (INIS)

    Milazzo, L.; Mainwood, A.

    2004-01-01

    We have built up a computer simulation of the detection mechanism in the diamond radiation detectors. The diamond detectors can be fabricated from a chemical vapour deposition polycrystalline diamond film. In this case, the trapping-detrapping and recombination at the defects inside the grains and at the grain boundaries degrade the transport properties of the material and the charge induction processes. These effects may strongly influence the device's response. Previous simulations of this kind of phenomena in the diamond detectors have generally been restricted to the simple detector geometries and homogeneous distribution of the defects. In our model, the diamond film (diamond detector) is simulated by a grid. We apply a spatial and time discretization, regulated by the grid resolution, to the equations describing the charge transport and, by using the Shockley-Ramo theorem, we calculate the signal induced on the electrodes. In this way, we can simulate the effects of the nonhomogeneous distributions of the trapping, recombination, or scattering centers and can investigate the differences observed when different particles, energies, and electrode configurations are used. The simulation shows that the efficiency of the detector increases linearly with the average grain size, that the charge collection distance is small compared to the dimensions of a single grain, and that for small grains, the trapping at the intragrain defects is insignificant compared to the effect of the grain boundaries

  13. Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe

    Science.gov (United States)

    Majewski, Stanislaw; Kross, Brian J.; Zorn, Carl J.; Majewski, Lukasz A.

    1996-01-01

    An optimized examination system and method based on the Reverse Geometry X-Ray.RTM. (RGX.RTM.) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging.

  14. Manufacturing of different gel detectors and their calibration for spatial radiation dose measurements

    International Nuclear Information System (INIS)

    Bero, M.

    2008-05-01

    Three types of gel dosemeter have been made and their most important properties for radiation dosimetry were studied. The comparison between the three categories helps to widen knowledge in each of these detectors and to establish a method for the preparation as well as testing of this radiation sensitive materials. Experiments show the technical application possibility for using these gel detectors to measure the spatial radiation dose distribution in the range of doses given for cancer treatment. The experimental results give some important characteristic for the three gel dosemeter used in comparison to that of the traditional dosimetry systems. It also shows the simplicity of manufacturing the dosemeter from low cost materials and its radiation response to ionizing. The relationships between the dosemeter response and the dose rate as well as the radiation energy were also investigated. Important subjects that have been also taken into consideration are the effects of ambient conditions and storage likelihood of the studied materials. Recommendation was made for the use of these materials in practical applications and for handling as well as their long term storage possibility. (author)

  15. Conceptual Design of Simulated Radiation Detector for Nuclear Forensics Exercise Purposes

    International Nuclear Information System (INIS)

    Kim, Jae Kwang; Baek, Ye Ji; Lee, Seung Min

    2016-01-01

    A site associated with an illicit trafficking or security event may contain trace evidence of criminal or malicious acts involving radioactive material. Such a site is called a radiological crime scene. Management of a radiological crime scene requires a process of ensuring an orderly accurate and effective collection and preservation of evidence. In order to effectively address such a security event, first responders and/or on-scene investigators need to exercise detecting, locating and recovering materials at the scene of the incident. During such the exercise, a sealed source can be used. This source is allowed to be a very small amount for exercises as there is the limit on the amount of radioactive material that causes no harm. So it is typically difficult to be found by some radiation detectors that the exercises have little effect on improving the ability of trainees. Therefore, we developed a conceptual design of a simulation radiation detector coupled with simulation sources which are designed to imitate a significant amount radioactive material for the purpose of a nuclear forensics exercise. With the potential of a terrorist attack using radioactive materials, the first responders should regularly perform the nuclear forensics exercise in order to prepare for a recovery operation. In this regard, some devices such as simulated detector, coupled with a virtual source, can replace a real detector and a surrogate source of material in field exercises. BLE technology could be applied to create similar environments to that of an actual radiological attack. The detector coupled with the simulated sources could be very helpful for first responders in testing and improving their ability in the case of a nuclear security event. In addition, this conceptual design could be extended to develop a simulated dosimeter coupled with a beacon signal emitters. The dosimeter is a personal device used for indicating the cumulated exposure of radiation in real time in the

  16. Conceptual Design of Simulated Radiation Detector for Nuclear Forensics Exercise Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Kwang; Baek, Ye Ji; Lee, Seung Min [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2016-05-15

    A site associated with an illicit trafficking or security event may contain trace evidence of criminal or malicious acts involving radioactive material. Such a site is called a radiological crime scene. Management of a radiological crime scene requires a process of ensuring an orderly accurate and effective collection and preservation of evidence. In order to effectively address such a security event, first responders and/or on-scene investigators need to exercise detecting, locating and recovering materials at the scene of the incident. During such the exercise, a sealed source can be used. This source is allowed to be a very small amount for exercises as there is the limit on the amount of radioactive material that causes no harm. So it is typically difficult to be found by some radiation detectors that the exercises have little effect on improving the ability of trainees. Therefore, we developed a conceptual design of a simulation radiation detector coupled with simulation sources which are designed to imitate a significant amount radioactive material for the purpose of a nuclear forensics exercise. With the potential of a terrorist attack using radioactive materials, the first responders should regularly perform the nuclear forensics exercise in order to prepare for a recovery operation. In this regard, some devices such as simulated detector, coupled with a virtual source, can replace a real detector and a surrogate source of material in field exercises. BLE technology could be applied to create similar environments to that of an actual radiological attack. The detector coupled with the simulated sources could be very helpful for first responders in testing and improving their ability in the case of a nuclear security event. In addition, this conceptual design could be extended to develop a simulated dosimeter coupled with a beacon signal emitters. The dosimeter is a personal device used for indicating the cumulated exposure of radiation in real time in the

  17. Semiconductor radiation detectors. Device physics

    International Nuclear Information System (INIS)

    Lutz, G.

    2007-01-01

    Starting from basic principles, the author, whose own contributions to these developments have been significant, describes the rapidly growing field of modern semiconductor detectors used for energy and position measurement radiation. This development was stimulated by requirements in elementary particle physics where it has led to important scientific discoveries. It has now spread to many other fields of science and technology. The book is written in a didactic way and includes an introduction to semiconductor physics. The working principles of semiconductor radiation detectors are explained in an intuitive way, followed by formal quantitative analysis. Broad coverage is also given to electronic signal readout and to the subject of radiation damage. The book is the first to comprehensively cover the semiconductor radiation detectors currently in use. It is useful as a teaching guide and as a reference work for research and applications. (orig.)

  18. Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

    International Nuclear Information System (INIS)

    Bero, M A; Abukassem, I

    2009-01-01

    Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

  19. Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

    Science.gov (United States)

    Bero, M. A.; Abukassem, I.

    2009-05-01

    Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

  20. Detector for atomic particles and ionizing radiations

    International Nuclear Information System (INIS)

    Mallet, Georges; Ythier, Christian.

    1976-01-01

    The aim of this invention is to provide improved detectors of atomic particles and of ionising radiations, having maximum sensitivity, by virtually suppressing all absorption of the radiation scattered by the main detector, so that these detectors are particularly suitable for fitting to anti-Compton spectrometers. Reference is particularly made to detectors of the Ge(Li) type, lithium compensated germanium, which are the most used. It is however made clear that this choice is not restrictive and that this invention not only applies to all known types of detectors and particularly to scintillator detectors, for instance to detectors such as NaI (Tl), composed of a monocrystal of a thallium activated alkaline halogenide, but also to gas, ionisation chamber and luminescent chamber type detectors and in general to all the known devices that convert the energy of particles into electric signals. Owing to the fact that the walls of the enclosure containing the main detector are composed, in the part around this detector, of an auxiliary detector, the latter detects virtually all the radiations scattered by the main detector. It does so without any loss due to the absorption of these radiations (a) by the metal walls of the enclosure usually containing the main detector and (b) by the walls of the auxiliary detector casing. It results from this that the detectors of the invention enable coincidence or anti-coincidence spectrometers with a very high performance to be made [fr

  1. Application of solid state nuclear track detectors in radiation protection

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subba Ramu, M.C.; Mishra, U.C.

    1989-01-01

    This article reviews the current status of the application of nuclear track detectors with emphasis on recent developments in the field of radiation protection. Track etch detectors have been used for the measurements of low level radiation in the environment, fast neutron and radon daughter inhalation dose. Recent developments in the field of dosimetry seem to be promising. In fast neutron dosimetry, track etch detectors can be used without inclusion of fissile materials by using the electrochemical etching technique. These detectors can provide important information in the energy range upto 250 keV. Survey of this range of energy with TLD is difficult because they are extremely energy dependent and over-respond to low energy neutrons. Measurement of radon using track detectors can help to lower the cost of the radon dosimeters. Certain detectors are sensitive to alpha particles from radon and their progeny. Higher sensitivity permits their use in a passive type of personnel dosimeter, which does not require the troublesome aspects of air sampling for the collection of radon daughter samples. (author), 38 refs., 8 tabs., 12 figs

  2. Silicon radiation detector

    International Nuclear Information System (INIS)

    Benc, I.; Kerhart, J.; Kopecky, J.; Krca, P.; Veverka, V.; Weidner, M.; Weinova, H.

    1992-01-01

    The silicon radiation detector, which is designed for the detection of electrons with energies above 500 eV and of radiation within the region of 200 to 1100 nm, comprises a PIN or PNN + type photodiode. The active acceptor photodiode is formed by a detector surface of shallow acceptor diffusion surrounded by a collector band of deep acceptor diffusion. The detector surface of shallow P-type diffusion with an acceptor concentration of 10 15 to 10 17 atoms/cm 3 reaches a depth of 40 to 100 nm. One sixth to one eighth of the collector band width is overlapped by the P + collector band at a width of 150 to 300 μm with an acceptor concentration of 10 20 to 10 21 atoms/cm 3 down a depth of 0.5 to 3 μm. This band is covered with a conductive layer, of NiCr for instance. (Z.S.)

  3. New materials for radiation dosimetry

    International Nuclear Information System (INIS)

    Madatov, R.S.; Necefov, A.I.; Qabulov, I.A.; Seferova, S.

    2002-01-01

    Full text: The utilization of nuclear energy and beginning the production of radioactive nuclides are the reasons for radiation safety problems actualization. As a result of this, a new specific peculiar properties such as environmental, psychological, biological and etc. that are originated due to radioactive irradiation have been observed. Dosimetric equipment is used with the purpose of environmental protection, radiation detection, radiation safety assessment and distribution of information. The principle of operation of this equipment is based on the ionization effect. However, the equipment is differed one from another by the registration method. The main imperfections of dosimetric equipment are a narrowness of irradiation range as well as small values of energy sensitivity and stability. Taking into account of all above-stated imperfections, the obtaining of a new radiation-resistant materials and production of modern dosimetric detectors on their basis are one of the actual problems in dosimetry. At present the detectors on the basis of semiconductor materials such as Ge, Si, CdTe, CdS and etc. are widespread. Their principle of operation is also based on the ionization process, but the mechanism of its is differ from gas detectors. It is connected with that the carrier mobility for electrons in semiconductors is varied from 1400 up to 4000 cm 2 /(V·sec), and for holes from 400 up to 2000 cm 2 /(V·sec). It provides high level of detection for detectors on the basis of semiconductors. Initial conductivity of semiconductors differs one from another and it restricts the efficiency of detectors. The investigations on two directions have been carried out by this reason. The first direction is the increasing of radiation resistance of existing materials. The second direction is the obtaining of a new materials with high radiation resistance. It is known that the laminated materials on the basis of tellurium, for instance TeInS 2 are high sensitivity to X-radiation

  4. Silicon detectors operating beyond the LHC collider conditions: scenarios for radiation fields and detector degradation

    International Nuclear Information System (INIS)

    Lazanu, I.; Lazanu, S.

    2004-01-01

    Particle physics makes its greatest advances with experiments at the highest energies. The way to advance to a higher energy regime is through hadron colliders, or through non-accelerator experiments, as for example the space astroparticle missions. In the near future, the Large Hadron Collider (LHC) will be operational, and beyond that, its upgrades: the Super-LHC (SLHC) and the hypothetical Very Large Hadron Collider (VLHC). At the present time, there are no detailed studies for future accelerators, except those referring to LHC. For the new hadron collider LHC and some of its updates in luminosity and energy, the silicon detectors could represent an important option, especially for the tracking system and calorimetry. The main goal of this paper is to analyse the expected long-time degradation of the silicon as material and for silicon detectors, during continuous radiation, in these hostile conditions. The behaviour of silicon in relation to various scenarios for upgrade in energy and luminosity is discussed in the frame of a phenomenological model developed previously by the authors and now extended to include new mechanisms, able to explain and give solutions to discrepancies between model predictions and detector behaviour after hadron irradiation. Different silicon material parameters resulting from different technologies are considered to evaluate what materials are harder to radiation and consequently could minimise the degradation of device parameters in conditions of continuous long time operation. (authors)

  5. BNLs Synchrotron-radiation Research Hub for Characterizing Detection Materials and Devices for the NA-22 Community

    Energy Technology Data Exchange (ETDEWEB)

    Camarda, G. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Bolotnikov, A. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Cui, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hossain, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roy, U. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Vanier, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); McDowell, Alastair [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rosen, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Labrum, Joseph [Univ. of California, Berkeley, CA (United States)

    2017-03-01

    The goal of this project is to obtain and characterize scintillators, emerging- and commercial-compoundsemiconductor radiation- detection materials and devices provided by vendors and research organizations. The focus of our proposed research is to clarify the role of the deleterious defects and impurities responsible for the detectors' non-uniformity in scintillating crystals, commercial semiconductor radiation-detector materials, and in emerging R&D ones. Some benefits of this project addresses the need for fabricating high-performance scintillators and compound-semiconductor radiation-detectors with the proven potential for large-scale manufacturing. The findings help researchers to resolve the problems of non-uniformities in scintillating crystals, commercial semiconductor radiation-detector materials, and in emerging R&D ones.

  6. Wide Band-Gap Semiconductor Radiation Detectors: Science Fiction, Horror Story, or Headlines (460th Brookhaven Lecture)

    International Nuclear Information System (INIS)

    James, Ralph

    2010-01-01

    With radiation constantly occurring from natural sources all around us -- from food, building materials, and rays from the sun, to name a few -- detecting radiotracers for medical procedures and other radiation to keep people safe is not easy. In order to make better use of radiation to diagnose or treat certain health conditions, or to track radiological materials being transported, stored, and used, the quest is on to develop improved radiation detectors. James gives a brief introduction on radiation detection and explain how it is used in applications ranging from medical to homeland security. He then discusses how new materials and better ways to analyze them here at the National Synchrotron Light Source (NSLS) and the future NSLS-II will lead to a new class of radiation detectors that will provide unprecedented advances in medical and industrial imaging, basic science, and the nonproliferation of nuclear materials.

  7. Seismic restraint means for radiation detector

    International Nuclear Information System (INIS)

    Underwood, R.H.; Todt, W.H.

    1983-01-01

    Seismic restraint means are provided for mounting an elongated, generally cylindrical nuclear radiation detector within a tubular thimble in a nuclear reactor monitor system. The restraint means permits longitudinal movement of the radiation detector into and out of the thimble. Each restraint means comprises a split clamp ring and a plurality of symmetrically spaced support arms pivotally mounted on the clamp ring. Each support arm has spring bias means and thimble contact means eg insulating rollers whereby the contact means engage the thimble with a constant predetermined force which minimizes seismic vibration action on the radiation detector. (author)

  8. Manufacturing process for electrodes for ionizing radiation detectors

    International Nuclear Information System (INIS)

    Tirelli, M.G.; Hecquet, R.

    1987-01-01

    A manufacturing proces for electrodes for ionizing radiation detectors, particularly electrodes for X-ray multidetectors, is proposed. It consists of electrodepositing at least one layer of an electrically conducting material on at least one side of a relatively flat plate. A ductile material is used to form the conducting layer. The assembly formed by the plate covered by the ductile conducting material is subjected to pressing to crush the ductile conducting material at least in the zones where the assembly formed by the plate and the covering material has a total thickness superior to a constant thickness desired for the electrode [fr

  9. The transition radiation detector of the CBM experiment at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, Cyrano [Institut fuer Kernphysik, WWU Muenster (Germany)

    2016-07-01

    The Compressed Baryonic Matter (CBM) experiment is a fixed target heavy-ion experiment at the future FAIR accelerator facility. The CBM Transition Radiation Detector (TRD) is one of the key detectors to provide electron identification above momenta of 1 GeV/c and charged particle tracking. Due its capability to identify charged particles via their specific energy loss, the TRD in addition will provide valuable information for the measurement of fragments. These requirements can be fulfilled with a XeCO{sub 2} based Multi-Wire Proportional Counter (MWPC) detector in combination with an adequate radiator. The default MWPC is composed of a symmetric amplification area of 7 mm thickness, followed by a 5 mm drift region to enhance the TR-photon absorption probability in the active gas volume. This geometry provides also efficient and fast signal creation, as well as read-out, of the order of 200 μs per charged particle track. The performance of this detector is maximized by reducing the material budget between the radiator and gas volume to a minimum. The full detector at SIS100 will be composed of 200 modules in 2 sizes. To limit cost and production time the number of various module types is limited to 6 types and 4 types of Front End Board (FEB) flavors are required. An overview of the design and performance of the TRD detector is given.

  10. Solid state detector design

    International Nuclear Information System (INIS)

    Gunarwan Prayitno; Ahmad Rifai

    2010-01-01

    Much has been charged particle detector radiation detector made by the industry, especially those engaged in the development of detection equipment and components. The development and further research will be made solid state detector with silicon material. To be able to detect charged particles (radiation), required the processing of silicon material into the detector material. The method used to make silicon detector material is a lithium evaporations. Having formed an intrinsic region contactor installation process, and with testing. (author)

  11. Radiation imaging with optically read out GEM-based detectors

    Science.gov (United States)

    Brunbauer, F. M.; Lupberger, M.; Oliveri, E.; Resnati, F.; Ropelewski, L.; Streli, C.; Thuiner, P.; van Stenis, M.

    2018-02-01

    Modern imaging sensors allow for high granularity optical readout of radiation detectors such as MicroPattern Gaseous Detectors (MPGDs). Taking advantage of the high signal amplification factors achievable by MPGD technologies such as Gaseous Electron Multipliers (GEMs), highly sensitive detectors can be realised and employing gas mixtures with strong scintillation yield in the visible wavelength regime, optical readout of such detectors can provide high-resolution event representations. Applications from X-ray imaging to fluoroscopy and tomography profit from the good spatial resolution of optical readout and the possibility to obtain images without the need for extensive reconstruction. Sensitivity to low-energy X-rays and energy resolution permit energy resolved imaging and material distinction in X-ray fluorescence measurements. Additionally, the low material budget of gaseous detectors and the possibility to couple scintillation light to imaging sensors via fibres or mirrors makes optically read out GEMs an ideal candidate for beam monitoring detectors in high energy physics as well as radiotherapy. We present applications and achievements of optically read out GEM-based detectors including high spatial resolution imaging and X-ray fluorescence measurements as an alternative readout approach for MPGDs. A detector concept for low intensity applications such as X-ray crystallography, which maximises detection efficiency with a thick conversion region but mitigates parallax-induced broadening is presented and beam monitoring capabilities of optical readout are explored. Augmenting high resolution 2D projections of particle tracks obtained with optical readout with timing information from fast photon detectors or transparent anodes for charge readout, 3D reconstruction of particle trajectories can be performed and permits the realisation of optically read out time projection chambers. Combining readily available high performance imaging sensors with compatible

  12. Particle identification via transition radiation and detectors

    International Nuclear Information System (INIS)

    Egorytchev, V.; Saveliev, V.; Aplin, S.J.

    2000-01-01

    Transition radiation detectors show great promise for the purposes of lepton identification in existing and future experiments in high-energy physics such as HERA-B, ATLAS, ALICE in high-luminosity environment. More high performance can be expected in low-luminosity conditions - neutrino experiments (NOMAD), and ideal condition for the use of transition radiation detectors in flying and space high-energy experiments (AMS). This paper discusses the practical theory of transition radiation, basic equation and algorithm suitable for detailed analysis of transition radiation and optimization of transition radiation detectors in the area of experimental high-energy physics. The results are based on detailed Monte Carlo simulation of transition radiation introduced in GEANT and experimental results

  13. Particle identification via transition radiation and detectors

    CERN Document Server

    Egorytchev, V; Aplin, S J

    2000-01-01

    Transition radiation detectors show great promise for the purposes of lepton identification in existing and future experiments in high- energy physics such as HERA-B, ATLAS, ALICE in high-luminosity environment. More high performance can be expected in low-luminosity conditions-neutrino experiments (NOMAD), and the ideal condition for the use of transition radiation detectors in flying and space high- energy experiments (AMS). This paper discusses the practical theory of transition radiation, basic equation and algorithm suitable for detailed analysis of transition radiation and optimization of transition radiation detectors in the area of experimental high- energy physics. The results are based on detailed Monte Carlo simulation of transition radiation introduced in GEANT and experimental results. (12 refs).

  14. Recent advancements in the development of radiation hard semiconductor detectors for S-LHC

    CERN Document Server

    Fretwurst, E; Al-Ajili, A A; Alfieri, G; Allport, P P; Artuso, M; Assouak, S; Avset, B S; Barabash, L; Barcz, A; Bates, R; Biagi, S F; Bilei, G M; Bisello, D; Blue, A; Blumenau, A; Boisvert, V; Bölla, G; Bondarenko, G B; Borchi, E; Borrello, L; Bortoletto, D; Boscardin, M; Bosisio, L; Bowcock, T J V; Brodbeck, T J; Broz, J; Bruzzi, M; Brzozowski, A; Buda, M; Buhmann, P; Buttar, C; Campabadal, F; Campbell, D; Candelori, A; Casse, G; Cavallini, A; Charron, S; Chilingarov, A G; Chren, D; Cindro, V; Collins, P; Coluccia, R; Contarato, D; Coutinho, J; Creanza, D; Cunningham, L; Dalla Betta, G F; Dawson, I; de Boer, Wim; De Palma, M; Demina, R; Dervan, P; Dittongo, S; Dolezal, Z; Dolgolenko, A; Eberlein, T; Eremin, V; Fall, C; Fasolo, F; Ferbel, T; Fizzotti, F; Fleta, C; Focardi, E; Forton, E; García, C; García-Navarro, J E; Gaubas, E; Genest, M H; Gill, K A; Giolo, K; Glaser, M; Gössling, C; Golovine, V; González-Sevilla, S; Gorelov,I; Goss, J; Gouldwell-Bates, A; Grégoire, G; Gregori, P; Grigoriev, E; Grillo, A A; Groza, A; Guskov, J; Haddad, L; Härkönen, J; Hauler, F; Hoeferkamp, M; Honniger, F; Horazdovsky, T; Horisberger, R P; Horn, M; Houdayer, A; Hourahine, B; Hughes, G; Ilyashenko, Yu S; Irmscher, K; Ivanov, A; Jarasiunas, K; Johansen, K M H; Jones, B K; Jones, R; Joram, C; Jungermann, L; Kalinina, E; Kaminski, P; Karpenko, A; Karpov, A; Kazlauskiene, V; Kazukauskas, V; Khivrich, V; Khomenkov, V P; Kierstead, J A; Klaiber Lodewigs, J M; Klingenberg, R; Kodys, P; Kohout, Z; Korjenevski, S; Koski, M; Kozlowski, R; Kozodaev, M; Kramberger, G; Krasel, O; Kuznetsov, A; Kwan, S; Lagomarsino, S; Lassila-Perini, K M; Lastovetsky, V F; Latino, G; Lazanu, I; Lazanu, S; Lebedev, A; Lebel, C; Leinonen, K; Leroy, C; Li, Z; Lindström, G; Linhart, V; Litovchenko, P G; Litovchenko, A P; Lo Giudice, A; Lozano, M; Luczynski, Z; Luukka, Panja; Macchiolo, A; Makarenko, L F; Mandic, I; Manfredotti, C; Manna, N; Martí i García, S; Marunko, S; Mathieson, K; Melone, J; Menichelli, D; Messineo, A; Metcalfe, J; Miglio, S; Mikuz, M; Miyamoto, J; Moll, M; Monakhov, E; Moscatelli, F; Naoumov, D; Nossarzhevska, E; Nysten, J; Olivero, P; O'Shea, V; Palviainen, T; Paolini, C; Parkes, C; Passeri, D; Pein, U; Pellegrini, G; Perera, L; Petasecca, M; Piemonte, C; Pignatel, G U; Pinho, N; Pintilie, I; Pintilie, L; Polivtsev, L; Polozov, P; Popa, A; Populea, J; Pospísil, S; Pozza, A; Radicci, V; Rafí, J M; Rando, R; Röder, R; Rohe, T; Ronchin, S; Rott, C; Roy, A; Ruzin, A; Sadrozinski, H F W; Sakalauskas, S; Scaringella, M; Schiavulli, L; Schnetzer, S; Schumm, B; Sciortino, S; Scorzoni, A; Segneri, G; Seidela, S; Seiden, A; Sellberg, G; Sellin, P J; Sentenac, D; Shipsey, I; Sícho, P; Sloan, T; Solar, M; Son, S; Sopko, B; Sopko, V; Spencer, N; Stahl, J; Stolze, D; Stone, R; Storasta, J; Strokan, N; Sudzius, M; Surma, B; Suvorov, A; Svensson, B G; Tipton, P; Tomasek, M; Tsvetkov, A; Tuominen, E; Tuovinen, E; Tuuva, T; Tylchin, M; Uebersee, H; Uher, J; Ullán, M; Vaitkus, J V; Velthuis, J; Verbitskaya, E; Vrba, V; Wagner, G; Wilhelm, I; Worm, S; Wright, V; Wunstorf, R; Yiuri, Y; Zabierowski, P; Zaluzhny, A; Zavrtanik, M; Zen, M; Zhukov, V; Zorzi, N

    2005-01-01

    The proposed luminosity upgrade of the Large Hadron Collider (S-LHC) at CERN will demand the innermost layers of the vertex detectors to sustain fluences of about 1016 hadrons/cm2. Due to the high multiplicity of tracks, the required spatial resolution and the extremely harsh radiation field new detector concepts and semiconductor materials have to be explored for a possible solution of this challenge. The CERN RD50 collaboration “Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders” has started in 2002 an R&D program for the development of detector technologies that will fulfill the requirements of the S-LHC. Different strategies are followed by RD50 to improve the radiation tolerance. These include the development of defect engineered silicon like Czochralski, epitaxial and oxygen-enriched silicon and of other semiconductor materials like SiC and GaN as well as extensive studies of the microscopic defects responsible for the degradation of irradiated sensors. Furthe...

  15. Precision synchrotron radiation detectors

    International Nuclear Information System (INIS)

    Levi, M.; Rouse, F.; Butler, J.

    1989-03-01

    Precision detectors to measure synchrotron radiation beam positions have been designed and installed as part of beam energy spectrometers at the Stanford Linear Collider (SLC). The distance between pairs of synchrotron radiation beams is measured absolutely to better than 28 /mu/m on a pulse-to-pulse basis. This contributes less than 5 MeV to the error in the measurement of SLC beam energies (approximately 50 GeV). A system of high-resolution video cameras viewing precisely-aligned fiducial wire arrays overlaying phosphorescent screens has achieved this accuracy. Also, detectors of synchrotron radiation using the charge developed by the ejection of Compton-recoil electrons from an array of fine wires are being developed. 4 refs., 5 figs., 1 tab

  16. Radiation detector. [100 A

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P D; Hollands, D V

    1975-12-04

    A radiation detector is described in which the radiation is led to a sensor via a 100 A thick gold film filter, which reduces the infrared components of the irradiation to a greater extent than the ultra-violet component reaching the sensor.

  17. Radiation detector arrangements and methods

    International Nuclear Information System (INIS)

    Jackson, J.

    1989-01-01

    The patent describes a radiation detector arrangement. It comprises at least one detector element in the form of a temperature-sensitive resistor whose electrical resistance changes in response to radiation incident on the detector element, the resistor having a high positive temperature coefficient of electrical resistance at a transition in its electrical conductance, circuit means for applying a voltage across the resistor during operation of the detector arrangement, and temperature-regulation means for regulating the temperature of the resistor so as to operate the resistor in the transition, characterised in that the temperature-regulation means comprises the resistor and the circuit means which passes sufficient current through the resistor by resistance heating to a position in the transition at which a further increase in its temperature in response to incident radiation reduces the resistance heating by reducing the current, thereby stabilizing the temperature of the resistor at the position. The positive temperature coefficient at the position being sufficiently high that the change in the resistance heating produced by a change in the temperature of the resistor at the position is larger than a change in power of the incident radiation required to produce that same change in temperature of the resistor in the absence of any change in resistance heating

  18. Notification determining technical standards concerning prevention of radiation injuries by electron capture detectors for gas chromatography

    International Nuclear Information System (INIS)

    1981-01-01

    This rule is established under the provisions of the law on the prevention of radiation injuries by radioisotopes, the ordinance and the regulation for the execution of the law. This rule is applied to electron capture detectors for gas chromatography under the law. Basic terms are defined, such as detector radiation source, detector container and carrier gas. The detectors shall consist of detector radiation sources and containers, and the containers must be such that the radiation sources can not be easily taken away and never cause the danger to fall off. The induction and discharge mouths of the detector containers shall be shut tightly with caps, etc. The main structures and radiation sources of detectors shall be made of materials, which are difficult to corrode, and do not melt and easily cause chemical change below 800 deg. C. Detector radiation sources shall be made of metals plated with nickel 63 less than 20 milli-curie. The radiation dose rate on the surface of a detector shall be shielded to less than 0.06 milli-rem an hour. The temperature of detectors and carrier gas shall not exceed 350 deg. C. Corrosive gas shall not be used as carrier gas. The period of effective indication is 5 years. The method of washing, and the conditions of leak, heat-resistance and shock-resistance examinations are defined, respectively. (Okada, K.)

  19. Recent developments in radiation detectors and instruments

    International Nuclear Information System (INIS)

    Das, Debashis

    2016-01-01

    Radiation detector is the key component in precise and accurate measurement of the nuclear radiations. The detectors deployed for radiation measurements in broadly classified sectors of Energy, Security, Discovery Science and Health and Environments are in general specific to their applications. The nuclear reactors as well as the fuel processing including waste management in energy sector require wide range/variety of detectors and the instruments for safe and precise generation of power. The security sector has gained importance in radiation monitoring in the present security perspective and there are many challenges in development of detector technology. The Discovery Science or the mega science projects viz CERN, Fermilab, GANIL, INO, MACE telescope, ITER etc have continuously generated new demand on detector related technologies that have been also found to be useful in other applications. Similarly, the health and environment monitoring have been also evolving with new technologies and techniques to address the requirement's arising in projects of new nuclear programs

  20. SENTIRAD-An innovative personal radiation detector based on a scintillation detector and a silicon photomultiplier

    International Nuclear Information System (INIS)

    Osovizky, A.; Ginzburg, D.; Manor, A.; Seif, R.; Ghelman, M.; Cohen-Zada, I.; Ellenbogen, M.; Bronfenmakher, V.; Pushkarsky, V.; Gonen, E.; Mazor, T.; Cohen, Y.

    2011-01-01

    The alarming personal radiation detector (PRD) is a device intended for Homeland Security (HLS) applications. This portable device is designed to be worn or carried by security personnel to detect photon-emitting radioactive materials for the purpose of crime prevention. PRD is required to meet the scope of specifications defined by various HLS standards for radiation detection. It is mandatory that the device be sensitive and simultaneously small, pocket-sized, of robust mechanical design and carriable on the user's body. To serve these specialized purposes and requirements, we developed the SENTIRAD, a new radiation detector designed to meet the performance criteria established for counterterrorist applications. SENTIRAD is the first commercially available PRD based on a CsI(Tl) scintillation crystal that is optically coupled with a silicon photomultiplier (SiPM) serving as a light sensor. The rapidly developing technology of SiPM, a multipixel semiconductor photodiode that operates in Geiger mode, has been thoroughly investigated in previous studies. This paper presents the design considerations, constraints and radiological performance relating to the SENTIRAD radiation sensor.

  1. Charge collection efficiency in a semiconductor radiation detector with a non-constant electric field

    International Nuclear Information System (INIS)

    Shah, K.S.; Lund, J.C.; Olschner, F.

    1990-01-01

    The development of improved semiconductor radiation detectors would be facilitated by a quantitative model that predicts the performance of these detectors as a function of material characteristics and device operating parameters. An accurate prediction of the pulse height spectrum from a radiation detector can be made if both the noise and the charge collection properties of the detector are understood. The noise characteristics of semiconductor radiation detectors have been extensively studied. The effect of noise can be closely simulated by convoluting the noise-free pulse height spectrum with a Gaussian function. Distortion of semiconductor detector's pulse height spectrum from charge collection effects is more complex than the effects of noise and is more difficult to predict. To compute these distortions it is necessary to know how the charge collection efficiency η varies as a function of position within the detector x. These effects are shown. This problem has been previously solved for planar detectors with a constant electric field, for the case of spherical detectors, and for coaxial detectors. In this paper the authors describe a more general solution to the charge collection problem which includes the case of a non-constant electric field in a planar geometry

  2. Radiation hard silicon particle detectors for HL-LHC—RD50 status report

    Energy Technology Data Exchange (ETDEWEB)

    Terzo, S., E-mail: Stefano.Terzo@mpp.mpg.de

    2017-02-11

    It is foreseen to significantly increase the luminosity of the LHC by upgrading towards the HL-LHC (High Luminosity LHC). The Phase-II-Upgrade scheduled for 2024 will mean unprecedented radiation levels, way beyond the limits of the silicon trackers currently employed. All-silicon central trackers are being studied in ATLAS, CMS and LHCb, with extremely radiation hard silicon sensors to be employed on the innermost layers. Within the RD50 Collaboration, a massive R&D program is underway across experimental boundaries to develop silicon sensors with sufficient radiation tolerance. We will present results of several detector technologies and silicon materials at radiation levels corresponding to HL-LHC fluences. Based on these results, we will give recommendations for the silicon detectors to be used at the different radii of tracking systems in the LHC detector upgrades. In order to complement the measurements, we also perform detailed simulation studies of the sensors. - Highlights: • The RD50 collaboration investigates the radiation hardness of silicon sensors. • Different approaches to simulate the detector response after irradiation are shown. • HV-CMOS are cost-effective solution for the outer pixel layers at HL-LHC. • 3D and thin planar sensors with slim edges are solutions for innermost layers at HL-LHC. • Sensors with intrinsic gain are investigated to develop ultra-fast silicon detectors.

  3. Solid state detectors for neutron radiation monitoring in fusion facilities

    International Nuclear Information System (INIS)

    Gómez-Ros, J.M.

    2014-01-01

    The purpose of this communication is to summarize the main solid state based detectors proposed for neutron diagnostic in fusion applications and their applicability under the required harsh conditions in terms of intense radiation, high temperature and available space restrictions. Activation systems, semiconductor based detectors, luminescent materials and Cerenkov fibre optics sensors (C-FOS) are the main devices that are described. - Highlights: • A state-of-the-art summary of solid state based detectors are described. • Conditions and restrictions for their applicability are described. • A list of the 38 more relevant references has been included

  4. Photodiodes utilization as ionizing radiation detectors

    International Nuclear Information System (INIS)

    Khoury, H.J.; Melo, F.A. de

    1987-01-01

    The response of photodiodes to α and γ radiation is studied, using for α spectrometry measures and for γ radiation dosimetry. Therefore, the response of BPY-12 photodiodes as α particle detector is first studied. The results show that the response is linear with the energy of incidence radiation, one resolution 25Kev for energy of 5,4 MeV from 241 Am. For dosimetric measures, the response of SHF-206 photodiodes, when exposed at γ radiation is studied, and the results show taht the response of this detector is linear with the dose ratio, proving its practicability in γ radiation dosimetry. (C.G.C.) [pt

  5. Radiation hardness of silicon detectors manufactured on epitaxial material and FZ bulk enriched with oxygen, carbon, tin and platinum

    CERN Document Server

    Ruzin, A; Glaser, M; Lemeilleur, F; Talamonti, R; Watts, S; Zanet, A

    1999-01-01

    Recent results on the radiation hardness of silicon detectors fabricated on epitaxial and float zone bulk silicon enriched by various impurities, such as carbon, oxygen, tin and platinum are reported. A new methodology of measurements of electrical properties of the devices has been utilized in the experiment. It has been shown that in the case of irradiation by protons, oxygen enriched silicon has better radiation hardness than standard float zone silicon. The carbon enriched silicon detectors, on the other hand, exhibited significantly inferior radiation hardness compared to standard detectors. This study shows for the first time, a violation of the widely used normalization technique of the various particle irradiations by NIEL coefficients. The study has been carried out in the framework of the RD48 (ROSE) collaboration, which studies the radiation hardening of silicon detectors. (5 refs).

  6. Radiation detector system having heat pipe based cooling

    Science.gov (United States)

    Iwanczyk, Jan S.; Saveliev, Valeri D.; Barkan, Shaul

    2006-10-31

    A radiation detector system having a heat pipe based cooling. The radiation detector system includes a radiation detector thermally coupled to a thermo electric cooler (TEC). The TEC cools down the radiation detector, whereby heat is generated by the TEC. A heat removal device dissipates the heat generated by the TEC to surrounding environment. A heat pipe has a first end thermally coupled to the TEC to receive the heat generated by the TEC, and a second end thermally coupled to the heat removal device. The heat pipe transfers the heat generated by the TEC from the first end to the second end to be removed by the heat removal device.

  7. CVD diamond detectors for ionizing radiation

    Science.gov (United States)

    Friedl, M.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knöpfle, K. T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P. F.; Manfredotti, C.; Marshall, R. D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L. S.; Palmieri, V. G.; Pernegger, H.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J. L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.; RD42 Collaboration

    1999-10-01

    In future HEP accelerators, such as the LHC (CERN), detectors and electronics in the vertex region of the experiments will suffer from extreme radiation. Thus radiation hardness is required for both detectors and electronics to survive in this harsh environment. CVD diamond, which is investigated by the RD42 Collaboration at CERN, can meet these requirements. Samples of up to 2×4 cm2 have been grown and refined for better charge collection properties, which are measured with a β source or in a testbeam. A large number of diamond samples has been irradiated with hadrons to fluences of up to 5×10 15 cm-2 to study the effects of radiation. Both strip and pixel detectors were prepared in various geometries. Samples with strip metallization have been tested with both slow and fast readout electronics, and the first diamond pixel detector proved fully functional with LHC electronics.

  8. Neutron spectrometry by diamond detector for nuclear radiation

    International Nuclear Information System (INIS)

    Kozlov, S.F.; Konorova, E.A.; Barinov, A.L.; Jarkov, V.P.

    1975-01-01

    Experiments on fast neutron spectrometry using the nuclear radiation diamond detector inside a horizontal channel of a water-cooled and water-moderated reactor are described. It is shown that the diamond detector enables neutron spectra to be measured within the energy range of 0.3 to 10 MeV against reactor gamma-radiation background and has radiation resistance higher than that of conventional semiconductor detectors. (U.S.)

  9. Study of detectors in beta radiation fields

    International Nuclear Information System (INIS)

    Albuquerque, M. da P.P.; Xavier, M.; Caldas, L.V.E.

    1987-01-01

    Several commercial detectors used with gamma or X radiation are studied. Their sensibility and energetic dependence are analysed in exposures of beta radiation fields. A comparative evaluation with the reference detector (the extrapolation chamber) is presented. (M.A.C.) [pt

  10. Development of innovative silicon radiation detectors

    CERN Document Server

    Balbuena, JuanPablo

    Silicon radiation detectors fabricated at the IMB-CNM (CSIC) Clean Room facilities using the most innovative techniques in detector technology are presented in this thesis. TCAD simulation comprises an important part in this work as becomes an essential tool to achieve exhaustive performance information of modelled detectors prior their fabrication and subsequent electrical characterization. Radiation tolerance is also investigated in this work using TCAD simulations through the potential and electric field distributions, leakage current and capacitance characteristics and the response of the detectors to the pass of different particles for charge collection efficiencies. Silicon detectors investigated in this thesis were developed for specific projects but also for applications in experiments which can benefit from their improved characteristics, as described in Chapter 1. Double-sided double type columns 3D (3D-DDTC) detectors have been developed under the NEWATLASPIXEL project in the framework of the CERN ...

  11. Radiation-damage studies, irradiations and high-dose dosimetry for LHC detectors

    CERN Document Server

    Coninckx, F; León-Florián, E; Leutz, H; Schönbacher, Helmut; Sonderegger, P; Tavlet, Marc; Sopko, B; Henschel, H; Schmidt, H U; Boden, A; Bräunig, D; Wulf, F; Cramariuc, R; Ilie, D; Fattibene, P; Onori, S; Miljanic, S; Paic, G; Razen, B; Razem, D; Rendic, D; CERN. Geneva. Detector Research and Development Committee

    1991-01-01

    The proposal is divided into a main project and special projects. The main project consists of a service similar to the one given in the past to accelerator construction projects at CERN (ISR,SPS,LEP) on high-dose dosimetry, material irradiations, irradiations tests, standardization of test procedures and data compilations. Large experience in this field and numerous radiation damage test data of insulating and structural materials are available. The special projects cover three topics which are of specific interest for LHC detector physicists and engineers at CERN and in other high energy physics institutes, namely: Radiation effects in scintillators; Selection of radiation hard optical fibres for data transmission; and Selection and testing of radiation hard electronic components.

  12. Radiation effects on light sources and detectors

    International Nuclear Information System (INIS)

    Barnes, C.E.

    1985-01-01

    The rapidly expanding field of optoelectronics includes a wide variety of both military and non-military applications in which the systems must meet radiation exposure requirements. Herein, we review the work on radiation effects on sources and detectors for such optoelectronic systems. For sources the principal problem is permanent damage-induced light output degradation, while for detectors it is ionizing radiation-induced photocurrents

  13. Detectors for Particle Radiation

    Science.gov (United States)

    Kleinknecht, Konrad

    1999-01-01

    This textbook provides a clear, concise and comprehensive review of the physical principles behind the devices used to detect charged particles and gamma rays, and the construction and performance of these many different types of detectors. Detectors for high-energy particles and radiation are used in many areas of science, especially particle physics and nuclear physics experiments, nuclear medicine, cosmic ray measurements, space sciences and geological exploration. This second edition includes all the latest developments in detector technology, including several new chapters covering micro-strip gas chambers, silicion strip detectors and CCDs, scintillating fibers, shower detectors using noble liquid gases, and compensating calorimeters for hadronic showers. This well-illustrated textbook contains examples from the many areas in science in which these detectors are used. It provides both a coursebook for students in physics, and a useful introduction for researchers in other fields.

  14. Monitoring radiation damage in the ATLAS pixel detector

    CERN Document Server

    Schorlemmer, André Lukas; Quadt, Arnulf; Große-Knetter, Jörn; Rembser, Christoph; Di Girolamo, Beniamino

    2014-11-05

    Radiation hardness is one of the most important features of the ATLAS pixel detector in order to ensure a good performance and a long lifetime. Monitoring of radiation damage is crucial in order to assess and predict the expected performance of the detector. Key values for the assessment of radiation damage in silicon, such as the depletion voltage and depletion depth in the sensors, are measured on a regular basis during operations. This thesis summarises the monitoring program that is conducted in order to assess the impact of radiation damage and compares it to model predictions. In addition, the physics performance of the ATLAS detector highly depends on the amount of disabled modules in the ATLAS pixel detector. A worrying amount of module failures was observed during run I. Thus it was decided to recover repairable modules during the long shutdown (LS1) by extracting the pixel detector. The impact of the module repairs and module failures on the detector performance is analysed in this thesis.

  15. CVD diamond detectors for ionizing radiation

    CERN Document Server

    Friedl, M; Bauer, C; Berfermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernegger, H; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Tapper, R J; Tesarek, R J; Thomson, G B; Trawick, M L; Trischuk, W; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zöller, M

    1999-01-01

    In future HEP accelerators, such as the LHC (CERN), detectors and electronics in the vertex region of the experiments will suffer from extreme radiation. Thus radiation hardness is required for both detectors and electronics to survive in this harsh environment. CVD diamond, which is investigated by the RD42 Collaboration at CERN, can meet these requirements. Samples of up to 2*4 cm/sup 2/ have been grown and refined for better charge collection properties, which are measured with a beta source or in a test beam. A large number of diamond samples has been irradiated with hadrons to fluences of up to 5*10/sup 15/ cm/sup -2/ to study the effects of radiation. Both strip and pixel detectors were prepared in various geometries. Samples with strip metallization have been tested with both slow and fast readout electronics, and the first diamond pixel detector proved fully functional with LHC electronics. (16 refs).

  16. CVD diamond detectors for ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Friedl, M. E-mail: markus.friedl@cern.ch; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernegger, H.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R.J.; Tesarek, R.; Thomson, G.B.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M

    1999-10-01

    In future HEP accelerators, such as the LHC (CERN), detectors and electronics in the vertex region of the experiments will suffer from extreme radiation. Thus radiation hardness is required for both detectors and electronics to survive in this harsh environment. CVD diamond, which is investigated by the RD42 Collaboration at CERN, can meet these requirements. Samples of up to 2x4 cm{sup 2} have been grown and refined for better charge collection properties, which are measured with a {beta} source or in a test beam. A large number of diamond samples has been irradiated with hadrons to fluences of up to 5x10{sup 15} cm{sup -2} to study the effects of radiation. Both strip and pixel detectors were prepared in various geometries. Samples with strip metallization have been tested with both slow and fast readout electronics, and the first diamond pixel detector proved fully functional with LHC electronics. (author)

  17. Radiation hard silicon microstrip detectors for use in ATLAS at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, Lars Gimmestad

    2005-07-01

    The Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) will accelerate protons in colliding beams to a center of mass energy of 14 TeV at very high luminosities. The ATLAS detector is being built to explore the physics in this unprecedented energy range. Tracking of charged particles in high-energy physics (HEP) experiments requires a high spatial resolution and fast signal readout, all with as little material as possible. Silicon microstrip detectors meet these requirements well and have been chosen for the Semiconductor Tracker (SCT) which is part of the inner tracking system of ATLAS and has a total area of 61 m2. During the 10 years of operation at LHC, the total fluence received by the detectors is sufficiently large that they will suffer a severe degradation from radiation induced damage. The damage affects both the physics performance of the detectors as well as their operability and a great challenge has been to develop radiation hard detectors for this environment. An extensive irradiation programme has been carried out where detectors of various designs, including defect engineering by oxygen enriched silicon, have been irradiated to the expected fluence. A subsequent thermal annealing period is included to account for a realistic annual maintenance schedule at room temperature, during which the radiation induced defects alter the detector properties significantly. This thesis presents work that has been carried out in the Bergen ATLAS group with results both from the irradiation programme and from detector testing during the module production. (Author)

  18. Radiation hard silicon microstrip detectors for use in ATLAS at CERN

    International Nuclear Information System (INIS)

    Johansen, Lars Gimmestad

    2005-06-01

    The Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) will accelerate protons in colliding beams to a center of mass energy of 14 TeV at very high luminosities. The ATLAS detector is being built to explore the physics in this unprecedented energy range. Tracking of charged particles in high-energy physics (HEP) experiments requires a high spatial resolution and fast signal readout, all with as little material as possible. Silicon microstrip detectors meet these requirements well and have been chosen for the Semiconductor Tracker (SCT) which is part of the inner tracking system of ATLAS and has a total area of 61 m2. During the 10 years of operation at LHC, the total fluence received by the detectors is sufficiently large that they will suffer a severe degradation from radiation induced damage. The damage affects both the physics performance of the detectors as well as their operability and a great challenge has been to develop radiation hard detectors for this environment. An extensive irradiation programme has been carried out where detectors of various designs, including defect engineering by oxygen enriched silicon, have been irradiated to the expected fluence. A subsequent thermal annealing period is included to account for a realistic annual maintenance schedule at room temperature, during which the radiation induced defects alter the detector properties significantly. This thesis presents work that has been carried out in the Bergen ATLAS group with results both from the irradiation programme and from detector testing during the module production. (Author)

  19. Mixed ionic-electronic conductor-based radiation detectors and methods of fabrication

    Science.gov (United States)

    Conway, Adam; Beck, Patrick R; Graff, Robert T; Nelson, Art; Nikolic, Rebecca J; Payne, Stephen A; Voss, Lars; Kim, Hadong

    2015-04-07

    A method of fabricating a mixed ionic-electronic conductor (e.g. TlBr)-based radiation detector having halide-treated surfaces and associated methods of fabrication, which controls polarization of the mixed ionic-electronic MIEC material to improve stability and operational lifetime.

  20. Effects of ionizing radiation on cryogenic infrared detectors

    Science.gov (United States)

    Moseley, S. H.; Silverberg, R. F.; Lakew, B.

    1989-01-01

    The Diffuse Infrared Background Experiment (DIRBE) is one of three experiments to be carried aboard the Cosmic Background Explorer (COBE) satellite scheduled to be launched by NASA on a Delta rocket in 1989. The DIRBE is a cryogenic absolute photometer operating in a liquid helium dewar at 1.5 K. Photometric stability is a principal requirement for achieving the scientific objectives of this experiment. The Infrared Astronomy Satellite (IRAS), launched in 1983, which used detectors similar to those in DIRBE, revealed substantial changes in detector responsivity following exposure to ionizing radiation encountered on passage through the South Atlantic Anomaly (SAA). Since the COBE will use the same 900 Km sun-synchronous orbit as IRAS, ionizing radiation-induced performance changes in the detectors were a major concern. Here, ionizing radiation tests carried out on all the DIRBE photodetectors are reported. Responsivity changes following exposure to gamma rays, protons, and alpha particle are discussed. The detector performance was monitored following a simulated entire mission life dose. In addition, the response of the detectors to individual particle interactions was measured. The InSb photovoltaic detectors and the Blocked Impurity Band (BIB) detectors revealed no significant change in responsivity following radiation exposure. The Ge:Ga detectors show large effects which were greatly reduced by proper thermal annealing.

  1. General gamma-radiation test of TGC detectors

    CERN Document Server

    Smakhtin, V P

    2004-01-01

    The TGC detectors are expected to provide the Muon trigger for the ATLAS detector in the forward region of the ATLAS Muon Spectrometer. The TGC detectors have to provide a trigger signal within 25 ns of the LHC accelerator bunch spacing, with an efficiency exceeding 95%, while exposed to an effective)photon and neutron background ranging from 30 to 150 Hz/cm/sup 2/. In order to test TGC detectors in high rate environment every detector was irradiated at 2500 Cu Co-60 source in Radiation Facility of Weizmann Institute of Science at nominal operating voltage and at photon rate several times above the expected background. This radiation test was succeeded in diagnostics of the hot spots inside detectors. The present publication refers to the test results of 800 TGC detectors produced in the Weizmann Institute of Science. (1 refs).

  2. Radiation damage studies for the DOe silicon detector

    International Nuclear Information System (INIS)

    Lehner, Frank

    2004-01-01

    We report on irradiation studies performed on spare production silicon detector modules for the current DOe silicon detector. The lifetime expectations due to radiation damage effects of the existing silicon detector are reviewed. A new upgrade project was started with the goal of a complete replacement of the existing silicon detector. In that context, several investigations on the radiation hardness of new prototype silicon microstrip detectors were carried out. The irradiation on different detector types was performed with 10 MeV protons up to fluences of 10 14 p/cm 2 at the J.R. Mcdonald Laboratory at Kansas State University. The flux calibration was carefully checked using different normalisation techniques. As a result, we observe roughly 40-50% less radiation damage in silicon for 10 MeV p exposure than it is expected by the predicted NIEL scaling

  3. Superconductive tunnel structures as radiation detectors

    International Nuclear Information System (INIS)

    Barone, A.; Gray, K.E.

    1985-08-01

    A brief review is given on various aspects of the potential of superconducting tunnel junctions as detectors for atomic and nuclear radiations. On the basis of recent results main advantages and drawbacks are indicated providing a preliminary comparison with the presently used semiconductor detectors. The basic ideas underlying the physics of the interaction of nuclear particles and other radiations with superconducting junctions are outlined. 9 refs., 1 tab

  4. X- and gamma-ray N+PP+ silicon detectors with high radiation resistance

    International Nuclear Information System (INIS)

    Petris, M.; Ruscu, R.; Moraru, R.; Cimpoca, V.

    1998-01-01

    We have investigated the use of p-type silicon detectors as starting material for X-and gamma-ray detectors because of several potential benefits it would bring: 1. high purity p-type silicon grown by the float-zone process exhibits better radial dopant uniformity than n-type float-zone silicon; 2. it is free of radiation damage due to the neutron transmutation doping process and behaves better in a radiation field because mainly acceptor like centers are created through the exposure and the bulk material type inversion does not occur as in the n-type silicon. But the p-type silicon, in combination with a passivating layer of silicon dioxide, leads to a more complex detector layout since the positive charge in the oxide causes an inversion in the surface layer under the silicon dioxide. Consequently, it would be expected that N + P diodes have a higher leakage current than P + N ones. All these facts have been demonstrated experimentally. These features set stringent requirements for the technology of p-type silicon detectors. Our work presents two new geometries and an improved technology for p-type high resistivity material to obtain low noise radiation detectors. Test structures were characterized before and after the gamma exposure with a cumulative dose in the range 10 4 - 5 x 10 6 rad ( 60 Co). Results indicate that proposed structures and their technology enable the development of reliable N + PP + silicon detectors. For some samples (0.8 - 12 mm 2 ), extremely low reverse currents were obtained and, in combination with a low noise charge preamplifier, the splitting of 241 Am X-ray lines was possible and also the Mn Kα line (5.9 keV) was extracted from the noise with a 1.9 keV FWHM at the room temperature. An experimental model of a nuclear probe based on these diodes was designed for X-ray detection applications. (authors)

  5. Method and circuit for stabilizing conversion gain of radiation detectors of a radiation detection system

    International Nuclear Information System (INIS)

    Stoub, E.W.

    1986-01-01

    A method is described for calibrating the gain of an array of radiation detectors of a radiation detection system comprising the steps of: (a) measuring in parallel for each radiation detector using a predetermined calibration point the energy map status, thereby obtaining an energy response vector whose elements correspond to the individual output of each radiation detector, each predetermined calibration point being a prescribed location corresponding to one of the radiation detectors; (b) multiplying that energy response vector with a predetermined deconvolution matrix, the deconvolution matrix being the inversion of a contribution matrix containing matrix elements C/sub IJ/, each such matrix element C/sub IJ/ of the contribution matrix representing the relative contribution level of a radiation detector j of the detection system for a point radiation source placed at a location i, thereby obtaining a gain vector product for the radiation detectors; (c) adjusting the gains of the radiation detectors with respect to the gain vector product such that a unity gain vector is essentially obtained; (d) measuring again the energy map status according to step (a); and (e) if the energy map status fails to essentially produce a unity gain vector repeat steps (a) to (d) until the energy map status substantially corresponds to unity

  6. Self-powered radiation detector

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Todt, W.H.

    1979-01-01

    Self-powered gamma radiation detector composed of a conducting emitter surrounded by an insulating medium and a conducting tubular collector, the emitter being a hollow tube containing an electrical insulator [fr

  7. VeriTainer radiation detector for intermodal shipping containers

    International Nuclear Information System (INIS)

    Redus, R.H.; Alioto, M.; Sperry, D.; Pantazis, T.

    2007-01-01

    The VeriSpreader TM radiation detection system will monitor every container passing through a shipping terminal without impeding the flow of commerce by making the radiation measurements during normal container handling. This is accomplished by integrating neutron and spectroscopic γ-ray detectors into a container crane spreader bar, the part of the crane that directly engages the intermodal shipping containers while moving from ship to shore and vice versa. The use of a spectroscopic γ-detector reduces the rate of nuisance alarms due to naturally occurring radioactive material (NORM). The combination of γ and neutron detection reduces the effectiveness of shielding and countermeasures. The challenges in this spreader bar-based approach arise from the harsh environment, particularly the mechanical shock and the vibration of the moving spreader bar, since the measurement is taken while the container is moving. The electrical interfaces in the port environment, from the crane to a central monitoring office, present further challenges. It is the packaging, electronic interfaces, and data processing software that distinguish this system, which is based on conventional radiation sensors. The core of the system is Amptek's GAMMA-RAD, which integrates a ruggedized scintillator/PMT, digital pulse shaping electronics, electronics for the neutron detector, power supplies, and an Ethernet interface. The design of the VeriTainer system and results from both the laboratory and a proof-of-concept test at the Port of Oakland, California will be presented

  8. Differential Detector for Measuring Radiation Fields

    International Nuclear Information System (INIS)

    Broide, A.; Marcus, E.; Brandys, I.; Schwartz, A.; Wengrowicz, U.; Levinson, S.; Seif, R.; Sattinger, D.; Kadmon, Y.; Tal, N.

    2004-01-01

    In case of a nuclear accident, it is essential to determine the source of radioactive contamination in order to analyze the risk to the environment and to the population. The radiation source may be a radioactive plume on the air or an area on the ground contaminated with radionuclides. Most commercial radiation detectors measure only the radiation field intensity but are unable to differentiate between the radiation sources. Consequently, this limitation causes a real problem in analyzing the potential risk to the near-by environment, since there is no data concerning the contamination ratios in the air and on the ground and this prevents us from taking the required steps to deal with the radiation event. This work presents a GM-tube-based Differential Detector, which enables to determine the source of contamination

  9. Degradation of silicon AC-coupled microstrip detectors induced by radiation

    Science.gov (United States)

    Bacchetta, N.; Bisello, D.; Canali, C.; Fuochi, P. G.; Gotra, Y.; Paccagnella, A.; Verzellesi, G.

    1993-12-01

    Results are presented showing the radiation response of AC-coupled FOXFET biased microstrip detectors and related test patterns to be used in the microvertex detector of the CDF experiment at Fermi National Laboratory. Radiation tolerance of detectors to gamma and proton irradiation has been tested, and the radiation-induced variations of the DC electrical parameters have been analyzed. The long-term postirradiation behavior of detector characteristics has been studied, and the relevant room-temperature annealing phenomena have been examined. The main radiation damage effects after gamma or proton irradiation of FOXFET biased microstrip detectors consist of an increase in the total leakage current, while both the detector dynamic resistance and FOXFET switching voltage decrease.

  10. Hybrid anode for semiconductor radiation detectors

    Science.gov (United States)

    Yang, Ge; Bolotnikov, Aleksey E; Camarda, Guiseppe; Cui, Yonggang; Hossain, Anwar; Kim, Ki Hyun; James, Ralph B

    2013-11-19

    The present invention relates to a novel hybrid anode configuration for a radiation detector that effectively reduces the edge effect of surface defects on the internal electric field in compound semiconductor detectors by focusing the internal electric field of the detector and redirecting drifting carriers away from the side surfaces of the semiconductor toward the collection electrode(s).

  11. Radiation-hardened optoelectronic components: detectors

    International Nuclear Information System (INIS)

    Wiczer, J.J.

    1986-01-01

    In this talk, we will survey recent research in the area of radiation hardened optical detectors. We have studied conventional silicon photodiode structures, special radiation hardened silicon photodiodes, and special double heterojunction AlGaAs/GaAs photodiodes in neutron, gamma, pulsed x-ray and charged particle environments. We will present results of our work and summarize other research in this area. Our studies have shown that detectors can be made to function acceptably after exposures to neutron fluences of 10 15 n/cm 2 , total dose gamma exposures of 10 8 rad (Si), and flash x-ray environments of 10 8 rad/sec (Si). We will describe detector structures that can operate through these conditions, pre-rad and post-rad operational characteristics, and experimental conditions that produced these results. 23 refs., 10 figs., 1 tab

  12. Circuitry for use with an ionizing-radiation detector

    International Nuclear Information System (INIS)

    Marshall, J.H. III; Harrington, T.M.

    1976-01-01

    An improved system of circuitry for use in combination with an ionizing-radiation detector over a wide range of radiation levels includes a current-to-frequency converter together with a digital data processor for respectively producing and measuring a pulse repetition frequency which is proportional to the output current of the ionizing-radiation detector, a dc-to-dc converter for providing closely regulated operating voltages from a rechargeable battery and a bias supply for providing high voltage to the ionization chamber. The ionizing-radiation detector operating as a part of this system produces a signal responsive to the level of ionizing radiation in the vicinity of the detector, and this signal is converted into a pulse frequency which will vary in direct proportion to such level of ionizing-radiation. The data processor, by counting the number of pulses from the converter over a selected integration interval, provides a digital indication of radiation dose rate, and by accumulating the total of all such pulses provides a digital indication of total integrated dose. Ordinary frequency-to-voltage conversion devices or digital display techniques can be used as a means for providing audible and visible indications of dose and dose-rate levels

  13. Nuclear radiation-warning detector that measures impedance

    Science.gov (United States)

    Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven

    2013-06-04

    This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.

  14. Flame detector operable in presence of proton radiation

    Science.gov (United States)

    Walker, D. J.; Turnage, J. E.; Linford, R. M. F.; Cornish, S. D. (Inventor)

    1974-01-01

    A detector of ultraviolet radiation for operation in a space vehicle which orbits through high intensity radiation areas is described. Two identical ultraviolet sensor tubes are mounted within a shield which limits to acceptable levels the amount of proton radiation reaching the sensor tubes. The shield has an opening which permits ultraviolet radiation to reach one of the sensing tubes. The shield keeps ultraviolet radiation from reaching the other sensor tube, designated the reference tube. The circuitry of the detector subtracts the output of the reference tube from the output of the sensing tube, and any portion of the output of the sensing tube which is due to proton radiation is offset by the output of the reference tube. A delay circuit in the detector prevents false alarms by keeping statistical variations in the proton radiation sensed by the two sensor tubes from developing an output signal.

  15. Radiation effects in IRAS extrinsic infrared detectors

    Science.gov (United States)

    Varnell, L.; Langford, D. E.

    1982-01-01

    During the calibration and testing of the Infrared Astronomy Satellite (IRAS) focal plane, it was observed that the extrinsic photoconductor detectors were affected by gamma radiation at dose levels of the order of one rad. Since the flight environment will subject the focal plane to dose levels of this order from protons in single pass through the South Atlantic Anomaly, an extensive program of radiation tests was carried out to measure the radiation effects and to devise a method to counteract these effects. The effects observed after irradiation are increased responsivity, noise, and rate of spiking of the detectors after gamma-ray doses of less than 0.1 rad. The detectors can be returned almost to pre-irradiation performance by increasing the detector bias to breakdown and allowing a large current to flow for several minutes. No adverse effects on the detectors have been observed from this bias boost, and this technique will be used for IRAS with frequent calibration to ensure the accuracy of observations made with the instrument.

  16. Temperature effects on radiation damage in plastic detectors

    International Nuclear Information System (INIS)

    Mendoza A, D.

    1996-01-01

    The objective of present work was to study the temperature effect on radiation damage registration in the structure of a Solid State Nuclear Track Detector of the type CR-39. In order to study the radiation damage as a function of irradiation temperature, sheets of CR-39 detectors were irradiated with electron beams, simulating the interaction of positive ions. CR-39 detectors were maintained at a constant temperature from room temperature up to 373 K during irradiation. Two techniques were used from analyzing changes in the detector structure: Electronic Paramagnetic Resonance (EPR) and Infrared Spectroscopy (IR). It was found by EPR analysis that the amount of free radicals decrease as irradiation temperature increases. The IR spectrums show yield of new functional group identified as an hydroxyl group (OH). A proposed model of interaction of radiation with CR-39 detectors is discussed. (Author)

  17. Next Generation Semiconductor-Based Radiation Detectors Using Cadmium Magnesium Telluride

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, Sudhir B [Brimrose Technology Corporation, Sparks Glencoe, MD (United States); Kutcher, Susan W [Brimrose Technology Corporation, Sparks Glencoe, MD (United States); Palsoz, Witold [Brimrose Technology Corporation, Sparks Glencoe, MD (United States); Berding, Martha [SRI International, Menlo Park, CA (United States); Burger, Arnold [Brimrose Technology Corporation, Sparks Glencoe, MD (United States)

    2014-11-17

    The primary objective of Phase I was to perform extensive studies on the purification, crystal growth and annealing procedures of CdMgTe to gain a clear understanding of the basic material properties to enable production of detector material with performance comparable to that of CdZnTe. Brimrose utilized prior experience in the growth and processing of II-VI crystals and produced high purity material and good quality single crystals of CdMgTe. Processing techniques for these crystals including annealing, mechanical and chemical polishing, surface passivation and electrode fabrication were developed. Techniques to characterize pertinent electronic characteristics were developed and gamma ray detectors were fabricated. Feasibility of the development of comprehensive defect modeling in this new class of material was demonstrated by our partner research institute SRI International, to compliment the experimental work. We successfully produced a CdMgTe detector that showed 662 keV gamma response with energy resolution of 3.4% (FWHM) at room temperature, without any additional signal correction. These results are comparable to existing CdZnTe (CZT) technology using the same detector size and testing conditions. We have successfully demonstrated detection of gamma-radiation from various isotopes/sources, using CdMgTe thus clearly proving the feasibility that CdMgTe is an excellent, low-cost alternative to CdZnTe.

  18. Radiation hard cryogenic silicon detectors

    International Nuclear Information System (INIS)

    Casagrande, L.; Abreu, M.C.; Bell, W.H.; Berglund, P.; Boer, W. de; Borchi, E.; Borer, K.; Bruzzi, M.; Buontempo, S.; Chapuy, S.; Cindro, V.; Collins, P.; D'Ambrosio, N.; Da Via, C.; Devine, S.; Dezillie, B.; Dimcovski, Z.; Eremin, V.; Esposito, A.; Granata, V.; Grigoriev, E.; Hauler, F.; Heijne, E.; Heising, S.; Janos, S.; Jungermann, L.; Konorov, I.; Li, Z.; Lourenco, C.; Mikuz, M.; Niinikoski, T.O.; O'Shea, V.; Pagano, S.; Palmieuri, V.G.; Paul, S.; Pirollo, S.; Pretzl, K.; Rato, P.; Ruggiero, G.; Smith, K.; Sonderegger, P.; Sousa, P.; Verbitskaya, E.; Watts, S.; Zavrtanik, M.

    2002-01-01

    It has been recently observed that heavily irradiated silicon detectors, no longer functional at room temperature, 'resuscitate' when operated at temperatures below 130 K. This is often referred to as the 'Lazarus effect'. The results presented here show that cryogenic operation represents a new and reliable solution to the problem of radiation tolerance of silicon detectors

  19. Synchrotron radiation and multichannel detectors in structural analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mokulskii, M

    1979-10-01

    A survey is presented of the development of multichannel synchrotron X radiation detectors for the structural analysis of crystals. Tests are currently under way of a 4-thousand-channel plane detector of soft X radiation. The detector consists of a multiwire proportional counter using argon and CO/sub 2/ as the working gases. The detector is coupled to a computer processing information and displaying the respective X-ray diffraction images on the monitor. The described equipment allows imaging, eg., the cross section of the elementary cell of a DNA crystal. A 16-thousand-channel detector exists in the present time and the building is envisaged of a detector with 65 thousand channels.

  20. Synchrotron radiation and multichannel detectors in structural analysis

    International Nuclear Information System (INIS)

    Mokulskij, M.

    1979-01-01

    A survey is presented of the development of multichannel synchrotron X radiation detectors for the structural analysis of crystals. Tests are currently under way of a 4-thousand-channel plane detector of soft X radiation. The detector consists of a multiwire proportional counter using argon and CO 2 as the working gases. The detector is coupled to a computer processing information and displaying the respective X-ray diffraction images on the monitor. The described equipment allows imaging, eg., the cross section of the elementary cell of a DNA crystal. A 16-thousand-channel detector exists in the present time and the building is envisaged of a detector with 65 thousand channels. (J.B.)

  1. Detectors for particle radiation. 2. rev. ed.

    International Nuclear Information System (INIS)

    Kleinknecht, K.

    1987-01-01

    This book is a description of the set-up and mode of action of detectors for charged particles and gamma radiation for students of physics, as well as for experimental physicists and engineers in research and industry: Ionization chamber, proportional counter, semiconductor counter; proportional chamber, drift chamber, bubble chamber, spark chamber, photomultiplier, laser ionization, silicion strip detector; Cherenkov counter, transition radiation detector; electron-photon-cascade counter, hadron calorimeter; magnetic spectrometer; applications in nuclear medicine, geophysics, space travel, atom physics, nuclear physics, and high-energy physics. With 149 figs., 20 tabs [de

  2. Applications of noble gas radiation detectors to counter-terrorism

    International Nuclear Information System (INIS)

    Vanier, Peter E.; Forman, Leon

    2002-01-01

    Radiation detectors are essential tools in the detection, analysis and disposition of potential terrorist devices containing hazardous radioactive and/or fissionable materials. For applications where stand-off distance and source shielding are limiting factors, large detectors have advantages over small ones. The ability to distinguish between Special Nuclear Materials and false-positive signals from natural or man-made benign sources is also important. Ionization chambers containing compressed noble gases, notably xenon and helium-3, can be scaled up to very large sizes, improving the solid angle for acceptance of radiation from a distant source. Gamma spectrometers using Xe have a factor of three better energy resolution than NaI scintillators, allowing better discrimination between radioisotopes. Xenon detectors can be constructed so as to have extremely low leakage currents, enabling them to operate for long periods of time on batteries or solar cells. They are not sensitive to fluctuations in ambient temperature, and are therefore suitable for deployment in outdoor locations. Position-sensitive 3He chambers have been built as large as 3000 cm2, and with spatial resolution of less than 1 mm. Combined with coded apertures made of cadmium, they can be used to create images of thermal neutron sources. The natural background of spallation neutrons from cosmic rays generates a very low count rate, so this instrument could be quite effective at identifying a man-made source, such as a spontaneous fission source (Pu) in contact with a moderator (high explosive)

  3. Method of neutralising the effects of electromagnetic radiation in a radiation detector and a radiation detector applying the procedure

    International Nuclear Information System (INIS)

    Gripentog, W.G.

    1972-01-01

    Circuitry is described by means of which radiation detectors of the Neher-White type, employing ionisation chambers can be unaffected by electromagnetic radiation which would otherwise cause inductive effects leading to erroneous signals. It is therefore unnecessary to use shielded cables for these instruments. (JIW)

  4. Development of RISA (radiation induced surface activation) detectors for onsite sensing and microdosimetry

    International Nuclear Information System (INIS)

    Date, H.; Shimozuma, M.; Tomozawa, H.; Takamasa, T.; Okamoto, K.

    2003-01-01

    We investigate a new technique for radiation detection using radiation induced surface activation (RISA) phenomenon which is found in oxide materials (with high resistivity) causing current conduction through the irradiation of gamma or beta rays. The RISA current has been observed typically in Rutile-type TiO 2 . We have performed a Monte Carlo simulation of gamma ray photons in TiO 2 and backing layers to make clear carrier generation processes leading to the conduction and to develop new type detectors for onsite sensing and microdosimetry. Results show that the dominant process to generate electron-hole pairs in thin TiO 2 layer is collisional interaction of electrons generated in backing layer, which suggest the RISA detector can be used for estimating the absorbed dose in bio-materials. (author)

  5. The HERMES dual-radiator RICH detector

    CERN Document Server

    Jackson, H E

    2003-01-01

    The HERMES experiment emphasizes measurements of semi-inclusive deep-inelastic scattering. Most of the hadrons produced lie between 2 and 10 GeV, a region in which it had not previously been feasible to separate pions, kaons, and protons with standard particle identification (PID) techniques. The recent development of new clear, large, homogeneous and hydrophobic silica aerogel material with a low index of refraction offered the means to apply RICH PID techniques to this difficult momentum region. The HERMES instrument uses two radiators, C sub 4 F sub 1 sub 0 , a heavy fluorocarbon gas, and a wall of silica aerogel tiles. A lightweight spherical mirror constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality provides optical focusing on a photon detector consisting of 1934 photomultiplier tubes (PMT) for each detector half. The PMT array is held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet. Ring recon...

  6. Long-distance transmission of light in a scintillator-based radiation detector

    Science.gov (United States)

    Dowell, Jonathan L.; Talbott, Dale V.; Hehlen, Markus P.

    2017-07-11

    Scintillator-based radiation detectors capable of transmitting light indicating the presence of radiation for long distances are disclosed herein. A radiation detector can include a scintillator layer and a light-guide layer. The scintillator layer is configured to produce light upon receiving incident radiation. The light-guide layer is configured to receive light produced by the scintillator layer and either propagate the received light through the radiation detector or absorb the received light and emit light, through fluorescence, that is propagated through the radiation detector. A radiation detector can also include an outer layer partially surrounding the scintillator layer and light-guide layer. The index of refraction of the light-guide layer can be greater than the index of refraction of adjacent layers.

  7. Electron Beam Induced Radiation Damage of the Semiconductor Radiation Detector based on Silicon

    International Nuclear Information System (INIS)

    Kim, Han Soo; Kim, Yong Kyun; Park, Se Hwan; Haa, Jang Ho; Kang, Sang Mook; Chung, Chong Eun; Cho, Seung Yeon; Park, Ji Hyun; Yoon, Tae Hyung

    2005-01-01

    A Silicon Surface Barrier (SSB) semiconductor detector which is generally used to detect a charged particle such as an alpha particle was developed. The performance of the developed SSB semiconductor detector was measured with an I-V curve and an alpha spectrum. The response for an alpha particle was measured by Pu-238 sources. A SSB semiconductor detector was irradiated firstly at 30sec, at 30μA and secondly 40sec, 40μA with a 2MeV pulsed electron beam generator in KAERI. And the electron beam induced radiation damage of a homemade SSB detector and the commercially available PIN photodiode were investigated. An annealing effect of the damaged SSB and PIN diode detector were also investigated using a Rapid Thermal Annealing (RTA). This data may assist in designing the silicon based semiconductor radiation detector when it is operated in a high radiation field such as space or a nuclear power plant

  8. Radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ohata, Shuichi; Takeuchi, Yoji

    1968-10-30

    Herein disclosed is an ionization chamber the airtightness of which can be readily tested. The ionization chamber is characterized in that a small amount of helium gas is filled in the chamber in combination with other ionization gases such as argon gas, xenon gas and the like. Helium leakage from the chamber is measured by a known helium gas sensor in a vacuum vessel. Hence the long term drift of the radiation detector sensitivity may be determined.

  9. An integrated circuit/microsystem/nano-enhanced four species radiation sensor for inexpensive fissionable material detection

    Science.gov (United States)

    Waguespack, Randy Paul

    2011-12-01

    Small scale radiation detectors sensitive to alpha, beta, electromagnetic, neutron radiation are needed to combat the threat of nuclear terrorism and maintain national security. There are many types of radiation detectors on the market, and the type of detector chosen is usually determined by the type of particle to be detected. In the case of fissionable material, an ideal detector needs to detect all four types of radiation, which is not the focus of many detectors. For fissionable materials, the two main types of radiation that must be detected are gamma rays and neutrons. Our detector uses a glass or quartz scintillator doped with 10B nanoparticles to detect all four types of radiation particles. Boron-10 has a thermal neutron cross section of 3,840 barns. The interaction between the neutron and boron results in a secondary charge particle in the form of an alpha particle to be emitted, which is detectable by the scintillator. Radiation impinging on the scintillator matrix produces varying optical pulses dependent on the energy of the particles. The optical pulses are then detected by a photomultiplier (PM) tube, creating a current proportional to the energy of the particle. Current pulses from the PM tube are differentiated by on-chip pulse height spectroscopy, allowing for source discrimination. The pulse height circuitry has been fabricated with discrete circuits and designed into an integrated circuit package. The ability to replace traditional PM tubes with a smaller, less expensive photomultiplier will further reduce the size of the device and enhance the cost effectiveness and portability of the detector.

  10. Stable room-temperature thallium bromide semiconductor radiation detectors

    Science.gov (United States)

    Datta, A.; Fiala, J.; Becla, P.; Motakef, Shariar

    2017-10-01

    Thallium bromide (TlBr) is a highly efficient ionic semiconductor with excellent radiation detection properties. However, at room temperature, TlBr devices polarize under an applied electric field. This phenomenon not only degrades the charge collection efficiency of the detectors but also promotes chemical reaction of the metal electrodes with bromine, resulting in an unstable electric field and premature failure of the device. This drawback has been crippling the TlBr semiconductor radiation detector technology over the past few decades. In this exhaustive study, this polarization phenomenon has been counteracted using innovative bias polarity switching schemes. Here the highly mobile Br- species, with an estimated electro-diffusion velocity of 10-8 cm/s, face opposing electro-migration forces during every polarity switch. This minimizes the device polarization and availability of Br- ions near the metal electrode. Our results indicate that it is possible to achieve longer device lifetimes spanning more than 17 000 h (five years of 8 × 7 operation) for planar and pixelated radiation detectors using this technique. On the other hand, at constant bias, 2500 h is the longest reported lifetime with most devices less than 1000 h. After testing several biasing switching schemes, it is concluded that the critical bias switching frequency at an applied bias of 1000 V/cm is about 17 μHz. Using this groundbreaking result, it will now be possible to deploy this highly efficient room temperature semiconductor material for field applications in homeland security, medical imaging, and physics research.

  11. Stable room-temperature thallium bromide semiconductor radiation detectors

    Directory of Open Access Journals (Sweden)

    A. Datta

    2017-10-01

    Full Text Available Thallium bromide (TlBr is a highly efficient ionic semiconductor with excellent radiation detection properties. However, at room temperature, TlBr devices polarize under an applied electric field. This phenomenon not only degrades the charge collection efficiency of the detectors but also promotes chemical reaction of the metal electrodes with bromine, resulting in an unstable electric field and premature failure of the device. This drawback has been crippling the TlBr semiconductor radiation detector technology over the past few decades. In this exhaustive study, this polarization phenomenon has been counteracted using innovative bias polarity switching schemes. Here the highly mobile Br− species, with an estimated electro-diffusion velocity of 10−8 cm/s, face opposing electro-migration forces during every polarity switch. This minimizes the device polarization and availability of Br− ions near the metal electrode. Our results indicate that it is possible to achieve longer device lifetimes spanning more than 17 000 h (five years of 8 × 7 operation for planar and pixelated radiation detectors using this technique. On the other hand, at constant bias, 2500 h is the longest reported lifetime with most devices less than 1000 h. After testing several biasing switching schemes, it is concluded that the critical bias switching frequency at an applied bias of 1000 V/cm is about 17 μHz. Using this groundbreaking result, it will now be possible to deploy this highly efficient room temperature semiconductor material for field applications in homeland security, medical imaging, and physics research.

  12. Detector materials: germanium and silicon

    International Nuclear Information System (INIS)

    Haller, E.E.

    1981-11-01

    This article is a summary of a short course lecture given in conjunction with the 1981 Nuclear Science Symposium. The basic physical properties of elemental semiconductors are reviewed. The interaction of energetic radiation with matter is discussed in order to develop a feeling for the appropriate semiconductor detector dimensions. The extremely low net dopant concentrations which are required are derived directly from the detector dimensions. A survey of the more recent techniques which have been developed for the analysis of detector grade semiconductor single crystals is presented

  13. Monolithic active pixel radiation detector with shielding techniques

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W.

    2018-03-20

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  14. Radiation damage studies for the D0 silicon detector

    International Nuclear Information System (INIS)

    Lehner, F.

    2004-01-01

    We report on irradiation studies performed on spare production silicon detector modules for the current D0 silicon detector. The lifetime expectations due to radiation damage effects of the existing silicon detector are reviewed. A new upgrade project was started with the goal of a complete replacement of the existing silicon detector. In that context, several investigations on the radiation hardness of new prototype silicon microstrip detectors were carried out. The irradiation on different detector types was performed with 10 MeV protons up to fluences of 10 14 p/cm 2 at the J.R. Mcdonald Laboratory at Kansas State University. The flux calibration was carefully checked using different normalization techniques. As a result, we observe roughly 40-50% less radiation damage in silicon for 10 MeV p exposure than it is expected by the predicted NIEL scaling

  15. Temperature Dependency and Alpha Response of Semi-Insulating GaAs Schottky Radiation Detector at Low Bias Voltage

    International Nuclear Information System (INIS)

    Kang, Sang Mook; Ha, Jang Ho; Park, Se Hwan; Kim, Han Soo; Kim, Yong Kyun

    2009-01-01

    The last decade has seen a growing interest in semiconductor radiation detectors operated at room or nearly room temperature. Great efforts have been invested in the development of radiation detectors based on semi-insulating (SI) GaAs. The main reasons are as follows: (i) high resistance against radiation damage; (ii) it possesses a good energy resolution, which relates to its active volume; (iii) such a detector also exhibits fast signal rise times, which results from a high mobility and drift velocity of charge carriers; (iv) its large band gap energy allows a SI GaAs detector to operate at room temperature. Other important features are a good technology base and low production and operating costs. An alpha particle monitoring method for the detection of Pu-238 and U-235 is becoming important in homeland security. Alpha measurement in a vacuum is known to provide a good resolution sufficient to separate an isotope abundance in nuclear materials. However, in order to apply it to a high radiation field like a spent fuel treatment facility, a nuclear material loading and unloading process in a vacuum is one of the great disadvantages. Therefore, the main technical issue is to develop a detector for alpha detection at air condition and low power operation for integration type device. In this study we fabricated GaAs Schottky detector by using semi-insulating (SI) wafer and measured current-voltage characteristic curve and alpha response with 5.5 MeV Am-241 source

  16. Calculating the Responses of Self-Powered Radiation Detectors.

    Science.gov (United States)

    Thornton, D. A.

    Available from UMI in association with The British Library. The aim of this research is to review and develop the theoretical understanding of the responses of Self -Powered Radiation Detectors (SPDs) in Pressurized Water Reactors (PWRs). Two very different models are considered. A simple analytic model of the responses of SPDs to neutrons and gamma radiation is presented. It is a development of the work of several previous authors and has been incorporated into a computer program (called GENSPD), the predictions of which have been compared with experimental and theoretical results reported in the literature. Generally, the comparisons show reasonable consistency; where there is poor agreement explanations have been sought and presented. Two major limitations of analytic models have been identified; neglect of current generation in insulators and over-simplified electron transport treatments. Both of these are developed in the current work. A second model based on the Explicit Representation of Radiation Sources and Transport (ERRST) is presented and evaluated for several SPDs in a PWR at beginning of life. The model incorporates simulation of the production and subsequent transport of neutrons, gamma rays and electrons, both internal and external to the detector. Neutron fluxes and fuel power ratings have been evaluated with core physics calculations. Neutron interaction rates in assembly and detector materials have been evaluated in lattice calculations employing deterministic transport and diffusion methods. The transport of the reactor gamma radiation has been calculated with Monte Carlo, adjusted diffusion and point-kernel methods. The electron flux associated with the reactor gamma field as well as the internal charge deposition effects of the transport of photons and electrons have been calculated with coupled Monte Carlo calculations of photon and electron transport. The predicted response of a SPD is evaluated as the sum of contributions from individual

  17. Radiation damage measurements in room temperature semiconductor radiation detectors

    International Nuclear Information System (INIS)

    Franks, L.A.; Olsen, R.W.; James, R.B.; Brunett, B.A.; Walsh, D.S.; Doyle, B.L.; Vizkelethy, G.; Trombka, J.I.

    1998-01-01

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI 2 ) is reviewed and in the case of CZT supplemented by new alpha particle data. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 10 10 p/cm 2 and significant bulk leakage after 10 12 p/cm 2 . CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5 x 10 9 p/cm 2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from moderated fission spectrum of neutrons after fluences up to 10 10 n/cm 2 , although activation was evident. Exposures of CZT to 5 MeV alpha particle at fluences up to 1.5 x 10 10 α/cm 2 produced a near linear decrease in peak position with fluence and increases in FWHM beginning at about 7.5 x 10 9 α/cm 2 . CT detectors show resolution losses after fluences of 3 x 10 9 p/cm 2 at 33 MeV for chlorine-doped detectors. Indium doped material may be more resistant. Neutron exposures (8 MeV) caused resolution losses after fluences of 2 x 10 10 n/cm 2 . Mercuric iodide has been studied with intermediate energy protons (10 to 33 MeV) at fluences up to 10 12 p/cm 2 and with 1.5 GeV protons at fluences up to 1.2 x 10 8 p/cm 2 . Neutron exposures at 8 MeV have been reported at fluences up to 10 15 n/cm 2 . No radiation damage was reported under these irradiation conditions

  18. Successful beam tests for ALICE Transition Radiation Detector

    CERN Multimedia

    2002-01-01

    Another round of beam tests of prototypes for the Transition Radiation Detector (TRD) for ALICE has been completed and there are already some good results. Mass production of the components of the detector will start early next year.   Top view of the setup for the Transition Radiation Detector prototype tests at CERN.On the left, can be seen the full-scale TRD prototype together with four smaller versions. These are busy days for the TRD (Transition Radiation Detector) team of ALICE. Twenty people - mainly from Germany, but also from Russia and Japan - were working hard during the beam tests this autumn at CERN to assess the performance of their detector prototypes. Analysis of the data shows that the TRD can achieve the desired physics goal even for the highest conceivable multiplicities in lead-lead collisions at the LHC. In its final configuration in the ALICE experiment, the TRD will greatly help in identifying high-momentum electrons, which are 'needles in a haystack' that consists mostly of...

  19. Hydrogenated amorphous silicon radiation detectors: Material parameters; radiation hardness; charge collection

    International Nuclear Information System (INIS)

    Qureshi, S.

    1991-01-01

    Properties of hydrogenated amorphous silicon p-i-n diodes relevant to radiation detection applications were studied. The interest in using this material for radiation detection applications in physics and medicine was motivated by its high radiation hardness and the fact that it can be deposited over large area at relatively low cost. Thick, fully depleted a-Si:H diodes are required for sufficient energy deposition by a charged particle and better signal to noise ratio. A sizeable electric field is essential for charge collection in a -Si:H diodes. The large density of ionized defects that exist in the i layer when the diode is under DC bias causes the electric field to be uniform. Material parameters, namely carrier mobility and lifetime and the ionized defect density in thick a-Si:H p-i-n diodes were studied by the transient photoconductivity method. The increase in diode leakage current with reverse bias over the operating bias was consistent with the Poole-Frenkel effect, involving excitation of carriers from neutral defects. The diode noise over the operating voltage range was completely explained in terms of the shot noise component for CR-(RC) 4 (pseudo-Gaussian) shaping at 3 μs shaping time and the noise component at 0 V bias (delta and thermal noise) added in quadrature. Irradiation with 1 Mev neutrons produced no significant degradation in leakage current and noise at fluences exceeding 4 x 10 14 cm -2 . Irradiation with 1.4 Mev proton fluence of 1 x 10 14 cm -2 decreased carrier lifetime by a factor of ∼4. Degradation in leakage current and noise became significant at proton fluence of ∼10 13 cm -2

  20. Experiences with radiation portal detectors for international rail transport

    International Nuclear Information System (INIS)

    Stromswold, David C.; McCormick, Kathleen R.; Todd, Lindsay C.; Ashbaker, Eric D.; Evans, J.C.

    2006-01-01

    Radiation detectors monitored trains at two international borders to evaluate the performance of NaI(Tl) and plastic (polyvinyltoluene: PVT) gamma-ray detectors to characterize rail cargo. The detectors included a prototype NaI(Tl) radiation-portal-monitor panel having four large detectors (10-cm x 10-cm x 41-cm) and a PVT panel with a 41 cm x 173 cm x 3.8-cm detector. Spectral data from the NaI(Tl) and PVT detectors were recorded. Of particular emphasis was the identification of naturally occurring radioactive material (NORM) and the resultant frequency of nuisance alarms. For rail monitoring, the difficulty in stopping trains to perform secondary inspection on alarming cars creates a need for reliable identification of NORM during initial screening. Approximately 30 trains were monitored, and the commodities in individual railcars were ascertained from manifest information. At one test site the trains carried inter-modal containers that had been unloaded from ships, and at the other site the trains contained bulk cargo or individual items in boxcars or flatbeds. NORM encountered included potash, liquefied petroleum gas, fireworks, televisions, and clay-based products (e.g., pottery). Analysis of the spectral data included the use of the template-fitting program GADRAS/FitToDB from Sandia National Laboratories. For much of the NORM the NaI(Tl) data produced a correct identification of the radionuclides present in the railcars. The same analysis was also used for PVT data in which the spectral information (no peaks but only gradual spectral changes including Compton edges) was limited. However, the PVT analysis provided correct identification of 40K and 226Ra in many cases

  1. Transition-radiation detectors for cosmic-ray research

    International Nuclear Information System (INIS)

    Mueller, D.; Chicago Univ., Ill.

    1975-01-01

    Transition-radiation detectors for cosmic-ray work are described which consist of plastic foam of multiple plastic foil radiators, followed by proportional chambers. A summary of the properties of such detectors is given, and the detection and discrimination efficiencies for energetic particles are discussed. Several possible applications of such devices for studies of cosmic-ray particles in the energy region γ=E/mc 2 >10 3 are advertised

  2. PAMELA Space Mission: The Transition Radiation Detector

    Science.gov (United States)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; De Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2003-07-01

    PAMELA telescope is a satellite-b orne magnetic spectrometer built to fulfill the primary scientific objectives of detecting antiparticles (antiprotons and positrons) in the cosmic rays, and to measure spectra of particles in cosmic rays. The PAMELA telescope is currently under integration and is composed of: a silicon tracker housed in a permanent magnet, a time of flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD detector is composed of 9 sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD detector characteristics will be described along with its performance studied exposing the detector to particle beams of electrons, pions, muons and protons of different momenta at both CERN-PS and CERN-SPS facilities.

  3. X-Ray and Gamma-Ray Radiation Detector

    DEFF Research Database (Denmark)

    2015-01-01

    Disclosed is a semiconductor radiation detector for detecting X-ray and / or gamma-ray radiation. The detector comprises a converter element for converting incident X-ray and gamma-ray photons into electron-hole pairs, at least one cathode, a plurality of detector electrodes arranged with a pitch...... (P) along a first axis, a plurality of drift electrodes, a readout circuitry being configured to read out signals from the plurality of detector electrodes and a processing unit connected to the readout circuitry and being configured to detect an event in the converter element. The readout circuitry...... is further configured to read out signals from the plurality of drift electrodes, and the processing unit is further configured to estimate a location of the event along the first axis by processing signals obtained from both the detector electrodes and the drift electrodes, the location of the event along...

  4. Measurement of radiation shielding properties of polymer composites by using HPGe detector

    International Nuclear Information System (INIS)

    Gupta, Anil; Pillay, H.C.M.; Kale, P.K.; Datta, D.; Suman, S.K.; Gover, V.

    2014-01-01

    Lead is the most common radiation shield and its composite with polymers can be used as flexible radiation shields for different applications. However, lead is very hazardous and has been found to be associated with neurological disorders, kidney failure and hematotoxicity. Lead free radiation shield material has been developed by synthesizing radiation cross linked PDMS/Bi 2 O 3 polymer composites. In order to have a lead free radiation shield the relevant shielding properties such as linear attenuation, half value thickness (HVT) and tenth value thickness (TVT) have been measured by using HPGe detector. The present study describes the methodology of measurement of the shielding properties of the lead free shield material. In the measurement gamma energies such as 59.537 keV ( 241 Am), 122.061 keV and 136.474 keV ( 57 Co) are taken into consideration

  5. Radiation field mapping using a mechanical-electronic detector

    Energy Technology Data Exchange (ETDEWEB)

    Czayka, M., E-mail: mczayka@kent.ed [College of Technology, Kent State University-Ashtabula 3300 Lake Road West, Ashtabula, OH 44004 (United States); Program on Electron Beam Technology, Kent State University, P.O. Box 1028, Middlefield, OH 44062 (United States); Fisch, M. [Program on Electron Beam Technology, Kent State University, P.O. Box 1028, Middlefield, OH 44062 (United States); College of Technology, Kent State University, P.O. Box 5190, Kent, OH 44242-0001 (United States)

    2010-04-15

    A method of radiation field mapping of a scanned electron beam using a Faraday-type detector and an electromechanical linear translator is presented. Utilizing this arrangement, fluence and fluence rate measurements can be made at different locations within the radiation field. The Faraday-type detector used in these experiments differs from most as it consists of a hollow stainless steel sphere. Results are presented in two- and three-dimensional views of the radiation field.

  6. Simple classical model for Fano statistics in radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, David V. [Pacific Northwest National Laboratory, National Security Division - Radiological and Chemical Sciences Group PO Box 999, Richland, WA 99352 (United States)], E-mail: David.Jordan@pnl.gov; Renholds, Andrea S.; Jaffe, John E.; Anderson, Kevin K.; Rene Corrales, L.; Peurrung, Anthony J. [Pacific Northwest National Laboratory, National Security Division - Radiological and Chemical Sciences Group PO Box 999, Richland, WA 99352 (United States)

    2008-02-01

    A simple classical model that captures the essential statistics of energy partitioning processes involved in the creation of information carriers (ICs) in radiation detectors is presented. The model pictures IC formation from a fixed amount of deposited energy in terms of the statistically analogous process of successively sampling water from a large, finite-volume container ('bathtub') with a small dipping implement ('shot or whiskey glass'). The model exhibits sub-Poisson variance in the distribution of the number of ICs generated (the 'Fano effect'). Elementary statistical analysis of the model clarifies the role of energy conservation in producing the Fano effect and yields Fano's prescription for computing the relative variance of the IC number distribution in terms of the mean and variance of the underlying, single-IC energy distribution. The partitioning model is applied to the development of the impact ionization cascade in semiconductor radiation detectors. It is shown that, in tandem with simple assumptions regarding the distribution of energies required to create an (electron, hole) pair, the model yields an energy-independent Fano factor of 0.083, in accord with the lower end of the range of literature values reported for silicon and high-purity germanium. The utility of this simple picture as a diagnostic tool for guiding or constraining more detailed, 'microscopic' physical models of detector material response to ionizing radiation is discussed.

  7. Custom synthesized diamond crystals as state of the art radiation detectors

    International Nuclear Information System (INIS)

    Keddy, R.J.; Nam, T.L.; Fallon, P.J.

    1990-01-01

    The fact that as a radiation detector, diamond is a stable, non-toxic and tissue equivalent (Z=6) material, makes it an ideal candidate for in vivo radiation dosimetry or the dosimetry of general radiation fields in environmental monitoring. Natural diamond crystals have the disadvantage, however, that no two crystals can be guaranteed to have the same response characteristics. This disadvantage can be overcome by synthesizing the crystals under controlled conditions and by using very selective chemistry. Such synthetic diamonds can be used as thermoluminescence dosimeters (TLDs) where they exhibit characteristics comparable to presently available commercial TLDs or they can be used as ionization chambers to produce either ionization currents or pulses where the small physical size of the diamond (1 mm 3 ) and possibilities of digital circuitry makes miniaturization an extremely attractive possibility. It has also been found that they can perform as scintillation detectors. This contribution describes aspects of the performance characteristics of such diamonds in all three modes. 24 refs., 14 figs

  8. Radiation Effects of n-type, Low Resistivity, Spiral Silicon Drift Detector Hybrid Systems

    International Nuclear Information System (INIS)

    Chen, W.; De Geronimo, G.; Carini, G.A.; Gaskin, J.A.; Keister, J.W.; Li, S.; Li, Z.; Ramsey, B.D.; Siddons, D.P.; Smith, G.C.; Verbitskaya, E.

    2011-01-01

    We have developed a new thin-window, n-type, low-resistivity, spiral silicon drift detector (SDD) array - to be used as an extraterrestrial X-ray spectrometer (in varying environments) for NASA. To achieve low-energy response, a thin SDD entrance window was produced using a previously developed method. These thin-window devices were also produced on lower resistivity, thinner, n-type, silicon material, effectively ensuring their radiation hardness in anticipation of operation in potentially harsh radiation environments (such as found around the Jupiter system). Using the Indiana University Cyclotron Facility beam line RERS1, we irradiated a set of suitable diodes up to 5 Mrad and the latest iteration of our ASICs up to 12 Mrad. Then we irradiated two hybrid detectors consisting of newly, such-produced in-house (BNL) SDD chips bonded with ASICs with doses of 0.25 Mrad and 1 Mrad. Also we irradiated another hybrid detector consisting of previously produced (by KETEK) on n-type, high-resistivity SDD chip bonded with BNL's ASICs with a dose of 1 Mrad. The measurement results of radiated diodes (up to 5 Mrad), ASICs (up to 12 Mrad) and hybrid detectors (up to 1 Mrad) are presented here.

  9. Multi-sensor radiation detector system

    International Nuclear Information System (INIS)

    Foster, R.G.; Cyboron, R.D.

    1975-01-01

    The invention is a multi-sensor radiation detection system including a self-powered detector and an ion or fission chamber, preferably joined as a unitary structure, for removable insertion into a nuclear reactor. The detector and chamber are connected electrically in parallel, requiring but two conductors extending out of the reactor to external electrical circuitry which includes a load impedance, a voltage source, and switch means. The switch means are employed to alternately connect the detector and chamber either with th load impedance or with the load impedance and the voltage source. In the former orientation, current through the load impedance indicates flux intensity at the self-powered detector and in the latter orientation, the current indicates flux intensity at the detector and fission chamber, though almost all of the current is contributed by the fission chamber. (auth)

  10. Entropy as a measure of the performance of phosphor materials used in medical imaging radiation detectors

    International Nuclear Information System (INIS)

    Cavouras, D.; Kandarakis, I.; Maris, T.; Panayiotakis, G.S.; Nomicos, C.D.

    2001-01-01

    In information theory, entropy expresses the information gain obtained after detection of a signal concerning the state of a parameter of interest. In this study, entropy has been expressed in terms of physical quantities (emitted optical fluence and MTF) related to the imaging performance of phosphor materials, which are employed in medical imaging radiation detectors. Four phosphor materials, used in the form of laboratory-prepared fluorescent layers (screens), were compared on the basis of their entropy performance. Measurements were performed using 30- and 80-kVp X-ray beams often employed in X-ray imaging. Results showed that phosphor materials with high density and effective atomic number exhibit high entropy performance, especially at the higher X-ray tube voltage of 80 kVp. Entropy values are also affected by the type of activator, which determines the intrinsic X-ray-to-light conversion efficiency, and the spectrum of emitted light. The proximity of the incident X-ray quanta energy to the energy of the K-shell threshold for photoelectric absorption is an additional important factor which increases entropy. This effect was more apparent in the performance of yttrium-based phosphors at the lower voltage of 30 kVp. (orig.)

  11. The design of intelligentized nuclear radiation monitoring detector

    International Nuclear Information System (INIS)

    Meng Yan; Fang Zongliang; Wen Qilin; Li Lirong; Hu Jiewei; Peng Jing

    2010-01-01

    This paper introduced an intelligentized nuclear radiation monitoring detector. The detector contains GM tubes, high voltage power supply and MCU circuit. The detector connect terminal via reformative serial port to provide power, accept the data and sent the command. (authors)

  12. Studies of the ATLAS Inner Detector material using $\\sqrt{s}=$13 TeV $pp$ collision data

    CERN Document Server

    The ATLAS collaboration

    2015-01-01

    The ATLAS Inner Detector comprises three different technologies: the Pixel detector (Pixel), the silicon strip tracker (SCT), and the transition radiation drift tube tracker (TRT). The material in the ATLAS Inner Detector is studied with several methods, using the $pp$ collision sample collected at $\\sqrt{s}=$13 TeV in 2015. The material within the innermost barrel regions of the ATLAS Inner Detector is studied using reconstructed hadronic interaction and photon conversion vertices from samples of minimum bias events. It was found that the description of the Insertable B-Layer, which is the new, innermost Pixel layer installed in 2014, in the geometry model was missing some material components. After updating the model, data and simulation show good agreement at the barrel region. The Pixel services (cables, cooling pipes, support trays) were modified between the Pixel and SCT detectors in 2014. The material in this region is also studied by investigating the efficiency with which tracks reconstructed only in...

  13. Recent results on the development of radiation-hard diamond detectors

    CERN Document Server

    Conway, J S; Bauer, C; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Dabrowski, W; Da Graca, J; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Jamieson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Plano, R; Polesello, P; Prawer, S; Pretzl, Klaus P; Procario, M; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Russ, J; Schnetzer, S; Sciortino, S; Somalwar, S V; Speziali, V; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R; Thomson, G B; Trawick, M; Trischuk, W; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; White, C; Ziock, H J; Zöller, M

    1999-01-01

    Charged particle detectors made from chemical vapor deposition (CVD) diamond have radiation hardness greatly exceeding that of silicon- based detectors. The CERN-based RD42 Collaboration has developed and tested CVD diamond microstrip and pixel detectors with an eye to their application in the intense radiation environment near the interaction region of hadron colliders. This paper presents recent results from tests of these detectors. (4 refs).

  14. Experiences with radiation portal detectors for international rail transport

    Science.gov (United States)

    Stromswold, D. C.; McCormick, K.; Todd, L.; Ashbaker, E. D.; Evans, J. C.

    2006-08-01

    Radiation detectors monitored trains at two international borders to evaluate the performance of NaI(Tl) and plastic (polyvinyltoluene: PVT) gamma-ray detectors to characterize rail cargo. The detectors included a prototype NaI(Tl) radiation-portal-monitor panel having four large detectors (10-cm × 10-cm × 41-cm) and a PVT panel with a 41 cm × 173 cm × 3.8-cm detector. Spectral data from the NaI(Tl) and PVT detectors were recorded. Of particular emphasis was the identification of naturally occurring radioactive material (NORM) and the resultant frequency of nuisance alarms. For rail monitoring, the difficulty in stopping trains to perform secondary inspection on alarming cars creates a need for reliable identification of NORM during initial screening. Approximately 30 trains were monitored, and the commodities in individual railcars were ascertained from manifest information. At one test site, the trains carried inter-modal containers that had been unloaded from ships, and at the other site, the trains contained bulk cargo in tanker cars and hopper cars or individual items in boxcars or flatbeds. NORM encountered included potash, liquefied petroleum gas, fireworks, televisions, and clay-based products (e.g., pottery). Analysis of the spectral data included the use of the template-fitting portion of the program GADRAS developed at Sandia National Laboratories. For most of the NORM, the NaI(Tl) data produced a correct identification of the radionuclides present in the railcars. The same analysis was also used for PVT data in which the spectral information (no peaks but only gradual spectral changes including Compton edges) was limited. However, the PVT analysis provided correct identification of 40K and 226Ra in many cases.

  15. Measurement of environmental radiation using medical scintillation detector in well counter system

    Energy Technology Data Exchange (ETDEWEB)

    Lyu, Kwang Yeul; Park, Yeon Joon; Kim, Min Jeong; Ham, Eun Hye; Yoon, Ji Yeol; Kim, Hyun in; Min, Jung Hwan; Park, Hoon Hee [Dept. of Radiological Technology, Shingu College, Sungnam (Korea, Republic of)

    2015-12-15

    After the Fukushima nuclear accident in 2011, concerns about radiation by people are increasing rapidly. If people could know how much they will be exposed by radiation, it may help them avoiding it and understand what exactly radiation is. By doing this, we were helping to reduce the anxiety of radiation contamination. In this study, we have researched figures of radioactivity with ‘Captus-3000 thyroid uptake measurement systems’ in well counter detector system. The materials were measured with Briquette, Shiitake, Pollock, Button type battery, Alkaline battery, Topsoil, Asphalt, Gasoline, Milk powder, Pine, Basalt stone, Pencil lead, Wasabi, Coarse salt, Tuna(can) Cigar, Beer, and then we categorized those samples into Land resources, Water resources, Foodstuff and Etc (Beer classified as a water resources has been categorized into Foodstuff). Also, we selected the standard radiation source linear 137Cs to measure the sensitivity of well counter detector. After that, we took cpm(counter per minute) for the well counter detector of thyroid uptake system’s sensitivity. Then we compared the results of each material’s cpm and converted those results to Bq/kg unit. There were a little limitation with the measurement equipment because it has less sensitivity than other professional equipment like ‘High purity germanium radiation detector’. Moreover, We didn’t have many choices to decide the materials. As a result, there are macroscopic differences among the rates of material’s spectrum. Therefore, it had meaningful results that showed how much each material had emitted radiation. To compare the material’s cpm with BKG, we’ve compounded their spectrums. By doing that, we were able to detect some differences among the spectrums at specific peak section. Lastly, Button type battery, Alkaline Battery, Briquette, Asphalt and Topsoil showed high value. There were classified emitting high radiation Group A and emitted lower radiation Group B. The Group A

  16. Measurement of environmental radiation using medical scintillation detector in well counter system

    International Nuclear Information System (INIS)

    Lyu, Kwang Yeul; Park, Yeon Joon; Kim, Min Jeong; Ham, Eun Hye; Yoon, Ji Yeol; Kim, Hyun in; Min, Jung Hwan; Park, Hoon Hee

    2015-01-01

    After the Fukushima nuclear accident in 2011, concerns about radiation by people are increasing rapidly. If people could know how much they will be exposed by radiation, it may help them avoiding it and understand what exactly radiation is. By doing this, we were helping to reduce the anxiety of radiation contamination. In this study, we have researched figures of radioactivity with ‘Captus-3000 thyroid uptake measurement systems’ in well counter detector system. The materials were measured with Briquette, Shiitake, Pollock, Button type battery, Alkaline battery, Topsoil, Asphalt, Gasoline, Milk powder, Pine, Basalt stone, Pencil lead, Wasabi, Coarse salt, Tuna(can) Cigar, Beer, and then we categorized those samples into Land resources, Water resources, Foodstuff and Etc (Beer classified as a water resources has been categorized into Foodstuff). Also, we selected the standard radiation source linear 137Cs to measure the sensitivity of well counter detector. After that, we took cpm(counter per minute) for the well counter detector of thyroid uptake system’s sensitivity. Then we compared the results of each material’s cpm and converted those results to Bq/kg unit. There were a little limitation with the measurement equipment because it has less sensitivity than other professional equipment like ‘High purity germanium radiation detector’. Moreover, We didn’t have many choices to decide the materials. As a result, there are macroscopic differences among the rates of material’s spectrum. Therefore, it had meaningful results that showed how much each material had emitted radiation. To compare the material’s cpm with BKG, we’ve compounded their spectrums. By doing that, we were able to detect some differences among the spectrums at specific peak section. Lastly, Button type battery, Alkaline Battery, Briquette, Asphalt and Topsoil showed high value. There were classified emitting high radiation Group A and emitted lower radiation Group B. The Group A

  17. Detection of nuclear radiations; Detectores de radiaciones nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Tanarro Sanz, A

    1959-07-01

    A summary of the lectures about the ordinary detectors of nuclear radiations given by the author in the Courses of Introduction to Nuclear Engineering held at the JEN up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied electronics to Nuclear Engineering so it has been intent to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author) 8 refs.

  18. Modeling of radiation damage recovery in particle detectors based on GaN

    Energy Technology Data Exchange (ETDEWEB)

    Gaubas, E., E-mail: eugenijus.gaubas@ff.vu.lt; Ceponis, T.; Pavlov, J.

    2015-12-15

    The pulsed characteristics of the capacitor-type and PIN diode type detectors based on GaN have been simulated using the dynamic and drift–diffusion models. The drift–diffusion current simulations have been implemented by employing the commercial software package Synopsys TCAD Sentaurus. The bipolar drift regime has been analyzed. The possible internal gain in charge collection through carrier multiplication processes determined by impact ionization has been considered in order to compensate carrier lifetime reduction due to radiation defects introduced into GaN material of detector.

  19. 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.

  20. Application of Rossi-type detectors in radiation protection

    International Nuclear Information System (INIS)

    Menzel, H.G.; Hartmann, G.H.; Krauss, O.; Deutsches Krebsforschungszentrum, Heidelberg

    1983-01-01

    Rossi-type detectors can measure the energy dose and the pertinent quality factor simultaneously and independent of the radiation. This is possible because these detectors are able to measure the energy as well as the LET distribution of the measured radiation. The quality factor is then calculated on this basis. The principle of measurement, problems and solutions are discussed. (orig./HP) [de

  1. Development of TiBr semiconductor crystal for applications as radiation detector and photodetector

    International Nuclear Information System (INIS)

    Oliveira, Icimone Braga de

    2006-01-01

    In this work, Tlbr crystals were grown by the Bridgman method from zone melted materials. The influence of the purification efficiency and the crystalline surface quality on the crystal were studied, evaluating its performance as a radiation detector. Due to significant improvement in the purification and crystals growth, good results have been obtained for the developed detectors. The spectrometric performance of the Tlbr detector was evaluated by 241 Am (59 keV), 133 Ba (80 e 355 keV), 57 Co (122 keV), 22 Na (511 keV) and 137 Cs (662 keV) at room temperature. The best energy resolution results were obtained from purer detectors. Energy resolutions of 10 keV (16%), 12 keV (15%), 12 keV (10%), 28 keV (8%), 31 keV (6%) and 36 keV (5%) to 59, 80, 122, 355, 511 and 662 keV energies, respectively, were obtained. A study on the detection response at -20 deg C was also carried out, as well as the detector stability in function of the time. No significant difference was observed in the energy resolution between measurements at both temperatures. It was observed that the detector instability causes degradation of the spectroscopic characteristics during measurements at room temperature and the instability varies for each detector. This behavior was also verified by other authors. The viability to use the developed Tlbr crystal as a photodetector coupled to scintillators crystals was also studied in this work. Due to its quantum efficiency in the region from 350 to 500 nm, Tlbr shows to be a promising material to be used as a photodetector. As a possible application of this work, the development of a surgical probe has been initiated using the developed Tlbr crystal as the radiation detector of the probe. (author)

  2. Radiation detectors for use in major public events: classification, requirements, main features, tests and lessons learned

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Elder Magalhães de, E-mail: elder@ird.gov.br [Instituto de Radioproteção e Dosimetria (DIRAD/IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Div. de Radiometria

    2017-07-01

    Since September 11, 2001, we have entered a new terrorism era. The possibility of the use of lost/stolen radioactive materials increases the probability of a radiological threat. The real goal intended with the use of a Radiological Dispersal Device (RRD or dirty bomb) or a Radiation Exposure Device (RDE) could be psychological in nature. Panic in the venues and surrounding area would cause more deaths than the RDD itself, therefore these attempts could cause chaos, injury, fear and terror, the main target of terrorists. The response of the national authorities with the support and aid of the IAEA served as an increase of the capability of detection and identification of nuclear and radiological materials. But this response could not be limited only to the MPE, because if the country has radioactive or nuclear facilities they also should be considered in terms of theft, sabotage, illegal transfer, unauthorized access, and any other malicious acts. In 2007, Rio de Janeiro, received the first Brazilian Major Public Event in this new era. This was the first Brazilian operation which largely utilized detectors (personal radiations detectors -PRD- radiological identification detectors, -RID or RIID- and spectral radiations scanners, -backpacks-, HPGe detectors, car-borne and air-borne systems) to protect the venues, the athletes, the population and the environment. (author)

  3. Radiation detectors for use in major public events: classification, requirements, main features, tests and lessons learned

    International Nuclear Information System (INIS)

    Souza, Elder Magalhães de

    2017-01-01

    Since September 11, 2001, we have entered a new terrorism era. The possibility of the use of lost/stolen radioactive materials increases the probability of a radiological threat. The real goal intended with the use of a Radiological Dispersal Device (RRD or dirty bomb) or a Radiation Exposure Device (RDE) could be psychological in nature. Panic in the venues and surrounding area would cause more deaths than the RDD itself, therefore these attempts could cause chaos, injury, fear and terror, the main target of terrorists. The response of the national authorities with the support and aid of the IAEA served as an increase of the capability of detection and identification of nuclear and radiological materials. But this response could not be limited only to the MPE, because if the country has radioactive or nuclear facilities they also should be considered in terms of theft, sabotage, illegal transfer, unauthorized access, and any other malicious acts. In 2007, Rio de Janeiro, received the first Brazilian Major Public Event in this new era. This was the first Brazilian operation which largely utilized detectors (personal radiations detectors -PRD- radiological identification detectors, -RID or RIID- and spectral radiations scanners, -backpacks-, HPGe detectors, car-borne and air-borne systems) to protect the venues, the athletes, the population and the environment. (author)

  4. Diamond and silicon pixel detectors in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Jieh-Wen

    2012-10-15

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

  5. Diamond and silicon pixel detectors in high radiation environments

    International Nuclear Information System (INIS)

    Tsung, Jieh-Wen

    2012-10-01

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10 16 particles per cm 2 , which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10 15 particles per cm 2 .

  6. Radiation and detectors introduction to the physics of radiation and detection devices

    CERN Document Server

    Cerrito, Lucio

    2017-01-01

    This textbook provides an introduction to radiation, the principles of interaction between radiation and matter, and the exploitation of those principles in the design of modern radiation detectors. Both radiation and detectors are given equal attention and their interplay is carefully laid out with few assumptions made about the prior knowledge of the student. Part I is dedicated to radiation, broadly interpreted in terms of energy and type, starting with an overview of particles and forces, an extended review of common natural and man-made sources of radiation, and an introduction to particle accelerators. Particular attention is paid to real life examples, which place the types of radiation and their energy in context. Dosimetry is presented from a modern, user-led point of view, and relativistic kinematics is introduced to give the basic knowledge needed to handle the more formal aspects of radiation dynamics and interaction. The explanation of the physics principles of interaction between radiation an...

  7. Four channel Cosmic Ray detector based on polymaq

    Science.gov (United States)

    Herrera-Guzman, K. N.; Gutierrez-Sanchez, R. A.; Felix, J.

    2017-01-01

    The Cherenkov radiation has been widely studied in transparent materials, and applied to detect and identify elementary particles. But it has not been widely studied in opaque materials. A four channels radiation detector has been designed, built, characterized, and operated; based on four polymaq (UHMW-PE) bars of 2.54 cm X 5.08 cm X 25.4 cm, which is an opaque material to visible radiation to the human eye. Silicon photo detectors, Hamamatsu, avalanche type (APD) are used to detect the radiation produced by the passage of particles in the detector blocks. The design, construction, characterization, operation, and preliminary results of this cosmic ray detector details are presented.

  8. Advanced processing of CdTe pixel radiation detectors

    Science.gov (United States)

    Gädda, A.; Winkler, A.; Ott, J.; Härkönen, J.; Karadzhinova-Ferrer, A.; Koponen, P.; Luukka, P.; Tikkanen, J.; Vähänen, S.

    2017-12-01

    We report a fabrication process of pixel detectors made of bulk cadmium telluride (CdTe) crystals. Prior to processing, the quality and defect density in CdTe material was characterized by infrared (IR) spectroscopy. The semiconductor detector and Flip-Chip (FC) interconnection processing was carried out in the clean room premises of Micronova Nanofabrication Centre in Espoo, Finland. The chip scale processes consist of the aluminum oxide (Al2O3) low temperature thermal Atomic Layer Deposition (ALD), titanium tungsten (TiW) metal sputtering depositions and an electroless Nickel growth. CdTe crystals with the size of 10×10×0.5 mm3 were patterned with several photo-lithography techniques. In this study, gold (Au) was chosen as the material for the wettable Under Bump Metalization (UBM) pads. Indium (In) based solder bumps were grown on PSI46dig read out chips (ROC) having 4160 pixels within an area of 1 cm2. CdTe sensor and ROC were hybridized using a low temperature flip-chip (FC) interconnection technique. The In-Au cold weld bonding connections were successfully connecting both elements. After the processing the detector packages were wire bonded into associated read out electronics. The pixel detectors were tested at the premises of Finnish Radiation Safety Authority (STUK). During the measurement campaign, the modules were tested by exposure to a 137Cs source of 1.5 TBq for 8 minutes. We detected at the room temperature a photopeak at 662 keV with about 2 % energy resolution.

  9. Radiation detection and measurement

    International Nuclear Information System (INIS)

    Knoll, G.F.

    1979-01-01

    Introductory material covers radiation sources, radiation interactions, general properties of radiation detectors, and counting statistics and error prediction. This is followed by detailed sections on gas-filled detectors, scintillation counters, semiconductor detectors, neutron detectors and spectroscopy, detector electronics and pulse processing, and miscellaneous radiation detectors and applications

  10. 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.

  11. Cadmium Manganese Telluride (Cd1-xMnxTe): A potential material for room-temperature radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, A.; Cui, Y.; Bolotnikov, A.; Camarda, G.; Yang, G.; Kim, K-H.; Gul, R.; Xu, L.; Li, L.; Mycielski, A.; and James, R.B.

    2010-07-11

    Cadmium Manganese Telluride (CdMnTe) recently emerged as a promising material for room-temperature X- and gamma-ray detectors. It offers several potential advantages over CdZnTe. Among them is its optimal tunable band gap ranging from 1.7-2.2 eV, and its relatively low (< 50%) content of Mn compared to that of Zn in CdZnTe that assures this favorable band-gap range. Another important asset is the segregation coefficient of Mn in CdTe that is approximately unity compared to 1.35 for Zn in CdZnTe, so ensuring the homogenous distribution of Mn throughout the ingot; hence, a large-volume stoichiometric yield is attained. However, some materials issues primarily related to the growth process impede the production of large, defect-free single crystals. The high bond-ionicity of CdMnTe entails a higher propensity to crystallize into a hexagonal structure rather than to adopt the expected zinc-blend structure, which is likely to generate twins in the crystals. In addition, bulk defects generate in the as-grown crystals due to the dearth of high-purity Mn, which yields a low-resistivity material. In this presentation, we report on our observations of such material defects in current CdMnTe materials, and our evaluation of its potential as an alternative detector material to the well-known CdZnTe detectors. We characterized the bulk defects of several indium- and vanadium-doped Cd1-xMnxTe crystals by using several advanced techniques, viz., micro-scale mapping, white-beam x-ray diffraction/reflection topography, and chemical etching. Thereafter, we fabricated some detectors from selected CdMnTe crystals, characterized their electrical properties, and tested their performance as room-temperature X- and gamma-ray detectors. Our experimental results indicate that CdMnTe materials could well prove to become a viable alternative in the near future.

  12. A conductive surface coating for Si-CNT radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, Antonio, E-mail: antonio.valentini@ba.infn.it [Dipartimento di Fisica, Università degli Studi di Bari, Via Orabona 4, 70125 Bari (Italy); Valentini, Marco [INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Ditaranto, Nicoletta [Dipartimento di Chimica, Università degli Studi di Bari, Via Amendola 173, 70126 Bari (Italy); Melisi, Domenico [INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Aramo, Carla, E-mail: aramo@na.infn.it [INFN, Sezione di Napoli, Via Cintia 2, 80126 Napoli (Italy); Ambrosio, Antonio [CNR-SPIN U.O.S. di Napoli and Dipartimento di Scienze Fisiche, Università degli Studi di Napoli “Federico II”, Via Cintia 2, 80126 Napoli (Italy); Casamassima, Giuseppe [Dipartimento di Fisica, Università degli Studi di Bari, Via Orabona 4, 70125 Bari (Italy); INFN, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Cilmo, Marco [INFN, Sezione di Napoli, and Dipartimento di Scienze Fisiche, Università degli Studi di Napoli “Federico II”, Via Cintia 2, 80126 Napoli (Italy); Fiandrini, Emanuele [INFN, Sezione di Perugia, and Dipartimento di Fisica, Università degli Studi di Perugia, Piazza Università 1, 06100 Perugia (Italy); Grossi, Valentina [INFN, Sezione di L’Aquila, and Dipartimento di Scienze Fisiche e Chimiche, Università degli Studi dell’Aquila, Via Vetoio 10 Coppito, 67100 L’Aquila (Italy); and others

    2015-08-01

    Silicon–Carbon Nanotube radiation detectors need an electrically conductive coating layer to avoid the nanotube detachment from the silicon substrate and uniformly transmit the electric field to the entire nanotube active surface. Coating material must be transparent to the radiation of interest, and must provide the drain voltage necessary to collect charges generated by incident photons. For this purpose various materials have been tested and proposed in photodetector and photoconverter applications. In this article interface properties and electrical contact behavior of Indium Tin Oxide films on Carbon Nanotubes have been analyzed. Ion Beam Sputtering has been used to grow the transparent conductive layer on the nanotubes. The films were deposited at room temperature with Oxygen/Argon mixture into the sputtering beam, at fixed current and for different beam energies. Optical and electrical analyses have been performed on films. Surface chemical analysis and in depth profiling results obtained by X-ray Photoelectron Spectroscopy of the Indium Tin Oxide layer on nanotubes have been used to obtain the interface composition. Results have been applied in photodetectors realization based on multi wall Carbon Nanotubes on silicon. - Highlights: • ITO was deposited by Ion Beam Sputtering on MWCNT. • ITO on CNT makes an inter-diffusion layer of the order of one hundred nanometers. • Improvements of quantum efficiency of photon detectors based on CNT with ITO.

  13. Use of HgI2 as gamma radiation detector

    International Nuclear Information System (INIS)

    Perez Morales, J.M.

    1993-01-01

    The Mercuric Iodide (HgI 2 ) has become one of the most promising room temperature semiconductors for the construction of X and gamma radiation detectors. The classical methods of spectroscopy have not demonstrated to achieve optimum results with HgI 2 detectors, mainly due to its particular carrier transport properties. Several alternative spectroscopic methods developed in the last ten years are presented and commented, selecting for a complete study one of them: 'The Partial Charge Collection Method'. The transport properties of the carriers generated by the radiation in the detector is specially important for understanding the spectroscopic behaviour of the HgI 2 detectors. For a rigorous characterization of this transport, it has been studied a digital technique for the analysis of the electric pulses produced by the radiation. Theoretically, it has been developed a Monte Carlo simulation of the radiation detection and the electronic signal treatment processes with these detectors in the energy range of 60-1300 KeV. These codes are applied to the study of the The Partial Charge Collection Method and its comparison with gaussian methods. Experimentally, this digital techniques is used for the study of the transport properties of thin HgI 2 detectors. Special interest is given to the contribution of the slower carriers, the holes, obtaining some consequent of spectroscopic interest. Finally, it is presented the results obtained with the first detectors grown and mounted in CIEMAT with own technology. (author). 129 ref

  14. Electromagnetic disturbance neutralizing radiation detector

    International Nuclear Information System (INIS)

    Gripentog, W.G.

    1975-01-01

    A radiation detector of the Neher-White type is described which automatically neutralizes induced negative charges on the electrometer tube control grid which shut off the electrometer tube. The detector includes means for establishing a voltage of one polarity in response to plate current and voltage of opposite polarity in response to an absence of plate current and means for connecting the control grid to a reference potential for draining the negative charge in response to the voltage of opposite polarity. (author)

  15. Solid-state radiation detectors for active personal dosimetry and radiations source tracking

    International Nuclear Information System (INIS)

    Talpalariu, Corneliu; Talpalariu, Jeni; Matei, Corina; Lita, Ioan; Popescu, Oana

    2010-01-01

    We report on the design of the readout electronics using PIN diode radiation detector of 5 mm thickness for nuclear safety and active personal dosimetry. Our effort consisted in designing and fabricating the electronics to reflect the needs of gamma radiations dosimetry and hybrids PIN diode arrays for charged particle detectors. We report results obtained during testing and characterizing the new devices in gamma fields, operating at room temperature. There were determined the energy spectrum resolution, radiation hardness and readout rate. Also, data recording methods and parallel acquisition problems from a transducer matrix are presented. (authors)

  16. Material specific X-ray imaging using an energy-dispersive pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Egan, Christopher K., E-mail: christopher.egan@manchester.ac.uk [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Wilson, Matthew D.; Veale, Matthew C.; Seller, Paul [STFC Rutherford Appleton Laboratory, Harwell, Didcot, Oxfordshire OX11 0QX (United Kingdom); Jacques, Simon D.M.; Cernik, Robert J. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom)

    2014-04-01

    By imaging the X-ray spectral properties or ‘colours’ we have shown how material specific imaging can be performed. Using a pixelated energy-dispersive X-ray detector we record the absorbed and emitted hard X-radiation and measure the energy (colour) and intensity of the photons. Using this technology, we are not only able to obtain attenuation contrast but also to image chemical (elemental) variations inside objects, potentially opening up a very wide range of applications from materials science to medical diagnostics.

  17. Radiative sky cooling: fundamental physics, materials, structures, and applications

    Science.gov (United States)

    Sun, Xingshu; Sun, Yubo; Zhou, Zhiguang; Alam, Muhammad Ashraful; Bermel, Peter

    2017-07-01

    Radiative sky cooling reduces the temperature of a system by promoting heat exchange with the sky; its key advantage is that no input energy is required. We will review the origins of radiative sky cooling from ancient times to the modern day, and illustrate how the fundamental physics of radiative cooling calls for a combination of properties that may not occur in bulk materials. A detailed comparison with recent modeling and experiments on nanophotonic structures will then illustrate the advantages of this recently emerging approach. Potential applications of these radiative cooling materials to a variety of temperature-sensitive optoelectronic devices, such as photovoltaics, thermophotovoltaics, rectennas, and infrared detectors, will then be discussed. This review will conclude by forecasting the prospects for the field as a whole in both terrestrial and space-based systems.

  18. A self-powered thin-film radiation detector using intrinsic high-energy current

    Energy Technology Data Exchange (ETDEWEB)

    Zygmanski, Piotr, E-mail: pzygmanski@LROC.HARVARD.EDU, E-mail: Erno-Sajo@uml.edu [Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States); Sajo, Erno, E-mail: pzygmanski@LROC.HARVARD.EDU, E-mail: Erno-Sajo@uml.edu [Department of Physics and Applied Physics, Medical Physics Program, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States)

    2016-01-15

    Purpose: The authors introduce a radiation detection method that relies on high-energy current (HEC) formed by secondary charged particles in the detector material, which induces conduction current in an external readout circuit. Direct energy conversion of the incident radiation powers the signal formation without the need for external bias voltage or amplification. The detector the authors consider is a thin-film multilayer device, composed of alternating disparate electrically conductive and insulating layers. The optimal design of HEC detectors consists of microscopic or nanoscopic structures. Methods: Theoretical and computational developments are presented to illustrate the salient properties of the HEC detector and to demonstrate its feasibility. In this work, the authors examine single-sandwiched and periodic layers of Cu and Al, and Au and Al, ranging in thickness from 100 nm to 300 μm and separated by similarly sized dielectric gaps, exposed to 120 kVp x-ray beam (half-value thickness of 4.1 mm of Al). The energy deposition characteristics and the high-energy current were determined using radiation transport computations. Results: The authors found that in a dual-layer configuration, the signal is in the measurable range. For a defined total detector thickness in a multilayer structure, the signal sharply increases with decreasing thickness of the high-Z conductive layers. This paper focuses on the computational results while a companion paper reports the experimental findings. Conclusions: Significant advantages of the device are that it does not require external power supply and amplification to create a measurable signal; it can be made in any size and geometry, including very thin (sub-millimeter to submicron) flexible curvilinear forms, and it is inexpensive. Potential applications include medical dosimetry (both in vivo and external), radiation protection, and other settings where one or more of the above qualities are desired.

  19. A novel diamond-based beam position monitoring system for the High Radiation to Materials facility at CERN SPS

    CERN Document Server

    AUTHOR|(CDS)2092886; Höglund, Carina

    The High Radiation to Materials facility employs a high intensity pulsed beam imposing several challenges on the beam position monitors. Diamond has been shown to be a resilient material with its radiation hardness and mechanical strength, while it is also simple due to its wide bandgap removing the need for doping. A new type of diamond based beam position monitor has been constructed, which includes a hole in the center of the diamond where the majority of the beam is intended to pass through. This increases the longevity of the detectors as well as allowing them to be used for high intensity beams. The purpose of this thesis is to evaluate the performance of the detectors in the High Radiation to Materials facility for various beam parameters, involving differences in position, size, bunch intensity and bunch number. A prestudy consisting of calibration of the detectors using single incident particles is also presented. The detectors are shown to work as intended after a recalibration of the algorithm, alb...

  20. Using Ionizing Radiation Detectors. Module 11. Vocational Education Training in Environmental Health Sciences.

    Science.gov (United States)

    Consumer Dynamics Inc., Rockville, MD.

    This module, one of 25 on vocational education training for careers in environmental health occupations, contains self-instructional materials on using ionizing radiation detectors. Following guidelines for students and instructors and an introduction that explains what the student will learn are three lessons: (1) naming and telling the function…

  1. Radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redmayne, I.

    1986-05-21

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed.

  2. Radiation imaging

    International Nuclear Information System (INIS)

    Redmayne, Ian.

    1986-01-01

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed. (author)

  3. UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION

    International Nuclear Information System (INIS)

    Miller, William H.; Manuel Diaz de Leon

    2003-01-01

    A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed

  4. UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    William H. Miller; Manuel Diaz de Leon

    2003-04-15

    A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed.

  5. Fast infrared detectors for beam diagnostics with synchrotron radiation

    International Nuclear Information System (INIS)

    Bocci, A.; Marcelli, A.; Pace, E.; Drago, A.; Piccinini, M.; Cestelli Guidi, M.; De Sio, A.; Sali, D.; Morini, P.; Piotrowski, J.

    2007-01-01

    Beam diagnostic is a fundamental constituent of any particle accelerators either dedicated to high-energy physics or to synchrotron radiation experiments. All storage rings emit radiations. Actually they are high brilliant sources of radiation: the synchrotron radiation emission covers from the infrared range to the X-ray domain with a pulsed structure depending on the temporal characteristics of the stored beam. The time structure of the emitted radiation is extremely useful as a tool to perform time-resolved experiments. However, this radiation can be also used for beam diagnostic to determine the beam stability and to measure the dimensions of the e - or e + beam. Because of the temporal structure of the synchrotron radiation to perform diagnostic, we need very fast detectors. Indeed, the detectors required for the diagnostics of the stored particle bunches at third generation synchrotron radiation sources and FEL need response times in the sub-ns and even ps range. To resolve the bunch length and detect bunch instabilities, X-ray and visible photon detectors may be used achieving response times of a few picoseconds. Recently, photon uncooled infrared devices optimized for the mid-IR range realized with HgCdTe semiconductors allowed to obtain sub-nanosecond response times. These devices can be used for fast detection of intense IRSR sources and for beam diagnostic. We present here preliminary experimental data of the pulsed synchrotron radiation emission of DAΦNE, the electron positron collider of the LNF laboratory of the INFN, performed with new uncooled IR detectors with a time resolution of a few hundreds of picoseconds

  6. Preparation of lithium fluoride for thermoluminescent detectors of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mironenko, S.N.; Nepomnyashchikh, A.I.; Ikrami, D.D.; Paramzin, A.S.; Rakhimov, M.Eh.

    1985-03-01

    The thermostimulated luminescence (TSL) of lithium fluoride monocrystals depending on the method of preparation of starting raw material and features of its preliminary processing is investigated. It is shown that only lithium fluoride of high purity prepared through the stage of formation of hydrofluoride and its subsequent decomposition can be used without any additional processing for manufacturing monocrystal detectors of thermoluminescent dosimetry of the ionizing radiation with low intensity of low temperature peaks.

  7. Low dose radiation damage effects in silicon strip detectors

    International Nuclear Information System (INIS)

    Wiącek, P.; Dąbrowski, W.

    2016-01-01

    The radiation damage effects in silicon segmented detectors caused by X-rays have become recently an important research topic driven mainly by development of new detectors for applications at the European X-ray Free Electron Laser (E-XFEL). However, radiation damage in silicon strip is observed not only after extreme doses up to 1 GGy expected at E-XFEL, but also at doses in the range of tens of Gy, to which the detectors in laboratory instruments like X-ray diffractometers or X-ray spectrometers can be exposed. In this paper we report on investigation of radiation damage effects in a custom developed silicon strip detector used in laboratory diffractometers equipped with X-ray tubes. Our results show that significant degradation of detector performance occurs at low doses, well below 200 Gy, which can be reached during normal operation of laboratory instruments. Degradation of the detector energy resolution can be explained by increasing leakage current and increasing interstrip capacitance of the sensor. Another observed effect caused by accumulation of charge trapped in the surface oxide layer is change of charge division between adjacent strips. In addition, we have observed unexpected anomalies in the annealing process.

  8. Low dose radiation damage effects in silicon strip detectors

    Science.gov (United States)

    Wiącek, P.; Dąbrowski, W.

    2016-11-01

    The radiation damage effects in silicon segmented detectors caused by X-rays have become recently an important research topic driven mainly by development of new detectors for applications at the European X-ray Free Electron Laser (E-XFEL). However, radiation damage in silicon strip is observed not only after extreme doses up to 1 GGy expected at E-XFEL, but also at doses in the range of tens of Gy, to which the detectors in laboratory instruments like X-ray diffractometers or X-ray spectrometers can be exposed. In this paper we report on investigation of radiation damage effects in a custom developed silicon strip detector used in laboratory diffractometers equipped with X-ray tubes. Our results show that significant degradation of detector performance occurs at low doses, well below 200 Gy, which can be reached during normal operation of laboratory instruments. Degradation of the detector energy resolution can be explained by increasing leakage current and increasing interstrip capacitance of the sensor. Another observed effect caused by accumulation of charge trapped in the surface oxide layer is change of charge division between adjacent strips. In addition, we have observed unexpected anomalies in the annealing process.

  9. The pin detector - a simple, robust, cheap and effective nuclear radiation detector

    International Nuclear Information System (INIS)

    Bateman, J.E.

    1984-01-01

    The development of a series of radiation detectors bases on the point anode is reported. Using readily available preformed pins from a variety of electrical connectors as the anodes, a family of devices has been created with useful properties as X-ray detectors, radiation monitors and internal beta counters. A wide variety of gas fillings can be used, argon/CH 4 premix being the most convenient. The structures are robust and call for no precision alignments so keeping costs down. Performance of the devices in respect of sensitivity and pulse height resolution is comparable to that of conventional wire counters. (author)

  10. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15} n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside...

  11. Modeling radiation damage to pixel sensors in the ATLAS detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15}n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside ...

  12. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High- Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for basic...

  13. Superconducting NbN detectors for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, Alexei; Richter, Heiko; Huebers, Heinz-Wilhelm [DLR, Instiute of Planetary Research, Berlin (Germany); Ilin, Konstantin; Siegel, Michael [Institute of Micro- and Nanoelectronic Systems, University of Karlsruhe (Germany)

    2009-07-01

    We present development of a special type of hot-electron bolometers that is designed to optimally detect pulsed synchrotron radiation in the terahertz frequency range. The enlarged log-spiral antenna makes it possible to sense the low-frequency part of the spectrum in coherent and non-coherent regime. The device follows the layout of a typical HEB mixer. The radiation is coupled quasioptically with the 6-mm elliptical silicon lens. The bolometer has the noise equivalent power 2 nW per square root Hz and responds to a few picoseconds long radiation pulse with the electric pulse having full width at half maximum of 160 ps. We present results obtained with this type of detector at different synchrotron facilities and discuss possible improvements of the detector performance.

  14. Radiation flaw detector for testing non-uniform surface bodies of revolution

    International Nuclear Information System (INIS)

    Valevich, M.I.

    1984-01-01

    Radiation flaw detector for testing bodies of revolution with non-uniform surface, welded joints, etc., based on spatial filtration and differentiation of ionizing radiation flux has been described. The calculation of the most important unit of flaw detector - integrators - is made. Experimental studies of the sensitivity have shown, that the radiation flaw detector can be used for rapid testing of products with the sensitivity comparable with the sensitivity of radiographic testing of steel

  15. Fabrication of radiation detector using PbI2 crystals

    International Nuclear Information System (INIS)

    Shoji, T.; Ohba, K.; Suehiro, T.; Hiratate, Y.

    1995-01-01

    Radiation detectors have been fabricated from lead iodide (PbI 2 ) crystals grown by two methods: zone melting and Bridgman methods. In response characteristics of the detector fabricated from crystals grown by the zone melting method, a photopeak for γ-rays from an 241 Am source (59.5 KeV) has been clearly observed with applied detector bias of 500 V at room temperature. The hole drift mobility is estimated to be about 5.5 cm 2 /Vs from measurement of pulse rise time for 5.48 MeV α-rays from 241 Am. By comparing the detector bias versus saturated peak position of the PbI 2 detector with that of CdTe detector, the average energy for producing electron-hole pairs is estimated to be about 8.4 eV for the PbI 2 crystal. A radiation detector fabricated from PbI 2 crystals grown by the Bridgman method, however, exhibited no response for γ-rays

  16. Proton induced target fragmentation studies on solid state nuclear track detectors using Carbon radiators

    Science.gov (United States)

    Szabó, J.; Pálfalvi, J. K.; Strádi, A.; Bilski, P.; Swakoń, J.; Stolarczyk, L.

    2018-04-01

    One of the limiting factors of an astronaut's career is the dose received from space radiation. High energy protons, being the main components of the complex radiation field present on a spacecraft, give a significant contribution to the dose. To investigate the behavior of solid state nuclear track detectors (SSNTDs) if they are irradiated by such particles, SSNTD stacks containing carbon blocks were exposed to high energy proton beams (70, 100, 150 and 230 MeV) at the Proteus cyclotron, IFJ PAN -Krakow. The incident protons cannot be detected directly; however, tracks of secondary particles, recoils and fragments of the constituent atoms of the detector material and of the carbon radiator are formed. It was found that as the proton energy increases, the number of tracks induced in the PADC material by secondary particles decreases. From the measured geometrical parameters of the tracks the linear energy transfer (LET) spectrum and the dosimetric quantities were determined, applying appropriate calibration. In the LET spectra the LET range of the most important secondary particles could be identified and their abundance showed differences in the spectra if the detectors were short or long etched. The LET spectra obtained on the SSNTDs irradiated by protons were compared to LET spectra of detectors flown on the International Space Station (ISS): they were quite similar, resulting in a quality factor difference of only 5%. Thermoluminescent detectors (TLDs) were applied in each case to measure the dose from primary protons and other lower LET particles present in space. Comparing and analyzing the results of the TLD and SSNTD measurements, it was obtained that proton induced target fragments contributed to the total absorbed dose in 3.2% and to the dose equivalent in 14.2% in this particular space experiment.

  17. A semiconductor parameter analyzer for ionizing radiation detectors

    International Nuclear Information System (INIS)

    Santos, Luiz A.P.

    2009-01-01

    Electrometers and ion chamber are normally used to make several types of measurements in a radiation field and there is a unique voltage applied to each detector type. Some electronic devices that are built of semiconductor materials like silicon crystal can also be used for the same purpose. In this case, a characteristic curve of the device must be acquired to choose an operation point which consists of an electrical current or voltage to be applied to the device. Unlike ion chambers, such an electronic device can have different operation points depending on its current versus voltage curve (I x V). The best operation point of the device is also a function of the radiation, energy, dose rate and fluence. The purpose of this work is to show a semiconductor parameter analyzer built to acquire I x V curves as usually, and the innovation here is the fact that it can be used to obtain such a parametric curve when a quad-polar device is under irradiation. The results demonstrate that the system is a very important tool to scientists interested to evaluate a semiconductor detector before, during and after irradiation. A collection of results for devices under an X-ray beam and a neutron fluence are presented: photodiode, phototransistors, bipolar transistor and MOSFET. (author)

  18. Current trends in scintillator detectors and materials

    International Nuclear Information System (INIS)

    Moses, W.W.

    2002-01-01

    The last decade has seen a renaissance in inorganic scintillator development for gamma ray detection. Lead tungstate (PbWO 4 ) has been developed for high-energy physics experiments, and possesses exceptionally high density and radiation hardness, albeit with low luminous efficiency. Lutetium orthosilicate or LSO (Lu 2 SiO 5 :Ce) possesses a unique combination of high luminous efficiency, high density, and reasonably short decay time, and is now incorporated in commercial positron emission tomography cameras. There have been advances in understanding the fundamental mechanisms that limit energy resolution, and several recently discovered materials (such as LaBr 3 :Ce) possess energy resolution that approaches that of direct solid state detectors. Finally, there are indications that a neglected class of scintillator materials that exhibit near band-edge fluorescence could provide scintillators with sub-nanosecond decay times and high luminescent efficiency

  19. Study of radiation damage in solid materials by simulating physical processes

    International Nuclear Information System (INIS)

    Pinnera Hernandez, Ibrahin

    2006-12-01

    Nowadays the damage induced by different types of radiation in advanced materials is widely studied. Especially those materials involved in experiments and developing of new technologies, such as high critical temperature superconductors, semiconductors, metals. These materials are the basis constituents of radiation detectors, particle accelerators, etc. One way of studying this kind of damage is through the determination of the displacements per atom (dpa) induced by the radiation in these materials. This magnitude is one of the measures of the provoked radiation damage. On this direction, the present thesis deals with the study of two types of materials through mathematical simulation of physical processes taking place in the radiation transport. Ceramic superconductor Yba 2 Cu 3 O 7-x and metal Fe are the selected materials. The energy range of the incident gamma radiation goes from a few keV to 15 MeV. The MCNPX version 2.6b is used to determine the physical magnitudes required to calculate the distribution of displacements per atom within these materials, using an algorithm implemented for this purpose. Finally, a comparison between the obtained dpa profiles and the corresponding of energy deposition by radiation in these same materials and the possible linear dependence between both quantities is discussed. (Author)

  20. Non-Linear Optical Phenomena in Detecting Materials as a Possibility for Fast Timing in Detectors of Ionizing Radiation

    CERN Document Server

    Korjik, M. V.; Buganov, O.; Fedorov, A. A.; Emelianchik, I.; Griesmayer, E.; Mechinsky, V.; Nargelas, S.; Sidletskiy, O.; Tamulaitis, G.; Tikhomirov, S. N.; Vaitkevicius, A.

    2016-01-01

    The time resolution of the detectors currently in use is limited by 50-70 ps due to the spontaneous processes involved in the development of the response signal, which forms after the relaxation of carriers generated during the interaction. In this study, we investigate the feasibility of exploiting sub-picosecond phenomena occurring after the interaction of scintillator material with ionizing radiation by probing the material with ultra-short laser pulses. One of the phenomena is the elastic polarization due to the local lattice distortion caused by the displacement of electrons and holes generated by ionization. The key feature of the elastic polarization is its short response time, which makes it prospective for using as an optically detectable time mark. The nonlinear optical absorption of femtosecond light pulses of appropriate wavelength is demonstrated to be a prospective tool to form the mark. This study was aimed at searching for inorganic crystalline media combining scintillation properties and non-...

  1. Radiative sky cooling: fundamental physics, materials, structures, and applications

    Directory of Open Access Journals (Sweden)

    Sun Xingshu

    2017-07-01

    Full Text Available Radiative sky cooling reduces the temperature of a system by promoting heat exchange with the sky; its key advantage is that no input energy is required. We will review the origins of radiative sky cooling from ancient times to the modern day, and illustrate how the fundamental physics of radiative cooling calls for a combination of properties that may not occur in bulk materials. A detailed comparison with recent modeling and experiments on nanophotonic structures will then illustrate the advantages of this recently emerging approach. Potential applications of these radiative cooling materials to a variety of temperature-sensitive optoelectronic devices, such as photovoltaics, thermophotovoltaics, rectennas, and infrared detectors, will then be discussed. This review will conclude by forecasting the prospects for the field as a whole in both terrestrial and space-based systems.

  2. Exploring graphene field effect transistor devices to improve spectral resolution of semiconductor radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Richard Karl [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Howell, Stephen Wayne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Jeffrey B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hamilton, Allister B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2013-12-01

    Graphene, a planar, atomically thin form of carbon, has unique electrical and material properties that could enable new high performance semiconductor devices. Graphene could be of specific interest in the development of room-temperature, high-resolution semiconductor radiation spectrometers. Incorporating graphene into a field-effect transistor architecture could provide an extremely high sensitivity readout mechanism for sensing charge carriers in a semiconductor detector, thus enabling the fabrication of a sensitive radiation sensor. In addition, the field effect transistor architecture allows us to sense only a single charge carrier type, such as electrons. This is an advantage for room-temperature semiconductor radiation detectors, which often suffer from significant hole trapping. Here we report on initial efforts towards device fabrication and proof-of-concept testing. This work investigates the use of graphene transferred onto silicon and silicon carbide, and the response of these fabricated graphene field effect transistor devices to stimuli such as light and alpha radiation.

  3. 3-D GaAs radiation detectors

    International Nuclear Information System (INIS)

    Meikle, A.R.; Bates, R.L.; Ledingham, K.; Marsh, J.H.; Mathieson, K.; O'Shea, V.; Smith, K.M.

    2002-01-01

    A novel type of GaAs radiation detector featuring a 3-D array of electrodes that penetrate through the detector bulk is described. The development of the technology to fabricate such a detector is presented along with electrical and radiation source tests. Simulations of the electrical characteristics are given for detectors of various dimensions. Laser drilling, wet chemical etching and metal evaporation were used to create a cell array of nine electrodes, each with a diameter of 60 μm and a pitch of 210 μm. Electrical measurements showed I-V characteristics with low leakage currents and high breakdown voltages. The forward and reverse I-V measurements showed asymmetrical characteristics, which are not seen in planar diodes. Spectra were obtained using alpha particle illumination. A charge collection efficiency of 50% and a S/N ratio of 3 : 1 were obtained. Simulations using the MEDICI software package were performed on cells with various dimensions and were comparable with experimental results. Simulations of a nine-electrode cell with 10 μm electrodes with a 25 μm pitch were also performed. The I-V characteristics again showed a high breakdown voltage with a low leakage current but also showed a full depletion voltage of just 8 V

  4. Performance of semiconductor radiation sensors for simple and low-cost radiation detector

    International Nuclear Information System (INIS)

    Tanimura, Yoshihiko; Birumachi, Atsushi; Yoshida, Makoto; Watanabe, Tamaki

    2008-01-01

    In order to develop a simple but reliable radiation detector for the general public, photon detection performances of radiation sensors have been studied in photon calibration fields and by Monte Carlo simulations. A silicon p-i-n photodiode and a CdTe detector were selected for the low cost sensors. Their energy responses to ambient dose equivalent H * (10) were evaluated over the energy range from 60 keV to 2 MeV. The response of the CdTe decreases markedly with increasing photon energy. On the other hand, the photodiode has the advantage of almost flat response above 150 keV. The sensitivities of these sensors are 4 to 6 cpm for the natural radiation. Detection limits of the radiation level are low enough to know the extreme increase of radiation due to emergency situations of nuclear power plants, fuel treatment facilities and so on. (author)

  5. Silicon detectors for x and gamma-ray with high radiation resistance

    International Nuclear Information System (INIS)

    Cimpoca, Valerica; Popescu, Ion V.; Ruscu, Radu

    2001-01-01

    Silicon detectors are widely used in X and gamma-ray spectroscopy for direct detection or coupled with scintillators in high energy nuclear physics (modern collider experiments are representative), medicine and industrial applications. In X and gamma dosimetry, a low detection limit (under 6 KeV) with silicon detectors becomes available. Work at the room temperature is now possible due to the silicon processing evolution, which assures low reverse current and high life time of carriers. For several years, modern semiconductor detectors have been the primary choice for the measurement of nuclear radiation in various scientific fields. Nowadays the recently developed high resolution silicon detectors found their way in medical applications. As a consequence many efforts have been devoted to the development of high sensitivity and radiation hardened X and gamma-ray detectors for the energy range of 5 - 150 keV. The paper presents some results concerning the technology and behaviour of X and Gamma ray silicon detectors used in physics research, industrial and medical radiography. The electrical characteristics of these detectors, their modification after exposure to radiation and the results of spectroscopic X and Gamma-ray measurements are discussed. The results indicated that the proposed detectors enables the development of reliable silicon detectors to be used in controlling the low and high radiation levels encountered in a lot of application

  6. Physics of scintillation detectors

    International Nuclear Information System (INIS)

    Novotny, R.

    1991-01-01

    The general concept of a radiation detector is based on three fundamental principles: sensitivity of the device to the radiation of interest which requires a large cross-section in the detector material, detector response function to the physical properties of the radiation. As an example, a scintillation detector for charged particles should allow to identify the charge of the particle, its kinetic energy and the time of impact combined with optimum resolutions. Optimum conversion of the detector response (like luminescence of a scintillator) into electronical signals for further processing. The following article will concentrate on the various aspects of the first two listed principles as far as they appear to be relevant for photon and charged particle detection using organic and inorganic scintillation detectors. (orig.)

  7. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm^2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for b...

  8. Modeling radiation damage to pixel sensors in the ATLAS detector

    Science.gov (United States)

    Ducourthial, A.

    2018-03-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC) . As the closest detector component to the interaction point, these detectors will be subject to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC) [1], the innermost layers will receive a fluence in excess of 1015 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is essential in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects on the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside early studies with LHC Run 2 proton-proton collision data.

  9. Evaluation of effects of ionizing radiation on materials used in dental restorations

    International Nuclear Information System (INIS)

    Maio, Mireia Florencio

    2009-01-01

    This work consisted of quantitative studies of the effects caused by ionizing radiation on materials used in dental restorations (Titanium, Amalgam, Resin Composite and Glass Ionomer) aiming the deleterious effects of radiotherapy when patients with tumors in head and neck, arising when the teeth are restored within in the field of radiation. Samples were submitted to X-ray beams of 6 MV from a linear accelerator, VARIAN 2100C model. The samples were analyzed by X-ray fluorescence techniques to compare the chemical composition before and after the irradiation. The sample were submitted to Geiger-Mueller detectors and the ionization chambers in order to verify any residual radiation in the samples. The samples were also analyzed by gamma spectrometry by a Germanium detector. These tests were performed to determine small changes in the composition in the samples due to the radiation interaction. The results of this study may encourage the development of new research for alternative materials in dental restorations that can contribute to improve the quality of life of those patients with tumors of the mouth. (author)

  10. Study of radiation detectors response in standard X, gamma and beta radiation standard beams

    International Nuclear Information System (INIS)

    Nonato, Fernanda Beatrice Conceicao

    2010-01-01

    The response of 76 Geiger-Mueller detectors, 4 semiconductor detectors and 34 ionization chambers were studied. Many of them were calibrated with gamma radiation beams ( 37 Cs and 60 Co), and some of them were tested in beta radiation ( 90 Sr+ 9' 0Y e 204 Tl) and X radiation (N-60, N-80, N-100, N-150) beams. For all three types of radiation, the calibration factors of the instruments were obtained, and the energy and angular dependences were studied. For beta and gamma radiation, the angular dependence was studied for incident radiation angles of 0 deg and +- 45 deg. The curves of the response of the instruments were obtained over an angle interval of 0 deg to +- 90 deg, for gamma, beta and X radiations. The calibration factors obtained for beta radiation were compared to those obtained for gamma radiation. For gamma radiation, 24 of the 66 tested Geiger-Mueller detectors presented results for the energy dependence according to international recommendation of ISO 4037-2 and 56 were in accordance with the Brazilian ABNT 10011 recommendation. The ionization chambers and semiconductors were in accordance to national and international recommendations. All instruments showed angular dependence less than 40%. For beta radiation, the instruments showed unsatisfactory results for the energy dependence and angular dependence. For X radiation, the ionization chambers presented results for energy dependence according to the national recommendation, and the angular dependence was less than 40%. (author)

  11. Performance And Radiation Hardness Of The Atlas/sct Detector Module

    CERN Document Server

    Eklund, L

    2003-01-01

    The ATLAS experiment is a general purpose experiment being constructed at the Large Hadron Collider (LHC) at FERN, Geneva. ATLAS is designed to exploit the full physics potential of LHC, in particular to study topics concerning the Higgs mechanism, Super-symmetry and CP violation. The cross sections for the processes under study are extremely small, requiring very high luminosity colliding beams. The Semiconductor Tracker (SCT) is an essential part of the Inner Detector tracking system of ATLAS. The active elements of the SCT is 4088 detector modules, tiled on four barrel cylinders and eighteen endcap disks. As a consequence of the high luminosity, the detector modules will operate in a harsh radiation environment. This thesis describes work concerning radiation hardness, beam test performance and methods for production testing of detector modules. The radiation hardness studies have been focused on the electrical performance of the front-end ASIC and the detector module. The results have identified features ...

  12. Development of radiation tolerant semiconductor detectors for the Super-LHC

    CERN Document Server

    Moll, M; Al-Ajili, A A; Alfieri, G; Allport, P P; Artuso, M; Assouak, S; Avset, B S; Barabash, L; Barcz, A; Bates, R; Biagi, S F; Bilei, G M; Bisello, D; Blue, A; Blumenau, A; Boisvert, V; Bölla, G; Bondarenko, G B; Borchi, E; Borrello, L; Bortoletto, D; Boscardin, M; Bosisio, L; Bowcock, T J V; Brodbeck, T J; Broz, J; Bruzzi, M; Brzozowski, A; Buda, M; Buhmann, P; Buttar, C; Campabadal, F; Campbell, D; Candelori, A; Casse, G; Cavallini, A; Charron, S; Chilingarov, A; Chren, D; Cindro, V; Collins, P; Coluccia, R; Contarato, D; Coutinho, J; Creanza, D; Cunningham, W; Betta, G F D; Dawson, I; de Boer, Wim; De Palma, M; Demina, R; Dervan, P; Dittongo, S; Dolezal, Z; Dolgolenko, A; Eberlein, T; Eremin, V; Fall, C; Fasolo, F; Fizzotti, F; Fleta, C; Focardi, E; Forton, E; Fretwurst, E; García, C; García-Navarro, J E; Gaubas, E; Genest, M H; Gill, K A; Giolo, K; Glaser, M; Gössling, C; Golovine, V; Sevilla, S G; Gorelov, I; Goss, J; Bates, A G; Grégoire, G; Gregori, P; Grigoriev, E; Grillo, A A; Groza, A; Guskov, J; Haddad, L; Härkönen, J; Hauler, F; Hoeferkamp, M; Honniger, F; Horazdovsky, T; Horisberger, Roland Paul; Horn, M; Houdayer, A; Hourahine, B; Hughes, G; Ilyashenko, Yu S; Irmscher, K; Ivanov, A; Jarasiunas, K; Johansen, K M H; Jones, B K; Jones, R; Joram, C; Jungermann, L; Kalinina, E; Kaminski, P; Karpenko, A; Karpov, A; Kazlauskiene, V; Kazukauskas, V; Khivrich, V; Khomenkov, V; Kierstead, J A; Klaiber Lodewigs, J; Klingenberg, R; Kodys, P; Kohout, Z; Korjenevski, S; Koski, M; Kozlowski, R; Kozodaev, M; Kramberger, G; Krasel, O; Kuznetsov, A; Kwan, S; Lagomarsino, S; Lassila-Perini, K M; Lastovetsky, V F; Latino, G; Lazanu, S; Lazanu, I; Lebedev, A; Lebel, C; Leinonen, K; Leroy, C; Li Z; Lindström, G; Linhart, V; Litovchenko, A P; Litovchenko, P G; Lo Giudice, A; Lozano, M; Luczynski, Z; Luukka, P; Macchiolo, A; Makarenko, L F; Mandic, I; Manfredotti, C; Manna, N; Garcia, S Mi; Marunko, S; Mathieson, K; Melone, J; Menichelli, D; Messineo, A; Metcalfe, J; Miglio, S; Mikuz, M; Miyamoto, J; Monakhov, E; Moscatelli, F; Naoumov, D; Nossarzhevska, E; Nysten, J; Olivero, P; OShea, V; Palviainen, T; Paolini, C; Parkes, C; Passeri, D; Pein, U; Pellegrini, G; Perera, L; Petasecca, M; Piemonte, C; Pignatel, G U; Pinho, N; Pintilie, I; Pintilie, L; Polivtsev, L; Polozov, P; Popa, A; Popule, J; Pospísil, S; Pozza, A; Radicci, V; Rafí, J M; Rando, R; Röder, R; Rohe, T; Ronchin, S; Rott, C; Roy, A; Ruzin, A; Sadrozinski, H F W; Sakalauskas, S; Scaringella, M; Schiavulli, L; Schnetzer, S; Schumm, B; Sciortino, S; Scorzoni, A; Segneri, G; Seidel, S; Seiden, A; Sellberg, G; Sellin, P J; Sentenac, D; Shipsey, I; Sícho, P; Sloan, T; Solar, M; Son, S; Sopko, B; Sopko, V; Spencer, N; Stahl, J; Stolze, D; Stone, R; Storasta, J; Strokan, N; Sudzius, M; Surma, B; Suvorov, A; Svensson, B G; Tipton, P; Tomasek, M; Tsvetkov, A; Tuominen, E; Tuovinen, E; Tuuva, T; Tylchin, M; Uebersee, H; Uher, J; Ullán, M; Vaitkus, J V; Velthuis, J; Verbitskaya, E; Vrba, V; Wagner, G; Wilhelm, I; Worm, S; Wright, V; Wunstorf, R; Yiuri, Y; Zabierowski, P; Zaluzhny, A; Zavrtanik, M; Zen, M; Zhukov, V; Zorzi, N

    2005-01-01

    The envisaged upgrade of the Large Hadron Collider (LHC) at CERN towards the Super-LHC (SLHC) with a 10 times increased luminosity of 10challenges for the tracking detectors of the SLHC experiments. Unprecedented high radiation levels and track densities and a reduced bunch crossing time in the order of 10ns as well as the need for cost effective detectors have called for an intensive R&D program. The CERN RD50 collaboration "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" is working on the development of semiconductor sensors matching the requirements of the SLHC. Sensors based on defect engineered silicon like Czochralski, epitaxial and oxygen enriched silicon have been developed. With 3D, Semi-3D and thin detectors new detector concepts have been evaluated and a study on the use of standard and oxygen enriched p-type silicon detectors revealed a promising approach for radiation tolerant cost effective devices. These and other most recent advancements of the RD50 ...

  13. A large area transition radiation detector for the NOMAD experiment

    Science.gov (United States)

    Bassompierre, G.; Bermond, M.; Berthet, M.; Bertozzi, T.; Détraz, C.; Dubois, J.-M.; Dumps, L.; Engster, C.; Fazio, T.; Gaillard, G.; Gaillard, J.-M.; Gouanère, M.; Manola-Poggioli, E.; Mossuz, L.; Mendiburu, J.-P.; Nédélec, P.; Palazzini, E.; Pessard, H.; Petit, P.; Petitpas, P.; Placci, A.; Sillou, D.; Sottile, R.; Valuev, V.; Verkindt, D.; Vey, H.; Wachnik, M.

    1998-02-01

    A transition radiation detector to identify electrons at 90% efficiency with a rejection factor against pions of 10 3 on an area of 2.85 × 2.85 m 2 has been constructed for the NOMAD experiment. Each of its 9 modules includes a 315 plastic foil radiator and a detector plane of 176 vertical straw tubes filled with a xenon-methane gas mixture. Details of the design, construction and operation of the detector are given.

  14. A large area transition radiation detector for the NOMAD experiment

    CERN Document Server

    Bassompierre, Gabriel; Berthet, M; Bertozzi, T; Détraz, C; Dubois, J M; Dumps, Ludwig; Engster, Claude; Fazio, T; Gaillard, G; Gaillard, Jean-Marc; Gouanère, M; Manola-Poggioli, E; Mossuz, L; Mendiburu, J P; Nédélec, P; Palazzini, E; Pessard, H; Petit, P; Petitpas, P; Placci, Alfredo; Sillou, D; Sottile, R; Valuev, V Yu; Verkindt, D; Vey, H; Wachnik, M

    1997-01-01

    A transition radiation detector to identify electrons at 90% efficiency with a rejection factor against pions of 10 3 on an area of 2.85 × 2.85 m 2 has been constructed for the NOMAD experiment. Each of its 9 modules includes a 315 plastic foil radiator and a detector plane of 176 vertical straw tubes filled with a xenon-methane gas mixture. Details of the design, construction and operation of the detector are given.

  15. CONCORD: comparison of cosmic radiation detectors in the radiation field at aviation altitudes

    Czech Academy of Sciences Publication Activity Database

    Meier, M.; Trompier, F.; Ambrožová, Iva; Kubančák, Ján; Matthia, D.; Ploc, Ondřej; Santen, N.; Wirtz, M.

    2016-01-01

    Roč. 6, MAY (2016), A24 ISSN 2115-7251 Institutional support: RVO:61389005 Keywords : aviation * radiation exposure of aircrew * comparison of radiation detectors * galactic cosmic radiation * ambient dose equivalent Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.446, year: 2016

  16. Improved Growth Methods for LaBr3 Scintillation Radiation Detectors

    International Nuclear Information System (INIS)

    McGregor, Douglas S.

    2011-01-01

    The objective is to develop advanced materials for deployment as high-resolution gamma ray detectors. Both LaBr3 and CeBr3 are advanced scintillation materials, and will be studied in this research. Prototype devices, in collaboration Sandia National Laboratories, will be demonstrated along with recommendations for mass production and deployment. It is anticipated that improved methods of crystal growth will yield larger single crystals of LaBr3 for deployable room-temperature operated gamma radiation spectrometers. The growth methods will be characterized. The LaBr3 and CeBr3 scintillation crystals will be characterized for light yield, spectral resolution, and for hardness.

  17. Energy nonlinearity in radiation detection materials: Causes and consequences

    International Nuclear Information System (INIS)

    Jaffe, J.E.; Jordan, D.V.; Peurrung, A.J.

    2007-01-01

    The phenomenology and present theoretical understanding of energy nonlinearity (nonproportionality) in radiation detection materials is reviewed, with emphasis on gamma-ray spectroscopy. Scintillators display varying degrees and patterns of nonlinearity, while semiconductor detectors are extremely linear, and gas detectors show a characteristic form of nonproportionality associated with core levels. The relation between nonlinear response (to both primary particles and secondary electrons) and spectrometer resolution is also discussed. We review the qualitative ideas about the origin of nonlinearity in scintillators that have been proposed to date, with emphasis on transport and recombination of electronic excitations. Recent computational and experimental work on the basic physics of scintillators is leading towards a better understanding of energy nonlinearity and should result in new, more linear scintillator materials in the near future

  18. Radiation detector device for measuring ionizing radiation

    International Nuclear Information System (INIS)

    Brake, D. von der.

    1983-01-01

    The device contains a compensating filter circuit, which guarantees measurement of the radiation dose independent of the energy or independent of the energy and direction. The compensating filter circuit contains a carrier tube of a slightly absorbing metal with an order number not higher than 35, which surrounds a tubular detector and which carries several annular filter parts on its surface. (orig./HP) [de

  19. Neutron radiation damage studies on silicon detectors

    International Nuclear Information System (INIS)

    Li, Zheng; Chen, W.; Kraner, H.W.

    1990-10-01

    Effects of neutron radiation on electrical properties of Si detectors have been studied. At high neutron fluence (Φ n ≥ 10 12 n/cm 2 ), C-V characteristics of detectors with high resistivities (ρ ≥ 1 kΩ-cm) become frequency dependent. A two-trap level model describing this frequency dependent effect is proposed. Room temperature anneal of neutron damaged (at LN 2 temperature) detectors shows three anneal stages, while only two anneal stages were observed in elevated temperature anneal. 19 refs., 14 figs

  20. Development of a Compact Gamma-ray Detector for a Neural-Network Radiation Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H. S.; Ha, J. H.; Lee, K. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, C. H. [Hanyang Univ., Seoul (Korea, Republic of)

    2012-03-15

    Radiation monitoring is very important to secure safety in nuclear-related facilities and against nuclear terrorism. For wide range of radiation monitoring, neutral network system of radiation detection is most efficient way. Thus, a compact radiation detector is useful to install in wide range to be concerned. A compact gamma-ray detector was fabricated by using a CsI(Tl) scintillator, which was matched with the formerly developed PIN photodiode, for a neural network radiation monitoring. At room temperature, the fabricated compact gamma-ray detector demonstrates an energy resolution of 13.3 % for 662 keV 6.9% for 1330 keV. The compactness, the low-voltage power consumption and the physical hardness are very useful features for a neural network radiation monitoring. In this study, characteristics of a fabricated compact gamma-ray detector were presented. An important aspect to consider in a neural-network radiation monitoring such as reaction probability of the fabricated compact detector for angle of incident gamma-ray was also addressed.

  1. Characteristics for heavy ions and micro-dosimetry in radiation detectors

    International Nuclear Information System (INIS)

    Doke, Tadayoshi

    1978-01-01

    The characteristics of radiation detectors for heavy ions generally present more complex aspects as compared with those for electron beam and γ-ray. There is the ''Katz theory'' applying the target theory in radiobiology phenomenologically to radiation detectors. Here, first, the Katz theory for radiation detectors is explained, then its applications to nuclear plates, solid state track detectors, scintillation detectors and thermoluminescence dosimeters are described, respectively. The theory is used for the calibration of the nuclear charge of heavy ions in nuclear plates and recently is used to simulate the flight tracks of heavy ions or magnetic monopoles. In solid state track detectors, the threshold value of the energy given along the tracks of heavy ions is inherent to a detector, and the Katz theory is applicable as the measure of the threshold. The theory seems to be superior to the other methods. However, it has disadvantages that the calculation is not simple and is difficult for wide objects. In scintillation detectors, the scintillation efficiency is not a single function of dE/dx, but depends on the kinds of heavy ions, which Katz succeeded to describe quantitatively with his theory. Such result has also been produced that the dependence of thermoluminescence dosimeters such as LiF on LET by Katz theory agreed fairly well with experiments. (Wakatsuki, Y.)

  2. Two-dimensional readout system for radiation detector

    International Nuclear Information System (INIS)

    Lee, L.Y.

    1975-01-01

    A two dimensional readout system has been provided for reading out locations of scintillations produced in a scintillation type radiation detector array wherein strips of scintillator material are arranged in a parallel planar array. Two sets of light guides are placed perpendicular to the scintillator strips, one on the top and one on the bottom to extend in alignment across the strips. Both the top and bottom guides are composed of a number of 90 0 triangular prisms with the lateral side forming the hypotenuse equal to twice the width of a scintillator strip. The prism system reflects light from a scintillation along one of the strips back and forth through adjacent strips to light pipes coupled to the outermost strips of the detector array which transmit light pulses to appropriate detectors to determine the scintillation along one axis. Other light pipes are connected to the end portions of the strips to transmit light from the individual strips to appropriate light detectors to indicate the particular strip activated, thereby determining the position of a scintillation along the other axis. The number of light guide pairs may be equal the number of the scintillation strips when equal spatial resolution for each of the two coordinates is desired. When the scintillator array detects an event which produces a scintillation along one of the strips, the emitted light travels along four different paths, two of which are along the strip, and two of which are through the light guide pair perpendicular to the strips until all four beams reach the outer edges of the array where they may be transmitted to light detectors by means of light pipes connected therebetween according to a binary code for direct digital readout. (U.S.)

  3. The HERMES dual-radiator ring imaging Cherenkov detector

    CERN Document Server

    Akopov, N; Bailey, K; Bernreuther, S; Bianchi, N; Capitani, G P; Carter, P; Cisbani, E; De Leo, R; De Sanctis, E; De Schepper, D; Dzhordzhadze, V; Filippone, B W; Frullani, S; Garibaldi, F; Hansen, J O; Hommez, B; Iodice, M; Jackson, H E; Jung, P; Kaiser, R; Kanesaka, J; Kowalczyk, R; Lagamba, L; Maas, A; Muccifora, V; Nappi, E; Negodaeva, K; Nowak, Wolf-Dieter; O'Connor, T; O'Neill, T G; Potterveld, D H; Ryckbosch, D; Sakemi, Y; Sato, F; Schwind, A; Shibata, T A; Suetsugu, K; Thomas, E; Tytgat, M; Urciuoli, G M; Van De Kerckhove, K; Van De Vyver, R; Yoneyama, S; Zhang, L F; Zohrabyan, H G

    2002-01-01

    The construction and use of a dual radiator Ring Imaging Cherenkov (RICH) detector is described. This instrument was developed for the HERMES experiment at DESY which emphasises measurements of semi-inclusive deep-inelastic scattering. It provides particle identification for pions, kaons, and protons in the momentum range from 2 to 15 GeV, which is essential to these studies. The instrument uses two radiators, C sub 4 F sub 1 sub 0 , a heavy fluorocarbon gas, and a wall of silica aerogel tiles. The use of aerogel in a RICH detector has only recently become possible with the development of clear, large, homogeneous and hydrophobic aerogel. A lightweight mirror was constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality. The photon detector consists of 1934 photomultiplier tubes (PMT) for each detector half, held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet.

  4. Gold-coated copper cone detector as a new standard detector for F2 laser radiation at 157 nm

    International Nuclear Information System (INIS)

    Kueck, Stefan; Brandt, Friedhelm; Taddeo, Mario

    2005-01-01

    A new standard detector for high-accuracy measurements of F2 laser radiation at 157 nm is presented. This gold-coated copper cone detector permits the measurement of average powers up to 2 W with an uncertainty of ∼1%. To the best of our knowledge, this is the first highly accurate standard detector for F2 laser radiation for this power level. It is fully characterized according to Guide to the Expression of Uncertainty in Measurement of the International Organization for Standardization and is connected to the calibration chain for laser radiation established by the German National Metrology Institute

  5. Evaluation of a digital optical ionizing radiation particle track detector

    International Nuclear Information System (INIS)

    Hunter, S.R.

    1987-06-01

    An ionizing radiation particle track detector is outlined which can, in principle, determine the three-dimensional spatial distribution of all the secondary electrons produced by the passage of ionizing radiation through a low-pressure (0.1 to 10 kPa) gas. The electrons in the particle track are excited by the presence of a high-frequency AC electric field, and two digital cameras image the optical radiation produced in electronic excitation collisions of the surroundings gas by the electrons. The specific requirements of the detector for neutron dosimetry and microdosimetry are outlined (i.e., operating conditions of the digital cameras, high voltage fields, gas mixtures, etc.) along with an estimate of the resolution and sensitivity achievable with this technique. The proposed detector is shown to compare favorable with other methods for obtaining the details of the track structure, particularly in the quality of the information obtainable about the particle track and the comparative simplicity and adaptability of the detector for measuring the secondary electron track structure for many forms of ionizing radiation over a wide range of energies

  6. Locating gamma radiation source by self collimating BGO detector system

    Energy Technology Data Exchange (ETDEWEB)

    Orion, I; Pernick, A; Ilzycer, D; Zafrir, H [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center; Shani, G [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

    1996-12-01

    The need for airborne collimated gamma detector system to estimate the radiation released from a nuclear accident has been established. A BGO detector system has been developed as an array of separate seven cylindrical Bismuth Germanate scintillators, one central detector symmetrically surrounded by six detectors. In such an arrangement, each of the detectors reduced the exposure of other detectors in the array to a radiation incident from a possible specific spatial angle, around file array. This shielding property defined as `self-collimation`, differs the point source response function for each of the detectors. The BGO detector system has a high density and atomic number, and therefore provides efficient self-collimation. Using the response functions of the separate detectors enables locating point sources as well as the direction of a nuclear radioactive plume with satisfactory angular resolution, of about 10 degrees. The detector`s point source response, as function of the source direction, in a horizontal plane, has been predicted by analytical calculation, and was verified by Monte-Carlo simulation using the code EGS4. The detector`s response was tested in a laboratory-scale experiment for several gamma ray energies, and the experimental results validated the theoretical (analytical and Monte-Carlo) results. (authors).

  7. Modern gas-avalanche radiation detectors: from innovations to applications

    International Nuclear Information System (INIS)

    2013-01-01

    Micro-Pattern Gaseous Detectors (MPGD) technologies allow for the conception of advanced large area radiation detectors with unprecedented spatial resolutions and sensitivities, capable of operating under very high radiation flux. After more than two decades of extensive R and D carried by large number of groups worldwide, these detector technologies have reached high level of maturity. Nowadays, they are adapted as leading instruments for a growing number of applications in particle physics and in many other fields on basic and applied research. The growing interest in MPGD technologies and their mass-production capabilities naturally motivates further developments in the field. The state-of-the-art detector concepts and technologies have been introduced and their evolution, properties and current leading applications have been reviewed. Future potential applications as well as new technology challenges have been discussed

  8. Mobile robot prototype detector of gamma radiation

    International Nuclear Information System (INIS)

    Vazquez C, R.M.; Duran V, M. D.; Jardon M, C. I.

    2014-10-01

    In this paper the technological development of a mobile robot prototype detector of gamma radiation is shown. This prototype has been developed for the purpose of algorithms implementation for the applications of terrestrial radiation monitoring of exposed sources, search for missing radioactive sources, identification and delineation of radioactive contamination areas and distribution maps generating of radioactive exposure. Mobile robot detector of radiation is an experimental technology development platform to operate in laboratory environment or flat floor facilities. The prototype integrates a driving section of differential configuration robot on wheels, a support mechanism and rotation of shielded detector, actuator controller cards, acquisition and processing of sensor data, detection algorithms programming and control actuators, data recording (Data Logger) and data transmission in wireless way. The robot in this first phase is remotely operated in wireless way with a range of approximately 150 m line of sight and can extend that range to 300 m or more with the use of signal repeaters. The gamma radiation detection is performed using a Geiger detector shielded. Scan detection is performed at various time sampling periods and diverse positions of discrete or continuous angular orientation on the horizon. The captured data are geographical coordinates of robot GPS (latitude and longitude), orientation angle of shield, counting by sampling time, date, hours, minutes and seconds. The data is saved in a file in the Micro Sd memory on the robot. They are also sent in wireless way by an X Bee card to a remote station that receives for their online monitoring on a laptop through an acquisition program by serial port on Mat Lab. Additionally a voice synthesizing card with a horn, both in the robot, periodically pronounced in Spanish, data length, latitude, orientation angle of shield and detected accounts. (Author)

  9. Instrumentation measurement and testing complex for detection and identification of radioactive materials using the emitted radiation

    International Nuclear Information System (INIS)

    Samossadny, V.T.; Dmitrenko, V.V.; Kadlin, V.V.; Kolesnikov, S.V.; Ulin, S.E.; Grachev, V.M.; Vlasik, K.F.; Dedenko, G.L.; Novikov, D.V.; Uteshev, Z.M.

    2006-01-01

    Simultaneous measurement of neutron and gamma radiation is a very usefull method for effective nuclear materials identification and control. The gamma-ray-neutron complex described in the paper is based on two multi-layer 3 He neutrons detectors and two High Pressure Xenon gamma-ray spectrometers assembled in one unit. All these detectors were callibrated on neutron and gamma-ray sources. The main characteristics of the instrumentation , its testing results and gamma-ray and neutron radiation parameters, which have been measured are represented in the paper. The gamma-neutron sources and fissile materials reliable detection and identification capability was demonstrated

  10. Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

    International Nuclear Information System (INIS)

    Moll, M.; Fretwurst, E.; Lindstroem, G.

    2000-01-01

    We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2x10 14 to 9x10 17 cm -3 have been irradiated with fast neutrons up to a fluence of 2x10 15 cm -2 . Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10% of the initial doping concentration for [O i ]=9x10 17 cm -3 , while for normal detector grade material with [O i ] below 5x10 16 cm -3 that value is 60-90%. Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentration with an averaged introduction rate of (1.49±0.03)x10 -2 cm -1 . Only one material was found exhibiting a significantly smaller value of about 0.6x10 -2 cm -1 and thus indicating the possibility to suppress the radiation-induced acceptor creation by material modification. Finally, we show that the experimental findings disagree in several important aspects with predictions made by microscopic defect kinetics models, leaving the physical background of some of the measured data as an open question

  11. Application of MOSFET radiation detector for patient dosimetry

    International Nuclear Information System (INIS)

    Soubra, M.; Cygler, J.; Szanto, J.

    1996-01-01

    Purpose: A new direct reading Metal Oxide-Silicon Field Effect Transistor (MOSFET) based radiation detector system has been investigated in a variety of clinical radiotherapy procedures. The aim of this study is to report on the clinical applicability of such a device, its ease of use and on its dosimetric properties that include precision angular and energy dependence. Comparisons of patient dose measurements obtained by the MOSFET based system and the commonly used thermoluminescence dosimeters (TLD) and diodes are discussed. Material and Methods: A commercially available MOSFET dosimetry system that employs dual MOSFET dual bias arrangements has been used in this study. The detector is bonded with the epoxy to the end of a long (1.5 m) flexible cable whose other end is connected to a bias supply box operated by a battery. The bias box can accommodate up to 5 MOSFETs and after radiation exposure the dose can be determined by connecting the detectors to a pre calibrated reader. For the clinical evaluation 5 MOSFETs were used on patients undergoing total body irradiation (TBI) and high dose rate brachytherapy (HDR). The MOSFET detectors were taped to patient surface adjacent to the routinely used TLDs and/or diodes. To examine energy dependence the MOSFET sensitivity (mV/Gy) was determined in relation to a calibrated dose from 6 and 18 MV photon beams. The directional dependence was investigated by placing a MOSFET during irradiation in a special polystyrene insert that can be manually rotated to the required angle. Precision (reproducibility) measurements were made by exposing MOSFETs to multiple fractions of dose in the range of 3 x 10 -2 to 2 Gy. Results: In 3 of TBI trials the diodes measured average dose was within 1.0% of the prescribed dose compared to 3.7% for TLDs and 1.8% for MOSFETs. The MOSFETs average sensitivity for 6 MV was within 2% of the 18 MV photon beam. The reproducibility of MOSFET response was better than 3 % provided the dose per fraction is

  12. Test study of boron nitride as a new detector material for dosimetry in high-energy photon beams

    Science.gov (United States)

    Poppinga, D.; Halbur, J.; Lemmer, S.; Delfs, B.; Harder, D.; Looe, H. K.; Poppe, B.

    2017-09-01

    The aim of this test study is to check whether boron nitride (BN) might be applied as a detector material in high-energy photon-beam dosimetry. Boron nitride exists in various crystalline forms. Hexagonal boron nitride (h-BN) possesses high mobility of the electrons and holes as well as a high volume resistivity, so that ionizing radiation in the clinical range of the dose rate can be expected to produce a measurable electrical current at low background current. Due to the low atomic numbers of its constituents, its density (2.0 g cm-3) similar to silicon and its commercial availability, h-BN appears as possibly suitable for the dosimetry of ionizing radiation. Five h-BN plates were contacted to triaxial cables, and the detector current was measured in a solid-state ionization chamber circuit at an applied voltage of 50 V. Basic dosimetric properties such as formation by pre-irradiation, sensitivity, reproducibility, linearity and temporal resolution were measured with 6 MV photon irradiation. Depth dose curves at quadratic field sizes of 10 cm and 40 cm were measured and compared to ionization chamber measurements. After a pre-irradiation with 6 Gy, the devices show a stable current signal at a given dose rate. The current-voltage characteristic up to 400 V shows an increase in the collection efficiency with the voltage. The time-resolved detector current behavior during beam interrupts is comparable to diamond material, and the background current is negligible. The measured percentage depth dose curves at 10 cm  ×  10 cm field size agreed with the results of ionization chamber measurements within  ±2%. This is a first study of boron nitride as a detector material for high-energy photon radiation. By current measurements on solid ionization chambers made from boron nitride chips we could demonstrate that boron nitride is in principle suitable as a detector material for high-energy photon-beam dosimetry.

  13. Responses of conventional and extended-range neutron detectors in mixed radiation fields around a 150-MeV electron LINAC

    International Nuclear Information System (INIS)

    Lin, Yu-Chi; Sheu, Rong-Jiun; Chen, Ang-Yu

    2015-01-01

    This study analyzed the responses of two types of neutron detector in mixed gamma-ray and neutron radiation fields around a 150-MeV electron linear accelerator (LINAC). The detectors were self-assembled, high efficiency, and designed in two configurations: (1) a conventional moderated-type neutron detector based on a large cylindrical He-3 proportional counter; and (2) an extended-range version with an embedded layer of lead in the moderator to increase the detector’s sensitivity to high-energy neutrons. Two sets of the detectors were used to measure neutrons at the downstream and lateral locations simultaneously, where the radiation fields differed considerably in intensities and spectra of gamma rays and neutrons. Analyzing the detector responses through a comparison between calculations and measurements indicated that not only neutrons but also high-energy gamma rays (>5 MeV) triggered the detectors because of photoneutrons produced in the detector materials. In the lateral direction, the contribution of photoneutrons to both detectors was negligible. Downstream of the LINAC, where high-energy photons were abundant, photoneutrons contributed approximately 6% of the response of the conventional neutron detector; however, almost 50% of the registered counts of the extended-range neutron detector were from photoneutrons because of the presence of the detector rather than the effect of the neutron field. Dose readings delivered by extended-range neutron detectors should be interpreted cautiously when used in radiation fields containing a mixture of neutrons and high-energy gamma rays

  14. Radiation Hazard Detector

    Science.gov (United States)

    1978-01-01

    NASA technology has made commercially available a new, inexpensive, conveniently-carried device for protection, of people exposed to potentially dangerous levels of microwave radiation. Microwaves are radio emissions of extremely high frequency. They can be hazardous but the degree of hazard is not yet well understood. Generally, it is believed that low intensity radiation of short duration is not harmful but that exposure to high levels can induce deep internal burns, affecting the circulatory and nervous systems, and particularly the eyes. The Department of Labor's Occupational Safety and Health Administration (OSHA) has established an allowable safe threshold of exposure. However, people working near high intensity sources of microwave energy-for example, radar antennas and television transmitters-may be unknowingly exposed to radiation levels beyond the safe limit. This poses not only a personal safety problem but also a problem for employers in terms of productivity loss, workman's compensation claims and possible liability litigation. Earlier-developed monitoring devices which warn personnel of dangerous radiation levels have their shortcomings. They can be cumbersome and awkward to use while working. They also require continual visual monitoring to determine if a person is in a dangerous area of radiation, and they are relatively expensive, another deterrent to their widespread adoption. In response to the need for a cheaper and more effective warning system, Jet Propulsion Laboratory developed, under NASA auspices, a new, battery-powered Microwave Radiation Hazard Detector. To bring the product to the commercial market, California Institute Research Foundation, the patent holder, granted an exclusive license to Cicoil Corporation, Chatsworth, California, an electronic components manufacturer.

  15. Method and apparatus for logging a borehole employing dual radiation detectors

    International Nuclear Information System (INIS)

    Arnold, D.M.

    1986-01-01

    An apparatus is described for logging a characteristic of a borehole in an earth formation employing nuclear count rate data selectively compensated for non-standard borehole conditions, comprising: a sonde, movable in a borehole, having: a radiation source for emitting radiation into earth formations adjacent the wellbore; first detector, spaced longitudinally from the radiation source, for detecting radiation scattered back to the detector and generating a first signal representative of a first count rate value, C/sub SS/; and second detector spaced a different longitudinal distance from the radiation source, for detecting radiation scattered back to the detector and generating a second signal representative of a count rate value, C/sub LS/; memory means for storing a predetermined threshold value, first predetermined relationships between the borehole characteristic and count rate values C/sub LS/, C/sub SS/; and second predetermined relationships between the borehole characteristic and ratios of C/sub LS/ to C/sub SS/; electronic means for producing a signal related in value to the borehole characteristic, which electronic means compares at least one of the first and second count rate value signals with the predetermined threshold value; means for recording the signal generated by the electronic means

  16. Calculation of the relative efficiency of thermoluminescent detectors to space radiation

    International Nuclear Information System (INIS)

    Bilski, P.

    2011-01-01

    Thermoluminescent (TL) detectors are often used for measurements of radiation doses in space. While space radiation is composed of a mixture of heavy charged particles, the relative TL efficiency depends on ionization density. The question therefore arises: what is the relative efficiency of TLDs to the radiation present in space? In the attempt to answer this question, the relative TL efficiency of two types of lithium fluoride detectors for space radiation has been calculated, based on the theoretical space spectra and the experimental values of TL efficiency to ion beams. The TL efficiency of LiF:Mg,Ti detectors for radiation encountered at typical low-Earth’s orbit was found to be close to unity, justifying a common application of these TLDs to space dosimetry. The TL efficiency of LiF:Mg,Cu,P detectors is significantly lower. It was found that a shielding may have a significant influence on the relative response of TLDs, due to changes caused in the radiation spectrum. In case of application of TLDs outside the Earth’s magnetosphere, one should expect lower relative efficiency than at the low-Earth’s orbit.

  17. Development of (Cd,Zn)Te X-ray and gamma ray radiation detectors for medical and security applications

    International Nuclear Information System (INIS)

    Franc, J.; Hoeschl, P.; Belas, E.; Grill, V.; Fauler, A.; Dambacher, M.; Procz, S.

    2011-01-01

    Full text: There is a growing need for large area X-and Gamma radiation detectors for penetrating radiations in various fields of application e.g. astronomy, detectors for nuclear medicine, biosensor materials, security, non-proliferation of hazardous materials, and environmental applications etc. Direct X-rays conversion into electric charges in a semiconductor is envisaged with better spectroscopic characteristics to improve contrast and quantitative measurements compared to indirect detection using scintillators. The family of II-VI semiconductor materials combine a range of excellent properties such as their high sensitivity due to the high mobility-lifetime products, their high energy resolution as a consequence of the electron-hole pair formation energy, their reasonable maturity in terms of microelectronic technologies required for commercial detector fabrication, wide range of stopping power and band-gaps available. In particular, CdTe and Cd x Zn 1-x Te (CZT) with Zn=0.1 offer a favorable combination of physical and chemical properties that makes it attractive as a room temperature X-ray detector material of choice for many applications involving photon energies up to several hundreds of keV. From the scientific experience accumulated in the past years, the detector properties are strongly dependent on a series of parameters which must be strictly controlled during crystal growth, such as the homogeneity, stoichiometry and the related intrinsic defects which appear during the material growth, a high mobility-lifetime for electron and holes is mandatory etc. Production of detector-grade CdTe and CdZnTe on industrial scale is still a challenge and optimal growth methods and growth conditions have been under intensive investigation. Progress in crystal growth and characterization achieved in a project of Institute partnership between Charles University in Prague and University of Freiburg, Germany which was sponsored by Alexander von Humboldt Foundation, will

  18. [Effects of ionizing radiation on scintillators and other particle detectors

    International Nuclear Information System (INIS)

    Proudfoot, J.

    1992-01-01

    It is my task to summarise the great variety of topics (covering a refreshing mix of physics, chemistry and technology) presented at this conference, which has focused on the effects of ionising radiation on scintillators and other particle detectors. One of the reasons and the central interest of many of the participants was the use of such detectors in experiments at two future large hadron colliders: the Superconducting Super Collider to be operating outside of Dallas in the United States by the turn of the decade and its European counterpart the Large Hadron Collider to be operating outside of Geneva in Switzerland on a similar time scale. These accelerators are the ''apple of the high energy physicist's eye.'' Their goal is to uncover the elusive Higgs particle and thereby set the cornerstone in our current knowledge of elementary particle interactions. This is the Quest, and from this lofty height the presentations rapidly moved on to the specific questions of experimental science: how such an experiment is carried out; why radiation damage is an issue; how radiation damage affects detectors; which factors affect radiation damage characteristics; which factors are not affected by radiation damage; and how better detectors may be constructed. These were the substance of this conference

  19. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Nachman, Benjamin Philip; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of $10^{15}$ 1 MeV $n_\\mathrm{eq}/\\mathrm{cm}^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This talk presents a digitization model that includes radiation damage effects to the ATLAS Pixel sensors for the first time. After a thorough description of the setup, predictions for basic Pixel cluster properties are presented alongside first validation studies with Run 2 collision data.

  20. Radiation detector

    International Nuclear Information System (INIS)

    Conrad, B.; Finkenzeller, J.; Kiiehn, G.; Lichtenberg, W.

    1984-01-01

    In an exemplary embodiment, a flat radiation beam is detected having a common electrode disposed parallel to the beam plane at one side and a common support with a series of individual conductors providing electrodes opposite successive portions of the common electrode and lying in a plane also parallel to the beam plane. The beam may be fan-shaped and the individual electrodes may be aligned with respective ray paths separated by uniform angular increments in the beam plane. The individual conductors and the connection thereof to the exterior of the detector housing may be formed on an insulator which can be folded into a T-shape for leading the supply conductors for alternate individual conductors toward terminals at opposite sides of the chamber

  1. Alpha particle response study of polycrstalline diamond radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Amit; Topkar, Anita [Electronics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085 (India)

    2016-05-23

    Chemical vapor deposition has opened the possibility to grow high purity synthetic diamond at relatively low cost. This has opened up uses of diamond based detectors for wide range of applications. These detectors are most suitable for harsh environments where standard semiconductor detectors cannot work. In this paper, we present the fabrication details and performance study of polycrystalline diamond based radiation detector. Effect of different operating parameters such as bias voltage and shaping time for charge collection on the performance of detector has been studied.

  2. Silicon-lithium nuclear radiation detectors. Kremnii-litievye detektory yadernogo izlucheniya

    Energy Technology Data Exchange (ETDEWEB)

    Azimov, S.A.; Muminov, R.A.; Shamirzaev, S.Kh.; Yafasov, A.Ya.

    1981-01-01

    A presentation is made of the physical principles underlying the design, building, and technology of silicon-lithium detectors and ways of improving them. Criteria of nuclear radiation control and selection and the connection between radiation and detector properties are discussed. A study is made of the effect that various defects have on the process of charge collection and formation of amplitude spectra during the recording of various types of particles. A detailed examination is made of the optimal technological systems for making detectors with high energy and time resolutions, and features of producing high-quality detectors which employ the use of ion-laser and other methods of modern semiconductor technology. 322 references, 102 figures, 2 tables.

  3. Transition radiation detectors for electron identification beyond 1 GeV/c

    International Nuclear Information System (INIS)

    Appuhn, R.D.; Heinloth, K.; Lange, E.; Oedingen, R.; Schloesser, A.

    1987-07-01

    Transition radiation detectors (TRDs) have been tested for the separation of electrons from pions in the momentum range between 1 GeV/c and 6 GeV/c. Foams as well as fibres and foils served as radiator materials while two types of chambers, a longitudinal drift chamber (DC) and a multiwire proportional chamber (MWPC), both of 16 mm depth and dominantly filled with xenon, were used for detecting the transition radiation photons with a setup of four chambers. Analyzing the data we compared the methods of mean, truncated mean and of maximum likelihood of the total charge measurements and several methods of cluster analysis. As a result of the total charge measurements performed at test beams at CERN and DESY we obtained about 1% pion contamination at 90% electron efficiency for the polypropylene materials in the configuration of four modules with a total length of 40 cm. An improvement by a factor of about two for the electron/pion discrimination can be obtained in case of a detailed analysis of the clusters. (orig.)

  4. Characterization and calibration of radiation-damaged double-sided silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, L. [Institut für Kernphysik, Universität zu Köln, D-50937 Köln (Germany); Vogt, A., E-mail: andreas.vogt@ikp.uni-koeln.de [Institut für Kernphysik, Universität zu Köln, D-50937 Köln (Germany); Reiter, P.; Birkenbach, B.; Hirsch, R.; Arnswald, K.; Hess, H.; Seidlitz, M.; Steinbach, T.; Warr, N.; Wolf, K. [Institut für Kernphysik, Universität zu Köln, D-50937 Köln (Germany); Stahl, C.; Pietralla, N. [Institut für Kernphysik, Technische Universität Darmstadt, D-64291 Darmstadt (Germany); Limböck, T.; Meerholz, K. [Physikalische Chemie, Universität zu Köln, D-50939 Köln (Germany); Lutter, R. [Maier-Leibnitz-Laboratorium, Ludwig-Maximilians-Universität München, D-85748 Garching (Germany)

    2017-05-21

    Double-sided silicon strip detectors (DSSSD) are commonly used for event-by-event identification of charged particles as well as the reconstruction of particle trajectories in nuclear physics experiments with stable and radioactive beams. Intersecting areas of both p- and n-doped front- and back-side segments form individual virtual pixel segments allowing for a high detector granularity. DSSSDs are employed in demanding experimental environments and have to withstand high count rates of impinging nuclei. The illumination of the detector is often not homogeneous. Consequently, radiation damage of the detector is distributed non-uniformly. Position-dependent incomplete charge collection due to radiation damage limits the performance and lifetime of the detectors, the response of different channels may vary drastically. Position-resolved charge-collection losses between front- and back-side segments are investigated in an in-beam experiment and by performing radioactive source measurements. A novel position-resolved calibration method based on mutual consistency of p-side and n-side charges yields a significant enhancement of the energy resolution and the performance of radiation-damaged parts of the detector.

  5. Search for Physics beyond the Standard Model with the ATLAS detector and the development of radiation detectors

    CERN Document Server

    Silver, Yiftah

    We are investigating a radiation detector based on plasma display panel technology, the principal component of plasma television displays. This Plasma Panel Sensor (PPS) technology is a variant of micro-pattern gas radiation detectors. Based on the properties of existing plasma display panels, we expect eventually to be able to build a sealed array of plasma discharge gas cells to detect ionizing radiation with fast rise time of less than 10ns and high spatial resolution using a pixel pitch of less than 100 micrometer. In this thesis I shall describe our program of testing plasma display panels as detectors, including simulations, design and the first laboratory and beam studies that demonstrate the detection of cosmic ray muons, beta rays and medium energy protons. The ATLAS detector is used to search for high-mass resonances, in particular heavy neutral gauge bosons (Z') and excited states of Kaluza-Klein γ/Z bosons decaying to an electron-positron pair or a muon-antimuon pair. Results are presented based ...

  6. Radiation-hard Active Pixel Sensors for HL-LHC Detector Upgrades based on HV-CMOS Technology

    CERN Document Server

    Miucci, A; Hemperek, T.; Hügging, F.; Krüger, H.; Obermann, T.; Wermes, N.; Garcia-Sciveres, M.; Backhaus, M.; Capeans, M.; Feigl, S.; Nessi, M.; Pernegger, H.; Ristic, B.; Gonzalez-Sevilla, S.; Ferrere, D.; Iacobucci, G.; Rosa, A.La; Muenstermann, D.; George, M.; Grosse-Knetter, J.; Quadt, A.; Rieger, J.; Weingarten, J.; Bates, R.; Blue, A.; Buttar, C.; Hynds, D.; Kreidl, C.; Peric, I.; Breugnon, P.; Pangaud, P.; Godiot-Basolo, S.; Fougeron, D.; Bompard, F.; Clemens, J.C.; Liu, J; Barbero, M.; Rozanov, A

    2014-01-01

    Luminosity upgrades are discussed for the LHC (HL-LHC) which would make updates to the detectors necessary, requiring in particular new, even more radiation-hard and granular, sensors for the inner detector region. 1Corresponding author. c CERN 2014, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl. Any further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation and DOI. doi:10.1088/1748-0221/9/05/C050642014 JINST 9 C05064 A proposal for the next generation of inner detectors is based on HV-CMOS: a new family of silicon sensors based on commercial high-voltage CMOS technology, which enables the fabrication of part of the pixel electronics inside the silicon substrate itself. The main advantages of this technology with respect to the standard silicon sensor technology are: low material budget, fast charge collection time, high radiation tolerance, low cost and operation a...

  7. New detectors of neutron, gamma- and X-radiations

    CERN Document Server

    Lobanov, N S

    2002-01-01

    Paper presents new detectors to record absorbed doses of neutron, gamma- and X-ray radiations within 0-1500 Mrad range. DBF dosimeter is based on dibutyl phthalate. EDS dosimeter is based on epoxy (epoxide) resin, while SD 5-40 detector is based on a mixture of dibutyl phthalate and epoxy resin. Paper describes experimental techniques to calibrate and interprets the measurement results of absorbed doses for all detectors. All three detectors cover 0-30000 Mrad measured does range. The accuracy of measurements is +- 10% independent (practically) of irradiation dose rates within 20-2000 rad/s limits under 20-80 deg C temperature

  8. Graphene Field Effect Transistor-Based Detectors for Detection of Ionizing Radiation

    International Nuclear Information System (INIS)

    Jovanovic, Igor; Cazalas, Edward; Childres, I.; Patil, A.; Koybasi, O.; Chen, Y-P.

    2013-06-01

    We present the results of our recent efforts to develop novel ionizing radiation sensors based on the nano-material graphene. Graphene used in the field effect transistor architecture could be employed to detect the radiation-induced charge carriers produced in undoped semiconductor absorber substrates, even without the need for charge collection. The detection principle is based on the high sensitivity of graphene to ionization-induced local electric field perturbations in the electrically biased substrate. We experimentally demonstrated promising performance of graphene field effect transistors for detection of visible light, X-rays, gamma-rays, and alpha particles. We propose improved detector architectures which could result in a significant improvement of speed necessary for pulsed mode operation. (authors)

  9. Monitoring the Radiation Damage of the ATLAS Pixel Detector

    CERN Document Server

    Cooke, M; The ATLAS collaboration

    2012-01-01

    The Pixel Detector is the innermost charged particle tracking component employed by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The instantaneous luminosity delivered by the LHC, now routinely in excess of 5x10^{33} cm^{-2} s^{-1}, results in a rapidly increasing accumulated radiation dose to the detector. Methods based on the sensor depletion properties and leakage current are used to monitor the evolution of the radiation damage, and results from the 2011 run are presented.

  10. Monitoring the radiation damage of the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Cooke, M.

    2013-01-01

    The pixel detector is the innermost charged particle tracking component employed by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The instantaneous luminosity delivered by the LHC, now routinely in excess of 5×10 33 cm −2 s −1 , results in a rapidly increasing accumulated radiation dose to the detector. Methods based on the sensor depletion properties and leakage current are used to monitor the evolution of the radiation damage, and results from the 2011 run are presented

  11. Radiation portal monitor with {sup 10}B+ZnS(Ag) neutron detector performance for the detection of special nuclear materials

    Energy Technology Data Exchange (ETDEWEB)

    Guzman G, K. A.; Gallego, E.; Lorente, A.; Ibanez F, S. [Universidad Politecnica de Madrid, Departamento de Ingenieria Energetica, ETSI Industriales, C. Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico); Gonzalez, J. A. [Universidad Politecnica de Madrid, Laboratorio de Ingenieria Nuclear, ETSI Caminos, Canales y Puertos, C. Prof. Aranguren 3, 28040 Madrid (Spain); Mendez, R., E-mail: ingkarenguzman@gmail.com [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Laboratorio de Patrones Neutronicos, Av. Complutense 40, 28040 Madrid (Spain)

    2016-10-15

    In homeland security, neutron detection is used to prevent the smuggling of special nuclear materials. Thermal neutrons are normally detected with {sup 3}He proportional counters, in the radiation portal monitors, Rpms, however due to the {sup 3}He shortage new procedures are being studied. In this work Monte Carlo methods, using the MCNP6 code, have been used to study the neutron detection features of a {sup 10}B+ZnS(Ag) under real conditions inside of a Rpm. The performance for neutron detection was carried out for {sup 252}Cf, {sup 238}U and {sup 239}Pu under different conditions. In order to mimic an actual situation occurring at border areas, a sample of SNM sited inside a vehicle was simulated and the Rpm with {sup 10}B+ZnS(Ag) response was calculated. At 200 cm the {sup 10}B+ZnS(Ag) on Rpm response is close to 2.5 cps-ng {sup 252}Cf, when the {sup 252}Cf neutron source is shielded with 0.5 cm-thick lead and 2.5 cm-thick polyethylene fulfilling the ANSI recommendations. Three different geometries of neutron detectors of {sup 10}B+ZnS(Ag) in a neutron detection system in Rpm were modeled. Therefore, the {sup 10}B+ZnS(Ag) detectors are an innovative and viable replacement for the {sup 3}He detectors in the Rpm. (Author)

  12. Radiation meter

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, P H

    1990-05-30

    Measuring means comprising first and second silicon PIN diode detectors both being covered with a thin layer of conducting material and the second detector being additionally covered with a relatively thick layer of material, the thickness being chosen such that beta radiation dose rate can be measured in beta radiation fields of high or medium energy, and in the presence of X and gamma radiation. (author). 2 figs.

  13. Radiation Damage Modeling for 3D Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Wallangen, Veronica; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  14. Field oxide radiation damage measurements in silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, M [Particle Detector Group, Fermilab, Batavia, IL (United States) Research Inst. for High Energy Physics (SEFT), Helsinki (Finland); Singh, P; Shepard, P F [Dept. of Physics and Astronomy, Univ. Pittsburgh, PA (United States)

    1993-04-01

    Surface radiation damage in planar processed silicon detectors is caused by radiation generated holes being trapped in the silicon dioxide layers on the detector wafer. We have studied charge trapping in thick (field) oxide layers on detector wafers by irradiating FOXFET biased strip detectors and MOS test capacitors. Special emphasis was put on studying how a negative bias voltage across the oxide during irradiation affects hole trapping. In addition to FOXFET biased detectors, negatively biased field oxide layers may exist on the n-side of double-sided strip detectors with field plate based n-strip separation. The results indicate that charge trapping occurred both close to the Si-SiO[sub 2] interface and in the bulk of the oxide. The charge trapped in the bulk was found to modify the electric field in the oxide in a way that leads to saturation in the amount of charge trapped in the bulk when the flatband/threshold voltage shift equals the voltage applied over the oxide during irradiation. After irradiation only charge trapped close to the interface is annealed by electrons tunneling to the oxide from the n-type bulk. (orig.).

  15. Monte Carlo simulation of radiation streaming from a radioactive material shipping cask

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Schwarz, R.A.; Tang, J.S.

    1996-01-01

    Simulated detection of gamma radiation streaming from a radioactive material shipping cask have been performed with the Monte Carlo codes MCNP4A and MORSE-SGC/S. Despite inherent difficulties in simulating deep penetration of radiation and streaming, the simulations have yielded results that agree within one order of magnitude with the radiation survey data, with reasonable statistics. These simulations have also provided insight into modeling radiation detection, notably on location and orientation of the radiation detector with respect to photon streaming paths, and on techniques used to reduce variance in the Monte Carlo calculations. 13 refs., 4 figs., 2 tabs

  16. Active microphonic noise cancellation in radiation detectors

    International Nuclear Information System (INIS)

    Zimmermann, Sergio

    2013-01-01

    A new adaptive filtering technique to reduce microphonic noise in radiation detectors is presented. The technique is based on system identification that actively cancels the microphonic noise. A sensor is used to measures mechanical disturbances that cause vibration on the detector assembly, and the digital adaptive filtering estimates the impact of these disturbances on the microphonic noise. The noise then can be subtracted from the actual detector measurement. In this paper the technique is presented and simulations are used to support this approach. -- Highlights: •A sensor is used to measures mechanical disturbances that cause vibration on the detector assembly. •Digital adaptive filtering estimates the impact of these disturbances on the microphonic noise. •The noise is then subtracted from the actual detector measurement. •We use simulations to demonstrate the performance of this approach. •After cancellation, we recover most of the original energy resolution

  17. Study of gel materials as radioactive 222Rn gas detectors

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J. I.; Rickards, J.; Gammage, R. B.

    2006-01-01

    Commercial hair gel material (polyvinyl pyrolidone triethanolamine carbo-pol in water) and bacteriological agar (phycocolloid extracted from a group of red-purple algae, usually Gelidium sp.) have been studied as radioactive radon gas detectors. The detection method is based on the diffusion of the radioactive gas in the gel material, and the subsequent measurement of trapped products of the natural decay of radon by gamma spectrometry. From the several radon daughters with gamma radiation emission ( 214 Pb, 214 Bi, 214 Po, 210 Pb, 210 Po), two elements, 214 Pb (0.352 MeV) and 214 Bi (0.609 MeV), were chosen for the analysis in this work; in order to determine the best sensitivity, corrections were made for the short half-life of the analysed isotopes. For the gamma spectrometry analysis, a hyper-pure germanium solid state detector was used, associated with a PC multichannel analyser card with Maestro R and Microsoft R Excel R software. The results show the viability of the method: a linear response in a wide radon concentration range (450-10,000 Bq m -3 ), reproducibility of data, easy handling and low cost of the gel material. This detection methodology opens new possibilities for measurements of radon and other radioactive gases. (authors)

  18. Liquid ionizing radiaion detector

    International Nuclear Information System (INIS)

    deGaston, A.N.

    1979-01-01

    A normally nonconducting liquid such as liquid hydrocarbon is encased between a pair of electrodes in an enclosure so that when the liquid is subjected to ionizing radiation, the ion pairs so created measurably increase the conductivity of the fluid. The reduced impedance between the electrodes is detectable with a sensitive ohm-meter and indicates the amount of ionizing radiation. The enclosure, the electrodes and the fluid can be constructed of materials that make the response of the detector suitable for calibrating a large range of radiation energy levels. The detector is especially useful in medical applications where tissue equivalent X ray detectors are desired

  19. The AMS-02 transition radiation detector

    CERN Document Server

    Kirn, Th

    2004-01-01

    The Alpha Magnetic Spectrometer AMS02 will be equipped with a large transition radiation detector (TRD) to achieve a proton background suppression necessary for dark matter searches. The AMS02 TRD consists of 20 layers of fleece radiator each with Xe/CO//2 proportional wire straw tubes read out by a dedicated low-power data- acquisition system. A space-qualified TRD design will be presented. The performance of a 20-layer prototype was tested at CERN with electron, myon and pion beams up to l00 GeV and with protons up to 250 GeV. The beam-test results will be compared to Geant3 MC predictions. The detector is under construction at RWTH Aachen; the gas system will be built at MIT, slow-control at MIT and INFN Rome and DAQ at TH Karlsruhe. This project is funded by the German Space Agency DLR, the US Department of Energy DOE and NASA.

  20. Electromechanically cooled germanium radiation detector system

    International Nuclear Information System (INIS)

    Lavietes, Anthony D.; Joseph Mauger, G.; Anderson, Eric H.

    1999-01-01

    We have successfully developed and fielded an electromechanically cooled germanium radiation detector (EMC-HPGe) at Lawrence Livermore National Laboratory (LLNL). This detector system was designed to provide optimum energy resolution, long lifetime, and extremely reliable operation for unattended and portable applications. For most analytical applications, high purity germanium (HPGe) detectors are the standard detectors of choice, providing an unsurpassed combination of high energy resolution performance and exceptional detection efficiency. Logistical difficulties associated with providing the required liquid nitrogen (LN) for cooling is the primary reason that these systems are found mainly in laboratories. The EMC-HPGe detector system described in this paper successfully provides HPGe detector performance in a portable instrument that allows for isotopic analysis in the field. It incorporates a unique active vibration control system that allows the use of a Sunpower Stirling cycle cryocooler unit without significant spectral degradation from microphonics. All standard isotopic analysis codes, including MGA and MGA++, GAMANL, GRPANL and MGAU, typically used with HPGe detectors can be used with this system with excellent results. Several national and international Safeguards organisations including the International Atomic Energy Agency (IAEA) and U.S. Department of Energy (DOE) have expressed interest in this system. The detector was combined with custom software and demonstrated as a rapid Field Radiometric Identification System (FRIS) for the U.S. Customs Service . The European Communities' Safeguards Directorate (EURATOM) is field-testing the first Safeguards prototype in their applications. The EMC-HPGe detector system design, recent applications, and results will be highlighted

  1. A radiation detector fabricated from silicon photodiode.

    Science.gov (United States)

    Yamamoto, H; Hatakeyama, S; Norimura, T; Tsuchiya, T

    1984-12-01

    A silicon photodiode is converted to a low energy charged particle radiation detector. The window thickness of the fabricated detector is evaluated to be 50 micrograms/cm2. The area of the depletion region is 13.2 mm2 and the depth of it is estimated to be about 100 microns. The energy resolution (FWHM) is 14.5 ke V for alpha-particles from 241Am and 2.5 ke V for conversion electrons from 109Cd, respectively.

  2. The use of detectors based on ionisation recombination in radiation protection

    International Nuclear Information System (INIS)

    Sullivan, A.H.

    1984-01-01

    Intitial recombination of ionisation in a gas depends on the ionisation density and hence on the linear energy transfer along the tracks of charged particles. This effect can be used as a basis for instruments that respond to different types of ionising radiation approximately in the way required by the quality factor-linear energy transfer relation recommended by the ICRP for use in radiation protection. Empirical instruments based on ionisation recombination that have been used for radiation protection measurements are reviewed, and relations are derived from recombination theory that show that the response of such detectors can be readily predicted. The usefulness of recombination instruments in radiation protection is discussed and their advantages and limitations assessed. It is shown that their main application will be as reference instruments against which other detectors can be calibrated. As an extension to using recombination detectors as reference instruments, the feasibility of specifying radiation quality in terms of ionisation recombination is investigated. (author)

  3. Gamma-ray detector based on high pressure xenon for radiation and environmental safety

    International Nuclear Information System (INIS)

    Kutny, V.E.; Rybka, A.V.; Davydov, L.N.; Pudov, A.O.; Sokolov, S.A.; Kholomeyev, G.A.; Melnikov, S.I.; Turchin, A.A.

    2017-01-01

    Gamma-spectrometers based on compressed xenon gas assigned for monitoring the reactors and the radiation background at nuclear power plants, non-proliferation of radioactive materials, supervision and control over the radiation background in the environmentally disadvantaged areas, and other applications, are very promising detectors with excellent performance characteristics. This article reports on the results of the first stage of work on the creation of the portable gamma-spectrometer based on compressed xenon that is unique for Ukraine. In order to work with ultra-pure gases under pressure, the complex cryogenic installation for Xe purification and detector filling was designed and manufactured. The installation was made of specially cleaned components, equipped with a heating system for the degassing of the inner walls, and is able of maintaining high vacuum down to 2 centre dot 10"-"9 mbar. A prototype ionization chamber for the use in portable HP Xe detectors was developed and made. For the detector testing, a spectrometric channel based on high-quality electronic components was designed and manufactured. In the initial experiments, a study of the properties of the purified Xe mixed with the dopant H_2 was carried out. The assessment of the lifetime of charge carriers τ in the working gas at a pressure of 30 bar gave the value of τ > 150 μs

  4. Characterization of a radiation detector for aircraft measurements

    International Nuclear Information System (INIS)

    Holanda M, L. de; Federico, C. A.; Caldas, L. V. E.

    2014-08-01

    Air crews, as pilots and flight attendants, are subjected to cosmic ray doses which can be higher than the average doses on workers from the nuclear industry. The diversity of particles of high energies present in the radiation field on board of air crafts turns the determination of the incident dose difficult, and requires special care regarding dosimetric systems to be used in this kind of radiation field. The Brazilian Air Force, through its Institute for Advanced Studies (Instituto de Estudos Avancados, IEAv/DCTA) in conjunction with the Institute of Energetic and Nuclear Research (Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP) are working on this subject since 2008. A prototype of a radiation detector for aircraft measurements was previously built and tested in flight and laboratory conditions. The detector is able of measuring a quantity known as absorbed dose (using passive dosimeters), which will subsequently be correlated to the ambient dose equivalent and the effective dose received by air crews. In this context, a theoretical approach through Monte Carlo simulations with the computational codes MCNP5 and MCNPX was used to model and characterize the detector response at such experimental conditions. This work presents the preliminary results of the computational modeling, with special emphasis on the comparison between the absorbed doses measured and simulated, and its relationship with the ambient dose equivalent and the effective dose for this detector. (author)

  5. Characterization of a radiation detector for aircraft measurements

    Energy Technology Data Exchange (ETDEWEB)

    Holanda M, L. de; Federico, C. A.; Caldas, L. V. E., E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares, Av. Lineu Prestes 2242, Cidade Universitaria, CEP 05508-000, Sao Paulo (Brazil)

    2014-08-15

    Air crews, as pilots and flight attendants, are subjected to cosmic ray doses which can be higher than the average doses on workers from the nuclear industry. The diversity of particles of high energies present in the radiation field on board of air crafts turns the determination of the incident dose difficult, and requires special care regarding dosimetric systems to be used in this kind of radiation field. The Brazilian Air Force, through its Institute for Advanced Studies (Instituto de Estudos Avancados, IEAv/DCTA) in conjunction with the Institute of Energetic and Nuclear Research (Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP) are working on this subject since 2008. A prototype of a radiation detector for aircraft measurements was previously built and tested in flight and laboratory conditions. The detector is able of measuring a quantity known as absorbed dose (using passive dosimeters), which will subsequently be correlated to the ambient dose equivalent and the effective dose received by air crews. In this context, a theoretical approach through Monte Carlo simulations with the computational codes MCNP5 and MCNPX was used to model and characterize the detector response at such experimental conditions. This work presents the preliminary results of the computational modeling, with special emphasis on the comparison between the absorbed doses measured and simulated, and its relationship with the ambient dose equivalent and the effective dose for this detector. (author)

  6. Studying radiative B decays with the Atlas detector

    International Nuclear Information System (INIS)

    Viret, S.

    2004-09-01

    This thesis is dedicated to the study of radiative B decays with the ATLAS detector at the LHC (large hadron collider). Radiative decays belong to the rare decays family. Rare decays transitions involve flavor changing neutral currents (for example b → sγ), which are forbidden at the lowest order in the Standard Model. Therefore these processes occur only at the next order, thus involving penguin or box diagrams, which are very sensitive to 'new physics' contributions. The main goal of our study is to show that it would be possible to develop an online selection strategy for radiative B decays with the ATLAS detector. To this end, we have studied the treatment of low energy photons by the ATLAS electromagnetic calorimeter (ECal). Our analysis shows that ATLAS ECal will be efficient with these particles. This property is extensively used in the next section, where a selection strategy for radiative B decays is proposed. Indeed, we look for a low energy region of interest in the ECal as soon as the level 1 of the trigger. Then, photon identification cuts are performed in this region at level 2. However, a large part of the proposed selection scheme is also based on the inner detector, particularly at level 2. The final results show that large amounts of signal events could be collected in only one year by ATLAS. A preliminary significance (S/√B) estimation is also presented. Encouraging results concerning the observability of exclusive radiative B decays are obtained. (author)

  7. Single-flux-quantum circuit technology for superconducting radiation detectors

    International Nuclear Information System (INIS)

    Fujimaki, Akira; Onogi, Masashi; Matsumoto, Tomohiro; Tanaka, Masamitsu; Sekiya, Akito; Hayakawa, Hisao; Yorozu, Shinichi; Terai, Hirotaka; Yoshikawa, Nobuyuki

    2003-01-01

    We discuss the application of the single-flux-quantum (SFQ) logic circuits to multi superconducting radiation detectors system. The SFQ-based analog-to-digital converters (ADCs) have the advantage in current sensitivity, which can reach less than 10 nA in a well-tuned ADC. We have also developed the design technology of the SFQ circuits. We demonstrate high-speed operation of large-scale integrated circuits such as a 2x2 cross/bar switch, arithmetic logic unit, indicating that our present SFQ technology is applicable to the multi radiation detectors system. (author)

  8. Study of material properties important for an optical property modulation-based radiation detection method for positron emission tomography

    OpenAIRE

    Tao, Li; Daghighian, Henry M.; Levin, Craig S.

    2017-01-01

    We compare the performance of two detector materials, cadmium telluride (CdTe) and bismuth silicon oxide (BSO), for optical property modulation-based radiation detection method for positron emission tomography (PET), which is a potential new direction to dramatically improve the annihilation photon pair coincidence time resolution. We have shown that the induced current flow in the detector crystal resulting from ionizing radiation determines the strength of optical modulation signal. A large...

  9. Self-powered neutron detector

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Todt, W.H.

    1976-01-01

    A self-powered neutron detector is detailed wherein a thin conductive layer of low neutron cross section, high density material is disposed about an emitter core of material which spontaneously emits radiation on neutron capture. The high density material is absorptive of beta radiation emitted by decay of the emitter core activation product, but is substantially transmissive to the high average energy prompt electrons emitted by the emitter core material. (author)

  10. Characterization of gaseous detectors at the CERN Gamma Irradiation Facility: GEM performance in presence of high background radiation

    CERN Document Server

    AUTHOR|(CDS)2097588

    Muon detection is an efficient tool to recognize interesting physics events over the high background rate expected at the Large Hadron Collider (LHC) at CERN. The muon systems of the LHC experiments are based on gaseous ionization detectors. In view of the High-Luminosity LHC (HL-LHC) upgrade program, the increasing of background radiation could affect the gaseous detector performance, especially decreasing the efficiency and shortening the lifetime through ageing processes. The effects of charge multiplication, materials and gas composition on the ageing of gaseous detectors have been studied for decades, but the future upgrade of LHC requires additional studies on this topic. At the CERN Gamma Irradiation Facility (GIF++), a radioactive source of cesium-137 with an activity of 14 TBq is used to reproduce reasonably well the expected background radiation at HL-LHC. A muon beam has been made available to study detector performance. The characterization of the beam trigger will be discussed in the present w...

  11. 175th International School of Physics "Enrico Fermi" : Radiation and Particle Detectors

    CERN Document Server

    Bottigli, U; Oliva, P

    2010-01-01

    High energy physics (HEP) has a crucial role in the context of fundamental physics. HEP experiments make use of a massive array of sophisticated detectors to analyze the particles produced in high-energy scattering events. This book contains the papers from the workshop 'Radiation and Particle Detectors', organized by the International School of Physics, and held in Varenna in July 2009. Its subject is the use of detectors for research in fundamental physics, astro-particle physics and applied physics. Subjects covered include the measurement of: the position and length of ionization trails, time of flight velocity, radius of curvature after bending the paths of charged particles with magnetic fields, coherent transition radiation, synchrotron radiation, electro-magnetic showers produced by calorimetric methods and nuclear cascades produced by hadrons in massive steel detectors using calorimetry. Detecting muons and the detection of Cherenkov radiation are also covered, as is the detection of neutrinos by ste...

  12. Review of the Radiation Environment in the Inner Detector

    CERN Document Server

    Dawson, I

    2000-01-01

    The radiation environment in the inner detector has been simulated using the particle transport program FLUKA with a recent description of the ATLAS experiment. Given in this note are particle fluences and doses at positions relevant to the PIXEL, SCT and TRT detectors. In addition, studies are reported on in which 1) information concerning the optimisation of the inner detector neutron-moderators is obtained and 2) the impact of including additional vacuum-equipment is assessed.

  13. Radiation portal monitor with "1"0B+ZnS(Ag) neutron detector performance for the detection of special nuclear materials

    International Nuclear Information System (INIS)

    Guzman G, K. A.; Gallego, E.; Lorente, A.; Ibanez F, S.; Vega C, H. R.; Gonzalez, J. A.; Mendez, R.

    2016-10-01

    In homeland security, neutron detection is used to prevent the smuggling of special nuclear materials. Thermal neutrons are normally detected with "3He proportional counters, in the radiation portal monitors, Rpms, however due to the "3He shortage new procedures are being studied. In this work Monte Carlo methods, using the MCNP6 code, have been used to study the neutron detection features of a "1"0B+ZnS(Ag) under real conditions inside of a Rpm. The performance for neutron detection was carried out for "2"5"2Cf, "2"3"8U and "2"3"9Pu under different conditions. In order to mimic an actual situation occurring at border areas, a sample of SNM sited inside a vehicle was simulated and the Rpm with "1"0B+ZnS(Ag) response was calculated. At 200 cm the "1"0B+ZnS(Ag) on Rpm response is close to 2.5 cps-ng "2"5"2Cf, when the "2"5"2Cf neutron source is shielded with 0.5 cm-thick lead and 2.5 cm-thick polyethylene fulfilling the ANSI recommendations. Three different geometries of neutron detectors of "1"0B+ZnS(Ag) in a neutron detection system in Rpm were modeled. Therefore, the "1"0B+ZnS(Ag) detectors are an innovative and viable replacement for the "3He detectors in the Rpm. (Author)

  14. Evaluation of the radiation field in the future circular collider detector

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00211473; Cerutti, Francesco; Ferrari, Alfredo; Riegler, Werner; Vlachoudis, Vasilis; CERN. Geneva. ATS Department

    2016-01-01

    The radiation load on a detector at a 100 TeV proton-proton collider, that is being investigated within the Future Circular Collider (FCC) study, is presented. A peak luminosity of 30 1034 cm−2s−1 and a total integrated luminosity of 30 ab−1 are assumed for these radiation studies. A first concept of the detector foresees the presence of central and forward sub-detectors that provide acceptance up to |η|=6 inside a magnetic field generated by the combination of a central solenoid and two forward dipoles. This layout has been modelled and relevant fluence and dose distributions have been calculated using the FLUKA Monte Carlo code. Distributions of fluence rates are discussed separately for charged particles, neutrons and pho- tons. Dose and 1 MeV neutron equivalent fluence, for the accumulated integrated luminosity, are presented. The peak values of these quantities in the different sub-detectors are highlighted, in order to define the radiation tolerance requirements for the choice of possible technol...

  15. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    Energy Technology Data Exchange (ETDEWEB)

    Scott Wilde, Raymond Keegan

    2008-07-01

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  16. Radiation hard detectors from silicon enriched with both oxygen and thermal donors improvements in donor removal and long-term stability with regard to neutron irradiation

    CERN Document Server

    Li, Z; Eremin, V; Dezillie, B; Chen, W; Bruzzi, M

    2002-01-01

    Detectors made on the silicon wafers with high concentration of thermal donors (TD), which were introduced during the high temperature long time (HTLT) oxygenation procedure, have been investigated in the study of radiation hardness with regard to neutron irradiation and donor removal problems in irradiated high resistivity Si detectors. Two facts have been established as the evidence of radiation hardness improvement of HTLT(TD) Si detectors irradiated below approx 10 sup 1 sup 4 n/cm sup 2 compared to detectors made on standard silicon wafers: the increase of space charge sign inversion fluence (of 1 MeV neutrons) due to lower initial Si resistivity dominated by TD, and the gain in the reverse annealing time constant tau favourable for this material. Coupled with extremely high radiation tolerance to protons observed earlier ('beta zero' behaviour in a wide range of fluence), detectors from HTLT(TD) Si may be unique for application in the experiments with multiple radiations. The changes in the effective sp...

  17. Modeling Radiation Damage Effects in 3D Pixel Digitization for the ATLAS Detector

    CERN Document Server

    Giugliarelli, Gilberto; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  18. Modeling Radiation Damage Effects in 3D Pixel Digitization for the ATLAS Detector

    CERN Document Server

    Wallangen, Veronica; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10$^{15}$ n$_\\mathrm{eq}$/cm$^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This work presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS detector.

  19. Detection and Imaging of High-Z Materials with a Muon Tomography Station Using GEM Detectors

    CERN Document Server

    Gnanvo, K; Bittner, W; Costa, F; Grasso, L; Hohlmann, M; Locke, J B; Martoiu, S; Muller, H; Staib, M; Tarazona, A; Toledo, J

    2010-01-01

    Muon tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons is a promising technique for detecting and imaging heavily shielded high-Z nuclear materials such as enriched uranium. This technique could complement standard radiation detection portals currently deployed at international borders and ports, which are not very sensitive to heavily shielded nuclear materials. We image small targets in 3D using $2\\times 2 \\times 2$ mm^3 voxels with a minimal muon tomography station prototype that tracks muons with Gas Electron Multiplier (GEM) detectors read out in 2D with x-y microstrips of 400 micron pitch. With preliminary electronics, the GEM detectors achieve a spatial resolution of 130 microns in both dimensions. With the next GEM-based prototype station we plan to probe an active volume of ~27 liters. We present first results on reading out all 1536 microstrips of a $30 \\times 30$ cm^2 GEM detector for the next muon tomography prototype with final frontend electronics and DAQ...

  20. Radiation-hard Active Pixel Sensors for HL-LHC Detector Upgrades based on HV-CMOS Technology

    International Nuclear Information System (INIS)

    Miucci, A; Gonzalez-Sevilla, S; Ferrere, D; Iacobucci, G; Rosa, A La; Muenstermann, D; Gonella, L; Hemperek, T; Hügging, F; Krüger, H; Obermann, T; Wermes, N; Garcia-Sciveres, M; Backhaus, M; Capeans, M; Feigl, S; Nessi, M; Pernegger, H; Ristic, B; George, M

    2014-01-01

    Luminosity upgrades are discussed for the LHC (HL-LHC) which would make updates to the detectors necessary, requiring in particular new, even more radiation-hard and granular, sensors for the inner detector region. A proposal for the next generation of inner detectors is based on HV-CMOS: a new family of silicon sensors based on commercial high-voltage CMOS technology, which enables the fabrication of part of the pixel electronics inside the silicon substrate itself. The main advantages of this technology with respect to the standard silicon sensor technology are: low material budget, fast charge collection time, high radiation tolerance, low cost and operation at room temperature. A traditional readout chip is still needed to receive and organize the data from the active sensor and to handle high-level functionality such as trigger management. HV-CMOS has been designed to be compatible with both pixel and strip readout. In this paper an overview of HV2FEI4, a HV-CMOS prototype in 180 nm AMS technology, will be given. Preliminary results after neutron and X-ray irradiation are shown

  1. Advances in the project about Pin type silicon radiation detectors

    International Nuclear Information System (INIS)

    Ramirez F, J.; Cerdeira, A.; Aceves, M.; Diaz, A.; Estrada, M.; Rosales, P.; Cabal, A.E.; Montano L, M.; Leyva, A.

    1998-01-01

    The obtained advances in the collaboration project ININ-CINVESTAV about development of Pin type semiconductor radiation detectors here are presented. It has been characterized the response to different types of radiation made in CINVESTAV and INAOE. Measurements have been realized with different types of sensitive to charge preamplifiers determining the main characteristics which must be executed to be able to be employed with low capacitance detectors. As applications it has been possible to measure the irradiation time in a mammography machine and X-ray energy spectra have been obtained in the order of 14 KeV, with 4 KeV at ambient temperature. The future actions of project have been indicated and the possible applications of these detectors. (Author)

  2. Technologies pioneered by LHC. Superconducting magnet and radiation-tolerant tracking detector

    International Nuclear Information System (INIS)

    Yamamoto, Akira; Unno, Yoshinobu

    2007-01-01

    In the LHC project of proton-proton collisions exploring the energy frontier, superconducting magnets and radiation-tolerant tracking detector play fundamental roles as key technologies. The superconducting magnets contribute to bending and focusing particle beam by using high magnetic field created with the NbTi superconductor cooled to the superfluid temperature of He (1.9 K). In order to overcome the unprecedented radiation damage and to capture the particles emerging with high energy and high density, the large area and highly radiation-tolerant silicon semiconductor tracking detector has been developed for the LHC experiment. (author)

  3. Radiation effects at the SSC

    Energy Technology Data Exchange (ETDEWEB)

    Gilchriese, M.G.D. [ed.] [Superconducting Super Collider Lab., Dallas, TX (United States)

    1988-06-01

    This report contains a preliminary study of the effects of the radiation levels expected at the SSC on potential detector components and a subset of materials to be used in the SSC accelerators. The report does not contain a discussion of radiation damage to electronics components that may be used at the SSC. We have investigated many of the effects of radiation on silicon detectors, on wire chambers, on scintillating materials and the associated readout, on optical fibers for data transmission and on structural or other materials to be used in detector or accelerator components. In the SSC accelerator complex, in particular the storage rings, radiation damage will not present significant problems different than those now faced by existing high energy accelerators. We find that the effects of radiation damage on SSC detector components will be significant at the design luminosity of the ssc and will limit, or determine, many of the options for different detector components. In this regard the reader should keep in mind that, in the absence of a specific detector design, it is not possible to form definitive conclusions regarding the viability of the detector components. Since the radiation levels in experiments at the SSC will depend on the geometry and composition of the apparatus, simple yes /no generalizations about the feasibility of a detector component are not possible.

  4. Scintillation Detectors for Charged Particles and Photons

    CERN Document Server

    Lecoq, P

    2011-01-01

    Scintillation Detectors for Charged Particles and Photons 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 '3.1.1 Scintillation Detectors for Charged Particles and Photons' of Section '3.1 Charged Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.1.1 Scintillation Detectors for Charged Particles and Photons 3.1.1.1 Basic detector principles and scintillator requirements 3.1.1.1.1 Interaction of ionizing radiation with scintillator material 3.1.1.1.2 Important scint...

  5. Test of radiation hardness of pcCVD detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schlemme, Steffen [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Technische Universitaet Darmstadt (Germany); Enders, Joachim [Technische Universitaet Darmstadt (Germany); Figuera, P.; Salamone, S. [LNS-INFN Catania (Italy); Fruehauf, J.; Kis, Mladen; Kratz, A.; Kurz, N.; Loechner, S.; Nociforo, Chiara; Schirru, Fabio; Szczepanczyk, B.; Traeger, M.; Visinka, R. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Musumarra, A. [LNS-INFN Catania (Italy); University of Catania (Italy)

    2016-07-01

    The new in-flight separator Super-FRS is under construction at the Facility for Antiproton and Ion Research (FAIR, Darmstadt). Ion rates up to 3 x 10{sup 11} {sup 238}U/spill demand an adaption of detectors to a high radiation environment. A test experiment to investigate the radiation hardness of polycrystalline diamond detectors (pcCVD) was performed at the LNS-INFN in Catania using a {sup 12}C beam at 62 MeV/u and intensities of up to 1.5 pnA. The setup consisted of pcCVD strip detectors to measure the beam profile, a single crystal diamond detector to calibrate the ionisation chamber working in current mode as a beam intensity monitor and a pcCVD sample to be irradiated. The IC used was designed for FAIR and showed a stable counting rate allowing us to calibrate and perform beam intensity measurements with it. The total measured counts on the sample were 8.25 x 10{sup 11} counts/mm{sup 2} over a period of 60 hours. Digital waveforms of the pcCVD signals were taken with an oscilloscope and analysed. The results showed no change of the pcCVD signal properties during the entire irradiation.

  6. Development of TiBr semiconductor crystal for applications as radiation detector and photodetector; Desenvolvimento do cristal semicondutor de brometo de talio para aplicacoes como detector de radiacao e fotodetector

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Icimone Braga de

    2006-07-01

    In this work, Tlbr crystals were grown by the Bridgman method from zone melted materials. The influence of the purification efficiency and the crystalline surface quality on the crystal were studied, evaluating its performance as a radiation detector. Due to significant improvement in the purification and crystals growth, good results have been obtained for the developed detectors. The spectrometric performance of the Tlbr detector was evaluated by {sup 241}Am (59 keV), {sup 133}Ba (80 e 355 keV), {sup 57}Co (122 keV), {sup 22}Na (511 keV) and {sup 137} Cs (662 keV) at room temperature. The best energy resolution results were obtained from purer detectors. Energy resolutions of 10 keV (16%), 12 keV (15%), 12 keV (10%), 28 keV (8%), 31 keV (6%) and 36 keV (5%) to 59, 80, 122, 355, 511 and 662 keV energies, respectively, were obtained. A study on the detection response at -20 deg C was also carried out, as well as the detector stability in function of the time. No significant difference was observed in the energy resolution between measurements at both temperatures. It was observed that the detector instability causes degradation of the spectroscopic characteristics during measurements at room temperature and the instability varies for each detector. This behavior was also verified by other authors. The viability to use the developed Tlbr crystal as a photodetector coupled to scintillators crystals was also studied in this work. Due to its quantum efficiency in the region from 350 to 500 nm, Tlbr shows to be a promising material to be used as a photodetector. As a possible application of this work, the development of a surgical probe has been initiated using the developed Tlbr crystal as the radiation detector of the probe. (author)

  7. The ALICE Transition Radiation Detector: construction, operation, and performance

    OpenAIRE

    Acharya, Shreyasi; Adam, Jaroslav; Ahmad, Nazeer; Bhattacharjee, Buddhadeb; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Umaka, Ejiro Naomi; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vala, Martin; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Bhom, Jihyun

    2018-01-01

    The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 G...

  8. Semiconductor scintillator detector for gamma radiation

    International Nuclear Information System (INIS)

    Laan, F.T.V. der; Borges, V.; Zabadal, J.R.S.

    2015-01-01

    Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and thermoluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD's (Electronic Personal Dosemeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were successfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm anthracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cumulative doses for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important features of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum. (author)

  9. Design and construction of the prototype synchrotron radiation detector

    CERN Document Server

    Anderhub, H; Baetzner, D; Baumgartner, S; Biland, A; Camps, C; Capell, M; Commichau, V; Djambazov, L; Fanchiang, Y J; Flügge, G; Fritschi, M; Grimm, O; Hangarter, K; Hofer, H; Horisberger, Urs; Kan, R; Kaestli, W; Kenney, G P; Kim, G N; Kim, K S; Koutsenko, V F; Kraeber, M; Kuipers, J; Lebedev, A; Lee, M W; Lee, S C; Lewis, R; Lustermann, W; Pauss, Felicitas; Rauber, T; Ren, D; Ren, Z L; Röser, U; Son, D; Ting, Samuel C C; Tiwari, A N; Viertel, Gert M; Gunten, H V; Wicki, S W; Wang, T S; Yang, J; Zimmermann, B

    2002-01-01

    The Prototype Synchrotron Radiation Detector (PSRD) is a small-scale experiment designed to measure the rate of low-energy charged particles and photons in near the Earth's orbit. It is a precursor to the Synchrotron Radiation Detector (SRD), a proposed addition to the upgraded version of the Alpha Magnetic Spectrometer (AMS-02). The SRD will use the Earth's magnetic field to identify the charge sign of electrons and positrons with energies above 1 TeV by detecting the synchrotron radiation they emit in this field. The differential energy spectrum of these particles is astrophysically interesting and not well covered by the remaining components of AMS-02. Precise measurements of this spectrum offer the possibility to gain information on the acceleration mechanism and characteristics of all cosmic rays in our galactic neighbourhood. The SRD will discriminate against protons as they radiate only weakly. Both the number and energy of the synchrotron photons that the SRD needs to detect are small. The identificat...

  10. Industrial workshop on LASL semiconductor radiation-detector research and development

    International Nuclear Information System (INIS)

    Endebrock, M.

    1978-11-01

    An Industrial Workshop on LASL Semiconductor Radiation Detector Research and Development was held at the Los Alamos Scientific Laboratory (LASL) in the spring of 1977. The purpose was to initiate communication between our detector research and development program and industry. LASL research programs were discussed with special emphasis on detector problems. Industrial needs and capabilities in detector research and development were also presented. Questions of technology transfer were addressed. The notes presented here are meant to be informal, as were the presentations

  11. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Steer, C.A.; Durose, A.; Boakes, J. [AWE Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

    2015-07-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  12. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    International Nuclear Information System (INIS)

    Steer, C.A.; Durose, A.; Boakes, J.

    2015-01-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  13. Radiation Damage in Silicon Detectors Caused by Hadronic and Electromagnetic Irradiation

    CERN Document Server

    Fretwurst, E.; Stahl, J.; Pintilie, I.

    2002-01-01

    The report contains various aspects of radiation damage in silicon detectors subjected to high intensity hadron and electromagnetic irradiation. It focuses on improvements for the foreseen LHC applications, employing oxygenation of silicon wafers during detector processing (result from CERN-RD48). An updated survey on hadron induced damage is given in the first article. Several improvements are outlined especially with respect to antiannealing problems associated with detector storage during LHC maintenance periods. Open questions are outlined in the final section, among which are a full understanding of differences found between proton and neutron induced damage, process related effects changing the radiation tolerance in addition to the oxygen content and the lack of understanding the changed detector properties on the basis of damage induced point and cluster defects. In addition to float zone silicon, so far entirely used for detector fabrication,Czochralski silicon was also studied and first promising re...

  14. Testing of the effect of the entry beam tube windows of the silicon detectors of the ionisation radiation

    International Nuclear Information System (INIS)

    Kopestansky, J.; Tykva, R.; Stanek, S.

    1995-01-01

    This paper deals with testing of the entry beam tube windows of the silicon detectors of the ionisation radiation with surface barrier.The influence of the parameters of basic material and modified technologic preparation on the size and homogeneity of the windows was tested

  15. Radiative processes for Rindler and accelerating observers and the stress-tensor detector

    International Nuclear Information System (INIS)

    Paola, R. De; Svaiter, N.F.

    1996-04-01

    It is considered a monopole detector interacting with a massive scalar field. Using the rotating wave approximation the radiative processes is discussed from the accelerated frame point of view. After this, it is obtained the Minkowski vacuum stress tensor measured by the accelerated observer using a non-gravitational stress sensor detector. Finally we analyse radiative processes of the monopole detector travelling in a world line that is inertial in the infinite past and has a constant proper acceleration in the infinite future. (author). 30 refs

  16. Detector and quantifier of ionizing x-radiation by indirect method

    International Nuclear Information System (INIS)

    Pablo, Aramayo; Roberto, Cruz; Luis, Rocha; Rotger Viviana I; Olivera, Juan Manuel

    2007-01-01

    The work presents the development of a device able to detect and quantify ionizing radiations. The transduction principle proposed for the design of the detector consists on using the properties of the fluorescent screens able to respond to the incident radiation with a proportional brightness. Though the method is well-known, it proved necessary to optimize the design of the detectors in order to get a greater efficiency in the relationship radiation/brightness; to that purpose, different models were tried out, varying its geometry and the optoelectronic device. The resultant signal was processed and presented in a visualization system. It is important to highlight that the project is in development and the results we obtained are preliminary

  17. Response of a hybrid pixel detector (MEDIPIX3) to different radiation sources for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Chumacero, E. Miguel; De Celis Alonso, B.; Martínez Hernández, M. I.; Vargas, G.; Moreno Barbosa, E., E-mail: emoreno.emb@gmail.com [Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y Rio Verde, Puebla (Mexico); Moreno Barbosa, F. [Hospital General del Sur Hospital de la Mujer, Puebla (Mexico)

    2014-11-07

    The development in semiconductor CMOS technology has enabled the creation of sensitive detectors for a wide range of ionizing radiation. These devices are suitable for photon counting and can be used in imaging and tomography X-ray diagnostics. The Medipix[1] radiation detection system is a hybrid silicon pixel chip developed for particle tracking applications in High Energy Physics. Its exceptional features (high spatial and energy resolution, embedded ultra fast readout, different operation modes, etc.) make the Medipix an attractive device for applications in medical imaging. In this work the energy characterization of a third-generation Medipix chip (Medipix3) coupled to a silicon sensor is presented. We used different radiation sources (strontium 90, iron 55 and americium 241) to obtain the response curve of the hybrid detector as a function of energy. We also studied the contrast of the Medipix as a measure of pixel noise. Finally we studied the response to fluorescence X rays from different target materials (In, Pd and Cd) for the two data acquisition modes of the chip; single pixel mode and charge summing mode.

  18. Characteristics of fabricated si PIN-type radiation detectors on cooling temperature

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Soo; Jeong, Manhee; Kim, Young Soo [Korea Atomic Energy Research Institute, Jeongeup-si 580-185 (Korea, Republic of); Lee, Dong Hun [Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of); Cho, Seung Yeon [Environmental Health Center, Yonsei University, Wonju-si 1184-4 (Korea, Republic of); Ha, Jang Ho [Korea Atomic Energy Research Institute, Jeongeup-si 580-185 (Korea, Republic of)

    2015-06-01

    Si PIN photodiode radiation detectors with three different active areas (3×3 mm{sup 2}, 5×5 mm{sup 2}, and 10×10 mm{sup 2}) were designed and fabricated at the Korea Atomic Energy Research Institute (KAERI) for low energy X- and gamma-ray detection. In Si-based semiconductor radiation detectors, one of the noise sources is thermal noise, which degrades their energy resolution performance. In this study, the temperature effects on the energy resolution were investigated using a 3×3 mm{sup 2} active area PIN photodiode radiation detector using a Thermoelectric Module (TEM) from room temperature to −23 °C. Energy resolutions from 25 keV auger electrons to 81 keV gamma-ray from a Ba-133 calibration source were measured and compared at every 10 °C interval. At −23 °C, energy resolutions were improved by 15.6% at 25 keV, 4.0% at 31 keV, and 1.2% at 81 keV in comparison with resolutions at room temperature. CsI(Tl)/PIN photodiode radiation detectors were also fabricated for relatively high energy gamma-ray detection. Energy resolutions for Cs-137, Co-60, and Na-22 sources were measured and compared with the spectral responsivity.

  19. An intercomparison of detectors for measurement of background radiation

    International Nuclear Information System (INIS)

    Nielsen, S.P.; Boetter-Jensen, L.

    1981-04-01

    Measurements of the background radiation were made in 1978 at 14 locations with a high-pressure ionization chamber, thermoluminiscence dosimeters (TLD's), two NaI(Tl) detectors, and a Ge(Li) spectrometer system. Simultaneous measurements with the ionization chamber and the spectrometer system provide reliable estimates of the total background exposure rate, of the individual contributors to the terrestrial exposure rate, and of the exposure rate from the secondary cosmic radiation. The TLD results agree with those of the ionization chamber. The NaI(Tl) detector results show that accurate estimates of the terrestrial exposure rate can be obtained if empirical corrections are applied. (author)

  20. Dual-Energy Semiconductor Detector of X-rays and Gamma Radiation

    Directory of Open Access Journals (Sweden)

    Brodyn, M.S.

    2014-03-01

    Full Text Available Analysis of the major types of ionizing radiation detectors, their advantages and disadvantages are presented. Application of ZnSe-based semiconductor detector in high temperature environment is substantiated. Different forms of ZnSe-based detector samples and double-crystal scheme for registration of X- and gamma rays in a broad energy range were used . Based on the manufactured simulator device, the study sustains the feasibility of the gamma quanta recording by a high-resistance ZnSe-based detector operating in a perpulse mode.

  1. Mobile robot prototype detector of gamma radiation; Prototipo de robot movil detector de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez C, R.M. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Duran V, M. D.; Jardon M, C. I., E-mail: raulmario.vazquez@inin.gob.mx [Tecnologico de Estudios Superiores de Villa Guerrero, Carretera Federal Toluca-Ixtapan de la Sal Km. 64.5, La Finca Villa Guerrero, Estado de Mexico (Mexico)

    2014-10-15

    In this paper the technological development of a mobile robot prototype detector of gamma radiation is shown. This prototype has been developed for the purpose of algorithms implementation for the applications of terrestrial radiation monitoring of exposed sources, search for missing radioactive sources, identification and delineation of radioactive contamination areas and distribution maps generating of radioactive exposure. Mobile robot detector of radiation is an experimental technology development platform to operate in laboratory environment or flat floor facilities. The prototype integrates a driving section of differential configuration robot on wheels, a support mechanism and rotation of shielded detector, actuator controller cards, acquisition and processing of sensor data, detection algorithms programming and control actuators, data recording (Data Logger) and data transmission in wireless way. The robot in this first phase is remotely operated in wireless way with a range of approximately 150 m line of sight and can extend that range to 300 m or more with the use of signal repeaters. The gamma radiation detection is performed using a Geiger detector shielded. Scan detection is performed at various time sampling periods and diverse positions of discrete or continuous angular orientation on the horizon. The captured data are geographical coordinates of robot GPS (latitude and longitude), orientation angle of shield, counting by sampling time, date, hours, minutes and seconds. The data is saved in a file in the Micro Sd memory on the robot. They are also sent in wireless way by an X Bee card to a remote station that receives for their online monitoring on a laptop through an acquisition program by serial port on Mat Lab. Additionally a voice synthesizing card with a horn, both in the robot, periodically pronounced in Spanish, data length, latitude, orientation angle of shield and detected accounts. (Author)

  2. WORKSHOP: Scintillating fibre detectors

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Scintillating fibre detector development and technology for the proposed US Superconducting Supercollider, SSC, was the subject of a recent workshop at Fermilab, with participation from the high energy physics community and from industry. Sessions covered the current status of fibre technology and fibre detectors, new detector applications, fluorescent materials and scintillation compositions, radiation damage effects, amplification and imaging structures, and scintillation fibre fabrication techniques

  3. Effect of electron transport properties on unipolar CdZnTe radiation detectors: LUND, SpectrumPlus, and Coplanar Grid

    International Nuclear Information System (INIS)

    James, Ralph B.

    2000-01-01

    Device simulations of (1) the laterally-contacted-unipolar-nuclear detector (LUND), (2) the SpectrumPlus, (3) and the coplanar grid made of Cd 0.9 Zn 0.1 Te (CZT) were performed for 137 Cs irradiation by 662.15 keV gamma-rays. Realistic and controlled simulations of the gamma-ray interactions with the CZT material were done using the MCNP4B2 Monte Carlo program, and the detector responses were simulated using the Sandia three-dimensional multielectrode simulation program (SandTMSP). The simulations were done for the best and the worst expected carrier nobilities and lifetimes of currently commercially available CZT materials for radiation detector applications. For the simulated unipolar devices, the active device volumes were relatively large and the energy resolutions were fairly good, but these performance characteristics were found to be very sensitive to the materials properties. The internal electric fields, the weighting potentials, and the charge induced efficiency maps were calculated to give insights into the operation of these devices

  4. Review on the characteristics of radiation detectors for dosimetry and imaging

    International Nuclear Information System (INIS)

    Seco, Joao; Clasie, Ben; Partridge, Mike

    2014-01-01

    The enormous advances in the understanding of human anatomy, physiology and pathology in recent decades have led to ever-improving methods of disease prevention, diagnosis and treatment. Many of these achievements have been enabled, at least in part, by advances in ionizing radiation detectors. Radiology has been transformed by the implementation of multi-slice CT and digital x-ray imaging systems, with silver halide films now largely obsolete for many applications. Nuclear medicine has benefited from more sensitive, faster and higher-resolution detectors delivering ever-higher SPECT and PET image quality. PET/MR systems have been enabled by the development of gamma ray detectors that can operate in high magnetic fields. These huge advances in imaging have enabled equally impressive steps forward in radiotherapy delivery accuracy, with 4DCT, PET and MRI routinely used in treatment planning and online image guidance provided by cone-beam CT. The challenge of ensuring safe, accurate and precise delivery of highly complex radiation fields has also both driven and benefited from advances in radiation detectors. Detector systems have been developed for the measurement of electron, intensity-modulated and modulated arc x-ray, proton and ion beams, and around brachytherapy sources based on a very wide range of technologies. The types of measurement performed are equally wide, encompassing commissioning and quality assurance, reference dosimetry, in vivo dosimetry and personal and environmental monitoring. In this article, we briefly introduce the general physical characteristics and properties that are commonly used to describe the behaviour and performance of both discrete and imaging detectors. The physical principles of operation of calorimeters; ionization and charge detectors; semiconductor, luminescent, scintillating and chemical detectors; and radiochromic and radiographic films are then reviewed and their principle applications discussed. Finally, a general

  5. Detector and dosimeter for neutrons and other radiation

    International Nuclear Information System (INIS)

    Apfel, R.E.

    1979-01-01

    A radiation detector and dosimeter is based on the fact that a sufficiently finely-dispersed liquid suspended in a host liquid of high viscosity or gel is stable at temperatures above its normal boiling point for long periods of time provided it is protected from contact with walls, or other types of initiators which can cause volatilization or vaporization of the droplets. Radiation, and particularly neutron radiation of sufficient energy and intensity on coming in contact with such droplets can trigger volatilization. The volume of vapor evolved can then serve as a measure of radiation intensity and dosage

  6. Development of an X-ray detector using photodiodes; Desarrollo de un detector de rayos X usando fotodiodos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez G, J.; Azorin V, J. C.; Sosa A, M. A.; Ceron, P., E-mail: gonzalezgj2012@licifug.ugto.mx [Universidad de Guanajuato, Division de Ciencias e Ingenierias, Loma del Bosque No. 103, Col. Lomas del Campestre, 37150 Leon, Guanajuato (Mexico)

    2016-10-15

    Currently the radiation detectors for medical applications are very high value in the market and are difficult to access as training material. In the Sciences and Engineering Division of the Guanajuato University (Mexico) investigations are carried out related to ionizing radiations, especially with X-rays. To overcome the lack of materials has had to resort to borrowing equipment from other institutions, so its use and availability are intermittent. For these reasons is proposed to design and implement an X-ray detector for the use of the work group and the University. This work aims to build an X-ray semiconductor detector using inexpensive and affordable materials, is also proposed the use of a photodiode sensor and an Arduino analog-digital card and a LCD display showing the data. (Author)

  7. Development of high temperature, radiation hard detectors based on diamond

    Energy Technology Data Exchange (ETDEWEB)

    Metcalfe, Alex, E-mail: Alex.Metcalfe@brunel.ac.uk [Wolfson Centre for Materials Processing, Brunel University London, Uxbridge UB8 3PH (United Kingdom); Fern, George R. [Wolfson Centre for Materials Processing, Brunel University London, Uxbridge UB8 3PH (United Kingdom); Hobson, Peter R. [Centre for Sensors & Instrumentation, College of Engineering, Design and Physical Sciences, Brunel University London, Uxbridge UB8 3PH (United Kingdom); Ireland, Terry; Salimian, Ali; Silver, Jack [Wolfson Centre for Materials Processing, Brunel University London, Uxbridge UB8 3PH (United Kingdom); Smith, David R. [Centre for Sensors & Instrumentation, College of Engineering, Design and Physical Sciences, Brunel University London, Uxbridge UB8 3PH (United Kingdom); Lefeuvre, Gwenaelle [Micron Semiconductor Ltd., Lancing BN15 8 SJ (United Kingdom); Saenger, Richard [Schlumberger Limited, 91240 Clamart (France)

    2017-02-11

    Single crystal CVD diamond has many desirable properties compared to current, well developed, detector materials; exceptional radiation, chemical and physical hardness, chemical inertness, low Z (close to human tissue, good for dosimetry), wide bandgap and an intrinsic pathway to fast neutron detection through the {sup 12}C(n,α){sup 9}Be reaction. However effective exploitation of these properties requires development of a suitable metallisation scheme to give stable contacts for high temperature applications. To best utilise available processing techniques to optimise sensor response through geometry and conversion media configurations, a reliable model is required. This must assess the performance in terms of spectral response and overall efficiency as a function of detector and converter geometry. The same is also required for proper interpretation of experimental data. Sensors have been fabricated with varying metallisation schemes indented to permit high temperature operation; Present test results indicate that viable fabrication schemes for high temperature contacts have been developed and present modelling results, supported by preliminary data from partners indicate simulations provide a useful representation of response. - Highlights: • Radiation sensors using diamond as the sensitive volume have been constructed. • Functionality of these sensors with minimal degradation has been confirmed at 100 °C. • Sensitisation to thermal neutrons by addition of conversion layers has been modelled. • Modelling suggests 4× efficiency improvements from 3d converter-substrate interfaces.

  8. Recent advances in MEMS radiation detectors for improving radiation safety in nuclear reactors

    International Nuclear Information System (INIS)

    Bhisikar, Abhay

    2016-01-01

    MEMS (micro-electro-mechanical-system) is a core technology that leverages integrated circuit (IC) fabrication technology, builds ultra-miniaturized components and, enables radical new system applications. When considering MEMS radiation detectors; they are the specific micromechanical structures which are designed to sense doses of radiations. The present article reviews the most recent progress made in the domain of MEMS ionizing radiation sensors at international level for nuclear reactors which can be relevant to Indian context. (author)

  9. Fabrication of advanced military radiation detector sensor and performance evaluation

    International Nuclear Information System (INIS)

    Kang, Sin Yang

    2010-02-01

    Recently, our country is facing a continuous nuclear weapons threat. Therefore, we must have a high-level nuclear weapons protection system. The best protection against nuclear weapons is detecting their use to reduce casualties in our country to a minimum. That means, the development of a military radiation detector is a very important issue. The Korea army is using the 'PDR - 1K portable military radiation surveymeter' in NBC (Nuclear, Biological, Chemical warfare) operations. The PDR - 1K military detector can measure beta and gamma rays only but it cannot detect alpha particles. Because of its characteristics, the Korea army has weaknesses in tactical operations. The PDR - 1K sensor is based on a GM - tube sensor system. For the mechanical structure, detectors utilizing a GM-tube sensor do not work on a high - radiation battlefield and they do not carry out nuclide analysis for fixed electron signal output. In the meantime, the United States of America and Germany are using 'AN/PDR - 77' and 'SVG - 2' that were made from scintillator sensors. They have excellent physical qualities and radiation responses for military use. Also, nuclide analysis is available. Therefore, in this study we fabricated a military - grade scintillator radiation sensor that is able to detect alpha, beta, and gamma - rays to overcome PDR - 1K's weaknesses. Also, physical characteristics and radiation response evaluation for the fabricated sensors was carried out. The alpha - particle sensor and beta - ray sensor were fabricated using a ZnS(Ag) powder state scintillator, and a Saint - Gobain organic plastic scintillator BC-408 panel, respectively. The gamma ray sensor was manufactured using a 10 x 10 x 10 mm 3 CsI(Tl) inorganic scintillator crystal. A detailed explanation follows. The alpha particle sensor was fabricated by using air - brushing method to Zns(Ag) powder scintillator spreading. The ZnS(Ag) layer thickness was 35 μm (detection efficiency: 41%). This alpha - particle sensor

  10. Quantitative material decomposition using spectral computed tomography with an energy-resolved photon-counting detector

    International Nuclear Information System (INIS)

    Lee, Seungwan; Choi, Yu-Na; Kim, Hee-Joung

    2014-01-01

    Dual-energy computed tomography (CT) techniques have been used to decompose materials and characterize tissues according to their physical and chemical compositions. However, these techniques are hampered by the limitations of conventional x-ray detectors operated in charge integrating mode. Energy-resolved photon-counting detectors provide spectral information from polychromatic x-rays using multiple energy thresholds. These detectors allow simultaneous acquisition of data in different energy ranges without spectral overlap, resulting in more efficient material decomposition and quantification for dual-energy CT. In this study, a pre-reconstruction dual-energy CT technique based on volume conservation was proposed for three-material decomposition. The technique was combined with iterative reconstruction algorithms by using a ray-driven projector in order to improve the quality of decomposition images and reduce radiation dose. A spectral CT system equipped with a CZT-based photon-counting detector was used to implement the proposed dual-energy CT technique. We obtained dual-energy images of calibration and three-material phantoms consisting of low atomic number materials from the optimal energy bins determined by Monte Carlo simulations. The material decomposition process was accomplished by both the proposed and post-reconstruction dual-energy CT techniques. Linear regression and normalized root-mean-square error (NRMSE) analyses were performed to evaluate the quantitative accuracy of decomposition images. The calibration accuracy of the proposed dual-energy CT technique was higher than that of the post-reconstruction dual-energy CT technique, with fitted slopes of 0.97–1.01 and NRMSEs of 0.20–4.50% for all basis materials. In the three-material phantom study, the proposed dual-energy CT technique decreased the NRMSEs of measured volume fractions by factors of 0.17–0.28 compared to the post-reconstruction dual-energy CT technique. It was concluded that the

  11. Test-beam Results from a RICH Detector Prototype Using Aerogel Radiator and Pixel Hybrid Photon Detectors

    CERN Document Server

    Aglieri-Rinella, G; Van Lysebetten, A; Piedigrossi, D; Wyllie, K; Bellunato, T F; Calvi, M; Matteuzzi, C; Musy, M; Perego, D L; Somerville, L P; Newby, C; Easo, S; Wotton, S

    2006-01-01

    A test-beam study was performed at CERN with a Ring Imaging Cherenkov (RICH) prototype using three pixel Hybrid Photon Detectors. Results on the photon yield and Cherenkov angle resolution are presented here, for the Aerogel radiator and also for reference runs taken with Nitrogen radiator.

  12. Containing and discarding method for radiation contaminated materials and radiation contaminated material containing composite member

    International Nuclear Information System (INIS)

    Akagawa, Katsuhiko.

    1995-01-01

    A container for high level radiation contaminated materials is loaded in an outer container in a state of forming a gap between the outer container and a container wall, low level radiation contaminated materials are filled to the gap between the container of the radiation contaminated materials and the container wall, and then the outer container is sealed. In addition, the thickness of the layer of the low level radiation contaminated materials is made substantially uniform. Then, since radiation rays from the container of the radiation contaminated materials are decayed by the layer of the low level radiation contaminated materials at the periphery of the container and the level of the radiation rays emitted from the outer container is extremely reduced than in a case where the entire amount of high level radiation contaminated materials are filled, the level is suppressed to an extent somewhat higher than the level in the case where the entire amount of the low level radiation contaminated materials are filled. Accordingly, the management corresponds to that for the low level radiation contaminated materials, and the steps for the management and the entire volume thereof are reduced than in a case where the high level radiation contaminated materials and the low level radiation contaminated materials are sealed separately. (N.H.)

  13. X-ray radiation detectors of 'scintillator-photoreceiving device type' for industrial digital radiography with improved spatial resolution

    International Nuclear Information System (INIS)

    Ryzhykov, V.D.; Lysetska, O.K.; Opolonin, O.D.; Kozin, D.N.

    2003-01-01

    Main types of photo receivers used in X-ray digital radiography systems are luminescent screens that transfer the optical image onto charge collection instruments, which require cooling, and semiconductor silicon detectors, which limit the contrast sensitivity. We have developed and produced X-ray radiation detectors of 'scintillator-photoreceiving device' (S-PRD) type, which are integrally located on the inverse side of the photodiode (PD). The receiving-converting circuit (RCC) is designed for data conversion into digital form and their input into PC. Software is provided for RCC control and image visualization. Main advantages of these detectors are high industrial resolution (3-5 line pairs per mm), detecting activity up to 20 μm, controlled sensitivity, low weight and small size, imaging low (0.1-0.3 mrad) object dose in real time. In this work, main characteristics of 32-, 64- and 1024-channel detectors of S-PRD type were studied and compared for X-ray sensitivity with S-PD detectors. Images of the tested objects have been obtained. Recommendations are given on the use of different scintillation materials, depending upon the purpose of a digital radiographic system. The detectors operate in a broad energy range of ionizing radiation, hence the size of the controlled object is not limited. The system is sufficiently powerful to ensure frontal (through two walls) observation of pipelines with wall thickness up to 10 cm

  14. Development of Micro-Pattern Gas Detectors Technologies

    CERN Multimedia

    Richer, J; Barsuk, S; Shah, M K; Catanesi, M G; Colaleo, A; Maggi, M; Loddo, F; Berardi, V; Bagliesi, M; Menon, G; Richter, R; Lahonde-hamdoun, C; Dris, M; Chechik, R; Ochi, A; Hartjes, F; Lopes, I M; Deshpande, A; Franz, A; Fiutowski, T A; Ferreira, A; Bastos de oliveira, C A; Miller, B W; Monrabal-capilla, F; Liubarsky, I; Plazas de pinzon, M C; Tsarfati, T; Voss, B J R; Carmona martinez, J M; Stocchi, A; Dinu, N; Semeniouk, I; Giebels, B; Marton, K; De leo, R; De lucia, E; Alviggi, M; Bellerive, A; Herten, L G; Zimmermann, S U; Giomataris, I; Peyaud, A; Schune, P; Delagnes, E; Delbart, A; Charles, G; Wang, W; Markou, A; Arazi, L; Cibinetto, G; Edo, Y; Neves, F F; Solovov, V; Stoll, S; Sampsonidis, D; Dabrowski, W; Mindur, B; Sauli, F; Calapez de albuquerque veloso, J F; Kahlaoui, N; Sharma, A; Zenker, K; Cebrian guajardo, S V; Luzon marco, G M; Guillaudin, O J H; Cornebise, P; Lounis, A; Bruel, P J; Laszlo, A; Mukerjee, K; Nappi, E; Nuzzo, S V; Bencivenni, G; Tessarotto, F; Levorato, S; Dixit, M S; Riallot, M; Jeanneau, F; Nizery, F G; Maltezos, S; Kyriakis, A; Lyashenko, A; Van der graaf, H; Ferreira marques, R; Alexa, C; Liyanage, N; Dehmelt, K; Hemmick, T K; Polychronakos, V; Cisbani, E; Garibaldi, F; Koperny, S Z; Das neves dias carramate, L F; Munoz-vidal, J; Gutierrez, R; Van stenis, M; Resnati, F; Lupberger, M; Desch, K K; Chefdeville, M; Vouters, G; Ranieri, A; Lami, S; Shekhtman, L; Dolgov, A; Bamberger, A; Landgraf, U; Kortner, O; Ferrero, A; Aune, S; Attie, D M; Bakas, G; Balossino, I; Tsigaridas, S; Surrow, B; Gnanvo, K A K; Feege, N M; Woody, C L; Bhattacharya, S; Capogni, M; Veenhof, R J; Tapan, I; Dangendorf, V; Monteiro bernades, C M; Castro serrato, H F; De oliveira, R; Ropelewski, L; Behnke, T; Boudry, V; Radicioni, E; Lai, A; Shemyakina, E; Giganon, A E; Titov, M; Papakrivopoulos, I; Komai, H; Van bakel, N A; Tchepel, V; Repond, J O; Li, Y; Kourkoumelis, C; Tzamarias, S; Majumdar, N; Kowalski, T; Da rocha azevedo, C D; Serra diaz cano, L; Alvarez puerta, V; Trabelsi, A; Riegler, W; Ketzer, B F; Rosemann, C G; Herrera munoz, D C; Drancourt, C; Mayet, F; Geerebaert, Y; De robertis, G; Felici, G; Scribano memoria, A; Cecchi, R; Dalla torre, S; Gregori, M; Buzulutskov, A; Schwegler, P; Sanchez nieto, F J; Colas, P M A; Gros, M; Neyret, D; Zito, M; Ferrer ribas, E; Breskin, A; Martoiu, V S; Purschke, M L; Loomba, D; Gasik, P J; Petridou, C; Kordas, K; Mukhopadhyay, S; Bucciantonio, M; Biagi, S F; Ji, X; Kanaki, K; Zavazieva, D; Capeans garrido, M D M; Schindler, H; Kaminski, J; Krautscheid, T; Lippmann, C; Arora, R; Dafni, T; Garcia irastorza, I; Puill, V; Wicek, F B; Burmistrov, L; Singh, K P; Kroha, H; Kunne, F; Alexopoulos, T; Daskalakis, G; Geralis, T; Bettoni, D; Heijhoff, K; Xiao, Z; Tzanakos, G; Leisos, A; Frullani, S; Sahin, O; Kalkan, Y; Giboni, K; Krieger, C; Breton, D R; Bhattacharyya, S; Abbrescia, M; Erriquez, O; Paticchio, V; Cardini, A; Aloisio, A; Turini, N; Bressan, A; Tikhonov, Y; Schumacher, M; Simon, F R; Nowak, S; Herlant, S; Chaus, A; Fanourakis, G; Bressler, S; Homma, Y; Timmermans, J; Fonte, P; Underwood, D G; Azmoun, B; Fassouliotis, D; Wiacek, P; Dos santos covita, D; Monteiro da silva, A L; Yahlali haddou, N; Marques ferreira dos santos, J; Domingues amaro, F

    The proposed R&D collaboration, RD51, aims at facilitating the development of advanced gas-avalanche detector technologies and associated electronic-readout systems, for applications in basic and applied research. Advances in particle physics have always been enabled by parallel advances in radiation-detector technology. Radiation detection and imaging with gas-avalanche detectors, capable of economically covering large detection volumes with a low material budget, have been playing an important role in many fields. Besides their widespread use in particle-physics and nuclear-physics experiments, gaseous detectors are employed in many other fields: astro-particle research and applications such as medical imaging, material science, and security inspection. While extensively employed at the LHC, RHIC, and other advanced HEP experiments, present gaseous detectors (wire-chambers, drift-tubes, resistive-plate chambers and others) have limitations which may prevent their use in future experiments. Present tec...

  15. Very Low-Power Consumption Analog Pulse Processing ASIC for Semiconductor Radiation Detectors

    International Nuclear Information System (INIS)

    Wessendorf, K.O.; Lund, J.C.; Brunett, B.A.; Laguna, G.R.; Clements, J.W.

    1999-01-01

    We describe a very-low power consumption circuit for processing the pulses from a semiconductor radiation detector. The circuit was designed for use with a cadmium zinc telluride (CZT) detector for unattended monitoring of stored nuclear materials. The device is intended to be battery powered and operate at low duty-cycles over a long period of time. This system will provide adequate performance for medium resolution gamma-ray pulse-height spectroscopy applications. The circuit incorporates the functions of a charge sensitive preamplifier, shaping amplifier, and peak sample and hold circuit. An application specific integrated circuit (ASIC) version of the design has been designed, built and tested. With the exception of the input field effect transistor (FET), the circuit is constructed using bipolar components. In this paper the design philosophy and measured performance characteristics of the circuit are described

  16. A detector for localizing diverging beams of ionizing radiations

    International Nuclear Information System (INIS)

    Allemand, Robert.

    1974-01-01

    Description is given of a detector for localizing diverging radiation beams, adapted to provide the angular distribution of nuclear events. That detector comprises a casing filled with a fluid adapted to produce electric charges under radiations and provided with a front-side and a rear-side, means for generating an electric field at right angles to portions of parallel surfaces of revolution having in common an axis of revolution contained in the place of symmetry, and a plane unit for localizing electric charges mounted at the rear of said means, the initial portion of the beam being on the axis of revolution. This can be applied to X-ray diffraction and to neutron diffraction [fr

  17. Multi-detector environmental radiation monitor with multichannel data communication for Indian Environmental Radiation Monitoring Network (IERMON)

    International Nuclear Information System (INIS)

    Patel, M.D.; Ratheesh, M.P.; Prakasha, M.S.; Salunkhe, S.S.; Vinod Kumar, A.; Puranik, V.D.; Nair, C.K.G.

    2011-01-01

    A solar powered system for online monitoring of environmental radiation with multiple detectors has been designed, developed and produced. Multiple GM tube detectors have been used to extend the range of measurement from 50 nano Gy/hr to 20 Gy/hr and to enhance the reliability of the system. Online data communication using GSM based and direct LAN based communication has been incorporated. Options for use of power supply from mains powered and battery powered have been enabled. Care has been taken to make it weather-proof, compact, elegant and reliable. The development is a part of the ongoing program of country-wide deployment of radiation monitors under 'Indian Environmental Radiation MOnitoring Network' (IERMON). (author)

  18. Measurement with self-powered cobalt and cadmium detectors

    International Nuclear Information System (INIS)

    Azzoni, A.

    The principle of function is described and the characteristics are given of self-powered cobalt and cadmium neutron detectors. Requirements are summed up for the material used for these detectors, and the specific properties of used detectors are given. The calibration of developed self-powered detectors was carried out using the L 54 CESNEF reactor channels with a maximum output of 40 kW and a neutron flux of 10 10 to 10 12 n.cm -2 s -1 . The absolute measurement of neutron flux and gamma radiation doses in the channel were carried out at an output of 10 kW. The objective of calibration measurements with cadmium and cobalt detectors was to ascertain the promptness of detector response, to determine their sensitivity to neutrons and to gamma radiation, the effects of radiation on the material of the detectors and the contribution thereof on the resulting signal. Inside the CART irradiation channel of the ESSOR reactor three such detectors were used for the measurement of neutron flux and its fluctuations effected by coolant density fluctuations. The behaviour of the detectors was studied in a high neutron flux (10 14 n.cm -2 s -1 ) and at long-term irradiation. It was found that cobalt detectors may be used to advantage for measuring the neutron flux if prompt response is required. The high sensitivity to gamma radiation does, however, limit their uses. Cadmium detectors are sensitive to the neutron flux (currents of several mA with a neutron flux of approximately 10 14 n.cm -2 s -1 ) while response to gamma radiation is considerably limited. These detectors are advantageous for short-term use, such as neutron flux mapping and measuring fluctuations. (B.S.)

  19. A review of advances in pixel detectors for experiments with high rate and radiation

    Science.gov (United States)

    Garcia-Sciveres, Maurice; Wermes, Norbert

    2018-06-01

    The large Hadron collider (LHC) experiments ATLAS and CMS have established hybrid pixel detectors as the instrument of choice for particle tracking and vertexing in high rate and radiation environments, as they operate close to the LHC interaction points. With the high luminosity-LHC upgrade now in sight, for which the tracking detectors will be completely replaced, new generations of pixel detectors are being devised. They have to address enormous challenges in terms of data throughput and radiation levels, ionizing and non-ionizing, that harm the sensing and readout parts of pixel detectors alike. Advances in microelectronics and microprocessing technologies now enable large scale detector designs with unprecedented performance in measurement precision (space and time), radiation hard sensors and readout chips, hybridization techniques, lightweight supports, and fully monolithic approaches to meet these challenges. This paper reviews the world-wide effort on these developments.

  20. Passivation layer of Si/Li ionizing radiation detectors

    International Nuclear Information System (INIS)

    Vidra, M.; Reznicek, L.

    1992-01-01

    The proposed passivating layer of Si/Li ionizing radiation detectors ensures a good long-time stability of their volt-ampere characteristics and noise properties. The layer can be applied to protect the detector junction surface in systems cyclically cooled to liquid nitrogen temperature, and in preamplifier feedback optoelectronics to prevent light from entering into the detector. The passivating layer is obtained by evaporating solvent from a cured suspension of boron nitride or aluminium oxide powder in a solution containing piceine and a nonpolar solvent such as toluene. The weight proportions are 1 to 8 parts of piceine, 3 to 9 parts of boron nitride or aluminium oxide, and 1 to 10 parts of the nonpolar solvent. (Z.S.)

  1. Progress in the development of explosives materials detectors

    International Nuclear Information System (INIS)

    Williams, W.D.; Conrad, F.J.; Sandlin, L.L.; Burrows, T.A.

    1978-01-01

    Five hand-held explosives vapor detectors (Elscint Model EXD-2, ITI Model 70, Leigh-Marsland Model S-201, Pye Dynamics Model PD.2.A, and Xonics Model GC-710) were evaluated for sensitivity to a variety of explosives, identification of false alarm agents, and general performance and maintenance characteristics. The results of this evaluation, as presented, indicate that there is no single explosives detector which is best-suited for use at all nuclear facilities. Rather, there are several site-specific elements which must be considered when choosing an explosives detector. There are several new explosives detector technologies being developed which will out-perform existing commercial equipment. Some of these new detectors may be commercially available by the end of fiscal year 1980 and will be cost-effective to purchase and operate. The following areas of explosives detection research are discussed: nitrogen-phosphorous detectors, plasma chromatography, mass spectroscopy, small animal olfactory, vapor preconcentration, nuclear quadrupole resonance, far infrared radiation imaging, nuclear magnetic resonance, thermal neutron activation, and computerized tomography

  2. Results of radiation tests at cryogenic temperature on some selected organic materials for the LHC

    International Nuclear Information System (INIS)

    Tavlet, M.; Schoenbacher, H.

    1999-01-01

    In the near future, particle accelerators and detectors as well as fusion reactors will operate at cryogenic temperatures. At temperatures as low as 2 K, the organic materials used for the insulation of the superconducting magnets and cables will be exposed to high radiation levels. In this work, a representative selection of organic materials comprising insulating films, cable insulations and epoxy-type-impregnated resins were exposed to neutron and gamma radiation of nuclear reactors, both at ambient and cryogenic temperatures, and were subsequently mechanically tested. The results show that the radiation degradation is never worse in a cryogenic fluid than it is in usual ambient conditions. (author)

  3. Improvement of radiation response characteristic on CdTe detectors using fast neutron irradiation

    International Nuclear Information System (INIS)

    Miyamaru, Hiroyuki; Takahashi, Akito; Iida, Toshiyuki

    1999-01-01

    The treatment of fast neutron pre-irradiation was applied to a CdTe radiation detector in order to improve radiation response characteristic. Electron transport property of the detector was changed by the irradiation effect to suppress pulse amplitude fluctuation in risetime. Spectroscopic performance of the pre-irradiated detector was compared with the original. Additionally, the pre-irradiated detector was employed with a detection system using electrical signal processing of risetime discrimination (RTD). Pulse height spectra of 241 Am, 133 Ba, and 137 Cs gamma rays were measured to examine the change of the detector performance. The experimental results indicated that response characteristic for high-energy photons was improved by the pre-irradiation. The combination of the pre-irradiated detector and the RTD processing was found to provide further enhancement of the energy resolution. Application of fast neutron irradiation effect to the CdTe detector was demonstrated. (author)

  4. Preparation of domestic detector using solutions of the scintillation materials (Acridine) and (Eosin)

    International Nuclear Information System (INIS)

    Yousuf, R.M.; Najam, I.A.

    2009-01-01

    In this work, three types of scintillation materials. Acridine orange, Eosin blue and Eosin yellow, were used to act as liquid scintillation detectors. They can be used to detect ionizing radiation, especially that of high Linear Energy Transfer (Let). This work determines the optimum concentration for each of the investigated materials to be 0.2 g/1 dissolved in methanol, added to a solution of Anthracene in Xylene of the concentration of 1.4 g/1 and a solution of POPOP in Xylene of the concentration of 0.2 g/1. All samples were irradiated using radioactive sources 241 Am, 137 Cs and 60 Co. (authors).

  5. Status of diamond particle detectors

    Science.gov (United States)

    Krammer, M.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fish, D.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knöpfle, K. T.; Manfredi, P. F.; Meier, D.; Mishina, M.; LeNormand, F.; Pan, L. S.; Pernegger, H.; Pernicka, M.; Re, V.; Riester, G. L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.

    1998-11-01

    To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given.

  6. Radiation Response of Forward Biased Float Zone and Magnetic Czochralski Silicon Detectors of Different Geometry for 1-MeV Neutron Equivalent Fluence Monitoring

    CERN Document Server

    Mekki, J; Dusseau, Laurent; Roche, Nicolas Jean-Henri; Saigne, Frederic; Mekki, Julien; Glaser, Maurice

    2010-01-01

    Aiming at evaluating new options for radiation monitoring sensors in LHC/SLHC experiments, the radiation responses of FZ and MCz custom made silicon detectors of different geometry have been studied up to about 4 x 10(14) n(eq)/cm(2). The radiation response of the devices under investigation is discussed in terms of material type, thickness and active area influence.

  7. Contrast-enhanced spectral mammography based on a photon-counting detector: quantitative accuracy and radiation dose

    Science.gov (United States)

    Lee, Seungwan; Kang, Sooncheol; Eom, Jisoo

    2017-03-01

    Contrast-enhanced mammography has been used to demonstrate functional information about a breast tumor by injecting contrast agents. However, a conventional technique with a single exposure degrades the efficiency of tumor detection due to structure overlapping. Dual-energy techniques with energy-integrating detectors (EIDs) also cause an increase of radiation dose and an inaccuracy of material decomposition due to the limitations of EIDs. On the other hands, spectral mammography with photon-counting detectors (PCDs) is able to resolve the issues induced by the conventional technique and EIDs using their energy-discrimination capabilities. In this study, the contrast-enhanced spectral mammography based on a PCD was implemented by using a polychromatic dual-energy model, and the proposed technique was compared with the dual-energy technique with an EID in terms of quantitative accuracy and radiation dose. The results showed that the proposed technique improved the quantitative accuracy as well as reduced radiation dose comparing to the dual-energy technique with an EID. The quantitative accuracy of the contrast-enhanced spectral mammography based on a PCD was slightly improved as a function of radiation dose. Therefore, the contrast-enhanced spectral mammography based on a PCD is able to provide useful information for detecting breast tumors and improving diagnostic accuracy.

  8. High spatial resolution radiation detectors based on hydrogenated amorphous silicon and scintillator

    International Nuclear Information System (INIS)

    Jing, T.; Lawrence Berkeley Lab., CA

    1995-05-01

    Hydrogenated amorphous silicon (a-Si:H) as a large-area thin film semiconductor with ease of doping and low-cost fabrication capability has given a new impetus to the field of imaging sensors; its high radiation resistance also makes it a good material for radiation detectors. In addition, large-area microelectronics based on a-Si:H or polysilicon can be made with full integration of peripheral circuits, including readout switches and shift registers on the same substrate. Thin a-Si:H p-i-n photodiodes coupled to suitable scintillators are shown to be suitable for detecting charged particles, electrons, and X-rays. The response speed of CsI/a-Si:H diode combinations to individual particulate radiation is limited by the scintillation light decay since the charge collection time of the diode is very short (< 10ns). The reverse current of the detector is analyzed in term of contact injection, thermal generation, field enhanced emission (Poole-Frenkel effect), and edge leakage. A good collection efficiency for a diode is obtained by optimizing the p layer of the diode thickness and composition. The CsI(Tl) scintillator coupled to an a-Si:H photodiode detector shows a capability for detecting minimum ionizing particles with S/N ∼20. In such an arrangement a p-i-n diode is operated in a photovoltaic mode (reverse bias). In addition, a p-i-n diode can also work as a photoconductor under forward bias and produces a gain yield of 3--8 for shaping times of 1 micros. The mechanism of the formation of structured CsI scintillator layers is analyzed. Initial nucleation in the deposited layer is sensitive to the type of substrate medium, with imperfections generally catalyzing nucleation. Therefore, the microgeometry of a patterned substrate has a significant effect on the structure of the CsI growth

  9. High spatial resolution radiation detectors based on hydrogenated amorphous silicon and scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Jing, Tao [Univ. of California, Berkeley, CA (United States). Dept. of Engineering-Nuclear Engineering

    1995-05-01

    Hydrogenated amorphous silicon (a-Si:H) as a large-area thin film semiconductor with ease of doping and low-cost fabrication capability has given a new impetus to the field of imaging sensors; its high radiation resistance also makes it a good material for radiation detectors. In addition, large-area microelectronics based on a-Si:H or polysilicon can be made with full integration of peripheral circuits, including readout switches and shift registers on the same substrate. Thin a-Si:H p-i-n photodiodes coupled to suitable scintillators are shown to be suitable for detecting charged particles, electrons, and X-rays. The response speed of CsI/a-Si:H diode combinations to individual particulate radiation is limited by the scintillation light decay since the charge collection time of the diode is very short (< 10ns). The reverse current of the detector is analyzed in term of contact injection, thermal generation, field enhanced emission (Poole-Frenkel effect), and edge leakage. A good collection efficiency for a diode is obtained by optimizing the p layer of the diode thickness and composition. The CsI(Tl) scintillator coupled to an a-Si:H photodiode detector shows a capability for detecting minimum ionizing particles with S/N ~20. In such an arrangement a p-i-n diode is operated in a photovoltaic mode (reverse bias). In addition, a p-i-n diode can also work as a photoconductor under forward bias and produces a gain yield of 3--8 for shaping times of 1 {micro}s. The mechanism of the formation of structured CsI scintillator layers is analyzed. Initial nucleation in the deposited layer is sensitive to the type of substrate medium, with imperfections generally catalyzing nucleation. Therefore, the microgeometry of a patterned substrate has a significant effect on the structure of the CsI growth.

  10. The ALICE Transition Radiation Detector: status and perspectives for Run II

    CERN Document Server

    Klein, Jochen

    2016-01-01

    The ALICE Transition Radiation Detector contributes to the tracking, particle identification, and triggering capabilities of the experiment. It is composed of six layers of multi-wire proportional chambers, each of which is preceded by a radiator and a Xe/CO$_2$-filled drift volume. The signal is sampled in timebins of 100~ns over the drift length which allows for the reconstruction of chamber-wise track segments, both online and offline. The particle identification is based on the specific energy loss of charged particles and additional transition radiation photons, the latter being a signature for electrons. The detector is segmented into 18 sectors, of which 13 were installed in Run I. The TRD was included in data taking since the LHC start-up and was successfully used for electron identification and triggering. During the Long Shutdown 1, the detector was completed and now covers the full azimuthal acceptance. Furthermore, the readout and trigger components were upgraded. When data taking was started for ...

  11. Thermal noise in mid-infrared broadband upconversion detectors

    DEFF Research Database (Denmark)

    Barh, Ajanta; Tidemand-Lichtenberg, Peter; Pedersen, Christian

    2018-01-01

    Low noise detection with state-of-the-art mid-infrared (MIR) detectors (e.g., PbS, PbSe, InSb, HgCdTe) is a primary challenge owing to the intrinsic thermal background radiation of the low bandgap detector material itself. However, researchers have employed frequency upconversion based detectors...... of the noise-equivalent power of an UCD system. In this article, we rigorously analyze the optical power generated by frequency upconversion of the intrinsic black-body radiation in the nonlinear material itself due to the crystals residual emissivity, i.e. absorption. The thermal radiation is particularly...... prominent at the optical absorption edge of the nonlinear material even at room temperature. We consider a conventional periodically poled lithium niobate (PPLN) based MIR-UCD for the investigation. The UCD is designed to cover a broad spectral range, overlapping with the entire absorption edge of the PPLN...

  12. Surprising radiation detectors

    CERN Document Server

    Fleischer, Robert

    2003-01-01

    Radiation doses received by the human body can be measured indirectly and retrospectively by counting the tracks left by particles in ordinary objects like pair of spectacles, glassware, compact disks...This method has been successfully applied to determine neutron radiation doses received 50 years ago on the Hiroshima site. Neutrons themselves do not leave tracks in bulk matter but glass contains atoms of uranium that may fission when hurt by a neutron, the recoil of the fission fragments generates a track that is detectable. The most difficult is to find adequate glass items and to evaluate the radiation shield they benefited at their initial place. The same method has been used to determine the radiation dose due to the pile-up of radon in houses. In that case the tracks left by alpha particles due to the radioactive decay of polonium-210 have been counted on the superficial layer of the window panes. Other materials like polycarbonate plastics have been used to determine the radiation dose due to heavy io...

  13. Semiconductor scintillator detector for gamma radiation; Detector cintilador semicondutor para radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Laan, F.T.V. der; Borges, V.; Zabadal, J.R.S., E-mail: ftvdl@ufrgs.br, E-mail: borges@ufrgs.br, E-mail: jorge.zabadal@ufrgs.br [Universidade Federal do Rio Grande do Sul (GENUC/DEMEC/UFRGS), Porto Alegre, RS (Brazil). Grupo de Estudos Nucleares. Departamento de Engenharia Mecanica

    2015-07-01

    Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and thermoluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD's (Electronic Personal Dosemeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were successfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm anthracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cumulative doses for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important features of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum. (author)

  14. Contamination detector for inner surface of container

    International Nuclear Information System (INIS)

    Watanabe, Tadao.

    1995-01-01

    The present invention concerns a device for detecting contamination of radioactive materials on the inner surface of a vessel upon reutilizing the vessel for containing solidified radioactive wastes and transporting them. Namely, the detecting device has following functions. (1) A radiation detector detects the radioactive materials on the inner surface of the vessel. (2) A plurality of proximity switches measure the distance from the radiation detector to the wall surface of the vessel and are actuated if the distance is decreased to a predetermined value, (3) A vessel inner surface position calculation mechanism calculates the position of the inner surface of the vessel based on the information from a direction indicator and a height indicator. (4) A frontal limit detector detects the limit for allowing the radiation detector to proceed. (5) A vessel inner shape judging mechanism for judging the shape of the inner side of the vessel based on the signals from the proximity switches in a state where the frontal limit detector is operated and a vessel inner surface position signal outputted from the vessel inner surface position calculation mechanism. As a result, the shape of the inner side of the vessel can accurately be recognized, thereby improving accuracy of radiation measurement. (I.S.)

  15. Performance of an LPD prototype detector at MHz frame rates under Synchrotron and FEL radiation

    Science.gov (United States)

    Koch, A.; Hart, M.; Nicholls, T.; Angelsen, C.; Coughlan, J.; French, M.; Hauf, S.; Kuster, M.; Sztuk-Dambietz, J.; Turcato, M.; Carini, G. A.; Chollet, M.; Herrmann, S. C.; Lemke, H. T.; Nelson, S.; Song, S.; Weaver, M.; Zhu, D.; Meents, A.; Fischer, P.

    2013-11-01

    A MHz frame rate X-ray area detector (LPD — Large Pixel Detector) is under development by the Rutherford Appleton Laboratory for the European XFEL. The detector will have 1 million pixels and allows analogue storage of 512 images taken at 4.5 MHz in the detector front end. The LPD detector has 500 μm thick silicon sensor tiles that are bump bonded to a readout ASIC. The ASIC's preamplifier provides relatively low noise at high speed which results in a high dynamic range of 105 photons over an energy range of 5-20 keV. Small scale prototypes of 32 × 256 pixels (LPD 2-Tile detector) and 256 × 256 pixels (LPD supermodule detector) are now available for X-ray tests. The performance of prototypes of the detector is reported for first tests under synchrotron radiation (PETRA III at DESY) and Free-Electron-Laser radiation (LCLS at SLAC). The initial performance of the detector in terms of signal range and noise, radiation hardness and spatial and temporal response are reported. The main result is that the 4.5 MHz sampling detection chain is reliably working, including the analogue on-chip memory concept. The detector is at least radiation hard up to 5 MGy at 12 keV. In addition the multiple gain concept has been demonstrated over a dynamic range to 104 at 12 keV with a readout noise equivalent to < 1 photon rms in its most sensitive mode.

  16. Development of a stable and sensitive semiconductor detector by using a mixture of lead(II) iodide and lead monoxide for NDT radiation dose detection

    Science.gov (United States)

    Heo, Y. J.; Kim, K. T.; Han, M. J.; Moon, C. W.; Kim, J. E.; Park, J. K.; Park, S. K.

    2018-03-01

    Recently, high-energy radiation has been widely used in various industrial fields, including the medical industry, and increasing research efforts have been devoted to the development of radiation detectors to be used with high-energy radiation. In particular, nondestructive industrial applications use high-energy radiation for ships and multilayered objects for accurate inspection. Therefore, it is crucial to verify the accuracy of radiation dose measurements and evaluate the precision and reproducibility of the radiation output dose. Representative detectors currently used for detecting the dose in high-energy regions include Si diodes, diamond diodes, and ionization chambers. However, the process of preparing these detectors is complex in addition to the processes of conducting dosimetric measurements, analysis, and evaluation. Furthermore, the minimum size that can be prepared for a detector is limited. In the present study, the disadvantages of original detectors are compensated by the development of a detector made of a mixture of polycrystalline PbI2 and PbO powder, which are both excellent semiconducting materials suitable for detecting high-energy gamma rays and X-rays. The proposed detector shows characteristics of excellent reproducibility and stable signal detection in response to the changes in energy, and was analyzed for its applicability. Moreover, the detector was prepared through a simple process of particle-in-binder to gain control over the thickness and meet the specific value designated by the user. A mixture mass ratio with the highest reproducibility was determined through reproducibility testing with respect to changes in the photon energy. The proposed detector was evaluated for its detection response characteristics with respect to high-energy photon beam, in terms of dose-rate dependence, sensitivity, and linearity evaluation. In the reproducibility assessment, the detector made with 15 wt% PbO powder showed the best characteristics of 0

  17. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    International Nuclear Information System (INIS)

    Kagan, Harris; Gan, K.K.; Kass, Richard

    2009-01-01

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2013, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  18. Semidetector-radiation detector arrangement, as well as its application in a tomographic scanner, in a device to determine radiation intensity or to measure the radiation penetration or absorption

    International Nuclear Information System (INIS)

    Kaufman, L.; Hosier, K.E. Jr.

    1979-01-01

    The CdTe detector or a plate with several CdTe or HgI 2 detectors is suitable for use in computer controlled tomographic X-ray scanners. The detector is used in connection with a pulsed radiation source (Am 241) and a frequency filter technique for measuring the resulting electrical charge pulse of the detector. Merely a narrow frequency band is selected according to the measured duration of the incident radiation pulses. (DG) [de

  19. Evaluation of the effects of high energy X-ray radiation in materials used in dental restorations

    International Nuclear Information System (INIS)

    Maio, Mireia Florencio; Santos, Adimir dos; Fernandes, Marco Antonio Rodrigues

    2011-01-01

    This work studied the behavior of the physical features and chemical composition of materials used in dental restorations (titanium, amalgam, composite resin and glass ionomer cement) which were submitted to x-ray radiation of 6.0 Mega-Volt (MV) of energy produced in a linear accelerator that is used in radiotherapy of head and neck tumors 1 2. The samples were analyzed using a x-ray fluorescence technique by comparing the chemical composition before and after irradiation. In order to check the residual radiation in the samples, measurements of the sample dosimetry were performed with Geiger-Mueller radiation detectors and an ionization chamber. The samples were also analyzed by gamma-ray spectrometry using a hyper-pure Germanium (HPGe) detector. From these tests, we aimed to verify small changes in the composition of the test bodies due to the radiation. (author)

  20. Evaluation of the effects of high energy X-ray radiation in materials used in dental restorations

    Energy Technology Data Exchange (ETDEWEB)

    Maio, Mireia Florencio; Santos, Adimir dos, E-mail: mfmaio@ipen.br, E-mail: asantos@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandes, Marco Antonio Rodrigues, E-mail: marfernandes@fmb.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Departamento de Radioterapia

    2011-07-01

    This work studied the behavior of the physical features and chemical composition of materials used in dental restorations (titanium, amalgam, composite resin and glass ionomer cement) which were submitted to x-ray radiation of 6.0 Mega-Volt (MV) of energy produced in a linear accelerator that is used in radiotherapy of head and neck tumors 1 2. The samples were analyzed using a x-ray fluorescence technique by comparing the chemical composition before and after irradiation. In order to check the residual radiation in the samples, measurements of the sample dosimetry were performed with Geiger-Mueller radiation detectors and an ionization chamber. The samples were also analyzed by gamma-ray spectrometry using a hyper-pure Germanium (HPGe) detector. From these tests, we aimed to verify small changes in the composition of the test bodies due to the radiation. (author)

  1. High purity liquid phase epitaxial gallium arsenide nuclear radiation detector

    International Nuclear Information System (INIS)

    Alexiev, D.; Butcher, K.S.A.

    1991-11-01

    Surface barrier radiation detector made from high purity liquid phase epitaxial gallium arsenide wafers have been operated as X- and γ-ray detectors at various operating temperatures. Low energy isotopes are resolved including 241 Am at 40 deg C. and the higher gamma energies of 235 U at -80 deg C. 15 refs., 1 tab., 6 figs

  2. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    International Nuclear Information System (INIS)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J.

    2015-01-01

    PRD3000 TM is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  3. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J. [Mirion Technologies - MGPI SA (France)

    2015-07-01

    PRD3000{sup TM} is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  4. Using synchrotron radiation angiography with a highly sensitive detector to identify impaired peripheral perfusion in rat pulmonary emphysema

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiromichi [University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Matsushita, Shonosuke, E-mail: shomatsu@md.tsukuba.ac.jp [University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Tsukuba University of Technology, Tsukuba, Ibaraki 305-8521 (Japan); Hyodo, Kazuyuki [High Energy Accelerator Research Organization, KEK, Tsukuba, Ibaraki 305-0801 (Japan); Sato, Yukio; Sakakibara, Yuzuru [University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan)

    2013-03-01

    Synchrotron radiation angiography with a HARP detector made it possible to evaluate impaired pulmonary microcirculation in pulmonary emphysema by means of high sensitivity. Owing to limitations in spatial resolution and sensitivity, it is difficult for conventional angiography to detect minute changes of perfusion in diffuse lung diseases, including pulmonary emphysema (PE). However, a high-gain avalanche rushing amorphous photoconductor (HARP) detector can give high sensitivity to synchrotron radiation (SR) angiography. SR angiography with a HARP detector provides high spatial resolution and sensitivity in addition to time resolution owing to its angiographic nature. The purpose of this study was to investigate whether this SR angiography with a HARP detector could evaluate altered microcirculation in PE. Two groups of rats were used: group PE and group C (control). Transvenous SR angiography with a HARP detector was performed and histopathological findings were compared. Peak density of contrast material in peripheral lung was lower in group PE than group C (p < 0.01). The slope of the linear regression line in scattering diagrams was also lower in group PE than C (p < 0.05). The correlation between the slope and extent of PE in histopathology showed significant negative correlation (p < 0.05, r = 0.61). SR angiography with a HARP detector made it possible to identify impaired microcirculation in PE by means of its high spatial resolution and sensitivity.

  5. Using synchrotron radiation angiography with a highly sensitive detector to identify impaired peripheral perfusion in rat pulmonary emphysema

    International Nuclear Information System (INIS)

    Ito, Hiromichi; Matsushita, Shonosuke; Hyodo, Kazuyuki; Sato, Yukio; Sakakibara, Yuzuru

    2013-01-01

    Synchrotron radiation angiography with a HARP detector made it possible to evaluate impaired pulmonary microcirculation in pulmonary emphysema by means of high sensitivity. Owing to limitations in spatial resolution and sensitivity, it is difficult for conventional angiography to detect minute changes of perfusion in diffuse lung diseases, including pulmonary emphysema (PE). However, a high-gain avalanche rushing amorphous photoconductor (HARP) detector can give high sensitivity to synchrotron radiation (SR) angiography. SR angiography with a HARP detector provides high spatial resolution and sensitivity in addition to time resolution owing to its angiographic nature. The purpose of this study was to investigate whether this SR angiography with a HARP detector could evaluate altered microcirculation in PE. Two groups of rats were used: group PE and group C (control). Transvenous SR angiography with a HARP detector was performed and histopathological findings were compared. Peak density of contrast material in peripheral lung was lower in group PE than group C (p < 0.01). The slope of the linear regression line in scattering diagrams was also lower in group PE than C (p < 0.05). The correlation between the slope and extent of PE in histopathology showed significant negative correlation (p < 0.05, r = 0.61). SR angiography with a HARP detector made it possible to identify impaired microcirculation in PE by means of its high spatial resolution and sensitivity

  6. Ionization detector with improved radiation source

    International Nuclear Information System (INIS)

    Solomon, E.F.

    1977-01-01

    The detector comprises a chamber having at least one radiation source disposed therein. The chamber includes spaced collector plates which form a part of a detection circuit for sensing changes in the ionization current in the chamber. The radiation source in one embodiment is in the form of a wound wire or ribbon suitably supported in the chamber and preferably a source of beta particles. The chamber may also include an adjustable electrode and the source may function as an adjustable current source by forming the wire or ribbon in an eliptical shape and rotating the structure. In another embodiment the source has a random shape and is homogeneously disposed in the chamber. 13 claims, 5 drawing figures

  7. Radiation damage monitoring in the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Seidel, Sally

    2013-01-01

    We describe the implementation of radiation damage monitoring using measurement of leakage current in the ATLAS silicon pixel sensors. The dependence of the leakage current upon the integrated luminosity is presented. The measurement of the radiation damage corresponding to an integrated luminosity 5.6 fb −1 is presented along with a comparison to a model. -- Highlights: ► Radiation damage monitoring via silicon leakage current is implemented in the ATLAS (LHC) pixel detector. ► Leakage currents measured are consistent with the Hamburg/Dortmund model. ► This information can be used to validate the ATLAS simulation model.

  8. Methodology optimization of the thallium bromide crystal preparation for application as a radiation detector

    International Nuclear Information System (INIS)

    Santos, Robinson Alves dos

    2012-01-01

    In this work, TlBr crystals have been purified and grown by the Repeated Bridgman method from commercial TlBr materials and characterized to be used as radiation detectors. To evaluate the purification efficiency, studies on the impurity concentration decrease were performed after each growth, analyzing the trace impurities by inductively coupled plasma mass spectroscopy (ICP-MS). A significant decrease of the concentration of impurities in function of the purification number was observed. The grown crystals presented good crystalline quality according to the results of the x-ray diffraction analysis. To evaluate the crystals to be used as a semiconductor detector, measurements of the resistivity and the pulse height under 241 Am gamma rays were carried out. The radiation response was strongly dependent on the crystal purity. The Repeated Bridgman technique showed to be effective to reduce the concentration of impurities and to improve the TlBr crystal quality to be used as a radiation semiconductor detector. A compartmental model was proposed to fit the concentration/segregation of impurities in function of the Bridgman growth step number. This compartmental model is defined by differential equations and can be used to calculate the rate of migration of impurities. It proved to be a useful tool in predicting the number of Bridgman growth repetitions necessary to achieve the desired impurity concentration. The difference of the impurity migration rates between the crystals grown, using salts from different origins, was significant. Therefore, the choice of the starting salt should be performed experimentally, regardless of the statement nominal purity. (author)

  9. Operation and radiation resistance of a FOXFET biasing structure for silicon strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, M [Particle Detector Group, Fermilab, Batavia, IL (United States) Research Inst. for High Energy Physics (SEFT), Helsinski (Finland); Singh, P; Engels, E Jr; Shepard, J; Shepard, P F [Dept. of Physics and Astronomy, Univ. Pittsburgh, PA (United States)

    1993-03-01

    AC-coupled strip detectors biased with a FOXFET transistor structure have been studied. Measurement results for the basic operational characteristics of the FOXFET are presented together with a brief description of the physics underlying its operation. Radiation effects were studied using photons from a [sup 137]Cs source. Changes in the FOXFET characteristics as a function of radiation dose up to 1 Mrad are reported. Results about the effect of radiation on the noise from a FOXFET biased detector are discribed. (orig.).

  10. Operation and radiation resistance of a FOXFET biasing structure for silicon strip detectors

    International Nuclear Information System (INIS)

    Laakso, M.; Helsinki Univ.; Singh, P.; Engels, E. Jr.; Shepard, P.

    1992-02-01

    AC-coupled strip detectors biased with a FOXFET transistor structure have been studied. Measurement results for the basic operational characteristics of the FOXFET are presented together with a brief description of the physics underlying its operation. Radiation effects were studied using photons from a 137 Cs source. Changes in the FOXFET characteristics as a function of radiation dose up to 1 MRad are reported. Results about the effect of radiation on the noise from a FOXFET biased detector are described. 13 refs

  11. Design of a wire imaging synchrotron radiation detector

    International Nuclear Information System (INIS)

    Kent, J.; Gomez-Cadenas, J.J.; Hogan, A.; King, M.; Rowe, W.; Watson, S.; Von Zanthier, C.; Briggs, D.D.; Levi, M.

    1990-01-01

    This paper documents the design of a detector invented to measure the positions of synchrotron radiation beams for the precision energy spectrometers of the Stanford Linear Collider (SLC). The energy measurements involve the determination, on a pulse-by-pulse basis, of the separation of pairs of intense beams of synchrotron photons in the MeV energy range. The detector intercepts the beams with arrays of fine wires. The ejection of Compton recoil electrons results in charges being developed in the wires, thus enabling a determination of beam positions. 10 refs., 4 figs

  12. Jagiellonian University Radiation Damage in Silicon Particle Detectors in High Luminosity Experiments

    CERN Document Server

    Oblakowska-Mucha, A

    2017-01-01

    Radiation damage is nowadays the most serious problem in silicon particle detectors placed in the very harsh radiation environment. This problem will be even more pronounced after the LHC Upgrade because of extremely strong particle fluences never encountered before. In this review, a few aspects of radiation damage in silicon trackers are presented. Among them, the change in the silicon lattice and its influence on the detector performance are discussed. Currently applied solutions and the new ideas for future experiments will be also shown. Most of the results presented in this summary were obtained within the RD50 Collaboration

  13. Gaschromatographic proof of nitrous oxide concentrations in air by means of radiation ionization detectors

    International Nuclear Information System (INIS)

    Popp, P.; Schoentube, E.; Oppermann, G.

    1985-01-01

    For the analysis of nitrous oxide concentrations at workplaces in operating theatres, gaschromatography is a particularly suitable method if it is possible to measure nitrous oxide concentrations in the ppm to ppb region. For this, most frequently used gaschromatographic detectors (flame ionization detector, thermal conductivity detector) are unsuitable, whereas radiation ionization detectors can be used successfully. The investigations using detectors designed at the Central Institute for Isotopes and Radiation Research of the GDR Academy of Sciences showed that a high-temperature electron-capture detector (ECD), working at a temperatur of 250 0 C, enables the determination of traces of nitrous oxide with a detection limit of about 200 ppb, while the helium detector has a limit of 50 ppb of nitrous oxide in room air. Since the helium detector requires extremely pure carrier gas, the high-temperature ECD appears more suitable for analyzing nitrous oxide. (author)

  14. Fabrication of advanced military radiation detector sensor and performance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sin Yang

    2010-02-15

    Recently, our country is facing a continuous nuclear weapons threat. Therefore, we must have a high-level nuclear weapons protection system. The best protection against nuclear weapons is detecting their use to reduce casualties in our country to a minimum. That means, the development of a military radiation detector is a very important issue. The Korea army is using the 'PDR - 1K portable military radiation surveymeter' in NBC (Nuclear, Biological, Chemical warfare) operations. The PDR - 1K military detector can measure beta and gamma rays only but it cannot detect alpha particles. Because of its characteristics, the Korea army has weaknesses in tactical operations. The PDR - 1K sensor is based on a GM - tube sensor system. For the mechanical structure, detectors utilizing a GM-tube sensor do not work on a high - radiation battlefield and they do not carry out nuclide analysis for fixed electron signal output. In the meantime, the United States of America and Germany are using 'AN/PDR - 77' and 'SVG - 2' that were made from scintillator sensors. They have excellent physical qualities and radiation responses for military use. Also, nuclide analysis is available. Therefore, in this study we fabricated a military - grade scintillator radiation sensor that is able to detect alpha, beta, and gamma - rays to overcome PDR - 1K's weaknesses. Also, physical characteristics and radiation response evaluation for the fabricated sensors was carried out. The alpha - particle sensor and beta - ray sensor were fabricated using a ZnS(Ag) powder state scintillator, and a Saint - Gobain organic plastic scintillator BC-408 panel, respectively. The gamma ray sensor was manufactured using a 10 x 10 x 10 mm{sup 3} CsI(Tl) inorganic scintillator crystal. A detailed explanation follows. The alpha particle sensor was fabricated by using air - brushing method to Zns(Ag) powder scintillator spreading. The ZnS(Ag) layer thickness was 35 {mu}m (detection

  15. Radiation protecting clothing materials

    International Nuclear Information System (INIS)

    Mio, Kotaro; Ijiri, Yasuo.

    1986-01-01

    Purpose: To provide radiation protecting clothing materials excellent in mechanical strength, corrosion resistance, flexibility and flexing strength. Constitution: The radiation protecting clothing materials according to this invention has pure lead sheets comprising a thin pure lead foil of 50 to 150 μm and radiation resistant organic materials, for example, polyethylene with high neutron shielding effect disposed to one or both surfaces thereof. The material are excellent in the repeating bending fatigue and mechanical strength, corrosion resistance and flexibility and, accordingly, radiation protecting clothings prepared by using them along or laminating them also possess these excellent characteristics. Further, they are excellent in the handlability, particularly, durability to the repeated holding and extension, as well as are preferable in the physical movability and feeling upon putting. The clothing materials may be cut into an appropriate size, or stitched into clothings made by radiation-resistant materials. In this case, pure lead sheets are used in lamination. (Horiuchi, T.)

  16. Systems and methods for neutron detection using scintillator nano-materials

    Science.gov (United States)

    Letant, Sonia Edith; Wang, Tzu-Fang

    2016-03-08

    In one embodiment, a neutron detector includes a three dimensional matrix, having nanocomposite materials and a substantially transparent film material for suspending the nanocomposite materials, a detector coupled to the three dimensional matrix adapted for detecting a change in the nanocomposite materials, and an analyzer coupled to the detector adapted for analyzing the change detected by the detector. In another embodiment, a method for detecting neutrons includes receiving radiation from a source, converting neutrons in the radiation into alpha particles using converter material, converting the alpha particles into photons using quantum dot emitters, detecting the photons, and analyzing the photons to determine neutrons in the radiation.

  17. A gas microstrip wide angle X-ray detector for application in synchrotron radiation experiments

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Lipp, J; Mir, J A; Simmons, J E; Spill, E J; Stephenson, R; Dobson, B R; Farrow, R C; Helsby, W I; Mutikainen, R; Suni, I

    2002-01-01

    The Gas Microstrip Detector has counting rate capabilities several orders of magnitude higher than conventional wire proportional counters while providing the same (or better) energy resolution for X-rays. In addition the geometric flexibility provided by the lithographic process combined with the self-supporting properties of the substrate offers many exciting possibilities for X-ray detectors, particularly for the demanding experiments carried out on Synchrotron Radiation Sources. Using experience obtained in designing detectors for Particle Physics we have developed a detector for Wide Angle X-ray Scattering studies. The detector has a fan geometry which makes possible a gas detector with high detection efficiency, sub-millimetre spatial resolution and good energy resolution over a wide range of X-ray energy. The detector is described together with results of experiments carried out at the Daresbury Laboratory Synchrotron Radiation Source.

  18. Soft x-ray detection with diamond photoconductive detectors

    International Nuclear Information System (INIS)

    Kania, D.R.; Pan, L.; Kornblum, H.; Bell, P.; Landen, O.N.; Pianetta, P.

    1990-01-01

    Photoconductive detectors fabricated from natural lla diamonds have been used to measure the x-ray power emitted from laser produced plasmas. The detector was operated without any absorbing filters to distort the x-ray power measurement. The 5.5 eV bandgap of the detector material practically eliminates its sensitivity to scattered laser radiation thus permitting filterless operation. The detector response time or carrier life time was 90 ps. Excellent agreement was achieved between a diamond PCD and a multichannel photoemissive diode array in the measurement of radiated x-ray power and energy. 4 figs

  19. Studies of radiation hardness of MOS devices for application in a linear collider vertex detector

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Qingyu

    2008-10-17

    The proposed International Linear Collider (ILC) together with the Large Hadron Collider (LHC) at CERN serve as a combined tool to explore the mysteries of the universe: the former is a precision machine and the latter can be considered as a finding machine. The key component of the ILC is the vertex detector that should be placed as close as possible to the Interaction Point (IP) and has better radiation tolerance against the dominant electron-positron pair production background from beam-beam interactions. A new generation of MOS-type Depleted-Field-Effect Transistor (MOSDEPFET) active pixel detectors has been proposed and developed by Semiconductor Labor Munich for Physics and for extraterrestrial Physics in order to meet the requirements of the vertex detector at the ILC. Since all MOS devices are susceptible to ionizing radiation, the main topic is focused on the radiation hardness of detectors, by which a series of physical processes are analyzed: e.g. surface damage due to ionizing radiation as well as damage mechanisms and their associated radiation effects. As a consequence, the main part of this thesis consists of a large number of irradiation experiments and the corresponding discussions. Finally, radiation hardness of the detectors should be improved through a set of concluded experiences that are based on a series of analysis of the characteristic parameters using different measurement techniques. The feasibility of the MOSDEPFET-based vertex detector is, therefore, predicted at ILC. (orig.)

  20. Studies of radiation hardness of MOS devices for application in a linear collider vertex detector

    International Nuclear Information System (INIS)

    Wei, Qingyu

    2008-01-01

    The proposed International Linear Collider (ILC) together with the Large Hadron Collider (LHC) at CERN serve as a combined tool to explore the mysteries of the universe: the former is a precision machine and the latter can be considered as a finding machine. The key component of the ILC is the vertex detector that should be placed as close as possible to the Interaction Point (IP) and has better radiation tolerance against the dominant electron-positron pair production background from beam-beam interactions. A new generation of MOS-type Depleted-Field-Effect Transistor (MOSDEPFET) active pixel detectors has been proposed and developed by Semiconductor Labor Munich for Physics and for extraterrestrial Physics in order to meet the requirements of the vertex detector at the ILC. Since all MOS devices are susceptible to ionizing radiation, the main topic is focused on the radiation hardness of detectors, by which a series of physical processes are analyzed: e.g. surface damage due to ionizing radiation as well as damage mechanisms and their associated radiation effects. As a consequence, the main part of this thesis consists of a large number of irradiation experiments and the corresponding discussions. Finally, radiation hardness of the detectors should be improved through a set of concluded experiences that are based on a series of analysis of the characteristic parameters using different measurement techniques. The feasibility of the MOSDEPFET-based vertex detector is, therefore, predicted at ILC. (orig.)

  1. Cadmium telluride gamma-radiation detectors with a high energy resolution

    International Nuclear Information System (INIS)

    Alekseeva, L.A.; Dorogov, P.G.; Ivanov, V.I.; Khusainov, A.K.

    1985-01-01

    This paper considers the possibility of improving the energy resolution of cadmium telluride gamma-radiation detectors through the choice of the geometry and size of the sensitive region of the detector. The optimum ratio of the product of the mobility and lifetime for electrons to the same product for holes from the point of view of energy resolution is greater than or equal to 10 2 for a detector of spherical geometry and should be less than or equal to 10 for a cylindrical geometry and approximately 1 for a planar geometry. The optimum values of the major and minor radii of a spherical detector are calculated

  2. Advanced radiation detector development: Advanced semiconductor detector development: Development of a oom-temperature, gamma ray detector using gallium arsenide to develop an electrode detector

    International Nuclear Information System (INIS)

    Knoll, G.F.

    1995-11-01

    The advanced detector development project at the University of Michigan has completed the first full year of its current funding. Our general goals are the development of radiation detectors and spectrometers that are capable of portable room temperature operation. Over the past 12 months, we have worked primarily in the development of semiconductor spectrometers with open-quotes single carrierclose quotes response that offer the promise of room temperature operation and good energy resolution in gamma ray spectroscopy. We have also begun a small scale effort at investigating the properties of a small non-spectroscopic detector system with directional characteristics that will allow identification of the approximate direction in which gamma rays are incident. These activities have made use of the extensive clean room facilities at the University of Michigan for semiconductor device fabrication, and also the radiation measurement capabilities provided in our laboratory in the Phoenix Building on the North Campus. In addition to our laboratory based activities, Professor Knoll has also been a participant in several Department of Energy review activities held in the Forrestal Building and at the Germantown site. The most recent of these has been service on a DOE review panel chaired by Dr. Hap Lamonds that is reviewing the detector development programs supported through the Office of Arms Control and International Security

  3. Technical Note: Response measurement for select radiation detectors in magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, M., E-mail: michaelreynolds@ualberta.net [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2, Canada and Departments of Oncology and Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Rathee, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2, Canada and Department of Oncology, Medical Physics Division,University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2015-06-15

    Purpose: Dose response to applied magnetic fields for ion chambers and solid state detectors has been investigated previously for the anticipated use in linear accelerator–magnetic resonance devices. In this investigation, the authors present the measured response of selected radiation detectors when the magnetic field is applied in the same direction as the radiation beam, i.e., a longitudinal magnetic field, to verify previous simulation only data. Methods: The dose response of a PR06C ion chamber, PTW60003 diamond detector, and IBA PFD diode detector is measured in a longitudinal magnetic field. The detectors are irradiated with buildup caps and their long axes either parallel or perpendicular to the incident photon beam. In each case, the magnetic field dose response is reported as the ratio of detector signals with to that without an applied longitudinal magnetic field. The magnetic field dose response for each unique orientation as a function of magnetic field strength was then compared to the previous simulation only studies. Results: The measured dose response of each detector in longitudinal magnetic fields shows no discernable response up to near 0.21 T. This result was expected and matches the previously published simulation only results, showing no appreciable dose response with magnetic field. Conclusions: Low field longitudinal magnetic fields have been shown to have little or no effect on the dose response of the detectors investigated and further lend credibility to previous simulation only studies.

  4. Estimation of Cosmic Induced Contamination in Ultra-low Background Detector Materials

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Berguson, Timothy J.; Greene, Austen T.

    2012-08-01

    Executive Summary This document presents the result of investigating a way to reliably determine cosmic induced backgrounds for ultra-low background materials. In particular, it focuses on those radioisotopes produced by the interactions with cosmic ray particles in the detector materials that act as a background for experiments looking for neutrinoless double beta decay. This investigation is motivated by the desire to determine background contributions from cosmic ray activation of the electroformed copper that is being used in the construction of the MAJORANA DEMONSTRATOR. The most important radioisotope produced in copper that contributes to the background budget is 60Co, which has the potential to deposit energy in the region of interest of this experiment. Cobalt-60 is produced via cosmic ray neutron collisions in the copper. This investigation aims to provide a method for determining whether or not the copper has been exposed to cosmic radiation beyond the threshold which the Majorana Project has established as the maximum exposure. This threshold is set by the Project as the expected contribution of this source of background to the overall background budget. One way to estimate cosmic ray neutron exposure of materials on the surface of the Earth is to relate it to the cosmic ray muon exposure. Muons are minimum-ionizing particles and the available technologies to detect muons are easier to implement than those to detect neutrons. We present the results of using a portable, ruggedized muon detector, the µ-Witness made by our research group, for determination of muon exposure of materials for the MAJORANA DEMONSTRATOR. From the muon flux measurement, this report presents a method to estimate equivalent sea-level exposure, and then infer the neutron exposure of the tracked material and thus the cosmogenic activation of the copper. This report combines measurements of the muon flux taken by the µ-Witness detector with Geant4 simulations in order to assure our

  5. Radiation hard 3D diamond sensors for vertex detectors at HL-LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00336619; Quadt, Arnulf; Grosse-Knetter, Jörn; Weingarten, Jens

    Diamond is a good candidate to replace silicon as sensor material in the innermost layer of a tracking detector at HL-LHC, due to its high radiation tolerance. After particle fluences of $10^{16}\\,{\\rm protons/cm^2}$, diamond sensors are expected to achieve a higher signal to noise ratio than silicon. In order to use low grade polycrystalline diamonds as sensors, electrodes inside the diamond bulk, so called 3D electrodes, are produced. Typically, this kind of diamond material has a lower charge collection distance (CCD) than higher grade diamond, which results in a decreased signal amplitude. With 3D electrodes it is possible to achieve full charge collection even in samples with low CCDs by decoupling the spacing of the electrodes from the thickness of the diamond bulk. The electrodes are produced using a femtosecond laser, which changes the phase of the diamond material. The phase changed material is conductive and identified as nanocrystalline graphite using Raman spectroscopy. Due to a crater like struct...

  6. Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

    CERN Document Server

    Moll, Michael; Lindström, G

    2000-01-01

    We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2*10/sup 14/ to 9*10/sup 17/ cm/sup -3/ have been irradiated with fast neutrons up to a fluence of 2*10/sup 15/ cm/sup -2/. Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10601130f the initial doping concentration for [O/sub i/]=9*10/sup 17/ cm/sup -3/, while for normal detector grade material with [O/sub i/] below 5*10/sup 16/ cm /sup -3/ that value is 60-90Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentratio...

  7. Non-contact radiation thickness gauge

    International Nuclear Information System (INIS)

    Tsujii, T.; Okino, T.

    1983-01-01

    A noncontact thickness gauge system for measuring the thickness of a material comprising a source of radiation, a detector for detecting the amount of radiation transmitted through the material which is a function of the absorptance and thickness of the material, a memory for storing the output signals of the detector and curve-defining parameters for a plurality of quadratic calibration curves which correspond to respective thickness ranges, and a processor for processing the signals and curve defining parameters to determine the thickness of the material. Measurements are made after precalibration to obtain calibration curves and these are stored in the memory, providing signals representative of a nominal thickness and an alloy compensation coefficient for the material. The calibration curve corresponding to a particular thickness range is selected and the curve compensated for drift; the material is inserted into the radiation path and the detector output signal processed with the compensated calibration curve to determine the thickness of the material. (author)

  8. Growth, characterization and properties of CVD diamond films for applications as radiation detectors

    International Nuclear Information System (INIS)

    Sciorti, S.

    1999-01-01

    The aim of the work is to give a picture of the current state of the art of CVD (chemical vapour deposition) diamond. The interest is due to the capability to grow over large areas a material with physical properties suitable for an impressive number of applications. The authors focuses on the potential of diamond as a radiation detector and gets into details of the huge field that extends from the thermochemistry of the deposition process to the test of a diamond-based tracker with a fast readout electronics

  9. The transition radiation detector of the PAMELA space mission

    Science.gov (United States)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; de Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2004-04-01

    PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta.

  10. The transition radiation detector of the PAMELA space mission

    International Nuclear Information System (INIS)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; De Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2004-01-01

    PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta

  11. Regulation No. 0-31 on handling of radiation flaw-detectors

    International Nuclear Information System (INIS)

    1975-01-01

    The regulation contains mandatory design, commissioning, and operational requirements for laboratories using flaw-detectors emitting ionizing radiation; also, design, manufacturing, and operational requirements for the production of any type of X-ray or gamma-ray flaw-detectors. Laboratories carrying out non-destructive testing are either stationary or mobile. Conceptual and operating designs are elaborated, including the building and the laboratory lay-outs, the mains, water supply, and sewerage system technological lay-out, explanatory comments, and a lay-out of the shielding equipment. Approbated designs are implemented, and the laboratories commissioned to representatives of the State Sanitary Inspectorate. Licences are issued by the Ministry of Public Health (MPH) and the Committee on Peaceful Uses of Atomic Energy (CPUAE). Any flaw-detector has to conform to the Bulgarian State Standards and be coordinated with the MPH, the CPUAE, and the Central Laboratory for Nuclear Flaw-Detection (CLNFD). The laboratories are required to have operational instructions, an emergency plan, and to keep technological and dosimetric records. The latter are provided and processed by the relevant service at the Research Institute of Radiobiology and Radiation Hygiene. For operations involving of flaw-detectors, presence of at least two workers is required. (G.G.)

  12. Application of gamma radiation backscattering in determining density and Zsub(eff) of scattering material Monte Carlo optimization of configuration

    International Nuclear Information System (INIS)

    Cechak, T.

    1982-01-01

    Applying Gardner's method of double evaluation one detector should be positioned such that its response should be independent of the material density and the second detector should be positioned so as to maximize changes in response due to density changes. The experimental scanning for optimal energy is extremely time demanding. A program was written based on the Monte Carlo method which solves the problem of error magnitude in case the computation of gamma radiation backscattering neglects multiply scattered photons, the problem of how this error depends on the atomic number of the scattering material as well as the problem of whether the representation of individual scatterings in the spectrum of backscattered photons depends on the positioning of the detector. 42 detectors, 8 types of material and 10 different density values were considered. The computed dependences are given graphically. (M.D.)

  13. Development of an X-ray detector using photodiodes

    International Nuclear Information System (INIS)

    Gonzalez G, J.; Azorin V, J. C.; Sosa A, M. A.; Ceron, P.

    2016-10-01

    Currently the radiation detectors for medical applications are very high value in the market and are difficult to access as training material. In the Sciences and Engineering Division of the Guanajuato University (Mexico) investigations are carried out related to ionizing radiations, especially with X-rays. To overcome the lack of materials has had to resort to borrowing equipment from other institutions, so its use and availability are intermittent. For these reasons is proposed to design and implement an X-ray detector for the use of the work group and the University. This work aims to build an X-ray semiconductor detector using inexpensive and affordable materials, is also proposed the use of a photodiode sensor and an Arduino analog-digital card and a LCD display showing the data. (Author)

  14. Determination of the exhalation rate of radon and thoron from building materials by detectors Cr-39

    International Nuclear Information System (INIS)

    Vasidov, A.

    2005-01-01

    Full text: The building materials (BM) such as granite, bricks, sand, cement etc., contain uranium and thorium in various amounts. Therefore the knowledge of true value exhalation rate of Rn and Tn from BM represents scientific and practical interest in environmental radiation protection. In present work, we have used calibrated plastic cups with two detectors Cr-39. The detected surface of the cup is situated in perpendicular position surface BM and were exposed for 20-30 days. The first detector fixed the bottom on distance from surface of BM and records alpha particles from Rn-222 only. The second detector records alpha particles of the thoron and radon. After exposition, the detectors chemically etched and analyzed. The values of the exhalation rate per unit area of the granite, concrete, fired and unfired bricks, sand, cement, alabaster varied 0.091 - 0.1 Bq m -2 h -1 for the radon, 200 - 5800 Bq m -2 h - 1 for the thoron, accordingly

  15. Scintillation characteristics of phosphich-detector for detection of beta- and gamma-radiations

    CERN Document Server

    Ananenko, A A; Gavrilyuk, V

    2002-01-01

    The results of the study on the influence of individual peculiarities of the compound scintillation detector structure on the value and stability of the light yield by the gamma- and beta-radiation combined registration are presented. The phosphich detector is manufactured from the sodium iodide monocrystal, activated by thallium, and the scintillation plastic on the polystyrol basis. The comparison of the experimental results with the mathematical modeling data revealed certain regularities of the process of forming the phosphich detector light signal. The recommendations are worked out by means whereof the following characteristics of the scintillation unit: the light yield and its stability, amplitude resolution and the peak-to-valley ratio by the gamma- and beta-radiation registration were improved

  16. Status of diamond particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Krammer, M.; Adam, W.; Friedl, M.; Hrubec, J.; Pernegger, H.; Pernicka, M. [Institut fuer Hochenergiephysik der Oesterr. Akademie d. Wissenschaften, Nikolsdorferg. 18, A-1050 Vienna (Austria); Bauer, C. [MPI fuer Kernphysik, D-69029 Heidelberg (Germany); Berdermann, E.; Stelzer, H. [GSI, Darmstadt (Germany); Bogani, F. [LENS, Florence (Italy); Borchi, E.; Bruzzi, M.; Sciortino, S. [University of Florence, Florence (Italy); Colledani, C.; Dulinski, W.; Husson, D.; LeNormand, F.; Riester, G.L.; Turchetta, R. [LEPSI, CRN Strasbourg (France); Conway, J.; Fish, D.; Schnetzer, S.; Stone, R.; Tesarek, R.; Thomson, G.B.; Walsh, A.M. [Rutgers University, Piscataway, NJ (United States); Dabrowski, W.; Kaplon, J.; Meier, D.; Roe, S.; Rudge, A.; Wedenig, R.; Weilhammer, P. [CERN, CH-1211 Geneva (Switzerland); Delpierre, P.; Hallewell, G. [CPPM, Marseille (France); Deneuville, A.; Cheeraert, E. [LEPES, Grenoble (France); Eijk, B.V.; Hartjes, F. [NIKHEF, Amsterdam (Netherlands); Fallou, A. [CPPM, Marseille (France); Foulon, F. [Centre d' Etudes de Saclay, 91191 Gif-Sur-Yvette (France); Gan, K.K.; Kagan, H.; Kass, R.; Trawick, M.; Zoeller, M. [The Ohio State University, Columbus, OH (United States); Grigoriev, E.; Knoepfle, K.T. [MPI fuer Kernphysik, D-69029 Heidelberg (Germany); Hall-Wilton, R. [Bristol University, Bristol (United Kingdom); Han, S.; Ziock, H. [Los Alamos National Laboratory, Research Division, Los Alamos, NM (United States); Kania, D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Manfredi, P.F.; Re, V.; Speziali, V. [Universita di Pavia, Dipartimento di Elettronica, 27100 Pavia (Italy); Mishina, M. [FNAL, Batavia, IL (United States); Pan, L.S. [Sandia National Laboratory, Albuquerque, NM (United States); Roff, D.; Tapper, R.J. [Bristol University, Bristol (United Kingdom); Trischuk, W. [University of Toronto, Toronto (Canada)

    1998-11-21

    To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  17. Status of diamond particle detectors

    International Nuclear Information System (INIS)

    Krammer, M.; Adam, W.; Friedl, M.; Hrubec, J.; Pernegger, H.; Pernicka, M.; Bauer, C.; Berdermann, E.; Stelzer, H.; Bogani, F.; Borchi, E.; Bruzzi, M.; Sciortino, S.; Colledani, C.; Dulinski, W.; Husson, D.; LeNormand, F.; Riester, G.L.; Turchetta, R.; Conway, J.; Fish, D.; Schnetzer, S.; Stone, R.; Tesarek, R.; Thomson, G.B.; Walsh, A.M.; Dabrowski, W.; Kaplon, J.; Meier, D.; Roe, S.; Rudge, A.; Wedenig, R.; Weilhammer, P.; Delpierre, P.; Hallewell, G.; Deneuville, A.; Cheeraert, E.; Eijk, B.V.; Hartjes, F.; Fallou, A.; Foulon, F.; Gan, K.K.; Kagan, H.; Kass, R.; Trawick, M.; Zoeller, M.; Grigoriev, E.; Knoepfle, K.T.; Hall-Wilton, R.; Han, S.; Ziock, H.; Kania, D.; Manfredi, P.F.; Re, V.; Speziali, V.; Mishina, M.; Pan, L.S.; Roff, D.; Tapper, R.J.; Trischuk, W.

    1998-01-01

    To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. RID-41 gamma flaw detector

    International Nuclear Information System (INIS)

    Glebov, V.N.; Zubkov, V.S.; Majorov, A.N.; Murashev, A.I.; Firstov, V.G.; Yampol'skij, V.V.; Goncharov, V.I.; Sakhanov, A.S.

    1978-01-01

    The design is described and the main characteristics are given of a universal stationary hose-type gamma flow detector with a 60 Co source from 3O to 4g0 Ci for high-productive control of thick-walled products from steel and other materials. The principal units of the instrument are a radiation head, a control panel, and a charge-exchange container. The flaw detector may be used both in shield chambers and in shop or mounting conditions on complying with due requirements of radiation protection. The high activity of the source at relatively small dimensions of its active part ensures good detection of defects. The high radioscopy rate permits to use the flaw detector in conditions of increased background radiation, e.g. during routine repairs and inspections at nuclear power plants. The instrument may also be used in radiometric complexes, and produces a considerable economic effect. This flaw-detector corresponds to ISO and IAEA requirements and may be delivered for export

  19. General specifications for silicon semiconductors for use in radiation dosimetry

    International Nuclear Information System (INIS)

    Rikner, G.; Grusell, E.

    1987-01-01

    Silicon semiconductor detectors used in radiation dosimetry have different properties, just as e.g. ionisation chambers, affecting the interaction of radiation with matter in the vicinity of the sensitive volume of the detector, e.g. wall materials, and also the collection of the charges liberated in the detector by the radiation. The charge collection depends on impurities, lattice imperfections and other properties of the semiconductor crystal. In this paper the relevant parameters of a silicon semiconductor detector intended for dosimetry are reviewed. The influence of doping material, doping level, various effects of radiation damage, mechanical construction, detector size, statistical noise and connection to the electrometer are discussed. (author)

  20. The iQID camera: An ionizing-radiation quantum imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Brian W., E-mail: brian.miller@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); College of Optical Sciences, The University of Arizona, Tucson, AZ 85719 (United States); Gregory, Stephanie J.; Fuller, Erin S. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Barrett, Harrison H.; Bradford Barber, H.; Furenlid, Lars R. [Center for Gamma-Ray Imaging, The University of Arizona, Tucson, AZ 85719 (United States); College of Optical Sciences, The University of Arizona, Tucson, AZ 85719 (United States)

    2014-12-11

    We have developed and tested a novel, ionizing-radiation Quantum Imaging Detector (iQID). This scintillation-based detector was originally developed as a high-resolution gamma-ray imager, called BazookaSPECT, for use in single-photon emission computed tomography (SPECT). Recently, we have investigated the detector's response and imaging potential with other forms of ionizing radiation including alpha, neutron, beta, and fission fragment particles. The confirmed response to this broad range of ionizing radiation has prompted its new title. The principle operation of the iQID camera involves coupling a scintillator to an image intensifier. The scintillation light generated by particle interactions is optically amplified by the intensifier and then re-imaged onto a CCD/CMOS camera sensor. The intensifier provides sufficient optical gain that practically any CCD/CMOS camera can be used to image ionizing radiation. The spatial location and energy of individual particles are estimated on an event-by-event basis in real time using image analysis algorithms on high-performance graphics processing hardware. Distinguishing features of the iQID camera include portability, large active areas, excellent detection efficiency for charged particles, and high spatial resolution (tens of microns). Although modest, iQID has energy resolution that is sufficient to discriminate between particles. Additionally, spatial features of individual events can be used for particle discrimination. An important iQID imaging application that has recently been developed is real-time, single-particle digital autoradiography. We present the latest results and discuss potential applications.

  1. CVD Diamond Sensors In Detectors For High Energy Physics

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00334150; Trischuk, William

    At the end of the next decade an upgrade of the Large Hadron Collider (LHC) to High Luminosity LHC (HL-LHC) is planned which requires the development of new radiation tolerant sensor technology. Diamond is an interesting material for use as a particle detector in high radiation environments. The large band gap ($5.47\\,\\text{eV}$) and the large displacement energy suggest that diamond is a radiation tolerant detector material. In this Thesis the capability of Chemical Vapor Deposition (CVD) diamond as such a sensor technology is investigated. The radiation damage constant for $800\\,\\text{MeV}$ protons is measured using single crystalline CVD (scCVD) and polycrystalline CVD (pCVD) diamonds irradiated to particle fluences up to $12 \\times 10^{15}\\,\\text{p/cm}^2$. In addition the signal response of a pCVD diamond detector after an irradiation to $12 \\times 10^{15}\\,\\text{p/cm}^2$ is investigated to determine if such a detector can be operated efficiently in the expected HL-LHC environment. By using electrodes em...

  2. Radiation monitoring and beam dump system of the OPAL silicon microvertex detector

    CERN Document Server

    Braibant, S

    1997-01-01

    The OPAL microvertex silicon detector radiation monitoring and beam dump system is described. This system was designed and implemented in order to measure the radiation dose received at every beam crossing and to induce a fast beam dump if the radiation dose exceeds a given threshold.

  3. Study on the energy dependence of gamma radiation detectors for 137Cs and 60Co

    International Nuclear Information System (INIS)

    Nonato, Fernanda B.C.; Diniz, Raphael E.; Carvalho, Valdir S.; Vivolo, Vitor; Caldas, Linda V.E.

    2009-01-01

    38 Geiger-Mueller radiation detectors and 9 ionization chambers were calibrated, viewing to study the energy dependence of the monitor response for gamma radiation fields ( 137 Cs and 60 Co). The results were considered satisfactory only for ionization chambers and for some Geiger-Mueller detectors

  4. Exploiting different active silicon detectors in the International Space Station: ALTEA and DOSTEL galactic cosmic radiation (GCR) measurements

    Science.gov (United States)

    Narici, Livo; Berger, Thomas; Burmeister, Sönke; Di Fino, Luca; Rizzo, Alessandro; Matthiä, Daniel; Reitz, Günther

    2017-08-01

    The solar system exploration by humans requires to successfully deal with the radiation exposition issue. The scientific aspect of this issue is twofold: knowing the radiation environment the astronauts are going to face and linking radiation exposure to health risks. Here we focus on the first issue. It is generally agreed that the final tool to describe the radiation environment in a space habitat will be a model featuring the needed amount of details to perform a meaningful risk assessment. The model should also take into account the shield changes due to the movement of materials inside the habitat, which in turn produce changes in the radiation environment. This model will have to undergo a final validation with a radiation field of similar complexity. The International Space Station (ISS) is a space habitat that features a radiation environment inside which is similar to what will be found in habitats in deep space, if we use measurements acquired only during high latitude passages (where the effects of the Earth magnetic field are reduced). Active detectors, providing time information, that can easily select data from different orbital sections, are the ones best fulfilling the requirements for these kinds of measurements. The exploitation of the radiation measurements performed in the ISS by all the available instruments is therefore mandatory to provide the largest possible database to the scientific community, to be merged with detailed Computer Aided Design (CAD) models, in the quest for a full model validation. While some efforts in comparing results from multiple active detectors have been attempted, a thorough study of a procedure to merge data in a single data matrix in order to provide the best validation set for radiation environment models has never been attempted. The aim of this paper is to provide such a procedure, to apply it to two of the most performing active detector systems in the ISS: the Anomalous Long Term Effects in Astronauts (ALTEA

  5. Study of a transition radiation detector for the DO experiment at FNAL

    International Nuclear Information System (INIS)

    Feinstein, F.

    1988-06-01

    The DZero experiment will study proton-antiproton collisions at 1.8 TeV in the center of mass produced at Fermi National Accelerator Laboratory (USA). The main features of the detector are an excellent hermetical calorimeter and a very good identification of muons and electrons. The Transition Radiation Detector contributes to electron/jet discrimination. Transition radiation is emitted when a charge particle crosses the interface between two media of different refraction indices. A N foils radiator produces about N/137 soft X rays when the Lorentz factor gamma of the particle is greater than a threshold of the order of 1000. The radiated energy saturates when gamma goes to infinity. These properties allow to separate electrons from pions until 140 GeV. This study presents the results of a test on a 5 GeV electron and pion beam of a prototype of chamber and of three radiators made of lithium foils, polypropylene foils, and polyethylene fibers. The detector response to pions and electrons is compared to theoretical predictions. Different statistical methods of electron/pion separation are compared on the experimental data. A method has been performed using likelihood functions which obtains a pion rejection greater than 50 for an electron efficiency of 90%. The performances are compared to those of other TRDs [fr

  6. Radiation-sensitive material and method of recording information upon radiation-sensitive material

    International Nuclear Information System (INIS)

    Petrov, V.V.; Krjuchin, A.A.

    1981-01-01

    The invention can be employed for recording binary information in memory units of electronic computers, in video-recording equipment, laser recording devices and other recording means. The proposed radiation-sensitive material comprises a metallic layer made of silver, or copper, or nickel, or thallium, or alloy thereof, an inorganic material layer made of arsenic chalcogenide, or antimony chalcogenide, or bismuth chalcogenide, and a separation layer disposed between the metallic layer and the inorganic material layer made of a material which is inert relative to said layers, which separation layer has a thickness sufficient for preventing interaction between the metallic layer and the inorganic material layer when the radiation-sensitive materials is exposed to electromagnetic or corpuscular radiation having a power density lower than a threshold value required for the breakdown of the separation layer in the area exposed to radiation. The separation layer can be made from As, Sb, Si or Ge or their oxides, metallic oxides of e.g. Al, Ti, V or Fe, or from polyorganosiloxane films. (author)

  7. Principles of nuclear radiation detection

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Poston, J.W.

    1985-01-01

    This book covers the transistorization of equipment and provides an introduction into practice of semiconductor and thermoluminescent detectors. It discusses the principles of radiation detectors most widely used in nuclear technology, medical practice and radiation protection. It stresses the alternative detectors available and discusses practical considerations in choosing and setting up detector systems for actual use. Traditional materials, including semiconductors, TLD's and modern data handling facilities are covered

  8. The ALICE Transition Radiation Detector: Construction, operation, and performance

    Science.gov (United States)

    Alice Collaboration

    2018-02-01

    The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/ c in p-Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both for jet, light nuclei, and electron selection.

  9. Germanium junction detectors. Theoretical and practical factors governing their use in radiation spectrometry

    International Nuclear Information System (INIS)

    Hors, M.; Philis, C.

    1967-01-01

    Semi-conductor detectors have recently greatly increased the possibilities available to nuclear spectroscopists for the study of α, β and γ radiations. Their use in radio-chemistry has encouraged us to study their principle, their mechanism and also the conditions under which they can be used. The first part, which is theoretical, consists of a summary of what should be known concerning the best use of junction detectors, in particular Ge (Li) detectors. The second part, which is experimental, summarizes the laboratory work carried out over a period of one year on Ge (Li) detectors. Stress is laid on the possibilities presented by the use of these detectors as photo-electric spectrometers, and also on the precautions required. Amongst the numerous results presented, the resolution of 2.52 keV obtained for the γ radiation of 145.5 keV for 141 Ce may be particularly noted. (authors) [fr

  10. The ATLAS Pixel Detector

    CERN Document Server

    Huegging, Fabian

    2006-06-26

    The contruction of the ATLAS Pixel Detector which is the innermost layer of the ATLAS tracking system is prgressing well. Because the pixel detector will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability for all parts, combined with a low material budget. The final detector layout, new results from production modules and the status of assembly are presented.

  11. Radiation source reconstruction with known geometry and materials using the adjoint

    International Nuclear Information System (INIS)

    Hykes, Joshua M.; Azmy, Yousry Y.

    2011-01-01

    We present a method to estimate an unknown isotropic source distribution, in space and energy, using detector measurements when the geometry and material composition are known. The estimated source distribution minimizes the difference between the measured and computed responses of detectors located at a selected number of points within the domain. In typical methods, a forward flux calculation is performed for each source guess in an iterative process. In contrast, we use the adjoint flux to compute the responses. Potential applications of the proposed method include determining the distribution of radio-contaminants following a nuclear event, monitoring the flow of radioactive fluids in pipes to determine hold-up locations, and retroactive reconstruction of radiation fields using workers' detectors' readings. After presenting the method, we describe a numerical test problem to demonstrate the preliminary viability of the method. As expected, using the adjoint flux reduces the number of transport solves to be proportional to the number of detector measurements, in contrast to methods using the forward flux that require a typically larger number proportional to the number of spatial mesh cells. (author)

  12. Double gated-integrator for shaping nuclear radiation detector signals

    International Nuclear Information System (INIS)

    Gal, J.

    2001-01-01

    A new shaper, the double gated-integrator, for shaping nuclear radiation detector signals is investigated both theoretically and experimentally. The double gated-integrator consists of a pre-filter and two cascaded gated integrators. Two kinds of pre-filters were considered: a rectangular one and an exponential one. The results of the theoretical calculation show that the best figure of demerit for the double gated-integrator with exponential pre-filter is 1.016. This means that its noise to signal ratio is only 1.6% worse than that it is for infinite cusp shaping. The practical realization of the exponential pre-filter and that of the double gated integrator, both in analogue and in digital way, is very simple. Therefore, the double gated-integrator with exponential pre-filter could be a promising solution for shaping nuclear radiation detector signals

  13. LET spectrometry with track etch detectors-Use in high-energy radiation fields

    International Nuclear Information System (INIS)

    Jadrnickova, I.; Spurny, F.

    2008-01-01

    For assessing the risk from ionizing radiation it is necessary to know not only the absorbed dose but also the quality of the radiation; radiation quality is connected with the physical quantity linear energy transfer (LET). One of the methods of determination of LET is based on chemically etched track detectors. This contribution concerns with a spectrometer of LET based on the track detectors and discusses some results obtained at: ·high-energy radiation reference field created at the SPS accelerator at CERN; and ·onboard of International Space Station where track-etch based LET spectrometer has been exposed 273 days during 'Matrjoshka - R' experiment. Results obtained are compared with the results of studies at some lower-energy neutron sources; some conclusions on the registrability of neutrons and the ability of this spectrometer to determine dose equivalent in high-energy radiation fields are formulated

  14. Low-cost cadmium zinc telluride radiation detectors based on electron-transport-only designs

    International Nuclear Information System (INIS)

    Brunett, B.A.; Lund, J.C.; Van Scyoc, J.M.; Hilton, N.R.; Lee, E.Y.; James, R.B.

    1999-01-01

    The goal of this project was to utilize a novel device design to build a compact, high resolution, room temperature operated semiconductor gamma ray sensor. This sensor was constructed from a cadmium zinc telluride (CZT) crystal. It was able to both detect total radiation intensity and perform spectroscopy on the detected radiation. CZT detectors produced today have excellent electron charge carrier collection, but suffer from poor hole collection. For conventional gamma-ray spectrometers, both the electrons and holes must be collected with high efficiency to preserve energy resolution. The requirement to collect the hole carriers, which have relatively low lifetimes, limits the efficiency and performance of existing experimental devices. By implementing novel device designs such that the devices rely only on the electron signal for energy information, the sensitivity of the sensors for detecting radiation can be increased substantially. In this report the authors describe a project to develop a new type of electron-only CZT detector. They report on their successful efforts to design, implement and test these new radiation detectors. In addition to the design and construction of the sensors the authors also report, in considerable detail, on the electrical characteristics of the CZT crystals used to make their detectors

  15. Practical prototype of a cluster-counting transition radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Fabjan, C W; Willis, W [European Organization for Nuclear Research, Geneva (Switzerland); Gavrilenko, I; Maiburov, S; Shmeleva, A; Vasiliev, P [AN SSSR, Moscow. Fizicheskij Inst.; Chernyatin, V; Dolgoshein, B; Kantserov, V; Nevski, P [Moskovskij Inzhenerno-Fizicheskij Inst. (USSR)

    1981-06-15

    A transition radiation detector using a method of cluster counting measurements has been tested. The performance is considerably better than with the usual method of total charge measurements, as well as offering advantages in simplicity of construction and operation.

  16. Crystal growth and characterization of europium doped lithium strontium iodide scintillator as an ionizing radiation detector

    Science.gov (United States)

    Uba, Samuel

    High performance detectors used in the detection of ionizing radiation is critical to nuclear nonproliferation applications and other radiation detectors applications. In this research we grew and tested Europium doped Lithium Strontium Iodide compound. A mixture of lithium iodide, strontium iodide and europium iodide was used as the starting materials for this research. Congruent melting and freezing temperature of the synthesized compound was determined by differential scanning calorimetry (DSC) using a Setaram Labsys Evo DSC-DTA instrument. The melting temperatures were recorded at 390.35°C, 407.59°C and freezing temperature was recorded at 322.84°C from a graph of heat flow plotted against temperature. The synthesized material was used as the charge for the vertical Bridgeman growth, and a 6.5 cm and 7.7cm length boule were grown in a multi-zone transparent Mullen furnace. A scintillating detector of thickness 2.53mm was fabricated by mechanical lapping in mineral oil, and scintillating response and timing were obtained to a cesium source using CS-137 isotope. An energy resolution (FWHM over peak position) of 12.1% was observed for the 662keV full absorption peak. Optical absorption in the UV-Vis wavelength range was recorded for the grown crystal using a U-2900 UV/VIS Spectrophotometer. Absorption peaks were recorded at 194nm, 273nm, and 344nm from the absorbance spectrum, various optical parameters such as absorption coefficient, extinction coefficient, refractive index, and optical loss were derived. The optical band gap energy was calculated using Tauc relation expression at 1.79eV.

  17. Nano structural anodes for radiation detectors

    Science.gov (United States)

    Cordaro, Joseph V.; Serkiz, Steven M.; McWhorter, Christopher S.; Sexton, Lindsay T.; Retterer, Scott T.

    2015-07-07

    Anodes for proportional radiation counters and a process of making the anodes is provided. The nano-sized anodes when present within an anode array provide: significantly higher detection efficiencies due to the inherently higher electric field, are amenable to miniaturization, have low power requirements, and exhibit a small electromagnetic field signal. The nano-sized anodes with the incorporation of neutron absorbing elements (e.g., .sup.10B) allow the use of neutron detectors that do not use .sup.3He.

  18. Responses of diode detectors to radiation beams from teletherapy machines

    International Nuclear Information System (INIS)

    Malinda, Lora; Nasukha

    2003-01-01

    Responses of diode detectors to radiation beams from teletherapy machines. It has been carried out responses to two sets of diode detector by using the beams of teletherapy Co-60 and medical linear accelerator. Each set of consist of 8 diode detectors was irradiated by using gamma beams from teletherapy Co-60 machines and 6 MV and 10 MV foron beams from medical linear accelerator and 6.9.12.16. and 20 MeV electron beams from medical linear accelerator. The detectors were positioned on the phantom circularly and radially and electronic equilibrium condition for all type and energy beams. It was found that every detectors had own individual response and it is not to be uniformity, since the fluctuation in between 16.6 % to 30.9 %. All detectors responses are linear to gamma and foron beams, and also for energy above 6 MeV for electron beams. Nonlinearity response occurs for 6 MeV electron beam, it is probably from the assumption of electronic equilibrium

  19. The Development of a Hybrid-Type Radiation Detector with SiC for a Reactor Robot

    International Nuclear Information System (INIS)

    Lee, Nam Ho; Cho, Jai Wan; Kim, Seung Ho

    2005-01-01

    For a robot working in a harsh environment such as a nuclear reactor environment or a space environment, requirements of on-board radiation detectors are not the same as those for environments around human. SiC devices with the wide band-gap are less dependent on temperature than Si counterparts and the can be the better candidate for the high radiation environment. With this background, radiation performance of a commercial SiC detector in a Co-60 gamma-ray environment has been evaluated. In addition to the SiC detector, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) detector has been incorporated as a backup. With this MOSFET sensor the dosimeter can keep its radiation exposure history even with loss of power. It is not only a redundant feature but also a diverse feature. The dosimetry module can be attached to mobile robot for high radiation environment was developed. This module has both SiC diode and pMOSFET mentioned above. The monitoring program which receives the radiation information from them and gives out the alarm signal when the difference of the two values from them is over the preset level was constructed. Because both the SiC pulse-type detector and the MOSFET dosimeter are small and light weight, they can be easily accommodated on a small printcircuit board for a tight space on a robot arm or for a small spacecraft

  20. Radiation studied on the internet. On-line radiation teaching materials

    International Nuclear Information System (INIS)

    Inoue, Hiroyoshi; Kagoshima, Mayumi; Yamasaki, Mariko

    2005-01-01

    In order to facilitate scientific understanding of radiation in Japan where social understanding has been already progressed, we developed Internet radiation teaching materials that can be utilized as off-school teaching materials or supplementary materials. The teaching materials of ''atomic structure and radiation'' and ''medical treatment and radiation'' were tried for 160 high school students and 59 junior high school students, respectively. More than 70% of the student answered that these teaching materials were effective when they understand radiation. (author)

  1. A program in detector development for the US synchrotron radiation community

    International Nuclear Information System (INIS)

    Thompson, A.; Mills, D.; Naday, S.; Gruner, S.; Siddons, P.; Arthur, J.; Wehlitz, R.; Padmore, H.

    2001-01-01

    There is a clear gulf between the capabilities of modern synchrotrons to deliver high photon fluxes, and the capabilities of detectors to measure the resulting photon, electron or ion signals. While a huge investment has been made in storage ring technology, there has not to date been a commensurate investment in detector systems. With appropriate detector technology, gains in data rates could be 3 to 4 orders of magnitude in some cases. The US community working in detector technology is under-funded and fragmented and works without the long term funding commitment required for development of the most advanced detector systems. It is becoming apparent that the US is falling behind its international competitors in provision of state-of-the-art detector technology for cutting edge synchrotron radiation based experiments

  2. A transition radiation detector which features accurate tracking and dE/dx particle identification

    International Nuclear Information System (INIS)

    O'Brien, E.; Lissauer, D.; McCorkle, S.; Polychronakos, V.; Takai, H.; Chi, C.Y.; Nagamiya, S.; Sippach, W.; Toy, M.; Wang, D.; Wang, Y.F.; Wiggins, C.; Willis, W.; Cherniatin, V.; Dolgoshein, B.; Bennett, M.; Chikanian, A.; Kumar, S.; Mitchell, J.T.; Pope, K.

    1991-01-01

    We describe the results of a test run involving a Transition Radiation Detector that can both distinguish electrons from pions with momenta greater than 0.7 GeV/c and simultaneously track particles passing through the detector. The particle identification is accomplished through a combination of the detection of Transition Radiation from the electron and the differences in electron and pion energy loss (dE/dx) in the detector. The dE/dx particle separation is most efficient below 2 GeV/c while particle ID utilizing Transition Radiation is effective above 1.5 GeV/c. Combined, the electron-pion separation is better than 5 x l0 2 . The single-wire, track-position resolution for the TRD is ∼230μm

  3. Thermally stimulated investigations on diamond X-Ray detectors

    International Nuclear Information System (INIS)

    Tromson, D.; Bergonzo, P.; Brambilla, A.; Mer, C.; Foulon, F.; Amosov, V.N.

    1999-01-01

    Intrinsic diamond material is increasingly used for the fabrication of radiation detectors. However, the presence of inherent defects has a strong impact on the detector characteristics such as the time dependent stability of the detection signal. In order to draw better insights into this effect, comparative investigations of the X-ray responses with thermally stimulated current (TSC) measurements were carried out on natural diamond detectors. TSC revealed the presence of four peaks or shoulders on natural samples in the 200 to 500 K domain. Three energy levels were identified at about 0.7, 0.71 and 0.95 eV. Time dependent X-ray detector sensitivity was investigated for various initial conditions. The results give evidence of the improvement of the detection properties after having filled traps in the material by X-ray irradiation. The comparison between the X-ray response and the TSC spectra indicate that trapping levels emptied at room temperature appear to significantly affect the performance of radiation detectors. (authors)

  4. 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.

  5. Development, simulation and test of transition radiation detector prototypes for the compressed baryonic matter experiment at the facility for antiproton and ion research

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, Cyrano S.H.

    2014-07-01

    The focus of this thesis is the development of a Transition Radiation Detector (TRD) for the Compressed Baryonic Matter (CBM) experiment at FAIR. The TRD sub-detector will contribute to the global particle identification and track reconstruction of charged particles. The technical design goal for the TRD is to identify 90% electrons with a maximum pion contamination of 1%. The TRD and Ring Image CHerenkov (RICH) detector should reach a common pion rejection of 10{sup 4}, in order to measure charmonium and low-mass vector mesons. The position resolution should be between 200 and 300 μm in the anode wire direction. The most demanding aspect of the CBM TRD design is the high interaction rate of up to 10{sup 7} Hz resulting in a charged particle rate of up to 100 kHz/cm{sup 2} in the central part of the detector planes at SIS300 conditions. It is crucial to find the optimal radiator detector combination with a minimum material budget to limit scattering and background due to conversions and at the same time reach a sufficient pion rejection and position resolution. In this thesis it is confirmed that a Multi-Wire Proportional Counter (MWPC) with a Xe/CO{sub 2} gas thickness of 12mm provides sufficient absorption probability for TR-photons in combination with self-supporting low density PE foam or micro-structured foil radiators. A continuous investigation aiming at an optimal wire and pad-plane geometry, as well as a minimization of the material budget between active gas and radiator has been presented in hard- and software. A minimum photon absorption cross-section of the entrance window was realized with a thermally stretched aluminized Kapton foil, glued to a G11 support grid support frame. This structure limits the mechanical deformation of the entire window to 1mm/mbar. All MWPC prototypes include two wire planes. A symmetric amplification region of 2 x (3, 3.5 or 4)mm is followed by a short drift region of 6, 5 or 4 mm. The drift region reduces the gain

  6. Development, simulation and test of transition radiation detector prototypes for the compressed baryonic matter experiment at the facility for antiproton and ion research

    International Nuclear Information System (INIS)

    Bergmann, Cyrano S.H.

    2014-01-01

    The focus of this thesis is the development of a Transition Radiation Detector (TRD) for the Compressed Baryonic Matter (CBM) experiment at FAIR. The TRD sub-detector will contribute to the global particle identification and track reconstruction of charged particles. The technical design goal for the TRD is to identify 90% electrons with a maximum pion contamination of 1%. The TRD and Ring Image CHerenkov (RICH) detector should reach a common pion rejection of 10 4 , in order to measure charmonium and low-mass vector mesons. The position resolution should be between 200 and 300 μm in the anode wire direction. The most demanding aspect of the CBM TRD design is the high interaction rate of up to 10 7 Hz resulting in a charged particle rate of up to 100 kHz/cm 2 in the central part of the detector planes at SIS300 conditions. It is crucial to find the optimal radiator detector combination with a minimum material budget to limit scattering and background due to conversions and at the same time reach a sufficient pion rejection and position resolution. In this thesis it is confirmed that a Multi-Wire Proportional Counter (MWPC) with a Xe/CO 2 gas thickness of 12mm provides sufficient absorption probability for TR-photons in combination with self-supporting low density PE foam or micro-structured foil radiators. A continuous investigation aiming at an optimal wire and pad-plane geometry, as well as a minimization of the material budget between active gas and radiator has been presented in hard- and software. A minimum photon absorption cross-section of the entrance window was realized with a thermally stretched aluminized Kapton foil, glued to a G11 support grid support frame. This structure limits the mechanical deformation of the entire window to 1mm/mbar. All MWPC prototypes include two wire planes. A symmetric amplification region of 2 x (3, 3.5 or 4)mm is followed by a short drift region of 6, 5 or 4 mm. The drift region reduces the gain variation due to

  7. Radioactivity and associated radiation hazards in ceramic raw materials and end products.

    Science.gov (United States)

    Viruthagiri, G; Rajamannan, B; Suresh Jawahar, K

    2013-12-01

    Studies have been planned to obtain activity and associated radiation hazards in ceramic raw materials (quartz, feldspar, clay, zircon, kaolin, grog, alumina bauxite, baddeleyite, masse, dolomite and red mud) and end products (ceramic brick, glazed ceramic wall and floor tiles) as the activity concentrations of uranium, thorium and potassium vary from material to material. The primordial radionuclides in ceramic raw materials and end products are one of the sources of radiation hazard in dwellings made of these materials. By the determination of the activity level in these materials, the indoor radiological hazard to human health can be assessed. This is an important precautionary measure whenever the dose rate is found to be above the recommended limits. The aim of this work was to measure the activity concentration of (226)Ra, (232)Th and (40)K in ceramic raw materials and end products. The activity of these materials has been measured using a gamma-ray spectrometry, which contains an NaI(Tl) detector connected to multichannel analyser (MCA). Radium equivalent activity, alpha-gamma indices and radiation hazard indices associated with the natural radionuclides are calculated to assess the radiological aspects of the use of the ceramic end products as decorative or covering materials in construction sector. Results obtained were examined in the light of the relevant international legislation and guidance and compared with the results of similar studies reported in different countries. The results suggest that the use of ceramic end product samples examined in the construction of dwellings, workplace and industrial buildings is unlikely to give rise to any significant radiation exposure to the occupants.

  8. Radioactivity and associated radiation hazards in ceramic raw materials and end products

    International Nuclear Information System (INIS)

    Viruthagiri, G.; Rajamannan, B.; Suresh Jawahar, K.

    2013-01-01

    Studies have been planned to obtain activity and associated radiation hazards in ceramic raw materials (quartz, feldspar, clay, zircon, kaolin, grog, alumina bauxite, baddeleyite, masse, dolomite and red mud) and end products (ceramic brick, glazed ceramic wall and floor tiles) as the activity concentrations of uranium, thorium and potassium vary from material to material. The primordial radionuclides in ceramic raw materials and end products are one of the sources of radiation hazard in dwellings made of these materials. By the determination of the activity level in these materials, the indoor radiological hazard to human health can be assessed. This is an important precautionary measure whenever the dose rate is found to be above the recommended limits. The aim of this work was to measure the activity concentration of 226 Ra, 232 Th and 40 K in ceramic raw materials and end products. The activity of these materials has been measured using a gamma-ray spectrometry, which contains an NaI(Tl) detector connected to multichannel analyser (MCA). Radium equivalent activity, alpha-gamma indices and radiation hazard indices associated with the natural radionuclides are calculated to assess the radiological aspects of the use of the ceramic end products as decorative or covering materials in construction sector. Results obtained were examined in the light of the relevant international legislation and guidance and compared with the results of similar studies reported in different countries. The results suggest that the use of ceramic end product samples examined in the construction of dwellings, workplace and industrial buildings is unlikely to give rise to any significant radiation exposure to the occupants. (authors)

  9. Current problems in semiconductor detectors for high energy physics after particle irradiations

    International Nuclear Information System (INIS)

    Lazanu, Ionel

    2002-01-01

    The use of semiconductor materials as detectors in high radiation environments, as expected in future high energy accelerators or in space missions, poses severe problems in long-time operations, due to changes in the properties of the material, and consequently in the performances of detectors. This talk presents the major theoretical areas of current problems, reviews the works in this field and the stage of their understanding, including author's contributions The mechanisms of interaction of the projectile with the semiconductor, the production of primary defects, the physical quantities and the equations able to characterise and describe the radiation effects, and the equations of kinetics of defects are considered. Correlation between microscopic damage and detector performances and the possible ways to optimise the radiation hardness of materials are discussed. (author)

  10. Detection of electron and hole traps in CdZnTe radiation detectors by thermoelectric emission spectroscopy and thermally stimulated conductivity

    International Nuclear Information System (INIS)

    Lee, E.Y.; Brunett, B.A.; Olsen, R.W.; Van Scyoc, J.M. III; Hermon, H.; James, R.B.

    1998-01-01

    The electrical properties of CdZnTe radiation detectors are largely determined by electron and hole traps in this material. The traps, in addition to degrading the detector performance, can function as dopants and determine the resistivity of the material. Thermoelectric emission spectroscopy and thermally stimulated conductivity are used to detect these traps in a commercially available spectrometer-grade CdZnTe detector, and the electrical resistivity is measured as a function of temperature. A deep electron trap having an energy of 695 meV and cross section of 8 x 10 -16 cm 2 is detected and three hole traps having energies of 70 ± 20 meV, 105 ± 30 meV and 694 ± 162 meV are detected. A simple model based on these traps explains quantitatively all the data, including the electrical properties at room temperature and also their temperature dependence

  11. Medical imaging: Material change for X-ray detectors

    Science.gov (United States)

    Rowlands, John A.

    2017-10-01

    The X-ray sensitivity of radiology instruments is limited by the materials used in their detectors. A material from the perovskite family of semiconductors could allow lower doses of X-rays to be used for medical imaging. See Letter p.87

  12. High sensitive radiation detector for radiology dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Valente, M.; Malano, F. [Instituto de Fisica Enrique Gaviola, Oficina 102 FaMAF - UNC, Av. Luis Medina Allende, Ciudad Universitaria, 5000 Cordoba (Argentina); Molina, W.; Vedelago, J., E-mail: valente@famac.unc.edu.ar [Laboratorio de Investigaciones e Instrumentacion en Fisica Aplicada a la Medicina e Imagenes por Rayos X, Laboratorio 448 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2014-08-15

    Fricke solution has a wide range of applications as radiation detector and dosimetry. It is particularly appreciated in terms of relevant comparative advantages, like tissue equivalence when prepared in aqueous media like gel matrix, continuous mapping capability, dose rate recorded and incident direction independence as well as linear dose response. This work presents the development and characterization of a novel Fricke gel system, based on modified chemical compositions making possible its application in clinical radiology. Properties of standard Fricke gel dosimeter for high dose levels are used as starting point and suitable chemical modifications are introduced and carefully investigated in order to attain high resolution for low dose ranges, like those corresponding to radiology interventions. The developed Fricke gel radiation dosimeter system achieves the expected typical dose dependency, actually showing linear response in the dose range from 20 up to 4000 mGy. Systematic investigations including several chemical compositions are carried out in order to obtain a good enough dosimeter response for low dose levels. A suitable composition among those studied is selected as a good candidate for low dose level radiation dosimetry consisting on a modified Fricke solution fixed to a gel matrix containing benzoic acid along with sulfuric acid, ferrous sulfate, xylenol orange and ultra-pure reactive grade water. Dosimeter samples are prepared in standard vials for its in phantom irradiation and further characterization by spectrophotometry measuring visible light transmission and absorbance before and after irradiation. Samples are irradiated by typical kV X-ray tubes and calibrated Farmer type ionization chamber is used as reference to measure dose rates inside phantoms in at vials locations. Once sensitive material composition is already optimized, dose-response curves show significant improvement regarding overall sensitivity for low dose levels. According to

  13. High sensitive radiation detector for radiology dosimetry

    International Nuclear Information System (INIS)

    Valente, M.; Malano, F.; Molina, W.; Vedelago, J.

    2014-08-01

    Fricke solution has a wide range of applications as radiation detector and dosimetry. It is particularly appreciated in terms of relevant comparative advantages, like tissue equivalence when prepared in aqueous media like gel matrix, continuous mapping capability, dose rate recorded and incident direction independence as well as linear dose response. This work presents the development and characterization of a novel Fricke gel system, based on modified chemical compositions making possible its application in clinical radiology. Properties of standard Fricke gel dosimeter for high dose levels are used as starting point and suitable chemical modifications are introduced and carefully investigated in order to attain high resolution for low dose ranges, like those corresponding to radiology interventions. The developed Fricke gel radiation dosimeter system achieves the expected typical dose dependency, actually showing linear response in the dose range from 20 up to 4000 mGy. Systematic investigations including several chemical compositions are carried out in order to obtain a good enough dosimeter response for low dose levels. A suitable composition among those studied is selected as a good candidate for low dose level radiation dosimetry consisting on a modified Fricke solution fixed to a gel matrix containing benzoic acid along with sulfuric acid, ferrous sulfate, xylenol orange and ultra-pure reactive grade water. Dosimeter samples are prepared in standard vials for its in phantom irradiation and further characterization by spectrophotometry measuring visible light transmission and absorbance before and after irradiation. Samples are irradiated by typical kV X-ray tubes and calibrated Farmer type ionization chamber is used as reference to measure dose rates inside phantoms in at vials locations. Once sensitive material composition is already optimized, dose-response curves show significant improvement regarding overall sensitivity for low dose levels. According to

  14. Alpha-ray spectrometry at high temperature by using a compound semiconductor detector.

    Science.gov (United States)

    Ha, Jang Ho; Kim, Han Soo

    2013-11-01

    The use of conventional radiation detectors in harsh environments is limited by radiation damage to detector materials and by temperature constraints. We fabricated a wide-band gap semiconductor radiation detector based on silicon carbide. All the detector components were considered for an application in a high temperature environment like a nuclear reactor core. The radiation response, especially to alpha particles, was measured using an (241)Am source at variable operating voltages at room temperature in the air. The temperature on detector was controlled from 30°C to 250°C. The alpha-particle spectra were measured at zero bias operation. Even though the detector is operated at high temperature, the energy resolution as a function of temperature is almost constant within 3.5% deviation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. SiC detectors to monitor ionizing radiations emitted from nuclear events and plasmas

    Science.gov (United States)

    Torrisi, L.; Cannavò, A.

    2016-09-01

    Silicon Carbide (SiC) semiconductor detectors are increasingly employed in Nuclear Physics for their advantages with respect to traditional silicon (Si). Such detectors show an energy resolution, charge mobility, response velocity and detection efficiency similar to Si detectors. However, the higher band gap (3.26 eV), the lower leakage current (∼10 pA) maintained also at room temperature, the higher radiation hardness and the higher density with respect to Si represent some indisputable advantages characterizing such detectors. The devices can be employed at high temperatures, at high absorbed doses and in the case of high visible light intensities, for example, in plasma, for limited exposition times without damage. Generally SiC Schottky diodes are employed in reverse polarization with an active region depth of the order of 100 µm, purity below 1014 cm-3 and an active area lower than 1 cm2. Measurements in the regime of proportionality with the radiation energy released in the active region and measurements in time-of-flight configuration are employed for nuclear emission events produced at both low and high fluences. Alpha spectra demonstrated an energy resolution of about 1.3% at 5.8 MeV. Radiation emission from laser-generated plasma can be monitored in terms of detected photons, electrons and ions, using the laser pulse as a start signal and the radiation detection as a stop signal, enabling to measure the ion velocity by knowing the target-detector flight distance. SiC spectra acquired in the Messina University laboratories using radioactive ion sources and at the PALS laboratory facility in Prague (Czech Republic) are presented. A preliminary study of the use of SiC detectors, embedded in a water equivalent polymer, as a dosimeter is presented and discussed.

  16. Method for manufacturing nuclear radiation detector with deep diffused junction

    International Nuclear Information System (INIS)

    Hall, R.N.

    1977-01-01

    Germanium radiation detectors are manufactured by diffusing lithium into high purity p-type germanium. The diffusion is most readily accomplished from a lithium-lead-bismuth alloy at approximately 430 0 C and is monitored by a quartz half cell containing a standard composition of this alloy. Detectors having n-type cores may be constructed by converting high purity p-type germanium to n-type by a lithium diffusion and subsequently diffusing some of the lithium back out through the surface to create a deep p-n junction. Production of coaxial germanium detectors comprising deep p-n junctions by the lithium diffusion process is described

  17. 3D Detectors for Synchrotron Applications

    CERN Document Server

    Pennicard, D

    2009-01-01

    3D detectors are a novel variety of photodiode radiation detector, invented by Parker, Kenney and Segal (1997). Instead of having n- and p-type contacts on the front and back surfaces of a silicon substrate, like a standard photodiode, they have columns of doped material passing through the thickness of the silicon. This structure means that the detector can combine a reasonable substrate thickness with a very small electrode spacing, resulting in a low depletion voltage, fast charge collection and low charge sharing. These detectors have a couple of promising applications. Their fast charge collection and low depletion voltage should make them very radiation-tolerant. So, they could be used for future particle physics experiments at the Super Large Hadron Collider (SLHC), where high levels of radiation damage are expected. Also, their low charge sharing means they could potentially improve X-ray diffraction measurements at synchrotrons such as Diamond Light Source. This would allow these experiments, for exa...

  18. Radiation resistance of γ-detector modules at the labelling station of labelled neutrino complex

    International Nuclear Information System (INIS)

    Pishchal'nikov, Yu.M.

    1986-01-01

    The data on efficiency and transparency decrease of various types of lightpipe-spectrum (LSS) and scintillation plates on the basis of PMMA and polystyrene under the dose irradiation ranging from 10 4 to 3x10 6 rad have been obtained. Sample irradiation was carried out in a wide muon beam and with the intensive radioactie source 60 Co. The deterioration in the γ-detector (TNF) energy resolution due to the radiation damage of scintillators and (LSS) is discussed. Radiation damage of the lead glass detectors (the GAMS detector) and ''sandwich'' type modules have been compared

  19. 75 FR 27205 - Hazardous Materials: Incorporation of Special Permits Into Regulations

    Science.gov (United States)

    2010-05-14

    ... specially designed radiation detectors containing a Division 2.2 (non-flammable gas) material under a new.... Radiation Detectors Radiation detectors are used for measuring the intensity of ionizing radiation. The... visual inspection of the rupture disc in a non-reclosing pressure relief device of a rail tank car...

  20. Test beam performance of a tracking TRD [Transition Radiation Detector] prototype

    International Nuclear Information System (INIS)

    Shank, J.T.; Whitaker, J.S.; Polychronakos, V.A.; Radeka, V.; Stephani, D.; Beker, H.; Bock, R.K.; Botlo, M.; Fabjan, C.W.; Pfennig, J.; Price, M.J.; Willis, W.J.; Akesson, T.; Chernyatin, V.; Dolgoshein, B.; Nevsky, P.; Potekhin, M.; Romanjuk, A.; Sosnovtsev, V.; Gavrilenko, I.; Muravjev, S.; Shmeleva, A.

    1990-01-01

    A Tracking Transition Radiation Detector prototype has been constructed and tested. It consists of 240 straw tubes, 4 mm in diameter, imbedded in a polyethylene block acting as the radiator. Its performance as an electron identifier as well as a tracking device for minimum ionizing particles has been determined. 2 refs., 6 figs

  1. Low-Power Large-Area Radiation Detector for Space Science Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this task is to develop a low-power, large-area detectors from SiC, taking advantage of very low thermal noise characteristics and high radiation...

  2. Simulation and test of 3D silicon radiation detectors

    International Nuclear Information System (INIS)

    Fleta, C.; Pennicard, D.; Bates, R.; Parkes, C.; Pellegrini, G.; Lozano, M.; Wright, V.; Boscardin, M.; Dalla Betta, G.-F.; Piemonte, C.; Pozza, A.; Ronchin, S.; Zorzi, N.

    2007-01-01

    The work presented here is the result of the collaborative effort between the University of Glasgow, ITC-IRST (Trento) and IMB-CNM (Barcelona) in the framework of the CERN-RD50 Collaboration to produce 3D silicon radiation detectors and study their performance. This paper reports on two sets of 3D devices. IRST and CNM have fabricated a set of single-type column 3D detectors, which have columnar electrodes of the same doping type and an ohmic contact located at the backplane. Simulations of the device behaviour and electrical test results are presented. In particular, current-voltage, capacitance-voltage and charge collection efficiency measurements are reported. Other types of structures called double-sided 3D detectors are currently being fabricated at CNM. In these detectors the sets of n and p columns are made on opposite sides of the device. Electrical and technological simulations and first processing results are presented

  3. Recent advances in Tl Br, Cd Te and CdZnTe semiconductor radiation detectors: a review

    International Nuclear Information System (INIS)

    Oliveira, Icimone B.

    2011-01-01

    The success in the development of radiation spectrometers operating at room temperature is based on many years of effort on the part of large numbers of workers around the world. These individuals have contributed to the understanding of the fundamental materials issues associated with the growth of semiconductors for this application, the development of device fabrication and processing technology, and advances in low noise electronics and pulse processing. Progress in this field continues at an accelerated pace, as in evidenced by the improvements in detector performance and by the growing number of commercial products. Thus, the last years have been seen continued effort in the development of room temperature compound semiconductors devices. High-Z compound semiconductor detectors has been explored for high energy resolution, high detection efficiency and are of low cost. Compound semiconductors detectors are well suited for addressing needs of demanding applications such as bore hole logging where high operating temperature are encountered. In this work recent developments in semiconductors detectors were reviewed. This review concentrated on thallium bromide (TlBr), cadmium zinc telluride (CdZnTe) and cadmium telluride (CdTe) crystals detectors. TlBr has higher stopping power compared to common semiconductor materials because it has the higher photoelectric and total attenuation coefficients over wide energy range from 100 keV to 1 MeV. CdTe and CdZnTe detectors have several attractive features for detecting X-ray and low energy gamma ray. Their relatively large band gaps lead to a relatively low leakage current and offer an excellent energy resolution at room temperature. A literature survey and bibliography was also included. (author)

  4. Recent advances in Tl Br, Cd Te and CdZnTe semiconductor radiation detectors: a review

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Icimone B. [Universidade Bandeirante (UNIBAN), Sao Paulo, SP (Brazil)

    2011-07-01

    The success in the development of radiation spectrometers operating at room temperature is based on many years of effort on the part of large numbers of workers around the world. These individuals have contributed to the understanding of the fundamental materials issues associated with the growth of semiconductors for this application, the development of device fabrication and processing technology, and advances in low noise electronics and pulse processing. Progress in this field continues at an accelerated pace, as in evidenced by the improvements in detector performance and by the growing number of commercial products. Thus, the last years have been seen continued effort in the development of room temperature compound semiconductors devices. High-Z compound semiconductor detectors has been explored for high energy resolution, high detection efficiency and are of low cost. Compound semiconductors detectors are well suited for addressing needs of demanding applications such as bore hole logging where high operating temperature are encountered. In this work recent developments in semiconductors detectors were reviewed. This review concentrated on thallium bromide (TlBr), cadmium zinc telluride (CdZnTe) and cadmium telluride (CdTe) crystals detectors. TlBr has higher stopping power compared to common semiconductor materials because it has the higher photoelectric and total attenuation coefficients over wide energy range from 100 keV to 1 MeV. CdTe and CdZnTe detectors have several attractive features for detecting X-ray and low energy gamma ray. Their relatively large band gaps lead to a relatively low leakage current and offer an excellent energy resolution at room temperature. A literature survey and bibliography was also included. (author)

  5. Pin Diode Detector For Radiation Field Monitoring In A Current Mode

    International Nuclear Information System (INIS)

    Beck, A.; Wengrowicz, U.; Kadmon, Y.; Tirosh, D.; Osovizky, A.; Vulasky, E.; Tal, N.

    1999-01-01

    Thus paper presents calculations and tests made for a detector based on a bare Pin diode and a Pin diode coupled to a plastic scintillator. These configurations have a variety of applications in radiation field monitoring. For example, the Positron Emission Tomography (PET) technology which becomes an established diagnostic imaging modality. Flour-18 is one of the major isotopes being used by PET imaging. The PET method utilizes short half life β + radioisotopes which, by annihilation, produce a pair of high energy photons (511 keV). Fluoro-deoxyglucose producers are required to meet federal regulations and licensing requirements. Some of the regulations are related to the production in chemistry modules regarding measuring the Start Of Synthesis (SOS) activity and verifying the process repeatability. Locating a radiation detector based on Pin diode inside the chemistry modules is suitable for this purpose. The dimensions of a Pin diode based detector can be small, with expected linearity over several scale decades

  6. Notes on radiation effects on materials

    International Nuclear Information System (INIS)

    Anno, J.N.

    1984-01-01

    The effects of radiation from nuclear reactions on various classes of materials are examined in an introductory textbook for students of nuclear engineering. Topics discussed include the units and general scale of radiation damage, fundamental interactions of neutrons and gamma rays with materials, transient radiation effects on electrical components, radiation effects on organic materials and on steels, nuclear fission effects, surface effects of nuclear radiations, radiation effects on biological material, and neutron and gamma-ray dosimetry. Graphs, diagrams, tables of numerical data, and problems for each chapter are provided. 122 references

  7. CZT Virtual Frisch-grid Detector: Principles and Applications

    International Nuclear Information System (INIS)

    Cui, Y.; Bolotnikov, A.; Camarda, G.; Hossain, A.; James, R.B.

    2009-01-01

    Cadmium Zinc Telluride (CdZnTe or CZT) is a very attractive material for using as room-temperature semiconductor detectors, because it has a wide bandgap and a high atomic number. However, due to the material's poor hole mobility, several special techniques were developed to ensure its suitability for radiation detection. Among them, the virtual Frisch-grid CZT detector is an attractive option, having a simple configuration, yet delivering an outstanding spectral performance. The goal of our group in Brookhaven National Laboratory (BNL) is to improve the performance of Frisch-ring CZT detectors; most recently, that effort focused on the non-contacting Frisch-ring detector, allowing us to build an inexpensive, large-volume detector array with high energy-resolution and a large effective area. In this paper, the principles of virtual Frisch-grid detectors are described, especially BNL's innovative improvements. The potential applications of virtual Frisch-grid detectors are discussed, and as an example, a hand-held gamma-ray spectrometer using a CZT virtual Frischgrid detector array is introduced, which is a self-contained device with a radiation detector, readout circuit, communication circuit, and high-voltage supply. It has good energy resolution of 1.4% (FWHM of 662-keV peak) with a total detection volume of ∼20 cm 3 . Such a portable inexpensive device can be used widely in nonproliferation applications, non-destructive detection, radiation imaging, and for homeland security. Extended systems based on the same technology have potential applications in industrial- and nuclear-medical-imaging

  8. Radiation damage studies of detector-compatible Si JFETs

    International Nuclear Information System (INIS)

    Dalla Betta, Gian-Franco; Boscardin, Maurizio; Candelori, Andrea; Pancheri, Lucio; Piemonte, Claudio; Ratti, Lodovico; Zorzi, Nicola

    2007-01-01

    We have largely improved the performance of our detector-compatible Si JFETs by optimizing the fabrication technology. New devices feature thermal noise values close to the theoretical ones, and remarkably low 1/f noise figures. In view of adopting these JFETs for X-ray imaging and HEP applications, bulk and surface radiation damage tests have been carried out by irradiating single transistors and test structures with neutrons and X-rays. Selected results from static and noise characterization of irradiated devices are discussed in this paper, and the impact of radiation effects on the performance of JFET-based circuits is addressed

  9. A precision synchrotron radiation detector using phosphorescent screens

    International Nuclear Information System (INIS)

    Jung, C.K.; Lateur, M.; Nash, J.; Tinsman, J.; Butler, J.; Wormser, G.

    1990-01-01

    A precision detector to measure synchrotron radiation beam positions has been designed and installed as part of beam energy spectrometers at the Stanford Linear Collider (SLC). The distance between pairs of synchrotron radiation beams is measured absolutely to better than 28 μm on a pulse-to-pulse basis. This contributes less than 5 MeV to the error in the measurement of SLC beam energies (approximately 50 GeV). A system of high-resolution video cameras viewing precisely aligned fiducial wire arrays overlaying phosphorescent screens has achieved this accuracy. 3 refs., 5 figs., 1 tab

  10. Radiation hard silicon microstrip detectors for Tevatron experiments

    International Nuclear Information System (INIS)

    Korjenevski, Sergey

    2004-01-01

    The Silicon Microstrip Tracking detectors at the CDF and D0 experiments have now been operating for almost three years at Fermilab. These detectors were designed originally for an integrated luminosity of 2fb -1 . As the expected luminosity for Run IIb at the Tevatron collider was initially envisioned to reach 15fb -1 , radiation tolerances of both devices were revisited, culminating in proposals for new systems. With reduced expectations for total luminosity at ∼6fb -1 , the full detector-replacement projects were terminated. The CDF detector is expected nevertheless to cope efficiently with the lower anticipated dose, however, the D0 experiment is planning a smaller-scale project: a Layer-0 (L0) upgrade of the silicon tracker (D0SMT). The new device will fit between the beam line and the inner layer of the current Tracker. Built of single-sided sensors, this upgrade is expected to perform well in the harsh radiation environment, and be able to withstand an integrated luminosity of 15fb -1 . Prototypes of Run IIb sensors were irradiated using 10MeV protons at the tandem Van de Graaff at the James R. McDonald Laboratory at Kansas State University. A fit to the 10MeV proton data yields a damage parameter αp=11x10-17Acm. This is consistent with results from RD48 (αp=9.9x10-17Acm). The scaling of damage to 1MeV neutron fluence uses a hardness factor (κ) derived from the non-ionizing components of the energy loss (NEIL). NEIL predicts a hardness factor of 3.87 for 10MeV protons. We obtained an experimental value of this factor of 2.54, or 34% smaller than scaling predictions from NEIL

  11. The ALICE Transition Radiation Detector: Construction, operation, and performance

    Czech Academy of Sciences Publication Activity Database

    Acharya, S.; Adamová, Dagmar; Bielčík, J.; Bielčíková, Jana; Brož, M.; Contreras, J. G.; Ferencei, Jozef; Hladký, Jan; Horák, D.; Křížek, Filip; Kučera, Vít; Kushpil, Svetlana; Lavička, R.; Mareš, Jiří A.; Petráček, V.; Šumbera, Michal; Vaňát, Tomáš; Závada, Petr

    2018-01-01

    Roč. 881, č. 2 (2018), s. 88-127 ISSN 0168-9002 R&D Projects: GA MŠk(CZ) LG15052 Institutional support: RVO:68378271 ; RVO:61389005 Keywords : fibre/foam sendwich radiator * transition radiation detector * multi-wire proportional drift chamber * Xenon-based gas micture * tracking * lonisation energy loss Subject RIV: BG - Nuclear, Atomic and Molecular Physics , Colliders; BF - Elementary Particles and High Energy Physics (FZU-D) OBOR OECD: Nuclear physics ; Particles and field physics (FZU-D) Impact factor: 1.362, year: 2016

  12. Array element of a space-based synchrotron radiation detector

    International Nuclear Information System (INIS)

    Lee, M.W.; Commichau, S.C.; Kim, G.N.; Son, D.; Viertel, G.M.

    2006-01-01

    A synchrotron radiation detector (SRD) has been proposed as part of the Alpha Magnetic Spectrometer experiment on the International Space Station to study cosmic ray electrons and positrons in the TeV energy range. The SRD will identify these particles by detecting their emission of synchrotron radiation in the Earth's magnetic field. This article reports on the study of key technical parameters for the array elements which form the SRD, including the choice of the detecting medium, the sensor and the readout system

  13. Mars science laboratory radiation assessment detector (MSL/RAD) modeling workshop proceedings

    Science.gov (United States)

    Hassler, Donald M.; Norbury, John W.; Reitz, Günther

    2017-08-01

    The Radiation Assessment Detector (RAD) (Hassler et al., 2012; Zeitlin et al., 2016) onboard the Mars Science Laboratory (MSL) Curiosity rover (Grotzinger et al., 2012) is a sophisticated charged and neutral particle radiation analyzer developed by an international team of scientists and engineers from Southwest Research Institute in Boulder, Colorado as the leading institution, the University of Kiel and the German Aerospace Center in Cologne, Germany. RAD is a compact, powerful instrument capable of distinguishing between ionizing particles and neutral particles and providing neutron, gamma, and charged particle spectra from protons to iron as well as absorbed dose measurements in tissue-equivalent material. During the 6 month cruise to Mars, inside the MSL spacecraft, RAD served as a proxy to validate models of the radiation levels expected inside a spacecraft that future astronauts might experience (Zeitlin et al., 2013). RAD was turned on one day after the landing on August 7, 2012, exactly 100 years to the day after the discovery of cosmic rays on Earth by Victor Hess. These measurements are the first of their kind on the surface of another planet (Hassler et al., 2014), and the radiation data collected by RAD on the surface of Mars will inform projections of crew health risks and the design of protective surface habitats and other countermeasures for future human missions in the coming decades.

  14. Radiation hardness of silicon detectors - a challenge from high-energy physics

    CERN Document Server

    Lindström, G; Fretwurst, E

    1999-01-01

    An overview of the radiation-damage-induced problems connected with the application of silicon particle detectors in future high-energy physics experiments is given. Problems arising from the expected hadron fluences are summarized and the use of the nonionizing energy loss for normalization of bulk damage is explained. The present knowledge on the deterioration effects caused by irradiation is described leading to an appropriate modeling. Examples are given for a correlation between the change in the macroscopic performance parameters and effects to be seen on the microscopic level by defect analysis. Finally possible ways are out-lined for improving the radiation tolerance of silicon detectors either by operational conditions, process technology or defect engineering.

  15. Observation of microwave radiation using low-cost detectors at the ANKA storage ring*

    CERN Document Server

    Judin, V; Hofmann, A; Huttel, E; Kehrer, B; Klein, M; Marsching, S; Müller, A S; Nasse, M; Smale, N; Caspers, F; Peier, P

    2011-01-01

    Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed, because the vacuum chamber cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: the accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches [1]. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths below the waveguide shielding cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually use...

  16. Radiation pager

    International Nuclear Information System (INIS)

    Warren, J.L.; Vadnais, K.G.

    1998-01-01

    Methods of interdicting nuclear materials to date have favored the use of large portal detectors at choke points, or hand carried instruments used by trained personnel for conducting spot searches. Although these methods are effective in some instances, it is often impractical to insert choke points at busy traffic areas, and it is not cost effective to maintain a force of skilled operators whose focus is nuclear interdiction. Recent technology developments are causing profound changes in the philosophy and methods employed for interdicting nuclear materials. Breakthrough advances in the miniaturization of detectors and low power electronics have made possible a new class of small gamma-ray radiation detectors, roughly the size of a message pager, with unprecedented sensitivity for their size. These instruments, named Radiation Pagers TM , are ideally suited for use by untrained individual law enforcement personnel and emergency responders in the course of their regular duties. New tactics that utilize a radiation detector worn by every officer are creating a moving curtain of detection with a significantly higher likelihood of locating illicit nuclear contraband. These individual detectors also provide each officer with a high level of confidence that they are not being unknowingly irradiated in the course of their work. (author)

  17. Charge transport properties of CdMnTe radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kim K.; Rafiel, R.; Boardman, M.; Reinhard, I.; Sarbutt, A.; Watt, G.; Watt, C.; Uxa, S.; Prokopovich, D.A.; Belas, E.; Bolotnikov, A.E.; James, R.B.

    2012-04-11

    Growth, fabrication and characterization of indium-doped cadmium manganese telluride (CdMnTe)radiation detectors have been described. Alpha-particle spectroscopy measurements and time resolved current transient measurements have yielded an average charge collection efficiency approaching 100 %. Spatially resolved charge collection efficiency maps have been produced for a range of detector bias voltages. Inhomogeneities in the charge transport of the CdMnTe crystals have been associated with chains of tellurium inclusions within the detector bulk. Further, it has been shown that the role of tellurium inclusions in degrading chargecollection is reduced with increasing values of bias voltage. The electron transit time was determined from time of flight measurements. From the dependence of drift velocity on applied electric field the electron mobility was found to be n = (718 55) cm2/Vs at room temperature.

  18. Epitaxy - a new technology for fabrication of advanced silicon radiation detectors

    International Nuclear Information System (INIS)

    Kemmer, J.; Wiest, F.; Pahlke, A.; Boslau, O.; Goldstrass, P.; Eggert, T.; Schindler, M.; Eisele, I.

    2005-01-01

    Twenty five years after the introduction of the planar process to the fabrication of silicon radiation detectors a new technology, which replaces the ion implantation doping by silicon epitaxy is presented. The power of this new technique is demonstrated by fabrication of silicon drift detectors (SDDs), whereby both the n-type and p-type implants are replaced by n-type and p-type epi-layers. The very first SDDs ever produced with this technique show energy resolutions of 150 eV for 55 Fe at -35 deg C. The area of the detectors is 10 mm 2 and the thickness 300 μm. The high potential of epitaxy for future detectors with integrated complex electronics is described

  19. Radiation effects in semiconductors

    CERN Document Server

    2011-01-01

    There is a need to understand and combat potential radiation damage problems in semiconductor devices and circuits. Written by international experts, this book explains the effects of radiation on semiconductor devices, radiation detectors, and electronic devices and components. These contributors explore emerging applications, detector technologies, circuit design techniques, new materials, and innovative system approaches. The text focuses on how the technology is being used rather than the mathematical foundations behind it. It covers CMOS radiation-tolerant circuit implementations, CMOS pr

  20. PantherPix hybrid pixel γ-ray detector for radio-therapeutic applications

    Science.gov (United States)

    Neue, G.; Benka, T.; Havránek, M.; Hejtmánek, M.; Janoška, Z.; Kafka, V.; Korchak, O.; Lednický, D.; Marčišovská, M.; Marčišovský, M.; Popule, J.; Şmarhák, J.; Şvihra, P.; Tomášek, L.; Vrba, V.; Konček, O.; Semmler, M.

    2018-02-01

    This work focuses on the design of a semiconductor pixelated γ-ray camera with a pixel size of 1 mm2. The cost of semiconductor manufacturing is mainly driven by economies of scale, which makes silicon the cheapest semiconductor material due to its widespread utilization. The energy of γ-photons used in radiation therapy are in a range, in which the dominant interaction mechanism is Compton scattering in every conceivable sensor material. Since the Compton scattering cross section is linearly dependent upon Z, it is less rewarding to utilize high Z sensor materials, than it is in the case of X-ray detectors (X-rays interact also via the photoelectric effect whose cross section scales proportional to Zn, where n is ≈ 4,5). For the stated reasons it was decided to use the low Z material silicon (Z = 14) despite its worse detection efficiency. The proposed detector is designed as a portal detector to be used in radiation cancer therapy. The purpose of the detector is to ensure correct patient alignment, spatial dose monitoring and to provide the feedback necessary for an emergency shutdown should the spatial dose rate profile deviate from the treatment plan. Radiation therapy equipment is complex and thus failure prone and the consequences of malfunction are often life threatening. High spatial resolution and high detection efficiency are not a high design priority. The detector design priorities are focused up on radiation hardness, robustness and the ability to cover a large area cost efficiently. The quintessential idea of the PanterPix detector exploits the relaxed spatial resolution requirement to achieve the stated goals. The detector is composed of submodules, each submodule consisting of a Si sensor with an array of fully depleted detection diodes and 8 miniature custom design readout ASICs collecting and measuring the minuscule charge packets generated due to ionization in the PN junctions.