Tracking with heavily irradiated silicon detectors operated at cryogenic temperatures

International Nuclear Information System (INIS)

Casagrande, L.; Barnett, B.M.; Bartalina, P.

1999-01-01

In this work, the authors show that a heavily irradiated double-sided silicon microstrip detector recovers its performance when operated at cryogenic temperatures. A DELPHI microstrip detector, irradiated to a fluence of ∼4 x 10 14 p/cm 2 , no longer operational at room temperature, cannot be distinguished from a non-irradiated one when operated at T < 120 K. Besides confirming the previously observed Lazarus effect in single diodes, these results establish, for the first time, the possibility of using standard silicon detectors for tracking applications in extremely demanding radiation environments

Pulse laser irradiation into superconducting MgB2 detector

International Nuclear Information System (INIS)

Fujiwara, Daisuke; Miki, Shigehito; Satoh, Kazuo; Yotsuya, Tsutomu; Shimakage, Hisashi; Wang, Zhen; Okayasu, Satoru; Katagiri, Masaki; Machida, Masahiko; Kato, Masaru; Ishida, Takekazu

2005-01-01

We performed 20-ps pulse laser irradiation experiments on a MgB 2 neutron detector to know a thermal-relaxation process for designing a MgB 2 neutron detector. The membrane-type structured MgB 2 device was fabricated to minimize the heat capacity of sensing part of a detector as well as to enhance its sensitivity. We successfully observed a thermal-relaxation signal resulting from pulse laser irradiation by developing a detection circuit. The response time was faster than 1 μs, meaning that the detector would be capable of counting neutrons at a rate of more than 10 6 events per second

Operation of heavily irradiated silicon detectors in non-depletion mode

International Nuclear Information System (INIS)

Verbitskaya, E.; Eremin, V.; Ilyashenko, I.; Li, Z.; Haerkoenen, J.; Tuovinen, E.; Luukka, P.

2006-01-01

The non-depletion detector operation mode has generally been disregarded as an option in high-energy physics experiments. In this paper, the non-depletion operation is examined by detailed analysis of the electric field distribution and the current pulse response of heavily irradiated silicon (Si) detectors. The previously reported model of double junction in heavily irradiated Si detector is further developed and a simulation of the current pulse response has been performed. It is shown that detectors can operate in a non-depletion mode due to the fact that the value of the electric field in a non-depleted region is high enough for efficient carrier drift. This electric field originates from the current flow through the detector and a consequent drop of the potential across high-resistivity bulk of a non-depleted region. It is anticipated that the electric field in a non-depleted region, which is still electrically neutral, increases with fluence that improves the non-depleted detector operation. Consideration of the electric field in a non-depleted region allows the explanation of the recorded double-peak current pulse shape of heavily irradiated Si detectors and definition of the requirements for the detector operational conditions. Detailed reconstruction of the electric field distribution gives new information on radiation effects in Si detectors

Charge transport in non-irradiated and irradiated silicon detectors

International Nuclear Information System (INIS)

Leroy, C.; Roy, P.; Casse, G.L.; Glaser, M.; Grigoriev, E.; Lemeilleur, F.

1999-01-01

A model describing the transport of the charge carriers generated in n-type silicon detectors by ionizing particles is presented. In order to reproduce the experimental current pulse responses induced by α and β particles in non-irradiated and irradiated detectors up to fluences (PHI) much beyond the n to p-type inversion, an n-type region 15 μm deep is introduced on the p + side of the diode. This model also gives mobilities which decrease linearly up to fluences of around 5x10 13 particles/cm 2 and beyond, converging to saturation values of about 1000 and 450 cm 2 /V s for electrons and holes, respectively. The charge carrier lifetime degradation with increased fluence, due to trapping, is responsible for a predicted charge collection deficit for β particles and for α particles which is found to agree with direct CCE measurements. (author)

Evaluation of Irradiated Barrel Detector Modules for the Upgrade of the CMS Pixel Detector

CERN Document Server

Sibille, Jennifer Ann

2013-01-01

Prototype detector modules comprising sensors and the new readout chips were assembled and irradiated with protons at the CERN PS, and readout chips without sensors have been irradiated with protons at the Karls...

ASTRO-H CdTe detectors proton irradiation at PIF

International Nuclear Information System (INIS)

Limousin, O.; Renaud, D.; Horeau, B.; Dubos, S.; Laurent, P.; Lebrun, F.; Chipaux, R.; Boatella Polo, C.; Marcinkowski, R.; Kawaharada, M.; Watanabe, S.; Ohta, M.; Sato, G.; Takahashi, T.

2015-01-01

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

Spectral Irradiance Measurements Based on Detector

International Nuclear Information System (INIS)

Lima, M S; Menegotto, T; Duarte, I; Da Silva, T Ferreira; Alves, L C; Alvarenga, A D; Almeida, G B; Couceiro, I B; Teixeira, R N

2015-01-01

This paper presents the preliminary results of the realization of absolute spectral irradiance scale at INMETRO in the ultraviolet, visible and infrared regions using filter radiometers as secondary standards. In the construction of these instruments are used, at least, apertures, interference filters and a trap detector. In the assembly of the trap detectors it was necessary to characterize several photocells in spatial uniformity and shunt resistance. All components were calibrated and these results were analyzed to mount the filter radiometer

Neutron irradiation test of depleted CMOS pixel detector prototypes

International Nuclear Information System (INIS)

Mandić, I.; Cindro, V.; Gorišek, A.; Hiti, B.; Kramberger, G.; Mikuž, M.; Zavrtanik, M.; Hemperek, T.; Daas, M.; Hügging, F.; Krüger, H.; Pohl, D.-L.; Wermes, N.; Gonella, L.

2017-01-01

Charge collection properties of depleted CMOS pixel detector prototypes produced on p-type substrate of 2 kΩ cm initial resistivity (by LFoundry 150 nm process) were studied using Edge-TCT method before and after neutron irradiation. The test structures were produced for investigation of CMOS technology in tracking detectors for experiments at HL-LHC upgrade. Measurements were made with passive detector structures in which current pulses induced on charge collecting electrodes could be directly observed. Thickness of depleted layer was estimated and studied as function of neutron irradiation fluence. An increase of depletion thickness was observed after first two irradiation steps to 1 · 10 13 n/cm 2 and 5 · 10 13 n/cm 2 and attributed to initial acceptor removal. At higher fluences the depletion thickness at given voltage decreases with increasing fluence because of radiation induced defects contributing to the effective space charge concentration. The behaviour is consistent with that of high resistivity silicon used for standard particle detectors. The measured thickness of the depleted layer after irradiation with 1 · 10 15 n/cm 2 is more than 50 μm at 100 V bias. This is sufficient to guarantee satisfactory signal/noise performance on outer layers of pixel trackers in HL-LHC experiments.

Charge Collection Efficiency Simulations of Irradiated Silicon Strip Detectors

CERN Document Server

Peltola, T.

2014-01-01

During the scheduled high luminosity upgrade of LHC, the world's largest particle physics accelerator at CERN, the position sensitive silicon detectors installed in the vertex and tracking part of the CMS experiment will face more intense radiation environment than the present system was designed for. Thus, to upgrade the tracker to required performance level, comprehensive measurements and simulations studies have already been carried out. Essential information of the performance of an irradiated silicon detector is obtained by monitoring its charge collection efficiency (CCE). From the evolution of CCE with fluence, it is possible to directly observe the effect of the radiation induced defects to the ability of the detector to collect charge carriers generated by traversing minimum ionizing particles (mip). In this paper the numerically simulated CCE and CCE loss between the strips of irradiated silicon strip detectors are presented. The simulations based on Synopsys Sentaurus TCAD framework were performed ...

MCNPX calculations for electron irradiated semiconductor detectors

International Nuclear Information System (INIS)

Sedlackova, K.; Necas, V.; Sagatova, A.; Zatko, B.

2014-01-01

This study aimed to treat some practical problems of (not only) semiconductor material irradiation by high energy electron beam using MCNPX simulation code. The relation between the absorbed dose and the fluency was found and the energy distribution of electron flux density was simulated on the top and back side of 270 μm thick GaAs, SiC and Si detectors. Furthermore, the dose depth profiles were calculated for GaAs, SiC and Si materials irradiated by 4 and 5 MeV electron beams. For the GaAs detector, a very good agreement with the experiment was shown. To match the absolute values of the absorbed dose with experimentally obtained values, the electron source emissivity has to be determined in relation to the electron beam setting parameters. (authors)

Charge collection in Si detectors irradiated in situ at superfluid helium temperature

Science.gov (United States)

Verbitskaya, Elena; Eremin, Vladimir; Zabrodskii, Andrei; Dehning, Bernd; Kurfürst, Christoph; Sapinski, Mariusz; Bartosik, Marcin R.; Egorov, Nicolai; Härkönen, Jaakko

2015-10-01

Silicon and diamond detectors operated in a superfluid helium bath are currently being considered for the upgrade of the LHC beam loss monitoring system. The detectors would be installed in immediate proximity of the superconducting coils of the triplet magnets. We present here the results of the in situ irradiation test for silicon detectors using 23 GeV protons while keeping the detectors at a temperature of 1.9 K. Red laser (630 nm) Transient Current Technique and DC current measurements were used to study the pulse response and collected charge for silicon detectors irradiated to a maximum radiation fluence of 1×1016 p/cm2. The dependence between collected charge and irradiation fluence was parameterized using the Hecht equation and assumption of a uniform electric field distribution. The collected charge was found to degrade with particle fluence for both bias polarities. We observed that the main factor responsible for this degradation was related to trapping of holes on the donor-type radiation-induced defects. In contrast to expectations, along with formation of donors, acceptor-type defects (electron traps) are introduced into the silicon bulk. This suggests that the current models describing charge collection in irradiated silicon detectors require an extension for taking into account trapping at low temperatures with a contribution of shallow levels. New in situ irradiation tests are needed and planned now to extend statistics of the results and gain a deeper insight into the physics of low temperature detector operation in harsh radiation environment.

Electron dosimetry in irradiation processing with rad-hard diodes; Dosimetria de eletrons em processos de irradiacao com diodos resistentes a danos de radiacao

Energy Technology Data Exchange (ETDEWEB)

Santos, Thais Cavalheri dos

2012-07-01

This work had the aim of the development of dosimetric systems based on Si special diodes, resistant to radiation damage to online monitoring of irradiation processing using 1.5 MeV electrons energy and for relative dosimetry and clinical electron beam scanning within an energy range of 6 MeV up to 21 MeV. The diodes used were produced by Float Zone standard (FZ), Magnetic Czochralski (MCz) and epitaxy growth (EPI) methods. In order to use the diodes as detectors, they were fixed on alumina base to allow the connection of the polarization electrodes and the signals extraction. After the diode assembly on the base, each one was housed in a black acrylic probe with aluminized Mylar Registered-Sign window and LEMO Registered-Sign connector. With the devices operating in photovoltaic mode, the integration of the current signals as a function of irradiation time allowed obtain the charge produced in the sensitive volume of each diode irradiated. The electron accelerator used for high doses irradiation was the DC 1500/25/4 JOB 188 of the 1.5 MeV installed at the Radiation Technology Center of the IPEN/CNEN-SP. The current profile as function of exposure time, the response repeatability, the sensitivity as function of absorbed dose and the dose response curve were studied for each device. In comparison to FZ diode, we observed a greater decrease in the sensitivity for MCz diode, and good repeatability in both cases. Also, the increasing of the charge with the absorbed dose was well fitted by a second order polynomial function. In the EPI diode characterization, this one exhibited repeatability better than CTA dosimeters applied routinely in radiation processing. The above results indicate the potential use of these radiation hardness Si diodes in online dosimetry to high doses applications. For low doses irradiation were used the linear accelerators KD2 and Primus, both manufactured by Siemens and located at Sirio-Libanes Hospital. The diodes responses were evaluated for

Charge collection in Si detectors irradiated in situ at superfluid helium temperature

Energy Technology Data Exchange (ETDEWEB)

Verbitskaya, Elena, E-mail: elena.verbitskaya@cern.ch [Ioffe Institute, 26 Politekhnicheskaya str., St. Petersburg 194021 (Russian Federation); Eremin, Vladimir; Zabrodskii, Andrei [Ioffe Institute, 26 Politekhnicheskaya str., St. Petersburg 194021 (Russian Federation); Dehning, Bernd; Kurfürst, Christoph; Sapinski, Mariusz; Bartosik, Marcin R. [CERN, CH-1211, Geneva 23 (Switzerland); Egorov, Nicolai [Research Institute of Material Science and Technology, 4 Passage 4806, Moscow, Zelenograd 124460 (Russian Federation); Härkönen, Jaakko [Helsinki Institute of Physics, P.O.Box 64 (Gustaf Hallströmin katu 2) FI-00014 University of Helsinki (Finland)

2015-10-01

Silicon and diamond detectors operated in a superfluid helium bath are currently being considered for the upgrade of the LHC beam loss monitoring system. The detectors would be installed in immediate proximity of the superconducting coils of the triplet magnets. We present here the results of the in situ irradiation test for silicon detectors using 23 GeV protons while keeping the detectors at a temperature of 1.9 K. Red laser (630 nm) Transient Current Technique and DC current measurements were used to study the pulse response and collected charge for silicon detectors irradiated to a maximum radiation fluence of 1×10{sup 16} p/cm{sup 2}. The dependence between collected charge and irradiation fluence was parameterized using the Hecht equation and assumption of a uniform electric field distribution. The collected charge was found to degrade with particle fluence for both bias polarities. We observed that the main factor responsible for this degradation was related to trapping of holes on the donor-type radiation-induced defects. In contrast to expectations, along with formation of donors, acceptor-type defects (electron traps) are introduced into the silicon bulk. This suggests that the current models describing charge collection in irradiated silicon detectors require an extension for taking into account trapping at low temperatures with a contribution of shallow levels. New in situ irradiation tests are needed and planned now to extend statistics of the results and gain a deeper insight into the physics of low temperature detector operation in harsh radiation environment. - Highlights: • Si detectors irradiated in situ at 1.9 K by 23 GeV protons are further studied. • Trapping parameters are derived from the fits of collected charge vs. fluence data. • Acceptor-type defects are likely to be induced along with donor-type ones. • Trapping of holes has a dominating effect on the collected charge degradation. • New tests are planned to gain deeper insight

UV-irradiation effects on polyester nuclear track detector

International Nuclear Information System (INIS)

Agarwal, Chhavi; Kalsi, P.C.

2010-01-01

The effects of UV irradiation (λ=254 nm) on polyester nuclear track detector have been investigated employing bulk-etch technique, UV-visible spectrophotometry and infra-red spectrometry (FTIR). The activation energy values for bulk-etching were found to decrease with the UV-irradiation time indicating the scission of the polymer. Not much shift in the absorption edge due to UV irradiation was seen in the UV-visible spectra. FTIR studies also indicate the scission of the chemical bonds, thereby further validating the bulk-etch rate results.

The effect of charge collection recovery in silicon p-n junction detectors irradiated by different particles

International Nuclear Information System (INIS)

Verbitskaya, E.; Abreu, M.; Anbinderis, P.; Anbinderis, T.; D'Ambrosio, N.; Boer, W. de; Borchi, E.; Borer, K.; Bruzzi, M.; Buontempo, S.; Casagrande, L.; Chen, W.; Cindro, V.; Dezillie, B.; Dierlamm, A.; Eremin, V.; Gaubas, E.; Gorbatenko, V.; Granata, V.; Grigoriev, E.; Grohmann, S.; Hauler, F.; Heijne, E.; Heising, S.; Hempel, O.; Herzog, R.; Haerkoenen, J.; Ilyashenko, I.; Janos, S.; Jungermann, L.; Kalesinskas, V.; Kapturauskas, J.; Laiho, R.; Li, Z.; Mandic, I.; De Masi, Rita; Menichelli, D.; Mikuz, M.; Militaru, O.; Niinikoski, T.O.; O'Shea, V.; Pagano, S.; Palmieri, V.G.; Paul, S.; Perea Solano, B.; Piotrzkowski, K.; Pirollo, S.; Pretzl, K.; Rato Mendes, P.; Ruggiero, G.; Smith, K.; Sonderegger, P.; Sousa, P.; Tuominen, E.; Vaitkus, J.; Da Via, C.; Wobst, E.; Zavrtanik, M.

2003-01-01

The recovery of the charge collection efficiency (CCE) at low temperatures, the so-called 'Lazarus effect', was studied in Si detectors irradiated by fast reactor neutrons, by protons of medium and high energy, by pions and by gamma-rays. The experimental results show that the Lazarus effect is observed: (a) after all types of irradiation; (b) before and after space charge sign inversion; (c) only in detectors that are biased at voltages resulting in partial depletion at room temperature. The experimental temperature dependence of the CCE for proton-irradiated detectors shows non-monotonic behaviour with a maximum at a temperature defined as the CCE recovery temperature. The model of the effect for proton-irradiated detectors agrees well with that developed earlier for detectors irradiated by neutrons. The same midgap acceptor-type and donor-type levels are responsible for the Lazarus effect in detectors irradiated by neutrons and by protons. A new, abnormal 'zigzag'-shaped temperature dependence of the CCE was observed for detectors irradiated by all particles (neutrons, protons and pions) and by an ultra-high dose of γ-rays, when operating at low bias voltages. This effect is explained in the framework of the double-peak electric field distribution model for heavily irradiated detectors. The redistribution of the space charge region depth between the depleted regions adjacent to p + and n + contacts is responsible for the 'zigzag'- shaped curves. It is shown that the CCE recovery temperature increases with reverse bias in all detectors, regardless of the type of radiation

RD50 recent results: Development of radiation hard sensors for SLHC

CERN Document Server

Macchiolo, Anna

2009-01-01

The need for radiation hard semiconductor detectors for the tracker regions in high energy physics experiments at a future high luminosity hadron collider, like the proposed LHC upgrade, has led to the formation of the CERN RD50 collaboration. The R&D directions of RD50 follow two paths: the optimization of radiation hard bulk materials (Material Engineering) and the development of new detector designs (Device Engineering) as 3D sensors, thin sensors and n-in-p sensors. Some of the RD50 most recent results about silicon detectors are reported in this paper, with special reference to: (i) identification of defects responsible for long term annealing, (ii) charge collection efficiency of irradiated planar devices, in particular n-in-p microstrip detectors and epitaxial diodes, (iii) charge collection efficiency of double-type column 3D detectors, (iv) comparison of the performances of FZ and MCZ structures under mixed irradiation.

Scanning transient current study of the I-V stabilization phenomena in silicon detectors irradiated by fast neutrons

International Nuclear Information System (INIS)

Eremin, V.; Verbitskaya, E.; Sidorov, A.; Fretwurst, E.; Lindstrom, G.

1996-03-01

Investigation of the I-V stabilization phenomena in neutron irradiated silicon detectors has been carried out using scanning transient current technique (STCT) on non-irradiated PP + -p-n + detectors. The PP + -p-n + detectors were used to simulate the PP + -n-n + detectors irradiated beyond the space charge sign inversion (SCSI). Two mechanisms partially responsible for the I- V stabilization have been identified

Characterisation of an inhomogeneously irradiated microstrip detector using a fine spot infrared laser

CERN Document Server

Casse, G; Bowcock, T J V; Greenall, A; Phillips, JP; Turner, PR; Wright, V

2001-01-01

A prototype silicon microstrip detector for the LHCb vertex locator (VELO) has been partially irradiated using a 24 GeV/c proton beam at the CERN-PS accelerator. The detector possesses a radial strip geometry designed to measure the azimuthal coordinate (Phi) of tracks within the VELO. The peak fluence received by the detector was measured to be 4.6×10 14 p/cm 2 though the non-uniform nature of the exposure left part of the detector unirradiated. The inhomogeneous irradiation introduced a damage profile in the detector approximating to that expected in the VELO. High irradiation gradients are important to study as they can modify the electric field within the silicon. Of special interest are changes in the component of the electric field parallel to the strip plane but perpendicular to the strips which lead to systematic shifts in the reconstructed cluster position. If these (flux and position dependent) shifts are sufficiently large they could contribute to a degraded spatial resolution of the detector. In ...

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.

Developing a fast simulator for irradiated silicon detectors

CERN Document Server

Diez Gonzalez-Pardo, Alvaro

2015-01-01

Simulation software for irradiated silicon detectors has been developed on the basis of an already existing C++ simulation software called TRACS[1]. This software has been already proven useful in understanding non-irradiated silicon diodes and microstrips. In addition a wide variety of user-focus features has been implemented to improve on TRACS flexibility. Such features include an interface to allow any program to leverage TRACS functionalities, a configuration file and improved documentation.

Radiation damage of pixelated photon detector by neutron irradiation

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Isamu [KEK, 1-1 Oho Tsukuba 305-0801 (Japan)], E-mail: isamu.nakamura@kek.jp

2009-10-21

Radiation Damage of Pixelated Photon Detector by neutron irradiation is reported. MPPC, one of PPD or Geiger-mode APD, developed by Hamamatsu Photonics, is planned to be used in many high energy physics experiments. In such experiments radiation damage is a serious issue. A series of neutron irradiation tests is performed at the Reactor YAYOI of the University of Tokyo. MPPCs were irradiated at the reactor up to 10{sup 12}neutron/cm{sup 2}. In this paper, the effect of neutron irradiation on the basic characteristics of PPD including gain, noise rate, photon detection efficiency is presented.

Charge collection properties of heavily irradiated epitaxial silicon detectors

International Nuclear Information System (INIS)

Kramberger, G.; Cindro, V.; Dolenc, I.; Fretwurst, E.; Lindstroem, G.; Mandic, I.; Mikuz, M.; Zavrtanik, M.

2005-01-01

Detectors processed on epitaxial silicon seem to be a viable solution for the extreme radiation levels in the innermost layers of tracking detectors at upgraded LHC (SLHC). A set of epitaxial pad detectors of 50 and 75μm thicknesses (ρ=50Ωcm) was irradiated with 24GeV/c protons and reactor neutrons up to equivalent fluences of 10 16 cm -2 . Charge collection for minimum ionizing electrons from a 90 Sr source was measured using a charge sensitive preamplifier and a 25ns shaping circuit. The dependence of collected charge on annealing time and operation temperature was studied. Results were used to predict the performance of fine pitch pixel detectors proposed for SLHC

Charge collection properties of heavily irradiated epitaxial silicon detectors

Energy Technology Data Exchange (ETDEWEB)

Kramberger, G. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia)]. E-mail: Gregor.Kramberger@ijs.si; Cindro, V. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia); Dolenc, I. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia); Fretwurst, E. [University of Hamburg, Institut fuer Experimentalphysik, Luruper Chaussee 149, D-22761 Hamburg (Germany); Lindstroem, G. [University of Hamburg, Institut fuer Experimentalphysik, Luruper Chaussee 149, D-22761 Hamburg (Germany); Mandic, I. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia); Mikuz, M. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia); Zavrtanik, M. [Institute Jozef Stefan, Jamova 39, SI-1111 Ljubljana (Slovenia)

2005-12-01

Detectors processed on epitaxial silicon seem to be a viable solution for the extreme radiation levels in the innermost layers of tracking detectors at upgraded LHC (SLHC). A set of epitaxial pad detectors of 50 and 75{mu}m thicknesses ({rho}=50{omega}cm) was irradiated with 24GeV/c protons and reactor neutrons up to equivalent fluences of 10{sup 16}cm{sup -2}. Charge collection for minimum ionizing electrons from a {sup 90}Sr source was measured using a charge sensitive preamplifier and a 25ns shaping circuit. The dependence of collected charge on annealing time and operation temperature was studied. Results were used to predict the performance of fine pitch pixel detectors proposed for SLHC.

Charge collection and charge pulse formation in highly irradiated silicon planar detectors

International Nuclear Information System (INIS)

Dezillie, B.; Li, Z.; Eremin, V.

1998-06-01

The interpretation of experimental data and predictions for future experiments for high-energy physics have been based on conventional methods like capacitance versus voltage (C-V) measurements. Experiments carried out on highly irradiated detectors show that the kinetics of the charge collection and the dependence of the charge pulse amplitude on the applied bias are deviated too far from those predicted by the conventional methods. The described results show that in highly irradiated detectors, at a bias lower than the real full depletion voltage (V fd ), the kinetics of the charge collection (Q) contains a fast and a slow component. At V = V fd *, which is the full depletion voltage traditionally determined by the extrapolation of the fast component amplitude of q versus bias to the maximum value or from the standard C-V measurements, the pulse has a slow component with significant amplitude. This slow component can only be eliminated by applying additional bias that amounts to the real full depletion voltage (V fd ) or more. The above mentioned regularities are explained in this paper in terms of a model of an irradiated detector with multiple regions. This model allows one to use C-V, in a modified way, as well as TChT (transient charge technique) measurements to determine the V fd for highly irradiated detectors

A comprehensive analysis of irradiated silicon detectors at cryogenic temperatures

CERN Document Server

Santocchia, A; Hall, G; MacEvoy, B; Moscatelli, F; Passeri, D; Pignatel, Giogrio Umberto

2003-01-01

The effect of particle irradiation on high-resistivity silicon detectors has been extensively studied with the goal of engineering devices able to survive the very challenging radiation environment at the CERN Large Hadron Collider (LHC). The main aspect under investigation has been the changes observed in detector effective doping concentration (N/sub eff/). We have previously proposed a mechanism to explain the evolution of N/sub eff/, whereby charge is exchanged directly between closely-spaced defect centres in the dense terminal clusters formed by hadron irradiation. This model has been implemented in both a commercial finite-element device simulator (ISE-TCAD) and a purpose-built simulation of interdefect charge exchange. To control the risk of breakdown due to the high leakage currents foreseen during ten years of LHC operation, silicon detectors will be operated below room temperature (around -10 degrees C). This, and more general current interest in the field of cryogenic operation, has led us to inve...

Modeling of displacement damage in silicon carbide detectors resulting from neutron irradiation

Science.gov (United States)

Khorsandi, Behrooz

There is considerable interest in developing a power monitor system for Generation IV reactors (for instance GT-MHR). A new type of semiconductor radiation detector is under development based on silicon carbide (SiC) technology for these reactors. SiC has been selected as the semiconductor material due to its superior thermal-electrical-neutronic properties. Compared to Si, SiC is a radiation hard material; however, like Si, the properties of SiC are changed by irradiation by a large fluence of energetic neutrons, as a consequence of displacement damage, and that irradiation decreases the life-time of detectors. Predictions of displacement damage and the concomitant radiation effects are important for deciding where the SiC detectors should be placed. The purpose of this dissertation is to develop computer simulation methods to estimate the number of various defects created in SiC detectors, because of neutron irradiation, and predict at what positions of a reactor, SiC detectors could monitor the neutron flux with high reliability. The simulation modeling includes several well-known---and commercial---codes (MCNP5, TRIM, MARLOWE and VASP), and two kinetic Monte Carlo codes written by the author (MCASIC and DCRSIC). My dissertation will highlight the displacement damage that may happen in SiC detectors located in available positions in the OSURR, GT-MHR and IRIS. As extra modeling output data, the count rates of SiC for the specified locations are calculated. A conclusion of this thesis is SiC detectors that are placed in the thermal neutron region of a graphite moderator-reflector reactor have a chance to survive at least one reactor refueling cycle, while their count rates are acceptably high.

Proton Irradiation of CVD Diamond Detectors for High Luminosity Experiments at the LHC

CERN Document Server

Meier, D; Bauer, C; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; 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; Jany, C; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Knöpfle, K T; Krammer, Manfred; Manfredi, P F; Marshall, R D; Mishina, M; Le Normand, F; Pan, L S; Palmieri, V G; Pernegger, H; Pernicka, Manfred; Peitz, A; Pirollo, S; 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; Turchetta, R; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zöller, M

1999-01-01

CVD diamond shows promising properties for use as a position sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardn ess of diamond we exposed CVD diamond detector samples to 24~GeV/$c$ and 500~MeV protons up to a fluence of $5\\times 10^{15}~p/{\\rm cm^2}$. We measured the charge collection distance, the ave rage distance electron hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to $1\\ times 10^{15}~p/{\\rm cm^2}$ and decreases by $\\approx$40~\\% at $5\\times 10^{15}~p/{\\rm cm^2}$. Leakage currents of diamond samples were below 1~pA before and after irradiation. The particle indu ced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage curren t. We conclude that CVD diamond detectors are radia...

Charge collection efficiency of irradiated silicon detector operated at cryogenic temperatures

International Nuclear Information System (INIS)

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

2000-01-01

The charge collection efficiency (CCE) of heavily irradiated silicon diode detectors was investigated at temperatures between 77 and 200 K. The CCE was found to depend on the radiation dose, bias voltage value and history, temperature, and bias current generated by light. The detector irradiated to the highest fluence 2x10 15 n/cm 2 yields a MIP signal of at least 15000 e - both at 250 V forward bias voltage, and at 250 V reverse bias voltage in the presence of a light-generated current. The 'Lazarus effect' was thus shown to extend to fluences at least ten times higher than was previously studied

Proton irradiation of CVD diamond detectors for high-luminosity experiments at the LHC

Science.gov (United States)

Meier, D.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Foulon, F.; Friedl, M.; Jany, C.; 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.; Krammer, M.; Manfredi, P. F.; Marshall, R. D.; Mishina, M.; Le Normand, F.; Pan, L. S.; Palmieri, V. G.; Pernegger, H.; Pernicka, M.; Peitz, A.; Pirollo, S.; 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.; Turchetta, R.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.; RD42 Collaboration

1999-04-01

CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/ c and 500 Mev protons up to a fluence of 5×10 15 p/cm 2. We measured the charge collection distance, the average distance electron-hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1×10 15 p/cm 2 and decreases by ≈40% at 5×10 15 p/cm 2. Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/ c and 500 MeV protons up to at least 1×10 15p/cm 2 without signal loss.

Proton irradiation of CVD diamond detectors for high-luminosity experiments at the LHC

International Nuclear Information System (INIS)

Meier, D.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Foulon, F.; Friedl, M.; Jany, C.; 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.; Knoepfle, K.T.; Krammer, M.; Manfredi, P.F.; Marshall, R.D.; Mishina, M.; Le Normand, F.; Pan, L.S.; Palmieri, V.G.; Pernegger, H.; Pernicka, M.; Peitz, A.; Pirollo, S.; 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.; Turchetta, R.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.

1999-01-01

CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/c and 500 Mev protons up to a fluence of 5x10 15 p/cm 2 . We measured the charge collection distance, the average distance electron-hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1x10 15 p/cm 2 and decreases by ∼40% at 5x10 15 p/cm 2 . Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/c and 500 MeV protons up to at least 1x10 15 p/cm 2 without signal loss

High irradiation and ageing properties of resistive Micromegas detectors at the new CERN Gamma Irradiation Facility

CERN Document Server

Andreou, Dimitra

2016-01-01

Resistive Micromegas have been developed in recent years with the aim of making this technology usable in HEP experiments where the high sparking rate of classical Micromegas is not tolerable. A resistive Micromegas with four layers and an active surface of 0.5 m2 each, has been designed and built at CERN as prototype of the detectors to be used for the upgrade of the ATLAS experiment. The detector has been exposed to an intense gamma source of 16 TBq in order to study the effects of ageing and evaluate the detector behavior under high irradiation.

Gamma and electron high dose dosimetry with rad-hard Si diodes

International Nuclear Information System (INIS)

Pascoalino, Kelly Cristina da Silva

2014-01-01

In this work the main dosimetric characteristics of rad-hard Float Zone (FZ) and magnetic Czochralski (MCz) diodes to electrons (1.5 MeV) and gamma ( 60 Co) radiation are evaluated. The dosimetric system proposed is based on electrical current measurements due to radiation interactions on the devices. The batch response uniformity was studied for the n-type FZ diodes irradiated with gamma rays. The coefficient of variation of the current measurement was about 1.25% at 5 kGy of accumulated dose. A sensitivity decrease with the increase of the accumulated dose (Total Ionizing Dose - TID) was observed for both FZ and MCz diodes. For gamma irradiation, these effect is more pronounced for n-type or smaller resistivity diodes. Two types of dosimetric probe were used on the electron irradiation procedures, one of them specially designed to avoid the deterioration of the electrical contacts and the diodes metallization. The sensitivity of the preirradiated FZ and MCz diodes fell about 10% and 40%, respectively, during electron irradiation at 1.25 MGy of accumulated dose. The effect of electron radiation damage on the electrical properties of the diodes was studied by the means of leakage current and capacitance measurements as a function of bias voltage. The leakage current increases with the accumulated dose but does not contributes significantly to the current signal, since the diodes are operated in photovoltaic mode, without bias voltage. For the MCz diode no change in the full depletion voltage was observed, which indicates its higher tolerance to radiation-induced damage, as expected. During electron irradiation the temperature increases and in order to determine its influence for the current signals, the leakage current values were extrapolated up to 35 °C. The contribution does not exceed 0.1% for FZ and MCz diodes. The effect of the radiation type, electrons or gamma rays, on the pre dose procedures was analyzed for the FZ n-type device and was observed that the

Testbeam and laboratory test results of irradiated 3D CMS pixel detectors

Energy Technology Data Exchange (ETDEWEB)

Bubna, Mayur [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Purdue University, School of Electrical and Computer Engineering, West Lafayette, IN 47907-1396 (United States); Alagoz, Enver, E-mail: enver.alagoz@cern.ch [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Cervantes, Mayra; Krzywda, Alex; Arndt, Kirk [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Obertino, Margherita; Solano, Ada [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, 10125 Torino (Italy); Dalla Betta, Gian-Franco [INFN Padova (Gruppo Collegato di Trento) (Italy); Dipartimento di Ingegneria e Scienzadella Informazione, Universitá di Trento, I-38123 Povo di Trento (Italy); Menace, Dario; Moroni, Luigi [Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca (Italy); Universitá degli Studi di Milano Bicocca, 20126 Milano (Italy); Uplegger, Lorenzo; Rivera, Ryan [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Osipenkov, Ilya [Texas A and M University, Department of Physics, College Station, TX 77843-4242 (United States); Andresen, Jeff [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Bolla, Gino; Bortoletto, Daniela [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Boscardin, Maurizio [Centro per i Materiali e i Microsistemi Fondazione Bruno Kessler (FBK), Trento, I-38123 Povo di Trento (Italy); Marie Brom, Jean [Strasbourg IPHC, Institut Pluriedisciplinaire Hubert Curien, F-67037 Strasbourg Cedex (France); Brosius, Richard [State University of New York at Buffalo (SUNY), Department of Physics, Buffalo, NY 14260-1500 (United States); Chramowicz, John [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); and others

2013-12-21

The CMS silicon pixel detector is the tracking device closest to the LHC p–p collisions, which precisely reconstructs the charged particle trajectories. The planar technology used in the current innermost layer of the pixel detector will reach the design limit for radiation hardness at the end of Phase I upgrade and will need to be replaced before the Phase II upgrade in 2020. Due to its unprecedented performance in harsh radiation environments, 3D silicon technology is under consideration as a possible replacement of planar technology for the High Luminosity-LHC or HL-LHC. 3D silicon detectors are fabricated by the Deep Reactive-Ion-Etching (DRIE) technique which allows p- and n-type electrodes to be processed through the silicon substrate as opposed to being implanted through the silicon surface. The 3D CMS pixel devices presented in this paper were processed at FBK. They were bump bonded to the current CMS pixel readout chip, tested in the laboratory, and testbeams carried out at FNAL with the proton beam of 120 GeV/c. In this paper we present the laboratory and beam test results for the irradiated 3D CMS pixel devices. -- Highlights: •Pre-irradiation and post-irradiation electrical properties of 3D sensors and 3D diodes from various FBK production batches were measured and analyzed. •I–T measurements of gamma irradiated diodes were analyzed to understand leakage current generation mechanism in 3D diodes. •Laboratory measurements: signal to noise ratio and charge collection efficiency of 3D sensors before and after irradiation. •Testbeam measurements: pre- and post-irradiation pixel cell efficiency and position resolution of 3D sensors.

A normalization of the physical tests for external irradiation measuring detectors

International Nuclear Information System (INIS)

1977-05-01

This report is the result of a normalization work, realized within the Radioprotection Services of the C.E.A., of the physical tests for detectors measuring external irradiation. Among the various tests mentionned are treated more in details, calibration and the establishment of the relative spectral response. As far as calibration is concerned, the normalization refers to: the reference detector, the reference radiation source, the installation and calibration procedure. As for the relative spectral response the normalization refers to: the reference detector, the radiation sources to be used. Finally, a chapter is consecrated to the high flux detectors and to those for pulsed electromagnetic radiations [fr

Proton irradiation of CVD diamond detectors for high-luminosity experiments at the LHC

Energy Technology Data Exchange (ETDEWEB)

Meier, D. E-mail: dirk.meier@cern.ch.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Foulon, F.; Friedl, M.; Jany, C.; 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.; Knoepfle, K.T.; Krammer, M.; Manfredi, P.F.; Marshall, R.D.; Mishina, M.; Le Normand, F.; Pan, L.S.; Palmieri, V.G.; Pernegger, H.; Pernicka, M.; Peitz, A.; Pirollo, S.; 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.; Turchetta, R.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M

1999-04-21

CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/c and 500 Mev protons up to a fluence of 5x10{sup 15} p/cm{sup 2}. We measured the charge collection distance, the average distance electron-hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1x10{sup 15} p/cm{sup 2} and decreases by {approx}40% at 5x10{sup 15} p/cm{sup 2}. Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/c and 500 MeV protons up to at least 1x10{sup 15}p/cm{sup 2} without signal loss.

The effect of ArF laser irradiation (193 nm) on the photodegradation and etching properties of alpha-irradiated CR-39 detectors

Energy Technology Data Exchange (ETDEWEB)

Shakeri Jooybari, B. [Department of Energy Engineering and Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Nuclear Science and Technology Research Institute (NSRT), Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Ghergherehchi, M. [College of Information and Technology/ school of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon (Korea, Republic of); Afarideh, H., E-mail: hafarideh@aut.ac.ir [Department of Energy Engineering and Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Lamehi-Rachti, M. [Nuclear Science and Technology Research Institute (NSRT), Tehran, Islamic Republic of Iran (Iran, Islamic Republic of)

2015-01-01

The effects of ArF laser irradiation (λ=193nm) at various fluences (energy dose or energy density) on the etching properties of pre-exposed (laser + alpha) CR-39 detectors were studied. First, UV–Vis and Fourier transform infrared (FTIR) spectra were acquired for non-laser-irradiated and laser-irradiated samples to detect the influence of the ArF laser on the chemical modification of the CR-39. Changes observed in the spectra indicated that the predominant process that occurred upon ArF laser irradiation was a bond-scission process. Thereafter, the mean track and bulk etching parameters were experimentally measured in ArF-laser-irradiated CR-39 detectors exposed to an alpha source ({sup 241}Am, E = 5.49 MeV). Inhomogeneous regions in the laser-irradiated side of the CR-39 demonstrated a variable etching rate on only the front side of the CR-39 detector. New equations are also presented for the average bulk etching rate for these inhomogeneous regions (front side). The mean bulk and track etching rates and the mean track dimensions increased in a fluence range of 0–37.03 mJ/cm{sup 2} because of photodegradation and the scission of chemical bonds, which are the predominant processes in this range. When the fluence was increased from 37.03 to 123.45 mJ/cm{sup 2}, the bulk and track etching rates and the track dimensions slowly decreased because of the formation of cross-linked structures on the CR-39 surface. The behavior of the bulk and track etching rates and the track dimensions appears to be proportional to the dose absorbed on the detector surface. It was observed that as the etching time was increased, the bulk and track etching rates and the track dimensions of the laser-irradiated samples decreased because of the shallow penetration depth of the 193 nm laser and the reduction in the oxygen penetration depth.

TOSCA simulation of some effects observed in irradiated silicon detectors

International Nuclear Information System (INIS)

Moszczynski, A.S.

2001-12-01

TOSCA package has been used to simulate some effects observed recently in heavily irradiated silicon detectors. In particular, unexpected possibility of α-particle registration at p+ contact has been explained without presented elsewhere assumption that there was p-n junction of unknown origin beneath p+ layer. Performed simulations showed that assumption on relaxation-like character of irradiated silicon material is also not necessary to explain such effects like low-voltage capacitance peak in reverse bias and negative capacitance in forward bias. (author)

A standardization of the physical tests for external irradiation measuring detectors

International Nuclear Information System (INIS)

1977-05-01

This report is the result of a standardization work, realized within the Radioprotection Services of the A.E.C., of the physical tests for dectors measuring external irradiations. Among the various tests mentionned, calibration and the establishment of the relative spectral response are treated in details. As far as calibration is concerned, the standardization refers to: the reference detector, the reference radiation source, the installation and calibration procedure. As for the relative spectral response the standardization refers to: the reference detector, the radiation sources to be used. High flux detectors and those for pulse electromagnetic radiations are also dealt with [fr

Suppression of irradiation effects in gold-doped silicon detectors

International Nuclear Information System (INIS)

McPherson, M.; Sloan, T.; Jones, B.K.

1997-01-01

Two sets of silicon detectors were irradiated with 1 MeV neutrons to different fluences and then characterized. The first batch were ordinary p-i-n photodiodes fabricated from high-resistivity (400 Ω cm) silicon, while the second batch were gold-doped powder diodes fabricated from silicon material initially of low resistivity (20 Ω cm). The increase in reverse leakage current after irradiation was found to be more in the former case than in the latter. The fluence dependence of the capacitance was much more pronounced in the p-i-n diodes than in the gold-doped diodes. Furthermore, photo current generation by optical means was less in the gold doped devices. All these results suggest that gold doping in silicon somewhat suppresses the effects of neutron irradiation. (author)

Beam test results of the irradiated Silicon Drift Detector for ALICE

OpenAIRE

Kushpil, S.; Crescio, E.; Giubellino, P.; Idzik, M.; Kolozhvari, A.; Kushpil, V.; Martinez, M. I.; Mazza, G.; Mazzoni, A.; Meddi, F.; Nouais, D.; Petracek, V.; Piemonte, C.; Rashevsky, A.; Riccati, L.

2005-01-01

The Silicon Drift Detectors will equip two of the six cylindrical layers of high precision position sensitive detectors in the ITS of the ALICE experiment at LHC. In this paper we report the beam test results of a SDD irradiated with 1 GeV electrons. The aim of this test was to verify the radiation tolerance of the device under an electron fluence equivalent to twice particle fluence expected during 10 years of ALICE operation.

Dose Response of Alanine Detectors Irradiated with Carbon Ion Beams

DEFF Research Database (Denmark)

Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo

2011-01-01

Purpose: The dose response of the alanine detector shows a dependence on particle energy and type, when irradiated with ion beams. The purpose of this study is to investigate the response behaviour of the alanine detector in clinical carbon ion beams and compare the results with model predictions......-dose curves deviate from predictions in the peak region, most pronounced at the distal edge of the peak. Conclusions: The used model and its implementation show a good overall agreement for quasi mono energetic measurements. Deviations in depth-dose measurements are mainly attributed to uncertainties...

Evidence for plasma effect on charge collection efficiency in proton irradiated GaAs detectors

CERN Document Server

Nava, F; Canali, C; Vittone, E; Polesello, P; Biggeri, U; Leroy, C

1999-01-01

The radiation damage in 100 mu m thick Schottky diodes made on semi-insulating undoped GaAs materials, were studied using alpha-, beta-, proton- and gamma-spectroscopy as well as I-V measurements. The results have been analysed within the framework of the Hecht model to investigate the influence of the plasma produced by short-range strongly ionising particles on the detector performance after 24 GeV proton irradiation. It has been found that with the mean free drift lengths for electrons and holes determined from alpha-spectra in overdepleted detectors, the charge collection efficiency for beta-particles, cce subbeta, is well predicted in the unirradiated detectors, while in the most irradiated ones, the cce subbeta is underestimated by more than 40%. The observed disagreement can be explained by assuming that the charge carrier recombination in the plasma region of such detectors, becomes significant.

Signal generation in highly irradiated silicon microstrip detectors for the ATLAS experiment

International Nuclear Information System (INIS)

Ruggiero, Gennaro

2003-01-01

Silicon detectors are the most diffused tracking devices in High Energy Physics (HEP). The reason of such success can be found in the characteristics of the material together with the existing advanced technology for the fabrication of these devices. Nevertheless in many modem HEP experiments the observation of vary rare events require data taking at high luminosity with a consequent extremely intense hadron radiation field that damages the silicon and degrades the performance of these devices. In this thesis work a detailed study of the signal generation in microstrip detectors has been produced with a special care for the ATLAS semiconductor tracker geometry. This has required a development of an appropriate setup to perform measurements with Transient Current/ Charge Technique. This has allowed studying the evolution of the signal in several microstrips detector samples irradiated at fluences covering the range expected in the ATLAS Semiconductor Tracker. For a better understanding of these measurements a powerful software package that simulates the signal generation in these devices has been developed. Moreover in this thesis it has been also shown that the degradation due to radiation in silicon detectors can be strongly reduced if the data taking is done with detectors operated at 130 K. This makes low temperature operation that benefits of the recovery of the charge collection efficiency in highly irradiated silicon detectors (also known as Lazarus effect) an optimal option for future high luminosity experiments. (author)

Fast neutron irradiation effects on CR-39 nuclear track detector for dosimetric applications

International Nuclear Information System (INIS)

Kader, M.H.

2005-01-01

The effect of neutron irradiation on the dosimetric properties of CR-39 solid-state nuclear track detector have been investigated. CR-39 samples were irradiated with neutrons of energies follow a Maxwellian distribution centered about 2 MeV. These samples were irradiated with different doses in the range 0.1-1 Sv. The background and track density were measured as a function of etching time. In addition, the dependence of sensitivity of CR-39 detector on the neutrons dose has been investigated. The results show that the Sensitivity started to increase at 0.4 Sv neutrons dose, so this sample were chosen to be a subject for further study to investigate the effect of gamma dose on its properties. The sample irradiated with 0.4 Sv were exposed to different doses of gamma rays at levels between 10 and 80 kGy. The effect of gamma doses on the bulk etching rate VB, the track diameter and the sensitivity of the CR-39 samples was investigated. The results show that the dosimetric properties of CR-39 SSNTD are greatly affected by both neutron and gamma irradiation

Opto-structural characterization of gamma irradiated Bayfol polymer track detector

Energy Technology Data Exchange (ETDEWEB)

Tayel, A. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Zaki, M.F., E-mail: moha1016@yahoo.com [Experimental Nuclear Physics Department, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Abu Zaabal, Cairo (Egypt); El Basaty, A.B. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Hegazy, Tarek M. [Physics Department, College of Women for Arts, Science and Education, Ain Shams University, Cairo (Egypt)

2013-11-15

Bayfol CR 1-4 is one of polymeric solid state nuclear track detector which has numerous applications due to its outstanding optical, mechanical, thermal and electrical properties. In the present study, Bayfol polymer is irradiated with different doses of gamma rays ranging from 0 to 1000 KGy. The effects of gamma irradiations on the optical, structural and chemical properties of Bayfol were studied using Ultraviolet and visible (UV/Vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The UV–Vis spectra of irradiated samples show that the absorption edge is shifted towards longer wavelength comparing to pristine sample spectrum. This behavior indicates that there is a decrease in the band gap after irradiation. The maximum decrease in the band gap is about 0.8 eV. The XRD patterns of amorphous halo of pristine and irradiated samples show a fluctuation of integrated intensity of amorphous halo. This indicates a change in the structure due to gamma irradiation. In order to understand that structure change mechanism, we used the FTIR spectroscopy.

Influence for high intensity irradiation on characteristics of silicon strip-detectors

International Nuclear Information System (INIS)

Anokhin, I.E.; Pugatch, V.M.; Zinets, O.S.

1995-01-01

Full text: Silicon strip detectors (SSD) are widely used for the coordinate determination of short-range as well as minimum ionizing particles with high spatial resolution. Submicron position sensitivity of strip-detectors for short-range particles has been studied by means of two dimensional analyses of charges collected by neighboring strips as well as by measurement of charge collection times [1]. Silicon strip detectors was also used for testing high energy electron beam [2]. Under large fluences the radiation defects are stored and such characteristics of strip-detectors as an accuracy of the coordinate determination and the registration efficiency are significantly changed. Radiation defects lead to a decrease of the lifetime and mobility of charge carriers and therefore to changes of conditions for the charge collection in detectors. The inhomogeneity in spatial distribution if defects and electrical field plays an important role in the charge collection. In this report the role of the diffusion and drift in the charge collection in silicon strip-detectors under irradiation up to 10 Mrad has been studied. The electric field distribution and its dependence on the radiation dose in the detector have been calculated. It is shown that for particles incident between adjacent strips the coordinate determination precision depends strongly on the detector geometry and the electric field distribution, particularly in the vicinity of strips. Measuring simultaneously the collected charges and collection times on adjacent strips one can essentially improve reliability of the coordinate determination for short-range particles. Usually SSD are fabricated on n-type wafers. It is well known that under high intensity irradiation n-Si material converts into p-Si as far as p-type silicon is more radiative hard than n-type silicon [3] it is reasonable to fabricate SSD using high resistivity p-Si. Characteristics of SSD in basis n-and P-Si have been compared and higher

Simulation of medical irradiation and X-ray detector signals

Energy Technology Data Exchange (ETDEWEB)

Kreisler, Bjoern

2010-02-08

This thesis aims for an improved understanding of medical irradiation. Two major parts are investigated: the beam shaping components of a medical linear accelerator, i.e. the source of the radiation, and the signal generation inside semiconductor sensors, i.e. the detection of the radiation. The direct measurement of the spatial and spectral particle distribution in the irradiation beam is not possible with state of the art detectors due to the high particle flux. The development of new advanced detectors is the goal of the first part of this thesis. The focus is set on the signal generation inside the sensor volume of a semiconductor detector. Incoming particles interact with the sensor material and generate clouds of electron hole pairs. These pairs get separated by an applied bias voltage. The motion of the charge clouds is simulated with a finite element programme taking into account the drift and diffusion. Mirror charges are induced on the electrodes which move due to the motion of the charge cloud. The motion of the induced mirror charges leads to the signal that is detected. The transient calculation of the signals is based on Ramo's theorem. The efficient adjoint formulation of the induction solution is adjusted to doped materials, as for example the electric bias field and hence the motion of the charge cloud is changing with the doping level. The effect of the doping of the material on the signal shape is shown together with influences of different voltages and pixel geometries. Smaller pixels and higher bias voltages can lead to shorter signals which is preferable for high flux measurements. Possible count rate improvements are limited by electric break through, high dark current across the sensor layer and charge sharing. Another option to shorten the signals is the use of steering grid electrodes which modify the electric and the weighting field. This results in shorter signals and thus in a higher possible rate. The detailed Monte

Simulation of medical irradiation and X-ray detector signals

International Nuclear Information System (INIS)

Kreisler, Bjoern

2010-01-01

This thesis aims for an improved understanding of medical irradiation. Two major parts are investigated: the beam shaping components of a medical linear accelerator, i.e. the source of the radiation, and the signal generation inside semiconductor sensors, i.e. the detection of the radiation. The direct measurement of the spatial and spectral particle distribution in the irradiation beam is not possible with state of the art detectors due to the high particle flux. The development of new advanced detectors is the goal of the first part of this thesis. The focus is set on the signal generation inside the sensor volume of a semiconductor detector. Incoming particles interact with the sensor material and generate clouds of electron hole pairs. These pairs get separated by an applied bias voltage. The motion of the charge clouds is simulated with a finite element programme taking into account the drift and diffusion. Mirror charges are induced on the electrodes which move due to the motion of the charge cloud. The motion of the induced mirror charges leads to the signal that is detected. The transient calculation of the signals is based on Ramo's theorem. The efficient adjoint formulation of the induction solution is adjusted to doped materials, as for example the electric bias field and hence the motion of the charge cloud is changing with the doping level. The effect of the doping of the material on the signal shape is shown together with influences of different voltages and pixel geometries. Smaller pixels and higher bias voltages can lead to shorter signals which is preferable for high flux measurements. Possible count rate improvements are limited by electric break through, high dark current across the sensor layer and charge sharing. Another option to shorten the signals is the use of steering grid electrodes which modify the electric and the weighting field. This results in shorter signals and thus in a higher possible rate. The detailed Monte-Carlo simulation of

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...

Self-Powered Neutron Detector Calibration Using a Large Vertical Irradiation Hole of HANARO

Directory of Open Access Journals (Sweden)

Kim Myong-Seop

2018-01-01

Full Text Available A calibration technology of the self-powered neutron detectors (SPNDs using a large vertical irradiation hole of HANARO is developed. The 40 Rh-SPNDs are installed on the polycarbonate plastic support, and the gold wires with the same length as the effective length of the rhodium emitter of the SPND are also installed to measure the neutron flux on the SPND. They are irradiated at a low reactor power, and the SPND current is measured using the pico-ammeter. The external gamma-rays which affect the SPND current response are analyzed using the Monte Carlo simulation for various irradiation conditions in HANARO. It is confirmed that the effect of the external gamma-rays to the SPND current is dependent on the reactor characteristics, and that it is affected by materials around the detector. The current signals due to the external gamma-rays can be either positive or negative, in that the net flow of the current may be either in the same or the opposite direction as the neutron-induced current by the rhodium emitter. From the above procedure, the effective calibration methodology of multiple SPNDs using the large hole of HANARO is developed. It could be useful for the calibration experiment of the neutron detectors in the research reactors.

Self-Powered Neutron Detector Calibration Using a Large Vertical Irradiation Hole of HANARO

Science.gov (United States)

Kim, Myong-Seop; Park, Byung-Gun; Kang, Gi-Doo

2018-01-01

A calibration technology of the self-powered neutron detectors (SPNDs) using a large vertical irradiation hole of HANARO is developed. The 40 Rh-SPNDs are installed on the polycarbonate plastic support, and the gold wires with the same length as the effective length of the rhodium emitter of the SPND are also installed to measure the neutron flux on the SPND. They are irradiated at a low reactor power, and the SPND current is measured using the pico-ammeter. The external gamma-rays which affect the SPND current response are analyzed using the Monte Carlo simulation for various irradiation conditions in HANARO. It is confirmed that the effect of the external gamma-rays to the SPND current is dependent on the reactor characteristics, and that it is affected by materials around the detector. The current signals due to the external gamma-rays can be either positive or negative, in that the net flow of the current may be either in the same or the opposite direction as the neutron-induced current by the rhodium emitter. From the above procedure, the effective calibration methodology of multiple SPNDs using the large hole of HANARO is developed. It could be useful for the calibration experiment of the neutron detectors in the research reactors.

Developments, characterization and proton irradiation damage tests of AlN detectors for VUV solar observations

Energy Technology Data Exchange (ETDEWEB)

BenMoussa, A., E-mail: ali.benmoussa@stce.be [Solar Terrestrial Center of Excellence (STCE), Royal Observatory of Belgium, Circular Avenue 3, B-1180 Brussels (Belgium); Soltani, A.; Gerbedoen, J.-C [Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN), F-59652 Villeneuve d’Ascq (France); Saito, T. [Department of Environment and Energy, Tohoku Institute of Technology, 35-1, Yagiyama-Kasumi-cho, Taihaku-ku, Sendai, Miyagi 982-8577 (Japan); Averin, S. [Fryazino Branch of the Kotel’nikov Institute of Radioengineering and Electronics of Russian Academy of Sciences, 141190 Square Vvedenski 1, Fryazino, Moscow Region (Russian Federation); Gissot, S.; Giordanengo, B. [Solar Terrestrial Center of Excellence (STCE), Royal Observatory of Belgium, Circular Avenue 3, B-1180 Brussels (Belgium); Berger, G. [Catholic University of Louvain-la-Neuve, Chemin du Cyclotron 2, B-1348 Louvain la Neuve (Belgium); Kroth, U. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, D-10587 Berlin (Germany); De Jaeger, J.-C. [Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN), F-59652 Villeneuve d’Ascq (France); Gottwald, A. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, D-10587 Berlin (Germany)

2013-10-01

For next generation spaceborne solar ultraviolet radiometers, innovative metal–semiconductor–metal detectors based on wurtzite aluminum nitride are being developed and characterized. A set of measurement campaigns and proton irradiation damage tests was carried out to obtain their ultraviolet-to-visible characterization and degradation mechanisms. First results on large area prototypes up to 4.3 mm diameter are presented here. In the wavelength range of interest, this detector is reasonably sensitive and stable under brief irradiation with a negligible low dark current (3–6 pA/cm{sup 2}). No significant degradation of the detector performance was observed after exposure to protons of 14.4 MeV energy, showing a good radiation tolerance up to fluences of 1 × 10{sup 11} protons/cm{sup 2}.

3D detectors at ITC-irst: first irradiation studies

International Nuclear Information System (INIS)

Ronchin, S.; Boscardin, M.; Bosisio, L.; Cindro, V.; Dalla Betta, G.-F.; Piemonte, C.; Pozza, A.; Zoboli, A.; Zorzi, N.

2007-01-01

In the past two years, we have developed 3D detector technologies at ITC-irst (Trento, Italy). We have proposed a new 3D architecture, having columnar electrodes of one doping type only, allowing for a simplified fabrication process. In this paper, we report on preliminary results from the electrical characterization of devices irradiated with neutrons, showing that low depletion voltage values can be achieved even after very large fluences

Scanning of irradiated silicon detectors using $\\alpha$ particles and low energy protons

CERN Document Server

Casse, G L; Glaser, M; Kohout, Z; Konícek, J; Lemeilleur, F; Leroy, C; Linhart, V; Mares, J J; Pospísil, S; Roy, P; Sopko, B; Sinor, M; Svejda, J; Vorobel, V; Wilhelm, I

1999-01-01

In a spectroscopic study of non-irradiated and proton-irradiated silicon diodes, the detectors were illuminated from the front side and from the rear side by various alpha particle sources (mainly ThC') and by monoenergetic protons with energies from 1.0 to 2.5~MeV. Their response characteristics have been studied as a function of the incoming particle energy and the applied bias voltage. The charge collection efficiency was determined as a function of fluence

Neutron irradiation effects on silicon detectors structure, electrical and mechanical characteristics

International Nuclear Information System (INIS)

Rabinovich, E.; Golan, G.; Axelevich, A.; Inberg, A.; Oksman, M.; Rosenwaks, I.; Lubarsky, G.; Seidman, A.; Croitoru, N.; Rancoita, P.G.; Rattaggi, M.

1999-01-01

Neutron irradiation effects on (p-n) and Schottky-junction silicon detectors were studied. It was shown that neutron interactions with monocrystalline silicon create specific types of microstructure defects with morphology differing according to the level of neutron fluences (Φ). The isolated dislocation loops, formed by interstitial atoms were observed in microstructure images for 10 10 ≤ Φ ≤ 10 12 n/cm 2 . A strong change in the dislocation loops density and a cluster formation was observed for Φ ≥ 10 13 n/cm 2 . A drastic silicon damage was found for fluences over 10 14 n/cm 2 . These fluences created zones enriched with all types of dislocations, covering more than 50 % of the total surface area. A mechanical fragility appeared in that fluence range in a form of microcracks. 10 14 n/cm 2 appears to be a critical value of neutron irradiation because of the radiation damage described above and because the characteristics I f -V f of silicon detectors can be differentiated from those obtained at low fluences. (A.C.)

The results of the irradiations of microstrip detectors for the ATLAS tracker (SCT)

International Nuclear Information System (INIS)

Dervan, P.J.

2003-01-01

The SemiConductor Tracker (SCT) of ATLAS will operate in the Large Hadron Collider (LHC) at CERN, which will reach luminosities of 10 34 cm 2 s -1 . Silicon single-sided microstrip detectors will be used for particle tracking. Due to the proximity to the beam, the silicon detectors need to withstand damage from ionising radiation (10 Mrad total dose) and from non-ionising radiation such as neutrons (2x10 14 1 MeV equivalent neutrons/cm 2 total fluence). The final characteristics of the silicon SCT detectors which are needed to operate under LHC conditions and the conclusions reached after various years of test irradiation studies will be reported. The integration and performance of these detectors in complete SCT modules is also discussed

Study of the response of a silicon detector irradiated with 1 MeV neutrons; Etude de la reponse d`un detecteur Si irradie par des neutrons de 1 MeV

Energy Technology Data Exchange (ETDEWEB)

Roy, P [Montreal Univ., PQ (Canada). Lab. de Physique Nucleaire

1994-12-31

The author studied the response of an n-type silicon detector irradiated with 1 MeV neutrons at fluences ranging from 0.26x10{sup 13} to 11.19x10{sup 13} neutrons/cm{sup 2}. The response of the irradiated detector to {sup 241}Am alpha particles was measured. 13 refs., 7 figs.

The influence of fast neutron irradiation on the noise properties of silicon surface-barrier detectors

International Nuclear Information System (INIS)

Dabrowski, W.; Korbel, K.

1988-01-01

The susceptibility to the fast neutron irradiation of silicon surface-barrier detectors has been investigated. It was shown that the 1/f-noise decreases substantially with increasing fluence in the range from 10 10 n/cm 2 to 10 11 n/cm 2 . The deterioration of the detector performance is caused mainly by the positively-charged defects induced by the radiation. The critical value of the neutron fluence, at which the detector performance begins to be worsened was also determined. 5 refs., 5 figs. (author)

Characterization of 150 $\\mu$m thick epitaxial silicon detectors from different producers after proton irradiation

CERN Document Server

Hoedlmoser, H; Haerkoenen, J; Kronberger, M; Trummer, J; Rodeghiero, P

2007-01-01

Epitaxial (EPI) silicon has recently been investigated for the development of radiation tolerant detectors for future high-luminosity HEP experiments. A study of 150 mm thick EPI silicon diodes irradiated with 24GeV=c protons up to a fluence of 3 1015 p=cm2 has been performed by means of Charge Collection Efficiency (CCE) measurements, investigations with the Transient Current Technique (TCT) and standard CV=IV characterizations. The aim of the work was to investigate the impact of radiation damage as well as the influence of the wafer processing on the material performance by comparing diodes from different manufacturers. The changes of CCE, full depletion voltage and leakage current as a function of fluence are reported. While the generation of leakage current due to irradiation is similar in all investigated series of detectors, a difference in the effective doping concentration can be observed after irradiation. In the CCE measurements an anomalous drop in performance was found even for diodes exposed to ...

Characterization of hybrid self-powered neutron detector under neutron irradiation

CERN Document Server

Nakamichi, M; Yamamura, C; Nakazawa, M; Kawamura, H

2000-01-01

To evaluate the irradiation behaviour of a blanket mock-up on in-pile functional test, it is necessary to measure the neutron flux change in the in-pile mock-up by a neutron detector, such as the self-powered neutron detector (SPND). With its small-sized emitter, which has high sensitivity and fast response time, SPND is an indispensable tool in order to measure the local neutron flux change. In the case of an in-pile functional test, it is necessary that response time is less than 1s and ratio of SPND output current is more than 0.3 of output current of SPND with Rh emitter. Therefore, a hybrid SPND with high sensitivity and fast response time was developed. This hybrid SPND used a hybrid emitter, i.e. Co cladded Pt-13%Rh.

Thermal Module Tests with Irradiated 070 Detectors.

CERN Document Server

HOWCROFT, C L F

1998-01-01

Four n-in-n detectors were irradiated at KEK to a fluence of 3*1014 protons cm-2. These were used to construct a thermal barrel module to 070 drawings with an A3-90 baseboard at the Rutherford Appleton Laboratory. Thermal testes were conducted on the module, examining the runaway point and the temperatures across the silicon. The results obtained were used to calculate the runaway point under ATLAS conditions. It was concluded that this module meets the specifications in the Technical Design Report, of 160 mW mm-2@ 0°C for runaway and less than 5°C across the silicon. The module was also compared to a Finite Element Analysis, and showed a good agreement.

Self-Powered Neutron Detector Calibration Using a Large Vertical Irradiation Hole of HANARO

OpenAIRE

Kim Myong-Seop; Park Byung-Gun; Kang Gi-Doo

2018-01-01

A calibration technology of the self-powered neutron detectors (SPNDs) using a large vertical irradiation hole of HANARO is developed. The 40 Rh-SPNDs are installed on the polycarbonate plastic support, and the gold wires with the same length as the effective length of the rhodium emitter of the SPND are also installed to measure the neutron flux on the SPND. They are irradiated at a low reactor power, and the SPND current is measured using the pico-ammeter. The external gamma-rays which affe...

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.

Treatment verification and in vivo dosimetry for total body irradiation using thermoluminescent and semiconductor detectors

International Nuclear Information System (INIS)

Oliveira, F.F.; Amaral, L.L.; Costa, A.M.; Netto, T.G.

2014-01-01

The objective of this work is the characterization of thermoluminescent and semiconductor detectors and their applications in treatment verification and in vivo dosimetry for total body irradiation (TBI) technique. Dose measurements of TBI treatment simulation performed with thermoluminescent detectors inserted in the holes of a “Rando anthropomorphic phantom” showed agreement with the prescribed dose. For regions of the upper and lower chest where thermoluminescent detectors received higher doses it was recommended the use of compensating dose in clinic. The results of in vivo entrance dose measurements for three patients are presented. The maximum percentual deviation between the measurements and the prescribed dose was 3.6%, which is consistent with the action level recommended by the International Commission on Radiation Units and Measurements (ICRU), i.e., ±5%. The present work to test the applicability of a thermoluminescent dosimetric system and of a semiconductor dosimetric system for performing treatment verification and in vivo dose measurements in TBI techniques demonstrated the value of these methods and the applicability as a part of a quality assurance program in TBI treatments. - Highlights: • Characterization of a semiconductor dosimetric system. • Characterization of a thermoluminescent dosimetric system. • Application of the TLDs for treatment verification in total body irradiation treatments. • Application of semiconductor detectors for in vivo dosimetry in total body irradiation treatments. • Implementation of in vivo dosimetry as a part of a quality assurance program in radiotherapy

Modifications induced by gamma irradiation to Makrofol polymer nuclear track detector

Directory of Open Access Journals (Sweden)

A. Tayel

2015-03-01

Full Text Available The aim of the present study was extended from obtaining information about the interaction of gamma rays with Makrofol DE 7-2 track detector to introduce the basis that can be used in concerning simple sensor for gamma irradiation and bio-engineering applications. Makrofol polymer samples were irradiated with 1.25 MeV 60Co gamma radiations at doses ranging from 20 to 1000 kG y. The modifications of irradiated samples so induced were analyzed using UV–vis spectrometry, photoluminescence spectroscopy, and the measurements of Vickers’ hardness. Moreover, the change in wettability of irradiated Makrofol was investigated by the contact angle determination of the distilled water. UV–vis spectroscopy shows a noticeable decrease in the energy band gap due to gamma irradiation. This decrease could be attributed to the appearance of a shift to UV spectra toward higher wavelength region after irradiation. Photoluminescence spectra reveal a remarkable change in the integrated photoluminescence intensity with increasing gamma doses, which may be resulted from some matrix disorder through the creation of some defected states in the irradiated polymer. The hardness was found to increase from 4.78 MPa for the unirradiated sample to 23.67 MPa for the highest gamma dose. The contact angle investigations show that the wettability of the modified samples increases with increasing the gamma doses. The result obtained from present investigation furnishes evidence that the gamma irradiations are a successful technique to modify the Makrofol DE 7-2 polymer properties to use it in suitable applications.

Characterization of hybrid self-powered neutron detector under neutron irradiation

Energy Technology Data Exchange (ETDEWEB)

Nakamichi, M. E-mail: masaru@oarai.jaeri.go.jp; Nagao, Y.; Yamamura, C.; Nakazawa, M.; Kawamura, H

2000-11-01

To evaluate the irradiation behaviour of a blanket mock-up on in-pile functional test, it is necessary to measure the neutron flux change in the in-pile mock-up by a neutron detector, such as the self-powered neutron detector (SPND). With its small-sized emitter, which has high sensitivity and fast response time, SPND is an indispensable tool in order to measure the local neutron flux change. In the case of an in-pile functional test, it is necessary that response time is less than 1s and ratio of SPND output current is more than 0.3 of output current of SPND with Rh emitter. Therefore, a hybrid SPND with high sensitivity and fast response time was developed. This hybrid SPND used a hybrid emitter, i.e. Co cladded Pt-13%R000.

Is the Spencer-Attix cavity equation applicable for solid-state detectors irradiated in megavoltage electron beams?

International Nuclear Information System (INIS)

Mobit, P.N.; Sandison, G.A.; Calgary Univ., AB

2001-01-01

The applicability of the Spencer-Attix cavity equation in determining absorbed doses in water using solid state detectors irradiated by megavoltage electron beams have been examined. The calculations were performed using the EGSnrc Monte Carlo code. This work is an extension of a recently published article examining the perturbation of dose by solid state detectors in megavoltage electron beams. (orig.)

Planned studies of charge collection in non-uniformly irradiated Si and GaAs detectors

International Nuclear Information System (INIS)

Rosenfeld, A.; Reinhard, M.; Carolan, M.; Kaplan, G.; Lerch, M.; Alexiev, D.

1995-01-01

The aim of this project is to study the time and amplitude characteristics of silicon ion-implanted detectors non-uniformly irradiated with fast neutrons in order to predict their radiation behaviour in the LHC and space. It is expected in such detectors increases of the charge deficit due to trapping by large scale traps and transient time increases due to the reduction of the mobility. The theoretical model will be modified to describe the charge kinetics in the electrical field of the detector created by a non uniform space charge distribution. Experimental confirmation techniques are needed to develop non uniform predictable damage of silicon detectors using fast neutron sources (accelerators, reactors) and to study peculiarities of the charge transport in different parts of the detector. In parallel to experimental research will be started the theoretical development of the charge transport model for non-uniform distribution of space charge in the depletion layer (Neff). The model will include the linear distribution of Neff(y) along the detector as well as the change of sign of Neff (conversion from n to p type of silicon) inside the detector

Irradiation of 4H-SiC UV detectors with heavy ions

International Nuclear Information System (INIS)

Kalinina, E. V.; Lebedev, A. A.; Bogdanova, E.; Berenquier, B.; Ottaviani, L.; Violina, G. N.; Skuratov, V. A.

2015-01-01

Ultraviolet (UV) photodetectors based on Schottky barriers to 4H-SiC are formed on lightly doped n-type epitaxial layers grown by the chemical vapor deposition method on commercial substrates. The diode structures are irradiated at 25°C by 167-MeV Xe ions with a mass of 131 amu at a fluence of 6 × 10 9 cm −2 . Comparative studies of the optical and electrical properties of as-grown and irradiated structures with Schottky barriers are carried out in the temperature range 23–180°C. The specific features of changes in the photosensitivity and electrical characteristics of the detector structures are accounted for by the capture of photogenerated carriers into traps formed due to fluctuations of the conduction-band bottom and valence-band top, with subsequent thermal dissociation

Signal height in silicon pixel detectors irradiated with pions and protons

International Nuclear Information System (INIS)

Rohe, T.; Acosta, J.; Bean, A.; Dambach, S.; Erdmann, W.; Langenegger, U.; Martin, C.; Meier, B.; Radicci, V.; Sibille, J.; Trueb, P.

2010-01-01

Pixel detectors are used in the innermost part of multi-purpose experiments at the Large Hadron Collider (LHC) and are therefore exposed to the highest fluences of ionising radiation, which in this part of the detectors consists mainly of charged pions. The radiation hardness of the detectors has been tested thoroughly up to the fluences expected at the LHC. In case of an LHC upgrade the fluence will be much higher and it is not yet clear up to which radii the present pixel technology can be used. To establish such a limit, pixel sensors of the size of one CMS pixel readout chip (PSI46V2.1) have been bump bonded and irradiated with positive pions up to 6x10 14 n eq /cm 2 at PSI and with protons up to 5x10 15 n eq /cm 2 . The sensors were taken from production wafers of the CMS barrel pixel detector. They use n-type DOFZ material with a resistance of about 3.7kΩcm and an n-side read out. As the performance of silicon sensors is limited by trapping, the response to a Sr-90 source was investigated. The highly energetic beta-particles represent a good approximation to minimum ionising particles. The bias dependence of the signal for a wide range of fluences will be presented.

Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

Energy Technology Data Exchange (ETDEWEB)

Gallrapp, Christian

2015-07-01

The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ATLAS Pixel Detector as well as for applications in the ATLAS Experiment at HL-LHC conditions. The sensors considered in this work include various designs based on silicon and diamond as sensor material. The investigated designs include a planar silicon pixel design currently used in the ATLAS Experiment as well as a 3D pixel design which uses electrodes penetrating the entire sensor material. The diamond designs implement electrodes similar to the design used by the planar technology with diamond sensors made out of single- and poly-crystalline material. To investigate the sensor properties characterization tests are performed before and after irradiation with protons or neutrons. The measurements are used to determine the interaction between the read-out electronics and the sensors to ensure the signal transfer after irradiation. Further tests focus on the sensor performance itself which includes the analysis of the leakage current behavior and the charge

Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

International Nuclear Information System (INIS)

Gallrapp, Christian

2015-01-01

The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ATLAS Pixel Detector as well as for applications in the ATLAS Experiment at HL-LHC conditions. The sensors considered in this work include various designs based on silicon and diamond as sensor material. The investigated designs include a planar silicon pixel design currently used in the ATLAS Experiment as well as a 3D pixel design which uses electrodes penetrating the entire sensor material. The diamond designs implement electrodes similar to the design used by the planar technology with diamond sensors made out of single- and poly-crystalline material. To investigate the sensor properties characterization tests are performed before and after irradiation with protons or neutrons. The measurements are used to determine the interaction between the read-out electronics and the sensors to ensure the signal transfer after irradiation. Further tests focus on the sensor performance itself which includes the analysis of the leakage current behavior and the charge

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...

Charge collection efficiency recovery in heavily irradiated silicon detectors operated at cryogenic temperatures

CERN Document Server

Da Vià, C; Berglund, P; Borchi, E; Borer, K; Bruzzi, Mara; Buontempo, S; Casagrande, L; Chapuy, S; Cindro, V; Dimcovski, Zlatomir; D'Ambrosio, N; de Boer, Wim; Dezillie, B; Esposito, A P; Granat, V; Grigoriev, E; Heijne, Erik H M; Heising, S; Janos, S; Koivuniemi, J H; Konotov, I; Li, Z; Lourenço, C; Mikuz, M; Niinikoski, T O; Pagano, S; Palmieri, V G; Paul, S; Pirollo, S; Pretzl, Klaus P; Ropotar, I; Ruggiero, G; Salmi, J; Seppä, H; Suni, I; Smith, K; Sonderegger, P; Valtonen, M J; Zavrtanik, M

1998-01-01

The charge collection efficiency (CCE) of high resistivity silicon detectors, previously neutron irradiated up to 2*10/sup 15/ n/cm/sup 2/, was measured at different cryogenic temperatures and different bias voltages. In order to $9 study reverse annealing (RA) effects, a few samples were heated to 80 degrees C and kept at room temperature for several months after irradiation. For comparison other samples (NRA) where kept at -10 C after irradiation. The RA and $9 NRA samples, measured at 250 V forward and reverse bias voltage, present a common temperature threshold at 150 K. Below 120 K the CCE is constant and ranges between 55and 65 0.000000or the RA and NRA sample respectively. Similar CCE $9 was measured for a device processed with low resistivity contacts (OHMIC), opening the prospect for a consistent reduction of the cost of large area particle tracking. (7 refs).

Resistivity measurements on the neutron irradiated detector grade silicon materials

Energy Technology Data Exchange (ETDEWEB)

Li, Zheng

1993-11-01

Resistivity measurements under the condition of no or low electrical field (electrical neutral bulk or ENB condition) have been made on various device configurations on detector grade silicon materials after neutron irradiation. Results of the measurements have shown that the ENB resistivity increases with neutron fluence ({Phi}{sub n}) at low {phi}{sub n} (<10{sup 13} n/cm{sup 2}) and saturates at a value between 300 and 400 k{Omega}-cm at {phi}{sub n} {approximately}10{sup 13} n/cm{sup 2}. Meanwhile, the effective doping concentration N{sub eff} in the space charge region (SCR) obtained from the C-V measurements of fully depleted p{sup +}/n silicon junction detectors has been found to increase nearly linearly with {phi}{sub n} at high fluences ({phi}{sub n} > 10{sup 13} n/cm{sup 2}). The experimental results are explained by the deep levels crossing the Fermi level in the SCR and near perfect compensation in the ENB by all deep levels, resulting in N{sub eff} (SCR) {ne} n or p (free carrier concentrations in the ENB).

CR-39 as induced track detector in reactor: irradiation effect

International Nuclear Information System (INIS)

Zylberberg, H.

1989-07-01

A systematic study about reactor's neutrons radiation effect and gamma radiation effect on the properties of CR-39 that are significant for its use as induced fission track detector is showed. The following studies deserved attention: kinetics of the fission track chemical development; efficiency to register and to develop fission track; losses of developable tracks; variation in the number of developable tracks and variation in the visible and ultraviolet radiation spectrum. The dissertation is organized in seven specific chapters: solid state nuclear tracks (SSNT); CR-39 as SSNT; objectives and problems presentation; preparation and characterization of CR-39 as SSNT; gamma irradiation effect on the properties of CR-39 as SSNT; reactor neutron irradiation effect on the properties of CR-39 as SSNT and, results discussions and conclusions. The main work contributions are the use of CR-39 in the determination of fissionable nuclide as thorium and uranium in solid and liquid samples; gamma radiation damage on CR-39 as well as the reactor's neutron damage on CR-39. (B.C.A.) 62 refs, 53 figs, 21 tabs

ATLAS irradiation studies of n-in-n and p-in-n silicon microstrip detectors

CERN Document Server

Allport, P P; Buttar, C M; Carter, J; Drage, L M; Ferrère, D; Morgan, D; Riedler, P; Robinson, D

1999-01-01

Prior to the module production of the ATLAS silicon microstrip tracker for the barrel and the forward wheels, the characterisation of full-size prototype silicon detectors after radiation to fluences corresponding to 10 years of ATLAS operation is required. The behaviour of p-in-n and n-in-n detectors produced by several manufacturers before and after irradiation to a fluence of 3*10/sup 14/ protons/cm/sup 2/ at the CERN PS facility is discussed. This article summarises some recent results from the ATLAS SCT collaboration. The measurements of leakage current, full depletion voltage, signal-to-noise ratio and charge collection efficiency are presented. Despite the better efficiency performance of n-in-n detectors below depletion, the collaboration chose the p-in-n technology due to its simpler and less costly production since good charge collection efficiencies were achieved at the desired maximum bias voltage. (14 refs).

Measurements on irradiated L1 sensor prototypes for the D0 Run IIb silicon detector project

International Nuclear Information System (INIS)

Ahsan, M.; Bolton, T.; Carnes, K.; Demarteau, M.; Demina, R.; Gray, T.; Korjenevski, S.; Lehner, F.; Lipton, R.; Mao, H.S.; McCarthy, R.

2010-01-01

We report on irradiation studies of Hamamatsu prototype silicon microstrip detectors for layer 1 of the D0 upgrade project for Run IIb. The irradiation was carried out with 10 MeV protons up to proton fluence of 10 14 p/cm 2 at the J.R. Macdonald Laboratory, Manhatten, KS. The flux calibration was carefully checked using different dose normalization techniques. The results based on the obtained sensor leakage currents after irradiation show that the NIEL scaling hypothesis for low energy protons has to be applied with great care. We observe 30-40% less radiation damage in silicon for 10 MeV proton exposure than is expected from the predicted NIEL scaling.

Measurements on irradiated L1 sensor prototypes for the D0 Run IIb silicon detector project

Energy Technology Data Exchange (ETDEWEB)

Ahsan, M.; Bolton, T.; Carnes, K.; /Kansas State U.; Demarteau, M.; /Fermilab; Demina, R.; /Rochester U.; Gray, T.; /Kansas State U.; Korjenevski, S.; /Rochester U.; Lehner, F.; /Zurich U.; Lipton, R.; Mao, H.S.; /Fermilab; McCarthy, R.; /SUNY, Stony Brook /Kansas State U. /Fermilab

2010-01-01

We report on irradiation studies of Hamamatsu prototype silicon microstrip detectors for layer 1 of the D0 upgrade project for Run IIb. The irradiation was carried out with 10 MeV protons up to proton fluence of 10{sup 14} p/cm{sup 2} at the J.R. Macdonald Laboratory, Manhatten, KS. The flux calibration was carefully checked using different dose normalization techniques. The results based on the obtained sensor leakage currents after irradiation show that the NIEL scaling hypothesis for low energy protons has to be applied with great care. We observe 30-40% less radiation damage in silicon for 10 MeV proton exposure than is expected from the predicted NIEL scaling.

Irradiation induced effects in the FE-I4 front-end chip of the ATLAS IBL detector

CERN Document Server

La Rosa, Alessandro; The ATLAS collaboration

2016-01-01

The ATLAS Insertable B-Layer (IBL) detector was installed into the ATLAS experiment in 2014 and has been in operation since 2015. During the first year of IBL data taking an increase of the low voltage currents produced by the FE-I4 front-end chip was observed and this increase was traced back to the radiation damage in the chip. The dependence of the current on the total-ionising dose and temperature has been tested with Xray and proton irradiations and will be presented in this paper together with the detector operation guidelines.

Pre- and post-irradiation performance of FBK 3D silicon pixel detectors for CMS

International Nuclear Information System (INIS)

Krzywda, A.; Alagoz, E.; Bubna, M.; Obertino, M.; Solano, A.; Arndt, K.; Uplegger, L.; Betta, G.F. Dalla; Boscardin, M.; Ngadiuba, J.; Rivera, R.; Menasce, D.; Moroni, L.; Terzo, S.; Bortoletto, D.; Prosser, A.; Adreson, J.; Kwan, S.; Osipenkov, I.; Bolla, G.

2014-01-01

In preparation for the tenfold luminosity upgrade of the Large Hadron Collider (the HL-LHC) around 2020, three-dimensional (3D) silicon pixel sensors are being developed as a radiation-hard candidate to replace the planar ones currently being used in the CMS pixel detector. This study examines an early batch of FBK sensors (named ATLAS08) of three 3D pixel geometries: 1E, 2E, and 4E, which respectively contain one, two, and four readout electrodes for each pixel, passing completely through the bulk. We present electrical characteristics and beam test performance results for each detector before and after irradiation. The maximum fluence applied is 3.5×10 15 n eq /cm 2

Evaluation of formulation properties and skin penetration in the same additive-containing formulation

Directory of Open Access Journals (Sweden)

Yutaka Inoue

2014-01-01

Full Text Available The aim of this study is to examine the physicochemical properties of the external preparation, the effect on the skin permeability and the human senses. Miconazole nitrate cream formulation (MCZ-A: bland name and MCZ-B, −C, −D: generics to measure the physicochemical properties, was performed by the skin permeation test and human sensory test. The flattening, viscoelasticity, and water content of each cream were measured and each cream was subjected to near-infrared (NIR absorption spectroscopy and human sensory testing. The yield value was calculated based on measured flattening and was 734.8 dynes/cm2 for MCZ-A, 1198.9 dynes/cm2 for MCZ-B, 461.3 dynes/cm2 for MCZ-C and 3112.3 dynes/cm2 for MCZ-D. Measurement of viscoelasticity and viscosity revealed that MCZ-C had a smaller tanδ than the other 3 creams at 25 °C. NIR absorption spectroscopy revealed that MCZ-A had the highest absorption peak due to hydroxyl groups, followed by MCZ-C, −B, and then −D. Measurement of water content revealed that MCZ-A had a water content of 65.9%, MCZ-B, −C, and −D had a water content of around 56.3%. Human sensory testing revealed differences between MCZ-A and MCZ-C and between MCZ-B and MCZ-D in terms of spreadability and feel. These findings indicate that differences in water and oil content and emulsification resulted in the creams having different physical properties, such as flattening, internal structure, and dynamic viscoelasticity. NIR absorption spectroscopy, which allows non-destructive measurement of a sample’s physicochemical properties, and measurement of viscoelasticity and viscosity, which allows measurement of a sample’s dynamic viscoelasticity, revealed differences in the physical properties of creams. The skin permeation test, skin MCZ amount was 7.48 µg/cm2 for MCZ-A, 5.11 µg/cm2 for MCZ-B, 12.08 µg/cm2 for MCZ-C and 3.75 µg/cm2 for MCZ-D. In addition, since the drug spread is good about the skin migration

Performance of p-type micro-strip detectors after irradiation to $7.5x10^{15} p/cm^{2}$

CERN Document Server

Allport, Philip P; Lozano-Fantoba, Manuel; Sutcliffe, Peter; Velthuis, J J; Vossebeld, Joost Herman

2004-01-01

Exploiting the advantages of reading out segmented silicon from the n-side, we have produced test detectors with LHC pitch but 1 cm long strips which even after proton irradiation at the CERN PS to 7.5*10 /sup 15/ cm/sup -2/ show signal to noise greater than 8:1 using LHC speed electronics. This dose exceeds by a factor of 2 that required for a replacement of the ATLAS semiconductor tracker to cope with an upgrade of the LHC to a Super-LHC with 10 times greater luminosity. These detectors were processed on p-type starting material of resistivity ~ 2 k Omega cm and, unlike n-in-n designs, only required single-sided processing. Such technology should therefore provide a relatively inexpensive route to replacing the central tracking at both ATLAS and CMS for Super-LHC. The shorter strip length is required to limit the noise. Even at these extreme doses 30% of the non-irradiated signal is seen. This 7000e/sup -/ signal (in 280 mu m thick sensors) is very competitive with the post irradiation performance of other,...

The effects of intense gamma-irradiation on the alpha-particle response of silicon carbide semiconductor radiation detectors

International Nuclear Information System (INIS)

Ruddy, Frank H.; Seidel, John G.

2007-01-01

Silicon Carbide (SiC) semiconductor radiation detectors are being developed for alpha-particle, X-ray and Gamma-ray, and fast-neutron energy spectrometry. SiC detectors have been operated at temperatures up to 306 deg. C and have also been found to be highly resistant to the radiation effects of fast-neutron and charged-particle bombardments. In the present work, the alpha-particle response of a SiC detector based on a Schottky diode design has been carefully monitored as a function of 137 Cs gamma-ray exposure. The changes in response have been found to be negligible for gamma exposures up to and including 5.4 MGy, and irradiations to higher doses are in progress

High-rate irradiation of 15 mm muon drift tubes and development of an ATLAS compatible readout driver for micromegas detectors

Energy Technology Data Exchange (ETDEWEB)

Zibell, Andre

2014-06-06

The upcoming luminosity upgrades of the LHC accelerator at CERN demand several upgrades to the detectors of the ATLAS muon spectrometer, mainly due to the proportionally increasing rate of uncorrelated background irradiation. This concerns also the ''Small Wheel'' tracking stations of the ATLAS muon spectrometer, where precise muon track reconstruction will no longer be assured when around 2020 the LHC luminosity is expected to reach values 2 to 5 times the design luminosity of 1 x 10{sup 34} cm{sup -2}s{sup -1}, and when background hit rates will exceed 10 kHz/cm{sup 2}. This, together with the need of an additional triggering station in this area with an angular resolution of 1 mrad, requires the construction of ''New Small Wheel'' detectors for a complete replacement during the long maintenance period in 2018 and 2019. As possible technology for these New Small Wheels, high-rate capable sMDT drift tubes have been investigated, based on the ATLAS 30 mm Monitored Drift Tube technology, but with a smaller diameter of 15 mm. In this work, a prototype sMDT chamber has been tested under the influence of high-rate irradiation with protons, neutrons and photons at the Munich tandem accelerator, simulating the conditions within a high luminosity LHC experiment. Tracking resolution and detection efficiency for minimum ionizing muons are presented as a function of irradiation rate. The experimental muon trigger geometry allows to distinguish between efficiency degradation due to deadtime effects and space charge in the detectors. Using modified readout electronics the analog pulse shape of the detector has been investigated for gain reduction and potential irregularities due to the high irradiation rates and ionization doses. This study shows that the sMDT detectors would fulfill all requirements for successful use in the ATLAS New Small Wheel endcap detector array, with an average spatial resolution of 140 μm and a track

High-rate irradiation of 15 mm muon drift tubes and development of an ATLAS compatible readout driver for micromegas detectors

International Nuclear Information System (INIS)

Zibell, Andre

2014-01-01

The upcoming luminosity upgrades of the LHC accelerator at CERN demand several upgrades to the detectors of the ATLAS muon spectrometer, mainly due to the proportionally increasing rate of uncorrelated background irradiation. This concerns also the ''Small Wheel'' tracking stations of the ATLAS muon spectrometer, where precise muon track reconstruction will no longer be assured when around 2020 the LHC luminosity is expected to reach values 2 to 5 times the design luminosity of 1 x 10 34 cm -2 s -1 , and when background hit rates will exceed 10 kHz/cm 2 . This, together with the need of an additional triggering station in this area with an angular resolution of 1 mrad, requires the construction of ''New Small Wheel'' detectors for a complete replacement during the long maintenance period in 2018 and 2019. As possible technology for these New Small Wheels, high-rate capable sMDT drift tubes have been investigated, based on the ATLAS 30 mm Monitored Drift Tube technology, but with a smaller diameter of 15 mm. In this work, a prototype sMDT chamber has been tested under the influence of high-rate irradiation with protons, neutrons and photons at the Munich tandem accelerator, simulating the conditions within a high luminosity LHC experiment. Tracking resolution and detection efficiency for minimum ionizing muons are presented as a function of irradiation rate. The experimental muon trigger geometry allows to distinguish between efficiency degradation due to deadtime effects and space charge in the detectors. Using modified readout electronics the analog pulse shape of the detector has been investigated for gain reduction and potential irregularities due to the high irradiation rates and ionization doses. This study shows that the sMDT detectors would fulfill all requirements for successful use in the ATLAS New Small Wheel endcap detector array, with an average spatial resolution of 140 μm and a track reconstruction efficiency

Characterization of 150μm thick epitaxial silicon detectors from different producers after proton irradiation

International Nuclear Information System (INIS)

Hoedlmoser, H.; Moll, M.; Haerkoenen, J.; Kronberger, M.; Trummer, J.; Rodeghiero, P.

2007-01-01

Epitaxial (EPI) silicon has recently been investigated for the development of radiation tolerant detectors for future high-luminosity HEP experiments. A study of 150μm thick EPI silicon diodes irradiated with 24GeV/c protons up to a fluence of 3x10 15 p/cm 2 has been performed by means of Charge Collection Efficiency (CCE) measurements, investigations with the Transient Current Technique (TCT) and standard CV/IV characterizations. The aim of the work was to investigate the impact of radiation damage as well as the influence of the wafer processing on the material performance by comparing diodes from different manufacturers. The changes of CCE, full depletion voltage and leakage current as a function of fluence are reported. While the generation of leakage current due to irradiation is similar in all investigated series of detectors, a difference in the effective doping concentration can be observed after irradiation. In the CCE measurements an anomalous drop in performance was found even for diodes exposed to very low fluences (5x10 13 p/cm 2 ) in all measured series. This result was confirmed for one series of diodes in TCT measurements with an infrared laser. TCT measurements with a red laser showed no type inversion up to fluences of 3x10 15 p/cm 2 for n-type devices whereas p-type diodes undergo type inversion from p- to n-type for fluences higher than ∼2x10 14 p/cm 2

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.

Study of intense pulse irradiation effects on silicon targets considered as ground matter for optical detectors

International Nuclear Information System (INIS)

Muller, O.

1994-12-01

This study aim was centered on morphological and structural alterations induced by laser irradiation on silicon targets considered as ground matter for optical detectors. First we recalled the main high light intensity effects on the condensed matter. Then we presented the experimental aspects. The experimental studies were achieved on two sample types: SiO 2 /Si and Si. Two topics were studied: the defect chronology according to wavelength and pulse length, and the crystalline quality as well as the structure defects of irradiated zones by Raman spectroscopy. Finally, irradiation of Si targets by intense pulsed beams may lead to material fusion. This phenomenon is particularly easy when the material is absorbent, when the pulse is short and when the material is superficially oxidized. (MML). 204 refs., 93 figs., 21 tabs., 1 appendix

Gamma irradiation effects on the thermal, optical and structural properties of Cr-39 nuclear track detector

International Nuclear Information System (INIS)

Nouh, S.A.; Said, A.F.; Atta, M.R.; EL-Mellegy, W.M.; EL-Meniawi, S.

2006-01-01

A study of the effect of gamma irradiation on the thermal, optical and structural properties of CR-39 diglycol carbonate solid state nuclear track detector (SSNTD) has been carried out. Samples from CR-39 polymer were irradiated with gamma doses at levels between 20 and 300 KGy. Non-isothermal studies were carried out using thermo-gravimetry (TG), differential thermo-gravimetry (DTG) and differential thermal analysis (DTA) to obtain the activation energy of decomposition and the transition temperatures for the non-irradiated and irradiated CR-39 samples. In addition, optical and structural property studies were performed on non-irradiated and irradiated CR-39 samples using refractive index and X-ray diffraction measurements. The variation of onset temperature of decomposition (To) thermal activation energy of decomposition (Ea) melting temperature (Tm) refractive index (n) and the mass fraction of the amorphous phase with the gamma dose were studied. It was found that many changes in the thermal, optical and structural properties of the CR-39 polymer could be produced by gamma irradiation via the degradation and cross linking mechanisms. Also, the gamma dose gave an advantage for increasing the correlation between the thermal stability of CR-39 polymer and the bond formation created by the ionizing effect of gamma radiation

An X-Ray facility to perform irradiation tests and TID studies on electronics and detectors

CERN Document Server

Brundu, Davide; Cadeddu, Sandro; Wyllie, Ken; Ciambrone, Paolo

2018-01-01

The X-Ray irradiation system of the LHCb group, installed in Cagliari, is presented; with a particular focus on the setup configuration and dose rate calibration. The system can be used to perform Total Ionizing Dose (TID) studies for detectors, readout and front-end electronics. It was already used to test the nSYNC chip, an ASIC for the readout of the LHCb upgraded muon system.

Lorentz angle measurements in irradiated silicon detectors between 77 K and 300 K

International Nuclear Information System (INIS)

Bartsch, V.; Boer, W. de; Bol, J.

2001-01-01

Future experiments are using silicon detectors in a high radiation environment and in high magnetic fields. The radiation tolerance of silicon improves by cooling it to temperatures below 180 K. However, at low temperatures the mobility increases, which leads to larger deflections of the charge carriers by the Lorentz force. We present measurements of the Lorentz angle between 77 K and 300 K before and after irradiation with a primary beam of 21 MeV protons to a flux of 10 13 /cm 2 . (author)

GIF++: A new CERN Irradiation Facility to test large-area particle detectors for the High-Luminosity LHC program

CERN Document Server

Guida, Roberto

2016-01-01

The high-luminosity LHC (HL-LHC) upgrade is setting a new challenge for particle detector technologies. The increase in luminosity will produce a higher particle background with respect to present conditions. To study performance and stability of detectors at LHC and future HL-LHC upgrades, a new dedicated facility has been built at CERN: the new Gamma Irradiation Facility (GIF++). The GIF++ is a unique place where high energy charged particle beams (mainly muons) are combined with gammas from a 14 TBq 137Cesium source which simulates the background radiation expected at the LHC experiments. Several centralized services and infrastructures are made available to the LHC detector community to facilitate the different R&D; programs.

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)

Cryogenic Tracking Detectors

CERN Multimedia

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

2002-01-01

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

The signal shape from the LHCb vertex locator prototype detectors

International Nuclear Information System (INIS)

Charles, M.

2003-01-01

Measurements of the SCT128A ASIC pulse shape, when reading out non-irradiated and irradiated prototype detectors for the LHCb VELO, are presented. The detectors studied were two n-on-n prototype detectors fabricated by Hamamatsu, and a p-on-n prototype detector fabricated by MICRON

First charge collection and position-precision data on the medium-resistivity silicon strip detectors before and after neutron irradiation up to 2x1014 n/cm2

International Nuclear Information System (INIS)

Li Zheng; Dezillie, B.; Eremin, V.; Li, C.J.; Verbitskaya, E.

1999-01-01

Test strip detectors of 125 μm, 500 μm, and 1 mm pitches with about 1 cm 2 areas have been made on medium-resistivity silicon wafers (1.3 and 2.7 kΩ cm). Detectors of 500 μm pitch have been tested for charge collection and position precision before and after neutron irradiation (up to 2x10 14 n/cm 2 ) using 820 and 1030 nm laser lights with different beam-spot sizes. It has been found that for a bias of 250 V a strip detector made of 1.3 kΩ cm (300 μm thick) can be fully depleted before and after an irradiation of 2x10 14 n/cm 2 . For a 500 μm pitch strip detector made of 2.7 kΩ cm tested with an 1030 nm laser light with 200 μm spot size, the position reconstruction error is about 14 μm before irradiation, and 17 μm after about 1.7x10 13 n/cm 2 irradiation. We demonstrated in this work that medium resistivity silicon strip detectors can work just as well as the traditional high-resistivity ones, but with higher radiation tolerance. We also tested charge sharing and position reconstruction using a 1030 nm wavelength (300 μm absorption length in Si at RT) laser, which provides a simulation of MIP particles in high-physics experiments in terms of charge collection and position reconstruction

TSC measurements on proton-irradiated p-type Si-sensors

Energy Technology Data Exchange (ETDEWEB)

Donegani, Elena; Fretwurst, Eckhart; Garutti, Erika; Junkes, Alexandra [University of Hamburg (Germany)

2016-07-01

Thin n{sup +}p Si sensors are potential candidates for coping with neutron equivalent fluences up to 2.10{sup 16} n{sub eq}/cm{sup 2} and an ionizing dose in the order of a few MGy, which are expected e.g. for the HL-LHC upgrade. The aim of the present work is to provide experimental data on radiation-induced defects in order to: firstly, get a deeper understanding of the properties of hadron induced defects, and secondly develop a radiation damage model based on microscopic measurements. Therefore, the outcomes of Thermally Stimulated Current measurements on 200 μm thick Float-Zone (FZ) and Magnetic Czochralski (MCz) diodes will be shown, as a results of irradiation with 23 MeV protons and isothermal annealing. The samples were irradiated in the fluence range (0.3-1).10{sup 14} n{sub eq}/cm{sup 2}, so that the maximal temperature at which the TSC signal is still sharply distinguishable from the dark current is 200 K. In particular, special focus will be given to the defect introduction rate and to the issue of boron removal in p-type silicon. Annealing studies allow to distinguish which defects mainly contribute to the leakage current and which to the space charge, and thus correlate microscopic defects properties with macroscopic sensor properties.

Effect of neutron irradiation on etching, optical and structural properties of microscopic glass slide used as a solid state nuclear track detector

International Nuclear Information System (INIS)

Singh, Surinder; Kaur Sandhu, Amanpreet; Prasher, Sangeeta; Prakash Pandey, Om

2007-01-01

Microscopic glass slides are soda-lime glasses which are readily available and are easy to manufacture with low production cost. The application of these glasses as nuclear track detector will help us to make use of these glasses as solid-state nuclear track detector. The present paper describes the variation in the etching, optical and structural properties of the soda-lime microscopic glass slides due to neutron irradiation of different fluences. The color transformation and an increase in the optical absorption with neutron irradiation are observed. Both the bulk and track etch rates are found to increase with neutron fluence, thus showing a similar dependence on neutron fluence, but the sensitivity remains almost constant

Charge collection and space charge distribution in neutron-irradiated epitaxial silicon detectors

International Nuclear Information System (INIS)

Poehlsen, Thomas

2010-04-01

In this work epitaxial n-type silicon diodes with a thickness of 100 μm and 150 μm are investigated. After neutron irradiation with fluences between 10 14 cm -2 and 4 x 10 15 cm -2 annealing studies were performed. CV-IV curves were taken and the depletion voltage was determined for different annealing times. All investigated diodes with neutron fluences greater than 2 x 10 14 cm -2 showed type inversion due to irradiation. Measurements with the transient current technique (TCT) using a pulsed laser were performed to investigate charge collection effects for temperatures of -40 C, -10 C and 20 C. The charge correction method was used to determine the effective trapping time τ eff . Inconsistencies of the results could be explained by assuming field dependent trapping times. A simulation of charge collection could be used to determine the field dependent trapping time τ eff (E) and the space charge distribution in the detector bulk. Assuming a linear field dependence of the trapping times and a linear space charge distribution the data could be described. Indications of charge multiplication were seen in the irradiated 100 μm thick diodes for all investigated fluences at voltages above 800 V. The space charge distribution extracted from TCT measurements was compared to the results of the CV measurements and showed good agreement. (orig.)

Detector on wheel system (flying spot)

International Nuclear Information System (INIS)

Annis, M.

1980-01-01

An arc-shaped x-ray beam penetrates an arcual cross-sectional area of a body and the attentuated transmitted beam irradiates a portion of a circular array of detectors on a rotating disc. The detectors operate to generate signals proportional to the intensity of the incident transmitted radiation. The beam and detectors are moved along the axis of the body during rotation of the disc to irradiate adjacent cross-sectional areas of the body. A computer operated crt receives the detector signals and displays an image of the radiation attentuation characteristics of the scanned arcual areas

Transmutation detectors

Energy Technology Data Exchange (ETDEWEB)

Viererbl, L., E-mail: vie@ujv.c [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Lahodova, Z. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Klupak, V. [Nuclear Research Institute Rez plc (Czech Republic); Sus, F. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Kucera, J. [Research Centre Rez Ltd. (Czech Republic); Nuclear Physics Institute, Academy of Sciences of the Czech Republic (Czech Republic); Kus, P.; Marek, M. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic)

2011-03-11

We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

Transmutation detectors

International Nuclear Information System (INIS)

Viererbl, L.; Lahodova, Z.; Klupak, V.; Sus, F.; Kucera, J.; Kus, P.; Marek, M.

2011-01-01

We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

Trapping induced Neff and electrical field transformation at different temperatures in neutron irradiated high resistivity silicon detectors

International Nuclear Information System (INIS)

Eremin, V.; Li, Z.; Iljashenko, I.

1994-02-01

The trapping of both non-equilibrium electrons and holes by neutron induced deep levels in high resistivity silicon planar detectors have been observed. In the experiments Transient Current and Charge Techniques, with short laser light pulse excitation have been applied at temperature ranges of 77--300 k. Light pulse illumination of the front (p + ) and back (n + ) contacts of the detectors showed effective trapping and detrapping, especially for electrons. At temperatures lower than 150 k, the detrapping becomes non-efficient, and the additional negative charge of trapped electrons in the space charge region (SCR) of the detectors leads to dramatic transformations of the electric field due to the distortion of the effective space charge concentration N eff . The current and charge pulses transformation data can be explained in terms of extraction of electric field to the central part of the detector from the regions near both contacts. The initial field distribution may be recovered immediately by dropping reverse bias, which injects both electrons and holes into the space charge region. In the paper, the degree of the N eff distortions among various detectors irradiated by different neutron fluences are compared

CdTe/CZT under high flux irradiation

International Nuclear Information System (INIS)

Strassburg, Matthias; Schroeter, Christian; Hackenschmied, Peter

2011-01-01

Direct converting quantum counting detectors based on cadmium telluride and cadmium zinc telluride have been investigated with respect to their properties under intense X-ray irradiation. To derive a detailed picture of the performance of such detectors, the influence of the electric field, the detector thickness, the temperature and the intensity of the X-ray irradiation was studied. The results are discussed in terms of the ''polarization'' phenomenon, a reduction of the electric field strength inside the detector due to immobile charge carriers accumulating during irradiation. Furthermore, the impact of Te-inclusions and -precipitates is presented.

Studies of frequency dependent C-V characteristics of neutron irradiated p+-n silicon detectors

International Nuclear Information System (INIS)

Li, Zheng; Kraner, H.W.

1990-10-01

Frequency-dependent capacitance-voltage fluence (C-V) characteristics of neutron irradiated high resistivity silicon p + -n detectors have been observed up to a fluence of 8.0 x 10 12 n/cm 2 . It has been found that frequency dependence of the deviation of the C-V characteristic (from its normal V -1/2 dependence), is strongly dependent on the ratio of the defect density and the effective doping density N t /N' d . As the defect density approaches the effective dopant density, or N t /N' d → 1, the junction capacitance eventually assumes the value of the detector geometry capacitance at high frequencies (f ≤ 10 5 Hz), independent of voltage. A two-trap-level model using the concept of quasi-fermi levels has been developed, which predicts both the effects of C-V frequency dependence and dopant compensation observed in this study

Time development and flux dependence of neutron-irradiation induced defects in silicon pad detectors

CERN Document Server

Zontar, D; Kramberger, G; Mikuz, M

1999-01-01

1x1 cm sup 2 silicon pad p sup + -n-n sup + detectors were irradiated with fast neutrons from the TRIGA research reactor in Ljubljana to fluences from 5x10 sup 1 sup 3 to 10 sup 1 sup 4 n/cm sup 2. The observed time development of annealing of the full-depletion voltage (FDV) could be fitted by a constant and two exponentials. The characteristic time of the fast component is 4 h, independent of temperature in the interval 0-15 deg. C. A comparison of MESA and planar pad detectors shows a 20-30% lower FDV for the MESA. A search for a flux dependence of the radiation damage was performed in the range from 2x10 sup 8 to 5x10 sup 1 sup 5 n/cm sup 2 s and no systematic differences were observed.

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...

Charge collection efficiency and resolution of an irradiated double-sided silicon microstrip detector operated at cryogenic temperatures

International Nuclear Information System (INIS)

Borer, K.; Janos, S.; Palmieri, V.G.; Buytaert, J.; Chabaud, V.; Chochula, P.; Collins, P.; Dijkstra, H.; Niinikoski, T.O.; Lourenco, C.; Parkes, C.; Saladino, S.; Ruf, T.; Granata, V.; Pagano, S.; Vitobello, F.; Bell, W.; Bartalini, P.; Dormond, O.; Frei, R.; Casagrande, L.; Bowcock, T.; Barnett, I.B.M.; Da Via, C.; Konorov, I.; Paul, S.; Schmitt, L.; Ruggiero, G.; Stavitski, I.; Esposito, A.

2000-01-01

This paper presents results on the measurement of the cluster shapes, resolution and charge collection efficiency of a double-sided silicon microstrip detector after irradiation with 24 GeV protons to a fluence of 3.5x10 14 p/cm 2 and operated at cryogenic temperatures. An empirical model is presented which describes the expected cluster shapes as a function of depletion depth, and is shown to agree with the data. It is observed that the clusters on the p-side broaden if the detector is under-depleted, leading to a degradation of resolution and efficiency. The model is used to make predictions for detector types envisaged for the LHC experiments. The results also show that at cryogenic temperature the charge collection efficiency varies depending on the operating conditions of the detector and can reach values of 100% at unexpectedly low bias voltage. By analysing the cluster shapes it is shown that these variations are due to changes in depletion depth. This phenomenon, known as the 'Lazarus effect', can be related to similar recent observations on diode behaviour

Irradiation effects in fused quartz 'Suprasil' as a detector of fission fragments under high flux of reactor neutrons

International Nuclear Information System (INIS)

Moraes, O.M.G. de.

1984-01-01

A systematic study about the registration characteristics of synthetic fused quartz 'Suprasil I' use as a detector of fission fragments under high flux of reactor neutrons and the effects of irradiation on it was performed. Fission fragments of 252 Cf, gamma radiation doses of of 60 Co up to 150 MGy, and integrated neutrons fluxes up to 10 20 n/cm 2 were used. A model to explain the effects on track registration and development characteristics of 'Suprasil I' irradiated on reactors were proposed, based on the obtained results for efficiency an for annealing. (C.G.C.) [pt

Effect of radiation on the electrical properties of plastic detector CR-39

International Nuclear Information System (INIS)

Mahmoud, S.A.; Hamed, A.E.; Abou El-Kier, A.A.; Mousse, M.G.; Kassem, M.E.; El-Shafey, E.M.

1994-01-01

The effect of high alpha-particle fluence on plastic detector CR-39 was studied by measuring the electrical properties of the detector as a function of irradiation dose and frequency using an impedance meter in the frequency range 0.005-500 kHz. When the plastic detector CR-39 is exposed to high irradiation doses, it loses its advantage as a track detector, because of the overlapping of the tracks occurring in the detector at high irradiation fluence. Through the present measurements of dielectric permittivity and conductivity at different frequencies and temperatures, CR-39 could be used as a dosimeter for high irradiation doses

Effect of radiation on the electrical properties of plastic detector CR-39

Energy Technology Data Exchange (ETDEWEB)

Mahmoud, S.A.; Hamed, A.E.; Abou El-Kier, A.A.; Mousse, M.G.; Kassem, M.E.; El-Shafey, E.M. (Physics Department Faculty of Science, Alexandria University, Alexandria (Egypt))

1994-10-15

The effect of high alpha-particle fluence on plastic detector CR-39 was studied by measuring the electrical properties of the detector as a function of irradiation dose and frequency using an impedance meter in the frequency range 0.005-500 kHz. When the plastic detector CR-39 is exposed to high irradiation doses, it loses its advantage as a track detector, because of the overlapping of the tracks occurring in the detector at high irradiation fluence. Through the present measurements of dielectric permittivity and conductivity at different frequencies and temperatures, CR-39 could be used as a dosimeter for high irradiation doses.

Charge collection and space charge distribution in neutron-irradiated epitaxial silicon detectors

Energy Technology Data Exchange (ETDEWEB)

Poehlsen, Thomas

2010-04-15

In this work epitaxial n-type silicon diodes with a thickness of 100 {mu}m and 150 {mu}m are investigated. After neutron irradiation with fluences between 10{sup 14} cm{sup -2} and 4 x 10{sup 15} cm{sup -2} annealing studies were performed. CV-IV curves were taken and the depletion voltage was determined for different annealing times. All investigated diodes with neutron fluences greater than 2 x 10{sup 14} cm{sup -2} showed type inversion due to irradiation. Measurements with the transient current technique (TCT) using a pulsed laser were performed to investigate charge collection effects for temperatures of -40 C, -10 C and 20 C. The charge correction method was used to determine the effective trapping time {tau}{sub eff}. Inconsistencies of the results could be explained by assuming field dependent trapping times. A simulation of charge collection could be used to determine the field dependent trapping time {tau}{sub eff}(E) and the space charge distribution in the detector bulk. Assuming a linear field dependence of the trapping times and a linear space charge distribution the data could be described. Indications of charge multiplication were seen in the irradiated 100 {mu}m thick diodes for all investigated fluences at voltages above 800 V. The space charge distribution extracted from TCT measurements was compared to the results of the CV measurements and showed good agreement. (orig.)

The origin of double peak electric field distribution in heavily irradiated silicon detectors

CERN Document Server

Eremin, V; Li, Z

2002-01-01

The first observation of double peak (DP) electric field distribution in heavily neutron irradiated (>10 sup 1 sup 4 n/cm sup 2) semiconductor detectors has been published about 6 yr ago. However, this effect was not quantitatively analyzed up to now. The explanation of the DP electric field distribution presented in this paper is based on the properties of radiation induced deep levels in silicon, which act as deep traps, and on the distribution of the thermally generated free carrier concentration in the detector bulk. In the frame of this model, the earlier published considerations on the so-called 'double junction (DJ) effect' are discussed as well. The comparison of the calculated electric field profiles at different temperatures with the experimental ones allows one to determine a set of deep levels. This set of deep levels, and their charge filling status are essential to the value and the distribution of space charge in the space charge region in the range of 305-240 K, which is actual temperature ran...

First charge collection and position-precision data on the medium-resistivity silicon strip detectors before and after neutron irradiation up to 2x10 sup 1 sup 4 n/cm sup 2

CERN Document Server

Li Zheng; Eremin, V; Li, C J; Verbitskaya, E

1999-01-01

Test strip detectors of 125 mu m, 500 mu m, and 1 mm pitches with about 1 cm sup 2 areas have been made on medium-resistivity silicon wafers (1.3 and 2.7 k OMEGA cm). Detectors of 500 mu m pitch have been tested for charge collection and position precision before and after neutron irradiation (up to 2x10 sup 1 sup 4 n/cm sup 2) using 820 and 1030 nm laser lights with different beam-spot sizes. It has been found that for a bias of 250 V a strip detector made of 1.3 k OMEGA cm (300 mu m thick) can be fully depleted before and after an irradiation of 2x10 sup 1 sup 4 n/cm sup 2. For a 500 mu m pitch strip detector made of 2.7 k OMEGA cm tested with an 1030 nm laser light with 200 mu m spot size, the position reconstruction error is about 14 mu m before irradiation, and 17 mu m after about 1.7x10 sup 1 sup 3 n/cm sup 2 irradiation. We demonstrated in this work that medium resistivity silicon strip detectors can work just as well as the traditional high-resistivity ones, but with higher radiation tolerance. We als...

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...

Study of gamma irradiation effects on the etching and optical properties of CR-39 solid state nuclear track detector and its application to uranium assay in soil samples

International Nuclear Information System (INIS)

Amol Mhatre; Kalsi, P.C.

2011-01-01

The gamma irradiation effects in the dose range of 2.5-43.0 Mrad on the etching and optical characteristics of CR-39 solid state nuclear track detector (SSNTD) have been studied by using etching and UV-Visible spectroscopic techniques. From the measured bulk etch rates at different temperatures, the activation energies for bulk etching at different doses have also been determined. It is seen that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. The optical band gaps of the unirradiated and the gamma -irradiated detectors determined from the UV-Visible spectra were found to decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation. The present studies can be used for the estimation of gamma dose in the range of 2.5-43.0 Mrad and can also be used for estimating track registration efficiency in the presence of gamma dose. The CR-39 detector has also been applied for the assay of uranium in some soil samples of Jammu city. (author)

Radiation tolerance of oxygenated n-strip read-out detectors

CERN Document Server

Allport, P P; Greenall, A

2003-01-01

Following earlier work on 'oxygenated' detectors in terms of charge collection efficiencies after proton irradiation, full-size detectors for the LHC have been processed with n-side read-out on oxygen enhanced n-type silicon substrates. Two hundred-micron-thick detectors have been inhomogeneously irradiated up to doses of 7 multiplied by 10**1**4p/cm**2 using 24 GeV protons from the CERN PS. Results are presented on the charge collection efficiencies as a function of operating voltage for regions of the detectors irradiated to different doses, using LHC speed analogue read-out electronics. The measurements confirm the expectations which led to our original proposal of such detectors which are now being envisaged for the silicon-based detector systems at the LHC designed to withstand the greatest doses. The possibilities for survival at an upgraded luminosity LHC (Super-LHC) are also briefly discussed.

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.).

Noise behaviour of semiinsulating GaAs particle detectors at various temperatures before and after irradiation

International Nuclear Information System (INIS)

Tenbusch, F.; Braunschweig, W.; Chu, Z.; Krais, R.; Kubicki, T.; Luebelsmeyer, K.; Pandoulas, D.; Rente, C.; Syben, O.; Toporowski, M.; Wittmer, B.; Xiao, W.J.

1998-01-01

We investigated the noise behaviour of surface barrier detectors (double sided Schottky contact) made of semiinsulating GaAs. Two types of measurements were performed: equivalent noise charge (ENC) and noise power density spectra in a frequency range from 10 Hz to 500 kHz. The shape of the density spectra are a powerful tool to examine the physical origin of the noise, before irradiation it is dominated by generation-recombination processes caused by deep levels. Temperature dependent noise measurements reveal the deep level parameters like activation energy and cross section, which are also extracted by analyzing the time transients of the charge pulse from α-particles. After irradiation with protons, neutrons and pions the influence of the deep levels being originally responsible for the noise is found to decrease and a reduction of the noise over the entire frequency range with increasing fluence is observed. (orig.)

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.)

Multicomponent activation detector measurements of reactor neutron spectra

International Nuclear Information System (INIS)

Sandberg, J.; Aarnio, P. A.; Routti, J. T.

1984-01-01

Information on the neutron flux is required in many applications of research reactors, such as activation analysis or radiation damage measurements. Flux spectrum measurements are commonly carried out with activation foils. The reaction types used are threshold reactions in the fast energy region, resonance reactions in the intermediate region and neutron capture reactions with l/v-cross section in the thermal region. It has been shown that it is possible to combine several detector elements into homogeneous multicomponent detectors. The activities of all detector reaction products can be determined with a single gamma spectrum measurement. The multicomponent principle sets some restrictions on the choice of detector reactions, for example, each product nuclide may be produced in one reaction only. Separate multicomponent threshold and resonance detectors were designed for the fast and intermediate regions, respectively. The detectors were fabricated in polyethylene irradiation capsules or quartz glass ampoules, and they were irradiated in a cadmium cover. The detectors were succesfully used in the irradiation ring and in the core of a Triga reactor. The intermediate and fast neutron spectrum was unfolded with the least-squares unfolding program LOUHI. According to the preliminary results multicomponent activation detectors might constitute a convenient means for carrying out routine neutron spectrum measurements in research reactors. (orig.)

Study etching characteristics of a track detector CR-39 with ultraviolet laser irradiation

International Nuclear Information System (INIS)

Dwaikat, Nidal; Iida, Toshiyuki; Sato, Fuminobu; Kato, Yushi; Ishikawa, Ippei; Kada, Wataru; Kishi, Atsuya; Sakai, Makoto; Ihara, Yohei

2007-01-01

The effect of pulsed ultraviolet Indium-doped Yttrium Aluminum Garnet (UV-In:YAG) laser of λ=266 nm, pulse energy 42 mJ/pulse at repetition rate10 Hz on the etching characteristics of Japanese CR-39 was studied at various energy intensities. Fifteen detectors were divided into two sets, each of seven samples and one sample was kept as a reference.The first set (post-exposed) was first exposed to alpha radiation with close contact to 241 Am and then treated in air with laser in the energy intensity range from 40 to160 J/cm 2 , 20 J/cm 2 in step. The second set (pre-exposed) was irradiated in reverse process (laser+alpha) with the same sources as the first set and under the same condition. The laser energy intensities ranged between 20 and 140 J/cm 2 , 20 J/cm 2 in step. For post-exposed samples (alpha+laser) bulk etch rate decreases up to 60 J/cm 2 and increases thereafter, while for pre-exposed samples (laser+alpha) the bulk etch rate oscillates without showing any precise periodicity. The bulk etch rate for both sets was found to be the same at 60≤energy intensity≤80 J/cm 2 and this may indicate that the same structural changes have happened. The track etch rate was found to be equal to the bulk etch rate for both sets, so the sensitivity is constant. In both sets several changes on the detector surfaces: tracks of different sizes and shapes and high density within the laser spot were observed. Out of the laser spot, the tracks become larger and lower density, indicating cross-linking and scission have happened, simultaneously, on the same surface as a result of UV-laser irradiation

Diamond Detector Technology: Status and Perspectives

CERN Document Server

Reichmann, M; Artuso, M; Bachmair, F; Bäni, L; Bartosik, M; Beacham, J; Beck, H; Bellini, V; Belyaev, V; Bentele, B; Berdermann, E; Bergonzo, P; Bes, A; Brom, J-M; Bruzzi, M; Cerv, M; Chiodini, G; Chren, D; Cindro, V; Claus, G; Collot, J; Cumalat, J; Dabrowski, A; D'Alessandro, R; Dauvergne, D; de Boer, W; Dorfer, C; Dünser, M; Eremin, V; Eusebi, R; Forcolin, G; Forneris, J; Frais-Kölbl, H; Gallin-Martel, L; Gallin-Martel, M L; Gan, K K; Gastal, M; Giroletti, C; Goffe, M; Goldstein, J; Golubev, A; Gorišek, A; Grigoriev, E; Grosse-Knetter, J; Grummer, A; Gui, B; Guthoff, M; Haughton, I; Hiti, B; Hits, D; Hoeferkamp, M; Hofmann, T; Hosslet, J; Hostachy, J-Y; Hügging, F; Hutton, C; Jansen, H; Janssen, J; Kagan, H; Kanxheri, K; Kasieczka, G; Kass, R; Kassel, F; Kis, M; Konovalov, V; Kramberger, G; Kuleshov, S; Lacoste, A; Lagomarsino, S; Lo Giudice, A; Lukosi, E; Maazouzi, C; Mandic, I; Mathieu, C; Menichelli, M; Mikuž, M; Morozzi, A; Moss, J; Mountain, R; Murphy, S; Muškinja, M; Oh, A; Oliviero, P; Passeri, D; Pernegger, H; Perrino, R; Picollo, F; Pomorski, M; Potenza, R; Quadt, A; Re, A; Riley, G; Roe, S; Sanz-Becerra, D A; Scaringella, M; Schaefer, D; Schmidt, C J; Schnetzer, S; Sciortino, S; Scorzoni, A; Seidel, S; Servoli, L; Smith, S; Sopko, B; Sopko, V; Spagnolo, S; Spanier, S; Stenson, K; Stone, R; Sutera, C; Tannenwald, B; Taylor, A; Traeger, M; Tromson, D; Trischuk, W; Tuve, C; Uplegger, L; Velthuis, J; Venturi, N; Vittone, E; Wagner, S; Wallny, R; Wang, J C; Weingarten, J; Weiss, C; Wengler, T; Wermes, N; Yamouni, M; Zavrtanik, M

2018-01-01

The planned upgrade of the LHC to the High-Luminosity-LHC will push the luminosity limits above the original design values. Since the current detectors will not be able to cope with this environment ATLAS and CMS are doing research to find more radiation tolerant technologies for their innermost tracking layers. Chemical Vapour Deposition (CVD) diamond is an excellent candidate for this purpose. Detectors out of this material are already established in the highest irradiation regimes for the beam condition monitors at LHC. The RD42 collaboration is leading an effort to use CVD diamonds also as sensor material for the future tracking detectors. The signal behaviour of highly irradiated diamonds is presented as well as the recent study of the signal dependence on incident particle flux. There is also a recent development towards 3D detectors and especially 3D detectors with a pixel readout based on diamond sensors.

Design Study and Optimization of Irradiation Facilities for Detector and Accelerator Equipment Testing in the SPS North Area at CERN

CERN Document Server

AUTHOR|(CDS)2079748; Stekl, Ivan

Due to increasing performance of LHC during the last years, the strong need of new detector and electronic equipment test areas at CERN appeared from user communities. This thesis reports on two test facilities: GIF++ and H4IRRAD. GIF++, an upgrade of GIF facility, is a combined high-intensity gamma and particle beam irradiation facility for testing detectors for LHC. It combines a high-rate 137Cs source, providing photons with energy of 662 keV, together with the high-energy secondary particle beam from SPS. H4IRRAD is a new mixed-field irradiation area, designed for testing LHC electronic equipment for radiation damage effects. In particular, large volume assemblies such as full electronic racks of high current power converters can be tested. The area uses alternatively an attenuated primary 400 GeV/c proton beam from SPS, or a secondary, mainly proton, beam of 280 GeV/c directed towards a copper target. Different shielding layers are used to reproduce a radiation field similar to the LHC “tunnel” and �...

Aging measurements on triple-GEM detectors operated with $CF_{4}$- based gas mixtures

CERN Document Server

Alfonsi, M; Bencivenni, G; Bonivento, W; Cardini, A; Lener, M P; Murtas, F; Pinci, D; Raspino, D; Saitta, B; De Simone, P

2004-01-01

We present the results of a global irradiation test of full size triple-GEM detectors operated with CF/sub 4/-based gas mixtures. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV gamma from a /sup 60/Co source. After the irradiation test the detectors performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in the GEM detector during the strong irradiation.

Measurements of Silicon Detector Thermal Runaway

CERN Document Server

Heusch, C A; Moser, H G

1999-01-01

We measured thermal runaway properties of previously irradiated silicon detectors cooled by TPG bars. We simulated their expected behaviour to measure the energy gap in the detector material and to test the validity of various underlying assumptions.

Temperature detectors on irradiated silicon base

International Nuclear Information System (INIS)

Karimov, M.; Dzhalelov, M.A.; Kurbanov, A.O.

2005-01-01

It is well known, that the most suitable for thermal resistors production is compensated silicon with impurities forming deep lying in forbidden zone, having big negative resistance temperature coefficients (RTC). In the capacity of initial materials for thermal resistors with negative RTC the n-type monocrystalline silicon with specific resistance ∼30 Ω·cm at 300 K is applied. Before the irradiation the phosphorus diffusion is realizing at temperature ∼1000 deg. C for 10 min. Irradiation is putting into practise by WWR-SM reactor fast neutrons within the range (7-10)·10 13 cm -2 . The produced resistors have nominal resistance range (8-20)·10 3 Ω·cm, coefficient of the thermal sensitivity B=4000-6000 deg. C., RTC α 300K =4-6.6 %/grad. It is shown, that offered method allows to obtain same type resistors characteristics on the base of neutron-irradiated material

Study of natural diamond detector spectrometric properties under neutron irradiation

CERN Document Server

Alekseyev, A B; Kaschuck, Y; Krasilnikov, A; Portnov, D; Tugarinov, S

2002-01-01

Natural diamond detector (NDD) performance was studied up to a neutron fluence of 10 sup 1 sup 5 neutron/cm sup 2. The variations of the NDD spectrometric response to incident alpha-particles from sup 2 sup 4 sup 1 Am source after exposure to fast neutron fluences up to 3x10 sup 1 sup 6 n/cm sup 2 were examined. No significant variations up to the level of 10 sup 1 sup 4 n/cm sup 2 were observed. Degradation of charge collection efficiency at higher fluences is reported. No remarkable increase of the NDD leakage current and count rate change had been observed up to a neutron fluence of 3x10 sup 1 sup 6 n/cm sup 2. The charge collection efficiency variations of neutron irradiated diamond spectrometer were studied ex situ under gamma-rays, beta-radiation and visible light excitation. Charge collection efficiency restoration up to 75% level and the NDD performance stabilization by extrinsic low-intensity visible light (550 nm

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

Heavy ion measurement by chemical detectors

International Nuclear Information System (INIS)

Huebner, K.; Erzgraeber, G.; Eichhorn, K.

1979-02-01

In testing the applicability of the threshold system polyvinyl alcohol/methyl orange/chloral hydrate/sodium tetraborate to the quantitative detection of single particles, the chemical detector was irradiated with 4 He, 12 C, 18 O, 22 He ions of different LET. Detectors with 4 different borax concentrations (chloral hydrate concentration kept constant) have been irradiated. The dose causing the colour change increased linearly with the borax concentration. For equal borax concentrations this dose increases with increasing LET due to the decreasing G value of the HCl. The fluence ranges measurable with the various detector compositions are given. 4 He and 18 O ion ranges have been determined. The measured depth dose curves have been corrected because the dose is LET-dependent. The experimentally determined ranges are in good agreement with values calculated for the detector material

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

The two sides of silicon detectors

International Nuclear Information System (INIS)

Devine, S.R.

2001-10-01

Results are presented on in situ irradiation of silicon detector's at cryogenic temperature. The results show that irradiation at cryogenic temperatures does not detrimentally effect a silicon detectors performance when compared to its irradiation at room temperature. Operation of silicon devices at cryogenic temperatures offers the advantage of reducing radiation-induced leakage current to levels of a few pA, while at 130K the Lazarus Effect plays an important role i.e. minimum voltage required for full depletion. Performing voltage scans on a 'standard' silicon pad detector pre- and post annealing, the charge collection efficiency was found to be 60% at 200V and 95% at 200V respectively. Time dependence measurements are presented, showing that for a dose of 6.5x10 14 p/cm 2 (450GeV protons) the time dependence of the charge collection efficiency is negligible. However, for higher doses, 1.2x10 15 p/cm 2 , the charge collection efficiency drops from an initial measured value of 67% to a stable value of 58% over a period of 15 minutes for reversed biased diodes. An analysis of the 'double junction' effect is also presented. A comparison between the Transient Current Technique and an X-ray technique is presented. The double junction has been observed in p + /n/n + silicon detectors after irradiation beyond 'type inversion', corresponding to a fluence equivalent to ∼3x10 13 cm -2 1MeV neutrons, producing p + /p/n + and essentially two p-n junctions within one device. With increasing bias voltage, as the electric field is extending into the detector bulk from opposite sides of the silicon detector, there are two distinct depletion regions that collect charge signal independently. Summing the signal charge from the two regions, one is able to reconstruct the initial energy of the incident particle. From Transient Current measurements it is apparent that E-field manipulation is possible by excess carrier injection, enabling a high enough E-field to extend across the

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.

Aging measurements on triple-GEM detectors operated with $CF_{4}$-based gas mixtures

CERN Document Server

Alfonsi, M; De Simone, P; Murtas, F; Poli Lener, M P; Bonivento, W; Cardini, A; Raspino, D; Saitta, B; Pinci, D; Baccaro, S; 10.1016/j.nuclphysbps.2005.03.054

2006-01-01

We present the results of a global irradiation test of full size triple-GEM detectors operated with CF/sub 4/-based gas mixtures. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV detectors performances have been measured with X-rays and with a 3 Ge V pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in a GEM detector during a strong irradiation.

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

Development of silicon detectors for Beam Loss Monitoring at HL-LHC

Science.gov (United States)

Verbitskaya, E.; Eremin, V.; Zabrodskii, A.; Bogdanov, A.; Shepelev, A.; Dehning, B.; Bartosik, M. R.; Alexopoulos, A.; Glaser, M.; Ravotti, F.; Sapinski, M.; Härkönen, J.; Egorov, N.; Galkin, A.

2017-03-01

Silicon detectors were proposed as novel Beam Loss Monitors (BLM) for the control of the radiation environment in the vicinity of the superconductive magnets of the High-Luminosity Large Hadron Collider. The present work is aimed at enhancing the BLM sensitivity and therefore the capability of triggering the beam abort system before a critical radiation load hits the superconductive coils. We report here the results of three in situ irradiation tests of Si detectors carried out at the CERN PS at 1.9-4.2 K. The main experimental result is that all silicon detectors survived irradiation up to 1.22× 1016 p/cm2. The third test, focused on the detailed characterization of the detectors with standard (300 μm) and reduced (100 μm) thicknesses, showed only a marginal difference in the sensitivity of thinned detectors in the entire fluence range and a smaller rate of signal degradation that promotes their use as BLMs. The irradiation campaigns produced new information on radiation damage and carrier transport in Si detectors irradiated at the temperatures of 1.9-4.2 K. The results were encouraging and permitted to initiate the production of the first BLM prototype modules which were installed at the end of the vessel containing the superconductive coil of a LHC magnet immersed in superfluid helium to be able to test the silicon detectors in real operational conditions.

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

Performance studies under high irradiation and ageing properties of resistive bulk Micromegas chambers at the new CERN Gamma Irradiation Facility

International Nuclear Information System (INIS)

Sidiropoulou, O.; Gonzalez, B. Alvarez; Bianco, M.; Farina, E.M.; Iengo, P.; Longo, L.; Pfeiffer, D.; Wotschack, J.

2017-01-01

Resistive bulk Micromegas chambers, produced at CERN, have been installed at the new CERN Gamma Irradiation Facility (GIF++) in order to study the effects of ageing and to evaluate the detector behaviour under high irradiation. The chambers have an active area of 10×10 cm 2 , strip pitch of 400 μm and an amplification gap of 128 μm. We present the detector performance as a function of the background rate of up to 20 MHz/cm 2 . - Highlights: • Small-size resistive bulk Micromegas detectors have been exposed to the new GIF++. • 9 months irradiation to γ up to 20 Mhz/cm 2 . 0.09 C/cm 2 collected integrated charge. • Νo degradation of the detector performance was observed. • Muon tracks successfully reconstructed up to 68 kHz/cm 2 gamma background. • Higher background rates will be studied in the coming months.

Comparison of relevant parameters of multi-pixel sensors for tracker detectors after irradiation with high proton and neutron fluences

International Nuclear Information System (INIS)

Bergholz, Matthias

2016-03-01

The further increase of the luminosity of the Large Hadron Collider (LHC) at CERN requires new sensors for the tracking detector of the Compact Muon Soleniod (CMS) experiment. These sensors must be more radiation hard and of a finer granularity to lower the occupancy. In addition the new sensor modules must have a lower material budget and have to be self triggering. Sensor prototypes, the so called ''MPix''-sensors, produced on different materials were investigated for their radiation hardness. These sensors were fully characterized before and after irradiation. Of particular interest was the comparison of different bias methods, different materials and the influence of various geometries. The degeneration rate differs for the different sensor materials. The increase of the dark current of Float-Zone-Silicon is stronger for thicker sensors and less than for Magnetic-Czochralski-Silicon sensors. Both tested bias structures are damaged by the irradiation. The poly silicon resistance increases after irradiation by fifty percent. The Punch-Through-Structure is more effected by irradiation. The punch-through voltage increase by a factor of two. Due to the higher pixel current, the working point of the sensor is shifted to smaller differential resistances.

Investigation of the charge collection for strongly irradiated silicon strip detectors of the CMS ECAL Preshower

International Nuclear Information System (INIS)

Bloch, Ph.; Peisert, A.; Chang, Y.H.; Chen, A.E.; Hou, S.; Lin, W.T.; Cheremukhin, A.E.; Golutvin, I.A.; Urkinbaev, A.R.; Zamyatin, N.I.; Loukas, D.

2001-01-01

Strongly irradiated (2.3·10 14 n/cm 2 ) silicon strip detectors of different size, thickness and different design options were tested in a muon beam at CERN in 1999. A charge collection efficiency in excess of 85% and a signal-to-noise ratio of about 6 are obtained in all cases at high enough bias voltage. Details of the charge collection in the interstrip and the guard ring region and cross-talk between strips were also studied. We find that the charge collection efficiency and the cross-talk between strips depend on the interstrip distance

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

Response of cellulose nitrate track detectors to electron doses

CERN Document Server

Segovia, N; Moreno, A; Vazquez-Polo, G; Santamaría, T; Aranda, P; Hernández, A

1999-01-01

In order to study alternative dose determination methods, the bulk etching velocity and the latent track annealing of LR 115 track detectors was studied during electron irradiation runs from a Pelletron accelerator. For this purpose alpha irradiated and blank detectors were exposed to increasing electron doses from 10.5 to 317.5 kGy. After the irradiation with electrons the detectors were etched under routine conditions, except for the etching time, that was varied for each electron dose in order to reach a fixed residual thickness. The variation of the bulk etching velocity as a function of each one of the electron doses supplied, was interpolated in order to obtain dosimetric response curves. The observed annealing effect on the latent tracks is discussed as a function of the total electron doses supplied and the temperature.

The Impact of Different Control Techniques of Industrial Irradiation Processing Units (Cobalt 60 Irradiator) on Maintaining Safety for Radiation and Environment

International Nuclear Information System (INIS)

Keshek, A. B.

2010-01-01

Negative results were caused by fire events inside and outside the industrial irradiation facilities by Co 60 irradiators. It included bad effects on equipment cables, electrical components, product boxes, products, fire detectors radiation detectors various radiation concrete shielding and big volumes of smoke. Big volumes of water and water spray were used to resist and to cool fire inside irradiation facilities. Flooded water was collected on the floor of the irradiation room, it tranced through maze legs to outside the main door and through the electrical tunnels casing big damage outside irradiation unit. The work show two different designs, the first system is the cleaner agent fire suppression by carbon dioxide. CO 2 containers are located outside irradiation concrete facility, and attached by special metallic pipes system. By fire detector and automatic control valves maintain CO 2 to suppress fire inside irradiation room and maintain clean agent fire suppression. The second system depend on Nuclear Regulatory commission C.F.R 10 of 2005 to prevent flooding and trance. The need to design a new system which trances the excessive water from inside irradiation room and to prevent it from escaping to outside irradiation facility during resisting fire by water curtion the excessive water is escaped from the storage pool by electrical pump; the second line will trance the excessive water outside the main building to store inside separated tank

Heavy ion measurements by use of chemical detectors

International Nuclear Information System (INIS)

Huebner, K.; Erzgraeber, G.; Eichhorn, K.

1980-01-01

In order to test whether the threshold system polyvinyl alcohol/methyl organe/chloral hydrate/sodium tetraborate permits quantitative detection of individual particles, the chemical detector was irradiated at the JINR U-200 cyclotron with 4 He, 12 C, 18 O, 22 Ne ions having different LET. Irradiations were performed with detectors of four different borax concentrations (the chloral hydrate concentration being constant). The colour change dose Dsub(u) increases linearly with increasing borax concentration and at constant borax concentration with increasing LET. Hence it follows that the G value of dehydrochlorination decreases with increasing LET. Fluence ranges measurable with detectors of different composition are given for the heavy ions studied. (author)

Investigation of the effectiveness of standard materials used to the performance evaluation of the PSL detectors for irradiated foods

International Nuclear Information System (INIS)

Sekiguchi, Masayuki; Nakagawa, Seiko; Goto, Michiko; Yamazaki, Masao

2009-01-01

Six different minerals (dolomite, bentonite, montmorillonite, kaolin, talc, activated clay), gloss sheets for laser(LP) and ink-Jet printer(IP), and four types of glass fiber filters (GA-100, GB-100R, GD-120, GF/C) have been investigated for availability as the standard material for maintenance and calibration of photostimulated luminescence (PSL) detectors for irradiated foods. Montmorillonite applied to a paper disc had an adequate PSL intensity caused by natural radiation in comparison with other minerals, but the stability of the PSL was affected by light exposure in the manufacturing process. The PSL intensity of IP was drastically decreased one day after irradiation but LP had an adequate PSL intensity with the exception of high level background counts just after irradiation. The glass fiber filters, except for GF/C, differed little in PSL intensities between the upper and under side, but compression in the filter caused fluctuation in the PSL intensity. Changes in PSL intensities of LP and GA-100 with time differences after irradiation were further studied. The cumulate photon counts were markedly decreased in the first two months for GA-100, and in the first month for LP after irradiation. GA-100 showed relatively less variation in cumulate photon counts compared with LP and the paprika standard in a series of studies. (author)

Degradation of charge sharing after neutron irradiation in strip silicon detectors with different geometries

International Nuclear Information System (INIS)

Casse, G.; Dervan, P.; Forshaw, D.; Greenall, A.; Huse, T.; Tsurin, I.; Wormald, M.

2013-01-01

The aim of the CERN/RD50 collaboration is the improvement of the radiation tolerance of semiconductor detectors for future experiments at high-luminosity colliders. In the RD50 framework, evidence of enhanced signal charge in severely irradiated silicon detectors (diodes, segmented planar and 3D devices) was found. The underlying mechanism was labelled charge multiplication. This has been one of the most exciting results from the research activity of RD50 because it could allow for a greatly extended radiation tolerance, if the mechanism is to be found controllable and tuneable. The charge multiplication mechanism is governed by impact ionisation from electrons drifting in high electric field. The electric field profile is influenced by the geometry of the implanted electrodes. In order to investigate the influence of the diode implantation geometry on charge multiplication, the RD50 collaboration has commissioned the production of miniature microstrip silicon sensors with various choices of strip pitch and strip width over pitch (w/p) ratios. Moreover, some of the sensors were produced interleaving readout strips with dummy intermediate ones in order to modify the electric field profile. These geometrical solutions can influence both charge multiplication and charge sharing between adjacent strips. The initial results of this study are here presented

Alpha-particle radiobiological experiments using thin CR-39 detectors

International Nuclear Information System (INIS)

Chan, K. F.; Siu, S. Y. M.; McClella, K. E.; Tse, A. K. W.; Lau, B. M. F.; Nikezic, D.; Richardson, B. J.; Lam, P. K. S.; Fong, W. F.; Yu, K. N.

2006-01-01

The present paper studied the feasibility of applying comet assay to evaluate the DNA damage in individual HeLa cervix cancer cells after alpha-particle irradiation. We prepared thin CR-39 detectors (<20 μm) as cell-culture substrates, with UV irradiation to shorten the track formation time. After irradiation of the HeLa cells by alpha particles, the tracks on the underside of the CR-39 detector were developed by chemical etching in (while floating on) a 14 N KOH solution at 37 deg. C. Comet assay was then applied. Diffusion of DNA out of the cells could be generally observed from the images of stained DNA. The alpha-particle tracks corresponding to the comets developed on the underside of the CR-39 detectors could also be observed by just changing the focal plane of the confocal microscope. (authors)

Self-powered in-core detectors of cobalt type

International Nuclear Information System (INIS)

Jonsson, Georg

1975-01-01

Testing and development of self-powered neutron detectors with a cobalt emitter is described. Long term irradiation at 400 deg C is expected to indicate insulation quality, change in calibration and 60 Co build-up. Dynamic tests to investigate possible transient effects due to temperature changes are being performed on a number of detectors up to about 600 deg C. A long term irradiation at low temperature has been terminated after 4.5 years. On completion, neutron dose was estimated to be 5.6 x 10 21 nvt and the 60 Co background was 9.3 % of the full flux signal. A recently introduced long term test is expected to provide data on instability effects due to 61 Co. For a BWR in-core detector installation, the main advantage of cobalt detectors, apart from the small size, appears to be long life. Development work is being done on detectors with vanadium-cobalt emitters, electronic separation of fast and delayed signals and reduction of gamma sensitivity. (O.T.)

Alanine Radiation Detectors in Therapeutic Carbon Ion Beams

DEFF Research Database (Denmark)

Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo

of the depth dose curves. Solid state detectors, such as diamond detectors, radiochromic films, TLDs and the amino acid alanine are used due to there good spatial resolution. If used in particle beams their response often exhibits a dependence on particle energy and type, so the acquired signal is not always...... proportional to absorbed dose. A model by Hansen and Olsen, based on the Track Structure Theory is available, which can predict the relative efficiency of some detectors, when the particle spectrum is known. For alanine detectors the model was successfully validated by Hansen and Olsen for several ion species...... at energies below 20 MeV/u. We implemented this model in the Monte Carlo code FLUKA. At the GSI heavy ion facility in Darmstadt, Germany, alanine has been irradiated with carbon ions at energies between 88 an 400 MeV/u, which is the energy range used for therapy. The irradiation and the detector response have...

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.

Radiation studies on resistive bulk-micromegas chambers at the CERN Gamma Irradiation Facility

CERN Document Server

Alvarez Gonzalez, Barbara; Camerlingo, Maria Teresa; Farina, Edoardo; Iengo, Paolo; Longo, Luigi; Samarati, Jerome; Sidiropoulou, Ourania; Wotschack, Joerg

2018-01-01

With the growing diffusion of resistive Micromegas detectors in HEP experiments the study of long-term aging behaviour is becoming more and more relevant. Two resistive bulk-Micromegas detectors were installed in May 2015 at the CERN Gamma Irradiation Facility and exposed to an intense gamma irradiation with the aim to study the detector behavior under high irradiation and the long-term aging. The detectors have an active area of 10 × 10 cm 2 , readout strip pitch of 400 μ m , amplification gap of 128 μ m and drift gap of 5 mm. The desired accumulated charge of more than 0.2 C/cm 2 has been reached for both chambers, equivalent to 10 years of HL-LHC operation. The efficiency, amplification, and resolution of the Micromegas after this long-term irradiation period is compared with the performance of a non irradiated detector. In addition, the latest results of the measured particle rate as a function of the amplification voltage is presented and compared with those obtained in 2015.

Radiation Damage Effects and Performance of Silicon Strip Detectors using LHC Readout Electronics

CERN Document Server

AUTHOR|(CDS)2067734

1998-01-01

Future high energy physics experiments as the ATLAS experiment at CERN, will use silicon strip detectors for fast and high precision tracking information. The high hadron fluences in these experiments cause permanent damage in the silicon.Additional energy levels are introduced in the bandgap thus changing the electrical properties such as leakage current and full depletion voltage V_fd .Very high leakage currents are observed after irradiation and lead to higher electronic noise and thus decrease the spatial resolution.V_fd increases to a few hundred volts after irradiation and eventually beyond the point of stable operating voltages. Prototype detectors with either p-implanted strips (p-in-n) and n-implanted strip detectors (n-in-n) were irradiated to the maximum expected fluence in ATLAS.The irradiation and the following study of the current and V_fd were carried out under ATLAS operational conditions.The evolution of V_fd after irradiation is compared to models based on diode irradiations.The qualitative ...

Recent progress in low-temperature silicon detectors

International Nuclear Information System (INIS)

Abreu, M.; D'Ambrosio, N.; Bell, W.; Berglund, P.; Borchi, E.; Boer, W. de; Borer, K.; Bruzzi, M.; Buontempo, S.; Casagrande, L.; Chapuy, S.; Cindro, V.; Devine, S.R.H.; Dezillie, B.; Dierlamm, A.; Dimcovski, Z.; Eremin, V.; Esposito, A.; Granata, V.; Grigoriev, E.; Grohmann, S.; Hauler, F.; Heijne, E.; Heising, S.; Hempel, O.; Herzog, R.; Haerkoenen, J.; Janos, S.; Jungermann, L.; Konorov, I.; Li, Z.; Lourenco, C.; De Masi, R.; Menichelli, D.; Mikuz, M.; Niinikoski, T.O.; O'Shea, V.; Pagano, S.; Palmieri, V.G.; Paul, S.; Pretzl, K.; Smith, K.; Solano, B. Pere; Sousa, P.; Pirollo, S.; Rato Mendes, P.; Ruggiero, G.; Sonderegger, P.; Tuominen, E.; Verbitskaya, E.; Da Via, C.; Watts, S.; Wobst, E.; Zavrtanik, M.

2003-01-01

The CERN RD39 Collaboration studies the possibility to extend the detector lifetime in a hostile radiation environment by operating them at low temperatures. The outstanding illustration is the Lazarus effect, which showed a broad operational temperature range around 130 K for neutron irradiated silicon detectors

Performance of irradiated CVD diamond micro-strip sensors

International Nuclear Information System (INIS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.; Plano, R.; Somalwar, S.V.; Thomson, G.B.

2002-01-01

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article, we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a β-source and the performance before and after intense (>10 15 /cm 2 ) proton- and pion-irradiations. We find that low dose irradiation increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiation with protons 2.2x10 15 p/cm 2 lowers the signal-to-noise ratio slightly. Intense irradiation with pions 2.9x10 15 π/cm 2 lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations

Performance of irradiated CVD diamond micro-strip sensors

Science.gov (United States)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L. S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J. L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R. J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.; Plano, R.; Somalwar, S. V.; Thomson, G. B.

2002-01-01

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article, we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a β-source and the performance before and after intense (>10 15/cm 2) proton- and pion-irradiations. We find that low dose irradiation increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiation with protons 2.2×10 15 p/ cm2 lowers the signal-to-noise ratio slightly. Intense irradiation with pions 2.9×10 15 π/ cm2 lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations.

Development of cryogenic tracking detectors for very high luminosity experiments

CERN Document Server

Härkönen, J; Anbinderis, T; Bates, R; de Boer, W; Borchi, E; Bruzzi, M; Buttar, C; Chen, W; Cindro, V; Czellar, S; Eremin, V; Furgeri, A; Gaubas, E; Heijne, E; Ilyashenko, I; Kalesinskas, V; Krause, M; Li, Z; Luukka, P; Mandic, I; Menichelli, D; Mikuz, M; Militaru, O; Mueller, S; Niinikoski, T O; O’Shea, V; Parkes, C; Piotrzkowski, K; Pirollo, S; Pusa, P; Räisänen, J; Rouby, X; Tuominen, E; Tuovinen, E; Vaitkus, J; Verbitskaya, E; Väyrynen, S; Zavrtanik, M

2009-01-01

Experimental results and simulations of Charge Collection Efficiency (CCE) of Current Injected Detectors (CIDs) are focused. CID is a concept where the current is limited by the space charge. The injected carriers will be trapped by the deep levels. This induces a stable electric field through the entire bulk regardless of the irradiation fluence the detector has been exposed. Our results show that the CCE of CIDs is about two times higher than of regular detectors when irradiated up to 1×1016 cm−2. The higher CCE is achieved already at −50 °C temperatures.

Heavy-ion irradiation effects on passivated implanted planar silicon detectors

International Nuclear Information System (INIS)

Coster, W. de; Brijs, B.; Vandervorst, W.; Burger, P.

1992-01-01

Commercially available p + nn + passivated implanted planar silicon detectors have been shown to be very performing for standard RBS-analysis with 4 He beams. Lifetimes are found to range up till >10 9 particles. The end of lifetime occurs concurrent with internal breakdown of the detector. Inverted n + np + detectors where the junction is located well outside the damage region, are expected to be less sensitive to the radiation damage and to have a higher lifetime. In the present paper the characteristics for heavy-ion detection of both types of detector are investigated and discussed upon. (orig.)

HVCMOS 35v1 Detector Characterization Using an IR eTCT Setup

CERN Document Server

Laroche, Stewart

2015-01-01

Silicon detectors are exposed to very high fluences (in excess of 1E16 particles*cm-2) in experiments like ATLAS and CMS, so it is paramount that their behavior is understood even after irradiation. To that end, irradiated prototype HVCMOS detectors were characterized using eTCT and IV curves. It was found that acceptor removal via irradiation increased the size of the charge collection region. At sufficient fluences, trap introduction became the dominant effect, and the charge collection region shrinks again.

Deep defect levels in standard and oxygen enriched silicon detectors before and after **6**0Co-gamma-irradiation

CERN Document Server

Stahl, J; Lindström, G; Pintilie, I

2003-01-01

Capacitance Deep Level Transient Spectroscopy (C-DLTS) measurements have been performed on standard and oxygen-doped silicon detectors manufactured from high-resistivity n-type float zone material with left angle bracket 111 right angle bracket and left angle bracket 100 right angle bracket orientation. Three different oxygen concentrations were achieved by the so-called diffusion oxygenated float zone (DOFZ) process initiated by the CERN-RD48 (ROSE) collaboration. Before the irradiation a material characterization has been performed. In contrast to radiation damage by neutrons or high- energy charged hadrons, were the bulk damage is dominated by a mixture of clusters and point defects, the bulk damage caused by **6**0Co-gamma-radiation is only due to the introduction of point defects. The dominant electrically active defects which have been detected after **6**0Co-gamma-irradiation by C-DLTS are the electron traps VO//i, C//iC//s, V//2( = /-), V //2(-/0) and the hole trap C//i O//i. The main difference betwe...

Performance of irradiated CVD diamond micro-strip sensors

Energy Technology Data Exchange (ETDEWEB)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D. E-mail: dirk.meier@cern.ch; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.; Plano, R.; Somalwar, S.V.; Thomson, G.B

2002-01-11

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article, we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a {beta}-source and the performance before and after intense (>10{sup 15}/cm{sup 2}) proton- and pion-irradiations. We find that low dose irradiation increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiation with protons 2.2x10{sup 15} p/cm{sup 2} lowers the signal-to-noise ratio slightly. Intense irradiation with pions 2.9x10{sup 15} {pi}/cm{sup 2} lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations.

Performance of irradiated CVD diamond micro-strip sensors

CERN Document Server

Adam, W; Bergonzo, P; Bertuccio, G; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Hallewell, G D; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Koeth, T W; Krammer, Manfred; Lo Giudice, A; Lü, R; MacLynne, L; Manfredotti, C; Meier, D; Mishina, M; Moroni, L; Noomen, J; Oh, A; Pan, L S; Pernicka, Manfred; Peitz, A; Perera, L P; Pirollo, S; Procario, M; Riester, J L; Roe, S; Rousseau, L; Rudge, A; Russ, J; Sala, S; Sampietro, M; Schnetzer, S R; Sciortino, S; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trischuk, W; Tromson, D; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Wetstein, M; White, C; Zeuner, W; Zöller, M

2002-01-01

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a $\\beta$-source and the performance before and after intense ($>10^{15}/{\\rm cm^2}$) proton- and pion-irradiations. We find that low dose irradiations increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiations with protons ($2.2\\times 10^{15}~p/{\\rm cm^2}$) lowers the signal-to-noise ratio slightly. Intense irradiation with pions ($2.9\\times 10^{15}~\\pi/{\\rm cm^2}$) lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations.

Output characteristics of piezoelectric lead zirconate titanate detector using high-energy heavy-ion beam

International Nuclear Information System (INIS)

Takechi, Seiji; Sekiguchi, Masahiro; Miyachi, Takashi; Kobayashi, Masanori; Hattori, Maki; Okudaira, Osamu; Shibata, Hiromi; Fujii, Masayuki; Okada, Nagaya; Murakami, Takeshi; Uchihori, Yukio

2014-01-01

A radiation detector fabricated using piezoelectric lead zirconate titanate (PZT) has been studied by irradiating it with a 400 MeV/n xenon (Xe) beam. The beam diameter was controlled to change the irradiation conditions. It was found that the magnitude of the output observed from the PZT detector may be related to the number of Xe ions per unit area per unit time within the limits of the experimental conditions. -- Highlights: • The performance of PZT detector was studied by irradiation of a 400 MeV/n Xe beam. • The beam diameter was controlled to change the irradiation conditions. • By the control, the number of Xe ions per one pulse was changed from ∼500 to ∼1500. • The output of the PZT detector was not always larger with more intense beam. • The energy of Xe ions per unit area per unit time may determine the output

Comparative study of Si diodes for gamma radiation dosimetry

International Nuclear Information System (INIS)

Pascoalino, Kelly Cristina da Silva

2010-01-01

In this work it is presented the comparative study of Si diodes response for gamma radiation dosimetry. The diodes investigated, grown by float zone (Fz) and magnetic Czochralski (MCz) techniques, were processed at the Physics Institute of Helsinki University in the framework of the research and development of rad-hard silicon devices. To study the dosimetric response of these diodes they were connected in the photovoltaic mode to the input of a digital electrometer to measure the photocurrent signal due to the incidence of gamma-rays from a 60 Co source (Gammacell 220). The dosimetric parameter utilized to study the response of these devices was the charge, obtained trough the integration of the current signals, as a function of the absorbed dose. Studies of the influence of the pre-irradiation procedures on both sensitivity and stability of these diodes showed that the sensitivity decreased with the total absorbed dose but after a preirradiation of about 873 kGy they became more stable. Radiation damage effects eventually produced in the devices were monitored trough dynamic current and capacitance measurements after each irradiation step. Both samples also exhibited good response reproducibility, 2,21% (Fz) and 2,94% (MCz), obtained with 13 consecutive measurements of 15 kGy compared with the equivalent 195 kGy absorbed dose in one step of irradiation. It is important to note that these results are better than those obtained with routine polymethylmethacrylate (PMMA) dosimeters used in radiation processing dosimetry. (author)

Characterisation of Silicon Timing Detectors for the RD50 Collaboration

CERN Document Server

Immig, David Maximilian

2017-01-01

Increasing pile-up and irradiation following with the high luminosity upgrade of the LHC, demands the development of improved semiconductor detectors. The former problem can be reduced by more precise time information, which can be obtained using a future detector based on the low gain avalanche diode (LGAD). LGADs are studied by the RD50-Collaboration, which studies the characteristics of semiconductor devices to improve these for future requirements of high energy physics. This reports is engaged with the process to characterise semiconductor detectors, specially LGADs, with capacitance-voltage and current-voltage measurements as well as transient current techniques of un- and irradiated semiconductor devices.

Studies on nitrogen mapping by various CR-39 track detectors

Energy Technology Data Exchange (ETDEWEB)

Somogyi, G.; Varga, Zs.; Hunyadi, I.; Freyer, K.; Treutler, H.Ch.

1986-01-01

The use of CR-39 track detectors for nitrogen distribution measurements via the /sup 14/N(n,p)/sup 14/C reaction is studied. The proton detection properties of different CR-39 products have been analyzed. The variation of background track density induced in the bulk of detectors is examined under different conditions of neutron irradiation. Analysis of our experimental data has led to the conclusion that the sources of proton background tracks are the fast neutron component of the neutron source, chlorine impurities in the detector and nitrogen diffused from the air into the upper layer of the detector. Efforts have been made to decrease the nitrogen content of diffusion origin by removing the upper detector layer and by outgassing the CR-39 sheet in vacuum before irradiation. Finally the ''signal/noise'' ratio for a steel specimen and the sensitivity of nitrogen determination are given.

Scanner and irradiation: optimization of protocols

International Nuclear Information System (INIS)

Duchemin, J.; Martine-Rollet, B.; Lienart, S.; Mobailly, M.; Florin, J.P.; Beregi, J.P.; Puech, N.

2006-01-01

The irradiation of the patient or the personnel increased with the arrival of the multi-detector scanners. The objective of this work is to realize a didactic poster to inform and make sensitive on the irradiation with scan so that to propose solutions of protection. (N.C.)

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.

Progress towards vertical transport study of proton-irradiated InAs/GaSb type-II strained-layer superlattice materials for space-based infrared detectors using magnetoresistance measurements

Science.gov (United States)

Malone, Mitchell C.; Morath, Christian P.; Fahey, Stephen; Klein, Brianna; Cowan, Vincent M.; Krishna, Sanjay

2015-09-01

InAs/GaSb type-II strained-layer superlattice (T2SLS) materials are being considered for space-based infrared detector applications. However, an inadequate understanding of the role of carrier transport, specifically the vertical mobility, in the radiation tolerance of T2SLS detectors remains. Here, progress towards a vertical transport study of proton-irradiated, p-type InAs/GaSb T2SLS materials using magnetoresistance measurements is reported. Measurements in the growth direction of square mesas formed from InAs/GaSb superlattice material were performed using two distinct contact geometries in a Kelvin mode setup at variable magnetic fields, ranging from -9 T to 9 T, and temperatures, ranging from 5 K and 300 K. The results here suggested multi-carrier conduction and a field-dependent series resistance from the contact layer were present. The implications of these results and the plans for future magnetoresistance measurements on proton-irradiated T2SLS materials are discussed.

Kit with track detectors aiming at didactic

International Nuclear Information System (INIS)

Cesar, M.F.; Koskinas, M.F.

1988-01-01

The kit intends to improve the possibilities in performing experiments of Nuclear Physics in Modern Physics Laboratories of Physics Course introducing the solid state nuclear track detectors. In these materials the passage of heavily ionizing nuclear particles creates paths (tracks) that may be revealed and made visible in an optical microscope. By the help of the kit several experiments and/or demonstrations may be performed. The kit contains solid state nuclear track detectors unirradiated and irradiated, irradiated etched and uneteched sheets; an alpha source of 241 Am and an instrution text with photomicrographs. To use the kit the laboratory must have an ordinary optical microscope. (author) [pt

Vibration of signal wires in wire detectors under irradiation

International Nuclear Information System (INIS)

Bojko, I.R.; Shelkov, G.A.; Dodonov, V.I.; Ignatenko, M.A.; Nikolenko, M.Yu.

1995-01-01

Radiation-induced vibration of signal wires in wire detectors is found and explained. The phenomenon is based on repulsion of a signal wire with a positive potential and a cloud of positive ions that remains after neutralization of the electron part of the avalanche formed in the course of gas amplification. Vibration with a noticeable amplitude may arise from fluctuations of repulsive forces, which act on the wire and whose sources are numerous ion clusters. A formula is obtained which allows wire oscillations to be estimated for all types of wire detectors. Calculation shows that oscillations of signal wires can be substantial for the coordinate accuracy of a detector working in the limited streamer mode at fluxes over 10 5 particles per second per wire. In the proportional mode an average oscillation amplitude can be as large as 20-30 μm at some detector parameters and external radiation fluxes over 10 5 . The experimental investigations show that the proposed model well describes the main features of the phenomenon. 6 refs., 8 figs

Identification of antimycotic drugs transformation products upon UV exposure

Energy Technology Data Exchange (ETDEWEB)

Casado, Jorge; Rodríguez, Isaac, E-mail: isaac.rodriguez@usc.es; Ramil, María; Cela, Rafael

2015-05-30

Highlights: • Evaluation of antimycotic drugs UV stabilities in model supports. • Simultaneous detection of precursor drugs and transformation products. • Transformation products identification from their scan, accurate MS/MS spectra. • Directed search of identified transformation products in sand and soil samples. • Preliminary toxicity estimations. - Abstract: The reactivity of three imidazolic, environmental persistent antimycotic drugs (clotrimazole, CTZ; ketoconazole, KTZ; and miconazole, MCZ) upon exposure to ultraviolet (UV) radiation is discussed. First, precursor compounds were immobilized in a silicone support which was further exposed to UV light at two different wavelengths: 254 and 365 nm. After solvent desorption, degradation kinetics of the precursor pharmaceuticals, identification of the arising transformation products (TPs) and evaluation of their time-course were investigated by liquid chromatography (LC) with quadrupole time-of-flight (QTOF) mass spectrometry (MS) detection. The three antimycotics displayed similar stabilities when exposed to 254 nm light; however, CTZ was significantly more stable than MCZ and KTZ when irradiated with the 365 nm lamp. TPs identified in silicone supports resulted from de-chlorination, cleavage, intra-molecular cyclization and hydroxylation reactions. Many of these species were also detected when exposing other solid matrices, such as sand and agricultural soil, previously spiked with target compounds, to UV light. The 50% estimated lethal concentration, calculated using the 48-h Daphnia magna test, for the two main TPs of CTZ and MCZ, at both wavelengths, were lower than those corresponding to the precursor drugs.

Identification of antimycotic drugs transformation products upon UV exposure

International Nuclear Information System (INIS)

Casado, Jorge; Rodríguez, Isaac; Ramil, María; Cela, Rafael

2015-01-01

Highlights: • Evaluation of antimycotic drugs UV stabilities in model supports. • Simultaneous detection of precursor drugs and transformation products. • Transformation products identification from their scan, accurate MS/MS spectra. • Directed search of identified transformation products in sand and soil samples. • Preliminary toxicity estimations. - Abstract: The reactivity of three imidazolic, environmental persistent antimycotic drugs (clotrimazole, CTZ; ketoconazole, KTZ; and miconazole, MCZ) upon exposure to ultraviolet (UV) radiation is discussed. First, precursor compounds were immobilized in a silicone support which was further exposed to UV light at two different wavelengths: 254 and 365 nm. After solvent desorption, degradation kinetics of the precursor pharmaceuticals, identification of the arising transformation products (TPs) and evaluation of their time-course were investigated by liquid chromatography (LC) with quadrupole time-of-flight (QTOF) mass spectrometry (MS) detection. The three antimycotics displayed similar stabilities when exposed to 254 nm light; however, CTZ was significantly more stable than MCZ and KTZ when irradiated with the 365 nm lamp. TPs identified in silicone supports resulted from de-chlorination, cleavage, intra-molecular cyclization and hydroxylation reactions. Many of these species were also detected when exposing other solid matrices, such as sand and agricultural soil, previously spiked with target compounds, to UV light. The 50% estimated lethal concentration, calculated using the 48-h Daphnia magna test, for the two main TPs of CTZ and MCZ, at both wavelengths, were lower than those corresponding to the precursor drugs

An investigation of methods for neutron dose measurement in high temperature irradiation fields

Energy Technology Data Exchange (ETDEWEB)

Kosako, Toshisou; Sugiura, Nobuyuki [Tokyo Univ. (Japan); Kudo, Kazuhiko [Kyushu Univ., Fukuoka (Japan)] [and others

2000-10-01

The Japan Atomic Energy Research Institute (JAERI) has been conducting the innovative basic research on high temperature since 1994, which is a series of high temperature irradiation studies using the High Temperature Engineering Test Reactor (HTTR). 'The Task Group for Evaluation of Irradiation Dose under High Temperature Radiation' was founded in the HTTR Utilization Research Committee, which is the promoting body of the innovative basic research. The present report is a summary of investigation which has been made by the Task Group on the present status and subjects of research and development of neutron detectors in high temperature irradiation fields, in view of contributing to high temperature irradiation research using the HTTR. Detectors investigated here in the domestic survey are the following five kinds of in-core detectors: 1) small fission counter, 2) small fission chamber, 3) self-powered detector, 4) activation detector, and 5) optical fiber. In addition, the research and development status in Russia has been investigated. The present report will also be useful as nuclear instrumentation of high temperature gas-cooled reactors. (author)

Ultrafast photoconductor detector-laser-diode transmitter

International Nuclear Information System (INIS)

Wang, C.L.; Davis, B.A.; Davies, T.J.; Nelson, M.A.; Thomas, M.C.; Zagarino, P.A.

1987-01-01

We report the results of an experiment in which we used an ultrafast, photoconductive, radiation detector to drive a fast laser-diode transmitter. When we irradiated the neutron-damaged Cr-doped GaAs detector with 17-MeV electron beams, the temporal response was measured to be less than 30 ps. The pulses from this detector modulated a fast GaAlAs laser diode to transmit the laser output through 30- and 1100-m optical fibers. Preliminary results indicate that 50- and 80-ps time resolutions, respectively, are obtainable with these fibers. We are now working to integrate the photoconductive detector and the laser diode transmitter into a single chip

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.).

Radiation hardness of silicon detectors for collider experiments

International Nuclear Information System (INIS)

Golutvin, I.; Cheremukhin, A.; Fefelova, E.

1995-01-01

The silicon planar detectors before and after fast neutron irradiation ( n o> = 1.35 MeV) at room temperature have been investigated. Maximal neutron fluence has been 8 · 10 13 cm -2 . The detectors have been manufactured of the high resistivity (1 : 10 k Ohm · cm) n-type float-zone silicon (FZ-Si) with the orientation supplied by two different producers: WACKER CHEMITRONIC and Zaporojie Titanium-Magnesium Factory (ZTMF). The influence of fast neutron irradiation of the main parameters of the starting silicon before the technological high temperature treatment has been investigated as well. 30 refs., 17 figs., 5 tabs

Calibration and alignment of the CMS silicon tracking detector

International Nuclear Information System (INIS)

Stoye, M.

2007-07-01

The Large Hadron Collider (LHC) will dominate the high energy physics program in the coming decade. The discovery of the standard model Higgs boson and the discovery of super-symmetric particles are within the reach at the energy scale explored by the LHC. However, the high luminosity and the high energy of the colliding protons lead to challenging demands on the detectors. The hostile radiation environment requires irradiation hard detectors, where the innermost subdetectors, consisting of silicon modules, are most affected. This thesis is devoted to the calibration and alignment of the silicon tracking detector. Electron test beam data, taken at DESY, have been used to investigate the performance of detector modules which previously were irradiated with protons up to a dose expected after 10 years of operation. The irradiated sensors turned out to be still better than required. The performance of the inner tracking systems will be dominated by the degree to which the positions of the sensors can be determined. Only a track based alignment procedure can reach the required precision. Such an alignment procedure is a major challenge given that about 50000 geometry constants need to be measured. Making use of the novel χ 2 minimization program Millepede II an alignment strategy has been developed in which all detector components are aligned simultaneously, as many sources of information as possible are used, and all correlations between the position parameters of the detectors are taken into account. Utilizing simulated data, a proof of concept of the alignment strategy is shown. (orig.)

Calibration and alignment of the CMS silicon tracking detector

Energy Technology Data Exchange (ETDEWEB)

Stoye, M.

2007-07-15

The Large Hadron Collider (LHC) will dominate the high energy physics program in the coming decade. The discovery of the standard model Higgs boson and the discovery of super-symmetric particles are within the reach at the energy scale explored by the LHC. However, the high luminosity and the high energy of the colliding protons lead to challenging demands on the detectors. The hostile radiation environment requires irradiation hard detectors, where the innermost subdetectors, consisting of silicon modules, are most affected. This thesis is devoted to the calibration and alignment of the silicon tracking detector. Electron test beam data, taken at DESY, have been used to investigate the performance of detector modules which previously were irradiated with protons up to a dose expected after 10 years of operation. The irradiated sensors turned out to be still better than required. The performance of the inner tracking systems will be dominated by the degree to which the positions of the sensors can be determined. Only a track based alignment procedure can reach the required precision. Such an alignment procedure is a major challenge given that about 50000 geometry constants need to be measured. Making use of the novel {chi}{sup 2} minimization program Millepede II an alignment strategy has been developed in which all detector components are aligned simultaneously, as many sources of information as possible are used, and all correlations between the position parameters of the detectors are taken into account. Utilizing simulated data, a proof of concept of the alignment strategy is shown. (orig.)

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)

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)

TCAD simulation of Low Gain Avalanche Detectors

Science.gov (United States)

Dalal, Ranjeet; Jain, Geetika; Bhardwaj, Ashutosh; Ranjan, Kirti

2016-11-01

In the present work, detailed simulation using Technology Computer Aided Design (TCAD) tool, Silvaco for non-irradiated and irradiated LGAD (Low Gain Avalanche Detector) devices has been carried out. The effects of different design parameters and proton irradiation on LGAD operation are discussed in detail. An already published effective two trap bulk damage model is used to simulate the radiation damage without implementing any acceptor removal term. The TCAD simulation for irradiated LGAD devices produce decreasing gain with increasing fluence, similar to the measurement results. The space charge density and electric field distribution are used to illustrate the possible reasons for the degradation of gain of the irradiated LGAD devices.

TCAD simulation of Low Gain Avalanche Detectors

Energy Technology Data Exchange (ETDEWEB)

Dalal, Ranjeet; Jain, Geetika; Bhardwaj, Ashutosh, E-mail: ashutosh.bhardwaj@cern.ch; Ranjan, Kirti

2016-11-11

In the present work, detailed simulation using Technology Computer Aided Design (TCAD) tool, Silvaco for non-irradiated and irradiated LGAD (Low Gain Avalanche Detector) devices has been carried out. The effects of different design parameters and proton irradiation on LGAD operation are discussed in detail. An already published effective two trap bulk damage model is used to simulate the radiation damage without implementing any acceptor removal term. The TCAD simulation for irradiated LGAD devices produce decreasing gain with increasing fluence, similar to the measurement results. The space charge density and electric field distribution are used to illustrate the possible reasons for the degradation of gain of the irradiated LGAD devices.

TCAD simulation of Low Gain Avalanche Detectors

International Nuclear Information System (INIS)

Dalal, Ranjeet; Jain, Geetika; Bhardwaj, Ashutosh; Ranjan, Kirti

2016-01-01

In the present work, detailed simulation using Technology Computer Aided Design (TCAD) tool, Silvaco for non-irradiated and irradiated LGAD (Low Gain Avalanche Detector) devices has been carried out. The effects of different design parameters and proton irradiation on LGAD operation are discussed in detail. An already published effective two trap bulk damage model is used to simulate the radiation damage without implementing any acceptor removal term. The TCAD simulation for irradiated LGAD devices produce decreasing gain with increasing fluence, similar to the measurement results. The space charge density and electric field distribution are used to illustrate the possible reasons for the degradation of gain of the irradiated LGAD devices.

A neutron activation detector

International Nuclear Information System (INIS)

Ambardanishvili, T.S.; Kolomiitsev, M.A.; Zakharina, T.Y.; Dundua, V.J.; Chikhladze, N.V.

1973-01-01

The present invention concerns a neutron activation detector made from a moulded and hardened composition. According to the invention, that composition contains an activable substance constituted by at least two chemical elements and/or compounds of at least two chemical elements. Each of these chemical elements is capable of reacting with the neutrons forming radio-active isotopes with vatious levels of energy during desintegration. This neutron detector is mainly suitable for measuring integral thermal neutron and fast neutron fluxes during irradiation of the sample, and also for measuring the intensities of neutron fields [fr

Polarization effect of CdZnTe imaging detector based on high energy γ source

International Nuclear Information System (INIS)

Li Miao; Xiao Shali; Wang Xi; Shen Min; Zhang Liuqiang; Cao Yulin; Chen Yuxiao

2011-01-01

The inner electric potential distribution of CdZnTe detector was derived by applying poisson equation with the first type boundary condition, and the polarization effect of CdZnTe pixellated detector for imaging 137 Cs γ source was investigated. The results of numerical calculation and experiment indicate that electric potential distribution is mainly influenced by applied bias for low charge density in CdZnTe crystal and, in turn, there is linear relationship between electric potential distribution and applied bias that induces uniform electric field under low irradiated flux. However, the electric potential appears polarization phenomenon, and the electric field in CdZnTe crystal is distorted when CdZnTe detector is under high irradiated flux. Consequently, charge carriers in CdZnTe crystal drift towards the edge pixels of irradiated region, and hence, the shut-off central pixels are surrounded by a ring of low counting pixels. The polarization effect indeed deteriorates the performance of CdZnTe detector severely and the event counts of edge pixels for irradiated region reduce about 70%. (authors)

Performance studies under high irradiation of resistive bulk-micromegas chambers at the CERN Gamma Irradiation Facility

CERN Document Server

Sidiropoulou, Ourania; Bortfeldt, J; Farina, E; Iengo, P; Longo, L; Sidiropoulou, O; Wotschack, J

2017-01-01

Radiation studies on several resistive bulk-Micromegas chambers produced at CERN will be viewed in this document. Two resistive bulk-Micromegas chambers have been installed at the CERN Gamma Irradiation Facility (GIF++) exposed to an intense gamma irradiation with the aim of evaluating the detector behaviour under high irradiation and carrying out a long-term age- ing study. The chambers under study have an active area of 10 x 10 cm 2 , a strip pitch of 400 m m , an ampli- fication gap of 128 m m , and a drift gap of 5 mm. The results on the detector performance as a function of the photon flux up to 44 MHz/cm 2 will be shown as well as the ageing properties as function of the integrated charge and the current intensity and its stability with time. In addition, the results of the efficiency measurements before, during, and after the irradiation will also be presented as a function of the amplification voltage at which the chambers are operated.

Nuclear track detector kit for use in teaching

Energy Technology Data Exchange (ETDEWEB)

Medveczky, L.; Somogyi, G.; Nagy, M.

1986-01-01

By the use of solid state nuclear track detectors (SSNTDs) one may carry out several useful and impressive educational experiments and demonstrations to illustrate different phenomena when teaching of nuclear physics. Realizing this situation the authors have published, since 1970, reports on several experiments for teaching demonstrations. Based on the authors instructions, a factory in Hungary (TANFRT, National Manufacturers and Suppliers of School Equipment, Budapest) constructed a kit for the use of nuclear track detectors in teaching. The portable kit contains the following items: alpha-emitting weak sources, solid state nuclear track detectors (unirradiated, irradiated, unetched and etched sheets), simple tools for carrying out experiments (facilities for irradiation and etching, etc.), slides showing photos of typical etch-tracks of light and heavy nuclei, user manual. By the help of the kit both pupils and teachers can perform various useful experiments and/or demonstrations.

Study of intense pulse irradiation effects on silicon targets considered as ground matter for optical detectors; Etude des effets d`irradiations pulsees intenses sur des cibles de silicium considere en tant que materiau de base pour detecteurs optiques

Energy Technology Data Exchange (ETDEWEB)

Muller, O

1994-12-01

This study aim was centered on morphological and structural alterations induced by laser irradiation on silicon targets considered as ground matter for optical detectors. First we recalled the main high light intensity effects on the condensed matter. Then we presented the experimental aspects. The experimental studies were achieved on two sample types: SiO{sub 2}/Si and Si. Two topics were studied: the defect chronology according to wavelength and pulse length, and the crystalline quality as well as the structure defects of irradiated zones by Raman spectroscopy. Finally, irradiation of Si targets by intense pulsed beams may lead to material fusion. This phenomenon is particularly easy when the material is absorbent, when the pulse is short and when the material is superficially oxidized. (MML). 204 refs., 93 figs., 21 tabs., 1 appendix.

Isotropic irradiation of detectors from point sources

DEFF Research Database (Denmark)

Aage, Helle Karina

1997-01-01

NaI(Tl) scintillator detectors have been exposed to gamma rays from 8 different point sources from different directions. Background and backscatter of gamma-rays from the surroundings have been subtracted in order to produce clean spectra. By adding spectra obtained from exposures from different ...

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.)

Ultrafast photoconductive detector-laser-diode transmitter

International Nuclear Information System (INIS)

Wang, C.L.; Davies, T.J.; Nelson, M.A.; Thomas, M.C.; Zagarino, P.A.; Davis, B.A.

1987-01-01

The authors report the results of an experiment in which they used an ultrafast, photoconductive, radiation detector to drive a fast laser-diode transmitter. When they irradiated the neutron-damaged Cr-doped Ga/As detector with 17-MeV electron beams, the temporal response of was measured to be less than 30 ps. The pulses from this detector modulated a fast GaAlAs laser diode to transmit the laser output through 30- and 1100-m optical fibers. Preliminary results indicate that 50- and 80-ps time resolutions, respectively, are obtainable with these fibers. They are now working to integrate the photoconductive detector and the laser diode transmitter into a single chip

Estimation of track registration efficiency in solution medium and study of gamma irradiation effects on the bulk-etch rate and the activation energy for bulk etching of CR-39 (DOP) Solid State Nuclear Track Detector

International Nuclear Information System (INIS)

Kalsi, P.C.

2010-01-01

The fission track registration efficiency of diethylene glycol bis allyl carbonate (dioctyl phthalate doped) (CR-39 (DOP)) solid state nuclear track detector (SSNTD) in solution medium (K wet ) has been experimentally determined and is found to be (9.7 ± 0.5).10 -4 cm. This is in good agreement with the values of other SSNTDs. The gamma irradiation effects in the dose range of 50.0-220.0 kGy on the bulk etch rate, V b and the activation energy for bulk etching, E of this solid state nuclear track detector (SSNTD) have also been studied. It is observed that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation

Improved photon detector

International Nuclear Information System (INIS)

Zermeno, A.; Marsh, L.M.

1981-01-01

Apparatus and methods used to obtain image information from modulation of a uniform flux. A multi-layered detector apparatus is disclosed which comprises a first conductive layer having two sides, a photoconductive layer thick enough to obtain a desired level of sensitivity and resolution of the detector apparatus when the detector apparatus is exposed to radiation of known energy, one side of the photoconductive layer being integrally affixed to and in electrical contact with one side of the first conductive layer, an insulating layer having two sides that is a phosphor that will emit light when irradiated by x-rays, one side of the insulating layer being affixed to the other side of the photoconductive layer and a transparent conductive layer having two sides, one side of the transparent conductive layer being affixed to the other side of the insulating layer. (author)

Hexagonal boron nitride neutron detectors with high detection efficiencies

Science.gov (United States)

Maity, A.; Grenadier, S. J.; Li, J.; Lin, J. Y.; Jiang, H. X.

2018-01-01

Neutron detectors fabricated from 10B enriched hexagonal boron nitride (h-10BN or h-BN) epilayers have demonstrated the highest thermal neutron detection efficiency among solid-state neutron detectors to date at about 53%. In this work, photoconductive-like vertical detectors with a detection area of 1 × 1 mm2 were fabricated from 50 μm thick free-standing h-BN epilayers using Ni/Au and Ti/Al bilayers as ohmic contacts. Leakage currents, mobility-lifetime (μτ) products under UV photoexcitation, and neutron detection efficiencies have been measured for a total of 16 different device configurations. The results have unambiguously identified that detectors incorporating the Ni/Au bilayer on both surfaces as ohmic contacts and using the negatively biased top surface for neutron irradiation are the most desired device configurations. It was noted that high growth temperatures of h-10BN epilayers on sapphire substrates tend to yield a higher concentration of oxygen impurities near the bottom surface, leading to a better device performance by the chosen top surface for irradiation than by the bottom. Preferential scattering of oxygen donors tends to reduce the mobility of holes more than that of electrons, making the biasing scheme with the ability of rapidly extracting holes at the irradiated surface while leaving the electrons to travel a large average distance inside the detector at a preferred choice. When measured against a calibrated 6LiF filled micro-structured semiconductor neutron detector, it was shown that the optimized configuration has pushed the detection efficiency of h-BN neutron detectors to 58%. These detailed studies also provided a better understanding of growth-mediated impurities in h-BN epilayers and their effects on the charge collection and neutron detection efficiencies.

Technology development of p-type microstrip detectors with radiation hard p-spray isolation

International Nuclear Information System (INIS)

Pellegrini, G.; Fleta, C.; Campabadal, F.; Diez, S.; Lozano, M.; Rafi, J.M.; Ullan, M.

2006-01-01

A technology for the fabrication of p-type microstrip silicon radiation detectors using p-spray implant isolation has been developed at CNM-IMB. The p-spray isolation has been optimized in order to withstand a gamma irradiation dose up to 50 Mrad (Si), which represents the ionization radiation dose expected in the middle region of the SCT-Atlas detector of the future Super-LHC during 10 years of operation. The best technological options for the p-spray implant were found by using a simulation software package and dedicated calibration runs. Using the optimized technology, detectors have been fabricated in the Clean Room facility of CNM-IMB, and characterized by reverse current and capacitance measurements before and after irradiation. The average full depletion voltage measured on the non-irradiated detectors was V FD =41±3 V, while the leakage current density for the microstrip devices at V FD +20 V was 400 nA/cm 2

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...

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).

Diamond detector technology: status and perspectives

CERN Document Server

Kagan, Harris; Artuso, M; Bachmair, F; Bäni, L; Bartosik, M; Beacham, J; Beck, H P; Bellini,, V; Belyaev, V; Bentele, B; Berdermann, E; Bergonzo, P; Bes, A; Brom, J-M; Bruzzi, M; Cerv, M; Chiodini, G; Chren, D; Cindro, V; Claus, G; Collot, J; Cumalat, J; Dabrowski, A; D'Alessandro, R; De Boer, W; Dehning, B; Dorfer, C; Dunser, M; Eremin, V; Eusebi, R; Forcolin, G; Forneris, J; Frais-Kölbl, H; Gan, K K; Gastal, M; Giroletti, C; Goffe, M; Goldstein, J; Golubev, A; Gorišek, A; Grigoriev, E; Grosse-Knetter, J; Grummer, A; Gui, B; Guthoff, M; Haughton, I; Hiti, B; Hits, D; Hoeferkamp, M; Hofmann, T; Hosslet, J; Hostachy, J-Y; Hügging, F; Hutton, C; Jansen, H; Janssen, J; Kanxheri, K; Kasieczka, G; Kass, R; Kassel, F; Kis, M; Kramberger, G; Kuleshov, S; Lacoste, A; Lagomarsino, S; Lo Giudice, A; Lukosi, E; Maazouzi, C; Mandic, I; Mathieu, C; Mcfadden, N; Menichelli, M; Mikuž, M; Morozzi, A; Moss, J; Mountain, R; Murphy, S; Muškinja, M; Oh, A; Oliviero, P; Passeri, D; Pernegger, H; Perrino, R; Picollo, F; Pomorski, M; Potenza, R; Quadt, A; Re, A; Reichmann, M; Riley, G; Roe, S; Sanz, D; Scaringella, M; Schaefer, D; Schmidt, C J; Schnetzer, S; Schreiner, T; Sciortino, S; Scorzoni, A; Seidel, S; Servoli, L; Sopko, B; Sopko, V; Spagnolo, S; Spanier, S; Stenson, K; Stone, R; Sutera, C; Taylor, Aaron; Traeger, M; Tromson, D; Trischuk, W; Tuve, C; Uplegger, L; Velthuis, J; Venturi, N; Vittone, E; Wagner, Stephen; Wallny, R; Wang, J C; Weingarten, J; Weiss, C; Wengler, T; Wermes, N; Yamouni, M; Zavrtanik, M

2017-01-01

The status of material development of poly-crystalline chemical vapor deposition (CVD) diamond is presented. We also present beam test results on the independence of signal size on incident par-ticle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition the first beam test results from 3D detectors made with poly-crystalline CVD diamond are presented. Finally the first analysis of LHC data from the ATLAS Diamond Beam Monitor (DBM) which is based on pixelated poly-crystalline CVD diamond sensors bump-bonded to pixel readout elec-tronics is shown.

Radiation hardness of a single crystal CVD diamond detector for MeV energy protons

Energy Technology Data Exchange (ETDEWEB)

Sato, Yuki, E-mail: y.sato@riken.jp [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Shimaoka, Takehiro; Kaneko, Junichi H. [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Murakami, Hiroyuki [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Isobe, Mitsutaka; Osakabe, Masaki [National Institute for Fusion Science, 322-6, Oroshi-cho Toki-city, Gifu 509-5292 (Japan); Tsubota, Masakatsu [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Ochiai, Kentaro [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Chayahara, Akiyoshi; Umezawa, Hitoshi; Shikata, Shinichi [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

2015-06-01

We have fabricated a particle detector using single crystal diamond grown by chemical vapor deposition. The irradiation dose dependence of the output pulse height from the diamond detector was measured using 3 MeV protons. The pulse height of the output signals from the diamond detector decreases as the amount of irradiation increases at count rates of 1.6–8.9 kcps because of polarization effects inside the diamond crystal. The polarization effect can be cancelled by applying a reverse bias voltage, which restores the pulse heights. Additionally, the radiation hardness performance for MeV energy protons was compared with that of a silicon surface barrier detector.

Effects of DD and DT neutron irradiation on some Si devices for fusion diagnostics

International Nuclear Information System (INIS)

Tanimura, Y.; Iida, T.

1998-01-01

In order to examine the difference in the irradiation effects on Si devices between DT and DD neutrons, CCD image sensors, memory ICs and a Si detector were irradiated with neutrons from a deuteron accelerator. The transient effects (i.e. neutron-induced background noises) and permanent effects (i.e. neutron damage) on them were in situ measured during irradiation. Regarding the transient effects, brightening spot noises, soft-error upsets and induced-charge noises were measured for the CCDs, memory ICs and Si detector, respectively. As for the permanent effect, the number of damaged cells of the CCDs and the leakage current of the Si detector increased with neutron fluence. Also we developed a Monte-Carlo code with the TRIM code to evaluate the correlation of DT and DD neutron effects on Si devices. The calculated correlation factor of DT and DD neutron damage for Si devices agreed approximately with the correlation factor obtained from the irradiation experiments on the CCDs and Si detector. (orig.)

Effects of DD and DT neutron irradiation on some Si devices for fusion diagnostics

Science.gov (United States)

Tanimura, Yoshihiko; Iida, Toshiyuki

1998-10-01

In order to examine the difference in the irradiation effects on Si devices between DT and DD neutrons, CCD image sensors, memory ICs and a Si detector were irradiated with neutrons from a deuteron accelerator. The transient effects (i.e. neutron-induced background noises) and permanent effects (i.e. neutron damage) on them were in situ measured during irradiation. Regarding the transient effects, brightening spot noises, soft-error upsets and induced-charge noises were measured for the CCDs, memory ICs and Si detector, respectively. As for the permanent effect, the number of damaged cells of the CCDs and the leakage current of the Si detector increased with neutron fluence. Also we developed a Monte-Carlo code with the TRIM code to evaluate the correlation of DT and DD neutron effects on Si devices. The calculated correlation factor of DT and DD neutron damage for Si devices agreed approximately with the correlation factor obtained from the irradiation experiments on the CCDs and Si detector.

Detector Control System for CMS RPC at GIF++

CERN Document Server

Gul, Muhammad

2016-01-01

In the framework of the High Luminosity LHC upgrade program, the CMS muon groupbuilt several different RPC prototypes that are now under test at the new CERN Gamma Irradiation Facility (GIF++). A dedicated Detector Control System has been developed using the WinCC-OA tool to control and monitor these prototype detectors and to store the measured parameters data.

Nuclear track detector kit for use in teaching

International Nuclear Information System (INIS)

Medveczky, L.; Somogyi, G.

1986-01-01

By the use of solid state nuclear track detectors (SSNTDs) one may carry out several useful and impressive educational experiments and demonstrations to illustrate different phenomena when teaching of nuclear physics. Realizing this situation the authors have published, since 1970, reports on several experiments for teaching demonstrations. Based on the authors instructions, a factory in Hungary (TANFRT, National Manufacturers and Suppliers of School Equipment, Budapest) constructed a kit for the use of nuclear track detectors in teaching. The portable kit contains the following items: alpha-emitting weak sources, solid state nuclear track detectors (unirradiated, irradiated, unetched and etched sheets), simple tools for carrying out experiments (facilities for irradiation and etching, etc.), slides showing photos of typical etch-tracks of light and heavy nuclei, user manual. By the help of the kit both pupils and teachers can perform various useful experiments and/or demonstrations. (author)

Fast neutron detection at near-core location of a research reactor with a SiC detector

Science.gov (United States)

Wang, Lei; Jarrell, Josh; Xue, Sha; Tan, Chuting; Blue, Thomas; Cao, Lei R.

2018-04-01

The measurable charged-particle produced from the fast neutron interactions with the Si and C nucleuses can make a wide bandgap silicon carbide (SiC) sensor intrinsically sensitive to neutrons. The 4H-SiC Schottky detectors have been fabricated and tested at up to 500 °C, presenting only a slightly degraded energy resolution. The response spectrum of the SiC detectors were also obtained by exposing the detectors to external neutron beam irradiation and at a near-core location where gamma-ray field is intense. The fast neutron flux of these two locations are ∼ 4 . 8 × 104cm-2 ṡs-1 and ∼ 2 . 2 × 107cm-2 ṡs-1, respectively. At the external beam location, a Si detector was irradiated side-by-side with SiC detector to disjoin the neutron response from Si atoms. The contribution of gamma ray, neutron scattering, and charged-particles producing reactions in the SiC was discussed. The fast neutron detection efficiencies were determined to be 6 . 43 × 10-4 for the external fast neutron beam irradiation and 6 . 13 × 10-6 for the near-core fast neutron irradiation.

Diamond detectors for high energy physics experiments

Science.gov (United States)

Bäni, L.; Alexopoulos, A.; Artuso, M.; Bachmair, F.; Bartosik, M.; Beacham, J.; Beck, H.; Bellini, V.; Belyaev, V.; Bentele, B.; Berdermann, E.; Bergonzo, P.; Bes, A.; Brom, J.-M.; Bruzzi, M.; Cerv, M.; Chiodini, G.; Chren, D.; Cindro, V.; Claus, G.; Collot, J.; Cumalat, J.; Dabrowski, A.; D'Alessandro, R.; Dauvergne, D.; de Boer, W.; Dorfer, C.; Dünser, M.; Eremin, V.; Eusebi, R.; Forcolin, G.; Forneris, J.; Frais-Kölbl, H.; Gallin-Martel, L.; Gallin-Martel, M. L.; Gan, K. K.; Gastal, M.; Giroletti, C.; Goffe, M.; Goldstein, J.; Golubev, A.; Gorišek, A.; Grigoriev, E.; Grosse-Knetter, J.; Grummer, A.; Gui, B.; Guthoff, M.; Haughton, I.; Hiti, B.; Hits, D.; Hoeferkamp, M.; Hofmann, T.; Hosslet, J.; Hostachy, J.-Y.; Hügging, F.; Hutton, C.; Jansen, H.; Janssen, J.; Kagan, H.; Kanxheri, K.; Kasieczka, G.; Kass, R.; Kassel, F.; Kis, M.; Konovalov, V.; Kramberger, G.; Kuleshov, S.; Lacoste, A.; Lagomarsino, S.; Lo Giudice, A.; Lukosi, E.; Maazouzi, C.; Mandic, I.; Mathieu, C.; Menichelli, M.; Mikuž, M.; Morozzi, A.; Moss, J.; Mountain, R.; Murphy, S.; Muškinja, M.; Oh, A.; Oliviero, P.; Passeri, D.; Pernegger, H.; Perrino, R.; Picollo, F.; Pomorski, M.; Potenza, R.; Quadt, A.; Re, A.; Reichmann, M.; Riley, G.; Roe, S.; Sanz, D.; Scaringella, M.; Schaefer, D.; Schmidt, C. J.; Schnetzer, S.; Sciortino, S.; Scorzoni, A.; Seidel, S.; Servoli, L.; Smith, S.; Sopko, B.; Sopko, V.; Spagnolo, S.; Spanier, S.; Stenson, K.; Stone, R.; Sutera, C.; Tannenwald, B.; Taylor, A.; Traeger, M.; Tromson, D.; Trischuk, W.; Tuve, C.; Uplegger, L.; Velthuis, J.; Venturi, N.; Vittone, E.; Wagner, S.; Wallny, R.; Wang, J. C.; Weingarten, J.; Weiss, C.; Wengler, T.; Wermes, N.; Yamouni, M.; Zavrtanik, M.

2018-01-01

Beam test results of the radiation tolerance study of chemical vapour deposition (CVD) diamond against different particle species and energies is presented. We also present beam test results on the independence of signal size on incident particle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition functionality of poly-crystalline CVD diamond 3D devices was demonstrated in beam tests and 3D diamond detectors are shown to be a promising technology for applications in future high luminosity experiments.

Ion smoke detector

International Nuclear Information System (INIS)

Basset, Georges.

1976-01-01

This invention covers an ion smoke detector in which the capacity that the smoke will cross, in the event of an accident, is irradiated by a very low energy radioactive source. The gas in the containment is thus partially ionised. Smoke in this containment reduces the mobility of the ions, thereby increasing the impedance of the measuring chamber. A leak tight reference chamber that therefore receives no smoke is added to the measuring chamber. This chamber is filled with the same gas as that present in the measuring chamber and undergoes the same irradiation. It is of course subjected to the same conditions of temperature, atmospheric pressure and hygrometry as the measuring chamber. This makes it possible to break free from the fluctuations of the impedance of the chamber which would seem to be due to these interferences. One only radioactive source irradiates the measuring chamber and the reference chamber. The measuring chamber is in the shape of a cylinder open at one end and the reference chamber is annular and encompasses the measuring chamber. Provision is made for detecting an increase in the potential across the terminals of the measuring chamber in relation to the reference chamber, which is characteristic of the presence of smoke and other provisions separate from the former for dectecting a reduction in potential between the electrodes of the first ionisation chamber, which is characteristic of a change in the detector [fr

Depth sensitivity of Lexan polycarbonate detector

CERN Document Server

Awad, E M

1999-01-01

The dependence of the registration sensitivity of Lexan polycarbonate with depth inside the detector was studied. Samples of Lexan from General Electric were irradiated to two long range ions. These were Ni and Au ions with a projectile energy of 0.3 and 1 GeV/n. Two independent techniques, the track-diameter technique (TDT) and the track profile technique (TPT), were used. The registration sensitivity was measured at depths of 7, 10, 15, 18, 20, 28, 35 and 40 mu m inside the detector. The results of the two techniques show that the detector sensitivity decreases gradually with the depth inside the detector. It reaches 20 % less compared to sensitivity at the surface after 40 mu m have been removed.

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

Performance of the ALIBAVA portable readout system with irradiated and non-irradiated microstrip silicon sensors

International Nuclear Information System (INIS)

Marco-Hernadez, R.

2009-01-01

A readout system for microstrip silicon sensors has been developed as a result of collaboration among the University of Liverpool, the CNM of Barcelona and the IFIC of Valencia. The name of this collaboration is ALIBAVA and it is integrated in the RD50 Collaboration. This system is able to measure the collected charge in one or two microstrip silicon sensors by reading out all the channels of the sensor(s), up to 256, as an analogue measurement. The system uses two Beetle chips to read out the detector(s). The Beetle chip is an analogue pipelined readout chip used in the LHCb experiment. The system can operate either with non-irradiated and irradiated sensors as well as with n-type and p-type microstrip silicon sensors. Heavily irradiated sensors will be used at the SLHC, so this system is being to research the performance of microstrip silicon sensors in conditions as similar as possible to the SLHC operating conditions. The system has two main parts: a hardware part and a software part. The hardware part acquires the sensor signals either from external trigger inputs, in case of a radioactive source setup is used, or from a synchronised trigger output generated by the system, if a laser setup is used. This acquired data is sent by USB to be stored in a PC for a further processing. The hardware is a dual board based system. The daughterboard is a small board intended for containing two Beetle readout chips as well as fan-ins and detector support to interface the sensors. The motherboard is intended to process the data, to control the whole hardware and to communicate with the software by USB. The software controls the system and processes the data acquired from the sensors in order to store it in an adequate format file. The main characteristics of the system will be described. Results of measurements acquired with n-type and p-type irradiated and non-irradiated detectors using both the laser and the radioactive source setup will be also presented and discussed

UV sensitivity of various solid state detectors

International Nuclear Information System (INIS)

Knezevic, Zeljka; Ranogajec-Komor, Maria; Miljanic, Saveta

2008-01-01

Full text: The light sensitivity is an important characteristic of solid state passive dosimeters used in individual, clinical and environmental dosimetry. Light sensitivity stands for the response directly induced by visible or UV light in a fully annealed material. For the above mentioned applications a negligible light sensitivity is an advantage. However, high light sensitivity and linear response allows the use of detectors as UV dosimeters. For this purpose various TL detectors and the glass element of the RPL dosemeter type SC-1 were systematically investigated after exposure to UV light (254 and 366 nm) as a function of time. The following solid state detectors were investigated relative to TLD-100: Li 2 B 4 O 7 :Cu,Ag,P LiF:Mg,Cu,P, LiF:Mg,Cu,Si, Al 2 O 3 :C and the glass element of RPL dosimeter. UV irradiations were performed with Camag UV lamp at 254 nm and at 366 nm. The illumination times were 5, 10 and 20 minutes. Day light illumination was also carried out at room temperature over time period of several hours up to 2 weeks. The UV light response of each detector was compared to the response obtained after irradiation with 137 Cs. Al 2 O 3 :C, showed high light sensitivity; after 10 minutes illumination with 254 nm UV light the response was equivalent to 130 mGy 137 Cs gamma irradiation. The 254 nm UV response of LiF:Mg,Cu,P (GR-200 A), as well as TLD-700H and Li 2 B 4 O 7 :Cu,Ag,P were proportional to the time of illumination. The responses after 10 min UV illumination were equivalent to 0.001 mGy, 0.01 mGy and 0.1 mGy 137 Cs gamma irradiation, respectively. The complete SC-1 RPL dosimeter is insensitive to light because the glass element is encapsulated in light protected holder throughout the automatic evaluation process following the annealing (irradiation, preheat, readout). The responses of the previously annealed glass element after 20 min illumination with 254 nm and 366 nm UV light were equivalent to 45μSv and 3 μSv of 137 Cs gamma

Effect of SiO$_{2}$ passivating layer in segmented silicon planar detectors on the detector response

CERN Document Server

Verbitskaya, Elena; Eremin, Vladimir; Golubkov, S; Konkov, K; Roe, Shaun; Ruggiero, G; Sidorov, A; Weilhammer, Peter

2004-01-01

Silicon detectors with a fine segmentation (micropixel and microstrip) are the main type of detectors used in the inner trackers of LHC experiments. Due to the high luminosity of the LHC machines they are required to have a fast response to fit the short shaping time of 25 ns and to be radiation hard. Evaluation of silicon microstrip detectors developed for the ATLAS silicon tracker and carried out under collaboration of CERN and PTI has shown the reversal of the pulse polarity in the detector response to short- range radiation. Since the negative signal is of about 30% of the normal positive one, the effect strongly reduces the charge collection efficiency in irradiated detectors. The investigation presents the consideration on the origin of a negative response in Si microstrip detectors and the experimental proof of the model. The study of the effect has been carried out using "baby" strip detectors with a special design: each strip has a window in a metallization, which covers the p/sup +/ implant. The sca...

Temperature effects on interaction of positive ions with plastic detectors

International Nuclear Information System (INIS)

Mendoza Anaya, D.

1992-01-01

The range of heavy charged particles in matter is dependent mainly on two groups of parameters, one related to the particle characteristics (charge z, mass m, energy E) and the other characterized by the stopping medium (charge z, density ρ). Those two groups are enough to describe the particle energy lost, which is related to the residual range. Research on charge particles registration using solid state nuclear track detectors (SSNTD), probe that environmental parameters affect the stabilization and formation of the tracks. One of those, is the temperature detector which shows an important effect during the irradiation on the characteristics of the tracks produced. In order to study the dependence of track geometry as a function of irradiation temperature, some SSNTD (CR 39 type) were irradiated with α particles and fission fragments. Results of this work show the existence of irradiation temperature effect on the track geometry. It is observed a reduction of length and diameters, as temperature increases. For low irradiation temperatures, there is a reduction of the track geometry, as compared with environmental temperature. (Author)

High rate behavior and discharge limits in micro-pattern detectors

CERN Document Server

Bressan, A; Pagano, P; Ropelewski, Leszek; Sauli, Fabio; Biagi, S F; Buzulutskov, A F; Gruwé, M; De Lentdecker, G; Mörmann, D; Sharma, A

1999-01-01

We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strip micromegas, micro-dot, gas electron multiplier, CAT (compteur à trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8. In multiple structures, where the gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our c...

Trapping effect on the resolution of Ge(Li) detectors

International Nuclear Information System (INIS)

Venturini, L.; Suarez, A.A.

1980-01-01

This work describes the measurement of the resolution variation of a Ge(Li) detector as a function of irradiation position by a collimated gamma-ray beam. Also the resolution dependence has been measured as a function of the detector applied voltage, using collimated and non-collimated gamma-ray beam. (A.C.A.S.) [pt

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...

Neutron irradiation of RPCs for the CMS experiment

CERN Document Server

Abbrescia, M; Belli, G; Bruno, G; Colaleo, A; Guida, R; Iaselli, G; Loddo, F; Maggi, M; Marangelli, B; Natali, S; Nuzzo, S; Pugliese, G; Ranieri, A; Romano, F

2003-01-01

All the CMS muon stations will be equipped with Resistive Plate Chambers (RPCs). They will be exposed to high neutron background environment during the LHC running. In order to verify the safe operation of these detectors, an irradiation test has been carried out with two RPCs at high neutron flux (about 10**8 n cm**-**2 s**- **1), integrating values of dose and fluence equivalent to 10 LHC- years. Before and after the irradiation, the performance of the detectors was studied with cosmic muons, showing no relevant aging effects. Moreover, no indication of damage or chemical changes were observed on the electrode surfaces.

A Monte Carlo based development of a cavity theory for solid state detectors irradiated in electron beams

International Nuclear Information System (INIS)

Mobit, P.

2002-01-01

Recent Monte Carlo simulations have shown that the assumption in the small cavity theory (and the extension of the small cavity theory by Spencer-Attix) that the cavity does not perturb the electron fluence is seriously flawed. For depths beyond d max not only is there a significant difference between the energy spectra in the medium and in the solid cavity materials but there is also a significant difference in the number of low-energy electrons which cannot travel across the solid cavity and hence deposit their dose in it (i.e. stopper electrons whose residual range is less than the cavity thickness). The number of these low-energy electrons that are not able to travel across the solid state cavity increases with depth and effective thickness of the detector. This also invalidates the assumption in the small cavity theory that most of the dose deposited in a small cavity is delivered by crossers. Based on Monte Carlo simulations, a new cavity theory for solid state detectors irradiated in electron beams has been proposed as: D med (p)=D det (p) x s S-A med.det x gamma(p) e x S T , where D med (p) is the dose to the medium at point, p, D det (p) is the average detector dose to the same point, s S-A med.det is the Spencer-Attix mass collision stopping power ratio of the medium to the detector material, gamma(p) e is the electron fluence perturbation correction factor and S T is a stopper-to-crosser correction factor to correct for the dependence of the stopper-to-crosser ratio on depth and the effective cavity size. Monte Carlo simulations have been computed for all the terms in this equation. The new cavity theory has been tested against the Spencer-Attix cavity equation as the small cavity limiting case and also Monte Carlo simulations. The agreement between this new cavity theory and Monte Carlo simulations is within 0.3%. (author)

Aging tests of MSGC detectors

CERN Document Server

Boulogne, I; Defontaines, F; Grard, Fernand

2003-01-01

MSGC aging effects have been systematically studied to determine optimal performance in the design framework of the CMS forward tracker. Tests were conducted on prototypes under various operating conditions (glass substrates, Cr or Au strips, Ar-DME or Ne-DME gas mixtures, gas set-up purity, and others), using an X-ray generator for irradiation. The different steps of our investigations are summarized. They demonstrate the complexity of the aging phenomenon as well as the difficulty of getting stable behavior of MSGC detectors under high rates of irradiation.

Fast neutron detection by means of an organic solid state track detector

International Nuclear Information System (INIS)

Doerschel, B.; Streubel, G.

1980-01-01

Solid state track detectors consisting of cellulose triacetate foils are appropriate for measuring the fast neutron fluence without applying external radiators. Detector sensitivity has been determined as a function of neutron energy by performing irradiations with various neutron sources and monoenergetic neutrons of different energies. A comparison with theoretical results given in the literature for a simple model of track recording has shown sufficient agreement. The measuring errors and the influence of spectral changes in the neutron field on detector response are discussed for the studied method of fluence measurement. By means of these errors the measuring range has been determined for well defined irradiation conditions, taking into account spectral changes in the neutron field. (author)

Irradiation and beam tests qualification for ATLAS IBL Pixel Modules

International Nuclear Information System (INIS)

Rubinskiy, Igor

2013-01-01

The upgrade for the ATLAS detector will have different steps towards HL-LHC. The first upgrade for the Pixel Detector will consist in the construction of a new pixel layer which will be installed during the first shutdown of the LHC machine (foreseen for 2013–2014). The new detector, called Insertable B-Layer (IBL), will be inserted between the existing Pixel Detector and a new (smaller radius) beam-pipe at a radius of 33 mm. The IBL will require the development of several new technologies to cope with the increase in the radiation damage and the pixel occupancy and also to improve the physics performance, which will be achieved by reduction of the pixel size and of the material budget. Two different promising silicon sensor technologies (Planar n-in-n and 3D) are currently under investigation for the Pixel Detector. An overview of the sensor technologies' qualification with particular emphasis on irradiation and beam tests is presented. -- Highlights: ► The ATLAS inner tracker will be extended with a so called Insertable B-Layer (IBL). ► The IBL modules are required to withstand irradiation up to 5×10 15 n eq /cm 2 . ► Two types of silicon pixel detector technologies (Planar and 3D) were tested in beam. ► The irradiated sensor efficiency exceeds 97% both with and without magnetic field. ► The leakage current, power dissipation, module active area ratio requirements are met.

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

Recent test results on the ATLAS SCT detector

International Nuclear Information System (INIS)

Pernegger, H.

2003-01-01

The ATLAS Semiconductor Tracker (SCT) will be a central part of the tracking system of the ATLAS experiment. The SCT, which is currently under construction, will consist of four concentric barrels of silicon detectors as well as two silicon endcap detectors formed by nine disks each. After an overview of the SCT and the detector module layout, the paper will summarize recent test results obtained from silicon detector modules, which have been extensively tested before starting their large series production. The tests presented here cover electrical performance of individual modules, their performance after irradiation, as well as system tests in a multi-module setup

Design for measurement system of Doppler broadening profiles with the coincidence technique using a NaI detector in colinear geometry with the Ge detector

International Nuclear Information System (INIS)

Mori, Kazuteru; Uedono, Akira; Tanigawa, Shoichiro; Nakai, Katsuhiko

1998-01-01

The measurement system for Doppler broadening profiles with the coincidence technique using a NaI detector in colinear geometry with a Ge detector was developed. The principle of measurement system with the coincidence technique between the NaI detector and the Ge detector was described. Application of the system for the detection of vacancy-type defects introduced by electron irradiation in Czochralski-(Cz) grown Si was shown. Detail in the difference between the Doppler broadening profiles for Cz-Si and Si grown by the floating-zone method was also obtained. (author)

Design for measurement system of Doppler broadening profiles with the coincidence technique using a NaI detector in colinear geometry with the Ge detector

Energy Technology Data Exchange (ETDEWEB)

Mori, Kazuteru; Uedono, Akira; Tanigawa, Shoichiro [Tsukuba Univ., Ibaraki (Japan). Inst. of Materials Science; Nakai, Katsuhiko

1998-08-01

The measurement system for Doppler broadening profiles with the coincidence technique using a NaI detector in colinear geometry with a Ge detector was developed. The principle of measurement system with the coincidence technique between the NaI detector and the Ge detector was described. Application of the system for the detection of vacancy-type defects introduced by electron irradiation in Czochralski-(Cz) grown Si was shown. Detail in the difference between the Doppler broadening profiles for Cz-Si and Si grown by the floating-zone method was also obtained. (author)

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

CERN Document Server

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

2002-01-01

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

Precision rectifier detectors for ac resistance bridge measurements with application to temperature control systems for irradiation creep experiments

Energy Technology Data Exchange (ETDEWEB)

Duncan, M. G.

1977-05-01

The suitability of several temperature measurement schemes for an irradiation creep experiment is examined. It is found that the specimen resistance can be used to measure and control the sample temperature if compensated for resistance drift due to radiation and annealing effects. A modified Kelvin bridge is presented that allows compensation for resistance drift by periodically checking the sample resistance at a controlled ambient temperature. A new phase-insensitive method for detecting the bridge error signals is presented. The phase-insensitive detector is formed by averaging the magnitude of two bridge voltages. Although this method is substantially less sensitive to stray reactances in the bridge than conventional phase-sensitive detectors, it is sensitive to gain stability and linearity of the rectifier circuits. Accuracy limitations of rectifier circuits are examined both theoretically and experimentally in great detail. Both hand analyses and computer simulations of rectifier errors are presented. Finally, the design of a temperature control system based on sample resistance measurement is presented. The prototype is shown to control a 316 stainless steel sample to within a 0.15/sup 0/C short term (10 sec) and a 0.03/sup 0/C long term (10 min) standard deviation at temperatures between 150 and 700/sup 0/C. The phase-insensitive detector typically contributes less than 10 ppM peak resistance measurement error (0.04/sup 0/C at 700/sup 0/C for 316 stainless steel or 0.005/sup 0/C at 150/sup 0/C for zirconium).

Registration of alpha particles in Makrofol-E nuclear track detectors

Energy Technology Data Exchange (ETDEWEB)

Rammah, Y.S. [Physics Department, Faculty of Science, Menoufia University, Shebin El-Koom (Egypt); Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Physics Department, Faculty of Sciences and Arts, Najran University, P. O. Box. 11001, Najran (Saudi Arabia); Promising Centre for Sensors and Electronic Devices, Faculty of Arts and Sciences, Najran University (Saudi Arabia); Ashraf, O., E-mail: osama.ashraf@edu.asu.edu.eg [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt); Ashry, A.H. [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt)

2016-06-15

Highlights: • Makrofol-E detectors have been irradiated with alpha particles and fission fragments. • Fast detection of alpha particles in Makrofol-E detectors. • Bulk etching rate was calculated from fission track diameters. - Abstract: Fast detection of alpha particles in the range from 1 to 5 MeV in Makrofol-E polycarbonate nuclear track detectors (PCTDs) using a new chemical etchant was investigated. {sup 252}Cf and {sup 241}Am-thin open sources were used for irradiating Makrofol-E detectors with fission fragments and alpha particles in air at normal pressure and temperature (NPT). A chain of experimental work has been carried out using new etchants to register alpha particle in short time in Makrofol-E polycarbonate detectors. The etching efficiency were exhibited a clear dependence on the amount of methanol in the etching solution and etching time. The optimized chemical condition obtained at this stage of development for 200 μm Makrofol-E detectors are (8 ml of 10 N NaOH + 2 ml CH{sub 3}OH) etching solutions at 60 °C for 3 h. In this study; it is possible to observe energy detection windows for Makrofol-E detectors according to applied etching duration. Makrofol-E introduced the characteristic Bragg peak, which indicates the advantages of this detector as alpha spectrometer. Consequently, the suggested new etchant can be developed for heavy ions detection and monitoring radon levels and its daughters.

3D silicon pixel detectors for the High-Luminosity LHC

CERN Document Server

Lange, J.

2016-01-01

3D silicon pixel detectors have been investigated as radiation-hard candidates for the innermost layers of the HL-LHC upgrade of the ATLAS pixel detector. 3D detectors are already in use today in the ATLAS IBL and AFP experiments. These are based on 50x250 um2 large pixels connected to the FE-I4 readout chip. Detectors of this generation were irradiated to HL-LHC fluences and demonstrated excellent radiation hardness with operational voltages as low as 180 V and power dissipation of 12--15 mW/cm2 at a fluence of about 1e16 neq/cm2, measured at -25 degree C. Moreover, to cope with the higher occupancies expected at the HL-LHC, a first run of a new generation of 3D detectors designed for the HL-LHC was produced at CNM with small pixel sizes of 50x50 and 25x100 um2, matched to the FE-I4 chip. They demonstrated a good performance in the laboratory and in beam tests with hit efficiencies of about 97% at already 1--2V before irradiation.

Nickel Foil as Transmutation Detector for Neutron Fluence Measurements

Directory of Open Access Journals (Sweden)

Klupák Vít

2016-01-01

Full Text Available Activation detectors are very often used for determination of the neutron fluence in reactor dosimetry. However, there are few disadvantages concerning these detectors; it is the demand of the knowledge of the irradiation history and a loss of information due to a radioactive decay in time. Transmutation detectors TMD could be a solution in this case. The transmutation detectors are materials in which stable or long-lived nuclides are produced by nuclear reactions with neutrons. From a measurement of concentration of these nuclides, neutron fluence can be evaluated regardless of the cooling time.

Silicon carbide detectors for diagnostics of ion emission from laser plasmas

International Nuclear Information System (INIS)

Musumeci, Paolo; Zimbone, Massimo; Calcagno, Lucia; Cutroneo, Maria; Torrisi, Lorenzo; Velyhan, Andry

2014-01-01

Silicon carbide (SiC) detectors have been employed to analyze the multi-MeV ions generated from laser plasma. The irradiation was performed with the iodine laser of Prague Asterix Laser System Laboratory operating at 10 16  W cm −2 pulse intensity. Thin metallic and polymeric targets were irradiated and the produced plasmas were monitored in the forward direction. The use of SiC detectors ensures the cutting of the visible and soft UV radiation emitted from plasma, enhancing the sensitivity to protons and very fast heavy ions. The time-of-flight spectra obtained by irradiating polymeric films with high laser pulse energy produce protons with energy in the range 1.0–2.5 MeV and all the charge states of carbon ions. The metallic Al target allows achieving energy up to 3.0 MeV for protons and 40 MeV for Al ions. All the results reveal the high performances of these detectors in terms of resolution and response time. (paper)

High-rate irradiation of 15mm muon drift tubes and development of an ATLAS compatible readout driver for micromegas detectors

CERN Document Server

Zibell, Andre

The upcoming luminosity upgrades of the LHC accelerator at CERN demand several upgrades to the detectors of the ATLAS muon spectrometer, mainly due to the proportionally increasing rate of uncorrelated background irradiation. This concerns also the "Small Wheel" tracking stations of the ATLAS muon spectrometer, where precise muon track reconstruction will no longer be assured when around 2020 the LHC luminosity is expected to reach values 2 to 5 times the design luminosity of $1 \\times 10^{34} \\text{cm}^{-2}\\text{s}^{-1}$, and when background hit rates will exceed 10 kHz/cm$^2$. This, together with the need of an additional triggering station in this area with an angular resolution of 1 mrad, requires the construction of "New Small Wheel" detectors for a complete replacement during the long maintenance period in 2018 and 2019. As possible technology for these New Small Wheels, high-rate capable sMDT drift tubes have been investigated, based on the ATLAS 30 mm Monitored Drift Tube technology, but with a smalle...

Damage induced in semiconductors by swift heavy ion irradiation

International Nuclear Information System (INIS)

Levalois, M.; Marie, P.

1999-01-01

The behaviour of semiconductors under swift heavy ion irradiation is different from that of metals or insulators: no spectacular effect induced by the inelastic energy loss has been reported in these materials. We present here a review of irradiation effects in the usual semiconductors (silicon, germanium and gallium arsenide). The damage is investigated by means of electrical measurements. The usual mechanisms of point defect creation can account for the experimental results. Besides, some results obtained on the wide gap semiconductor silicon carbide are reported. Concerning the irradiation effects induced by heavy ions in particle detectors, based on silicon substrate, we show that the deterioration of the detector performances can be explained from the knowledge of the substrate properties which are strongly perturbed after high doses of irradiation. Finally, some future ways of investigation are proposed. The silicon substrate is a good example to compare the irradiation effects with different particles such as electrons, neutrons and heavy ions. It is then necessary to use parameters which account for the local energy deposition, in order to describe the damage in the material

Effect of trapping of charge carriers on the resolution of Ge(Li) detectors; Influencia da captura de portadores de cargas sobre a resolucao em detectores Ge(Li)

Energy Technology Data Exchange (ETDEWEB)

Venturini, Luzia

1979-07-01

In this work a measurement is described of the variation of the resolution of a Ge(Li) detector as a function of the position of irradiation of a collimated gamma-ray beam. Also the variation of the resolution has been measured as a function of the applied detector voltage, using a collimated and a non-collimated gamma-ray beam. The measurement indicate that in the process of charge collection loss of holes predominates and the best resolution is obtained in the middle of the compensated region. It has been verified that, in the case of a collimated gamma beam the detector resolution improves with increasing detector bias up to at least 5100 Volts. For a non-collimated gamma beam, however, the resolution reaches a constant value at about 4400 Volts. The dependence of resolution on the position of irradiation can be accounted for by introducing a local ionization factor different from the usual position independent Fano factor. (author)

Infrared LED Array For Silicon Strip Detector Qualification

CERN Document Server

Dirkes, Guido; Hartmann, Frank; Heier, Stefan; Schwerdtfeger, Wolfgang; Waldschmitt, M; Weiler, K W; Weseler, Siegfried

2003-01-01

The enormous amount of silicon strip detector modules for the CMS tracker requires a test-sytem to allow qualification of each individual detector module and its front-end electronics within minutes. The objective is to test the detector with a physical signal. Signals are generated in the detector by illumination with lightpulses emitted by a LED at 950~nm and with a rise time of 10~ns. In order to avoid a detector moving, an array of 64 LEDs is used, overlaping the complete detector width. The total length of an array is 15~cm. The spot size of an individual LED is controlled by apertures to illuminate about 25 strips. Furthermore it is possible to simulate the high leakage current of irradiated sensors by constant illumination of the sensor. This provides an effective mean to identfy pinholes on a sensor.

Proton irradiation of a swept charge device at cryogenic temperature and the subsequent annealing

International Nuclear Information System (INIS)

Gow, J P D; Smith, P H; Hall, D J; Holland, A D; Murray, N J; Pool, P

2015-01-01

A number of studies have demonstrated that a room temperature proton irradiation may not be sufficient to provide an accurate estimation of the impact of the space radiation environment on detector performance. This is a result of the relationship between defect mobility and temperature, causing the performance to vary subject to the temperature history of the device from the point at which it was irradiated. Results measured using Charge Coupled Devices (CCD) irradiated at room temperature therefore tend to differ from those taken when the device was irradiated at a cryogenic temperature, more appropriate considering the operating conditions in space, impacting the prediction of in-flight performance. This paper describes the cryogenic irradiation, and subsequent annealing of an e2v technologies Swept Charge Device (SCD) CCD236 irradiated at −35.4°C with a 10 MeV equivalent proton fluence of 5.0 × 10 8 protons · cm −2 . The CCD236 is a large area (4.4 cm 2 ) X-ray detector that will be flown on-board the Chandrayaan-2 and Hard X-ray Modulation Telescope spacecraft, in the Chandrayaan-2 Large Area Soft X-ray Spectrometer and the Soft X-ray Detector respectively. The SCD is readout continually in order to benefit from intrinsic dither mode clocking, leading to suppression of the surface component of the dark current and allowing the detector to be operated at warmer temperatures than a conventional CCD. The SCD is therefore an excellent choice to test and demonstrate the variation in the impact of irradiation at cryogenic temperatures in comparison to a more typical room temperature irradiation

Neutron irradiation of RPCs for the CMS experiment

Energy Technology Data Exchange (ETDEWEB)

Abbrescia, M.; Colaleo, A.; Iaselli, G.; Loddo, F.; Maggi, M.; Marangelli, B.; Natali, S.; Nuzzo, S.; Pugliese, G. E-mail: gabriella.pugliese@ba.infn.it; Ranieri, A.; Romano, F.; Altieri, S.; Belli, G.; Bruno, G.; Guida, R.; Ratti, S.P.; Riccardi, C.; Torre, P.; Vitulo, P

2003-08-01

All the CMS muon stations will be equipped with Resistive Plate Chambers (RPCs). They will be exposed to high neutron background environment during the LHC running. In order to verify the safe operation of these detectors, an irradiation test has been carried out with two RPCs at high neutron flux (about 10{sup 8} n cm{sup -2} s{sup -1}), integrating values of dose and fluence equivalent to 10 LHC-years. Before and after the irradiation, the performance of the detectors was studied with cosmic muons, showing no relevant aging effects. Moreover, no indication of damage or chemical changes were observed on the electrode surfaces.

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.

Multilayer detector for skin absorbed dose measuring

International Nuclear Information System (INIS)

Osanov, D.P.; Panova, V.P.; Shaks, A.I.

1985-01-01

A method for skin dosimetry based on utilization of multilayer detectors and permitting to estimate distribution of absorbed dose by skin depth is described. The detector represents a set of thin sensitive elements separated by tissue-equivalent absorbers. Quantitative evaluation and forecasting the degree of radiation injury of skin are determined by the formula based on determination of the probability of the fact that cells are not destroyed and they can divide further on. The given method ensures a possibility of quantitative evaluation of radiobiological effect and forecasting clinical consequences of skin irradiation by results of corresponding measurements of dose by means of the miultilayer detector

Nuclear radiation detectors using high resistivity neutron transmutation doped silicon

International Nuclear Information System (INIS)

Gessner, T.; Irmer, K.

1983-01-01

A method for the production of semiconductor detectors based on high resistivity n-type silicon is described. The n-type silicon is produced by neutron irradiation of p-type silicon. The detectors are produced by planar technique. They are suitable for the spectrometry of alpha particles and for the pulse count measurement of beta particles at room temperature. (author)

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.

The Life Span of the BD-PND Bubble Detector

International Nuclear Information System (INIS)

Vanhavere, F.; Loos, M.; Thierens, H.

1999-01-01

BD-PND bubble detectors from Bubble Technology Industries (BTI) were used to conduct a study of the life span of these detectors. The manufacturer guarantees an optimum detector performance for three months after receipt. Nevertheless, it is important to know the evolution of their characteristics with time, also after those three months. On a standard set-up with a 252 Cf source the bubble detectors were irradiated until they reached the end of their life span. During this period, the evolution in sensitivity was monitored. The temperature compensating system seems to be the limiting factor with time for the use of the BTI bubble detectors. The change in temperature dependence with age was determined. The same parameters were also checked with several batches of detectors that were used in practice. (author)

Critical angles for fission fragment registrations in some solid state track detectors

Energy Technology Data Exchange (ETDEWEB)

Belyaev, A D; Bahromi, I I; Beresina, N V [AN Uzbekskoj SSR, Tashkent. Inst. Yadernoj Fiziki; and others

1980-03-01

In studies of the registration efficiency of various solid state track detectors (polycarbonate, polyethyleneterephthalate, cellulose nitrate and muscovite) the detectors were irradiated with spontaneous fission fragments from /sup 252/Cf and with fission fragments from /sup 235/U separated according to mass and energy. Experimental details are given. Critical angles for the registration of fission fragments in the various detectors are given for specified energies and masses.

Cryogenic Semiconductor Detectors: Simulation of Signal Formation & Irradiation Beam Test

CERN Document Server

AUTHOR|(CDS)2091318; Stamoulis, G; Vavougios, D

The Beam Loss Monitoring system of the Large Hadron Collider is responsible for the pro- tection of the machine from damage and for the prevention of a magnet quench. Near the interaction points of the LHC, in the triplet magnets area, the BLMs are sensitive to the collision debris, limiting their ability to distinguish beam loss signal from signal caused due to the collision products. Placing silicon & diamond detectors inside the cold mass of the mag- nets, in liquid helium temperatures, would provide significant improvement to the precision of the measurement of the energy deposition in the superconducting coil of the magnet. To further study the signal formation and the shape of the transient current pulses of the aforementioned detectors in cryogenic temperatures, a simulation application has been developed. The application provides a fast way of determining the electric field components inside the detectors bulk and then introduces an initial charge distribution based on the properties of the radiat...

Spent-fuel characterization with small CZT detectors

Energy Technology Data Exchange (ETDEWEB)

Berndt, R. [European Commission, Joint Research Centre, Ispra, 21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: Reinhard.Berndt@jrc.it; Mortreau, P. [European Commission, Joint Research Centre, Ispra, 21020 Ispra (Va) (Italy)

2006-08-01

CdTe detectors may be utilised as miniature instruments for the measurement of gamma spectra in safeguards applications [R. Arlt, V. Gryshchuk, P. Sumah, Nucl. Instr. and Meth. A 428 (1999) 127]. This is applicable for measurements both to fresh fuel and irradiated nuclear fuel. The spectrum analysis, however, is more complicated than with Ge detectors. Some reasons are: the peaks are asymmetric, the peak/Compton ratio is low, peak parameters depend on the count rate and on the properties of individual detector crystals. We developed a spectrum-unfolding code for spectra obtained with CdTe detectors. The code makes use of a series of pattern spectra of the individual instrument. It is applied to fission-product spectra and allows the coarse characterisation of the spent fuel in safeguards inspections.

Spent-fuel characterization with small CZT detectors

International Nuclear Information System (INIS)

Berndt, R.; Mortreau, P.

2006-01-01

CdTe detectors may be utilised as miniature instruments for the measurement of gamma spectra in safeguards applications [R. Arlt, V. Gryshchuk, P. Sumah, Nucl. Instr. and Meth. A 428 (1999) 127]. This is applicable for measurements both to fresh fuel and irradiated nuclear fuel. The spectrum analysis, however, is more complicated than with Ge detectors. Some reasons are: the peaks are asymmetric, the peak/Compton ratio is low, peak parameters depend on the count rate and on the properties of individual detector crystals. We developed a spectrum-unfolding code for spectra obtained with CdTe detectors. The code makes use of a series of pattern spectra of the individual instrument. It is applied to fission-product spectra and allows the coarse characterisation of the spent fuel in safeguards inspections

Research on the measurement of the ultraviolet irradiance in the xenon lamp aging test chamber

Science.gov (United States)

Ji, Muyao; Li, Tiecheng; Lin, Fangsheng; Yin, Dejin; Cheng, Weihai; Huang, Biyong; Lai, Lei; Xia, Ming

2018-01-01

This paper briefly introduces the methods of calibrating the irradiance in the Xenon lamp aging test chamber. And the irradiance under ultraviolet region is mainly researched. Three different detectors whose response wave range are respectively UVA (320 400nm), UVB (275 330nm) and UVA+B (280 400nm) are used in the experiment. Through comparing the measuring results with different detectors under the same xenon lamp source, we discuss the difference between UVA, UVB and UVA+B on the basis of the spectrum of the xenon lamp and the response curve of the detectors. We also point out the possible error source, when use these detectors to calibrate the chamber.

Performance of n-in-p pixel detectors irradiated at fluences up to $5x10^{15} n_{eq}/cm^{2}$ for the future ATLAS upgrades

CERN Document Server

INSPIRE-00219560; La Rosa, A.; Nisius, R.; Pernegger, H.; Richter, R.H.; Weigell, P.

We present the results of the characterization of novel n-in-p planar pixel detectors, designed for the future upgrades of the ATLAS pixel system. N-in-p silicon devices are a promising candidate to replace the n-in-n sensors thanks to their radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed with the ATLAS pixel read-out systems, TurboDAQ and USBPIX, before and after irradiation with 25 MeV protons and neutrons up to a fluence of 5x10**15 neq /cm2. The charge collection measurements carried out with radioactive sources have proven the feasibility of employing this kind of detectors up to these particle fluences. The collected charge has been measured to be for any fluence in excess of twice the value of the FE-I3 threshold, tuned to 3200 e. The first result...

Radiation hardness of thin Low Gain Avalanche Detectors

Science.gov (United States)

Kramberger, G.; Carulla, M.; Cavallaro, E.; Cindro, V.; Flores, D.; Galloway, Z.; Grinstein, S.; Hidalgo, S.; Fadeyev, V.; Lange, J.; Mandić, I.; Medin, G.; Merlos, A.; McKinney-Martinez, F.; Mikuž, M.; Quirion, D.; Pellegrini, G.; Petek, M.; Sadrozinski, H. F.-W.; Seiden, A.; Zavrtanik, M.

2018-05-01

Low Gain Avalanche Detectors (LGAD) are based on a n++-p+-p-p++ structure where an appropriate doping of the multiplication layer (p+) leads to high enough electric fields for impact ionization. Gain factors of few tens in charge significantly improve the resolution of timing measurements, particularly for thin detectors, where the timing performance was shown to be limited by Landau fluctuations. The main obstacle for their operation is the decrease of gain with irradiation, attributed to effective acceptor removal in the gain layer. Sets of thin sensors were produced by two different producers on different substrates, with different gain layer doping profiles and thicknesses (45, 50 and 80 μm). Their performance in terms of gain/collected charge and leakage current was compared before and after irradiation with neutrons and pions up to the equivalent fluences of 5 ṡ 1015 cm-2. Transient Current Technique and charge collection measurements with LHC speed electronics were employed to characterize the detectors. The thin LGAD sensors were shown to perform much better than sensors of standard thickness (∼300 μm) and offer larger charge collection with respect to detectors without gain layer for fluences gain prolongs the beneficial performance of LGADs. Pions were found to be more damaging than neutrons at the same equivalent fluence, while no significant difference was found between different producers. At very high fluences and bias voltages the gain appears due to deep acceptors in the bulk, hence also in thin standard detectors.

Fast and high-energy neutron detection with nuclear track detectors: Results of the European joint experiments 1992/93

Energy Technology Data Exchange (ETDEWEB)

Schraube, H. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany); Alberts, W.G. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Weeks, A.R. [comps.] [Nuclear Electric plc, Berkeley (United Kingdom). Berkeley Technology Centre

1997-12-31

Under the auspices of EURADOS, the European radiation dosimetry group, seventeen recognised laboratories engaged in the field of individual neutron dosimetry with passive track detectors participated in an international comparative experiment. A number of twenty-seven detector systems, predominantly etched track detectors with the material PADC (poly allyl diglycol carbonate), were employed by the participating laboratories. Quasi-monoenergetic neutrons were provided for irradiations free-in-air and on front of a PMMA phantom by the GSF (Forschungszentrum fuer Umwelt und Gesundheit, Neuherberg, Germany) and by the PTB (Physikalisch-Technische Bundesanstalt, Braunschweig, Germany). High energy irradiations were conducted by the PSI (Paul-Scherrer Institut, Villigen, Switzerland). The results of the on-phantom irradiations were used to derive energy and angular responses of the track detectors, those of the free-in-air irradiations to obtain data for the linearity characteristics of the response with dose. The report contains a short description and the original data of the participating laboratories, displays the irradiation and reference conditions, and provides an over-all evaluation. Emphasis is placed on the quantitative evaluation of the background characteristics and of the non-linearity observed with most of the systems employed which limits their useful dose-range of application. (orig.)

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.

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)

Rad-hard electronics study for SSC detectors

International Nuclear Information System (INIS)

Ekenberg, T.; Dawson, J.; Stevens, A.; Haberichter, W.

1991-01-01

The radiation environment in a SSC detector operating at a luminosity of 10 33 cm -2 s -1 will put stringent requirements on radiation hardness of the electronics. Over the expected 10 year life-time of a large detector, ionizing radiation doses of up to 20 MRad and neutron fluences of 10 16 neutrons/cm 2 are projected. At a luminosity of 10 34 cm -2 s -1 even higher total doses are expected. the effect of this environment have been simulated by exposing CMOS/bulk and CMOS/SOS devices from monolithic processes to neutrons and ionizing radiation. leakage currents, noise variations, and DC characteristics have been measured before and after exposure in order to evaluate the effects of the irradiations. As expected the device characteristics remained virtually unchanged by neutron irradiation, while ionizing radiation caused moderate degradation of performance. 5 refs., 6 figs

Operation of Silicon, Diamond and liquid Helium Detectors in the range of Room Temperature to 1.9 K and after an Irradiation Dose of several Mega Gray

CERN Document Server

Kurfuerst, C; Dehning, B; Eisel, T; Sapinski, M; Eremin, V

2013-01-01

At the triplet magnets, close to the interaction regions of the Large Hadron Collider (LHC), the current Beam Loss Monitoring (BLM) system is sensitive to the debris from the collision points. For future beams, with higher energy and intensity the expected increase in luminosity implicate an increase of the debris from interaction products covering the quench-provoking beam losses from the primary proton beams. The investigated option is to locate the detectors as close as possible to the superconducting coil, where the signal ratio of both is optimal. Therefore the detectors have to be located inside the cold mass of the superconducting magnets in superfluid helium at 1.9 Kelvin. Past measurements have shown that a liquid helium ionisation chamber, diamond and silicon detectors are promising candidates for cryogenic beam loss monitors. The carrier parameter, drift velocity, and the leakage current changes will be shown as a function of temperature. New high irradiation test beam measurements at room temperat...

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

A comparative study of the Si diodes of N type applied to high-dose range dosimetry

International Nuclear Information System (INIS)

Pascoalino, Kelly Cristina da Silva; Goncalves, Josemary Angelica Correa; Tobias, Carmen Cecilia Bueno

2011-01-01

This work presents the results of the comparative studies of floating-zone (Fz) and magnetic Czochralski (MCz) n-type silicon diodes as gamma dosimeters. The devices were irradiated with gamma rays from 60 Co source, Gammacell 220, at Radiation Technology Center (CTR-IPEN/CNEN-SP) with the dose rate of 2 kGy/h. The results with total absorbed doses of approximately 1 MGy showed that the devices studied are tolerant to radiation damages and then can be used as an online dosimeter in high doses radiation processing. (author)

A detector for use in high energy bremsstrahlung shielding studies

International Nuclear Information System (INIS)

Wilson, O.J.; Thomson, J.E.M.

1983-01-01

The design, development and calibration of a detector based on the principle of the Moxon-Rae detector is discussed. It is ideally suited to the measurement of the energy fluence of photons transmitted through a thick shield which has been irradiated with high energy bremsstrahlung. The detection sensitivity is 10 4 to 10 5 times that of the P2 ion chamber

Utilization of plastic detector for pool water radioactivity control of IEA-R1 reactor. Examination of fuel element irradiation behaviour fabricated at IPEN/CNEN-SP

International Nuclear Information System (INIS)

Berretta, J.R.; Mesquita, C.H. de; Madi Filho, T.

1989-01-01

For the examination of fuel element irradiation behavior that were fabricated at IPEN/CNEN/SP Metalurgical Departament, it was provided a detection system for pool water radioactivity measurements. This system uses a plastic scintillator detector produced at IPEN/CNEN-SP Health Physics Department, with dimensions and shape apropriated for such work. The detection system shows a sensibility of 4.125x10 -2 dps/cm 3 and 20% of efficiency for 131 I radiations. (author) [pt

Simulation of new p-type strip detectors with trench to enhance the charge multiplication effect in the n-type electrodes

International Nuclear Information System (INIS)

Fernández-Martínez, P.; Pellegrini, G.; Balbuena, J.P.; Quirion, D.; Hidalgo, S.; Flores, D.; Lozano, M.; Casse, G.

2011-01-01

This paper shows the simulation results of new p-type strip detectors with trench electrodes to enhance the charge multiplication effect in the irradiated detector. The new design includes baby microstrip detectors (area=1 cm 2 ) with a strip pitch of 80 μm and p-stop isolation structures. The strip has a 5 μm-wide trench along all its length, filled and doped with polysilicon to create a deep N + contact into the material bulk. The trench depth can be varied in order to study the influence of the electric field on the charge multiplication effect in heavily irradiated samples. Some alternative designs have also been studied to establish a comparison between various structures using different technologies. Simulation reproduce the electrical behaviour under different irradiation conditions, taking into account the damage accumulated after irradiation with neutrons and protons with several fluence values. The investigation of these effects provides important indications on the ability of this modified electrode geometry to control and optimise the charge multiplication effect, in order to fully recover the collection efficiency of heavily irradiated microstrip detectors, at reasonable bias voltage compatible with the voltage feed limitation of the CERN SLHC experiments.

The radiation field in the New Gamma Irradiation Facility GIF++ at CERN

CERN Document Server

Pfeiffer, Dorothea

2017-09-11

The high-luminosity LHC (HL-LHC) upgrade is setting now a new challenge for particle detector technologies. The increase in luminosity will produce a particle background in the gas-based muon detectors that is ten times higher than under conditions at the LHC. The detailed knowledge of the detector performance in the presence of such a high background is crucial for an optimized design and efficient operation after the HL-LHC upgrade. A precise understanding of possible aging effects of detector materials and gases is of extreme importance. To cope with these challenging requirements, a new Gamma Irradiation Facility (GIF++) was designed and built at the CERN SPS North Area as successor of the Gamma Irradiation Facility (GIF) during the Long Shutdown 1 (LS1) period. It features an intense source of 662 keV photons with adjustable intensity, to simulate continuous background over large areas, and, combined with a high energy muon beam, to measure detector performance in the presence of the background. The new ...

Thermal Properties of the Silicon Microstrip Endcap Detector

CERN Document Server

Feld, Lutz; Hammarström, R

1998-01-01

Irradiated silicon detectors must be cooled in order to guarantee stable short and long term operation. Using the SiF1 milestone prototype we have performed a detailed analysis of the thermal properties of the silicon microstrip endcap detector. The strongest constraint on the cooling system is shown to be set by the need to avoid thermal runaway of the silicon detectors. We show that, taking into account the radiation damage to the silicon after 10 years of LHC operation and including some safety margin, the detector will need a cooling fluid temperature of around -20 C. The highest temperature on the silicon will then be in the range -15 C to -10 C. This sets an upper limit on the ambient temperature in the tracker volume.

Solid state nuclear track detectors kit for the use in teaching

International Nuclear Information System (INIS)

Khouri, M.T.F.C.; Koskinas, M.F.

1988-11-01

The kit intends to improve the possibilities in performing experiments of Nuclear Physics in Modern Physics laboratories of Physics Course introducing the solid state nuclear track detectors. In these materials the passage of heavily ionizing nuclear particles creates paths (tracks) that may be revealed and made visible in an optical microscope. By the help of the kit several experiments and/or demonstrations may be performed. The kit contains solid state nuclear track detectors unirradiated and irradiated, irradiated etched and unetched sheets: an alpha source of 241 Am and an instrution text with photomicrographs. To use the kit the laboratory must have an ordinary optical microscope. (author) [pt

NEUTRON SPECTRUM MEASUREMENTS USING MULTIPLE THRESHOLD DETECTORS

Energy Technology Data Exchange (ETDEWEB)

Gerken, William W.; Duffey, Dick

1963-11-15

From American Nuclear Society Meeting, New York, Nov. 1963. The use of threshold detectors, which simultaneously undergo reactions with thermal neutrons and two or more fast neutron threshold reactions, was applied to measurements of the neutron spectrum in a reactor. A number of different materials were irradiated to determine the most practical ones for use as multiple threshold detectors. These results, as well as counting techniques and corrections, are presented. Some materials used include aluminum, alloys of Al -Ni, aluminum-- nickel oxides, and magesium orthophosphates. (auth)

Modifications in track registration response of PADC detector by energetic protons

CERN Document Server

Dwivedi, K K; Fink, D; Mishra, R; Tripathy, S P; Kulshreshtha, A; Khathing, D T

1999-01-01

It has been well established that different ionising radiations modify the track registration properties of dielectric solids. In an effort to study the response of Polyallyl diglycol carbonate (PADC Homalite) detector towards fission fragment, PADC detectors were exposed to 10 sup 4 Gy dose of 62 MeV protons and then one set of samples were exposed to fission fragments from a sup 2 sup 5 sup 2 Cf source. Two of these detectors were containing a thin layer of Buckminsterfullerene (C sub 6 sub 0). The study of the etched tracks by Leitz Optical Microscope reveals that the track diameters are enhanced by more than 70% in the proton irradiated zone as compared to that in the unirradiated zone. Scanning Electron Microscopy was performed after etching the sample in 6 N NaOH at 55 deg. C for different etching times, to study the details of the surface modifications due to proton irradiation of PADC detectors with and without C sub 6 sub 0 layer. Our observations revealed that the diameters and density of proton tra...

High-resolution ion-implanted silicon detectors

International Nuclear Information System (INIS)

von Borany, J.; Schmidt, B.

1985-01-01

An account is given of the properties of silicon detectors developed at the Central Institute of Nuclear Research of the Academy of Sciences of the German Democratic Republic (Rossendorf) and made by a special planar technology using ion implantation, anodic oxidation, thermal oxidation in an oxygen atmosphere containing HCl, and annealing by pulses of 10--20 msec duration. The resolution for α particles of 5.5 MeV energy was 11.2 keV (active area A 2 ). The detectors were characterized by a low intrinsic noise (< or =5 keV), so that they could be used for spectrometry of low-energy electrons (E/sub e/< or =250 keV). In a certain range of energies (E/sub x/ = 15--60 keV) it was possible to use these detectors for spectrometry of x rays at room temperature. Examples and results of applications of detectors in radiation chemistry (investigations of backscattering of particles and nuclear reaction spectroscopy) are given. The feasibility of annealing of radiation defects in such detectors after irradiation with a large dose of charged particles is considered

Measuring device for the distribution of burn-up degree in fuel assembly irradiated in nuclear reactor

International Nuclear Information System (INIS)

Kumanomido, Hironori

1989-01-01

The object of the invention is to measure the distribution of burn-up degree, of fuel assemblies irradiated in a nuclear reactor in a short time and exactly. That is, the device comprises a device main body having substantially the same length as that for the axial length of a fuel assembly and a detector container disposed axially slidably to the main body. A plurality of radiation detectors are arranged at an equi-axial pitch and contained in the container. The container is caused to slide at a pitch equal to the equi-axial distance of the detectors. In the device having thus been constituted, measurement is conducted at least for twice at an axial position on the side of a fuel assembly irradiated in the nuclear reactor and a position caused to slide therefrom by one pitch. Based on the result, the sensitivities between each of the detectors are compared and the relative sensitivity of the radiation detectors is calibrated. Accordingly, the sensitivity between each of the detectors can be calibrated rapidly and easily. As a result, the distribution of the burn-up degree, etc of irradiated fuel assembly can be measured exactly. (K.M.)

Analysis of reactive aldehydes formed from the irradiated skin lipid, triolein

International Nuclear Information System (INIS)

Niyati-Shirkhodaee, F.; Shibamoto. Y.

1992-01-01

One of the major skin lipids, triolein, was irradiated by 300 nm uv light under conditions approximately those at the skin surface exposed to sunlight for different periods of time. Irradiated samples were analyzed for acrolein, formaldehyde, and acetaldehyde by gas chromatography. Acrolein formed was derivatized to more stable 1-methyl-2-pyrazoline with N-methylhydrazine and analyzed by a nitrogen-phosphorus specific detector. Formaldehyde and acetaldehyde formed were reacted with cysteamine to give thiazolidine and 2-methylthiazolidine, respectively and analyzed by a flame photometric sulfur specific detector. The maximum amount of acrolein (1.05 nmol/mg triolein) was formed after 6 hr irradiation. The maximum quantities of formaldehyde (6 nmol/mg triolein) and acetaldehyde (2.71 nmol/mg triolein) were formed after 12 hr irradiation. Both formaldehyde and acrolein have been known to cause skin irritation in the levels of 1 ppM

High rate behavior and discharge limits in micro-pattern detectors

International Nuclear Information System (INIS)

Bressan, A.; Hoch, M.; Pagano, P.; Ropelewski, L.; Sauli, F.; Biagi, S.; Buzulutskov, A.; Gruwe, M.; De Lentdecker, G.; Moermann, D.; Sharma, A.

1999-01-01

We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strips, micromegas, micro-dot, gas electron multiplier, CAT (compteur a trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8 . In multiple structures, where the gain is shared between two devices in cascade, the maximum overall gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our conclusion is that only multiple devices can guarantee a sufficient margin of reliability for operation in harsh LHC running conditions

Dosimetric characterization of a commercial two-dimensional array detector; Caracterizacao dosimetrica de um detector matricial bidimensional comercial

Energy Technology Data Exchange (ETDEWEB)

Gialluisi, Bruno L.; Santos, Gabriela R. dos; Sales, Camila P. de; Resende, Guilherme R.A.; Habitzreuter, Angela B.; Rodrigues, Laura N., E-mail: brunogialluisi@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

2013-04-15

This paper investigates the dosimetric characteristics and performance of an array detector commercially available. The device is the I'mRT MatriXX® which is a two-dimensional detector array used in the verification of complex radiotherapy plans. It consists of 1,020 parallel plate ion chamber arranged in a 32x32 grid. Dose linearity was studied and its response was linear within the range of 5 to 1000 MU (R{sup 2} = 1). Dose rate dependence showed a maximum deviation of 0,62% comparatively with readings to 320 cGy/min. The detector stability was verified through repeated irradiations. Output factors matched well with measurements made with a Farmer chamber with an average deviation of 1,54%. The detector's effective point of measurement was determined and the inverse square law was also verified with a percentage deviation smaller than 3%. The results show that this detector can be used for quality control in IMRT thus reducing the time spent in the dosimetric verification of radiation fields. (author)

Dosimetric characterization of a commercial two-dimensional array detector; Caracterizacao dosimetrica de um detector matricial bidimensional comercial

Energy Technology Data Exchange (ETDEWEB)

Gialluisi, Bruno L.; Santos, Gabriela R. dos; Sales, Camila P. de; Resende, Guilherme R.A.; Habitzreuter, Angela B.; Rodrigues, Laura N., E-mail: brunogialluisi@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

2013-04-15

This paper investigates the dosimetric characteristics and performance of an array detector commercially available. The device is the I'mRT MatriXX® which is a two-dimensional detector array used in the verification of complex radiotherapy plans. It consists of 1,020 parallel plate ion chamber arranged in a 32x32 grid. Dose linearity was studied and its response was linear within the range of 5 to 1000 MU (R{sup 2} = 1). Dose rate dependence showed a maximum deviation of 0,62% comparatively with readings to 320 cGy/min. The detector stability was verified through repeated irradiations. Output factors matched well with measurements made with a Farmer chamber with an average deviation of 1,54%. The detector's effective point of measurement was determined and the inverse square law was also verified with a percentage deviation smaller than 3%. The results show that this detector can be used for quality control in IMRT thus reducing the time spent in the dosimetric verification of radiation fields. (author)

Technology developments and first measurements of Low Gain Avalanche Detectors (LGAD) for high energy physics applications

International Nuclear Information System (INIS)

Pellegrini, G.; Fernández-Martínez, P.; Baselga, M.; Fleta, C.; Flores, D.; Greco, V; Hidalgo, S.; Mandić, I.; Kramberger, G.; Quirion, D.; Ullan, M.

2014-01-01

This paper introduces a new concept of silicon radiation detector with intrinsic multiplication of the charge, called Low Gain Avalanche Detector (LGAD). These new devices are based on the standard Avalanche Photo Diodes (APD) normally used for optical and X-ray detection applications. The main differences to standard APD detectors are the low gain requested to detect high energy charged particles, and the possibility to have fine segmentation pitches: this allows fabrication of microstrip or pixel devices which do not suffer from the limitations normally found [1] in avalanche detectors. In addition, a moderate multiplication value will allow the fabrication of thinner devices with the same output signal of standard thick substrates. The investigation of these detectors provides important indications on the ability of such modified electrode geometry to control and optimize the charge multiplication effect, in order to fully recover the collection efficiency of heavily irradiated silicon detectors, at reasonable bias voltage, compatible with the voltage feed limitation of the CERN High Luminosity Large Hadron Collider (HL-LHC) experiments [2]. For instance, the inner most pixel detector layers of the ATLAS tracker will be exposed to fluences up to 2×10 16 1 MeV n eq /cm 2 , while for the inner strip detector region fluences of 1×10 15 n eq /cm 2 are expected. The gain implemented in the non-irradiated devices must retain some effect also after irradiation, with a higher multiplication factor with respect to standard structures, in order to be used in harsh environments such those expected at collider experiments

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).

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)

Effect of trapping of charge carriers on the resolution of Ge(Li) detectors

International Nuclear Information System (INIS)

Venturini, Luzia

1979-01-01

In this work a measurement is described of the variation of the resolution of a Ge(Li) detector as a function of the position of irradiation of a collimated gamma-ray beam. Also the variation of the resolution has been measured as a function of the applied detector voltage, using a collimated and a non-collimated gamma-ray beam. The measurement indicate that in the process of charge collection loss of holes predominates and the best resolution is obtained in the middle of the compensated region. It has been verified that, in the case of a collimated gamma beam the detector resolution improves with increasing detector bias up to at least 5100 Volts. For a non-collimated gamma beam, however, the resolution reaches a constant value at about 4400 Volts. The dependence of resolution on the position of irradiation can be accounted for by introducing a local ionization factor different from the usual position independent Fano factor. (author)

Spallation products induced by energetic neutrons in plastic detector material

CERN Document Server

Grabisch, K; Enge, W; Scherzer, R

1977-01-01

Cellulose nitrate plastic detector sheets were irradiated with secondary neutrons of the 22 GeV/c proton beam at the CERN accelerator. He, Li and Be particles which are produced in nuclear interactions of the neutrons with the target elements C, N and O of the plastic detector material are measured. Preliminary angle and range distributions and isotropic abundances of the secondary particles are discussed. (6 refs).

In situ radiation test of silicon and diamond detectors operating in superfluid helium and developed for beam loss monitoring

Energy Technology Data Exchange (ETDEWEB)

Kurfürst, C.; Dehning, B.; Sapinski, M.; Bartosik, M.R.; Eisel, T.; Fabjan, C.; Rementeria, C.A. [CERN, Geneva (Switzerland); Griesmayer, E. [CIVIDEC Instrumentation, GmbH, Vienna (Austria); Eremin, V. [Ioffe Institute, St. Petersburg (Russian Federation); Verbitskaya, E., E-mail: elena.verbitskaya@cern.ch [Ioffe Institute, St. Petersburg (Russian Federation); Zabrodskii, A.; Fadeeva, N.; Tuboltsev, Y.; Eremin, I. [Ioffe Institute, St. Petersburg (Russian Federation); Egorov, N. [Research Institute of Material Science and Technology, Zelenograd, Moscow (Russian Federation); Härkönen, J.; Luukka, P.; Tuominen, E. [Helsinki Institute of Physics, Helsinki (Finland)

2015-05-11

As a result of the foreseen increase in the luminosity of the Large Hadron Collider, the discrimination between the collision products and possible magnet quench-provoking beam losses of the primary proton beams is becoming more critical for safe accelerator operation. We report the results of ongoing research efforts targeting the upgrading of the monitoring system by exploiting Beam Loss Monitor detectors based on semiconductors located as close as possible to the superconducting coils of the triplet magnets. In practice, this means that the detectors will have to be immersed in superfluid helium inside the cold mass and operate at 1.9 K. Additionally, the monitoring system is expected to survive 20 years of LHC operation, resulting in an estimated radiation fluence of 1×10{sup 16} proton/cm{sup 2}, which corresponds to a dose of about 2 MGy. In this study, we monitored the signal degradation during the in situ irradiation when silicon and single-crystal diamond detectors were situated in the liquid/superfluid helium and the dependences of the collected charge on fluence and bias voltage were obtained. It is shown that diamond and silicon detectors can operate at 1.9 K after 1×10{sup 16} p/cm{sup 2} irradiation required for application as BLMs, while the rate of the signal degradation was larger in silicon detectors than in the diamond ones. For Si detectors this rate was controlled mainly by the operational mode, being larger at forward bias voltage. - Highlights: • Silicon and diamond detectors are proposed for beam loss monitoring at LHC. • The first in situ radiation test of Si and diamond detectors at 1.9 K is described. • Both diamond and silicon detectors survived after 1×10{sup 16} p/cm{sup 2} irradiation at 1.9 K. • The rate of Si detectors degradation depends on bias polarity and is larger at V{sub forw}. • Sensitivity of Si detectors irradiated to 1×10{sup 16} p/cm{sup 2} is independent on resistivity.

Detection of irradiated foods with the photo-stimulated luminescence technique. Selection of a glass fiber filter for evaluating the performance of the PSL detectors

International Nuclear Information System (INIS)

Sekiguchi, Masayuki; Yamazaki, Masao; Goto, Michiko

2008-01-01

The PSL method is useful as a screening technique of irradiated foods to support efficient uses of TL analysis. Recently, there has been the growing need for the system check or calibration using the standard materials with spread of domestically -produced PSL detector. In this research, we characterized the PSL of several types of glass fiber filters and compared the cumulate photon counts of a selected filter of them (GA-100) with those of the SUERC paprika standard for PSL measurements. GA-100 filter showed a linear relationship between cumulate photon counts and irradiation doses, and the cumulate photon counts in the first 2 months after gamma rays irradiation (261Gy) were markedly decreased and reduced to about 5000 counts (the upper threshold of PSL) after 4 months. However, further long-term storage and dose increase was necessary to produce the filter with more adequate PSI property as a standard material. Light exposure (630Lux) within 3 minutes to GA-100 had little effect on the cumulate photon counts. GA-100 showed relatively less variation in cumulate photon counts compared with the paprika standard in a series of studies. (author)

Development of irradiation rig in HTTR and dosimetry method. I-I type irradiation equipment

Energy Technology Data Exchange (ETDEWEB)

Shibata, Taiju; Kikuchi, Takayuki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Miyamoto, Satoshi; Ogura, Kazutomo [Japan Atomic Power Co., Tokyo (Japan)

2002-12-01

The High Temperature Engineering Test Reactor (HTTR) is a graphite-moderated, helium gas-cooled test reactor with a maximum power of 30 MW. The HTTR aims not only to establish and upgrade the technological basis for the HTGRs but also to perform the innovative basic research on high temperature engineering with high temperature irradiation fields. It is planned that the HTTR is used to perform various engineering tests such as the safety demonstration test, high temperature test operation and irradiation test with large irradiation fields at high temperatures. This paper describes the design of the I-I type irradiation equipment developed as the first irradiation rig for the HTTR and does the planned dosimetry method at the first irradiation test. It was developed to perform in-pile creep test on a stainless steel with large standard size specimens in the HTTR. It can give great loads on the specimens stably and can control the irradiation temperature precisely. The in-core creep properties on the specimens are measured by newly developed differential transformers and the irradiation condition in the core is monitored by thermocouples and self-powered neutron detectors (SPNDs), continuously. The irradiated neutron fluence is assessed by neutron fluence monitors of small metallic wires after the irradiation. The obtained data at the first irradiation test can strongly be contributed to upgrade the technological basis for the HTGRs, since it is the first direct measurement of the in-core irradiation environments of the HTTR. (author)

Neutron Focusing Mirrors for Neutron Radiography of Irradiated Nuclear Fuel at Idaho National Laboratory

Science.gov (United States)

Rai, Durgesh K.; Wu, Huarui; Abir, Muhammad; Giglio, Jeffrey; Khaykovich, Boris

Post irradiation examination (PIE) of samples irradiated in nuclear reactors is a challenging but necessary task for the development on novel nuclear power reactors. Idaho National Laboratory (INL) has neutron radiography capabilities, which are especially useful for the PIE of irradiated nuclear fuel. These capabilities are limited due to the extremely high gamma-ray radiation from the irradiated fuel, which precludes the use of standard digital detectors, in turn limiting the ability to do tomography and driving the cost of the measurements. In addition, the small 250 kW Neutron Radiography Reactor (NRAD) provides a relatively weak neutron flux, which leads to low signal-to-noise ratio. In this work, we develop neutron focusing optics suitable for the installation at NRAD. The optics would separate the sample and the detector, potentially allowing for the use of digital radiography detectors, and would provide significant intensity enhancement as well. The optics consist of several coaxial nested Wolter mirrors and is suited for polychromatic thermal neutron radiation. Laboratory Directed Research and Development program of Idaho National Laboratory.

Evaluation of slow shutdown system flux detectors in Point Lepreau Generating Station - I: dynamic response characterization

Energy Technology Data Exchange (ETDEWEB)

Anghel, V.N.P. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Comeau, D. [New Brunswick Power Nuclear, Point Lepreau, New Brunswick (Canada); McKay, J.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Taylor, D. [New Brunswick Power Nuclear, Point Lepreau, New Brunswick (Canada)

2009-07-01

CANDU reactors are protected against reactor overpower by two independent shutdown systems: Shut Down System 1 and 2 (SDS1 and SDS2). At the Point Lepreau Generating Station (PLGS), the shutdown systems can be actuated by measurements of the neutron flux by Platinum-clad Inconel In-Core Flux Detectors (ICFDs). These detectors have a complex dynamic behaviour, characterized by 'prompt' and 'delayed' components with respect to immediate changes in the in-core neutron flux. The dynamic response components need to be determined accurately in order to evaluate the effectiveness of the detectors for actuating the shutdown systems. The amplitudes of the prompt and the delayed components of individual detectors were estimated over a period of several years by comparison of archived detector response data with the computed local neutron flux evolution for SDS1 and SDS2 reactor trips. This was achieved by custom-designed algorithms. The results of this analysis show that the dynamic response of the detectors changes with irradiation, with the SDS2 detectors having 'prompt' signal components that decreased significantly with irradiation. Some general conclusions about detector aging effects are also drawn. (author)

Double-sided FoxFET biased microstrip detectors

International Nuclear Information System (INIS)

Allport, P.P.; Carter, J.R.; Dunwoody, U.C.; Gibson, V.; Goodrick, M.J.; Beck, G.A.; Carter, A.A.; Martin, A.J.; Pritchard, T.W.; Bullough, M.A.; Greenwood, N.M.; Lucas, A.D.; Wilburn, C.D.

1994-01-01

The use of the field effect transistor, integrated onto AC-coupled silicon detectors, as a novel technique for biasing the implanted p + strips [P.P. Allport et al., Nucl. Instr. and Meth. A 310 (1991) 155], was first employed for the OPAL microvertex detector. The detector has proved very successful, with ladders of three single-sided detectors showing signal/noise of 22 : 1 with MX5 readout electronics [P.P. Allport et al., Nucl. Instr. and Meth. A 324 (1993) 34; Nucl. Phys. B (Proc. Suppl.) 32 (1993) 208]. This technique has been extended to bias also the n + strips and p strips on the ohmic side of a double-sided detector [P.P. Allport et al., Nucl. Instr. and Meth. A, to be submitted]. Full-size detectors with orthogonal readout have been fabricated by Micron and tested with MX7 readout on both sides. Both the junction and ohmic sides of these detectors have similar signal/noise values to those for single-sided wafers [P.P. Allport et al., Nucl. Instr. and Meth. A, to be submitted]. Test structures have been irradiated with beta particles to study the radiation hardness of the devices, and probe station electrical measurements of the detectors and test structures are presented. ((orig.))

EPR of alanine irradiated by neutrons

International Nuclear Information System (INIS)

Pivovarov, S.P.; Seredavina, T.A.; Zhdanov, S.V.; Mul'gin, S.I.; Zhakparov, R.K.

2001-01-01

In the work the first results of EPR studies of alanine, irradiated with diverse doses at neutron cyclotron generator different conditions and on the critical reactor stand are presented. A dose linearity dependence of EPR signal is observing, the methods of γ-background contribution separation are discussed. Obtain results is giving the basis to recommendation of alanine as an effective detector irradiation. However it is demanded the farther study on clarification of radiation sensitivity value dependence on the neutron energy spectrum form

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)

Influence of damage caused by Kr ions and neutrons on electrical properties of silicon detectors

CERN Document Server

Croitoru, N; Rancoita, P G; Rattaggi, M; Seidman, A

1999-01-01

In this paper, new measurements of physical properties of high-resistivity silicon, used in high-energy detectors, are presented. The obtained data contribute to the understanding of the causes which damage the 2electronic characteristics of the detection systems under irradiation of neutrons and ionized particles (Kr). The Hall effect coefficient (R sub H) and resistivity (rho) measurements as a function of temperature (T), for non-irradiated and irradiated by neutrons and Kr ions, were performed. The measurements of the Hall coefficient and resistivity of non-irradiated samples and irradiated at neutron fluences (PHI=9.9x10 sup 1 sup 0 n/cm sup 2 (neutrons) and PHI>=7.5x10 sup 8 Kr/cm sup 3 (ions), cannot be explained, considering the usual theoretical relations. The results, obtained in these experiments, have shown a change of mechanism of conduction due to the damaged regions, where localized levels are created, which are the main cause of the deviation of the electrical characteristics of the detectors ...

Development of a 3D CZT detector prototype for Laue Lens telescope

DEFF Research Database (Denmark)

Caroli, Ezio; Auricchio, Natalia; Del Sordo, Stefano

2010-01-01

We report on the development of a 3D position sensitive prototype suitable as focal plane detector for Laue lens telescope. The basic sensitive unit is a drift strip detector based on a CZT crystal, (~19×8 mm2 area, 2.4 mm thick), irradiated transversally to the electric field direction. The anode...

Detector Control System and Efficiency Performance for CMS RPC at GIF++

CERN Document Server

Gul, Muhammad; Cimmino, A; Crucy, S; Fagot, A; Rios, A A O; Tytgat, M; Zaganidis, N; Aly, S; Assran, Y; Radi, A; Sayed, A; Singh, G; Abbrescia, M; Iaselli, G; Maggi, M; Pugliese, G; Verwilligen, P; Doninck, W V; Colafranceschi, S; Sharma, A; Benussi, L; Bianco, S; Piccolo, D; Primavera, F; Bhatnagar, V; Kumari, R; Mehta, A; Singh, J; Ahmad, A; Asghar, M I; Muhammad, S; Awan, I A; Hoorani, H R; Ahmed, W; Shahzad, H; Shah, M A; Cho, S W; Choi, S Y; Hong, B; Kang, M H; Lee, K S; Lim, J H; Park, S K; Kim, M; Goutzvitz, M; Grenier, G; Lagarde, F; Estrada, C U; Pedraza, I; Severiano, C B; Carrillo Moreno, S; Vazquez Valencia, F; Pant, L M; Buontempo, S; Cavallo, N; Esposito, M; Fabozzi, F; Lanza, G; Lista, L; Meola, S; Merola, M; Orso, I; Paolucci, P; Thyssen, F; Braghieri, A; Magnani, A; Montagna, P; Riccardi, C; Salvini, P; Vai, I; Vitulo, P; Ban, Y; Qian, S J; Choi, M; Choi, Y; Goh, J; Kim, D; Aleksandrov, A; Hadjiiska, R; Iaydjiev, P; Rodozov, M; Stoykova, S; Sultanov, G; Vutova, M; Dimitrov, A; Litov, L; Pavlov, B; Petkov, P; Lomidze, D; Bagaturia, I; Avila, C; Cabrera, A; Sanabria, J C; Crotty, I; Vaitkus, J

2016-01-01

In the framework of the High Luminosity LHC upgrade program, the CMS muon group built several different RPC prototypes that are now under test at the new CERN Gamma Irradiation Facility (GIF++). A dedicated Detector Control System has been developed using the WinCC-OA tool to control and monitor these prototype detectors and to store the measured parameters data.

Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00371978; Gößling, Claus; Pernegger, Heinz

The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ...

ESR investigataions of electron-beam irradiated cellulose nitrate

International Nuclear Information System (INIS)

Chipara, M.I.; Catana, D.; Grecu, V.; Romero, J.R.; Chipara, D.

1994-01-01

Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

ESR investigataions of electron-beam irradiated cellulose nitrate

Energy Technology Data Exchange (ETDEWEB)

Chipara, M.I.; Catana, D. [Institute of Atomic Physics, Bucharest (Romania); Grecu, V.; Romero, J.R. [Bucharest Univ. (Romania). Faculty of Physics; Coca, S. [Chemical Research Inst., Bucharest (Romania); Chipara, D. [Research Inst. for Electrotechnics, Bucharest (Romania)

1994-10-01

Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author).

ESR investigations of electron-beam irradiated cellulose nitrate

International Nuclear Information System (INIS)

Chipara, M.I.; Grecu, V.; Catana, D.; Romero, J.R.; Coca, S.; Chipara, M.D.

1994-01-01

Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311), are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and it is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

Dynamic Efficiency Measurements for Irradiated ATLAS Pixel Single Chip Modules

CERN Document Server

Pfaff, Mike; Grosse-Knetter, Jorn

2011-01-01

The ATLAS pixel detector is the innermost subdetector of the ATLAS experiment. Due to this, the pixel detector has to be particularly radiation hard. In this diploma thesis effects on the sensor and the electronics which are caused by irradiation are examined. It is shown how the behaviour changes between an unirradiated sample and a irradiated sample, which was treated with the same radiation dose that is expected at the end of the lifetime of ATLAS. For this study a laser system, which is used for dynamic efficiency measurements was constructed. Furthermore, the behaviour of the noise during the detection of a particle was evaluated studied.

Thermoluminescent signal fading of encapsulated lif: Mg,Ti detectors in PTFE-Teflon registered trademark

International Nuclear Information System (INIS)

Sasho Nikolovski, Sasho; Nikolovska, Lidija; Velevska, Marija; Velev, Velko

2010-01-01

Fading is a process when the latent information of a detector is unintentionally lost mainly due to the thermal influence. Thermoluminescent (TL) detectors have different sensitivities as far as the fading effect. Encapsulated TL detectors mounted within shielded filter holders are used during the personal monitoring of occupationally exposed persons in R. Macedonia. PTFE-Teflon registered trademark polymer is an example of encapsulation material that has a temperature resistance and it allows the luminescence signal to pass through. Since the encapsulated TL detectors cannot be submitted to annealing treatment in an oven, another fading reduction method is needed. The TL evaluation method suggested in this work is based on a specific glow-curve region. Irradiations were conducted using 90Sr/90Y source. Post-irradiation fade investigations were conducted for evaluation periods that varied up to 4 months. Two areas of the TL glow-curve were selected with the WimRems software. They correspond to the high and the low fading emission peaks (the lower temperature peaks display a greater degree of thermal fading than the higher temperature peaks). Post-irradiation fade is a contributing factor that affects the response of a thermoluminescent (TL) phosphor as a function of time. PTFE - Polytetrafluoroethylene most well known by the DuPont brand name Teflon registered trademark. (Author)

Development of the dyed-track method for Kodak CN-85 detector

International Nuclear Information System (INIS)

Somogyi, G.; Toth-Szilagyi, M.; Varga, Z.; Monnin, M.; Lferde, M.

1984-01-01

The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors. (author)

Development of the dyed-track method for Kodak CN-85 detector

Energy Technology Data Exchange (ETDEWEB)

Somogyi, G.; Toth-Szilagyi, M.; Varga, Z. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete); Monnin, M.; Lferde, M. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire)

1984-01-01

The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors.

Investigation of radiation damage effects in neutron irradiated CCD

International Nuclear Information System (INIS)

Brau, James E.; Igonkina, Olga; Potter, Chris T.; Sinev, Nikolai B.

2005-01-01

A Charge Coupled Devices (CCD)-based vertex detector is a leading option for vertex detection at the future linear collider. A major issue for this application is the radiation hardness of such devices. Tests of radiation hardness of CCDs used in the SLD vertex detector, VXD3, have been reported earlier. The first measurements of 1998 involved a spare VXD3 CCD that was irradiated with neutrons from a radioactive source (Pu-Be), and from a nuclear reactor. In 2003, we had the opportunity to disassemble the VXD3 detector and study the nature of the radiation damage it incurred during 3 years of operation at SLC. In the preparation for this study, additional experiments with the spare VXD3 CCD were performed. These included measurements of trapping times in neutron irradiated CCDs. Results, reported here, will help us better understand the mechanism of radiation damage effects and develop techniques to minimize performance degradation due to radiation damage

Radiation damage in proton-irradiated epitaxial silicon detectors

Energy Technology Data Exchange (ETDEWEB)

Lange, Joern

2009-07-15

In this work radiation hardness of 75 {mu}m, 100 {mu}m and 150 {mu}m thick epitaxial silicon pad diodes of both standard and oxygenated material was investigated. Damage after 24 GeV/c proton irradiation in a 1MeV neutron equivalent fluence range between 10{sup 14} cm{sup -2} and 10{sup 16} cm{sup -2} was studied and isothermal annealing experiments at 80 C were carried out. Standard CV/IV measurements could be performed up to 4 x 10{sup 15} cm{sup -2}. The volume-normalised reverse current was found to increase linearly with fluence with a slope independent of the thickness and impurity concentration. However, due to large fluctuations the fluences had to be renormalised using the current-related damage parameter. Concerning the depletion voltage, nearly all materials remained at a moderate level up to 4 x 10{sup 15} cm{sup -2}. During short-term annealing acceptors annealed out, whereas others were introduced during the long-term annealing. The stable damage was characterised by donor removal at low fluences and fluence-proportional predominant donor introduction for highly irradiated diodes, depending on the oxygen level. No type inversion was observed. Time-resolved measurements with a new 670 nm laser-TCT setup made the determination of the trapping time constant with the charge correction method possible. The results agreed with expectations and showed a linear increase of trapping probability with fluence. The electric field exhibited a double peak structure in highly irradiated diodes. Charge collection efficiency measurements with {alpha}-particles were independent of oxygen concentration, but showed an improved efficiency for thinner diodes. A comparison to simulation revealed systematic discrepancies. A non-constant trapping time parameter was proposed as possible solution. (orig.)

Radiation damage in proton-irradiated epitaxial silicon detectors

International Nuclear Information System (INIS)

Lange, Joern

2009-07-01

In this work radiation hardness of 75 μm, 100 μm and 150 μm thick epitaxial silicon pad diodes of both standard and oxygenated material was investigated. Damage after 24 GeV/c proton irradiation in a 1MeV neutron equivalent fluence range between 10 14 cm -2 and 10 16 cm -2 was studied and isothermal annealing experiments at 80 C were carried out. Standard CV/IV measurements could be performed up to 4 x 10 15 cm -2 . The volume-normalised reverse current was found to increase linearly with fluence with a slope independent of the thickness and impurity concentration. However, due to large fluctuations the fluences had to be renormalised using the current-related damage parameter. Concerning the depletion voltage, nearly all materials remained at a moderate level up to 4 x 10 15 cm -2 . During short-term annealing acceptors annealed out, whereas others were introduced during the long-term annealing. The stable damage was characterised by donor removal at low fluences and fluence-proportional predominant donor introduction for highly irradiated diodes, depending on the oxygen level. No type inversion was observed. Time-resolved measurements with a new 670 nm laser-TCT setup made the determination of the trapping time constant with the charge correction method possible. The results agreed with expectations and showed a linear increase of trapping probability with fluence. The electric field exhibited a double peak structure in highly irradiated diodes. Charge collection efficiency measurements with α-particles were independent of oxygen concentration, but showed an improved efficiency for thinner diodes. A comparison to simulation revealed systematic discrepancies. A non-constant trapping time parameter was proposed as possible solution. (orig.)

Calibration of time of flight detectors using laser-driven neutron source

Energy Technology Data Exchange (ETDEWEB)

Mirfayzi, S. R.; Kar, S., E-mail: s.kar@qub.ac.uk; Ahmed, H.; Green, A.; Alejo, A.; Jung, D. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Krygier, A. G.; Freeman, R. R. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States); Clarke, R. [Central Laser Facility, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX (United Kingdom); Fuchs, J.; Vassura, L. [LULI, Ecole Polytechnique, CNRS, Route de Saclay, 91128 Palaiseau Cedex (France); Kleinschmidt, A.; Roth, M. [Institut für Kernphysik, Technische Universität Darmstadt, Schloßgartenstrasse 9, D-64289 Darmstadt,Germany (Germany); Morrison, J. T. [Propulsion Systems Directorate, Air Force Research Lab, Wright Patterson Air Force Base, Ohio 45433 (United States); Najmudin, Z.; Nakamura, H. [Blackett Laboratory, Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); Norreys, P. [Central Laser Facility, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX (United Kingdom); Department of Physics, University of Oxford, Oxford OX1 3PU (United Kingdom); Oliver, M. [Department of Physics, University of Oxford, Oxford OX1 3PU (United Kingdom); Zepf, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Helmholtz Institut Jena, D-07743 Jena (Germany); Borghesi, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Institute of Physics of the ASCR, ELI-Beamlines Project, Na Slovance 2, 18221 Prague (Czech Republic)

2015-07-15

Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil.

Calibration of time of flight detectors using laser-driven neutron source

Science.gov (United States)

Mirfayzi, S. R.; Kar, S.; Ahmed, H.; Krygier, A. G.; Green, A.; Alejo, A.; Clarke, R.; Freeman, R. R.; Fuchs, J.; Jung, D.; Kleinschmidt, A.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Oliver, M.; Roth, M.; Vassura, L.; Zepf, M.; Borghesi, M.

2015-07-01

Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil.

Calibration of time of flight detectors using laser-driven neutron source

International Nuclear Information System (INIS)

Mirfayzi, S. R.; Kar, S.; Ahmed, H.; Green, A.; Alejo, A.; Jung, D.; Krygier, A. G.; Freeman, R. R.; Clarke, R.; Fuchs, J.; Vassura, L.; Kleinschmidt, A.; Roth, M.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Oliver, M.; Zepf, M.; Borghesi, M.

2015-01-01

Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil

Influence of variation of etching conditions on the sensitivity of PADC detectors with a new evaluation method

International Nuclear Information System (INIS)

Fiechtner-Scharrer, A.; Mayer, S.; Boschung, M.; Whitelaw, A.

2011-01-01

At the Paul Scherrer Institut, a personal neutron dosimetry system based on chemically etched poly allyl diglycol carbonate (PADC) detectors and an automatic track counting (Autoscan 60) for neutron dose evaluations has been in routine use since 1998. Today, the hardware and the software of the Autoscan 60 are out of date, no spare components are available anymore and more sophisticated image-analysis systems are already developed. Therefore, a new evaluation system, the 'TASLIMAGE', was tested thoroughly in 2009 for linearity, reproducibility, influence of etching conditions and so forth, with the intention of replacing the Autoscan 60 in routine evaluations. The TASLIMAGE system is based on a microscope (high-quality Nikon optics) and an ultra-fast three-axis motorised control for scanning the detectors. In this paper, the TASLIMAGE system and its possibilities for neutron dose calculation are explained in more detail and the study of the influence of the variation of etching conditions on the sensitivity and background of the PADC detectors is described. The etching temperature and etching duration were varied, which showed that the etching conditions do not have a significant influence on the results of non-irradiated detectors. However, the sensitivity of irradiated detectors decreases by 5 % per 1 deg. C when increasing the etching temperature. For the variation of the etching duration, the influence on the sensitivity of irradiated detectors is less pronounced. (authors)

Proposals of counting method for bubble detectors and their intercomparisons

International Nuclear Information System (INIS)

Ramalho, Eduardo; Silva, Ademir X.; Bellido, Luis F.; Facure, Alessandro; Pereira, Mario

2009-01-01

The study of neutron's spectrometry and dosimetry has become significantly easier due to relatively new devices called bubble detectors. Insensitive to gamma rays and composed by superheated emulsions, they still are subjects of many researches in Radiation Physics and Nuclear Engineering. In bubble detectors, either exposed to more intense neutron fields or for a long time, when more bubbles are produced, the statistical uncertainty during the dosimetric and spectrometric processes is reduced. A proposal of this nature is set up in this work, which presents ways to perform counting processes for bubble detectors and an updated proceeding to get the irradiated detectors' images in order to make the manual counting easier. Twelve BDS detectors were irradiated by RDS111 cyclotron from IEN's (Instituto de Engenharia Nuclear) and photographed using an assembly specially designed for this experiment. Counting was proceeded manually in a first moment; simultaneously, ImagePro was used in order to perform counting automatically. The bubble counting values, either manual or automatic, were compared and the time to get them and their difficult levels as well. After the bubble counting, the detectors' standardizes responses were calculated in both cases, according to BDS's manual and they were also compared. Among the results, the counting on these devices really becomes very hard at a large number of bubbles, besides higher variations in counting of many bubbles. Because of the good agreement between manual counting and the custom program, the last one revealed a good alternative in practical and economical levels. Despite the good results, the custom program needs of more adjustments in order to achieve more accuracy on higher counting on bubble detectors for neutron measurement applications. (author)

Status of the Silicon Strip Detector at CMS

CERN Document Server

Simonis, H J

2008-01-01

The CMS Tracker is the world's largest silicon detector. It has only recently been moved underground and installed in the 4T solenoid. Prior to this there has been an intensive testing on the surface, which confirms that the detector system fully meets the design specifications. Irradiation studies with the sensor material shows that the system will survive for at least 10 years in the harsh radiation environment prevailing within the Tracker volume. The planning phase for SLHC as the successor of LHC, with a ten times higher luminosity at the same energy has already begun. First R\\&D studies for more robust detector materials and a new Tracker layout have started.

Experimental characterization of semiconductor-based thermal neutron detectors

Energy Technology Data Exchange (ETDEWEB)

Bedogni, R., E-mail: roberto.bedogni@lnf.infn.it [IFNF—LNF, via E. Fermi n. 40, 00044 Frascati, Roma (Italy); Bortot, D.; Pola, A.; Introini, M.V.; Lorenzoli, M. [Politecnico di Milano, Dipartimento di Energia, via La Masa 34, 20156 Milano (Italy); INFN—Milano, Via Celoria 16, 20133 Milano (Italy); Gómez-Ros, J.M. [IFNF—LNF, via E. Fermi n. 40, 00044 Frascati, Roma (Italy); CIEMAT, Av. Complutense 40, 28040 Madrid (Spain); Sacco, D. [IFNF—LNF, via E. Fermi n. 40, 00044 Frascati, Roma (Italy); INAIL—DIT, Via di Fontana Candida 1, 00040 Monteporzio Catone (Italy); Esposito, A.; Gentile, A.; Buonomo, B. [IFNF—LNF, via E. Fermi n. 40, 00044 Frascati, Roma (Italy); Palomba, M.; Grossi, A. [ENEA Triga RC-1C.R. Casaccia, via Anguillarese 301, 00060 S. Maria di Galeria, Roma (Italy)

2015-04-21

In the framework of NESCOFI@BTF and NEURAPID projects, active thermal neutron detectors were manufactured by depositing appropriate thickness of {sup 6}LiF on commercially available windowless p–i–n diodes. Detectors with different radiator thickness, ranging from 5 to 62 μm, were manufactured by evaporation-based deposition technique and exposed to known values of thermal neutron fluence in two thermal neutron facilities exhibiting different irradiation geometries. The following properties of the detector response were investigated and presented in this work: thickness dependence, impact of parasitic effects (photons and epithermal neutrons), linearity, isotropy, and radiation damage following exposure to large fluence (in the order of 10{sup 12} cm{sup −2})

Study of long-term operation of triple-GEM detectors for the high rate environment in CMS

CERN Document Server

Merlin, Jeremie Alexandre

2013-01-01

The CMS GEM collaboration is working on the possible instrumentation of the high-eta region of the CMS Endcap with Gas Electron Multiplier (GEM) detectors, a technology capable to sustain the hostile environment that will be encountered at the high-luminosity LHC. To ensure the long-term operation of large triple-GEM detectors in the CMS experiment, we are performing a set of studies in order to measure and understand the aging effect of triple-GEM Muon chambers. The aging includes all the processes that lead to a significant degradation of the performances of the detector gain drop, non-uniformity, dark current, discharges and resolution loss. The project is focused on monitoring continuously the response of the detector when irradiated by a source of Cs 137 at CERN in the Gamma Irradiation Facility (GIF). Moreover, the new technology employed for stretching the GEM foils, so called NS2, introduces new, carefully chosen materials and components in the detectors. Outgassing tests are performed in order to va...

Development of Hybrid and Monolithic Silicon Micropattern Detectors

CERN Multimedia

Beker, H; Snoeys, W; Campbell, M; Lemeilleur, F; Ropotar, I

2002-01-01

%RD-19 \\\\ \\\\ In a collaborative effort between particle physics institutes and microelectronics industry we are undertaking the development of true 2-dimensional semiconductor particle detectors with on-chip signal processing and information extraction: the so-called micropattern detector. This detector is able to cope in a robust way with high multiplicity events at high rates, while allowing for a longer detector lifetime under irradiation and a thinner sensitive depletion region. Therefore, it will be ideally suited for the complicated events in the LHC p-p collider experiments. Following a $^{\\prime}$stepping stone$^{\\prime}$ approach several telescopes of pixel planes, totalling now 600 cm$^{2}$ with \\(>\\)~1~M elements have been used in the WA97, NA50 and NA57 lead ion experiments. This new technology has facilitated the tracking considerably (see Fig.1). Not only Si but also GaAs and possibly diamond matrices can be connected to the readout matrix. Tests with GaAs pixel detectors with the RD-19 readout ...

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)

Characterisation of silicon detectors for the LHCb Vertex Locator Upgrade

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00401830

The LHCb Vertex Locator must be upgraded in the next long shutdown of the LHC, starting at the end of 2018. This is due to the increased occupancy. The current silicon strip detector is being upgraded to a silicon pixel detector. The prototype sensors for this detector were tested thoroughly before a final design will be chosen. The testing was done with the Timepix3 Telescope, which was commissioned in the summer of 2014. The charge collected by the sensors and efficiency of the sensors were investigated. After maximum irradiation, of 8$\\times$10$^{15}$ 1 MeV n$_{eq}$/cm$^{2}$, the sensors must have a most probable value of collected charge of 6000 electrons before 1000 V or breakdown, whichever comes first. The sensors must also have a high efficiency at maximum irradiation of 8$\\times$10$^{15}$ 1 MeV n$_{eq}$/cm$^{2}$. All tested sensors reach these criteria. All sensors reach 6000 electrons between 600 V and 800 V and have a cluster finding efficiency of over 95\\% at the respective voltages. Overall, a 15...

Concerns about the dynamic responses of in-core flux detectors

Energy Technology Data Exchange (ETDEWEB)

Cuttler, J.M., E-mail: jerrycuttler@rogers.com [Cuttler & Associates Inc., Mississauga, Ontario (Canada); Gill, H.; Scrannage, R.; Paquette, P., E-mail: jerrycuttler@rogers.com [Bruce Power, Tiverton, Ontario (Canada)

2012-07-01

CANDUs are determining the dynamic responses of flux detectors by a method open to question. It ignores relative changes in local flux conditions, which are significant during trips. Calculated prompt fractions (PFs) are widespread. The SIR detector development calculated the PF change with irradiation on a physical basis. Measurements were made over many years. The current results do not agree with the 1996 predictions. Some values are below the safety analysis limit. This has resulted in detector replacement, imposition of CPPF penalties on trip margins, additional safety analyses and other actions. This paper shows that such measurements are not required. (author)

Silicon microstrip detectors for the ATLAS SCT

Czech Academy of Sciences Publication Activity Database

Robinson, D.; Allport, P.; Andricek, L.; Böhm, Jan; Buttar, C.; Carter, J. R.; Chilingarov, A.; Clark, A. G.; Feriere, D.; Fuster, J.

2002-01-01

Roč. 485, 1-2 (2002), s. 84-88 ISSN 0168-9002 R&D Projects: GA MPO RP-4210/69 Institutional research plan: CEZ:AV0Z1010920 Keywords : ATLAS SCT * silicon microstrip detectors * irradiation * quality control Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.167, year: 2002

Fiscal 2000 achievement report on the venture business assisting type regional consortium-Core industry creation type. Development of radiation detector utilizing surface reforming effect of irradiation; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo seika hokokusho. Hoshasen shosha ni yoru hyomen kaishitsu koka wo mochiita hoshasen kenshutsuki no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

It has been clarified that the use of some kinds of semiconductor films, such as a rutile type titanium oxide film or a zirconium oxide film, results in a stable photocatalytic reaction in an intensive radioactivity region. In this effort, the effect is applied for the development of a FET (field effect transistor) type radiation detector capable of stable operation under high dose irradiation circumstances. Semiconductor materials such as a rutile type titanium oxide were subjected to irradiation tests on the ground, in which changes in their physical properties such as wettability or conductance were examined and the mechanism of surface reforming under irradiation was elucidated, and proper materials were selected. A prototype high radiation detector was fabricated that covers a 1mGy/hr-4kGy/hr region. For the establishment of a technology for growing spherical semiconductor crystals under microgravity, basic experiments were conducted using a free-fall facility at the Japan Microgravity Center. Basic experiments were conducted for the fabrication of a prototype radiation detector to operate in a high radiation region from 0.1kGy/hr to 2kGy/hr and beyond, and a prototype spherical semiconductor radiation detector was fabricated. Achievements of the effort are mentioned above. (NEDO)

Characterization of proton and neutron irradiated low resistivity p-on-n magnetic Czochralski ministrip sensors and diodes

International Nuclear Information System (INIS)

Pacifico, Nicola; Dolenc Kittelmann, Irena; Fahrer, Manuel; Moll, Michael; Militaru, Otilia

2011-01-01

Transient Current Technique (TCT) and Charge Collection Efficiency (CCE) measurements were performed on low resistivity (280Ωcm) n-bulk, p-readout magnetic Czochralski ministrip sensors and diodes. The detectors were irradiated with neutrons and 24 GeV/c protons up to a total NIEL equivalent fluence of 8×10 15 /cm 2 . The study was addressed to assess the radiation tolerance of the detectors up to fluences expected in the next generations of High Energy Physics experiments. The charge collection efficiency after irradiation was found to be much higher than for standard FZ silicon p-in-n sensors. The underlying physics of this remarkable result was investigated by performing Edge-TCT measurements on one of the neutron irradiated ministrip sensors to extract detailed informations about the field and efficiency profiles of the detector.

Modifications in the optical and thermal properties of a CR-39 polymeric detector induced by high doses of γ-radiation

Science.gov (United States)

Saad, A. F.; Ibraheim, Mona H.; Nwara, Aya M.; Kandil, S. A.

2018-04-01

Effects of γ-radiation on the optical and thermal properties of a poly allyl diglycol carbonate (PADC), a form of CR-39, polymer have been investigated. CR-39 detectors were exposed to γ-rays at very high doses ranging from 5.0 × 105 to 3.0 × 106 Gy. The induced changes were analyzed using ultraviolet-visible spectroscopy (UV-VIS) in absorbance mode, and thermogravimetric analysis (TGA). The UV-visible spectra of the virgin and γ-irradiated CR-39 polymer detectors displayed a significant decreasing trend in their optical energy band gaps for indirect transitions, whereas for the direct ones showed a little change. This drop in the energy band gap with increasing dose is discussed on the basis of the gamma irradiation induced modifications in the CR-39 polymeric detector. The TGA thermograms show that the weight loss rate increased with increase in dose, which may be due to the disordered system via scission followed by crosslinking in the irradiated polymer detector. The TGA thermograms also indicated that the CR-39 detector decomposed in three/four stages for the virgin and irradiated samples. The activation energy for thermal decomposition was determined using a type of Arrhenius equation based on the TGA experimental results. These experimental results so obtained can be well used in radiation dosimetry.

Study on the fast neutron sensitivity of thermoluminescent detectors

International Nuclear Information System (INIS)

Szabo, P.P.; Palfalvi, J.

1984-03-01

Fast neutron (14.7 MeV) sensitivity of several thermoluminescent detectors was determined. The investigated detectors were MTS-N type pellets (made in Poland) used routinely in the authors' institute for personnel dosimetry, 7 LiF powder used for accident dosimetry, CaSO 4 :Dy and CaSO 4 :Tm powders (made in Hungary) used for enviromental monitoring and space dosimetry. Both free-in-air and on-phantom irradiations were performed. The new results are compared with responses calculated and measured earlier. (author)

Development of high resolution x-ray CT technique for irradiated fuel assembly

Energy Technology Data Exchange (ETDEWEB)

Ishimi, Akihiro; Katsuyama, Kozo; Maeda, Koji; Asaga, Takeo [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan)

2012-03-15

High X-ray CT technique was developed to observe the irradiation performance of FBR fuel assembly and MOX fuel. In this technique, the high energy X-ray pulse (12MeV) was used synchronizing detection system with the X-ray pulse to reduce the effect of the gamma ray emissions from the irradiated fuel assembly. In this study, this technique was upgraded to obtain high resolution X-ray CT image. In this upgrading, the collimator which had slit width of 0.1 mm and X-ray detector of a highly sensitive silicon semiconductor detector (100 channels) was introduced in the X-ray CT system. As a result of these developments, high resolution X-ray CT images could be obtained on the transverse cross section of irradiated fuel assembly. (author)

Silicon strip detectors for the ATLAS HL-LHC upgrade

CERN Document Server

Gonzalez Sevilla, S; The ATLAS collaboration

2011-01-01

The LHC upgrade is foreseen to increase the ATLAS design luminosity by a factor ten, implying the need to build a new tracker suited to the harsh HL-LHC conditions in terms of particle rates and radiation doses. In order to cope with the increase in pile-up backgrounds at the higher luminosity, an all silicon detector is being designed. To successfully face the increased radiation dose, a new generation of extremely radiation hard silicon detectors is being designed. We give an overview of the ATLAS tracker upgrade project, in particular focusing on the crucial innermost silicon strip layers. Results from a wide range of irradiated silicon detectors for the strip region of the future ATLAS tracker are presented. Layout concepts for lightweight yet mechanically very rigid detector modules with high service integration are shown.

Modifications of the optical properties for DAM-ADC nuclear track detector exposed to alpha particles

Science.gov (United States)

Rammah, Y. S.; Awad, E. M.

2018-05-01

Modifications of the optical properties of diallyl maleate-allyl diglycol carbonate (DAM-ADC) nuclear detector induced by alpha particles are described. DAM-ADC samples were irradiated perpendicularly by thin 241Am disk source that emits alpha particles with 5.48 MeV. The optical absorption has been measured using the ultraviolet-visible (UV-1100) spectroscopy. It was found that DAM-ADC polymer shows substantial modifications in its optical characteristics upon irradiated with alpha particles with different energies. The optical energy band gap (Egap) for the detector was calculated for the direct and the indirect allowed transitions in K-space using two approaches (Tauc's model and absorption spectrum fitting (ASF) method). Urbach's energy (Ea), number of carbon atoms per conjugated length (N), number of carbon atoms per cluster (M), and refractive index (n) for the present samples were determined. Results reveal that the values of energy gap in direct transition are greater than those of indirect, before and after irradiation. (Egap), (Ea), (N), (M), and (n) of the present samples are changed significantly with irradiation time and value of alpha energy. Results reflect the possibility of using DAM-ADC polymer track detectors to estimate alpha particle energies using the variation of the absorbance.

Advances in the project about Pin type silicon radiation detectors; Avances en el proyecto sobre detectores de radiacion de silicio tipo PIN

Energy Technology Data Exchange (ETDEWEB)

Ramirez F, J. [Instituto Nacional de Investigaciones Nucleares, Laboratorio de Detectores de Radiacion, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Cerdeira, A.; Aceves, M.; Diaz, A.; Estrada, M.; Rosales, P.; Cabal, A.E.; Montano L, M.; Leyva, A

1998-07-01

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)

Characterization of irradiation induced deep and shallow impurities

Science.gov (United States)

Treberspurg, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Krammer, Manfred; Valentan, Manfred

2013-12-01

Silicon Detectors close to the interaction point of the High Luminosity Large Hardron Collider (HL-LHC) have to withstand a harsh irradiation environment. In order to evaluate the behaviour of shallow and deep defects, induced by neutron irradiation, spreading resistance resistivity measurements and capacitance voltage measurements have been performed. These measurements, deliver information about the profile of shallow impurities after irradiation as well as indications of deep defects in the Space Charge Region (SCR) and the Electrical Neutral Bulk (ENB). By considering the theoretical background of the measurement both kinds of defects can be investigated independently from each other.

Characterization of irradiation induced deep and shallow impurities

Energy Technology Data Exchange (ETDEWEB)

Treberspurg, Wolfgang, E-mail: wolfgang.treberspurg@oeaw.ac.at; Bergauer, Thomas; Dragicevic, Marko; Krammer, Manfred; Valentan, Manfred

2013-12-21

Silicon Detectors close to the interaction point of the High Luminosity Large Hardron Collider (HL-LHC) have to withstand a harsh irradiation environment. In order to evaluate the behaviour of shallow and deep defects, induced by neutron irradiation, spreading resistance resistivity measurements and capacitance voltage measurements have been performed. These measurements, deliver information about the profile of shallow impurities after irradiation as well as indications of deep defects in the Space Charge Region (SCR) and the Electrical Neutral Bulk (ENB). By considering the theoretical background of the measurement both kinds of defects can be investigated independently from each other.

Characterization of irradiation induced deep and shallow impurities

International Nuclear Information System (INIS)

Treberspurg, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Krammer, Manfred; Valentan, Manfred

2013-01-01

Silicon Detectors close to the interaction point of the High Luminosity Large Hardron Collider (HL-LHC) have to withstand a harsh irradiation environment. In order to evaluate the behaviour of shallow and deep defects, induced by neutron irradiation, spreading resistance resistivity measurements and capacitance voltage measurements have been performed. These measurements, deliver information about the profile of shallow impurities after irradiation as well as indications of deep defects in the Space Charge Region (SCR) and the Electrical Neutral Bulk (ENB). By considering the theoretical background of the measurement both kinds of defects can be investigated independently from each other

Design, construction and testing of a self-powered neutron detector

International Nuclear Information System (INIS)

Correa, R.F.

1987-01-01

The design, construction and testing of a self-powered neutron detector (SPN) and associated electronics are described. Several tests were performed giving information about dielectrical properties of detector and cable, gamma spectra induced in the detector through reactor irradiation, detector response as a function of neutron flux, current stability and reproductibility with the neutron flux. The gamma and neutron sensitivities were also evaluated, by means of thermoluminescent dosimeters and gold foils as references. The test results are presented and show that the detector response is reliable. The gamma and neutron sensitivities are in agreement with those found in the available literature. Nevertheless, a ceramic insulated cable should be employed for permanent use in a reactor. The tests were performed in a 100 KW TRIGA Mark I reactor at the Centro de Desenvolvimento da Tecnologia Nuclear of NUCLEBRAS, in Belo Horizonte, Brazil. (author) [pt

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)

Opto-chemical response of Makrofol-KG to swift heavy ion irradiation

Indian Academy of Sciences (India)

In the present study, the effects of swift heavy ion beam irradiation on the structural, chemical and optical properties of Makrofol solid-state nuclear track detector (SSNTD) were investigated. Makrofol-KG films of 40 m thickness were irradiated with oxygen beam (8+) with fluences ranging between 1010 ion/cm2 and 1012 ...

Irradiation test of mirror samples for the LHCb SciFi tracker

CERN Document Server

Joram, Christian; Gavardi, Laura; Ravotti, Federico; Schneider, Thomas

2016-01-01

The optical mirrors at the inner ends of the SciFi fibre modules in the upgraded LHCb detector will be exposed to an ionising dose reaching 35 kGy for an integrated luminosity of 50 /fb. This note describes a campaign at the cyclotron at KIT where 7 different samples were irradiated with 23 MeV protons. The samples consisted of plastic scintillator tiles, on which two different mirror foils – aluminised mylar and 3M ESR - were attached with two different glues – Epotek H301-2FL and Dow Corning RTV 3145. The transmission and/or reflectivity of the samples were measured before and after irradiation. The measurements reveal the combination of 3M ESR foil and Epotek H301-2FL to give the highest reflectivity, before and also after irradiation. In all cases, the irradiation leads only to a small, i.e. less than 10%, degradation of the transmission or reflectivity. From a radiation hardness point of view, all investigated mirror samples qualify for use in the SciFi detector.

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

A study of the thermoluminescent properties of CVD diamond detectors

International Nuclear Information System (INIS)

Marczewska, B.; Bilski, P.; Olko, P.; Rebisz, M.; Nesladek, M.; Waligorski, M.P.R.

2002-01-01

A batch of 20 diamond detectors obtained by the chemical vapour deposition (CVD) method at the Institute for Materials Research at the Limburg University, Belgium, was investigated with respect to their thermoluminescent (TL) properties. The investigated detectors demonstrate TL sensitivity similar to that of the standard LiF:Mg, Ti (MTS) thermoluminescent detectors, lack of fading after two weeks from irradiation and apparent linearity of dose response. In spite of the persistent fluctuation of individual detector sensitivity observed in this batch, a new annealing procedure improved the stability of the TL signal. It has been concluded that 1 h annealing at 350 C assures the highest reproducibility for this set of detectors. A 30% discrepancy of the value of the TL signal between individual detectors from the batch may be caused by non-uniform distribution of dopants in the volume of the CVD diamond. A prototype of a planar TL reader equipped with a CCD camera was employed in this investigation. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

Characterization of proton and neutron irradiated low resistivity p-on-n magnetic Czochralski ministrip sensors and diodes

Energy Technology Data Exchange (ETDEWEB)

Pacifico, Nicola, E-mail: nicola.pacifico@cern.ch [CERN, Geneva (Switzerland); Dolenc Kittelmann, Irena; Fahrer, Manuel; Moll, Michael [CERN, Geneva (Switzerland); Militaru, Otilia [UCL, Louvain (Belgium)

2011-12-01

Transient Current Technique (TCT) and Charge Collection Efficiency (CCE) measurements were performed on low resistivity (280{Omega}cm) n-bulk, p-readout magnetic Czochralski ministrip sensors and diodes. The detectors were irradiated with neutrons and 24 GeV/c protons up to a total NIEL equivalent fluence of 8 Multiplication-Sign 10{sup 15}/cm{sup 2}. The study was addressed to assess the radiation tolerance of the detectors up to fluences expected in the next generations of High Energy Physics experiments. The charge collection efficiency after irradiation was found to be much higher than for standard FZ silicon p-in-n sensors. The underlying physics of this remarkable result was investigated by performing Edge-TCT measurements on one of the neutron irradiated ministrip sensors to extract detailed informations about the field and efficiency profiles of the detector.

Position-sensitive silicon strip detector characterization using particle beams

CERN Document Server

Maenpaeae, Teppo

2012-01-01

Silicon strip detectors are fast, cost-effective and have an excellent spatial resolution.They are widely used in many high-energy physics experiments. Modern high energyphysics experiments impose harsh operation conditions on the detectors, e.g., of LHCexperiments. The high radiation doses cause the detectors to eventually fail as a resultof excessive radiation damage. This has led to a need to study radiation tolerance usingvarious techniques. At the same time, a need to operate sensors approaching the endtheir lifetimes has arisen.The goal of this work is to demonstrate that novel detectors can survive the environment that is foreseen for future high-energy physics experiments. To reach this goal,measurement apparatuses are built. The devices are then used to measure the propertiesof irradiated detectors. The measurement data are analyzed, and conclusions are drawn.Three measurement apparatuses built as a part of this work are described: two telescopes measuring the tracks of the beam of a particle acceler...

Smart skin structures for identifying and locating laser irradiation

Energy Technology Data Exchange (ETDEWEB)

LaDelfe, P.C.; Goeller, R.M.; Murray, H.S.

1992-12-31

A pyramidal arrangement of wavelength-selective optical detectors can be used to determine the identity (wavelength), intensity, and direction-of-arrival of faser irradiation. The advantages of this technique are that only unobtrusive, skin-like structures are required and that large collection areas provide high sensitivity. The disadvantage is that the angular resolution (approximately 5 degrees in a 60 degree field-of--view) is less than that which can be achieved using methods requiring thicker structures. The detector elements are large-area, polyvinylidine fluoride, pyroelectric devices with wavelength selective coatinits. Four identical arrays of these elements are situated on the top and sides of a frustrated, three--sided prism. Since only the relative orientations are significant, these faces can be selected regions on the surface of an existing structure. We first describe the construction of the detectors and the system, then develop the mathematical description of the system. Using coated detectors whose performance has been experimentally verified, we will model the response to in-channel, monochromatic irradiation and then describe the data analysis algorithm. Although we will limit our model to a simple, two-channel system, the concept and algorithm can easily be extended to a system of any reasonable number of nonoverlapping channels.

Smart skin structures for identifying and locating laser irradiation

Energy Technology Data Exchange (ETDEWEB)

LaDelfe, P.C.; Goeller, R.M.; Murray, H.S.

1992-01-01

A pyramidal arrangement of wavelength-selective optical detectors can be used to determine the identity (wavelength), intensity, and direction-of-arrival of faser irradiation. The advantages of this technique are that only unobtrusive, skin-like structures are required and that large collection areas provide high sensitivity. The disadvantage is that the angular resolution (approximately 5 degrees in a 60 degree field-of--view) is less than that which can be achieved using methods requiring thicker structures. The detector elements are large-area, polyvinylidine fluoride, pyroelectric devices with wavelength selective coatinits. Four identical arrays of these elements are situated on the top and sides of a frustrated, three--sided prism. Since only the relative orientations are significant, these faces can be selected regions on the surface of an existing structure. We first describe the construction of the detectors and the system, then develop the mathematical description of the system. Using coated detectors whose performance has been experimentally verified, we will model the response to in-channel, monochromatic irradiation and then describe the data analysis algorithm. Although we will limit our model to a simple, two-channel system, the concept and algorithm can easily be extended to a system of any reasonable number of nonoverlapping channels.

Polycrystalline diamond detectors with three-dimensional electrodes

Energy Technology Data Exchange (ETDEWEB)

Lagomarsino, S., E-mail: lagomarsino@fi.infn.it [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Bellini, M. [INO-CNR Firenze, Largo E. Fermi 6, 50125 Firenze (Italy); Brianzi, M. [INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Carzino, R. [Smart Materials-Nanophysics, Istituto Italiano di Tecnologia, Genova, Via Morego 30, 16163 Genova (Italy); Cindro, V. [Joseph Stefan Institute, Jamova Cesta 39, 1000 Ljubljana (Slovenia); Corsi, C. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); LENS Firenze, Via N. Carrara 1, 50019 Sesto Fiorentino (Italy); Morozzi, A.; Passeri, D. [INFN Perugia, Perugia (Italy); Università degli Studi di Perugia, Dipartimento di Ingegneria, via G. Duranti 93, 06125 Perugia (Italy); Sciortino, S. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

2015-10-01

The three-dimensional concept in diamond detectors has been applied, so far, to high quality single-crystal material, in order to test this technology in the best available conditions. However, its application to polycrystalline chemical vapor deposited diamond could be desirable for two reasons: first, the short inter-electrode distance of three-dimensional detectors should improve the intrinsically lower collection efficiency of polycrystalline diamond, and second, at high levels of radiation damage the performances of the poly-crystal material are not expected to be much lower than those of the single crystal one. We report on the fabrication and test of three-dimensional polycrystalline diamond detectors with several inter-electrode distances, and we demonstrate that their collection efficiency is equal or higher than that obtained with conventional planar detectors fabricated with the same material. - Highlights: • Pulsed laser fabrication of polycristalline diamond detectors with 3D electrodes. • Measurement of the charge collection efficiency (CCE) under beta irradiation. • Comparation between the CCE of 3D and conventional planar diamond sensors. • A rationale for the behavior of three-dimensional and planar sensors is given.

The effect of incremental gamma-ray doses and incremental neutron fluences upon the performance of self-biased sup 1 sup 0 B-coated high-purity epitaxial GaAs thermal neutron detectors

CERN Document Server

Gersch, H K; Simpson, P A

2002-01-01

High-purity epitaxial GaAs sup 1 sup 0 B-coated thermal neutron detectors advantageously operate at room temperature without externally applied voltage. Sample detectors were systematically irradiated at fixed grid locations near the core of a 2 MW research reactor to determine their operational neutron dose threshold. Reactor pool locations were assigned so that fast and thermal neutron fluxes to the devices were similar. Neutron fluences ranged between 10 sup 1 sup 1 and 10 sup 1 sup 4 n/cm sup 2. GaAs detectors were exposed to exponential fluences of base ten. Ten detector designs were irradiated and studied, differentiated between p-i-n diodes and Schottky barrier diodes. The irradiated sup 1 sup 0 B-coated detectors were tested for neutron detection sensitivity in a thermalized neutron beam. Little damage was observed for detectors irradiated at neutron fluences of 10 sup 1 sup 2 n/cm sup 2 and below, but signals noticeably degraded at fluences of 10 sup 1 sup 3 n/cm sup 2. Catastrophic damage was appare...

Implantation of total body irradiation in radiotherapy

International Nuclear Information System (INIS)

Habitzreuter, Angela Beatriz

2010-01-01

Before implementing a treatment technique, the characteristics of the beam under irradiation conditions must be well acknowledged and studied. Each one of the parameters used to calculate the dose has to be measured and validated before its utilization in clinical practice. This is particularly necessary when dealing with special techniques. In this work, all necessary parameters and measurements are described for the total body irradiation implementation in facilities designed for conventional treatments that make use of unconventional geometries to generate desired enlarged field sizes. Furthermore, this work presents commissioning data of this modality at Hospital das Clinicas of Sao Paulo using comparison of three detectors types for measurements of entrance dose during total body irradiation treatment. (author)

Improvement in breakdown characteristics with multiguard structures in microstrip silicon detectors for CMS

International Nuclear Information System (INIS)

Bacchetta, N.; Bisello, D.; Candelori, A.; Rold, M. Da; Descovich, M.; Kaminski, A.; Messineo, A.; Rizzo, F.; Verzellesi, G.

2001-01-01

To obtain full charge collection the CMS silicon detectors should be able to operate at high bias voltage. We observed that multiguard structures enhance the breakdown performance of the devices on several tens of baby detectors designed for CMS. The beneficial effects of the multiguard structures still remains after the strong neutron irradiation performed to simulate the operation at the LHC

Improvement in breakdown characteristics with multiguard structures in microstrip silicon detectors for CMS

CERN Document Server

Bacchetta, N; Candelori, A; Da Rold, M; Descovich, M; Kaminski, A; Messineo, A; Rizzo, F; Verzellesi, G

2001-01-01

To obtain full charge collection the CMS silicon detectors should be able to operate at high bias voltage. We observed that multiguard structures enhance the breakdown performance of the devices on several tens of baby detectors designed for CMS. The beneficial effects of the multiguard structures still remains after the strong neutron irradiation performed to simulate the operation at the LHC. (3 refs).

Design constrution and testing of a self-powered neutron detector

International Nuclear Information System (INIS)

Correa, R.F.

1987-01-01

The design, contruction and testing of a self-powered neutron detector (SPN) and associated electronics are described. Several tests were performed giving information about dielectrical properties od detector and cable, gamma spectra induced in the detector through reactor irradiation, detector response as a function of neutron flux, current stability and reproductibility with the neutron flux. The gamma and neutron sensitivities were also evaluated, by means of thermoluminescent dosimeters and gold foils as references. The test results are presented and show that the detector response is reliable. The gamma and neutron sensitivities are in agreement with those found in the available literature. Neverthe less, a ceramic insulated cable should be employed for permanent use in a reactor. The tests were perfomance in a 100 kW TRIGA Mark I reactor at the Centro de Desenvolvimento da Tecnologia Nuclear of NUCLEBRAS,in Belo Horizonte, Brazil. (Author) [pt

Process effects on leakage current of Si-PIN neutron detectors with porous microstructure

Energy Technology Data Exchange (ETDEWEB)

Yu, Baoning; Zhao, Kangkang; Yang, Taotao [Beijing University of Technology, Chaoyang District, Pingleyuan 100, 100124 Beijing (China); Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Ruoshui Road 398, 215123 Suzhou (China); Jiang, Yong; Fan, Xiaoqiang [Institute of Nuclear Physics and Chemistry, CAEP, Mianshan Road 64, 621900 Mianyang (China); Lu, Min [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Ruoshui Road 398, 215123 Suzhou (China); Han, Jun [Beijing University of Technology, Chaoyang District, Pingleyuan 100, 100124 Beijing (China)

2017-06-15

Using the technique of Microfabrication, such as deep silicon dry etching, lithography, etc. Si-PIN neutron detectors with porous microstructure have been successfully fabricated. In order to lower the leakage current, the key fabrication processes, including the Al windows opening, deep silicon etching and the porous side wall smoothing, have been optimized. The cross-section morphology and current-voltage characteristics have been measured to evaluate the microfabrication processes. With the optimized conditions presented by the measurements, a neutron detector with a leakage current density of 2.67 μA cm{sup -2} at a bias of -20 V is obtained. A preliminary neutron irradiation test with {sup 252}Cf neutron source has also been carried out. The neutron irradiation test shows that the neutron detection efficiency of the microstructured neutron detectors is almost 3.6 times higher than that of the planar ones. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Influence of damage caused by Kr ions and neutrons on electrical properties of silicon detectors

International Nuclear Information System (INIS)

Croitoru, N.; Gubbini, E.; Rancoita, P.G.; Rattaggi, M.; Seidman, A.

1999-01-01

In this paper, new measurements of physical properties of high-resistivity silicon, used in high-energy detectors, are presented. The obtained data contribute to the understanding of the causes which damage the 2electronic characteristics of the detection systems under irradiation of neutrons and ionized particles (Kr). The Hall effect coefficient (R H ) and resistivity (ρ) measurements as a function of temperature (T), for non-irradiated and irradiated by neutrons and Kr ions, were performed. The measurements of the Hall coefficient and resistivity of non-irradiated samples and irradiated at neutron fluences (PHI≤9.9x10 10 n/cm 2 ) and Kr (PHI≤7.5x10 8 Kr/cm 2 ), have shown that the obtained characteristics, R H (T) and ρ(T), are of the same shape as those known for a silicon single crystal. A slight difference of the slope of ln ρ∼ln T, for neutron- and a large difference for Kr ion irradiation as compared with that of non-irradiated samples, was observed. On increasing the irradiation to PHI larger than the value indicated above, for neutrons and Kr ions, important changes in the physical properties were observed. The resistivity increases with increasing PHI, up to a value of the same order with intrinsic silicon (ρ∼10 5 Ω cm), for both neutron and Kr ion irradiation. The values of R H increase with increasing PHI up to a fluence, for which a change of sign, from negative to positive, occurs. The variation of values of R H and ρ as a function of PHI, for neutrons and Kr ions, is similar, but the characteristics R H (PHI) and ρ(PHI), are displaced. Therefore, larger values of PHI are needed in order to obtain the same values of ρ as those for Kr ion irradiation. The dependence on T of electrical parameters of samples, irradiated at PHI≥9.9x10 10 n/cm 2 (neutrons) and PHI≥7.5x10 8 Kr/cm 3 (ions), cannot be explained, considering the usual theoretical relations. The results, obtained in these experiments, have shown a change of mechanism of

Application of Faraday cup array detector in measurement of electron-beam distribution homogeneity

International Nuclear Information System (INIS)

Xu Zhiguo; Wang Jinchuan; Xiao Guoqing; Guo Zhongyan; Wu Lijie; Mao Ruishi; Zhang Li

2005-01-01

It is described that a kind of Faraday cup array detector, which consists of Faraday cup, suppressor electrode insulation PCB board, Base etc. The homogeneity of electron-beam distribution is measured and the absorbed dose for the irradiated sample is calculated. The results above provide the important parameters for the irradiation experiment and the improvement for the quality of electron beam. (authors)

Evaluation of the dark signal performance of different SiPM-technologies under irradiation with cold neutrons

Energy Technology Data Exchange (ETDEWEB)

Durini, Daniel, E-mail: d.durini@fz-juelich.de [Central Institute of Engineering, Electronics and Analytics ZEA-2 – Electronic Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Degenhardt, Carsten; Rongen, Heinz [Central Institute of Engineering, Electronics and Analytics ZEA-2 – Electronic Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Feoktystov, Artem [Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, D-85748 Garching (Germany); Schlösser, Mario; Palomino-Razo, Alejandro [Central Institute of Engineering, Electronics and Analytics ZEA-2 – Electronic Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Frielinghaus, Henrich [Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, D-85748 Garching (Germany); Waasen, Stefan van [Central Institute of Engineering, Electronics and Analytics ZEA-2 – Electronic Systems, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany)

2016-11-01

In this paper we report the results of the assessment of changes in the dark signal delivered by three silicon photomultiplier (SiPM) detector arrays, fabricated by three different manufacturers, when irradiated with cold neutrons (wavelength λ{sub n}=5 Å or neutron energy of E{sub n}=3.27 meV) up to a neutron dose of 6×10{sup 12} n/cm{sup 2}. The dark signals as well as the breakdown voltages (V{sub br}) of the SiPM detectors were monitored during the irradiation. The system was characterized at room temperature. The analog SiPM detectors, with and without a 1 mm thick Cerium doped {sup 6}Li-glass scintillator material located in front of them, were operated using a bias voltage recommended by the respective manufacturer for a proper detector performance. I{sub out}-V{sub bias} measurements, used to determine the breakdown voltage of the devices, were repeated every 30 s during the first hour and every 300 s during the rest of the irradiation time. The digital SiPM detectors were held at the advised bias voltage between the respective breakdown voltage and dark count mappings repeated every 4 min. The measurements were performed on the KWS-1 instrument of the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching, Germany. The two analog and one digital SiPM detector modules under investigation were respectively fabricated by SensL (Ireland), Hamamatsu Photonics (Japan), and Philips Digital Photon Counting (Germany).

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...

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

First results on irradiation of ceramic parallel plate chambers with gammas and neutrons

International Nuclear Information System (INIS)

Arefiev, A.; Bencze, Gy.L.; Bizzeti, A.; Choumilov, E.; Civinini, C.; Dajko, G.; D'Alessandro, R.; Fenyvesi, A.; Ferrando, A.; Fouz, M.C.; Iglesias, A.; Ivochkin, V.; Josa, M.I.; Malinin, A.; Meschini, M.; Molnar, J.; Pojidaev, V.; Salicio, J.M.; Tanko, L.; Vesztergombi, G.

1996-01-01

Ceramic parallel plate chambers were irradiated with gamma rays and neutrons. Results on radiation resistance are presented after 60 Mrad gamma and 0.5.10 16 neutrons per cm 2 irradiation of the detector surface. Results of activation analysis of chambers made of two different ceramic materials are also presented. (orig.)

Silicon detectors for the sLHC

Czech Academy of Sciences Publication Activity Database

Affolder, A.; Aleev, A.; Allport, P.P.; Böhm, Jan; Mikeštíková, Marcela; Popule, Jiří; Šícho, Petr; Tomášek, Michal; Vrba, Václav

2011-01-01

Roč. 658, č. 1 (2011), s. 11-16 ISSN 0168-9002 R&D Projects: GA MŠk LA08032; GA ČR GA202/05/0653; GA MŠk 1P04LA212 Institutional research plan: CEZ:AV0Z10100502 Keywords : silicon particle detectors * radiation damage * irradiation * charge collection efficiency Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.207, year: 2011

Front-side biasing of n-in-p silicon strip detectors

CERN Document Server

Baselga Bacardit, Marta; Dierlamm, Alexander Hermann; Dragicevic, Marko Gerhart; Konig, Axel; Pree, Elias; Metzler, Marius

2018-01-01

Front-side biasing is an alternative method to bias a silicon sensor. Instead of directly applying high voltage to the back-side, one can exploit the conductive properties of the edge region to bias a detector exclusively via top-side connections. This option can be beneficial for the detector design and might help to facilitate the assembly process of modules. The effective bias voltage is affected by the resistance of the edge region and the sensor current. The measurements of n-in-p sensors performed to qualify this concept have shown that the voltage drop emerging from this resistance is negligible before irradiation. After irradiation, however, the resistivity of the edge region increases with fluence and saturates in the region of 10$^{7}\\,\\Omega$ at a fluence of 1$\\,\\cdot\\,10^{15}\\,$n$_{\\textrm{eq}}$cm$^{-2}$. The measurements are complemented by TCAD simulations and interpretations of the observed effects.

Performances and ageing study of resistive-anodes Micromegas detectors for HL-LHC environment

CERN Document Server

Jeanneau, F; Attié, D; Boyer, M; Derré, J; Fanourakis, G; Ferrer-Ribas, E; Galán, J; Gazis, E; Geralis, T; Giganon, A; Giomataris, I; Herlant, S; Manjarrés, J; Ntomari, E; Schune, Ph; Titov, M; Tsipolitis, G

2012-01-01

With the tenfold luminosity increase envisaged at the HL-LHC, the background (photons, neutrons, ...) and the event pile-up probability are expected to increase in proportion in the different experiments, especially in the forward regions like, for instance, the muons chambers of the ATLAS detector. Detectors based on the Micromegas principle should be good alternatives for the detector upgrade in the HL-LHC framework because of a good spatial ( 98%) can be achieved with resistive-anode micromegas detector. An X-rays irradiation has been also performed, showing no ageing effect after more than 21 days exposure and an integrated charge of almost 1C.

Operation of a hemispherical detector for LET measurements

International Nuclear Information System (INIS)

Schell, M.C.; DeLuca, P.M. Jr.; Pearson, D.W.

1982-01-01

A hemispherical ΔE/E detector has been constructed and tested for the measurement of linear-energy-transfer distributions of charged particles induced by fast neutrons. The initial performance test results and LET distributions from 14.8-MeV monoenergetic neutron irradiation in free space of carbon, lead, and Al50-plastic are presented

UNDERWATER ANALYSIS OF IRRADIATED REACTOR SLUGS FOR Co-60 AND OTHER RADIONUCLIDES AT THE SAVANNAH RIVER SITE

International Nuclear Information System (INIS)

CASELLA, VITO

2004-01-01

Co-60 was produced in the Savannah River Site (SRS) reactors in the 1970s, and the irradiated cobalt reactor slugs were stored in a reactor basin at SRS. Since the activity rates of these slugs were not accurately known, assaying was required. A sodium iodide gamma detector was placed above a specially designed air collimator assembly, so that the slug was eight to nine feet from the detector and was shielded by the basin water. Also, 18 curium sampler slugs, used to produce Cm-244 from Pu-239, were to be disposed of with the cobalt slugs. The curium slugs were also analyzed with a High Purity Germanium (HPGE) detector in an attempt to identify any additional radionuclides produced from the irradiation. Co-60 concentrations were determined for reactor disassembly basin cobalt slugs and the 18 curium sampler slugs. The total Co-60 activity of all of the assayed slugs in this work summed to 31,783 curies on 9/15/03. From the Co-60 concentrations of the curium sampler slugs, the irradiation flux was determined for the known irradiation time. The amounts of Pu-238,-239,-240,-241,-242; Am-241,-243; and Cm-242,-244 produced were then obtained based on the original amount of Pu-239 irradiated

X-ray irradiation of yeast cells

Science.gov (United States)

Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

1997-10-01

Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

Design, characterization and beam test performance of different silicon microstrip detector geometries

International Nuclear Information System (INIS)

Catacchini, E.; Ciampolini, L.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Lenzi, M.; Meschini, M.; Parrini, G.; Pieri, M.

1998-01-01

During the last few years a large number of silicon microstrip detectors has been especially designed and tested in order to study and optimize the performances of the tracking devices to be used in the forward-backward part of the CMS (technical proposal, CERN/LHCC 94-38 LHCC/Pl, 15 December 1994) experiment. Both single and double sided silicon detectors of a trapezoidal ('wedge') shape and with different strip configurations, including prototypes produced with double metal technology, were characterized in the laboratory and tested using high-energy beams. Furthermore, due to the high-radiation environment where the detectors should operate, particular care was devoted to the study of the characteristics of heavily irradiated detectors. The main results of detector performances (charge response, signal-to-noise ratio, spatial resolution etc.) will be reviewed and discussed. (author)

Irradiation facilities at the Los Alamos Meson Physics Facility

International Nuclear Information System (INIS)

Sandberg, V.

1990-01-01

The irradiation facilities for testing SSC components and detector systems are described. Very high intensity proton, neutron, and pion fluxes are available with beam kinetic energies of up to 800 MeV. 4 refs., 12 figs., 2 tabs

Effect of electron beam irradiation on the thermal properties of polycarbonate / polyester blend

International Nuclear Information System (INIS)

Zarie, K.A.

2007-01-01

The effect of electron beam irradiation on the thermal properties of Bayfol (polycarbonate/polyester blend) solid state nuclear track detector (SSNTD) was investigated. Non-isothermal studies were carried out using thermogravimetric analysis (TGA) and differential thermogravimetric (DTG) to obtain the activation energy of thermal decomposition for Bayfol detector. The thermogravimetric analysis (TGA) indicated that the Bayfol samples were decomposed in one main break down stage. Samples of 250 μm thickness sheets were exposed to electron beam irradiations in the dose range 20-600 KGy. The variation of melting temperatures with the electron dose was determined using differential thermal analysis (DTA). The results indicated that the electron irradiation in the dose range 200-600 KGy decreases the melting temperature of the Bayfol samples and this is most suitable for applications requiring the molding of this polymer at lower temperatures

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)

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).

Calibration of new batches and a study of applications of nuclear track detectors under the harsh conditions of nuclear fusion experiments

Energy Technology Data Exchange (ETDEWEB)

Malinowska, A., E-mail: a.malinowska@ncbj.gov.pl [National Centre for Nuclear Research, Andrzeja Soltana 7 Str., 05-400 Otwock (Poland); Szydlowski, A.; Jaskola, M.; Korman, A.; Malinowski, K.; Kuk, M. [National Centre for Nuclear Research, Andrzeja Soltana 7 Str., 05-400 Otwock (Poland)

2012-06-15

Highlights: Black-Right-Pointing-Pointer Each new batch of PM-355 material should be carefully calibrated. Black-Right-Pointing-Pointer The detectors heated at a temperature higher than 100 Degree-Sign C demonstrate v nearly equal to 1. Black-Right-Pointing-Pointer The dependence of V{sub B} on the temperature is similar to the dependence of V{sub B} on the dose of electron and gamma radiation. Black-Right-Pointing-Pointer The aging effect of these materials also has a significant influence on the track diameter. - Abstract: This paper describes calibration studies of PM-355 detectors manufactured at different times in order to compare their sensitivity to the investigated ions. These studies were motivated by the application of solid-state nuclear track detectors (SSNTDs) in fusion experiments to measure energetic ions escaping from high-temperature plasmas. The CR-39 detector and its new versions such as PM-355, PM-500, PM-600 have been examined for several years at our institute. The PM-355 plastic appeared to be the best, especially for the detection of light ions. However, to use these detectors optimally, especially in spectroscopic measurements, each new batch of PM-355 material should be carefully calibrated. In high temperature plasma experiments the detectors operate under harsh conditions of high temperature, heat impact, intense X-ray, neutron and fast electron radiation. In order to evaluate the effect of these conditions on the crater formation process, some of the {alpha} particle- and proton-irradiated PM-355 detector samples were heated in an oven and then etched and scanned. Other alpha- and proton-irradiated samples were exposed to {gamma} and electron radiation of doses varying from 100 to 2000 kGy. The irradiated samples were then etched in steps and the bulk etching rate v{sub B} of the PM-355 material was determined. The craters induced by the projectiles in both heated and {gamma} and electron irradiated samples differ considerably from the

Vanadium Beta Emission Detectors for Reactor In-Core Neutron Monitoring

Energy Technology Data Exchange (ETDEWEB)

Andersson, I Oe; Soederlund, B

1969-06-15

In-core flux measurements are becoming increasingly important in both power reactors and test reactors. In particular power distribution measurements in large power reactors have to be performed with a great number of neutron detectors capable of withstanding high integrated flux values. This report presents a summary of the development and application of a new type of nuclear radiation sensor, a beta emission detector, for measurements at high neutron flux levels. The work has been carried out at the Section for Instrumentation and has been the basis for a type of neutron detector employed in the Marviken in-core system as well as for other types. The report describes the design and principle of operation, experiments and tests. Also included are the results and comments from a long-term irradiation of some detectors in the Halden reactor.

Proposal for an irradiation facility at the TAEK SANAEM Proton Accelerator Facility

Science.gov (United States)

Demirköz, B.; Gencer, A.; Kiziloren, D.; Apsimon, R.

2013-12-01

Turkish Atomic Energy Authority's (TAEK's) Proton Accelerator Facility in Ankara, Turkey, has been inaugurated in May 2012 and is under the process of being certified for commercial radio-isotope production. Three of the four arms of the 30 MeV cyclotron are being used for radio-isotope production, while the fourth is foreseen for research and development of novel ideas and methods. The cyclotron can vary the beam current between 12 μA and 1.2 mA, sufficient for irradiation tests for semiconductor materials, detectors and devices. We propose to build an irradiation facility in the R&D room of this complex, open for use to the international detector development community.

Development of the dyed-track method for Kodak CN-85 detector. No. E/3

International Nuclear Information System (INIS)

Somogyi, G.; Toth-Szilagyi, M.; Varga, Zs.; Monnin, M.; Lferde, M.

1983-01-01

The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, coloration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In the authors' previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work the influence of track processing parameters on the dyed-track formation was studied in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particles irradiation. For sensitization a treatment with 15% HCL at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be best. For understanding the track dyeing phenomenon the coloration behaviour of electron-irradiated CN-85 detectors was studied. (author)

Evaluation of activation detectors for the SPHINX project at the LR-0 experimental reactor

International Nuclear Information System (INIS)

Lahodova, Zdena; Viererbl, Ladislav; Novak, Evzen; Svadlenkova, Marie; Rypar, Vojtech

2008-01-01

This article summarizes the measurements of neutron fluence distributions carried out at the LR-0 research reactor (Czech Republic) in the frame of the SPHINX project. The influence of fluoride-salts or graphite filling in the SR-0 modules on neutron spectrum was studied using activation detectors. The activation detectors (Mn, Ni, In and Au) were evaluated to determine the changes in neutron field. The In and Au detectors were also irradiated with a cadmium cover. Five different configurations of reactor core (EROS) were realized. (authors)

Evaluation of activation detectors for the SPHINX project at the LR-0 experimental reactor

Energy Technology Data Exchange (ETDEWEB)

Lahodova, Zdena; Viererbl, Ladislav [Research Center Rez Ltd (Czech Republic); Novak, Evzen; Svadlenkova, Marie; Rypar, Vojtech [Nuclear Power and Safety Division, Nuclear Research Institute Rez plc (Czech Republic)

2008-07-01

This article summarizes the measurements of neutron fluence distributions carried out at the LR-0 research reactor (Czech Republic) in the frame of the SPHINX project. The influence of fluoride-salts or graphite filling in the SR-0 modules on neutron spectrum was studied using activation detectors. The activation detectors (Mn, Ni, In and Au) were evaluated to determine the changes in neutron field. The In and Au detectors were also irradiated with a cadmium cover. Five different configurations of reactor core (EROS) were realized. (authors)

Characterization of nanoDot optically stimulated luminescence detectors and high-sensitivity MCP-N thermoluminescent detectors in the 40-300 kVp energy range.

Science.gov (United States)

Poirier, Yannick; Kuznetsova, Svetlana; Villarreal-Barajas, Jose Eduardo

2018-01-01

To investigate empirically the energy dependence of the detector response of two in vivo luminescence detectors, LiF:Mg,Cu,P (MCP-N) high-sensitivity TLDs and Al 2 O 3 :C OSLDs, in the 40-300-kVp energy range in the context of in vivo surface dose measurement. As these detectors become more prevalent in clinical and preclinical in vivo measurements, knowledge of the variation in the empirical dependence of the measured response of these detectors across a wide spectrum of beam qualities is important. We characterized a large range of beam qualities of three different kilovoltage x-ray units: an Xstrahl 300 Orthovoltage unit, a Precision x-Ray X-RAD 320ix biological irradiator, and a Varian On-Board Imaging x-ray unit. The dose to water was measured in air according to the AAPM's Task Group 61 protocol. The OSLDs and TLDs were irradiated under reference conditions on the surface of a water phantom to provide full backscatter conditions. To assess the change in sensitivity in the long term, we separated the in vivo dosimeters of each type into an experimental and a reference group. The experimental dosimeters were irradiated using the kilovoltage x-ray units at each beam quality used in this investigation, while the reference group received a constant 10 cGy irradiation at 6 MV from a Varian clinical linear accelerator. The individual calibration of each detector was verified in cycles where both groups received a 10 cGy irradiation at 6 MV. The nanoDot OSLDs were highly reproducible, with ±1.5% variation in response following >40 measurement cycles. The TLDs lost ~20% of their signal sensitivity over the course of the study. The relative light output per unit dose to water of the MCP-N TLDs did not vary with beam quality for beam qualities with effective energies <50 keV (~150 kVp/6 mm Al). At higher energies, they showed a reduced (~75-85%) light output per unit dose relative to 6 MV x rays. The nanoDot OSLDs exhibited a very strong (120

Facilities for studying radiation damage in nonmetals during irradiation

International Nuclear Information System (INIS)

Levy, P.W.

1984-08-01

Two facilities have been developed for making optical absorption, luminescence and other measurements on a single sample before, during and after irradiation. One facility uses 60 Co gamma rays and the other 0.5 to 3 MeV electrons from an accelerator. Optical relays function as spectrophotometers, luminescenc detectors, etc. All radiation sensitive components are outside of walk-in irradiation chambers; all measurement control and data recording is computerized. Irradiations are made at controlled temperatures between 5K and 900 0 C. The materials studied include glasses, quartz, alkali halides (especially natural rock salt), organic crystals, etc. As determined from color center measurements the damage formation rate in all materials studied at 25 0 C or above is strongly temperature dependent. The defect concentration during irradiation is usually much greater than that measured after irradiation. The fraction of defects annealing after irradiation and the annealing rate usually increases as the irradiation temperature increases. The completed studies demonstrate that, in most cases, the extent of maximum damage and the damage formation and annealing kinetics can be determined only by making measurements during irradiation

Assessment of population external irradiation doses with consideration of Rospotrebnadzor bodies equipment for monitoring of photon radiation dose

Directory of Open Access Journals (Sweden)

I. P. Stamat

2016-01-01

Full Text Available This paper provides review of equipment and methodology for measurement of photon radiation dose; analysis of possible reasons for considerable deviation between the Russian Federation population annual effective external irradiation doses and the relevant average global value. Data on Rospotrebnadzor bodies dosimetry equipment used for measurement of gamma radiation dose are collected and systematized. Over 60 kinds of dosimeters are used for monitoring of population external irradiation doses. Most of dosimeters used in the country have gas-discharge detectors (Geiger-Mueller counters, minor biochemical annunciators, etc. which have higher total values of own background level and of space radiation response than the modern dosimeters with scintillation detectors. This feature of dosimeters is apparently one of most plausible reasons of a bit overstating assessment of population external irradiation doses. The options for specification of population external irradiation doses assessment are: correction of gamma radiation dose measurement results with consideration of dosimeters own background level and space radiation response, introduction of more up-to-date dosimeters with scintillation detectors, etc. The most promising direction of research in verification of population external irradiation doses assessment is account of dosimetry equipment.

Determination of o-tyrosine in irradiated chicken

International Nuclear Information System (INIS)

Zoller, O.; Schoeni, D.; Zimmerli, B.

1991-01-01

The author explains his method to determine O-Tyrosine in irradiated chickens with a high-performance liquid chromatography. The method is simple and fast, but a proper chromatographic separation is difficult. The detection limit with a high sensitive detector is about 0.05-0.1 mg O-Tyrosine/kg meat (9 refs)

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

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

Projection of the annealing behavior of irradiated Si sensors in the LHC environment

CERN Document Server

Chatterji, S; Bhardwaj, N; Chauhan, S S; Choudhary, B C; Gupta, P; Jha, M; Kumar, A; Naimuddin, M; Ranjan, K; Shivpuri, R K; Srivastava-Ajay, K

2004-01-01

The study of the radiation tolerance and subsequent annealing effects on p+-n-n+ silicon micro strip detectors has been performed as a part of R&D program for the preshower detector in the CMS experiment. CMS silicon strip sensors were irradiated with 24 GeV protons at CERN proton synchrotron (PS) to a total fluence of 3*10/sup 14/ p/cm/sup 2 /. Sensors were stored in freezer after irradiation and I-V and C-V measurements were carried out. Variation in full depletion voltage and leakage current have been studied as a function of annealing time. The breakdown performance of the device actually improves after irradiation due to the beneficial effect of type-inversion. The breakdown voltage increases further with annealing time. However, the leakage current increases tremendously just after irradiation. As the sensors are annealed, there is a drop in leakage current. The rate of annealing is observed to be temperature dependent. Hence in terms of leakage current, it seems that room temperature annealing is b...

Silicon strip detector for a novel 2D dosimetric method for radiotherapy treatment verification

Science.gov (United States)

Bocci, A.; Cortés-Giraldo, M. A.; Gallardo, M. I.; Espino, J. M.; Arráns, R.; Alvarez, M. A. G.; Abou-Haïdar, Z.; Quesada, J. M.; Pérez Vega-Leal, A.; Pérez Nieto, F. J.

2012-05-01

The aim of this work is to characterize a silicon strip detector and its associated data acquisition system, based on discrete electronics, to obtain in a near future absorbed dose maps in axial planes for complex radiotherapy treatments, using a novel technique. The experimental setup is based on two phantom prototypes: the first one is a polyethylene slab phantom used to characterize the detector in terms of linearity, percent depth dose, reproducibility, uniformity and penumbra. The second one is a cylindrical phantom, specifically designed and built to recreate conditions close to those normally found in clinical environments, for treatment planning assessment. This system has been used to study the dosimetric response of the detector, in the axial plane of the phantom, as a function of its angle with respect to the irradiation beam. A software has been developed to operate the rotation of this phantom and to acquire signals from the silicon strip detector. As an innovation, the detector was positioned inside the cylindrical phantom parallel to the beam axis. Irradiation experiments were carried out with a Siemens PRIMUS linac operating in the 6 MV photon mode at the Virgen Macarena Hospital. Monte Carlo simulations were performed using Geant4 toolkit and results were compared to Treatment Planning System (TPS) calculations for the absorbed dose-to-water case. Geant4 simulations were used to estimate the sensitivity of the detector in different experimental configurations, in relation to the absorbed dose in each strip. A final calibration of the detector in this clinical setup was obtained by comparing experimental data with TPS calculations.

Silicon strip detectors for the ATLAS upgrade

CERN Document Server

Gonzalez Sevilla, S; The ATLAS collaboration

2011-01-01

The Large Hadron Collider at CERN will extend its current physics program by increasing the peak luminosity by one order of magnitude. For ATLAS, one of the two general-purpose experiments of the LHC, an upgrade scenario will imply the complete replacement of its internal tracker due to the harsh conditions in terms of particle rates and radiation doses. New radiation-hard prototype n-in-p silicon sensors have been produced for the short-strip region of the future ATLAS tracker. The sensors have been irradiated up to the fluences expected in the high-luminous LHC collider. This paper summarizes recent results on the performance of the irradiated n-in-p detectors.

TU-H-CAMPUS-TeP2-03: High Sensitivity and High Resolution Fiber Based Micro-Detector for Sub-Millimeter Preclinical Dosimetry

International Nuclear Information System (INIS)

Izaguirre, E; Pokhrel, S; Knewtson, T; Hedrick, S

2016-01-01

Purpose: Current precision of small animal and cell micro-irradiators has continuously increased during the past years. Currently, preclinical irradiators can deliver sub-millimeter fields with micrometric precision but there are no water equivalent dosimeters to determine small field profiles and dose in the orthovoltage range of energies with micrometric resolution and precision. We have developed a fiber based micro-dosimeter with the resolution and dosimetric accuracy required for radiobiological research. Methods: We constructed two prototypes of micro-dosimeters based on different compositions of fiber scintillators to study the spatial resolution and dosimetric precision of small animal and cell micro-irradiators. The first has green output and the second has blue output. The blue output dosimeter has the highest sensitivity because it matches the spectral sensitivity of silicon photomultipliers. A blue detector with 500um cross section was built and tested respect to a CC01 ion chamber, film, and the 1500um green output detector. Orthovoltage fields from 1×1mm2 to 5×5mm2 were used for detector characteristics comparison. Results: The blue fiber dosimeter shows great agreement with films and matches dose measurements with the gold-standard ion chamber for 5×5mm2 fields. The detector has the appropriate sensitivity to measure fields from 1×1mm2 to larger sizes with a 1% dosimetric accuracy. The spatial resolution is in the sub-millimeter range and the spectral matching with the photomultiplier allows reducing the sensor cross section even further than the presented prototype. These results suggest that scintillating fibers combined with silicon photomultipliers is the appropriate technology to pursue micro-dosimetry for small animals and disperse cell samples. Conclusion: The constructed detectors establish a new landmark for the resolution and sensitivity of fiber based microdetectors. The validation of the detector in our small animal and cell

Charged particle discrimination with silicon surface barrier detectors

International Nuclear Information System (INIS)

Coote, G.E.; Pithie, J.; Vickridge, I.C.

1996-01-01

The application for materials analysis of nuclear reactions that give rise to charged particles is a powerful surface analytical and concentration depth profiling technique. Spectra of charged particles, with energies in the range 0.1 to 15 MeV, emitted from materials irradiated with beams of light nuclei such as deuterons are measured with silicon surface barrier detectors. The spectra from multi-elemental materials typically encountered in materials research are usually composed of an overlapping superposition of proton, alpha, and other charged particle spectra. Interpretation of such complex spectra would be simplified if a means were available to electronically discriminate between the detector response to the different kinds of charged particle. We have investigated two methods of discriminating between different types of charged particles. The fast charge pulses from a surface barrier detector have different shapes, depending on the spatial distribution of energy deposition of the incident particle. Fast digitisation of the pulses, followed by digital signal processing provides one avenue for discrimination. A second approach is to use a thin transmission detector in front of a thick detector as a detector telescope. For a given incident energy, different types of charged particles will lose different amounts of energy in the thin detector, providing an alternative means of discrimination. We show that both approaches can provide significant simplification in the interpretation of charged particle spectra in practical situations, and suggest that silicon surface barrier detectors having graded electronic properties could provide improved discrimination compared to the current generation of detectors having homogeneous electronic properties. (author).12 refs., 2 tabs., 28 figs

Charge losses in silicon sensors and electric-field studies at the Si-SiO2 interface

International Nuclear Information System (INIS)

Poehlsen, Thomas

2013-07-01

accumulation layer and when the accumulation layer returns to steady state is investigated. Irradiated silicon pad sensors are used to study the charge-collection efficiency (CCE) of charge carriers generated using laser light of 1063 nm wavelength, as a function of bulk material, active sensor thickness, voltage, temperature, particle type (for the irradiation) and fluence. As a cross check the CCE is also determined for charge carriers generated by electrons from a 90 Sr-source. A precision of 3 % in the CCE is achieved. Sensors of n-doped and p-doped silicon are compared, as well as sensors of different crystal-growing methods (magnetic Czochralski (MCz) and float zone (FZ)). The sensor thickness varies from 200 μm (MCz and FZ) to 320 μm (FZ). The 320 μm thick FZ sensors underwent a dopant-diffusion process (dd-FZ) to reduce the active sensor thickness. For the irradiation both protons of different energies (23 MeV and 23 GeV) and reactor neutrons (∝1 MeV) are used. The achieved fluences are between 3.10 14 cm -2 and 1.3.10 16 cm -2 1 MeV-neutron equivalent. The CCE is used to calculate the signal corresponding to a minimum-ionising particle (mip) traversing the sensor and to calculate the effective distance the generated charge carriers drift. While little difference in CCE between the 200 m thick MCz and FZ materials is found, the dd-FZ materials of both ∝200 μm and ∝300 μm active thickness have a lower CCE, corresponding also to a shorter effective drift distance. The CCE and the effective drift distance are also calculated for eh pairs generated close to the sensor surface using laser light of 660 nm wavelength. The measurements are not compatible with a position-independent trapping probability, and qualitative agreement with a position-dependent occupation of radiation-induced trapping centres due to the dark current is found.

Charge losses in silicon sensors and electric-field studies at the Si-SiO{sub 2} interface

Energy Technology Data Exchange (ETDEWEB)

Poehlsen, Thomas

2013-07-15

added to the accumulation layer and when the accumulation layer returns to steady state is investigated. Irradiated silicon pad sensors are used to study the charge-collection efficiency (CCE) of charge carriers generated using laser light of 1063 nm wavelength, as a function of bulk material, active sensor thickness, voltage, temperature, particle type (for the irradiation) and fluence. As a cross check the CCE is also determined for charge carriers generated by electrons from a {sup 90}Sr-source. A precision of 3 % in the CCE is achieved. Sensors of n-doped and p-doped silicon are compared, as well as sensors of different crystal-growing methods (magnetic Czochralski (MCz) and float zone (FZ)). The sensor thickness varies from 200 {mu}m (MCz and FZ) to 320 {mu}m (FZ). The 320 {mu}m thick FZ sensors underwent a dopant-diffusion process (dd-FZ) to reduce the active sensor thickness. For the irradiation both protons of different energies (23 MeV and 23 GeV) and reactor neutrons ({proportional_to}1 MeV) are used. The achieved fluences are between 3.10{sup 14} cm{sup -2} and 1.3.10{sup 16} cm{sup -2} 1 MeV-neutron equivalent. The CCE is used to calculate the signal corresponding to a minimum-ionising particle (mip) traversing the sensor and to calculate the effective distance the generated charge carriers drift. While little difference in CCE between the 200 m thick MCz and FZ materials is found, the dd-FZ materials of both {proportional_to}200 {mu}m and {proportional_to}300 {mu}m active thickness have a lower CCE, corresponding also to a shorter effective drift distance. The CCE and the effective drift distance are also calculated for eh pairs generated close to the sensor surface using laser light of 660 nm wavelength. The measurements are not compatible with a position-independent trapping probability, and qualitative agreement with a position-dependent occupation of radiation-induced trapping centres due to the dark current is found.

Pixel Detector Developments for Tracker Upgrades of the High Luminosity LHC

CERN Document Server

Meschini, Marco; Dalla Betta, G. F; Dinardo, Mauro; Giacomini, G; Menasce, Dario; Mendicino, R; Messineo, Alberto; Moroni, Luigi; Ronchin, S; Sultan, D.M.S; Uplegger, Lorenzo; Viliani, Lorenzo; Zoi, Irene; Zuolo, Davide

2017-01-01

and 3D devices. The results on the 3D pixel sensors before irradiation are very satisfactory and % make us confident support the conclusion that columnar devices are % 3D devices very good candidates for the inner layers of the upgrade pixel detectors.

Measurements of possible type inversion in silicon junction detectors by fast neutron irradiation

International Nuclear Information System (INIS)

Li, Z.; Kraner, H.W.

1991-05-01

The successful application of silicon position sensitive detectors in experiments at the SSC or LHC depends on an accurate assessment of the radiation tolerance of this detector species. In particular, fast neutrons (E av = 1 MeV) produce bulk displacement damage that is projected, from estimated fluences, to cause increased generation (leakage) current, charge collection deficiencies, resistivity changes and possibly semiconductor type change or inversion. Whereas the leakage current increase was believed to be the major concern for estimated fluences of 10 12 n/cm 2 experiment year at the initial SSC luminosity of 10 33 /cm 2 -sec, increased luminosity and exposure time has raised the possible exposure to 10 14 n/cm 2 , which opens the door for the several other radiation effects suggested above to play observable and significant roles in detector degradation or change. 17 refs., 19 figs

Silicon microstrip detectors on 6'' technology

CERN Document Server

Bölla, G; Günther, M; Martignon, G; Bacchetta, N; Bisello, D; Leonardi, G L; Lucas, T; Wilburn, C

1999-01-01

The fabrication of microstrip detectors on 4'' high-resistivity wafers that allow for a maximum workable area of about 42 cm sup 2 has been well established. Using 6'' wafers the workable area increases up to 100 cm sup 2 (more than twice the area of a 4'' wafer) allowing a larger number of detectors to be processed at the same time on the same wafer resulting in a sizable reduction of cost. After a prototyping stage, the CDF silicon tracker upgrade is now receiving final production sensors from Micron Semiconductor Ltd. The performance of double-sided single-metal small stereo angle sensors for the CDF SVXII and ISL detectors has been studied. Results include probe station measurements and test beam results. The problems encountered from prototyping to the final devices are described. A brief overview of the response of the sensors to irradiation with gamma-rays and p sup + up to a dose of 0.5 Mrad (well above the doses expected during Run II of the Tevatron) is included. (author)

SiC-based neutron detector in quasi-realistic working conditions: efficiency and stability at room and high temperature under fast neutron irradiations

Energy Technology Data Exchange (ETDEWEB)

Ferone, Raffaello; Issa, Fatima; Ottaviani, Laurent; Biondo, Stephane; Vervisch, Vanessa [IM2NP, UMR CNRS 7334, Aix-Marseille University, Case 231,13397 Marseille Cedex 20, (France); Szalkai, Dora; Klix, Axel [KIT- Karlsruhe Institute of Technology, Institute of Neutron Physics and Reactor Technology Karlsruhe 76344, (Germany); Vermeeren, Ludo [SCK-CEN, Boeretang 200, B-2400 Mol, (Belgium); Saenger, Richard [Schlumberger, Clamart, (France); Lyoussi, Abadallah [CEA, DEN, Departement d' Etudes des Reacteurs, Service de Physique Experimentale, Laboratoire Dosimetrie Capteurs Instrumentation, 13108 Saint-Paul-lez-Durance, (France)

2015-07-01

In the framework of the European I SMART project, we have designed and made new SiC-based nuclear radiation detectors able to operate in harsh environments and to detect both fast and thermal neutrons. In this paper, we report experimental results of fast neutron irradiation campaign at high temperature (106 deg. C) in quasi-realistic working conditions. Our device does not suffer from high temperature, and spectra do show strong stability, preserving features. These experiments, as well as others in progress, show the I SMART SiC-based device skills to operate in harsh environments, whereas other materials would strongly suffer from degradation. Work is still demanded to test our device at higher temperatures and to enhance efficiency in order to make our device fully exploitable from an industrial point of view. (authors)

Characterization of saturation of CR-39 detector at high alpha-particle fluence

Directory of Open Access Journals (Sweden)

M. El Ghazaly

2018-04-01

Full Text Available The occurrence of saturation in the CR-39 detector reduces and limits its detection dynamic range; nevertheless, this range could be extended using spectroscopic techniques and by measuring the net bulk rate of the saturated CR-39 detector surface. CR-39 detectors were irradiated by 1.5 MeV high alpha-particle fluence varying from 0.06 × 108 to 7.36 × 108 alphas/cm2 from Am-241 source; thereafter, they were etched in a 6.25N NaOH solution at a temperature of 70°C for different durations. Net bulk etch rate measurement of the 1.5 MeV alpha-irradiated CR-39 detector surface revealed that rate increases with increasing etching time and reaches its maximum value at the end of the alpha-particle range. It is also correlated with the alpha-particle fluence. The measurements of UV–Visible (UV–Vis absorbance at 500 and 600 nm reveal that the absorbance is linearly correlated with the fluence of alpha particles at the etching times of 2 and 4 hour. For extended etching times of 6, 10, and 14.5 hour, the absorbance is saturated for fluence values of 4.05 × 108, 5.30 × 108, and 7.36 × 108 alphas/cm2. These new methods pave the way to extend the dynamic range of polymer-based solid state nuclear track detectors (SSNTDs in measurement of high fluence of heavy ions as well as in radiation dosimetry. Keywords: Alpha Particle, Bulk Etch Rate, CR-39 Detector, Saturated Regime, UV–Vis Spectroscopy

Monitoring of the Irradiated Neutron Fluence in the Neutron Transmutation Doping Process of Hanaro

Science.gov (United States)

Kim, Myong-Seop; Park, Sang-Jun

2009-08-01

Neutron transmutation doping (NTD) for silicon is a process of the creation of phosphorus impurities in intrinsic or extrinsic silicon by neutron irradiation to obtain silicon semiconductors with extremely uniform dopant distribution. HANARO has two vertical holes for the NTD, and the irradiation for 5 and 6 inch silicon ingots has been going on at one hole. In order to achieve the accurate neutron fluence corresponding to the target resistivity, the real time neutron flux is monitored by self-powered neutron detectors. After irradiation, the total irradiation fluence is confirmed by measuring the absolute activity of activation detectors. In this work, a neutron fluence monitoring method using zirconium foils with the mass of 10 ~ 50 mg was applied to the NTD process of HANARO. We determined the proportional constant of the relationship between the resistivity of the irradiated silicon and the neutron fluence determined by using zirconium foils. The determined constant for the initially n-type silicon was 3.126 × 1019 n·Ω/cm. It was confirmed that the difference between this empirical value and the theoretical one was only 0.5%. Conclusively, the practical methodology to perform the neutron transmutation doping of silicon was established.

Response of CR-39 Detector Against Fast Neutron Using D-Polyethylene and H-Polyethylene Radiator

International Nuclear Information System (INIS)

Sofyan, Hasnel

1996-01-01

The research on the response of detector CR-39 by using D-Polyethylene and H-Polyethylene radiator has been carried out. The optimum number of nuclear tracks was found with the use of 30 % NaOH at 80 + 0,5oC for 80 minutes of etching time. The comparison of CR-39 detector response caused by D-Polyethylene radiator against H-Polyethylene radiator of irradiation in air, were found to be 1.18 and 0.84 for 241Am-Be neutron source and neutron source from reactor respectively. For phantom irradiation, the results were found to be 1.75 for 241Am-Be neutron source, and 0.77 for neutron source from reactor

The Siegen automatic measuring system for nuclear track detectors: new developments

International Nuclear Information System (INIS)

Noll, A.; Rusch, G.; Roecher, H.; Dreute, J.; Heinrich, W.

1988-01-01

Starting ten years ago we developed completely automatic scanning and measuring systems for nuclear track detectors. In this paper we describe some new developments. Our autofocus systems based on the contrast of the video picture and on a laser autofocus have been improved in speed and in reliability. Based on new algorithms, faster programs have been developed to scan for nuclear tracks in plastic detectors. Methods for separation of overlapping tracks have been improved. Interactive programs for track measurements have been developed which are very helpful for space bio-physics experiments. Finally new methods for track measurements in nuclear emulsions irradiated with a beam perpendicular to the detector surface are described in this paper. (author)

In-reactor testing of self-powered neutron detectors and miniature fission chambers

International Nuclear Information System (INIS)

Duchene, J.; LeMeur, R.; Verdant, R.

1975-01-01

The CEA has tested a variety of ''slow'' self-powered neutron detectors with rhodium, silver and vanadium emitters. Currently there are 120 vanadium detectors in the EL4 heavy water reactor. In addition, ''fast'' detectors with cobalt emitters have been tested at Saclay and 50 of these are in reactor. Other studies are concerned with 6 mm diameter miniature fission chambers. Two fast response chambers with argon-nitrogen filling gas became slow during irradiation, but operated to 600 deg C. An argon filled chamber of 4.7 mm diameter, for traversing in core system in pressurized water reactor, has shown satisfactory test results. (author)

Quantitative measurements of oxidative stress in mouse skin induced by X-ray irradiation

International Nuclear Information System (INIS)

Chi, Cuiping; Tanaka, Ryoko; Okuda, Yohei; Ikota, Nobuo; Ozawa, Toshihiko; Anzai, Kazunori; Yamamoto, Haruhiko; Urano, Shiro

2005-01-01

To find efficient methods to evaluate oxidative stress in mouse skin caused by X-ray irradiation, several markers and methodologies were examined. Hairless mice were irradiated with 50 Gy X-rays and skin homogenates or skin strips were prepared. Lipid peroxidation was measured using the skin homogenate as the level of thiobarbituric acid reactive substances. The level of lipid peroxidation increased with time after irradiation and was twice that of the control at 78 h. Electron spin resonance (ESR) spectra of skin strips showed a clear signal for the ascorbyl radical, which increased with time after irradiation in a manner similar to that of lipid peroxidation. To measure levels of glutathione (GSH) and its oxidized forms (GSSG) simultaneously, two high performance liquid chromatography (HPLC) methods, sample derivatization with 1-fluoro-2,4-dinitrobenzene and detection with a UV detector (method A) and no derivatization and detection with an electrochemical detector (method B), were compared and the latter was found to be better. No significant change was observed within 24 h after irradiation in the levels of GSH and GSSG measured by method B. The GSH/GSSG ratio may be a less sensitive parameter for the evaluation of acute oxidative stress caused by X-ray irradiation in the skin. Monitoring the ascorbyl radical seems to be a good way to evaluate oxidative stress in skin in vivo. (author)

Study of the effects of neutron irradiation on silicon strip detectors

International Nuclear Information System (INIS)

Giubellino, P.; Panizza, G.; Hall, G.; Sotthibandhu, S.; Ziock, H.J.; Ferguson, P.; Sommer, W.F.; Edwards, M.; Cartiglia, N.; Hubbard, B.; Leslie, J.; Pitzl, D.; O'Shaughnessy, K.; Rowe, W.; Sadrozinski, H.F.W.; Seiden, A.; Spencer, E.

1992-01-01

Silicon strip detectors and test structures were exposed to neutron fluences up to Φ=6.1x10 14 n/cm 2 , using the ISIS neutron source at the Rutherford Appleton Laboratory (UK). In this paper we report some of our results concerning the effects of displacement damage, with a comparison of devices made of silicon of different resistivity. The various samples exposed showed a very similar dependence of the leakage current on the fluence received. We studied the change of effective doping concentration, and observed a behaviour suggesting the onset of type inversion at a fluence of ∝2.0x10 13 n/cm 2 , a value which depends on the initial doping concentration. The linear increase of the depletion voltage for fluences higher than the inversion point could eventually determine the maximum fluence tolerable by silicon detectors. (orig.)

Nuclear radiation detector based on ion implanted p-n junction in 4H-SiC

International Nuclear Information System (INIS)

Vervisch, V.; Issa, F.; Ottaviani, L.; Lazar, M.; Kuznetsov, A.; Szalkai, D.; Klix, A.; Lyoussi, A.; Vermeeren, L.; Hallen, A.

2013-06-01

In this paper, we propose a new device detector based on ion implanted p-n junction in 4H-SiC for nuclear instrumentation. We showed the interest to use 10 Boron as a Neutron Converter Layer in order to detect thermal neutrons. We present the main results obtained during irradiation tests performed in the Belgian Reactor 1. We show the capability of our detector by means of first results of the detector response at different reverse voltage biases and at different reactor power (authors)

Diallyl phthalate (DAP) solid state nuclear track detector

CERN Document Server

Koguchi, Y; Ashida, T; Tsuruta, T

2003-01-01

Diallyl phthalate (DAP) solid state nuclear track detector is suitable for detecting heavy ions such as fission fragments, because it is insensitive to right ions such as alpha particles and protons. Detection efficiency of fission tracks is about 100%, which is unaffected under conditions below 240degC lasting for 1h or below 1 MGy of gamma-ray irradiation. Optimum etching condition for the DAP detector for detection of fission fragments is 2-4 h using 30% KOH aqueous solution at 90degC or 8-15 min using PEW-65 solution at 60degC. DAP detector is useful in detecting induced fission tracks for dating of geology or measuring intense heavy ions induced by ultra laser plasma. The fabrication of copolymers of DAP and CR-39 makes it possible to control the discrimination level for detection threshold of heavy ions. (author)

Gamma-irradiation effects on optical properties of lexan film. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Abd-Elrehim, N; El-Samahy, A E; Kassem, M E [Physics Department, Faculty of Science, Alexandria University. (Egypt); Abou-Taleb, W M [Physics and Chemistry Department, Faculty of Education, Alexandria University. (Egypt)

1996-03-01

The optical absorption method is a powerful tool for studying the optically induced transitions and for determining the energy gap in crystalline and non-crystalline materials. The absorption spectra in the lower energy part sheds light on the atomic vibrations. While the higher energy parts of the spectrum manifest the electronic states in the atoms. Effect of gamma-irradiation on the optical properties of plastic detector (Lexan film) has been studied. These investigations were carried out for gamma-doses from 10 kGy -2 mGy to determine the optical parameters; optical energy gap E{sub op}, absorption coefficient {alpha} , absorption index K, mobility energy gap E{sub g}, absorption band edge {lambda}{sub g} and the absorbance at wavelength 340 nm. The results showed that both direct and indirect transitions existed in lexan detector, and because highly sensitive to gamma-irradiation doses. The variations of optical energy gap with gamma-irradiation doses can be explained as the change in the degree of disorder and the phonon energy E{sub p}, is dose dependent. 7 figs.

Gamma-irradiation effects on optical properties of lexan film. Vol. 2

International Nuclear Information System (INIS)

Abd-Elrehim, N.; El-Samahy, A.E.; Kassem, M.E.; Abou-Taleb, W.M.

1996-01-01

The optical absorption method is a powerful tool for studying the optically induced transitions and for determining the energy gap in crystalline and non-crystalline materials. The absorption spectra in the lower energy part sheds light on the atomic vibrations. While the higher energy parts of the spectrum manifest the electronic states in the atoms. Effect of gamma-irradiation on the optical properties of plastic detector (Lexan film) has been studied. These investigations were carried out for gamma-doses from 10 kGy -2 mGy to determine the optical parameters; optical energy gap E op , absorption coefficient α , absorption index K, mobility energy gap E g , absorption band edge λ g and the absorbance at wavelength 340 nm. The results showed that both direct and indirect transitions existed in lexan detector, and because highly sensitive to gamma-irradiation doses. The variations of optical energy gap with gamma-irradiation doses can be explained as the change in the degree of disorder and the phonon energy E p , is dose dependent. 7 figs

Diamond detector in absorbed dose measurements in high-energy linear accelerator photon and electron beams.

Science.gov (United States)

Ravichandran, Ramamoorthy; Binukumar, John Pichy; Al Amri, Iqbal; Davis, Cheriyathmanjiyil Antony

2016-03-08

Diamond detectors (DD) are preferred in small field dosimetry of radiation beams because of small dose profile penumbras, better spatial resolution, and tissue-equivalent properties. We investigated a commercially available 'microdiamond' detector in realizing absorbed dose from first principles. A microdiamond detector, type TM 60019 with tandem electrometer is used to measure absorbed doses in water, nylon, and PMMA phantoms. With sensitive volume 0.004 mm3, radius 1.1mm, thickness 1 x10(-3) mm, the nominal response is 1 nC/Gy. It is assumed that the diamond detector could collect total electric charge (nC) developed during irradiation at 0 V bias. We found that dose rate effect is less than 0.7% for changing dose rate by 500 MU/min. The reproducibility in obtaining readings with diamond detector is found to be ± 0.17% (1 SD) (n = 11). The measured absorbed doses for 6 MV and 15 MV photons arrived at using mass energy absorption coefficients and stop-ping power ratios compared well with Nd, water calibrated ion chamber measured absorbed doses within 3% in water, PMMA, and nylon media. The calibration factor obtained for diamond detector confirmed response variation is due to sensitivity due to difference in manufacturing process. For electron beams, we had to apply ratio of electron densities of water to carbon. Our results qualify diamond dosimeter as a transfer standard, based on long-term stability and reproducibility. Based on micro-dimensions, we recommend these detectors for pretreatment dose verifications in small field irradiations like stereotactic treatments with image guidance.

Bolometric kinetic inductance detector technology for sub-millimeter radiometric imaging

Science.gov (United States)

Hassel, Juha; Timofeev, Andrey V.; Vesterinen, Visa; Sipola, Hannu; Helistö, Panu; Aikio, Mika; Mäyrä, Aki; Grönberg, Leif; Luukanen, Arttu

2015-10-01

Radiometric sub-millimeter imaging is a candidate technology especially in security screening applications utilizing the property of radiation in the band of 0.2 - 1.0 THz to penetrate through dielectric substances such as clothing. The challenge of the passive technology is the fact that the irradiance corresponding to the blackbody radiation is very weak in this spectral band: about two orders of magnitude below that of the infrared band. Therefore the role of the detector technology is of ultimate importance to achieve sufficient sensitivity. In this paper we present results related to our technology relying on superconducting kinetic inductance detectors operating in a thermal (bolometric) mode. The detector technology is motivated by the fact that it is naturally suitable for scalable multiplexed readout systems, and operates with relatively simple cryogenics. We will review the basic concepts of the detectors, and provide experimental figures of merit. Furthermore, we will discuss the issues related to the scale-up of our detector technology into large 2D focal plane arrays.

New results on silicon microstrip detectors of CMS tracker

International Nuclear Information System (INIS)

Demaria, N.; Albergo, S.; Angarano, M.; Azzi, P.; Babucci, E.; Bacchetta, N.; Bader, A.; Bagliesi, G.; Basti, A.; Biggeri, U.; Bilei, G.M.; Bisello, D.; Boemi, D.; Bolla, G.; Bosi, F.; Borrello, L.; Bortoletto, D.; Bozzi, C.; Braibant, S.; Breuker, H.; Bruzzi, M.; Buffini, A.; Busoni, S.; Candelori, A.; Caner, A.; Castaldi, R.; Castro, A.; Catacchini, E.; Checcucci, B.; Ciampolini, P.; Civinini, C.; Creanza, D.; D'Alessandro, R.; Da Rold, M.; De Palma, M.; Dell'Orso, R.; Marina, R. Della; Dutta, S.; Eklund, C.; Elliott-Peisert, A.; Favro, G.; Feld, L.; Fiore, L.; Focardi, E.; French, M.; Freudenreich, K.; Fuertjes, A.; Giassi, A.; Giorgi, M.; Giraldo, A.; Glessing, B.; Gu, W.H.; Hall, G.; Hammerstrom, R.; Hebbeker, T.; Hrubec, J.; Huhtinen, M.; Kaminsky, A.; Karimaki, V.; Koenig, St.; Krammer, M.; Lariccia, P.; Lenzi, M.; Loreti, M.; Luebelsmeyer, K.; Lustermann, W.; Maettig, P.; Maggi, G.; Mannelli, M.; Mantovani, G.; Marchioro, A.; Mariotti, C.; Martignon, G.; Evoy, B. Mc; Meschini, M.; Messineo, A.; Migliore, E.; My, S.; Paccagnella, A.; Palla, F.; Pandoulas, D.; Papi, A.; Parrini, G.; Passeri, D.; Pieri, M.; Piperov, S.; Potenza, R.; Radicci, V.; Raffaelli, F.; Raymond, M.; Santocchia, A.; Schmitt, B.; Selvaggi, G.; Servoli, L.; Sguazzoni, G.; Siedling, R.; Silvestris, L.; Skog, K.; Starodumov, A.; Stavitski, I.; Stefanini, G.; Tempesta, P.; Tonelli, G.; Tricomi, A.; Tuuva, T.; Vannini, C.; Verdini, P.G.; Viertel, G.; Xie, Z.; Li Yahong; Watts, S.; Wittmer, B.

2000-01-01

Interstrip and backplane capacitances on silicon microstrip detectors with p + strip on n substrate of 320 μm thickness were measured for pitches between 60 and 240 μm and width over pitch ratios between 0.13 and 0.5. Parametrisations of capacitance w.r.t. pitch and width were compared with data. The detectors were measured before and after being irradiated to a fluence of 4x10 14 protons/cm 2 of 24 GeV/c momentum. The effect of the crystal orientation of the silicon has been found to have a relevant influence on the surface radiation damage, favouring the choice of a substrate. Working at high bias (up to 500 V in CMS) might be critical for the stability of detector, for a small width over pitch ratio. The influence found to enhance the stability

A standard fission neutron irradiation facility

International Nuclear Information System (INIS)

Sahasrabudhe, S.G.; Chakraborty, P.P.; Iyer, M.R.; Kirthi, K.N.; Soman, S.D.

1979-01-01

A fission neutron irradiation facility (FISNIF) has been set up at the thermal column of the CIRUS reactor at BARC. The spectrum and the flux have been measured using threshold detectors. The paper describes the setting up of the facility, measurement and application. A concentric cylinder containing UO 2 powder sealed inside surrounds the irradiation point of a pneumatic sample transfer system located in the thermal column of the reactor. Samples are loaded in a standard aluminium capsule with cadmium lining and transported pneumatically. A sample transfer time of 1 s can be achieved in the facility. Typical applications of the facility for studying activation of iron and sodium in fission neutrons are also discussed. (Auth.)

Applications of CR-39 solid state nuclear track detector to ion beam diagnosis

International Nuclear Information System (INIS)

Kanasaki, Masato; Hattori, Atsuto; Oda, Keiji; Yamauchi, Tomoya; Fukuda, Yuji; Sakaki, Hironao; Nishiuchi, Mamiko; Kondo, Kiminori; Kurashima, Satoshi; Kamiya, Tomihiro

2012-01-01

CR-39 solid state nuclear track detector, which was developed for optical lens, has been applied for various field such as radon surveys, measurement of galactic cosmic ray, cell irradiation experiment and so on. The CR-39 detectors have the great advantages of being insensitive to high energy photons and electrons and capable of detecting only ions in the mixed fields such as laser driven relativistic plasmas. Though there are some analytical methods of CR-39 to diagnose ion beam, unfortunately, only few researchers in the field of plasma know the methods. This article looks at how to use CR-39 detectors and introduce the accomplishment of the joint study JAEA and Kobe Univ. for application of CR-39 detectors to ion beam diagnosis. (author)

Development status of irradiation devices and instrumentation for material and nuclear fuel irradiation tests in HANARO

Energy Technology Data Exchange (ETDEWEB)

Kim, Bong Goo; Sohn, Jae Min; Choo, Kee Nam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-04-15

The High flux Advanced Neutron Application ReactOr (HANARO), an open-tank-in-pool type reactor, is one of the multi-purpose research reactors in the world. Since the commencement of HANARO's operations in 1995, a significant number of experimental facilities have been developed and installed at HANARO, and continued efforts to develop more facilities are in progress. Owing to the stable operation of the reactor and its frequent utilization, more experimental facilities are being continuously added to satisfy various fields of study and diverse applications. The irradiation testing equipment for nuclear fuels and materials at HANARO can be classified into capsules and the Fuel Test Loop (FTL). Capsules for irradiation tests of nuclear fuels in HANARO have been developed for use under the dry conditions of the coolant and materials at HANARO and are now successfully utilized to perform irradiation tests. The FTL can be used to conduct irradiation testing of a nuclear fuel under the operating conditions of commercial nuclear power plants. During irradiation tests conducted using these capsules in HANARO, instruments such as the thermocouple, Linear Variable Differential Transformer (LVDT), small heater, Fluence Monitor (F/M) and Self-Powered Neutron Detector (SPND) are used to measure various characteristics of the nuclear fuel and irradiated material. This paper describes not only the status of HANARO and the status and perspective of irradiation devices and instrumentation for carrying out nuclear fuel and material tests in HANARO but also some results from instrumentation during irradiation tests

Study of the effects of neutron irradiation on silicon strip detectors

Energy Technology Data Exchange (ETDEWEB)

Giubellino, P.; Panizza, G. (INFN Torino (Italy)); Hall, G.; Sotthibandhu, S. (Imperial Coll., London (United Kingdom)); Ziock, H.J.; Ferguson, P.; Sommer, W.F. (Los Alamos National Lab., NM (United States)); Edwards, M. (Rutherford Appleton Lab., Chilton (United Kingdom)); Cartiglia, N.; Hubbard, B.; Leslie, J.; Pitzl, D.; O' Shaughnessy, K.; Rowe, W.; Sadrozinski, H.F.W.; Seiden, A.; Spencer, E. (Santa Cruz Inst. for Particle Physics, Univ. California, CA (United States))

1992-05-01

Silicon strip detectors and test structures were exposed to neutron fluences up to {Phi}=6.1x10{sup 14} n/cm{sup 2}, using the ISIS neutron source at the Rutherford Appleton Laboratory (UK). In this paper we report some of our results concerning the effects of displacement damage, with a comparison of devices made of silicon of different resistivity. The various samples exposed showed a very similar dependence of the leakage current on the fluence received. We studied the change of effective doping concentration, and observed a behaviour suggesting the onset of type inversion at a fluence of {proportional to}2.0x10{sup 13} n/cm{sup 2}, a value which depends on the initial doping concentration. The linear increase of the depletion voltage for fluences higher than the inversion point could eventually determine the maximum fluence tolerable by silicon detectors. (orig.).

Beam tests of ATLAS SCT silicon strip detector modules

CERN Document Server

Campabadal, F; Key, M; Lozano, M; Martínez, C; Pellegrini, G; Rafí, J M; Ullán, M; Johansen, L; Pommeresche, B; Stugu, B; Ciocio, A; Fadeev, V; Gilchriese, M G D; Haber, C; Siegrist, J; Spieler, H; Vu, C; Bell, P J; Charlton, D G; Dowell, John D; Gallop, B J; Homer, R J; Jovanovic, P; Mahout, G; McMahon, T J; Wilson, J A; Barr, A J; Carter, J R; Fromant, B P; Goodrick, M J; Hill, J C; Lester, C G; Palmer, M J; Parker, M A; Robinson, D; Sabetfakhri, A; Shaw, R J; Anghinolfi, F; Chesi, Enrico Guido; Chouridou, S; Fortin, R; Grosse-Knetter, J; Gruwé, M; Ferrari, P; Jarron, P; Kaplon, J; MacPherson, A; Niinikoski, T O; Pernegger, H; Roe, S; Rudge, A; Ruggiero, G; Wallny, R; Weilhammer, P; Bialas, W; Dabrowski, W; Grybos, P; Koperny, S; Blocki, J; Brückman, P; Gadomski, S; Godlewski, J; Górnicki, E; Malecki, P; Moszczynski, A; Stanecka, E; Stodulski, M; Szczygiel, R; Turala, M; Wolter, M; Ahmad, A; Benes, J; Carpentieri, C; Feld, L; Ketterer, C; Ludwig, J; Meinhardt, J; Runge, K; Mikulec, B; Mangin-Brinet, M; D'Onofrio, M; Donega, M; Moêd, S; Sfyrla, A; Ferrère, D; Clark, A G; Perrin, E; Weber, M; Bates, R L; Cheplakov, A P; Saxon, D H; O'Shea, V; Smith, K M; Iwata, Y; Ohsugi, T; Kohriki, T; Kondo, T; Terada, S; Ujiie, N; Ikegami, Y; Unno, Y; Takashima, R; Brodbeck, T; Chilingarov, A G; Hughes, G; Ratoff, P; Sloan, T; Allport, P P; Casse, G L; Greenall, A; Jackson, J N; Jones, T J; King, B T; Maxfield, S J; Smith, N A; Sutcliffe, P; Vossebeld, Joost Herman; Beck, G A; Carter, A A; Lloyd, S L; Martin, A J; Morris, J; Morin, J; Nagai, K; Pritchard, T W; Anderson, B E; Butterworth, J M; Fraser, T J; Jones, T W; Lane, J B; Postranecky, M; Warren, M R M; Cindro, V; Kramberger, G; Mandic, I; Mikuz, M; Duerdoth, I P; Freestone, J; Foster, J M; Ibbotson, M; Loebinger, F K; Pater, J; Snow, S W; Thompson, R J; Atkinson, T M; Bright, G; Kazi, S; Lindsay, S; Moorhead, G F; Taylor, G N; Bachindgagyan, G; Baranova, N; Karmanov, D; Merkine, M; Andricek, L; Bethke, Siegfried; Kudlaty, J; Lutz, Gerhard; Moser, H G; Nisius, R; Richter, R; Schieck, J; Cornelissen, T; Gorfine, G W; Hartjes, F G; Hessey, N P; de Jong, P; Muijs, A J M; Peeters, S J M; Tomeda, Y; Tanaka, R; Nakano, I; Dorholt, O; Danielsen, K M; Huse, T; Sandaker, H; Stapnes, S; Bargassa, Pedrame; Reichold, A; Huffman, T; Nickerson, R B; Weidberg, A; Doucas, G; Hawes, B; Lau, W; Howell, D; Kundu, N; Wastie, R; Böhm, J; Mikestikova, M; Stastny, J; Broklová, Z; Broz, J; Dolezal, Z; Kodys, P; Kubík, P; Reznicek, P; Vorobel, V; Wilhelm, I; Chren, D; Horazdovsky, T; Linhart, V; Pospísil, S; Sinor, M; Solar, M; Sopko, B; Stekl, I; Ardashev, E N; Golovnya, S N; Gorokhov, S A; Kholodenko, A G; Rudenko, R E; Ryadovikov, V N; Vorobev, A P; Adkin, P J; Apsimon, R J; Batchelor, L E; Bizzell, J P; Booker, P; Davis, V R; Easton, J M; Fowler, C; Gibson, M D; Haywood, S J; MacWaters, C; Matheson, J P; Matson, R M; McMahon, S J; Morris, F S; Morrissey, M; Murray, W J; Phillips, P W; Tyndel, M; Villani, E G; Dorfan, D E; Grillo, A A; Rosenbaum, F; Sadrozinski, H F W; Seiden, A; Spencer, E; Wilder, M; Booth, P; Buttar, C M; Dawson, I; Dervan, P; Grigson, C; Harper, R; Moraes, A; Peak, L S; Varvell, K E; Chu Ming Lee; Hou Li Shing; Lee Shih Chang; Teng Ping Kun; Wan Chang Chun; Hara, K; Kato, Y; Kuwano, T; Minagawa, M; Sengoku, H; Bingefors, N; Brenner, R; Ekelöf, T J C; Eklund, L; Bernabeu, J; Civera, J V; Costa, M J; Fuster, J; García, C; García, J E; González-Sevilla, S; Lacasta, C; Llosa, G; Martí i García, S; Modesto, P; Sánchez, J; Sospedra, L; Vos, M; Fasching, D; González, S; Jared, R C; Charles, E

2005-01-01

The design and technology of the silicon strip detector modules for the Semiconductor Tracker (SCT) of the ATLAS experiment have been finalised in the last several years. Integral to this process has been the measurement and verification of the tracking performance of the different module types in test beams at the CERN SPS and the KEK PS. Tests have been performed to explore the module performance under various operating conditions including detector bias voltage, magnetic field, incidence angle, and state of irradiation up to 3 multiplied by 1014 protons per square centimetre. A particular emphasis has been the understanding of the operational consequences of the binary readout scheme.

3600 digital phase detector with 100-kHz bandwidth

International Nuclear Information System (INIS)

Reid, D.W.; Riggin, D.; Fazio, M.V.; Biddle, R.S.; Patton, R.D.; Jackson, H.A.

1981-01-01

The general availability of digital circuit components with propagation delay times of a few nanoseconds makes a digital phase detector with good bandwidth feasible. Such a circuit has a distinct advantage over its analog counterpart because of its linearity over wide range of phase shift. A phase detector that is being built at Los Alamos National Laboratory for the Fusion Materials Irradiation Test (FMIT) project is described. The specifications are 100-kHz bandwidth, linearity of +- 1 0 over +- 180 0 of phase shift, and 0.66 0 resolution. To date, the circuit has achieved the bandwidth and resolution. The linearity is approximately +- 3 0 over +- 180 0 phase shift

Focusing mirrors for enhanced neutron radiography with thermal neutrons and application for irradiated nuclear fuel

Science.gov (United States)

Rai, Durgesh K.; Abir, Muhammad; Wu, Huarui; Khaykovich, Boris; Moncton, David E.

2018-01-01

Neutron radiography is a powerful method of probing the structure of materials based on attenuation of neutrons. This method is most suitable for materials containing heavy metals, which are not transparent to X-rays, for example irradiated nuclear fuel and other nuclear materials. Neutron radiography is one of the first non-distractive post-irradiated examination methods, which is applied to gain an overview of the integrity of irradiated nuclear fuel and other nuclear materials. However, very powerful gamma radiation emitted by the samples is damaging to the electronics of digital imaging detectors and has so far precluded the use of modern detectors. Here we describe a design of a neutron microscope based on focusing mirrors suitable for thermal neutrons. As in optical microscopes, the sample is separated from the detector, decreasing the effect of gamma radiation. In addition, the application of mirrors would result in a thirty-fold gain in flux and a resolution of better than 40 μm for a field-of-view of about 2.5 cm. Such a thermal neutron microscope can be useful for other applications of neutron radiography, where thermal neutrons are advantageous.

Design and fabrication of a self-powered neutron detector

International Nuclear Information System (INIS)

Garcia Garcia, Florencio.

1979-01-01

Self powered neutron detectors are becoming more and more popular in reactor instrumentation. A fast response detector of this type was made at the Reactor Division, La Reina Nuclear Center in Santiago. Cobalt wire was the emitter, teflon the insulator and a stainless steel tubing was the collector. The overall dimensions of the detector are 6 mms diameter and 700 mms length. The irradiation tests, carried out at the Center's 5 Mw research reactor showed a very reasonably linear relation between current supplied by the detector and thermal neutron flux, over a range extending from 10 10 to 10 13 n/cm 2 x seg. These tests also showed a good agreement between calculated and measured current. The models used for the calculation of current are fully explained and they include some improvements over those that have been published recently. An important conclusion for the case of the cobalt detectors is that the wire's diameter must be at least 1 mm. in order to have a neutron induced current bigger than the parasitic components generated by indirect processes. Calculations for other emitters such as vanadium, silver and rhodum are also included. (EC)

Characterization of irradiated APDs for picosecond time measurements

Science.gov (United States)

Centis Vignali, M.; Dalal, R.; Gallinaro, M.; Harrop, B.; Jain, G.; Lu, C.; McClish, M.; McDonald, K. T.; Moll, M.; Newcomer, F. M.; Ugobono, S. Otero; White, S.

2018-01-01

For their operation at the CERN High Luminosity Large Hadron Collider (HL-LHC), the ATLAS and CMS experiments are planning to implement dedicated systems to measure the time of arrival of minimum ionizing particles with an accuracy of about 30 ps. The timing detectors will be subjected to radiation levels corresponding up to a 1-MeV neutrons fluence (Φeq) of 1015 cm-2 for the goal integrated luminosity of HL-LHC of 3000 fb-1. In this paper, deep-diffused Avalanche Photo Diodes (APDs) produced by Radiation Monitoring Devices are examined as candidate timing detectors for HL-LHC applications. These APDs are operated at 1.8 kV, resulting in a gain of up to 500. The timing performance of the detectors is evaluated using a pulsed laser. The effects of radiation damage on current, signal amplitude, noise, and timing performance of the APDs are evaluated using detectors irradiated with neutrons up to Φeq = 1015 cm-2.

Interdefect charge exchange in silicon particle detectors at cryogenic temperatures

CERN Document Server

MacEvoy, B; Hall, G; Moscatelli, F; Passeri, D; Santocchia, A

2002-01-01

Silicon particle detectors in the next generation of experiments at the CERN Large Hadron Collider will be exposed to a very challenging radiation environment. The principal obstacle to long-term operation arises from changes in detector doping concentration (N/sub eff/), which lead to an increase in the bias required to deplete the detector and hence achieve efficient charge collection. We have previously presented a model of interdefect charge exchange between closely spaced centers in the dense terminal clusters formed by hadron irradiation. This manifestly non-Shockley-Read-Hall (SRH) mechanism leads to a marked increase in carrier generation rate and negative space charge over the SRH prediction. There is currently much interest in the subject of cryogenic detector operation as a means of improving radiation hardness. Our motivation, however, is primarily to investigate our model further by testing its predictions over a range of temperatures. We present measurements of spectra from /sup 241/Am alpha par...

Pixel pitch and particle energy influence on the dark current distribution of neutron irradiated CMOS image sensors.

Science.gov (United States)

Belloir, Jean-Marc; Goiffon, Vincent; Virmontois, Cédric; Raine, Mélanie; Paillet, Philippe; Duhamel, Olivier; Gaillardin, Marc; Molina, Romain; Magnan, Pierre; Gilard, Olivier

2016-02-22

The dark current produced by neutron irradiation in CMOS Image Sensors (CIS) is investigated. Several CIS with different photodiode types and pixel pitches are irradiated with various neutron energies and fluences to study the influence of each of these optical detector and irradiation parameters on the dark current distribution. An empirical model is tested on the experimental data and validated on all the irradiated optical imagers. This model is able to describe all the presented dark current distributions with no parameter variation for neutron energies of 14 MeV or higher, regardless of the optical detector and irradiation characteristics. For energies below 1 MeV, it is shown that a single parameter has to be adjusted because of the lower mean damage energy per nuclear interaction. This model and these conclusions can be transposed to any silicon based solid-state optical imagers such as CIS or Charged Coupled Devices (CCD). This work can also be used when designing an optical imager instrument, to anticipate the dark current increase or to choose a mitigation technique.

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

Modeling the impact of preflushing on CTE in proton irradiated CCD-based detectors

Science.gov (United States)

Philbrick, R. H.

2002-04-01

A software model is described that performs a "real world" simulation of the operation of several types of charge-coupled device (CCD)-based detectors in order to accurately predict the impact that high-energy proton radiation has on image distortion and modulation transfer function (MTF). The model was written primarily to predict the effectiveness of vertical preflushing on the custom full frame CCD-based detectors intended for use on the proposed Kepler Discovery mission, but it is capable of simulating many other types of CCD detectors and operating modes as well. The model keeps track of the occupancy of all phosphorous-silicon (P-V), divacancy (V-V) and oxygen-silicon (O-V) defect centers under every CCD electrode over the entire detector area. The integrated image is read out by simulating every electrode-to-electrode charge transfer in both the vertical and horizontal CCD registers. A signal level dependency on the capture and emission of signal is included and the current state of each electrode (e.g., barrier or storage) is considered when distributing integrated and emitted signal. Options for performing preflushing, preflashing, and including mini-channels are available on both the vertical and horizontal CCD registers. In addition, dark signal generation and image transfer smear can be selectively enabled or disabled. A comparison of the charge transfer efficiency (CTE) data measured on the Hubble space telescope imaging spectrometer (STIS) CCD with the CTE extracted from model simulations of the STIS CCD show good agreement.

Two specialized delayed-neutron detector designs for assays of fissionable elements in water and sediment samples

International Nuclear Information System (INIS)

Balestrini, S.J.; Balagna, J.P.; Menlove, H.O.

1976-01-01

Two specialized neutron-sensitive detectors are described which are employed for rapid assays of fissionable elements by sensing for delayed neutrons emitted by samples after they have been irradiated in a nuclear reactor. The more sensitive of the two detectors, designed to assay for uranium in water samples, is 40% efficient; the other, designed for sediment sample assays, is 27% efficient. These detectors are also designed to operate under water as an inexpensive shielding against neutron leakage from the reactor and neutrons from cosmic rays. (Auth.)

Recent Advances in Diamond Detectors

CERN Document Server

Trischuk, W.

2008-01-01

With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2012, ATLAS and CMS are planning for detector upgrades for their innermost layers requiring radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is now planned for all LHC experiments. This material is now being considered as an alternate sensor for use very close to the interaction region of the super LHC where the most extreme radiation conditions will exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences available. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8 x 10^16 protons/cm^2 showing that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve allowing one t...

Filter-fluorescer x-ray spectrometer using solid state detectors for γ-ray background reduction

International Nuclear Information System (INIS)

Yokoi, Takashi; Kitagawa, Yoneyoshi; Shiraga, Hiroyuki; Matsunaga, Hirohide; Kato, Yoshiaki; Yamanaka, Chiyoe.

1986-01-01

Filter-fluorescer x-ray spectrometer using solid state photo-detectors instead of the photomultiplier tubes in order to reduce the γ-ray background noise is reported. A significant reduction of the γ-ray background noise is expected, because solid state photo-detectors are very small in size compared with the photomultiplier tubes. It has been confirmed that the γ-ray background is reduced in the target irradiation experiments with the Gekko MII glass laser. (author)

Defect characterization in high-purity silicon after γ- and hadron irradiation

International Nuclear Information System (INIS)

Stahl, J.

2004-07-01

The challenge for silicon particle detectors in future high energy physics experiments caused by extreme radiation fields can only be met by an appropriate defect engineering of the starting material. Appreciable improvements had already been obtained by enriching high resistivity float zone silicon with oxygen as demonstrated by the CERN RD48 collaboration. This thesis will focus on the difference observed after irradiation between standard and oxygenated float zone and detector grade Czochralski silicon. Results obtained with diodes manufactured on epitaxial layers are also included, envisioning effects arising from the possible migration of impurities during the crystal growth from the oxygen rich Czochralski substrate. Deep level transient spectroscopy (DLTS) and thermally stimulated current (TSC) measurements have been performed for defect characterization after γ- and hadron irradiation. Also a new high resolution DLTS technique has been used for the first time to separate defect levels with similar parameters. During the microscopic studies additionally to the well known defects like VO i , V 2 , C i O i or VP, four new radiation induced defects have been discovered and characterized. Two of these defects are closely correlated with the detector performance: A deep acceptor labeled as I-defect, and a bistable donor (BD). The formation of the I-defect is strongly suppressed in oxygen rich materials, while the formation of the BD is suppressed in oxygen lean material. With their properties the I- and the BD-defect are able to explain the different macroscopic behavior of standard and oxygen enriched float zone silicon after γ-irradiation. Furthermore, the BD defect is most probably responsible for the observation that in Cz and Epi diodes space charge sign inversion does not occur even after high fluences of proton irradiation. Additionally the γ-irradiated diodes were annealed at temperatures between 100 C and 350 C. During these studies some new reaction

High-rate performance of muon drift tube detectors

International Nuclear Information System (INIS)

Schwegler, Philipp

2014-01-01

The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are studied. The resolution and efficiency of sMDT chambers at high γ-ray and proton irradiation rates well beyond the ones expected at HL-LHC have been measured and the irradiation effects understood using detailed simulations. The sMDT chambers offer an about an order of magnitude better rate capability and are an ideal replacement for the MDT chambers because of compatibility of services and read-out. The limitations of the sMDT chambers are now in the read-out electronics, taken from the MDT chambers, to which improvements for even higher rate capability are proposed.

Results obtained with the passive radiation detectors in the ICCHIBAN-4 experiment

International Nuclear Information System (INIS)

Bilski, P.; Horwacik, T.

2005-05-01

In frame of the InterComparison of Cosmic rays with Heavy Ions Beams at NIRS (ICCHIBAN) organized at the HIMAC accelerator in Chiba several types of the thermoluminescent detectors (TLD), as well as CR-39 track detectors, were exposed. Four different types of TLDs were used: MTS-7 ( 7 LiF:Mg,Ti), MTS-6 ( 6 LiF:Mg,Ti), MCP-7 ( 7 LiF:Mg,Cu,P) and MTT-7 ( 7 LiF:Mg,Ti with changed activator composition. All TLDs were manufactured at the Institute of Nuclear Physics (INP) in Cracow. The detectors were irradiated with various doses of He, C, Ne and Fe ions. Part of exposures were done in unknown conditions, to test measuring capabilities of the detectors. For analyses of these results, the method of obtaining information on ionisation density of an unknown radiation field, which is based on ratios of responses of different LiF detectors, was successfully used. (author)

Aging Analysis of Micromegas Detectors for ATLAS New Small Wheel

CERN Document Server

Quinnan, Melissa

2015-01-01

In preparation for the coming High Luminosity Large Hadron Collider (HL-LHC) upgrade, the New Small Wheel (NSW) will replace the Small Wheel of the ATLAS Muon Spectrometer as part of the 2018 ATLAS Phase-I upgrade. Micromegas (MM) detectors will serve as one component of the NSW. These gaseous micro-mesh detectors will accommodate the higher luminosity and trigger rate of the future HL-LHC.In order to predict performance of MM after several years in the HL-LHC, radiation aging tests were conducted in the Gamma Irradiation Facility (GIF++) using a Cs 137 source. Two small MM prototype "T" chambers were irradiated and studied over the course of several months to accelerate the aging process and characterize chamber behavior. This report outlines a record of the aging process thus far and demonstrates techniques used to describe aging effects, namely measurements of average current, integrated charge, and gain. These will be used in the ongoing aging analysis of the T chambers and in future aging studies of the ...

Photoluminescence detection of alpha particle using DAM-ADC nuclear detector

Energy Technology Data Exchange (ETDEWEB)

Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); Harraz, Farid A., E-mail: fharraz68@yahoo.com [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box: 87 Helwan, Cairo 11421 (Egypt); Ali, Atif M. [Department of Physics, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Al-Sayari, S.A. [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); College of Science and Arts-Sharoura, Najran University (Saudi Arabia); Al-Hajry, A. [Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia)

2016-09-11

The photoluminescence (PL) and UV–vis spectral analysis of DAM-ADC (diallyl maleate: DAM, polyallyl diglycol carbonate: ADC) nuclear detector are demonstrated for the first time. The DAM-ADC surfaces were exposed to thin {sup 241}Am disk source that emits alpha particles with activity 333 kBq. It is found that the track density of the irradiated samples remarkably influences the PL characteristics of the DAM-ADC detector. The spectral peak heights and the integrated intensities under the peaks exhibit linear correlations with correlation coefficient R{sup 2}=0.9636 and 0.9806, respectively for different alpha particle fluences ranging from 8.16–40.82×10{sup 7} particles/cm{sup 2}. Additionally, a correlation coefficient R{sup 2}=0.9734 was achieved for the UV–vis spectral analysis. The linear fitting functions, along with the corresponding fitting parameters were evaluated in each case. Both the PL and the UV–vis data of the irradiated DAM-ADC samples showed considerable spectral differences, and hence they would be used to offer sensitive approaches for alpha particle detection.

Sensor development for the CMS pixel detector

CERN Document Server

Bölla, G; Horisberger, R P; Kaufmann, R; Rohe, T; Roy, A

2002-01-01

The CMS experiment which is currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) will contain a pixel detector which provides in its final configuration three space points per track close to the interaction point of the colliding beams. Because of the harsh radiation environment of the LHC, the technical realization of the pixel detector is extremely challenging. The readout chip as the most damageable part of the system is believed to survive a particle fluence of 6x10 sup 1 sup 4 n sub e sub q /cm sup 2 (All fluences are normalized to 1 MeV neutrons and therefore all components of the hybrid pixel detector have to perform well up to at least this fluence. As this requires a partially depleted operation of the silicon sensors after irradiation-induced type inversion of the substrate, an ''n in n'' concept has been chosen. In order to perform IV-tests on wafer level and to hold accidentally unconnected pixels close to ground potential, a resistive path between the pixe...

Single crystal diamond detectors grown by chemical vapor deposition

International Nuclear Information System (INIS)

Tuve, C.; Angelone, M.; Bellini, V.; Balducci, A.; Donato, M.G.; Faggio, G.; Marinelli, M.; Messina, G.; Milani, E.; Morgada, M.E.; Pillon, M.; Potenza, R.; Pucella, G.; Russo, G.; Santangelo, S.; Scoccia, M.; Sutera, C.; Tucciarone, A.; Verona-Rinati, G.

2007-01-01

The detection properties of heteropitaxial (polycrystalline, pCVD) and homoepitaxial (single crystal, scCVD) diamond films grown by microwave chemical vapor deposition (CVD) in the Laboratories of Roma 'Tor Vergata' University are reported. The pCVD diamond detectors were tested with α-particles from different sources and 12 C ions produced by 15MV Tandem accelerator at Southern National Laboratories (LNS) in Catania (Italy). pCVDs were also used to monitor 14MeV neutrons produced by the D-T plasma at Joint European Torus (JET), Culham, U.K. The limit of pCVDs is the poor energy resolution. To overcome this problem, we developed scCVD diamonds using the same reactor parameters that optimized pCVD diamonds. scCVD were grown on a low cost (100) HPHT single crystal substrate. A detector 110μm thick was tested under α-particles and under 14MeV neutron irradiation. The charge collection efficiency spectrum measured under irradiation with a triple α-particle source shows three clearly resolved peaks, with an energy resolution of about 1.1%. The measured spectra under neutron irradiation show a well separated C(n,α 0 ) 9 Be12 reaction peak with an energy spread of 0.5MeV for 14.8MeV neutrons and 0.3MeV for 14.1MeV neutrons, which are fully compatible with the energy spread of the incident neutron beams

The effect of solarradiation and UV photons on the CR-39 nuclear track detector

International Nuclear Information System (INIS)

Saad, A.F.

2003-01-01

The effects induced in the CR-39 polymer detector by total solar radiation (TSR) and UV photons were investigated. Thr exposure of detector samples to solar photons was carried out according to certain conditions. The TSR exposure period started in the middle of july and lasted unitel 12 th of september. 2000: the hottest months in zagazig, egypt. Another set of detector samples was exposed to UV photons from a UV lamp for different intervals. After UV exposure, these detectors were analysed with an FT-IR sepectrometer of jasco type 5300 in transmission mode. The FT-IR spectra does not show any considerable modifications due to UV irradiation in that detector. The effects of UV light were compared with those of solar radiation containing ultraviolet photons , on the registration properties of this polymer detector. Preliminaryresults revealed a proportionate increase in bluk etch rate of CR-39 detector with the increase of exposure time to the solar radiation. The results indicated that the CR-39 polymer detector can be used as a solar radiation dosimeter

Burn-Up Determination by High Resolution Gamma Spectrometry: Spectra from Slightly-Irradiated Uranium and Plutonium between 400-830 keV

International Nuclear Information System (INIS)

Forsyth, R.S.; Ronqvist, N.

1966-08-01

Previously published studies of the short-cooled fission product spectra of irradiated uranium have been severely restricted by the poor energy resolution of the sodium iodide detectors used. In this report are presented fission product spectra of irradiated uranium and plutonium obtained by means of a lithium-drifted germanium detector. The resolved gamma peaks have been assigned to various fission products by correlation of measured energy and half-life values with published data. By simultaneous study of the spectra of two irradiated mixtures of plutonium and uranium, the possibility of using the activities of Ru-103 and Ru-106 as a measure of the relative fission rate in U-235 and Pu-239 has been briefly examined

Burn-Up Determination by High Resolution Gamma Spectrometry: Spectra from Slightly-Irradiated Uranium and Plutonium between 400-830 keV

Energy Technology Data Exchange (ETDEWEB)

Forsyth, R S; Ronqvist, N

1966-08-15

Previously published studies of the short-cooled fission product spectra of irradiated uranium have been severely restricted by the poor energy resolution of the sodium iodide detectors used. In this report are presented fission product spectra of irradiated uranium and plutonium obtained by means of a lithium-drifted germanium detector. The resolved gamma peaks have been assigned to various fission products by correlation of measured energy and half-life values with published data. By simultaneous study of the spectra of two irradiated mixtures of plutonium and uranium, the possibility of using the activities of Ru-103 and Ru-106 as a measure of the relative fission rate in U-235 and Pu-239 has been briefly examined.

Polarization of silicon detectors by minimum ionizing particles

CERN Document Server

Dezillie, B; Li, Z; Verbitskaya, E

2000-01-01

This work presents quantitative predictions of the properties of highly irradiated (e.g. by high-energy particles, up to an equivalent fluence of 1x10 sup 1 sup 4 n cm sup - sup 2) silicon detectors operating at cryogenic temperature. It is shown that the exposure to the Minimum Ionising Particle (MIP) with counting rates of about 10 sup 6 cm sup - sup 2 s sup - sup 1 can influence the electric field distribution in the detector's sensitive volume. This change in the electric field distribution and its effect on the charge collection efficiency are discussed in the frame of a model based on trapping of carriers generated by MIPs. The experiment was performed at 87 K with an infrared (1030 nm) laser to simulate MIPs.

The alanine detector in BNCT dosimetry: dose response in thermal and epithermal neutron fields.

Science.gov (United States)

Schmitz, T; Bassler, N; Blaickner, M; Ziegner, M; Hsiao, M C; Liu, Y H; Koivunoro, H; Auterinen, I; Serén, T; Kotiluoto, P; Palmans, H; Sharpe, P; Langguth, P; Hampel, G

2015-01-01

The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a (60)Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes fluka and mcnp. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen & Olsen alanine response model. The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. The alanine detector can be used without