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.).

Shock-resistant gamma-ray detector tube

International Nuclear Information System (INIS)

1979-01-01

A simple durable scintillation detector is described which, it is claimed, offers a solution to the shock resistance problems encountered when gamma detectors are used for deep bore hole well logging or in space vehicles. The shock resistant detector consists of an elongate sodium iodide scintillation crystal and rigid metal container with a round glass optical window at one end of the container and a metal end closure cap at the opposite end. An elastic rubber compression pad is provided between the end cap and the scintillation crystal to bias the crystal axially toward the glass window. An extension transparent silicone rubber light pipe of substantial axial thickness permanently couples the optical window to the crystal while allowing substantial movement under high g forces. (U.K.)

Nanosecond X-ray detector based on high resistivity ZnO single crystal semiconductor

Energy Technology Data Exchange (ETDEWEB)

Zhao, Xiaolong; He, Yongning, E-mail: yongning@mail.xjtu.edu.cn; Peng, Wenbo; Huang, Zhiyong; Qi, Xiaomeng; Pan, Zijian; Zhang, Wenting [School of Electronic and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Liang; Liu, Jinliang; Zhang, Zhongbing; Ouyang, Xiaoping [Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

2016-04-25

The pulse radiation detectors are sorely needed in the fields of nuclear reaction monitoring, material analysis, astronomy study, spacecraft navigation, and space communication. In this work, we demonstrate a nanosecond X-ray detector based on ZnO single crystal semiconductor, which emerges as a promising compound-semiconductor radiation detection material for its high radiation tolerance and advanced large-size bulk crystal growth technique. The resistivity of the ZnO single crystal is as high as 10{sup 13} Ω cm due to the compensation of the donor defects (V{sub O}) and acceptor defects (V{sub Zn} and O{sub i}) after high temperature annealing in oxygen. The photoconductive X-ray detector was fabricated using the high resistivity ZnO single crystal. The rise time and fall time of the detector to a 10 ps pulse electron beam are 0.8 ns and 3.3 ns, respectively, indicating great potential for ultrafast X-ray detection applications.

Investigation of the oxygen-vacancy (A-center) defect complex profile in neutron irradiated high resistivity silicon junction particle detectors

International Nuclear Information System (INIS)

Li, Zheng; Kraner, H.W.; Verbitskaya, E.; Eremin, V.; Ivanov, A.; Rubinelli, F.A.; Fonash, S.J.

1992-02-01

Distributions of the A-center (oxygen-vacancy) in neutron silicon detectors have been studied using Deep Level Transient Spectroscopy. A-centers have been found to be nearly uniformly distributed in the silicon water depth for medium resistivity (0.1 - 0.2 kΩ-cm) silicon detectors. A positive filling pulse was needed to detect the A-centers in high resistivity (>4 kΩ-cm) silicon detectors, and this effect was found to be dependent on the oxidation temperature. A discussion of this effect is presented. 16 refs

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)

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

Reliability studies of high operating temperature MCT photoconductor detectors

Science.gov (United States)

Wang, Wei; Xu, Jintong; Zhang, Yan; Li, Xiangyang

2010-10-01

This paper concerns HgCdTe (MCT) infrared photoconductor detectors with high operating temperature. The near room temperature operation of detectors have advantages of light weight, less cost and convenient usage. Their performances are modest and they suffer from reliable problems. These detectors face with stability of the package, chip bonding area and passivation layers. It's important to evaluate and improve the reliability of such detectors. Defective detectors were studied with SEM(Scanning electron microscope) and microscopy. Statistically significant differences were observed between the influence of operating temperature and the influence of humidity. It was also found that humility has statistically significant influence upon the stability of the chip bonding and passivation layers, and the amount of humility isn't strongly correlated to the damage on the surface. Considering about the commonly found failures modes in detectors, special test structures were designed to improve the reliability of detectors. An accelerated life test was also implemented to estimate the lifetime of the high operating temperature MCT photoconductor 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...

Remote calibration of Resistance Temperature Devices (RTDs): Final report

International Nuclear Information System (INIS)

Blalock, T.V.; Roberts, M.J.

1988-02-01

Johnson noise power measuring techniques have been used to calibrate platinum resistance temperature detectors (RTDs) installed in an operating nuclear plant - Connecticut Yankee Atomic Power Company's Haddam Neck Nuclear Plant - achieving agreement with the dc calibration from better than 0.1% to as much as 1% (0.54 to 9.7 0 F) at the normal operating temperature of 585 0 F. Tests were also conducted at plant shutdown conditions. In this application, RTDs with an ice point resistance of 200 Ω were connected with four-wire extension cables approximately 100-ft long to a test station in containment. Methods were developed for in situ characterization of the extension cables and for quantitative measurement of and correction for nonthermal induced noise. Analysis of dc calibration methods showed that resistance-temperature tables used with industrial PRTs may be in error by 0.2 0 F or 0.02% A (expressed as a percentage of absolute temperature in either Kelvin or degrees Rankine) at 540 0 F. Recalibration of the RTDs measured in the plant tests showed differences of about 2.5 0 F or 0.2% A at 540 0 F from calibration tables used in the plant

Pressure balanced type membrane covered polarographic oxygen detectors for use in high temperature-high pressure water, (1)

International Nuclear Information System (INIS)

Nakayama, Norio; Uchida, Shunsuke

1984-01-01

A pressure balanced type membrane covered polarographic oxygen detector was developed to determine directly oxygen concentrations in high temperature, high pressure water without cooling and pressure reducing procedures. The detector is characterized by the following features: (1) The detector body and the membrane for oxygen penetration are made of heat resistant resin. (2) The whole detector body is contained in a pressure chamber where interior and exterior pressures of the detector are balanced. (3) Thermal expansion of the electrolyte is absorbed by deformation of a diaphragm attached to the detector bottom. (4) The effect of dissolved Ag + on the signal current is eliminated by applying a guard electrode. As a result of performance tests at elevated temperature, it was demonstrated that a linear relationship between oxygen concentration and signal current was obtained up to 285 0 C, which was stabilized by the guard electrode. The minimum O 2 concentration detectable was 0.03ppm (9.4 x 10 -7 mol/kg). (author)

Performance of μ-RWELL detector vs resistivity of the resistive stage

Science.gov (United States)

Bencivenni, G.; De Oliveira, R.; Felici, G.; Gatta, M.; Morello, G.; Ochi, A.; Lener, M. Poli; Tskhadadze, E.

2018-04-01

The μ-RWELL is a compact spark-protected single amplification stage Micro-Pattern-Gaseous-Detector (MPGD). The detector amplification stage is realized with a polyimide structure, micro-patterned with a dense matrix of blind-holes, integrated into the readout structure. The anode is formed by a thin Diamond Like Carbon (DLC) resistive layer separated by an insulating glue layer from the readout strips. The introduction of the resistive layer strongly suppressing the transition from streamer to spark gives the possibility to achieve large gains (> 104), without significantly affecting the capability to be efficiently operated in high particle fluxes. In this work we present the results of a systematic study of the μ-RWELL performance as a function of the DLC resistivity. The tests have been performed either with collimated 5.9 keV X-rays or with pion and muon beams at the SPS Secondary Beamline H4 and H8 at CERN.

High Temperature Superconductor Resonator Detectors

Data.gov (United States)

National Aeronautics and Space Administration — High Temperature Superconductor (HTS) infrared detectors were studied for years but never matured sufficiently for infusion into instruments. Several recent...

Bell inequalities resistant to detector inefficiency

International Nuclear Information System (INIS)

Massar, Serge; Pironio, Stefano; Roland, Jeremie; Gisin, Bernard

2002-01-01

We derive both numerically and analytically Bell inequalities and quantum measurements that present enhanced resistance to detector inefficiency. In particular, we describe several Bell inequalities which appear to be optimal with respect to inefficient detectors for small dimensionality d=2,3,4 and two or more measurement settings at each side. We also generalize the family of Bell inequalities described by Collins et al. [Phys. Rev. Lett. 88, 040404 (2002)] to take into account the inefficiency of detectors. In addition, we consider the possibility for pairs of entangled particles to be produced with probability less than 1. We show that when the pair production probability is small, one should in general use different Bell inequalities than when the pair production probability is high

High-Rate Glass Resistive Plate Chambers For LHC Muon Detectors Upgrade

CERN Document Server

Laktineh, I; Cauwenbergh, S; Combret, C; Crotty, I; Haddad, Y; Grenier, G; Guida, R; Kieffer, R; Lumb, N; Mirabito, L; Schirra, F; Seguin, N; Tytgat, M; Van der Donckt, M; Wang, Y; Zaganidis, N

2012-01-01

The limitation of the detection rate of standard bakelite resistive plate chambers (RPC) used as muon detector in LHC experiments is behind the absence of such detectors in the high TJ regions in both CMS and ATLAS detectors. RPCs made with low resistivity glass plates (10ID O.cm) could be an adequate solution to equip the high TJ regions extending thus both the trigger efficiency and the physics performance. Different beam tests with single and multi-gap configurations using the new glass have shown that such detectors can operate at few thousands Hzlcm2 with high efficiency( > 90%).

Photosensitive Gaseous Detectors for Cryogenic Temperature Applications

CERN Document Server

Periale, L; Iacobaeus, C; Lund-Jensen, B; Picchi, P; Pietropaolo, F

2007-01-01

There are several proposals and projects today for building LXe Time Projection Chambers (TPCs) for dark matter search. An important element of these TPCs are the photomultipliers operating either inside LXe or in vapors above the liquid. We have recently demonstrated that photosensitive gaseous detectors (wire type and hole-type) can operate perfectly well until temperatures of LN2. In this paper results of systematic studies of operation of the photosensitive version of these detectors (combined with reflective or semi-transparent CsI photocathodes) in the temperature interval of 300-150 K are presented. In particular, it was demonstrated that both sealed and flushed by a gas detectors could operate at a quite stable fashion in a year/time scale. Obtained results, in particular the long-term stability of photosensitive gaseous detectors, strongly indicate that they can be cheap and simple alternatives to photomultipliers or avalanche solid-state detectors in LXe TPC applications.

Characterization and Calibration of Large Area Resistive Strip Micromegas Detectors

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00389527; The ATLAS collaboration

2016-01-01

Resistive strip Micromegas detectors are discharge tolerant. They have been tested extensively as small detectors of about 10 x 10 cm$^2$ in size and they work reliably at high rates of 100 kHz/cm$^2$ and above. Tracking resolution well below 100 $\\mu$m has been observed for 100 GeV muons and pions. Micromegas detectors are meanwhile proposed as large area muon precision trackers of 2-3 m$^2$ in size. To investigate possible differences between small and large detectors, a 1 m$^2$ detector with 2048 resistive strips at a pitch of 450 $\\mu$m was studied in the LMU Cosmic Ray Measurement Facility (CRMF) using two 4 $\\times$ 2.2 m$^2$ large Monitored Drift Tube (MDT) chambers for cosmic muon reference tracking. A segmentation of the resistive strip anode plane in 57.6 mm x 93 mm large areas has been realized by the readout of 128 strips with one APV25 chip each and by eleven 93 mm broad trigger scintillators placed along the readout strips. This allows for mapping of homogeneity in pulse height and efficiency, d...

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).

Electric fields, weighting fields, signals and charge diffusion in detectors including resistive materials

International Nuclear Information System (INIS)

Riegler, W.

2016-01-01

In this report we discuss static and time dependent electric fields in detector geometries with an arbitrary number of parallel layers of a given permittivity and weak conductivity. We derive the Green's functions i.e. the field of a point charge, as well as the weighting fields for readout pads and readout strips in these geometries. The effect of 'bulk' resistivity on electric fields and signals is investigated. The spreading of charge on thin resistive layers is also discussed in detail, and the conditions for allowing the effect to be described by the diffusion equation is discussed. We apply the results to derive fields and induced signals in Resistive Plate Chambers, MICROMEGAS detectors including resistive layers for charge spreading and discharge protection as well as detectors using resistive charge division readout like the MicroCAT detector. We also discuss in detail how resistive layers affect signal shapes and increase crosstalk between readout electrodes.

Electric fields, weighting fields, signals and charge diffusion in detectors including resistive materials

CERN Document Server

Riegler, Werner

2016-11-07

In this report we discuss static and time dependent electric fields in detector geometries with an arbitrary number of parallel layers of a given permittivity and weak conductivity. We derive the Green's functions i.e. the field of a point charge, as well as the weighting fields for readout pads and readout strips in these geometries. The effect of 'bulk' resistivity on electric fields and signals is investigated. The spreading of charge on thin resistive layers is also discussed in detail, and the conditions for allowing the effect to be described by the diffusion equation is discussed. We apply the results to derive fields and induced signals in Resistive Plate Chambers, Micromega detectors including resistive layers for charge spreading and discharge protection as well as detectors using resistive charge division readout like the MicroCAT detector. We also discuss in detail how resistive layers affect signal shapes and increase crosstalk between readout electrodes.

Automatic control and detector for three-terminal resistance measurement

Science.gov (United States)

Fasching, George E.

1976-10-26

A device is provided for automatic control and detection in a three-terminal resistance measuring instrument. The invention is useful for the rapid measurement of the resistivity of various bulk material with a three-terminal electrode system. The device maintains the current through the sample at a fixed level while measuring the voltage across the sample to detect the sample resistance. The three-electrode system contacts the bulk material and the current through the sample is held constant by means of a control circuit connected to a first of the three electrodes and works in conjunction with a feedback controlled amplifier to null the voltage between the first electrode and a second electrode connected to the controlled amplifier output. An A.C. oscillator provides a source of sinusoidal reference voltage of the frequency at which the measurement is to be executed. Synchronous reference pulses for synchronous detectors in the control circuit and an output detector circuit are provided by a synchronous pulse generator. The output of the controlled amplifier circuit is sampled by an output detector circuit to develop at an output terminal thereof a D.C. voltage which is proportional to the sample resistance R. The sample resistance is that segment of the sample between the area of the first electrode and the third electrode, which is connected to ground potential.

Resistive-strips micromegas detectors with two-dimensional readout

Science.gov (United States)

Byszewski, M.; Wotschack, J.

2012-02-01

Micromegas detectors show very good performance for charged particle tracking in high rate environments as for example at the LHC. It is shown that two coordinates can be extracted from a single gas gap in these detectors. Several micromegas chambers with spark protection by resistive strips and two-dimensional readout have been tested in the context of the R&D work for the ATLAS Muon System upgrade.

Alpha-ray spectrometry at high temperature by using a compound semiconductor detector.

Science.gov (United States)

Ha, Jang Ho; Kim, Han Soo

2013-11-01

The use of conventional radiation detectors in harsh environments is limited by radiation damage to detector materials and by temperature constraints. We fabricated a wide-band gap semiconductor radiation detector based on silicon carbide. All the detector components were considered for an application in a high temperature environment like a nuclear reactor core. The radiation response, especially to alpha particles, was measured using an (241)Am source at variable operating voltages at room temperature in the air. The temperature on detector was controlled from 30°C to 250°C. The alpha-particle spectra were measured at zero bias operation. Even though the detector is operated at high temperature, the energy resolution as a function of temperature is almost constant within 3.5% deviation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characterization of CdZnTe ambient temperature detectors

International Nuclear Information System (INIS)

Lavietes, A.

1994-09-01

A great deal of interest has been generated in the use of cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) detectors for ambient temperature detection of radionuclides. The addition of zinc to CdTe provides several benefits that enhance the materials operational characteristics at ambient temperature. Recent movement in the industry is to produce larger volume detectors using CdZnTe without much known about the effects of larger geometry on performance. The purpose of this study is to get an idea of the relationship of detector performance to both area and thickness variations

Prototype of high resolution PET using resistive electrode position sensitive CdTe detectors

International Nuclear Information System (INIS)

Kikuchi, Yohei; Ishii, Keizo; Matsuyama, Shigeo; Yamazaki, Hiromichi

2008-01-01

Downsizing detector elements makes it possible that spatial resolutions of positron emission tomography (PET) cameras are improved very much. From this point of view, semiconductor detectors are preferable. To obtain high resolution, the pixel type or the multi strip type of semiconductor detectors can be used. However, in this case, there is a low packing ratio problem, because a dead area between detector arrays cannot be neglected. Here, we propose the use of position sensitive semiconductor detectors with resistive electrode. The CdTe detector is promising as a detector for PET camera because of its high sensitivity. In this paper, we report development of prototype of high resolution PET using resistive electrode position sensitive CdTe detectors. We made 1-dimensional position sensitive CdTe detectors experimentally by changing the electrode thickness. We obtained 750 A as an appropriate thickness of position sensitive detectors, and evaluated the performance of the detector using a collimated 241 Am source. A good position resolution of 1.2 mm full width half maximum (FWHM) was obtained. On the basis of the fundamental development of resistive electrode position sensitive detectors, we constructed a prototype of high resolution PET which was a dual head type and was consisted of thirty-two 1-dimensional position sensitive detectors. In conclusion, we obtained high resolutions which are 0.75 mm (FWHM) in transaxial, and 1.5 mm (FWHM) in axial. (author)

Characterization and Calibration of Large Area Resistive Strip Micromegas Detectors

CERN Document Server

Losel, Philipp Jonathan; The ATLAS collaboration

2015-01-01

Resisitve strip Micromegas detectors behave discharge tolerant. They have been tested extensively as smaller detectors of about 10 x 10 cm$^2$ in size and they work reliably at high rates of 100\\,kHz/cm$^2$ and above. Tracking resolutions well below 100\\,$\\mu$m have been observed for 100 GeV muons and pions. Micromegas detectors are meanwhile proposed as large area muon precision trackers of 2-3\\,m$^2$ in size. To investigate possible differences between small and large detectors, a 1\\,m$^2$ detector with 2048 resistive strips at a pitch of 450 $\\mu$m was studied in the LMU Cosmic Ray Facility (CRF) using two 4 $\\times$ 2.2 m$^2$ large Monitored Drift Tube (MDT) chambers for cosmic muon reference tracking. Segmentation of the resistive strip anode plane in 57.6\\,mm x 95\\,mm large areas has been realized by the readout of 128 strips with one APV25 chip each and by 11 95\\,mm broad trigger scintillators placed along the readout strips.\\\\ This allows for mapping of homogenity in pulse height and efficiency, deter...

Detector Physics of Resistive Plate Chambers

CERN Document Server

Lippmann, Christian; Riegler, W

2003-01-01

Resistive Plate Chambers (RPCs) are gaseous parallel plate avalanche detectors that implement electrodes made from a material with a high volume resistivity between 10^7 and 10^12 Ohm cm. Large area RPCs with 2mm single gaps operated in avalanche mode provide above 98% efficiency and a time resolution of around 1ns up to a flux of several kHz/cm2. These Trigger RPCs will, as an example, equip the muon detector system of the ATLAS experiment at CERN on an area of 3650m2 and with 355.000 independent read out channels. Timing RPCs with a gas gap of 0.2 to 0.3mm are widely used in multi gap configurations and provide 99% efficiency and time resolution down to 50ps. While their performance is comparable to existing scintillator-based Time-Of-Flight (TOF) technology, Timing RPCs feature a significantly, up to an order of magnitude, lower price per channel. They will for example equip the 176m2 TOF barrel of the ALICE experiment at CERN with 160.000 independent read out cells. RPCs were originally operated in stream...

A study on heat resistance of high temperature resistant coating

Energy Technology Data Exchange (ETDEWEB)

Zhang, Liping; Wang, Xueying; Zhang, Qibin; Qin, Yanlong; Lin, Zhu [Research Institute of Engineering Technology of CNPC, Tianjin (China)

2005-04-15

A high temperature resistant coating has been developed, which is mainly for heavy oil production pipes deserved the serious corrosion. The coating has excellent physical and mechanical performance and corrosion resistance at room and high temperature. In order to simulate the underground working condition of heavy oil pipes,the heat resistance of the high temperature resistant coating has been studied. The development and a study on the heat resistance of the DHT high temperature resistance coating have been introduced in this paper

A study on heat resistance of high temperature resistant coating

International Nuclear Information System (INIS)

Zhang, Liping; Wang, Xueying; Zhang, Qibin; Qin, Yanlong; Lin, Zhu

2005-01-01

A high temperature resistant coating has been developed, which is mainly for heavy oil production pipes deserved the serious corrosion. The coating has excellent physical and mechanical performance and corrosion resistance at room and high temperature. In order to simulate the underground working condition of heavy oil pipes,the heat resistance of the high temperature resistant coating has been studied. The development and a study on the heat resistance of the DHT high temperature resistance coating have been introduced in this paper

The resistive plate WELL detector as a single stage thick gaseous multiplier detector

Energy Technology Data Exchange (ETDEWEB)

Bressler, Shikma; Breskin, Amos; Moleri, Luca; Kumar, Ashwini; Pitt, Michael [Department of Particle Physics and Astrophysics, Weizmann Institute of Science (WIS) (Israel); Kudella, Simon [Institut fuer Experimentelle Kernphysik (IEKP), KIT (Germany)

2015-07-01

Gaseous Electron Multiplier (GEM) detector use high electric fields inside the h ole of a foil to achieve a high charge multiplication. As a thicker version of G EMs based on printed circuit board (PCB) structures, Thick Gaseous Electron Multiplier (THGEM) detectors combine the high gain of a GEM foil with the robustness, stability and low production costs of a PCB and allow a large quantity of applications that require the coverage of a large area at low cost and moderate spatial resolution. One application the Weizmann Institute of Science (WIS) develops as a member of the RD51 framework is the Resistive Plate WELL (RPWELL) detector. This single stage detector allows a very stable, discharge free operation at high gain (10{sup 5}). The single stage operation allows a low total height and make s the RPWELL a candidate for the Digital Hadronic Calorimeter (DHCAL) of the International Large Detector (ILD) at the International Linear Collider (ILC). The talk gives an insight into the way the RPWELL works and shows results from the last test beam.

Graphene-based mid-infrared room-temperature pyroelectric bolometers with ultrahigh temperature coefficient of resistance.

Science.gov (United States)

Sassi, U; Parret, R; Nanot, S; Bruna, M; Borini, S; De Fazio, D; Zhao, Z; Lidorikis, E; Koppens, F H L; Ferrari, A C; Colli, A

2017-01-31

There is a growing number of applications demanding highly sensitive photodetectors in the mid-infrared. Thermal photodetectors, such as bolometers, have emerged as the technology of choice, because they do not need cooling. The performance of a bolometer is linked to its temperature coefficient of resistance (TCR, ∼2-4% K -1 for state-of-the-art materials). Graphene is ideally suited for optoelectronic applications, with a variety of reported photodetectors ranging from visible to THz frequencies. For the mid-infrared, graphene-based detectors with TCRs ∼4-11% K -1 have been demonstrated. Here we present an uncooled, mid-infrared photodetector, where the pyroelectric response of a LiNbO 3 crystal is transduced with high gain (up to 200) into resistivity modulation for graphene. This is achieved by fabricating a floating metallic structure that concentrates the pyroelectric charge on the top-gate capacitor of the graphene channel, leading to TCRs up to 900% K -1 , and the ability to resolve temperature variations down to 15 μK.

Assessment of ambient-temperature, high-resolution detectors for nuclear safeguards applications

International Nuclear Information System (INIS)

Ruhter, W.D.; McQuaid, J.H.; Lavietes, A.

1993-01-01

High-resolution, gamma- and x-ray spectrometry are used routinely in nuclear safeguards verification measurements of plutonium and uranium in the field. These measurements are now performed with high-purity germanium (HPGe) detectors that require cooling liquid-nitrogen temperatures, thus limiting their utility in field and unattended safeguards measurement applications. Ambient temperature semiconductor detectors may complement HPGe detectors for certain safeguards verification applications. Their potential will be determined by criteria such as their performance, commercial availability, stage of development, and costs. We have conducted as assessment of ambient temperature detectors for safeguards measurement applications with these criteria in mind

A monolithically integrated detector-preamplifier on high-resistivity silicon

International Nuclear Information System (INIS)

Holland, S.; Spieler, H.

1990-02-01

A monolithically integrated detector-preamplifier on high-resistivity silicon has been designed, fabricated and characterized. The detector is a fully depleted p-i-n diode and the preamplifier is implemented in a depletion-mode PMOS process which is compatible with detector processing. The amplifier is internally compensated and the measured gain-bandwidth product is 30 MHz with an input-referred noise of 15 nV/√Hz in the white noise regime. Measurements with an Am 241 radiation source yield an equivalent input noise charge of 800 electrons at 200 ns shaping time for a 1.4 mm 2 detector with on-chip amplifier in an experimental setup with substantial external pickup

Neutron radiation damage studies on silicon detectors

International Nuclear Information System (INIS)

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

1990-10-01

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

Application of PSpice circuit simulator in development of resistive plate chamber detector

International Nuclear Information System (INIS)

Wang Yaping; Cai Xu

2008-01-01

An electrical model was presented for resistive plate chamber (RPC) detector. The readout signals of RPC detector were studied with PSpice simulation based on the model. The simulation results show a good agreement with real data and authoritative data. Physical performance of RPC detector can be predicted by the PSpice simulation, so this is an efficient means to optimize RPC detector's research and development. (authors)

Uncertainty Analysis of the Temperature–Resistance Relationship of Temperature Sensing Fabric

Directory of Open Access Journals (Sweden)

Muhammad Dawood Husain

2016-11-01

Full Text Available This paper reports the uncertainty analysis of the temperature–resistance (TR data of the newly developed temperature sensing fabric (TSF, which is a double-layer knitted structure fabricated on an electronic flat-bed knitting machine, made of polyester as a basal yarn, and embedded with fine metallic wire as sensing element. The measurement principle of the TSF is identical to temperature resistance detector (RTD; that is, change in resistance due to change in temperature. The regression uncertainty (uncertainty within repeats and repeatability uncertainty (uncertainty among repeats were estimated by analysing more than 300 TR experimental repeats of 50 TSF samples. The experiments were performed under dynamic heating and cooling environments on a purpose-built test rig within the temperature range of 20–50 °C. The continuous experimental data was recorded through LabVIEW-based graphical user interface. The result showed that temperature and resistance values were not only repeatable but reproducible, with only minor variations. The regression uncertainty was found to be less than ±0.3 °C; the TSF sample made of Ni and W wires showed regression uncertainty of <±0.13 °C in comparison to Cu-based TSF samples (>±0.18 °C. The cooling TR data showed considerably reduced values (±0.07 °C of uncertainty in comparison with the heating TR data (±0.24 °C. The repeatability uncertainty was found to be less than ±0.5 °C. By increasing the number of samples and repeats, the uncertainties may be reduced further. The TSF could be used for continuous measurement of the temperature profile on the surface of the human body.

Science with low temperature detectors

International Nuclear Information System (INIS)

Sadoulet, B.; Lawrence Berkeley National Lab., CA; California Univ., Berkeley

1996-01-01

The novel technique of particle detection with low temperature detectors opens a number of new scientific opportunities. We review some of these, focusing on three generic applications: far infrared bolometry taking as an example the cosmic microwave background, X-ray spectroscopy for astrophysics and biological applications, and massive calorimeters for dark matter searches and neutrino physics. (orig.)

Development of electron temperature measuring system by silicon drift detector

International Nuclear Information System (INIS)

Song Xianying; Yang Jinwei; Liao Min

2007-12-01

Soft X-ray spectroscopy with two channels Silicon Drift Detector (SDD) are adopted for electron temperature measuring on HL-2A tokamak in 2005. The working principle, design and first operation of the SDD soft X-ray spectroscopy are introduced. The measuring results of electron temperature are also presented. The results show that the SDD is very good detector for electron temperature measuring on HL-2A tokamak. These will become a solid basic work to establish SDD array for electron temperature profiling. (authors)

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...

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

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

International Nuclear Information System (INIS)

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

2009-01-01

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

Processing and first characterization of detectors made with high resistivity n- and p-type Czochralski silicon

International Nuclear Information System (INIS)

Bruzzi, M.; Bisello, D.; Borrello, L.; Borchi, E.; Boscardin, M.; Candelori, A.; Creanza, D.; Dalla Betta, G.-F.; DePalma, M.; Dittongo, S.; Focardi, E.; Khomenkov, V.; Litovchenko, A.; Macchiolo, A.; Manna, N.; Menichelli, D.; Messineo, A.; Miglio, S.; Petasecca, M.; Piemonte, C.; Pignatel, G.U.; Radicci, V.; Ronchin, S.; Scaringella, M.; Segneri, G.; Sentenac, D.; Tosi, C.; Zorzi, N.

2005-01-01

We report on the design, manufacturing and first characterisation of pad diodes, test structures and microstrip detectors processed with high resistivity magnetic Czochralski (MCz) p- and n-type Si. The pre-irradiation study on newly processed microstrip detectors and test structures show a good overall quality of the processed wafers. After irradiation with 24 GeV/c protons up to 4x10 14 cm -2 the characterisation of n-on-p and p-on-n MCz Si sensors with the C-V method show a decrease of the full depletion voltage and no space charge sign inversion. Microscopic characterisation has been performed to study the role of thermal donors in Czochralski Si. No evidence of thermal donor activation was observed in n-type MCz Si detectors if contact sintering was performed at a temperature lower than 380 deg. C and the final passivation oxide was omitted

Impulse method for temperature measurement of silicon detectors

International Nuclear Information System (INIS)

Kushpil, V.V.; Kushpil, S.A.; Petracek, V.

1999-01-01

A new impulse method of temperature measurement based on switching characteristic of the P-N junction is described. Temperature of silicon detector can be determined, due to the strong temperature dependence of minority carrier lifetime, from the charge registered during the switching-off process. The method has been tested in temperature range 25 - 60 deg C. Advantages, drawbacks and precision of this method are discussed

Calorimetric low temperature detectors for heavy ion physics

Energy Technology Data Exchange (ETDEWEB)

Egelhof, P.; Kraft-Bermuth, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Mainz Univ. (Germany). Inst. fuer Physik

2005-05-01

Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics at present and at the next generation heavy ion facilities is given with a special emphasis on the conditions for heavy ion detection and the potential advantage of cryogenic detectors for applications in heavy ion physics. Two types of calorimetric low temperature detectors for the detection of energetic heavy ions have been developed and their response to the impact of heavy ions was investigated systematically for a wide range of energies (E=0.1-360 MeV/amu) and ion species ({sup 4}He.. {sup 238}U). Excellent results with respect to energy resolution, {delta}E/E ranging from 1 to 5 x 10{sup -3} even for the heaviest ions, and other basic detector properties such as energy linearity with no indication of a pulse height defect, energy threshold, detection efficiency and radiation hardness have been obtained, representing a considerable improvement as compared to conventional heavy ion detectors based on ionization. With the achieved performance, calorimetric low temperature detectors bear a large potential for applications in various fields of basic and applied heavy ion research. A brief overview of a few prominent examples, such as high resolution nuclear spectroscopy, high resolution nuclear mass determination, which may be favourably used for identification of superheavy elements or in direct reaction experiments with radioactive beams, as well as background discrimination in accelerator mass spectrometry, is given, and first results are presented. For instance, the use of cryogenic detectors allowed to improve the sensitivity in trace analysis of {sup 236}U by one order of magnitude and to determine the up to date smallest isotope ratio of {sup 236}U/{sup 238}U = 6.1 x 10{sup -12} in a sample of natural uranium. Besides the detection of heavy ions, the concept of cryogenic detectors also

Calorimetric low temperature detectors for heavy ion physics

International Nuclear Information System (INIS)

Egelhof, P.; Kraft-Bermuth, S.; Mainz Univ.

2005-07-01

Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics at present and at the next generation heavy ion facilities is given with a special emphasis on the conditions for heavy ion detection and the potential advantage of cryogenic detectors for applications in heavy ion physics. Two types of calorimetric low temperature detectors for the detection of energetic heavy ions have been developed and their response to the impact of heavy ions was investigated systematically for a wide range of energies (E=0.1-360 MeV/amu) and ion species ( 4 He.. 238 U). Excellent results with respect to energy resolution, ΔE/E ranging from 1 to 5 x 10 -3 even for the heaviest ions, and other basic detector properties such as energy linearity with no indication of a pulse height defect, energy threshold, detection efficiency and radiation hardness have been obtained, representing a considerable improvement as compared to conventional heavy ion detectors based on ionization. With the achieved performance, calorimetric low temperature detectors bear a large potential for applications in various fields of basic and applied heavy ion research. A brief overview of a few prominent examples, such as high resolution nuclear spectroscopy, high resolution nuclear mass determination, which may be favourably used for identification of superheavy elements or in direct reaction experiments with radioactive beams, as well as background discrimination in accelerator mass spectrometry, is given, and first results are presented. For instance, the use of cryogenic detectors allowed to improve the sensitivity in trace analysis of 236 U by one order of magnitude and to determine the up to date smallest isotope ratio of 236 U/ 238 U = 6.1 x 10 -12 in a sample of natural uranium. Besides the detection of heavy ions, the concept of cryogenic detectors also provides considerable advantage for X

Temperature-compensated pressure detectors and transmitter for use in hostile environment

International Nuclear Information System (INIS)

Di Noia, E.J.; Breunich, T.R.

1984-01-01

A pressure or differential pressure detector suitable for use in a hostile environment, for example, under high pressure, temperature, and radiation conditions in the containment vessel of a nuclear generating plant includes as a transducer a linear variable differential transformer (LVDT) disposed within a detector housing designed to withstand temperatures of about 260 deg C. A signal detecting and conditioning circuit remote from the detector housing includes a demodulator for producing X and Y demodulated signals respectively from A and B secondary windings of the LVDT, a summing circuit for producing a temperature analog voltage X + Y, a subtractor for providing a differential pressure analog voltage X - Y, and a multiplier for multiplying the differential pressure analog voltage X - Y by a temperature compensation voltage X + Y - Ref based on the temperature analog voltage to provide a resulting temperature-compensated differential pressure analog signal. (author)

Temperature cycling test of planar hyper-pure germanium radiation detector

International Nuclear Information System (INIS)

Sakai, Eiji

1976-01-01

If a Ge (Li) detector is left at the normal temperature, generally it does not recover its original performance even when it is cooled again with liquid nitrogen, as Li ions in the compensated i zone precipitate by Li drift and it returns to p type which is the state before drift. One of the devices that overcomes this shortcoming is the p-n junction Ge detector, which required the production of high purity Ge single crystals to obtain the thick depletion layer. The planar or coaxial type detectors were produced using the Ge single crystals with impurity concentration of 10 10 /cm 3 and it was recognized that they showed the gamma detecting characteristic nearly equal to Ge (Li) detectors. They are now commercially available from a few companies. The author carried out the temperature-cycling test of the planar type hyperpure Ge detector sold by Nuclear Radiation Developments, Canada. First, applying liquid nitrogen, the leakage current, static capacity, gamma ray-detecting efficiency and energy resolution were measured. Then it was returned to room temperature. Since then, irregular cycling tests were carried out 15 times. The results didn't show any significant change in the gamma ray-detecting efficiency, energy resolution and static capacity. Though leakage current changed between 9.3 and 33 pA, it does not influence on the energy resolution because of small absolute values. It may be said that it is sufficiently stable in the temperature cycling from room temperature to 77 K. (Wakatsuki, Y.)

Signal development in irradiated silicon detectors

CERN Document Server

Kramberger, Gregor; Mikuz, Marko

2001-01-01

This work provides a detailed study of signal formation in silicon detectors, with the emphasis on detectors with high concentration of irradiation induced defects in the lattice. These defects give rise to deep energy levels in the band gap. As a consequence, the current induced by charge motion in silicon detectors is signifcantly altered. Within the framework of the study a new experimental method, Charge correction method, based on transient current technique (TCT) was proposed for determination of effective electron and hole trapping times in irradiated silicon detectors. Effective carrier trapping times were determined in numerous silicon pad detectors irradiated with neutrons, pions and protons. Studied detectors were fabricated on oxygenated and non-oxygenated silicon wafers with different bulk resistivities. Measured effective carrier trapping times were found to be inversely proportional to fuence and increase with temperature. No dependence on silicon resistivity and oxygen concentration was observ...

In-beam evaluation of a medium-size Resistive-Plate WELL gaseous particle detector

CERN Document Server

Moleri, L.

2016-09-27

In-beam evaluation of a fully-equipped medium-size 30$\\times$30 cm$^2$ Resistive Plate WELL (RPWELL) detector is presented. It consists here of a single element gas-avalanche multiplier with Semitron ESD225 resistive plate, 1 cm$^2$ readout pads and APV25/SRS electronics. Similarly to previous results with small detector prototypes, stable operation at high detection efficiency (>98%) and low average pad multiplicity (~1.2) were recorded with 150 GeV muon and high-rate pion beams, in Ne/(5%CH$_4$), Ar/(5%CH$_4$) and Ar/(7%CO$_2$). This is an important step towards the realization of robust detectors suitable for applications requiring large-area coverage; among them Digital Hadron Calorimetry.

A variable temperature cryostat that produces in situ clean-up germanium detector surfaces

International Nuclear Information System (INIS)

Pehl, R.H.; Madden, N.W.; Malone, D.F.; Cork, C.P.; Landis, D.A.; Xing, J.S.; Friesel, D.L.

1988-11-01

Variable temperature cryostats that can maintain germanium detectors at temperatures from 82 K to about 400 K while the thermal shield surrounding the detectors remains much colder when the detectors are warmed have been developed. Cryostats such as these offer the possibility of cryopumping material from the surface of detectors to the colder thermal shield. The diode characteristics of several detectors have shown very significant improvement following thermal cycles up to about 150 K in these cryostats. Important applications for cryostats having this attribute are many. 4 figs

Antibiotic resistance increases with local temperature

Science.gov (United States)

MacFadden, Derek R.; McGough, Sarah F.; Fisman, David; Santillana, Mauricio; Brownstein, John S.

2018-06-01

Bacteria that cause infections in humans can develop or acquire resistance to antibiotics commonly used against them1,2. Antimicrobial resistance (in bacteria and other microbes) causes significant morbidity worldwide, and some estimates indicate the attributable mortality could reach up to 10 million by 20502-4. Antibiotic resistance in bacteria is believed to develop largely under the selective pressure of antibiotic use; however, other factors may contribute to population level increases in antibiotic resistance1,2. We explored the role of climate (temperature) and additional factors on the distribution of antibiotic resistance across the United States, and here we show that increasing local temperature as well as population density are associated with increasing antibiotic resistance (percent resistant) in common pathogens. We found that an increase in temperature of 10 °C across regions was associated with an increases in antibiotic resistance of 4.2%, 2.2%, and 2.7% for the common pathogens Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. The associations between temperature and antibiotic resistance in this ecological study are consistent across most classes of antibiotics and pathogens and may be strengthening over time. These findings suggest that current forecasts of the burden of antibiotic resistance could be significant underestimates in the face of a growing population and climate change4.

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.

The development of gaseous detectors with solid photocathodes for low temperature applications

CERN Document Server

Periale, L.; Iacobaeus, C.; Francke, T.; Lund-Jensen, B.; Pavlopoulos, N.; Picchi, P.; Pietropaolo, F.

2004-01-01

There are several applications and fundamental research areas which require the detection of VUV light at cryogenic temperatures. For these applications we have developed and successfully tested special designs of gaseous detectors with solid photocathodes able to operate at low temperatures: sealed gaseous detectors with MgF2 windows and windowless detectors. We have experimentally demonstrated, that both primary and secondary (due to the avalanche multiplication inside liquids) scintillation lights could be recorded by photosensitive gaseous detectors. The results of this work may allow one to significantly improve the operation of some noble liquid gas TPCs.

The Successful Operation of Hole-type Gaseous Detectors at Cryogenic Temperatures

CERN Document Server

Pereiale, L.; Iacobaeus, C.; Francke, T.; Lund-Jensen, B.; Pavlopoulos, P.; Picchi, P.; Pietropaolo, F.; Tokanai, F.

2004-01-01

We have demonstrated that hole-type gaseous detectors, GEMs and capillary plates, can operate up to 77 K. For example, a single capillary plate can operate at gains of above 10E3 in the entire temperature interval between 300 until 77 K. The same capillary plate combined with CsI photocathodes could operate perfectly well at gains (depending on gas mixtures) of 100-1000. Obtained results may open new fields of applications for capillary plates as detectors of UV light and charge particles at cryogenic temperatures: noble liquid TPCs, WIMP detectors or LXe scintillating calorimeters and cryogenic PETs.

Equivalent network for resistance and temperature coefficient of resistance versus temperature and composition of thick resistive films

International Nuclear Information System (INIS)

Kusy, A.

1987-01-01

Two types of elementary resistances in thick resistive films have been considered: (i) constriction resistance R/sub C/ determined by the bulk properties of conducting material and by the geometry of constriction, and (ii) barrier resistance R/sub B/ determined by the parameters of a thermally activated type of tunneling process and by the geometry of the metal-insulator-metal unit. On this basis a resistance network composed of a large number of the two types of resistances has been defined. The network has been considered as being equivalent to thick resistive film (TRF) from the point of view of the resistance and temperature coefficient of resistance (TCR). The parameters of this network have been evaluated by the computer-aided approximation of the experimental data found for RuO 2 -based TRFs. On the basis of the equations derived for the network as well as the results of the approximation process, it can be concluded that the small values of the network TCR result from the superposition of the TCR of the conducting component β/sub C/ and of the temperature coefficient of barrier resistance α/sub B/. In this superposition β/sub C/ is attenuated (by 1--2 orders of magnitude), while α/sub B/ is attenuated by only few percentages. The network has been found to be strongly barrier dominated

Room temperature performance of mid-wavelength infrared InAsSb nBn detectors

Energy Technology Data Exchange (ETDEWEB)

Soibel, Alexander; Hill, Cory J.; Keo, Sam A.; Hoglund, Linda; Rosenberg, Robert; Kowalczyk, Robert; Khoshakhlagh, Arezou; Fisher, Anita; Ting, David Z.-Y.; Gunapala, Sarath D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91030 (United States)

2014-07-14

In this work, we investigate the high temperature performance of mid-wavelength infrared InAsSb-AlAsSb nBn detectors with cut-off wavelengths near 4.5 μm. The quantum efficiency of these devices is 35% without antireflection coatings and does not change with temperature in the 77–325 K temperature range, indicating potential for room temperature operation. The current generation of nBn detectors shows an increase of operational bias with temperature, which is attributed to a shift in the Fermi energy level in the absorber. Analysis of the device performance shows that operational bias and quantum efficiency of these detectors can be further improved. The device dark current stays diffusion limited in the 150 K–325 K temperature range and becomes dominated by generation-recombination processes at lower temperatures. Detector detectivities are D*(λ) = 1 × 10{sup 9} (cm Hz{sup 0.5}/W) at T = 300 K and D*(λ) = 5 × 10{sup 9} (cm Hz{sup 0.5}/W) at T = 250 K, which is easily achievable with a one stage TE cooler.

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

International Nuclear Information System (INIS)

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

1998-01-01

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

One-cm-thick Si detector at LHe temperature

Energy Technology Data Exchange (ETDEWEB)

Braggio, C. [Dipartimento di Fisica, Universita di Ferrara, Via Saragat 1, 44100 Ferrara (Italy)], E-mail: braggio@pd.infn.it; Bressi, G. [INFN, Sez. di Pavia, Via Bassi 6, 27100 Pavia (Italy); Carugno, G. [INFN, Sez. di Padova, Via Marzolo 8, 35131 Padova (Italy); Galeazzi, G. [Laboratori Nazionali di Legnaro, Via dell' Universita 1, 35020 Legnaro (Italy); Serafin, A. [Dipartimento di Fisica, Universita di Padova, Via Marzolo 8, 35131 Padova (Italy)

2007-10-11

A silicon p-i-n diode of thickness 1 cm has been studied experimentally at liquid helium temperature. This preliminary study is aimed at the construction of a much bigger detector to detect low energy neutrino events.

One-cm-thick Si detector at LHe temperature

International Nuclear Information System (INIS)

Braggio, C.; Bressi, G.; Carugno, G.; Galeazzi, G.; Serafin, A.

2007-01-01

A silicon p-i-n diode of thickness 1 cm has been studied experimentally at liquid helium temperature. This preliminary study is aimed at the construction of a much bigger detector to detect low energy neutrino events

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

Characterization of Titanium films for low temperature detectors

Science.gov (United States)

Monticone, E.; Rajteri, M.; Rastello, M. L.; Lacquaniti, V.; Gandini, C.; Pasca, E.; Ventura, G.

2002-02-01

In this work we study Ti films, with thickness between 10 nm and 1000 nm, deposited by e-gun on silicon nitride. Critical temperatures and electrical resistivities of these films have been measured and related each other. The behavior of critical temperatures versus the residual resistivities is discussed in the frame of the Testardi and Mattheiss theory .

SQUIDs in thermal detectors of weakly interacting particles

International Nuclear Information System (INIS)

Trofimov, V.N.

1991-01-01

The application of four different types of SQUID-assisted thermometers for cryogenic thermal detectors of weakly interacting particles is analyzed with two of them for the first time. The classic resistive thermometer is considered as well for the comparison. Original results of testing the detector with working temperature of 1K and thermocouple thermometer with SQUID are given. The conclusion is made that temperature resolution of 10 -10 kHz -1/2 or energy sensitivity of 1-10 eV per 1 kg of detector mass can be achieved when using the SQUID-assisted thermometers. 12 refs.; 7 figs.; 1 tab

Detectors for Tomorrow's Instruments

Science.gov (United States)

Moseley, Harvey

2009-01-01

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

High-operating temperature MWIR photon detectors based on type II InAs/GaSb superlattice

Science.gov (United States)

Razeghi, Manijeh; Nguyen, Binh-Minh; Delaunay, Pierre-Yves; Abdollahi Pour, Siamak; Huang, Edward Kwei-wei; Manukar, Paritosh; Bogdanov, Simeon; Chen, Guanxi

2010-01-01

Recent efforts have been paid to elevate the operating temperature of Type II InAs/GaSb superlattice Mid Infrared photon detectors. Optimized growth parameters and interface engineering technique enable high quality material with a quantum efficiency above 50%. Intensive study on device architecture and doping profile has resulted in almost one order of magnitude of improvement to the electrical performance and lifted up the 300K-background BLIP operation temperature to 166K. At 77K, the ~4.2 μm cut-off devices exhibit a differential resistance area product in excess of the measurement system limit (106 Ohm.cm2) and a detectivity of 3x1013cm.Hz1/2/W. High quality focal plane arrays were demonstrated with a noise equivalent temperature of 10mK at 77K. Uncooled camera is capable to capture hot objects such as soldering iron.

Development and application of nuclear radiation detector made from high resistivity silicon and compound semiconductor

International Nuclear Information System (INIS)

Ding Honglin; Zhang Xiufeng; Zhang Wanchang; Li Jiang

1995-11-01

The development of high resistivity silicon detectors and compound semiconductor detectors as well as their application in nuclear medicine are described. It emphasizes on several key techniques in fabricating detectors in order to meet their application in nuclear medicine. As for a high resistivity silicon detector, its counting rate to 125 I 28.5 keV X-ray has to be improved. So employing a conic mesa structure can increase the thickness of samples, and can raise the electric field of collecting charges under the same bias voltage. As for a GaAs detector, its performance of collecting charges has to be improved. So the thicknesses of GaAs samples are decreased and proper thermal treatment to make Ni-Ge-Au ohmic contacts are employed. Applying a suitable reverse bias voltage can obtain a fully depleted detector, and can obtain a lower forward turn-on voltage and a thinner weak electric field region. After resolving these key techniques, the performance of GaAs detectors has been distinctly improved. The count rate to 125 I X-ray has increased by three or five times under the same testing condition and background circumstance (2 refs., 8 figs., 3 tabs.)

Imaging microchannel plate detectors for XUV sky survey experiments

International Nuclear Information System (INIS)

Barstow, M.A.; Fraser, G.W.; Milward, S.R.

1986-01-01

Attention is given to the development of microchannel plate detectors for the Wide Field Camera (WFC) XUV (50-300 A) sky survey experiment on Rosat. A novel feature of the detector design is that the microchannel plates and their resistive anode readout are curved to the same radius as the WFC telescope focal surface. It is shown that curving the channel plates is not detrimental to gain uniformity. The paper describes the design of a curved resistive anode readout element and contrasts the present measurements of spatial resolution, global and local uniformity and temperature coefficient of resistance with the poor performance recently ascribed to resistive anodes in the literature. 18 references

Detection of 14 MeV neutrons in high temperature environment up to 500 deg. C using 4H-SiC based diode detector

Energy Technology Data Exchange (ETDEWEB)

Szalkai, D.; Klix, A. [KIT- Karlsruhe Institute of Technology, Institute of Neutron Physics and Reactor Technology Karlsruhe 76344 (Germany); Ferone, R.; Issa, F.; Ottaviani, L.; Vervisch, V. [IM2NP, UMR CNRS 7334, Aix-Marseille University, Case 231 -13397 Marseille Cedex 20 (France); Gehre, D. [Inst. for Nucl.- and Particle-Phys., Dresden University of Technology, Dresden 01069 (Germany); Lyoussi, A. [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 reactor technology and industrial applications detection of fast and thermal neutrons plays a crucial role in getting relevant information about the reactor environment and neutron yield. The inevitable elevated temperatures make neutron yield measurements problematic. Out of the currently available semiconductors 4H-SiC seems to be the most suitable neutron detector material under extreme conditions due to its high heat and radiation resistance, large band-gap and lower cost of production than in case of competing diamond detectors. In the framework of the European I-Smart project, optimal {sup 4}H-SiC diode geometries were developed for high temperature neutron detection and have been tested with 14 MeV fast neutrons supplied by a deuterium-tritium neutron generator with an average neutron flux of 10{sup 10}-10{sup 11} n/(s*cm{sup 2}) at Neutron Laboratory of the Technical University of Dresden in Germany from room temperatures up to several hundred degrees Celsius. Based on the results of the diode measurements, detector geometries appear to play a crucial role for high temperature measurements up to 500 deg. C. Experimental set-ups using SiC detectors were constructed to simulate operation in the harsh environmental conditions found in the tritium breeding blanket of the ITER fusion reactor, which is planned to be the location of neutron flux characterization measurements in the near future. (authors)

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)

Advanced radiation detector development: Advanced semiconductor detector development: Development of a oom-temperature, gamma ray detector using gallium arsenide to develop an electrode detector

International Nuclear Information System (INIS)

Knoll, G.F.

1995-11-01

The advanced detector development project at the University of Michigan has completed the first full year of its current funding. Our general goals are the development of radiation detectors and spectrometers that are capable of portable room temperature operation. Over the past 12 months, we have worked primarily in the development of semiconductor spectrometers with open-quotes single carrierclose quotes response that offer the promise of room temperature operation and good energy resolution in gamma ray spectroscopy. We have also begun a small scale effort at investigating the properties of a small non-spectroscopic detector system with directional characteristics that will allow identification of the approximate direction in which gamma rays are incident. These activities have made use of the extensive clean room facilities at the University of Michigan for semiconductor device fabrication, and also the radiation measurement capabilities provided in our laboratory in the Phoenix Building on the North Campus. In addition to our laboratory based activities, Professor Knoll has also been a participant in several Department of Energy review activities held in the Forrestal Building and at the Germantown site. The most recent of these has been service on a DOE review panel chaired by Dr. Hap Lamonds that is reviewing the detector development programs supported through the Office of Arms Control and International Security

A Study of the Operation of Especially Designed Photosensitive Gaseous Detectors at Cryogenic Temperatures

CERN Document Server

Periale, L; Lund-Jensen, B; Pavlopoulos, P; Peskov, Vladimir; Picchi, P; Pietropaolo, F

2006-01-01

In some experiments and applications there is need for large-area photosensitive detectors to operate at cryogenic temperatures. Nowadays, vacuum PMs are usually used for this purpose. We have developed special designs of planar photosensitive gaseous detectors able to operate at cryogenic temperatures. Such detectors are much cheaper PMs and are almost insensitive to magnetic fields. Results of systematic measurements of their quantum efficiencies, the maximum achievable gains and long-term stabilities will be presented. The successful operation of these detectors open realistic possibilities in replacing PMs by photosensitive gaseous detectors in some applications dealing with cryogenic liquids; for example in experiments using noble liquid TPCs or noble liquid scintillating calorimeters.

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.

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.

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.

Low-temperature technique of thin silicon ion implanted epitaxial detectors

Energy Technology Data Exchange (ETDEWEB)

Kordyasz, A.J.; Bednarek, A. [Warsaw University, Heavy Ion Laboratory, Warsaw (Poland); Le Neindre, N.; Bougault, R.; Lopez, O.; Merrer, Y.; Vient, E. [Universite de Caen, LPC, IN2P3-CNRS, ENSICAEN, Caen-Cedex (France); Parlog, M. [Universite de Caen, LPC, IN2P3-CNRS, ENSICAEN, Caen-Cedex (France); ' ' Horia Hulubei' ' National Institute of Physics and Nuclear Engineering (IFIN-HH), Bucharest Magurele (Romania); Casini, G.; Poggi, G.; Bini, M.; Valdre, S.; Scarlini, E.; Pasquali, G.; Pastore, G.; Piantelli, S.; Stefanini, A.; Olmi, A.; Barlini, S. [INFN Firenze, Sesto Fiorentino (Italy); Universita di Firenze, Sesto Fiorentino (Firenze) (Italy); Kowalczyk, M. [Warsaw University, Heavy Ion Laboratory, Warsaw (Poland); University of Warsaw, Institute of Experimental Physics, Warsaw (Poland); Frankland, J.D.; Bonnet, E.; Chbihi, A.; Gruyer, D. [CEA et IN2P3-CNRS, GANIL, Caen-Cedex 05 (France); Borderie, B.; Ademard, G.; Edelbruck, P.; Rivet, M.F.; Salomon, F. [IN2P3-CNRS, Institut de Physique Nucleaire, Orsay-Cedex (France); Boiano, A.; Rosato, E.; Meoli, A.; Ordine, A.; Spadaccini, G.; Tortone, G.; Vigilante, M.; Vanzanella, E. [Universita di Napoli ' ' Federico II' ' , Dipartimento di Scienze Fisiche, Napoli (Italy); INFN, Napoli (Italy); Bruno, M.; Serra, S.; Morelli, L.; Guerzoni, M. [INFN, Bologna (Italy); Universita di Bologna, Bologna (Italy); Alba, R.; Santonocito, D.; Maiolino, C. [INFN, Catania (Italy); Universita di Catania, LNS, Catania (Italy); Cinausero, M.; Gramegna, F.; Marchi, T. [INFN LNL Legnaro, Legnaro (Padova) (Italy); Kozik, T.; Kulig, P.; Twarog, T.; Sosin, Z. [Jagiellonian University, Cracow (Poland); Gasior, K.; Grzeszczuk, A.; Zipper, W. [University of Silesia, Silesian University, Katowice (Poland); Sarnecki, J.; Lipinski, D.; Wodzinska, H.; Brzozowski, A.; Teodorczyk, M.; Gajewski, M.; Zagojski, A.; Krzyzak, K. [Institute of Electronic Materials Technology, Warsaw (Poland); Tarasiuk, K.J. [University of Warsaw, Institute of Experimental Physics, Warsaw (Poland); Khabanowa, Z. [Faculty of Physics, Warsaw University of Technology, Warsaw (Poland); Kordyasz, L. [Warsaw University of Technology, Faculty of Mechatronics, Institute of Mikromechanics and Photonics, Department of Design of Precision Devices, Warsaw (Poland)

2015-02-01

A new technique of large-area thin ion implanted silicon detectors has been developed within the R and D performed by the FAZIA Collaboration. The essence of the technique is the application of a low-temperature baking process instead of high-temperature annealing. This thermal treatment is performed after B{sup +} ion implantation and Al evaporation of detector contacts, made by using a single adjusted Al mask. Extremely thin silicon pads can be therefore obtained. The thickness distribution along the X and Y directions was measured for a prototype chip by the energy loss of α-particles from {sup 241}Am (left angle E{sub α} right angle = 5.5 MeV). Preliminary tests on the first thin detector (area ∼ 20 x 20 mm{sup 2}) were performed at the INFN-LNS cyclotron in Catania (Italy) using products emitted in the heavy-ion reaction {sup 84}Kr (E = 35 A MeV) + {sup 112}Sn. The ΔE - E ion identification plot was obtained using a telescope consisting of our thin ΔE detector (21 μm thick) followed by a typical FAZIA 510 μm E detector of the same active area. The charge distribution of measured ions is presented together with a quantitative evaluation of the quality of the Z resolution. The threshold is lower than 2 A MeV depending on the ion charge. (orig.)

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

Energy Technology Data Exchange (ETDEWEB)

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

2015-06-01

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

Neutrinos, dark matter and low temperature detectors

International Nuclear Information System (INIS)

Gonzalez-Mestres, L.; Perret-Gallix, D.

1988-01-01

The present status of cryogenic detector developments for particle physics is discussed, with emphasis on applications at the cross-disciplinary frontier between particle physics and astrophysics, where low temperature devices appear to be particularly well suited. The overwiew of results is completed by a sketch of new ideas and possible ways for further improvements. Neutrino role importance is particularly shown

High temperature resistant cermet and ceramic compositions

Science.gov (United States)

Phillips, W. M. (Inventor)

1978-01-01

Cermet compositions having high temperature oxidation resistance, high hardness and high abrasion and wear resistance, and particularly adapted for production of high temperature resistant cermet insulator bodies are presented. The compositions are comprised of a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Also disclosed are novel ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride.

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).

High-temperature abnormal behavior of resistivities for Bi-In melts

International Nuclear Information System (INIS)

Xi Yun; Zu Fangqiu; Li Xianfen; Yu Jin; Liu Lanjun; Li Qiang; Chen Zhihao

2004-01-01

The patterns of electrical resistivities versus temperature in large temperature range have been studied, using the D.C. four-probe method, for liquid Bi-In alloys (Bi-In(33 wt%), Bi-In(38 wt%), Bi-In(50.5 wt%), Bi-In(66 wt%)). The clear turning point of each resistivity-temperature curves of the liquid Bi-In alloys is observed at the temperature much above the melting point, in which temperature range the resistivity-temperature coefficient increases rapidly. Except for the turning temperature range, the resistivities of Bi-In alloys increase linearly with temperature. Because resistivity is sensitive to the structure, this experiment shows the structural transition in Bi-In melts at the temperature much higher than the liquidus. And it is suggested that there are different Bi-In short-range orderings in different Bi-In melts, so the resistivity-temperature curves have the turns at different temperatures and the resistivity-temperature coefficients are also different

Using electrical resistance tomography to map subsurface temperatures

Science.gov (United States)

Ramirez, Abelardo L.; Chesnut, Dwayne A.; Daily, William D.

1994-01-01

A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations.

Using electrical resistance tomography to map subsurface temperatures

Science.gov (United States)

Ramirez, A.L.; Chesnut, D.A.; Daily, W.D.

1994-09-13

A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations. 1 fig.

Peltier battery thermostat for semiconductor detectors

International Nuclear Information System (INIS)

Caini, V.

1980-01-01

The description is given of a Peltier battery cooling thermostat for semiconductor detectors, whose sensing element is the detector itself. A signal proportional to the leakage current is amplified and compared with a chosen reference voltage. The difference, amplified and sensed, regulates the cooling current to the Peltier battery. Special mechanical devices speed up measurement-taking. The leakage current proved to be reducible to as little as 1/1000 of that at ambient temperature and the stabilization obtained is between +-5 nA (although between +-1 nA is also feasible). Hence it is possible to use very high load resistance preamplifiers to reduce noise and to improve stability and pulse height resolution in α spectroscopy, even with a detector unsuitable for work at very low temperatures. Other applications can be foreseen. (orig.)

Mechanism of high-temperature resistant water-base mud

Energy Technology Data Exchange (ETDEWEB)

Luo, P

1981-01-01

Based on experiments, the causes and laws governing the changes in the performance of water-base mud under high temperature are analyzed, and the requisites and mechanism of treating agents resisting high temperature are discussed. Ways and means are sought for inhibiting, delaying and making use of the effect of high temperature on the performance of mud, while new ideas and systematic views have been expressed on the preparation of treating agents and set-up of a high temperature resistant water-base mud system. High temperature dispersion and high temperature surface inactivation of clay in the mud, as well as their effect and method of utilization are reviewed. Subjects also touched upon include degradation and cross-linking of the high-temperature resistant treating agents, their use and effect. Based on the above, the preparation of a water-base and system capable of resisting 180 to 250/sup 0/C is recommended.

Fabrication of detectors and transistors on high-resistivity silicon

International Nuclear Information System (INIS)

Holland, S.

1988-06-01

A new process for the fabrication of silicon p-i-n diode radiation detectors is described. The utilization of backside gettering in the fabrication process results in the actual physical removal of detrimental impurities from critical device regions. This reduces the sensitivity of detector properties to processing variables while yielding low diode reverse-leakage currents. In addition, gettering permits the use of processing temperatures compatible with integrated-circuit fabrication. P-channel MOSFETs and silicon p-i-n diodes have been fabricated simultaneously on 10 kΩ/centerreverse arrowdot/cm silicon using conventional integrated-circuit processing techniques. 25 refs., 5 figs

Room temperature X- and gamma-ray detectors using thallium bromide crystals

CERN Document Server

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

1999-01-01

Thallium bromide (TlBr) is a compound semiconductor with wide band gap (2.68 eV) and high X- and gamma-ray stopping power. The TlBr crystals were grown by the horizontal travelling molten zone (TMZ) method using purified material. Two types of room temperature X- and gamma-ray detectors were fabricated from the TlBr crystals: TlBr detectors with high detection efficiency for positron annihilation gamma-ray (511 keV) detection and TlBr detectors with high-energy resolution for low-energy X-ray detection. The detector of the former type demonstrated energy resolution of 56 keV FWHM (11%) for 511 keV gamma-rays. Energy resolution of 1.81 keV FWHM for 5.9 keV was obtained from the detector of the latter type. In order to analyze noise characteristics of the detector-preamplifier assembly, the equivalent noise charge (ENC) was measured as a function of the amplifier shaping time for the high-resolution detector. This analysis shows that parallel white noise and 1/f noise were dominant noise sources in the detector...

High temperature resistant nanofiber by bubbfil-spinning

Directory of Open Access Journals (Sweden)

Li Ya

2015-01-01

Full Text Available Heat-resisting nanofibers have many potential applications in various industries, and the bubbfil spinning is the best candidate for mass-production of such materials. Polyether sulfone/zirconia solution with a bi-solvent system is used in the experiment. Experimental result reveals that polyether sulfone/zirconia nanofibers have higher resistance to high temperature than pure polyether sulfone fibers, and can be used as high-temperature-resistant filtration materials.

Performance evaluation of a lossy transmission lines based diode detector at cryogenic temperature.

Science.gov (United States)

Villa, E; Aja, B; de la Fuente, L; Artal, E

2016-01-01

This work is focused on the design, fabrication, and performance analysis of a square-law Schottky diode detector based on lossy transmission lines working under cryogenic temperature (15 K). The design analysis of a microwave detector, based on a planar gallium-arsenide low effective Schottky barrier height diode, is reported, which is aimed for achieving large input return loss as well as flat sensitivity versus frequency. The designed circuit demonstrates good sensitivity, as well as a good return loss in a wide bandwidth at Ka-band, at both room (300 K) and cryogenic (15 K) temperatures. A good sensitivity of 1000 mV/mW and input return loss better than 12 dB have been achieved when it works as a zero-bias Schottky diode detector at room temperature, increasing the sensitivity up to a minimum of 2200 mV/mW, with the need of a DC bias current, at cryogenic temperature.

Resistive gaseous detectors designs, performance, and perspectives

CERN Document Server

Abbrescia, Marcello; Peskov, Vladimir

2018-01-01

This first book to critically summarize the latest achievements and emerging applications within this interdisciplinary topic focuses on one of the most important types of detectors for elementary particles and photons: resistive plate chambers (RPCs). In the first part, the outstanding, international team of authors comprehensively describes and presents the features and design of single and double-layer RPCs before covering more advanced multi-layer RPCs. The second part then focuses on the application of RPCs in high energy physics, materials science, medicine and security. Throughout, the experienced authors adopt a didactic approach, with each subject presented in a simple way, increasing in complexity step by step.

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-07-11

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

Stability of High Temperature Standard Platinum Resistance Thermometers at High Temperatures

OpenAIRE

Y. A. ABDELAZIZ; F. M. MEGAHED

2010-01-01

An investigation of the stability of high temperature standard platinum resistance thermometers HTSPRTs has been carried out for two different designs thermometers (with nominal resistance 0.25 Ω and 2.5 Ω) from two different suppliers. The thermometers were heated for more than 160 hours at temperatures above 960 0C using a vertical furnace with a ceramic block. A study was made of the influence of the heat treatment on the stability of the resistance at the triple point of water, and on the...

Estimation of interface resistivity in bonded Si for the development of high performance radiation detectors

International Nuclear Information System (INIS)

Kanno, Ikuo; Yamashita, Makoto; Nomiya, Seiichiro; Onabe, Hideaki

2007-01-01

For the development of high performance radiation detectors, direct bonding of Si wafers would be an useful method. Previously, p-n bonded Si were fabricated and they showed diode characteristics. The interface resistivity was, however, not investigated in detail. For the study of interface resistivity, n-type Si wafers with different resistivities were bonded. The resistivity of bonded Si wafers were measured and the interface resistivity was estimated by comparing with the results of model calculations. (author)

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

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

Directory of Open Access Journals (Sweden)

Brodyn, M.S.

2014-03-01

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

Digital readouts for large microwave low-temperature detector arrays

International Nuclear Information System (INIS)

Mazin, Benjamin A.; Day, Peter K.; Irwin, Kent D.; Reintsema, Carl D.; Zmuidzinas, Jonas

2006-01-01

Over the last several years many different types of low-temperature detectors (LTDs) have been developed that use a microwave resonant circuit as part of their readout. These devices include microwave kinetic inductance detectors (MKID), microwave SQUID readouts for transition edge sensors (TES), and NIS bolometers. Current readout techniques for these devices use analog frequency synthesizers and IQ mixers. While these components are available as microwave integrated circuits, one set is required for each resonator. We are exploring a new readout technique for this class of detectors based on a commercial-off-the-shelf technology called software defined radio (SDR). In this method a fast digital to analog (D/A) converter creates as many tones as desired in the available bandwidth. Our prototype system employs a 100MS/s 16-bit D/A to generate an arbitrary number of tones in 50MHz of bandwidth. This signal is then mixed up to the desired detector resonant frequency (∼10GHz), sent through the detector, then mixed back down to baseband. The baseband signal is then digitized with a series of fast analog to digital converters (80MS/s, 14-bit). Next, a numerical mixer in a dedicated integrated circuit or FPGA mixes the resonant frequency of a specified detector to 0Hz, and sends the complex detector output over a computer bus for processing and storage. In this paper we will report on our results in using a prototype system to readout a MKID array, including system noise performance, X-ray pulse response, and cross-talk measurements. We will also discuss how this technique can be scaled to read out many thousands of detectors

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

International Nuclear Information System (INIS)

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

2001-01-01

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

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

Status of fully integrated GaAs particle detectors

International Nuclear Information System (INIS)

Braunschweig, W.; Breibach, J.; Kubicki, Th.; Luebelsmeyer, K.; Maesing, Th.; Rente, C.; Roeper, Ch.; Siemes, A.

1999-01-01

GaAs strip detectors are of interest because of their radiation hardness at room temperature and the high absorption coefficient of GaAs for x-rays. The detectors currently under development will be used in the VLQ-experiment at the H1 experiment at the HERA collider. This will be the first high energy physics experiment where GaAs detectors will be used. The detectors have a sensitive area of 5 x 4 cm with a pitch of 62 μ m. Due to the high density of channels the biasing resistors and coupling capacitors are integrated. For the resistors a resistive layer made of Cermet is used. The properties of the first fully integrated strip detector are presented

Direct observation and measurements of neutron induced deep levels responsible for N{sub eff} changes in high resistivity silicon detectors using TCT

Energy Technology Data Exchange (ETDEWEB)

Li, Z.; Li, C.J. [Brookhaven National Lab., Upton, NY (United States); Eremin, V.; Verbitskaya, E. [AN SSSR, Leningrad (Russian Federation). Fiziko-Tekhnicheskij Inst.

1996-03-01

Neutron induced deep levels responsible for changes of space charge concentration {ital N{sub eff}} in high resistivity silicon detectors have been observed directly using the transient current technique (TCT). It has been observed by TCT that the absolute value and sign of {ital N{sub eff}} experience changes due to the trapping of non- equilibrium free carriers generated near the surface (about 5 micrometers depth into the silicon) by short wavelength laser pulses in fully depleted detectors. Electron trapping causes {ital N{sub eff}} to change toward negative direction (or more acceptor-like space charges) and hole trapping causes {ital N{sub eff}} to change toward positive direction (or more donor-like space charges). The specific temperature associated with these {ital N{sub eff}} changes are those of the frozen-up temperatures for carrier emission of the corresponding deep levels. The carrier capture cross sections of various deep levels have been measured directly using different free carrier injection schemes. 10 refs., 12 figs., 3 tabs.

Performance, operation and detector studies with the ATLAS Resistive Plate Chambers

International Nuclear Information System (INIS)

Aielli, G; Bindi, M; Polini, A

2013-01-01

Resistive Plate Chambers provide the barrel region of the ATLAS detector with an independent muon trigger and a two-coordinate measurement. The chambers, arranged in three concentric double layers, are operated in a strong magnetic toroidal field and cover a surface area of about 4000 m 2 . During 2011 the LHC has provided proton-proton collisions at 7 TeV in the center-of-mass frame with a steady increase in instantaneous luminosity, summing up to about 5 fb −1 . The operational experience for this running period is presented along with studies of the detector performance as a function of luminosity, environmental conditions and working point settings. Non-event based information including in particular the large number of gas gap currents, individually monitored with nA accuracy, have been used to study the detector behavior with growing luminosity and beam currents. These data are shown to provide, when calibrated, an independent luminosity measurement and a crucial handle for understanding the ATLAS backgrounds well beyond the scope of muon triggering and detection. The measurements presented here allow to plan a strategy for the data taking in the next years and make some predictions about the detector performance at higher luminosities. They also improve the knowledge on RPC detector physics.

Creep resistant high temperature martensitic steel

Energy Technology Data Exchange (ETDEWEB)

Hawk, Jeffrey A.; Jablonski, Paul D.; Cowen, Christopher J.

2017-01-31

The disclosure provides a creep resistant alloy having an overall composition comprised of iron, chromium, molybdenum, carbon, manganese, silicon, nickel, vanadium, niobium, nitrogen, tungsten, cobalt, tantalum, boron, copper, and potentially additional elements. In an embodiment, the creep resistant alloy has a molybdenum equivalent Mo(eq) from 1.475 to 1.700 wt. % and a quantity (C+N) from 0.145 to 0.205. The overall composition ameliorates sources of microstructural instability such as coarsening of M.sub.23C.sub.6carbides and MX precipitates, and mitigates or eliminates Laves and Z-phase formation. A creep resistant martensitic steel may be fabricated by preparing a melt comprised of the overall composition followed by at least austenizing and tempering. The creep resistant alloy exhibits improved high-temperature creep strength in the temperature environment of around 650.degree. C.

Creep resistant high temperature martensitic steel

Science.gov (United States)

Hawk, Jeffrey A.; Jablonski, Paul D.; Cowen, Christopher J.

2015-11-13

The disclosure provides a creep resistant alloy having an overall composition comprised of iron, chromium, molybdenum, carbon, manganese, silicon, nickel, vanadium, niobium, nitrogen, tungsten, cobalt, tantalum, boron, and potentially additional elements. In an embodiment, the creep resistant alloy has a molybdenum equivalent Mo(eq) from 1.475 to 1.700 wt. % and a quantity (C+N) from 0.145 to 0.205. The overall composition ameliorates sources of microstructural instability such as coarsening of M.sub.23C.sub.6 carbides and MX precipitates, and mitigates or eliminates Laves and Z-phase formation. A creep resistant martensitic steel may be fabricated by preparing a melt comprised of the overall composition followed by at least austenizing and tempering. The creep resistant alloy exhibits improved high-temperature creep strength in the temperature environment of around 650.degree. C.

Development of decay energy spectroscopy using low temperature detectors.

Science.gov (United States)

Jang, Y S; Kim, G B; Kim, K J; Kim, M S; Lee, H J; Lee, J S; Lee, K B; Lee, M K; Lee, S J; Ri, H C; Yoon, W S; Yuryev, Y N; Kim, Y H

2012-09-01

We have developed a high-resolution detection technique for measuring the energy and activity of alpha decay events using low-temperature detectors. A small amount of source material containing alpha-emitting radionuclides was enclosed in a 4π metal absorber. The energy of the alpha particles as well as that of the recoiled nuclides, low-energy electrons, and low-energy x-rays and γ-rays was converted into thermal energy of the gold absorber. A metallic magnetic calorimeter serving as a fast and sensitive thermometer was thermally attached to the metal absorber. In the present report, experimental demonstrations of Q spectroscopy were made with a new meander-type magnetic calorimeter. The thermal connection between the temperature sensor and the absorber was established with annealed gold wires. Each alpha decay event in the absorber resulted in a temperature increase of the absorber and the temperature sensor. Using the spectrum measured for a drop of (226)Ra solution in a 4π gold absorber, all of the alpha emitters in the sample were identified with a demonstration of good detector linearity. The resolution of the (226)Ra spectrum showed a 3.3 keV FWHM at its Q value together with an expected gamma escape peak at the energy shifted by its γ-ray energy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Stable room-temperature thallium bromide semiconductor radiation detectors

Science.gov (United States)

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

2017-10-01

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

Stable room-temperature thallium bromide semiconductor radiation detectors

Directory of Open Access Journals (Sweden)

A. Datta

2017-10-01

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

Temperature dependence of contact resistance at metal/MWNT interface

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang-Eui; Moon, Kyoung-Seok; Sohn, Yoonchul, E-mail: yoonchul.son@samsung.com [Materials Research Center, Samsung Advanced Institute of Technology, Samsung Electronics, Suwon 443-803 (Korea, Republic of)

2016-07-11

Although contact resistance of carbon nanotube (CNT) is one of the most important factors for practical application of electronic devices, a study regarding temperature dependence on contact resistance of CNTs with metal electrodes has not been found. Here, we report an investigation of contact resistance at multiwalled nanotube (MWNT)/Ag interface as a function of temperature, using MWNT/polydimethylsiloxane (PDMS) composite. Electrical resistance of MWNT/PDMS composite revealed negative temperature coefficient (NTC). Excluding the contact resistance with Ag electrode, the NTC effect became less pronounced, showing lower intrinsic resistivity with the activation energy of 0.019 eV. Activation energy of the contact resistance of MWNT/Ag interface was determined to be 0.04 eV, two times larger than that of MWNT-MWNT network. The increase in the thermal fluctuation assisted electron tunneling is attributed to conductivity enhancement at both MWNT/MWNT and MWNT/Ag interfaces with increasing temperature.

Rise time of voltage pulses in NbN superconducting single photon detectors

Energy Technology Data Exchange (ETDEWEB)

Smirnov, K. V. [Moscow State Pedagogical University, 1 Malaya Pirogovskaya St., 119435 Moscow (Russian Federation); CJSC “Superconducting Nanotechnology” (Scontel), 5/22-1 Rossolimo St., 119021 Moscow (Russian Federation); National Research University Higher School of Economics, Moscow Institute of Electronics and Mathematics, 34 Tallinskaya St., 109028 Moscow (Russian Federation); Divochiy, A. V.; Karpova, U. V.; Morozov, P. V. [CJSC “Superconducting Nanotechnology” (Scontel), 5/22-1 Rossolimo St., 119021 Moscow (Russian Federation); Vakhtomin, Yu. B.; Seleznev, V. A. [Moscow State Pedagogical University, 1 Malaya Pirogovskaya St., 119435 Moscow (Russian Federation); CJSC “Superconducting Nanotechnology” (Scontel), 5/22-1 Rossolimo St., 119021 Moscow (Russian Federation); Sidorova, M. V. [Moscow State Pedagogical University, 1 Malaya Pirogovskaya St., 119435 Moscow (Russian Federation); Zotova, A. N.; Vodolazov, D. Yu. [Institute for Physics of Microstructure, Russian Academy of Sciences, GSP-105, 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Avenue, 603950 Nizhny Novgorod (Russian Federation)

2016-08-01

We have found experimentally that the rise time of voltage pulse in NbN superconducting single photon detectors increases nonlinearly with increasing the length of the detector L. The effect is connected with dependence of resistance of the detector R{sub n}, which appears after photon absorption, on its kinetic inductance L{sub k} and, hence, on the length of the detector. This conclusion is confirmed by our calculations in the framework of two temperature model.

Graphite-based detectors of alkali metals for nuclear power plants

International Nuclear Information System (INIS)

Kalandarishvili, A.G.; Kuchukhidze, V.A.; Sordiya, T.D.; Shartava, Sh.Sh.; Stepennov, B.S.

1993-01-01

The coolants most commonly used in today's fast reactors are alkali metals or their alloys. A major problem in nuclear plant design is leakproofing of the liquid-metal cooling system, and many leak detection methods and safety specifications have been developed as a result. Whatever the safety standards adopted for nuclear plants in different countries, they all rely on the basic fact that control of the contamination and radiation hazards involved requires reliable monitoring equipment. Results are presented of trials with some leak detectors for the alkali-metal circuits of nuclear reactors. The principal component affecting the detector performance is the sensing element. In the detectors graphite was employed, whose laminar structure enables it to absorb efficiently alkali-metal vapors at high temperatures (320--500 K). This produces a continuous series of alkali-metal-graphite solid solutions with distinct electrical, thermal, and other physical properties. The principle of operation of the detectors resides in the characteristic reactions of the metal-graphite system. One detector type uses the change of electrical conductivity of the graphite-film sensor when it is exposed to alkali-metal vapor. In order to minimize the effect of temperature on the resistance the authors prepared composite layers of graphite intercalated with a donor impurity (cesium or barium), and a graphite-nickel material. The addition of a small percentage of cesium, barium, or nickel produces a material whose temperature coefficient of resistance is nearly zero. Used as a sensing element, such a material can eliminate the need for thermostatic control of the detector

The Resistive-Plate WELL with Argon mixtures - a robust gaseous radiation detector

CERN Document Server

Moleri, Luca; Arazi, Lior; Rocha Azevedo, Carlos Davide; Oliveri, Eraldo; Pitt, Michael; Schaarschmidt, Jana; Shaked-Renous, Dan; Marques Ferreira dos Santos, Joaquim; Veloso, Joao Filipe Calapez de Albuquerque; Breskin, Amos; Bressler, Shikma

2017-01-01

A thin single-element THGEM-based, Resistive-Plate WELL (RPWELL) detector was operated with 150 GeV/c muon and pion beams in Ne/(5%CH$_4$), Ar/(5%CH$_4$) and Ar/(7%CO$_2$); signals were recorded with 1 cm$^2$ square pads and SRS/APV25 electronics. Detection efficiency values greater than 98% were reached in all the gas mixtures, at average pad multiplicity of 1.2. The use of the 10$^9${\\Omega}cm resistive plate resulted in a completely discharge-free operation also in intense pion beams. The efficiency remained essentially constant at 98-99% up to fluxes of $\\sim$10$^4$Hz/cm$^2$, dropping by a few % when approaching 10$^5$ Hz/cm$^2$. These results pave the way towards cost-effective, robust, efficient, large-scale detectors for a variety of applications in future particle, astro-particle and applied fields. A potential target application is digital hadron calorimetry.

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...

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

Science.gov (United States)

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

2018-05-01

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

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

Science.gov (United States)

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

2018-03-01

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

CDZNTE ROOM-TEMPERATURE SEMICONDUCTOR GAMMA-RAY DETECTOR FOR NATIONAL-SECURITY APPLICATIONS.

Energy Technology Data Exchange (ETDEWEB)

CAMARDA,G.S.; BOLOTNIKOV, A.E.; CUI, Y.; HOSSAIN, A.; KOHMAN, K.T.; JAMES, R.B.

2007-05-04

One important mission of the Department of Energy's National Nuclear Security Administration is to develop reliable gamma-ray detectors to meet the widespread needs of users for effective techniques to detect and identify special nuclear- and radioactive-materials. Accordingly, the Nonproliferation and National Security Department at Brookhaven National Laboratory was tasked to evaluate existing technology and to develop improved room-temperature detectors based on semiconductors, such as CdZnTe (CZT). Our research covers two important areas: Improving the quality of CZT material, and exploring new CZT-based gamma-ray detectors. In this paper, we report on our recent findings from the material characterization and tests of actual CZT devices fabricated in our laboratory and from materials/detectors supplied by different commercial vendors. In particular, we emphasize the critical role of secondary phases in the current CZT material and issues in fabricating the CZT detectors, both of which affect their performance.

Direct-reading dial for noise temperature and noise resistance

DEFF Research Database (Denmark)

Diamond, J.M.

1967-01-01

An attenuator arrangement for a noise generator is described. The scheme permits direct reading of both noise resistance and noise temperature¿the latter with a choice of source resistance.......An attenuator arrangement for a noise generator is described. The scheme permits direct reading of both noise resistance and noise temperature¿the latter with a choice of source resistance....

High temperature resistant cermet and ceramic compositions. [for thermal resistant insulators and refractory coatings

Science.gov (United States)

Phillips, W. M. (Inventor)

1978-01-01

High temperature oxidation resistance, high hardness and high abrasion and wear resistance are properties of cermet compositions particularly to provide high temperature resistant refractory coatings on metal substrates, for use as electrical insulation seals for thermionic converters. The compositions comprise a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride are also described.

High-temperature performance of gallium-nitride-based pin alpha-particle detectors grown on sapphire substrates

Science.gov (United States)

Zhu, Zhifu; Zhang, Heqiu; Liang, Hongwei; Tang, Bin; Peng, Xincun; Liu, Jianxun; Yang, Chao; Xia, Xiaochuan; Tao, Pengcheng; Shen, Rensheng; Zou, Jijun; Du, Guotong

2018-06-01

The temperature-dependent radiation-detection performance of an alpha-particle detector that was based on a gallium-nitride (GaN)-based pin structure was studied from 290 K to 450 K. Current-voltage-temperature measurements (I-V-T) of the reverse bias show the exponential dependence of leakage currents on the voltage and temperature. The current transport mechanism of the GaN-based pin diode from the reverse bias I-V fitting was analyzed. The temperature-dependent pulse-height spectra of the detectors were studied using an 241 Am alpha-particle source at a reverse bias of 10 V, and the peak positions shifted from 534 keV at 290 K to 490 keV at 450 K. The variation of full width at half maximum (FWHM) from 282 keV at 290 K to 292 keV at 450 K is almost negligible. The GaN-based pin detectors are highly promising for high-temperature environments up to 450 K.

Development of a platinum resistance thermometer on the silicon substrate for phase change studies

International Nuclear Information System (INIS)

Cai, Qingjun; Chen, Ya-Chi; Tsai, Chialun; DeNatale, Jeffrey F

2012-01-01

Resistance temperature detectors are commonly used measurement sensors in heat transfer studies. In many resistance temperature detectors, the platinum resistance thermometer (PRT) is chemically stable, has a wide temperature measurement range and possesses high measurement accuracy. In phase change studies of carbon nanotubes, bi-porous structures for microelectronic thermal management, 100 nm thick PRTs are developed on silicon substrates with 10 nm titanium adhesive to achieve precise and interface-free temperature measurements. After an annealing at 375 °C, the PRT samples are calibrated at a temperature range from 20 to 180 °C. Measurement hysteresis of temperature appears in thermal cycles. Electrical resistance tends to become low during all heating periods, which establishes the maximum measurement deviation of 10 °C. Experimental results from two different thin-film PRTs indicate that accurate and repeatable temperature measurements can be achieved by either reducing heating speed or using data in the cooling period. (paper)

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 study for resistive plate chambers of the CMS muon trigger detector

CERN Document Server

Abbrescia, M; Iaselli, G; Loddo, F; Maggi, M; Marangelli, B; Natali, S; Nuzzo, S; Pugliese, G; Ranieri, A; Romano, F; Altieri, S; Belli, G; Bruno, G; Guida, R; Ratti, S P; Riccardi, C; Torre, P; Vitulo, P

2003-01-01

A long-term aging test of a Resistive Plate Chamber (RPC) was carried out with an intense gamma **1**3**7Cs source. The detector was operated in avalanche mode and had the bakelite surface treated with linseed oil. After the irradiation the estimated dose, charge and fluence were approximately equal to the expected values after 10 years of operation in the CMS barrel region. During and after the irradiation, the RPC performance was monitored with cosmic muons and showed no relevant aging effects. Moreover, no variation of the bakelite resistance was observed.

Aging study for resistive plate chambers of the CMS muon trigger detector

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

2003-12-01

A long-term aging test of a Resistive Plate Chamber (RPC) was carried out with an intense gamma {sup 137}Cs source. The detector was operated in avalanche mode and had the bakelite surface treated with linseed oil. After the irradiation the estimated dose, charge and fluence were approximately equal to the expected values after 10 years of operation in the CMS barrel region. During and after the irradiation, the RPC performance was monitored with cosmic muons and showed no relevant aging effects. Moreover, no variation of the bakelite resistance was observed.

High temperature oxidation resistant cermet compositions

Science.gov (United States)

Phillips, W. M. (Inventor)

1976-01-01

Cermet compositions are designed to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates. A ceramic mixture of chromium oxide and aluminum oxide form a coating of chromium oxide as an oxidation barrier around the metal particles, to provide oxidation resistance for the metal particles.

Heavy-ion test of detectors with conventional and resistive Micromegas used in TPC configuration

Energy Technology Data Exchange (ETDEWEB)

Ducret, Jean-Eric, E-mail: jean-eric.ducret@cea.f [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); Legou, Philippe [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); Lukasik, Jerzy [Institute of Nuclear Physics, IFJ-PAN, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Boudard, Alain; Combet, Michel [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); Czech, BronisLaw [Institute of Nuclear Physics, IFJ-PAN, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Durand, Robert; Gorbinet, Thomas; Le Bourlout, Pascal; Leray, Sylvie [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); Matousek, Vladislav [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 854 11 Bratislava (Slovakia); Nizery, Francois [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); PawLowski, Piotr [Institute of Nuclear Physics, IFJ-PAN, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Salsac, Marie-Delphine [Commissariat a l' Energie Atomique, IRFU, F91191 Gif sur Yvette (France); Yordanov, Orlin [Institute of Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 72, Tzanigradsko chaussee Blvd, BG-1784 Sofia (Bulgaria)

2011-02-01

We have performed tests of Micromegas detector prototypes using the heavy-ion beams from the SIS synchrotron of GSI (Darmstadt, Germany). The beams varied from {sup 12}C{sup 6+} to {sup 179}Au{sup 65+} and from 250 to 1000 MeV per nucleon. We have tested two amplification technologies, conventional and resistive Micromegas, and two construction concepts, bulk-Micromegas and micro-meshes screwed on the PCB. The obtained position resolution below 200{mu}m for 5 mm wide strips implies that the bulk resistive Micromegas technology might meet the requirements of the future R3B TPC project. We also developed a fast and very low noise front-end electronics connected directly to the Printed Circuit Board (PCB) of the detector itself. This concept has shown very good performances and robustness.

On the definition of timing parameters of a superconducting detector

International Nuclear Information System (INIS)

Vasilevich, A.F.; Fannibo, A.K.

1978-01-01

By means of experimental simulation of particle passage through the superconductor intended for radiation detection, the problem of calculation of heat propagation in the superconductor from the particle track is solved. As a superconductor detector the thin wire of NbTi alloy of 10 μm diameter and 4-5 mm length is used. The particle passage through the superconductor is simulated by an instantaneous heat source which arises in a sample at lighting by short light flash the superconductor surface. The ruby laser serves as a light source. Light pulse duration is 100 ns. Light energy is absorbed in a layer of 10 -5 cm thickness at the 10 -3 cm wire diameter. Heat propagation from superconductor surface leads to the sample resistance change. Experimental and calculation dependences of detector resistance time change are given. It has been found that detector resistance change occurs with a certain delay relative to the light pulse initiation. The duration of this delay and the signal form withim 10% remain unchanged at the variation of light flash intensity by four orders which indicates a weak dependence of temperature conductivity coefficient on temperature. The coefficient determining the superconductor heat propagation time has been calculated on the experimental data base. The calculation agrees well with the experiment at the temperature conductivity coefficient value being 0.25 cm 2 /s. The knowledge of this value allows calculation of the thermal effect caused by the charged particle passage through the NbTi base superconductor. The results of calculation of temperature increase in NbTi at critical temperature during the 5.3 MeV α particle passage through the superconductor are presented [ru

Calorimetric low-temperature detectors on semiconductor base for the energy-resolving detection of heavy ions

International Nuclear Information System (INIS)

Kienlin, A. von.

1994-01-01

In the framework of this thesis for the first time calorimetric low-temperature detectors for the energy-resolving detection of heavy ions were developed and successfully applied. Constructed were two different detector types, which work both with a semiconductor thermistor. The temperature increasement effected by a particle incidence is read out. In the first detector type the thermistor was simutaneously used as absorber. The thickness of the germanium crystals was sufficient in order to stop the studied heavy ions completely. In the second type, a composed calorimeter, a sapphire crystal, which was glued on a germanium thermistor, served as absorber for the incident heavy ions. The working point of the calorimeter lies in the temperature range (1.2-4.2 K), which is reachable with a pumped 4 He cryostat. The temperatur increasement of the calorimeter amounts after the incidence of a single α particle about 20-30 μK and that after a heavy ion incidence up to some mK. An absolute energy resolution of 400-500 keV was reached. In nine beam times the calorimeters were irradiated by heavy ions ( 20 Ne, 40 Ar, 136 Xe, 208 Pb, 209 Bi) of different energies (3.6 MeV/nucleon< E<12.5 MeV/nucleon) elastically scattered from gold foils. In the pulse height spectra of the first detector type relatively broad, complex-structurated line shapes were observed. By systematic measurements dependences of the complex line structures on operational parameters of the detector, the detector temperature, and the position of the incident particle could be detected. Together with the results of further experiments a possible interpretation of these phenomena is presented. Contrarily to the complex line structures of the pure germanium thermistor the line shapes in the pulse height spectra, which were taken up in a composite germanium/sapphire calorimeter, are narrow and Gauss-shaped

Future Perspectives for the Application of Low Temperature Detectors in Heavy Ion Physics

International Nuclear Information System (INIS)

Egelhof, P.; Kraft-Bermuth, S.

2009-01-01

Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics is given, and the next generation heavy ion facility FAIR is described with a special emphasis on the potential advantage of Low Temperature Detectors (LTDs) for applications in heavy ion physics. For prototype LTDs for the energy sensitive detection of heavy ions excellent results with respect to energy resolution down to δE/E = 1-2x10 -3 for a wide range of incident energies, and with respect to other detector properties, such as energy linearity with no indication of pulse height defects even for the heaviest ions, have been obtained. In addition, prototype detectors for hard X-rays have shown energy resolutions down to δE = 30-40eV at 60 keV. Consequently, both detector schemes have already been successfully used for first experiments. At present, the design and setup of large solid angle detector arrays is in progress. With the already achieved performance, LTDs promise a large potential for applications in atomic and nuclear heavy ion physics. A brief overview of prominent examples, including high-resolution nuclear spectroscopy, nuclear structure studies with radioactive beams, superheavy element research, as well as high-resolution atomic spectroscopy on highly charged ions and tests of QED in strong electromagnetic fields is presented.

Sources of series resistance in the Harwell solid state alpha detector

International Nuclear Information System (INIS)

Rawlings, K.J.

1985-12-01

The metal-semiconductor contacts to the Harwell solid state alpha detector have been characterized and the effect of the contact geometry has been assessed. To a reasonable approximation the latter gives rise to an emitter series resistance with an expected range of 20 +- 8 ohms. The contacts behave like parallel RC networks which become noticeably frequency dependent above ca. 100 kHz. Up to this frequency the emitter contact is likely to add 6 +- 4 ohms to the series resistance and the contribution from the base contact varies inversely with the square of the diode's diameter, being 5 +- 3 ohms for a diode with a diameter of 30 mm. (author)

Multi-Electrode Resistivity Probe for Investigation of Local Temperature Inside Metal Shell Battery Cells via Resistivity: Experiments and Evaluation of Electrical Resistance Tomography

Directory of Open Access Journals (Sweden)

Xiaobin Hong

2015-01-01

Full Text Available Direct Current (DC electrical resistivity is a material property that is sensitive to temperature changes. In this paper, the relationship between resistivity and local temperature inside steel shell battery cells (two commercial 10 Ah and 4.5 Ah lithium-ion cells is innovatively studied by Electrical Resistance Tomography (ERT. The Schlumberger configuration in ERT is applied to divide the cell body into several blocks distributed in different levels, where the apparent resistivities are measured by multi-electrode surface probes. The investigated temperature ranges from −20 to 80 °C. Experimental results have shown that the resistivities mainly depend on temperature changes in each block of the two cells used and the function of the resistivity and temperature can be fitted to the ERT-measurement results in the logistical-plot. Subsequently, the dependence of resistivity on the state of charge (SOC is investigated, and the SOC range of 70%–100% has a remarkable impact on the resistivity at low temperatures. The proposed approach under a thermal cool down regime is demonstrated to monitor the local transient temperature.

Influence of Temperature and Humidity on Bakelite Resistivity

CERN Document Server

Arnaldi, R; Barret, V; Bastid, N; Blanchard, G; Chiavassa, E; Cortese, P; Crochet, Philippe; Dellacasa, G; De Marco, N; Dupieux, P; Espagnon, B; Fargeix, J; Ferretti, A; Gallio, M; Lamoine, L; Luquin, Lionel; Manso, F; Mereu, P; Métivier, V; Musso, A; Oppedisano, C; Piccotti, A; Rahmani, A; Royer, L; Roig, O; Scalas, E; Scomparin, E; Vercellin, Ermanno

1999-01-01

Presentation made at RPC99 and submitted to Elsevier PreprintThe use of phenolic or melaminic bakelite as RPC electrodes is widespread. The electrode resistivity is an important parameter for the RPC performance. As recent studies have pointed out, the bakelite resistivity changes with temperature and is influenced by humidity. In order to gain a quantitative understanding on the influence of temperature and humidity on RPC electrodes, we assembled an apparatus to measure resistivity in well-controlled conditions. A detailed description of the experimental set-up as well as the first resistivity measurements for various laminates in different environmental conditions are presented.

Characteristics of an intrinsic germanium detector for measurement of soft x-rays from high-temperature plasmas

International Nuclear Information System (INIS)

Kumagai, Katsuaki; Matoba, Tohru; Funahashi, Akimasa; Kawakami, Tomohide

1976-09-01

An intrinsic germanium (Ge(I)) detector has been prepared for measurement of soft X-ray spectra from high-temperature tokamak plasmas. Its characteristics of photo-peak efficiency, escape-peak and Compton scattering were calibrated with standard radioisotopes and soft X-rays from the JFT-2a plasma, and compared with those of a lithium-drifted silicon (Si(Li)) detector. Features of the Ge(I) detector are as follows: (i) high detection efficiency in the high energy range, (ii) wide energy range for measurement of soft X-ray spectra, and (iii) low Compton scattering effect in measurement of continuous spectra. Its dead-layer depth is about 0.06μm, and the minimum detectable energies in the Ge(I) detector are similar to those in the Si(Li) detector. The Ge(I) detector is effective for measuring soft X-ray spectra from high-temperature tokamak plasmas. (auth.)

Performance studies of resistive Micromegas detectors for the upgrade of the ATLAS Muon Spectrometer

CERN Document Server

ATLAS Collaboration; The ATLAS collaboration

2016-01-01

Resistive Micromegas (Micro MEsh Gaseous Structure) detectors have proven along the years to be a reliable high rate capable detector techno- logy characterised by an excellent spatial resolution. The ATLAS colla- boration at LHC has chosen the resistive Micromegas technology (mainly for tracking), along with the small-strip Thin Gap Chambers (sTGC, mainly for triggering), for the high luminosity upgrade of the inner muon station in the high-rapidity region, the so called New Small Wheel (NSW) upgrade project. The NSW requires fully efficient Micromegas chambers with spatial resolution better than 100μm independent of the track inci- dence angle and the magnetic field (B < 0.3 T), with a rate capability up to ∼ 10kHz/cm2. Along with the precise tracking the Micromegas chambers should be able to provide a trigger signal, complementary to the sTGC, thus a decent timing resolution is required. Several tests have been performed on small (10×10cm2) and medium size (1×0.5m2) resistive Micromegas chambers (b...

Multielement CdZnTe detectors for high-efficiency, ambient-temperature gamma-ray spectroscopy

International Nuclear Information System (INIS)

Prettyman, T.H.; Moss, C.E.; Sweet, M.R.; Ianakiev, K.; Reedy, R.C.; Li, J.; Valentine, J.D.

1998-01-01

CdZnTe is an attractive alternative to scintillator-based technology for ambient-temperature, gamma-ray spectroscopy. Large, single-element devices up to 3500 mm 3 have been developed for gamma-ray spectroscopy and are now available commercially. Because CdZnTe is a wide band-gap semiconductor, it can operate over a wide range of ambient temperatures with minimal power consumption. Over this range, CdZnTe detectors routinely yield better overall performance for gamma-ray spectroscopy than scintillator detectors. Manufacturing issues and material electronic properties limit the maximum size of single-element CdZnTe detectors. The authors are investigating methods to combine CdZnTe detectors together to improve detection efficiency and overall performance of gamma-ray spectroscopy. The applications include the assay and identification of radioisotopes for nuclear material safeguards and nonproliferation (over the energy range 50 keV to 1 MeV), and the analysis of elemental composition for planetary science (over the energy range 1 MeV to 10 MeV). Design issues for the two energy ranges are summarized

Power monitoring in space nuclear reactors using silicon carbide radiation detectors

Science.gov (United States)

Ruddy, Frank H.; Patel, Jagdish U.; Williams, John G.

2005-01-01

Space reactor power monitors based on silicon carbide (SiC) semiconductor neutron detectors are proposed. Detection of fast leakage neutrons using SiC detectors in ex-core locations could be used to determine reactor power: Neutron fluxes, gamma-ray dose rates and ambient temperatures have been calculated as a function of distance from the reactor core, and the feasibility of power monitoring with SiC detectors has been evaluated at several ex-core locations. Arrays of SiC diodes can be configured to provide the required count rates to monitor reactor power from startup to full power Due to their resistance to temperature and the effects of neutron and gamma-ray exposure, SiC detectors can be expected to provide power monitoring information for the fill mission of a space reactor.

Stability of High Temperature Standard Platinum Resistance Thermometers at High Temperatures

Directory of Open Access Journals (Sweden)

Y. A. ABDELAZIZ

2010-05-01

Full Text Available An investigation of the stability of high temperature standard platinum resistance thermometers HTSPRTs has been carried out for two different designs thermometers (with nominal resistance 0.25 Ω and 2.5 Ω from two different suppliers. The thermometers were heated for more than 160 hours at temperatures above 960 0C using a vertical furnace with a ceramic block. A study was made of the influence of the heat treatment on the stability of the resistance at the triple point of water, and on the relative resistance W(Ga at the melting point of gallium. The thermometers showed a correlation between the drift note and the values of W(Ga. It was found also that the HTSPRT which has a sensor with strip shaped support and low nominal resistance is more stable than the HTSPRT which has a sensor in the form of a coil wound on silica cross. The 0.25 Ω thermometer has better stability @ 7x10-6 0C (at TPW after 40 hour. Factors affecting the stability and accuracy of HTSPRT also will be discussed.

Development of data logger for atmospheric pressure, temperature and relative humidity for gas-filled detector

International Nuclear Information System (INIS)

Sahu, S.; Sahu, P.K.; Bhuyan, M.R.; Biswas, S.; Mohanty, B.

2014-01-01

At IoP-NISER an initiative has been taken to build and test micro-pattern gas detector such as Gas Electron Multiplier (GEM) for several upcoming High-Energy Physics (HEP) experiment projects. Temperature (t), atmospheric pressure (p) and relative humidity (RH) monitor and recording is very important for gas filled detector development. A data logger to monitor and record the ambient parameters such as temperature, relative humidity and pressure has been developed. With this data logger continuous recording of t, p, RH and time stamp can be done with a programmable sampling interval. This data is necessary to correct the gain of a gas filled detector

Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program

International Nuclear Information System (INIS)

McGuire, L.L.

1991-01-01

The Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program serves two purposes. The first is to track temperature trends during normal plant operation in areas where suspected deviations from established environmental profiles exist. This includes the use of Resistance Temperature Detectors, Recorders, and Temperature Dots for evaluation of equipment qualified life for comparison with tested parameters and the established Environmental Design Profile. It also may be used to determine the location and duration of steam leaks for effect on equipment qualified life. The second purpose of this program is to aid HVAC design engineers in determining the source of heat outside anticipated design parameters. Resistance Temperature Detectors, Recorders, and Temperature Dots are also used for this application but the results may include design changes to eliminate the excess heat or provide qualified equipment (cable) to withstand the elevated temperature, splitting of environmental zones to capture accurate temperature parameters, or continued environmental monitoring for evaluation of equipment located in hot spots

Electrical transport and temperature coefficient of resistance in polycrystalline La0.7−xAgxCa0.3MnO3 pellets: Analysis in terms of a phase coexistence transport model and phase separation model

International Nuclear Information System (INIS)

Phong, P.T.; Nguyen, L.H.; Manh, D.H.; Phuc, N.X.; Lee, I.-J.

2013-01-01

The temperature dependent resistivity and temperature coefficient of resistance of Ag doped La 0.7−x Ag x Ca 0.3 MnO 3 polycrystalline pellets (x=0, 0.05, 0.10, 0.15, and 0.20) are investigated. Ag substitution enhances the conductivity of this system. The Curie temperature also increases from 260 to 283 K with increasing Ag content. Using phase-coexistence transport model and phase separation model, we calculated the resistivity as a function of temperature and the temperature coefficient of resistivity (TCR) behavior. Comparing the calculated maximum TCR, we found that it is related to activation energy, transition temperature, and disorder in doped manganites. The relationship between the proposed TCR behavior and the transport parameters can suggest conditions improving TCR max of doped manganites for the use of the bolometric infrared detectors

Fully integrated CMOS pixel detector for high energy particles

International Nuclear Information System (INIS)

Vanstraelen, G.; Debusschere, I.; Claeys, C.; Declerck, G.

1989-01-01

A novel type of position and energy sensitive, monolithic pixel array with integrated readout electronics is proposed. Special features of the design are a reduction of the number of output channels and of the amount of output data, and the use of transistors on the high resistivity silicon. The number of output channels for the detector array is reduced by handling in parallel a number of pixels, chosen as a function of the time resolution required for the system, and by the use of an address decoder. A further reduction of data is achieved by reading out only those pixels which have been activated. The pixel detector circuit will be realized in a 3 μm p-well CMOS process, which is optimized for the full integration of readout electronics and detector diodes on high resistivity Si. A retrograde well is formed by means of a high energy implantation, followed by the appropriate temperature steps. The optimization of the well shape takes into account the high substrate bias applied during the detector operation. The design is largely based on the use of MOS transistors on the high resistivity silicon itself. These have proven to perform as well as transistors on standard doped substrate. The basic building elements as well as the design strategy of the integrated pixel detector are presented in detail. (orig.)

Temperature dependence of the radiation induced change of depletion voltage in silicon PIN detectors

International Nuclear Information System (INIS)

Ziock, H.J.; Holzscheiter, K.; Morgan, A.; Palounek, A.P.T.; Ellison, J.; Heinson, A.P.; Mason, M.; Wimpenny, S.J.; Barberis, E.; Cartiglia, N.; Grillo, A.; O'Shaughnessy, K.; Rahn, J.; Rinaldi, P.; Rowe, W.A.; Sadrozinski, H.F.W.; Seiden, A.; Spencer, E.; Webster, A.; Wichmann, R.; Wilder, M.; Coupal, D.; Pal, T.

1993-01-01

The silicon microstrip detectors that will be used in the SDC experiment at the Superconducting Super Collider (SSC) will be exposed to very large fluences of charged particles, neutrons, and gammas. The authors present a study of how temperature affects the change in the depletion voltage of silicon PIN detectors damaged by radiation. They study the initial radiation damage and the short-term and long-term annealing of that damage as a function of temperature in the range from -10 degrees C to +50 degrees C, and as a function of 800 MeV proton fluence up to 1.5 x 10 14 p/cm 2 . They express the pronounced temperature dependencies in a simple model in terms of two annealing time constants which depend exponentially on the temperature

Functional test of a Radon sensor based on a high-resistivity-silicon BJT detector

Energy Technology Data Exchange (ETDEWEB)

Dalla Betta, G.F., E-mail: dallabe@disi.unitn.it [DISI, Università di Trento, and INFN Trento, Trento (Italy); RSens srl, Modena (Italy); Tyzhnevyi, V. [DISI, Università di Trento, and INFN Trento, Trento (Italy); Bosi, A.; Bonaiuti, M. [RSens srl, Modena (Italy); Angelini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Forti, F.; Giorgi, M.A.; Morsani, F.; Paoloni, E.; Rizzo, G.; Walsh, J. [Dipartimento di Fisica, Università di Pisa, and INFN Pisa, Pisa (Italy); Lusiani, A. [Scuola Normale Superiore and INFN Pisa, Pisa (Italy); Ciolini, R.; Curzio, G.; D' Errico, F.; Del Gratta, A. [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Università di Pisa, Pisa (Italy); Bidinelli, L. [En and tech, Università di Modena e Reggio Emilia, Reggio Emilia (Italy); RSens srl, Modena (Italy); and others

2013-08-01

A battery-powered, wireless Radon sensor has been designed and realized using a BJT, fabricated on a high-resistivity-silicon substrate, as a radiation detector. Radon daughters are electrostatically collected on the detector surface. Thanks to the BJT internal amplification, real-time α particle detection is possible using simple readout electronics, which records the particle arrival time and charge. Functional tests at known Radon concentrations, demonstrated a sensitivity up to 4.9 cph/(100 Bq/m{sup 3}) and a count rate of 0.05 cph at nominally-zero Radon concentration.

A gas microstrip detector for X-ray imaging with readout of the anode by resistive division

CERN Document Server

Bateman, J E; Lodge, A B; Stephenson, R; Mutikainen, R; Suni, I; Morse, J

2002-01-01

The results are presented of a development programme aimed at the validation of the key concepts and technologies for the construction of a two-dimensional X-ray detector based on gas microstrip detector technology using resistive division along the anode to achieve the second dimension. A prototype detector and its associated electronic readout system have been developed which demonstrate the capability of a spatial resolution (standard deviation) of approximately ((1)/(1000)) of the working aperture combined with readout rates of up to 400 kHz per anode. Test results and a description of the position sensing circuitry are given.

Performance studies of resistive Micromegas detectors for the upgrade of the ATLAS Muon Spectrometer

CERN Document Server

Ntekas, Konstantinos; The ATLAS collaboration

2015-01-01

Resistive Micromegas (Micro MEsh Gaseous Structure) detectors have proven along the years to be a reliable high rate capable detector technology characterised by an excellent spatial resolution. The ATLAS collaboration at LHC has chosen the resistive Micromegas technology (mainly for tracking), along with the small-strip Thin Gap Chambers (sTGC, mainly for triggering), for the high luminosity upgrade of the inner muon station in the high-rapidity region, the so called New Small Wheel (NSW) upgrade project. The NSW requires fully efficient Micromegas chambers with spatial resolution better than $100\\,\\mu\\mathrm{m}$ independent of the track incidence angle and the magnetic field ($B<0.3\\,\\mathrm{T}$), with a rate capability up to $\\sim10\\,\\mathrm{kHz/cm^2}$. Moreover, together with the precise tracking capability the Micromegas chambers should be able to provide a trigger signal, complementary to the sTGC, thus a decent timing resolution is required. Several tests have been performed on small ($10\\times10\\,\\...

Temperature rise of the mask-resist assembly during LIGA exposure

International Nuclear Information System (INIS)

Ting, Aili

2004-01-01

Deep X-ray lithography on PMMA resist is used in the LIGA process. The resist is exposed to synchrotron X-rays through a patterned mask and then is developed in a liquid developer to make high aspect ratio microstructures. The limitations in dimensional accuracies of the LIGA generated microstructure originate from many sources, including synchrotron and X-ray physics, thermal and mechanical properties of mask and resist, and from the kinetics of the developer. This work addresses the thermal analysis and temperature rise of the mask-resist assembly during exposure in air at the Advanced Light Source (ALS) synchrotron. The concern is that dimensional errors generated at the mask and the resist due to thermal expansion will lower the accuracy of the lithography. We have developed a three-dimensional finite-element model of the mask and resist assembly that includes a mask with absorber, a resist with substrate, three metal holders, and a water-cooling block. We employed the LIGA exposure-development software LEX-D to calculate volumetric heat sources generated in the assembly by X-ray absorption and the commercial software ABAQUS to calculate heat transfer including thermal conduction inside the assembly, natural and forced convection, and thermal radiation. at assembly outer and/or inner surfaces. The calculations of assembly maximum temperature. have been compared with temperature measurements conducted at ALS. In some of these experiments, additional cooling of the assembly was produced by forced nitrogen flow ('nitrogen jets') directed at the mask surface. The temperature rise in the silicon mask and the mask holder comes directly from the X-ray absorption, but nitrogen jets carry away a significant portion of heat energy from the mask surface, while natural convection carries away negligibly small amounts energy from the holder. The temperature rise in PMMA resist is mainly from heat conducted from the silicon substrate backward to the resist and from the inner

Development of high temperature, radiation hard detectors based on diamond

Energy Technology Data Exchange (ETDEWEB)

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

2017-02-11

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

Process to produce pellet-shaped neutron activation detector elements

International Nuclear Information System (INIS)

Ambardanischvili, T.S.; Dundua, V.J.; Kiknadse, G.I.; Kolomijzev, M.A.; Zezchladse, T.V.; Gromov, V.A.; Bagdavadse, N.V.

1979-01-01

The neutron activator detector elements to measure integral neutron flux contain cobalt, zinc, phosphorous, iron, gold, indium, nickel or aluminium as detector material. Its non-aqueous nitric or acetic acid salts are solvated in an alcohol solution and mixed with an alcohol solution of phenol formaldehyde resol resin. The alcohol is destilled off under vacuum at a temperature of 60 to 90 0 C whereby the detector material in the resin matrix is homogenized. This mass is their ground, pressed to pellets and is heated to convert the resin into its unsoluble state. In order to improve the radioresistance, one can add powdered carbon to the alcohol mixture, where the carbon itself can be prepared by pyrolysis and carbonization of phenol formaldehyde resin. To improve the temperature change resistance, the pellets may be additionally heated giving rise to puyrolysis of the polycondensation resin. (DG) [de

Temperature-dependent resistance switching in SrTiO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Li, Jian-kun [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Ma, Chao; Ge, Chen, E-mail: kjjin@iphy.ac.cn, E-mail: gechen@iphy.ac.cn; Gu, Lin; He, Xu; Zhou, Wen-jia; Lu, Hui-bin [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Jin, Kui-juan, E-mail: kjjin@iphy.ac.cn, E-mail: gechen@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China); Zhang, Qing-hua [School of Materials Science and Engineering, State Key Lab of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084 (China); Yang, Guo-zhen [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China)

2016-06-13

Resistance switching phenomena were studied by varying temperature in SrTiO{sub 3} single crystal. The resistance hysteresis loops appear at a certain temperature ranging from 340 K to 520 K. With the assistance of 375 nm ultraviolet continuous laser, the sample resistance is greatly reduced, leading to a stable effect than that in dark. These resistance switching phenomena only exist in samples with enough oxygen vacancies, which is confirmed by spherical aberration-corrected scanning transmission electron microscopy measurements, demonstrating an important role played by oxygen vacancies. At temperatures above 340 K, positively charged oxygen vacancies become mobile triggered by external electric field, and the resistance switching effect emerges. Our theoretical results based on drift-diffusion model reveal that the built-in field caused by oxygen vacancies can be altered under external electric field. Therefore, two resistance states are produced under the cooperative effect of built-in field and external field. However, the increasing mobility of oxygen vacancies caused by higher temperature promotes internal electric field to reach equilibrium states quickly, and suppresses the hysteresis loops above 420 K.

Low-temperature technique for thick film resist stabilization and curing

Science.gov (United States)

Minter, Jason P.; Wong, Selmer S.; Marlowe, Trey; Ross, Matthew F.; Narcy, Mark E.; Livesay, William R.

1999-06-01

For a range of thick film photoresist applications, including MeV ion implant processing, thin film head manufacturing, and microelectromechanical systems processing, there is a need for a low-temperature method for resist stabilization and curing. Traditional methods of stabilizing or curing resist films have relied on thermal cycling, which may not be desirable due to device temperature limitations or thermally-induced distortion of the resist features.

On the temperature dependence of the excess resistivity in dilute volatile alloys

International Nuclear Information System (INIS)

Uray, L.; Vicsek, T.

1978-01-01

In recrystallized wires of many important refractory alloys, an appreciable part of the temperature dependence of the measured excess resistivity is related to the radial distribution of the volatile solutes (extrinsic temperature dependence). Both the extrinsic and the intrinsic part of the temperature dependence of the excess resistivity have been determined for dilute WFe, WCo and WRe alloys, by measuring the resistance as a function of temperature and the thickness of layers removed by electrothinning. In this way the parameters of the evaporation profiles were also determined. In the surface region at low temperatures the length scale of the inhomogeneity is comparable to the mean-free path. Therefore, the observed extrinsic temperature dependence of the excess resistivity was calculated directly from the Boltzmann equation. The WCo alloy is a Kondo system, since its resistivity shows a minimum a 20 K. (author)

Detection of electron and hole traps in CdZnTe radiation detectors by thermoelectric emission spectroscopy and thermally stimulated conductivity

International Nuclear Information System (INIS)

Lee, E.Y.; Brunett, B.A.; Olsen, R.W.; Van Scyoc, J.M. III; Hermon, H.; James, R.B.

1998-01-01

The electrical properties of CdZnTe radiation detectors are largely determined by electron and hole traps in this material. The traps, in addition to degrading the detector performance, can function as dopants and determine the resistivity of the material. Thermoelectric emission spectroscopy and thermally stimulated conductivity are used to detect these traps in a commercially available spectrometer-grade CdZnTe detector, and the electrical resistivity is measured as a function of temperature. A deep electron trap having an energy of 695 meV and cross section of 8 x 10 -16 cm 2 is detected and three hole traps having energies of 70 ± 20 meV, 105 ± 30 meV and 694 ± 162 meV are detected. A simple model based on these traps explains quantitatively all the data, including the electrical properties at room temperature and also their temperature dependence

Stability issues of high-energy resolution diode type CdTe nuclear radiation detectors in a long-term operation

CERN Document Server

Niraula, M; Aoki, T; Tomita, Y; Hatanaka, Y

2002-01-01

High-energy resolution diode type CdTe detectors were fabricated by growing an n-type epitaxial layer on high resistivity p-like crystal wafers, and their stability issues during a long-term operation were studied. Room temperature stability of the detectors was not good at low operating biases of around 200 V. However, it could be improved significantly by operating them at higher biases under full depletion conditions. On the other hand, detectors exhibited excellent stability by cooling them slightly below room temperature down to 0 deg. C. The effect of this low level of cooling on detector stability was found to be more significant than that of applying high biases at room temperature. By using the detector type presented here, stable operation could be obtained at moderate operating voltages of around 400 V and with a modest degree of cooling.

Burnout detector design for heat transfer experiments

International Nuclear Information System (INIS)

Dias, H.F.

1992-01-01

This paper describes the design of an burnout detector for heat transfer experiments, applied during tests for optimization of fuel elements for PWR reactors. The burnout detector avoids the fuel rods destruction during the experiments at the Centro de Desenvolvimento da Tecnologia Nuclear. The detector evaluates the temperature changes over the fuel rods in the temperature changes over the fuel rods in the area where the burnout phenomenon could be anticipated. As soon as the phenomenon appears, the system power supply is turned off. The thermal Circuit No. 1, during the experiments, had been composed by nine fuel rods feed parallelly by the same power supply. Fine copper wires had been attached at the centre and at the ends of the fuel rod to take two Wheat stone bridge arms. The detector had been applied across the bridge diagonals, which must be balanced the burnout excursion can be detected as a small but fast increase of the signal over the detector. Large scale experiments had been carried out to compare the resistance bridge performance against a thermocouple attached through the fuel rod wall. These experiments had been showed us the advantages of the first method over the last, because the bridge evaluates the whole fuel rod, while the thermocouple evaluates only the area where it had been attached. (author)

Measurements of Low Frequency Noise of Infrared Photo-Detectors with Transimpedance Detection System

Directory of Open Access Journals (Sweden)

Ciura Łukasz

2014-08-01

Full Text Available The paper presents the method and results of low-frequency noise measurements of modern mid-wavelength infrared photodetectors. A type-II InAs/GaSb superlattice based detector with nBn barrier architecture is compared with a high operating temperature (HOT heterojunction HgCdTe detector. All experiments were made in the range 1 Hz - 10 kHz at various temperatures by using a transimpedance detection system, which is examined in detail. The power spectral density of the nBn’s dark current noise includes Lorentzians with different time constants while the HgCdTe photodiode has more uniform 1/f - shaped spectra. For small bias, the low-frequency noise power spectra of both devices were found to scale linearly with bias voltage squared and were connected with the fluctuations of the leakage resistance. Leakage resistance noise defines the lower noise limit of a photodetector. Other dark current components give raise to the increase of low-frequency noise above this limit. For the same voltage biasing devices, the absolute noise power densities at 1 Hz in nBn are 1 to 2 orders of magnitude lower than in a MCT HgCdTe detector. In spite of this, low-frequency performance of the HgCdTe detector at ~ 230K is still better than that of InAs/GaSb superlattice nBn detector.

Temperature-induced viral resistance in Emiliania huxleyi (Prymnesiophyceae).

Science.gov (United States)

Kendrick, B Jacob; DiTullio, Giacomo R; Cyronak, Tyler J; Fulton, James M; Van Mooy, Benjamin A S; Bidle, Kay D

2014-01-01

Annual Emiliania huxleyi blooms (along with other coccolithophorid species) play important roles in the global carbon and sulfur cycles. E. huxleyi blooms are routinely terminated by large, host-specific dsDNA viruses, (Emiliania huxleyi Viruses; EhVs), making these host-virus interactions a driving force behind their potential impact on global biogeochemical cycles. Given projected increases in sea surface temperature due to climate change, it is imperative to understand the effects of temperature on E. huxleyi's susceptibility to viral infection and its production of climatically active dimethylated sulfur species (DSS). Here we demonstrate that a 3°C increase in temperature induces EhV-resistant phenotypes in three E. huxleyi strains and that successful virus infection impacts DSS pool sizes. We also examined cellular polar lipids, given their documented roles in regulating host-virus interactions in this system, and propose that alterations to membrane-bound surface receptors are responsible for the observed temperature-induced resistance. Our findings have potential implications for global biogeochemical cycles in a warming climate and for deciphering the particular mechanism(s) by which some E. huxleyi strains exhibit viral resistance.

Radiation measurements by pn junction InSb detector at the temperature from 4.2 K to 115 K

International Nuclear Information System (INIS)

Kanno, Ikuo; Yoshihara, Fumiki; Nouchi, Ryo; Sugiura, Osamu; Murase, Yasuhiro; Nakamura, Tatsuya; Katagiri, Masaki

2003-01-01

We fabricated the pn junction-type detectors on a p-type InSb substrate. Both sides of the InSb substrate were etched using a mixture of nitric and lactic acids. On the top side surface, Sn and Al were deposited by heat evaporation and then the Sn was diffused into the p-type InSb by lamp annealing and resulted in the n-type layer. Based on the confirmation of the performance of the InSb detector at temperatures of 0.5 K and 4.2 K, we concentrated on the measurement of alpha particles by the pm junction-type InSb detectors at higher operating temperatures of up to 115 K. The InSb detector showed a wide temperature operating range. We can conclude that all of the voltage was induced slowly by the holes at 4.2 K and mainly as a result of electrons at 77 K. (T. Tanaka)

A new temperature threshold detector - Application to missile monitoring

Science.gov (United States)

Coston, C. J.; Higgins, E. V.

Comprehensive thermal surveys within the case of solid propellant ballistic missile flight motors are highly desirable. For example, a problem involving motor failures due to insulator cracking at motor ignition, which took several years to solve, could have been identified immediately on the basis of a suitable thermal survey. Using conventional point measurements, such as those utilizing typical thermocouples, for such a survey on a full scale motor is not feasible because of the great number of sensors and measurements required. An alternate approach recognizes that temperatures below a threshold (which depends on the material being monitored) are acceptable, but higher temperatures exceed design margins. In this case hot spots can be located by a grid of wire-like sensors which are sensitive to temperature above the threshold anywhere along the sensor. A new type of temperature threshold detector is being developed for flight missile use. The considered device consists of KNO3 separating copper and Constantan metals. Above the KNO3 MP, galvanic action provides a voltage output of a few tenths of a volt.

Temperature Effect in Secondary Cosmic Rays (MUONS) Observed at the Ground: Analysis of the Global MUON Detector Network Data

Science.gov (United States)

de Mendonça, R. R. S.; Braga, C. R.; Echer, E.; Dal Lago, A.; Munakata, K.; Kuwabara, T.; Kozai, M.; Kato, C.; Rockenbach, M.; Schuch, N. J.; Jassar, H. K. Al; Sharma, M. M.; Tokumaru, M.; Duldig, M. L.; Humble, J. E.; Evenson, P.; Sabbah, I.

2016-10-01

The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticed that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors.

Critical Temperature tuning of Ti/TiN multilayer films suitable for low temperature detectors

OpenAIRE

Giachero, A.; Day, P.; Falferi, P.; Faverzani, M.; Ferri, E.; Giordano, C.; Marghesin, B.; Mattedi, F.; Mezzena, R.; Nizzolo, R.; Nucciotti, A.

2013-01-01

We present our current progress on the design and test of Ti/TiN Multilayer for use in Kinetic Inductance Detectors (KIDs). Sensors based on sub-stoichiometric TiN film are commonly used in several applications. However, it is difficult to control the targeted critical temperature $T_C$, to maintain precise control of the nitrogen incorporation process and to obtain a production uniformity. To avoid these problems we investigated multilayer Ti/TiN films that show a high uniformity coupled wit...

The anomalous low temperature resistivity of thermally evaporated α-Mn thin film

International Nuclear Information System (INIS)

Ampong, F.K.; Boakye, F.; Nkum, R.K.

2010-01-01

Electrical resistivity measurements have been carried out on thermally evaporated α-Mn thin film between 300 and 1.4 K using the van der Pauw four probe technique. The film was grown on a glass substrate held at a temperature of 373 K, in an ambient pressure of 5x10 -6 Torr. The results show a resistance minimum, a notable characteristic of α-Mn but at a (rather high) temperature of 194±1 K. Below the resistivity maximum which corresponds to 70 K, the resistivity drops by only 0.02 μΩm indicating a rather short range magnetic ordering. The low temperature results show a tendency towards saturation of the resistivity as the temperature approaches zero suggesting a Kondo scattering.

The anomalous low temperature resistivity of thermally evaporated alpha-Mn thin film

Energy Technology Data Exchange (ETDEWEB)

Ampong, F.K., E-mail: kampxx@yahoo.co [Department of Physics, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana); Boakye, F.; Nkum, R.K. [Department of Physics, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana)

2010-08-15

Electrical resistivity measurements have been carried out on thermally evaporated alpha-Mn thin film between 300 and 1.4 K using the van der Pauw four probe technique. The film was grown on a glass substrate held at a temperature of 373 K, in an ambient pressure of 5x10{sup -6} Torr. The results show a resistance minimum, a notable characteristic of alpha-Mn but at a (rather high) temperature of 194+-1 K. Below the resistivity maximum which corresponds to 70 K, the resistivity drops by only 0.02 muOMEGAm indicating a rather short range magnetic ordering. The low temperature results show a tendency towards saturation of the resistivity as the temperature approaches zero suggesting a Kondo scattering.

Iron-niobium-aluminum alloy having high-temperature corrosion resistance

Science.gov (United States)

Hsu, Huey S.

1988-04-14

An alloy for use in high temperature sulfur and oxygen containing environments, having aluminum for oxygen resistance, niobium for sulfur resistance and the balance iron, is discussed. 4 figs., 2 tabs.

Temperature differences within the detector of the Robertson-Berger sunburn meter, model 500, compared to global radiation

Science.gov (United States)

Kjeldstad, Berit; Grandum, Oddbjorn

1993-11-01

The Robertson-Berger sunburn meter, model 500, has no temperature compensation, and the effect of temperature on the instrument response has been investigated and discussed in several reports. It is recommended to control the temperature of the detector or at least measure it. The temperature sensor is recommended to be positioned within the detector unit. We have measured the temperature at three different positions in the detector: At the edge of the green filter where the phosphor layer is placed; at the glass tube covering the cathode; and, finally, the air temperature inside the instrument. These measurements have been performed outdoors since July 1991, with corresponding measurements of the global and direct solar radiation. There was no difference between the temperature of the glasstube covering the cathode and the air inside the instrument, at any radiation level. However, there was a difference between the green filter and the two others. The difference is linearly dependent on the amount of global radiation. The temperature difference, (Delta) T (temperature between the green filter and the air inside the sensor), increased 0.8 degree(s)C when the global irradiation increased by 100 W/m2. At maximum global radiation in Trondheim (latitude 63.4 degree(s)N) (Delta) T was approximately 5 - 6 K when the global radiation was about 700 W/m2. This was valid for temperatures between 7 degree(s)C and 30 degree(s)C. Only clear days were evaluated.

SPICE evaluation of the S/N ratio for Si microstrip detectors

International Nuclear Information System (INIS)

Candelori, A.; Paccagnella, A.; Padova Univ.; Nardi, F.

1999-01-01

SPICE simulations of AC-coupled single-sided Si microstrip detectors connected to the Pre-Shape 32 read-out chip have been performed in order to determine the geometrical characteristics which maximize the signal-to-noise ratio at room temperature. All the resistive and capacitive elements of the detector have been determined as a function of the ω/ρ ratio, by considering experimental and simulated data available in the literature. The SPICE model takes into account all the main noise source in the detector and read-out electronics. The minimum ionizing particle current signal shape characteristics have been introduced in the simulations. Two read-out configurations have been investigated for 6.4 cm and 12.8 cm long detectors. Finally, general guidelines in the detector design have been proposed starting from the simulation results

Room-temperature particle detectors with guard rings based on semi-insulating InP co-doped with Ti and Zn

International Nuclear Information System (INIS)

Yatskiv, R.; Zdansky, K.; Pekarek, L.

2009-01-01

Particle detectors made with a guard-ring (GR) electrode, operating at room temperature, have been studied. The detectors were fabricated on a semi-insulating InP crystal co-doped with Ti and Zn, grown using the Liquid-Encapsulated Czochralski technique. The detection performance of the particle detectors was evaluated using alpha particles emitted from a 241 Am source. Good detector performance has been achieved with measured charge-collection efficiencies of 99.9% and 98.2% and FWHM energy resolutions of 0.9% and 2.1%. The measurements were carried out at 230 K for negative and positive bias voltages of the irradiated electrode. The good performance is due to the SI properties of the material which has been achieved by doping with suitable Ti atoms and co-doping with a low concentration of Zn acceptors, sufficient to fully compensate shallow donors. Electron and hole charge-collection efficiencies (CCEs) were measured at various temperatures. At room temperature, unlike at low temperature (T<250 K), the hole CCE was better than the electron CCE, which can be explained by the presence of electron-trapping centres in InP with a temperature-dependent capture rate.

High-temperature and high-humidity response of the Eberline Model PRS-2 and the Eberline Model NRD neutron detector

International Nuclear Information System (INIS)

McAtee, J.L.

1981-03-01

The high-humidity and high-temperature response of the Eberline Model PRS-2 portable scaler-ratemeter and the Eberline Model NRD neutron detector was studied in an environmental chamber. The BF 3 probe used in the NRD detector was found to produce count rate surges at temperatures > 50 0 C and at relative humidity > 50%. The PRS-2 scaler-ratemeter was found to be relatively insensitive to high temperatures and high humidity

Effects of pressure and temperature on thermal contact resistance between different materials

Directory of Open Access Journals (Sweden)

Zhao Zhe

2015-01-01

Full Text Available To explore whether pressure and temperature can affect thermal contact resistance, we have proposed a new experimental approach for measurement of the thermal contact resistance. Taking the thermal contact resistance between phenolic resin and carbon-carbon composites, cuprum, and aluminum as the examples, the influence of the thermal contact resistance between specimens under pressure is tested by experiment. Two groups of experiments are performed and then an analysis on influencing factors of the thermal contact resistance is presented in this paper. The experimental results reveal that the thermal contact resistance depends not only on the thermal conductivity coefficient of materials, but on the interfacial temperature and pressure. Furthermore, the thermal contact resistance between cuprum and aluminum is more sensitive to pressure and temperature than that between phenolic resin and carbon-carbon composites.

High rate resistive plate chambers: An inexpensive, fast, large area detector of energetic charged particles for accelerator and non-accelerator applications

International Nuclear Information System (INIS)

Wuest, C.R.; Ables, E.; Bionta, R.M.; Clamp, O.; Haro, M.; Mauger, G.J.; Miller, K.; Olson, H.; Ramsey, P.

1993-05-01

Resistive Plate Chambers, or RPCs, have been used until recently as large detectors of cosmic ray muons. They are now finding use as fast large-area trigger and muon detection systems for different high energy physics detectors such the L3 Detector at LEP and future detectors to be built at the Superconducting Super Collider (SSC) and at the Large Hadron Collider (LHC) at CERN. RPC systems at these accelerators must operate with high efficiency, providing nanosecond timing resolution in particle fluences up to a few tens of kHz/cm 2 -- with thousands of square meters of active area. RPCs are simple and cheap to construct. The authors report here recent work on RPCs using new materials that exhibit a combination of desirable RPC features such as low bulk resistivity, high dielectric strength, low mass, and low cost. These new materials were originally developed for use in electronics assembly areas and other applications, where static electric charge buildup can damage sensitive electrical systems

Study and realization of a far infrared radiation detector

International Nuclear Information System (INIS)

Pereira, Daniel

1985-01-01

A F.I.R. dadiation detector (lambda = 337 μm) which makes use of the hot electron photoconductivity in InSb is described. The InSb crystal is cut in a special shape which allows high resistance (-7 KΩ) at liquid helium temperature without a magnetic field. In this way the detector can be used in the optimum point of the noise figure with a ultra-low noise pre-amplifier. A study is done to determine the sensitivity and the NEP (optical and electrical) which results respectively in 70 V/W and 10 -10 WHz sup(-1/2) for optical parameters. (Author) [pt

Pristine carbon nanotubes based resistive temperature sensor

International Nuclear Information System (INIS)

Alam, Md Bayazeed; Saini, Sudhir Kumar; Sharma, Daya Shankar; Agarwal, Pankaj B.

2016-01-01

A good sensor must be highly sensitive, faster in response, of low cost cum easily producible, and highly reliable. Incorporation of nano-dimensional particles/ wires makes conventional sensors more effective in terms of fulfilling the above requirements. For example, Carbon Nanotubes (CNTs) are promising sensing element because of its large aspect ratio, unique electronic and thermal properties. In addition to their use for widely reported chemical sensing, it has also been explored for temperature sensing. This paper presents the fabrication of CNTs based temperature sensor, prepared on silicon substrate using low cost spray coating method, which is reliable and reproducible method to prepare uniform CNTs thin films on any substrate. Besides this, simple and inexpensive method of preparation of dispersion of single walled CNTs (SWNTs) in 1,2 dichlorobenzene by using probe type ultrasonicator for debundling the CNTs for improving sensor response were used. The electrical contacts over the dispersed SWNTs were taken using silver paste electrodes. Fabricated sensors clearly show immediate change in resistance as a response to change in temperature of SWNTs. The measured sensitivity (change in resistance with temperature) of the sensor was found ∼ 0.29%/°C in the 25°C to 60°C temperature range.

Pristine carbon nanotubes based resistive temperature sensor

Energy Technology Data Exchange (ETDEWEB)

Alam, Md Bayazeed, E-mail: bayazeed786@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Jamia Millia Islamia (New Delhi, India) (India); Saini, Sudhir Kumar, E-mail: sudhirsaini1310@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Sharma, Daya Shankar, E-mail: dssharmanit15@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Maulana Azad National Institute of Technology (MANIT, Bhopal, India) (India); Agarwal, Pankaj B., E-mail: agarwalbpankj@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Academy for Scientific and Innovative Research (AcSIR, Delhi, India) (India)

2016-04-13

A good sensor must be highly sensitive, faster in response, of low cost cum easily producible, and highly reliable. Incorporation of nano-dimensional particles/ wires makes conventional sensors more effective in terms of fulfilling the above requirements. For example, Carbon Nanotubes (CNTs) are promising sensing element because of its large aspect ratio, unique electronic and thermal properties. In addition to their use for widely reported chemical sensing, it has also been explored for temperature sensing. This paper presents the fabrication of CNTs based temperature sensor, prepared on silicon substrate using low cost spray coating method, which is reliable and reproducible method to prepare uniform CNTs thin films on any substrate. Besides this, simple and inexpensive method of preparation of dispersion of single walled CNTs (SWNTs) in 1,2 dichlorobenzene by using probe type ultrasonicator for debundling the CNTs for improving sensor response were used. The electrical contacts over the dispersed SWNTs were taken using silver paste electrodes. Fabricated sensors clearly show immediate change in resistance as a response to change in temperature of SWNTs. The measured sensitivity (change in resistance with temperature) of the sensor was found ∼ 0.29%/°C in the 25°C to 60°C temperature range.

Novel low-temperature processing of low noise SDDs with on-detector electronics

International Nuclear Information System (INIS)

Sonsky, J.; Koornneef, R.; Huizenga, J.; Hollander, R.W.; Nanver, L.K.; Scholtes, T.; Roozeboom, F.; Eijk, C.W.E. van

2004-01-01

We have developed a fabrication process (SMART700 deg. process) for monolithic integration of p-channel JFETs and silicon detectors. Processing steps of the SMART700 deg. do not exceed 700 deg. C. The integrated p-JFET has a minimum gate length of 1 μm. A relatively large width can be chosen to achieve a reasonable transconductance, while the JFET capacitance still matches the small capacitance of a detector. The feedback capacitor was also realized on-chip as a double-metal capacitor. In this paper we describe DC and noise characteristics of a silicon drift detector (SDD) with a p-JFET (W/L=100/1) and a feedback capacitor integrated in the read-out anode (smart-SDD). The device has a transconductance of 1-3 mS, a top gate capacitance of ∼140 fF and a low leakage current ( 2 at room temperature). The smart-SDD with an active area of 3.8 mm 2 has reached an energy resolution of ∼50 rms electrons at a temperature of 213 K. This relatively poor energy resolution is due to generation-recombination noise caused by defects produced by a deep n-implantation. Rapid thermal annealing (RTA) and excimer laser annealing (ELA) techniques are experimented to remove the implantation damage. The noise of p-JFETs annealed with RTA and ELA is also presented

Status of the digital pixel array detector for protein crystallography

CERN Document Server

Datte, P; Beuville, E; Endres, N; Druillole, F; Luo, L; Millaud, J E; Xuong, N H

1999-01-01

A two-dimensional photon counting digital pixel array detector is being designed for static and time resolved protein crystallography. The room temperature detector will significantly enhance monochromatic and polychromatic protein crystallographic through-put data rates by more than three orders of magnitude. The detector has an almost infinite photon counting dynamic range and exhibits superior spatial resolution when compared to present crystallographic phosphor imaging plates or phosphor coupled CCD detectors. The detector is a high resistivity N-type Si with a pixel pitch of 150x150 mu m, and a thickness of 300 mu m, and is bump bonded to an application specific integrated circuit. The event driven readout of the detector is based on the column architecture and allows an independent pixel hit rate above 1 million photons/s/pixel. The device provides energy discrimination and sparse data readout which yields minimal dead-time. This type of architecture allows a continuous (frameless) data acquisition, a f...

Temperature and mixing effects on electrical resistivity of carbon fiber enhanced concrete

International Nuclear Information System (INIS)

Chang, Christiana; Song, Gangbing; Gao, Di; Mo, Y L

2013-01-01

In this paper, the effect of temperature and mixing procedure on the electrical resistivity of carbon fiber enhanced concrete is investigated. Different compositions of concrete containing varying concentrations of carbon fiber into normal and self-consolidating concrete (SCC) were tested under DC electrical loading over the temperature range −10 to 20 °C. The electrical resistivity of the bulk samples was calculated and compared against temperature. It was observed that there is an inverse exponential relationship between resistivity and temperature which follows the Arrhenius relationship. The bulk resistivity decreased with increasing fiber concentration, though data from SCC indicates a saturation limit beyond which electrical resistivity begins to drop. The activation energy of the bulk electrically conductive concrete was calculated and compared. While SCC exhibited the lowest observed electrical resistance, the activation energy was similar amongst SCC and surfactant enhanced concrete, both of which were lower than fiber dispersed in normal concrete. (paper)

High temperature creep strength of Advanced Radiation Resistant Oxide Dispersion Strengthened Steels

Energy Technology Data Exchange (ETDEWEB)

Noh, Sanghoon; Kim, Tae Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

Austenitic stainless steel may be one of the candidates because of good strength and corrosion resistance at the high temperatures, however irradiation swelling well occurred to 120dpa at high temperatures and this leads the decrease of the mechanical properties and dimensional stability. Compared to this, ferritic/martensitic steel is a good solution because of excellent thermal conductivity and good swelling resistance. Unfortunately, the available temperature range of ferritic/martensitic steel is limited up to 650 .deg. C. ODS steel is the most promising structural material because of excellent creep and irradiation resistance by uniformly distributed nano-oxide particles with a high density which is extremely stable at the high temperature in ferritic/martensitic matrix. In this study, high temperature strength of advanced radiation resistance ODS steel was investigated for the core structural material of next generation nuclear systems. ODS martensitic steel was designed to have high homogeneity, productivity and reproducibility. Mechanical alloying, hot isostactic pressing and hot rolling processes were employed to fabricate the ODS steels, and creep rupture test as well as tensile test were examined to investigate the behavior at high temperatures. ODS steels were fabricated by a mechanical alloying and hot consolidation processes. Mechanical properties at high temperatures were investigated. The creep resistance of advanced radiation resistant ODS steels was more superior than those of ferritic/ martensitic steel, austenitic stainless steel and even a conventional ODS steel.

Temperature effect on RPC performance in the ARGO-YBJ experiment

Energy Technology Data Exchange (ETDEWEB)

Aielli, G. [Dipartimento di Fisica dell' Universita ' Tor Vergata' , via della Ricerca Scientifica 1, 00133 Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy); Bacci, C. [Dipartimento di Fisica dell' Universita ' Roma Tre' , via della Vasca Navale 84, 00146 Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Roma3, via della Vasca Navale 84, 00146 Roma (Italy); Bartoli, B. [Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Complesso Universitario di Monte Sant' Angelo, via Cinthia, 80126 Napoli (Italy); Dipartimento di Fisica dell' Universita di Napoli, Complesso Universitario di Monte Sant' Angelo, via Cinthia, 80126 Napoli (Italy); Bernardini, P. [Dipartimento di Fisica dell' Universita del Salento, via per Arnesano, 73100 Lecce (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Lecce, via per Arnesano, 73100 Lecce (Italy); Bi, X.J. [Key Laboratory of Particle Astrophyics, Institute of High Energy Physics, Chinese Academy of Science, P.O. Box 918, 100049 Beijing (China); Bleve, C. [Dipartimento di Fisica dell' Universita del Salento, via per Arnesano, 73100 Lecce (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Lecce, via per Arnesano, 73100 Lecce (Italy); Branchini, P.; Budano, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma3, via della Vasca Navale 84, 00146 Roma (Italy); Bussino, S. [Dipartimento di Fisica dell' Universita ' Roma Tre' , via della Vasca Navale 84, 00146 Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Roma3, via della Vasca Navale 84, 00146 Roma (Italy); Calabrese Melcarne, A.K. [Istituto Nazionale di Fisica Nucleare - CNAF - viale Berti-Pichat 6/2, 40127 Bologna (Italy); Camarri, P. [Dipartimento di Fisica dell' Universita ' Tor Vergata' , via della Ricerca Scientifica 1, 00133 Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy)] (and others)

2009-09-11

The ARGO-YBJ experiment has been taking data for nearly 2 years. In order to monitor continuously the performance of the Resistive Plate Chamber detectors and to study the daily temperature effects on the detector performance, a cosmic ray muon telescope was setup near the carpet detector array in the ARGO-YBJ laboratory. Based on the measurements performed using this telescope, it is found that, at the actual operating voltage of 7.2 kV, the temperature effect on the RPC time resolution is about 0.04ns/deg. C and on the particle detection efficiency is about 0.03%/deg. C. Based on these figures we conclude that the environmental effects do not affect substantially the angular resolution of the ARGO-YBJ detector.

Improved spectrometric characteristics of thallium bromide nuclear radiation detectors

CERN Document Server

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

1999-01-01

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

Study on the high temperature crack resistance of tungsten

International Nuclear Information System (INIS)

Uskov, E.I.; Babak, A.V.

1983-01-01

The possibility of a multiple use of tungsten specimens in crack resistance tests in the temperature range of 600-2000 deg C is studied. It is established experimentally that the minimum length of growth of a main crack is 1x10 -4 m for the most effective repeated use of specimens. A flow diagram of mechanical tests is suggested for investigating high temperature tungsten crack resistance and estimating the degree of weakening the grain-boundary bond

THE TEMPERATURE EFFECT IN SECONDARY COSMIC RAYS (MUONS) OBSERVED AT THE GROUND: ANALYSIS OF THE GLOBAL MUON DETECTOR NETWORK DATA

Energy Technology Data Exchange (ETDEWEB)

De Mendonça, R. R. S.; Braga, C. R.; Echer, E.; Dal Lago, A.; Rockenbach, M.; Schuch, N. J. [Space Geophysics Division, National Institute for Space Research, São José dos Campos, SP, 12227-010 (Brazil); Munakata, K.; Kato, C. [Physics Department, Shinshu University, Matsumoto, Nagano, 390-8621 (Japan); Kuwabara, T. [Graduate School of Science, Chiba University, Chiba City, Chiba 263-8522 (Japan); Kozai, M. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Al Jassar, H. K.; Sharma, M. M. [Physics Department, Kuwait University, Kuwait City, 13060 (Kuwait); Tokumaru, M. [Solar Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi, 464-8601 (Japan); Duldig, M. L.; Humble, J. E. [School of Physical Sciences, University of Tasmania, Hobart, Tasmania, 7001 (Australia); Evenson, P. [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Sabbah, I. [Department of Natural Sciences, College of Health Sciences, Public Authority for Applied Education and Training, Kuwait City, 72853 (Kuwait)

2016-10-20

The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticed that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors.

THE TEMPERATURE EFFECT IN SECONDARY COSMIC RAYS (MUONS) OBSERVED AT THE GROUND: ANALYSIS OF THE GLOBAL MUON DETECTOR NETWORK DATA

International Nuclear Information System (INIS)

De Mendonça, R. R. S.; Braga, C. R.; Echer, E.; Dal Lago, A.; Rockenbach, M.; Schuch, N. J.; Munakata, K.; Kato, C.; Kuwabara, T.; Kozai, M.; Al Jassar, H. K.; Sharma, M. M.; Tokumaru, M.; Duldig, M. L.; Humble, J. E.; Evenson, P.; Sabbah, I.

2016-01-01

The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticed that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors.

Temperature dependence of the electrical resistivity of amorphous Co80-xErxB20 alloys

International Nuclear Information System (INIS)

Touraghe, O.; Khatami, M.; Menny, A.; Lassri, H.; Nouneh, K.

2008-01-01

The temperature dependence of the electrical resistivity of amorphous Co 80-x Er x B 20 alloys with x=0, 3.9, 7.5 and 8.6 prepared by melt spinning in pure argon atmosphere was studied. All amorphous alloys investigated here are found to exhibit a resistivity minimum at low temperature. The electrical resistivity exhibits logarithmic temperature dependence below the temperature of resistivity minimum T min . In addition, the resistivity shows quadratic temperature behavior in the interval T min < T<77 K. At high temperature, the electrical resistivity was discussed by the extended Ziman theory. For the whole series of alloys, the composition dependence of the temperature coefficient of electrical resistivity α shows a change in structural short range occurring in the composition range 8-9 at%

High temperature resistive phase transition in A15 high temperature superconductors

International Nuclear Information System (INIS)

Chu, C.W.; Huang, C.Y.; Schmidt, P.H.; Sugawara, K.

1976-01-01

Resistive measurements were made on A15 high temperature superconductors. Anomalies indicative of a phase transition were observed at 433 0 K in a single crystal Nb 3 Sn and at 485 0 K in an unbacked Nb 3 Ge sputtered thin film. Results are compared with the high temperature transmission electron diffraction studies of Nb 3 Ge films by Schmidt et al. A possible instability in the electron energy spectrum is discussed

Silicon drift detectors for high resolution room temperature X-ray spectroscopy

International Nuclear Information System (INIS)

Lechner, P.; Eckbauer, S.; Hauff, D.; Strueder, L.; Gatti, E.; Longoni, A.; Sampietro, M.

1996-01-01

New cylindrical silicon drift detectors have been designed, fabricated and tested. They comprise an integrated on-chip amplifier system with continuous reset, on-chip voltage divider, electron accumulation layer stabilizer, large area, homogeneous radiation entrance window and a drain for surface generated leakage current. The test of the 3.5 mm 2 large individual devices, which have also been grouped together to form a sensitive area up to 21 mm 2 have shown the following spectroscopic results: at room temperature (300 K) the devices have shown a full width at half maximum at the Mn Kα line of a radioactive 55 Fe source of 225 eV with shaping times of 250 to 500 ns. At -20 C the resolution improves to 152 eV at 2 μs Gaussian shaping. At temperatures below 200 K the energy resolution is below 140 eV. With the implementation of a digital filtering system the resolution approaches 130 eV. The system was operated with count rates up to 800 000 counts per second and per readout node, still conserving the spectroscopic qualities of the detector system. (orig.)

Low-resistivity photon-transparent window attached to photo-sensitive silicon detector

International Nuclear Information System (INIS)

Holland, S.E.

2000-01-01

The invention comprises a combination of a low resistivity, or electrically conducting, silicon layer that is transparent to long or short wavelength photons and is attached to the backside of a photon-sensitive layer of silicon, such as a silicon wafer or chip. The window is applied to photon sensitive silicon devices such as photodiodes, charge-coupled devices, active pixel sensors, low-energy x-ray sensors and other radiation detectors. The silicon window is applied to the back side of a photosensitive silicon wafer or chip so that photons can illuminate the device from the backside without interference from the circuit printed on the frontside. A voltage sufficient to fully deplete the high-resistivity photosensitive silicon volume of charge carriers is applied between the low-resistivity back window and the front, patterned, side of the device. This allows photon-induced charge created at the backside to reach the front side of the device and to be processed by any circuitry attached to the front side. Using the inventive combination, the photon sensitive silicon layer does not need to be thinned beyond standard fabrication methods in order to achieve full charge-depletion in the silicon volume. In one embodiment, the inventive backside window is applied to high resistivity silicon to allow backside illumination while maintaining charge isolation in CCD pixels

Development and Evaluation of the Muon Trigger Detector Using a Resistive Plate Chamber

International Nuclear Information System (INIS)

Park, Byeong Hyeon; Kim, Yong Kyun; Kang, Jeong Soo; Kim, Young Jin; Choi, Ihn Jea; Kim, Chong; Hong, Byung Sik

2011-01-01

The PHENIX Experiment is the largest of the four experiments that have taken data at the Relativistic Heavy Ion Collider. PHENIX, the Pioneering High Energy Nuclear Interaction eXperiment, is designed specifically to measure direct probes of the collisions such as electrons, muons, and photons. The primary goal of PHENIX is to discover and study a new state of matter called the Quark-Gluon Plasma. Among many particles, muons coming from W-boson decay gives us key information to analyze the spin of proton. Resistive plate chambers are proposed as a suitable solution as a muon trigger because of their fast response and good time resolution, flexibility in signal readout, robustness and the relatively low cost of production. The RPC detectors for upgrade were assembled and their performances were evaluated. The procedure to make the detectors better was optimized and described in detail in this thesis. The code based on ROOT was written and by using this the performance of the detectors made was evaluated, and all of the modules for north muon arm met the criteria and installation at PHENIX completed in November 2009. As RPC detectors that we made showed fast response, capacity of covering wide area with a resonable price and good spatial resolution, this will give the opportunity for applications, such as diagnosis and customs inspection system

Water resistant rhodium plated reflectors for use in the DIRC BaBar Cherenkov detector

CERN Document Server

Benkebil, M; Plaszczynski, S; Schune, M H; Wormser, G

2000-01-01

Early simulation studies showed that reflectors mounted on the photomultipliers would be useful for the DIRC BaBar Cherenkov detector, showing a gain between 20% and 30% in the number of Cherenkov photons. The proof of principle for these reflectors has been obtained during the beam test of a large-scale prototype of the DIRC detector. An extensive R and D has been conducted in order to test different metallization procedures. Indeed, the challenge was to find a metallization technique which can resist the pure de-ionized water (>15 M OMEGA) up to 10 yr. The chosen technology was rhodium plated reflectors. During the first BaBar cosmic run, the measured performance confirmed the results of the simulation, the prototype-II and the R and D.

Low-temperature photoluminescence of detector-grade HgI2

International Nuclear Information System (INIS)

Merz, J.L.; Wu, Z.L.; van den Berg, L.; Schnepple, W.F.

1981-01-01

The low-temperature photoluminescence of HgI 2 is reported. Three main luminescence bands are observed, with peaks at approx. 2.30, 2.20, and 2.00 eV at 77 K. At 4.2 K, the highest energy peak shows considerable structure. The temperature dependence of these lines indicates both free and bound exciton recombination, and very small exciton binding energies (approx. 3 to 5 MeV) have been estimated. A comparison of the results of sublimation and doping experiments suggests that the lowest energy band may be related to impurities, whereas the middle-energy band is related to I content. The two strongest bound exciton lines comprising the high-energy band show systematic correlations with the middle-energy, I-related band. Further correlations between these spectral features and the performance of nuclear radiation detectors fabricated from these samples are also noted. The temperature coefficient of the band gap is estimated from the spectral shift of luminescence lines to be approximately -1.13 x 10 -4 eV/K between 32 K and 45 K

MT3250BA: a 320×256-50µm snapshot microbolometer ROIC for high-resistance detector arrays

Science.gov (United States)

Eminoglu, Selim; Akin, Tayfun

2013-06-01

This paper reports the development of a new microbolometer readout integrated circuit (MT3250BA) designed for high-resistance detector arrays. MT3250BA is the first microbolometer readout integrated circuit (ROIC) product from Mikro-Tasarim Ltd., which is a fabless IC design house specialized in the development of monolithic CMOS imaging sensors and ROICs for hybrid photonic imaging sensors and microbolometers. MT3250BA has a format of 320 × 256 and a pixel pitch of 50 µm, developed with a system-on-chip architecture in mind, where all the timing and biasing for this ROIC are generated on-chip without requiring any external inputs. MT3250BA is a highly configurable ROIC, where many of its features can be programmed through a 3-wire serial interface allowing on-the-fly configuration of many ROIC features. MT3250BA has 2 analog video outputs and 1 analog reference output for pseudo-differential operation, and the ROIC can be programmed to operate in the 1 or 2-output modes. A unique feature of MT3250BA is that it performs snapshot readout operation; therefore, the image quality will only be limited by the thermal time constant of the detector pixels, but not by the scanning speed of the ROIC, as commonly found in the conventional microbolometer ROICs performing line-by-line (rolling-line) readout operation. The signal integration is performed at the pixel level in parallel for the whole array, and signal integration time can be programmed from 0.1 µs up to 100 ms in steps of 0.1 µs. The ROIC is designed to work with high-resistance detector arrays with pixel resistance values higher than 250 kΩ. The detector bias voltage can be programmed on-chip over a 2 V range with a resolution of 1 mV. The ROIC has a measured input referred noise of 260 µV rms at 300 K. The ROIC can be used to build a microbolometer infrared sensor with an NETD value below 100 mK using a microbolometer detector array fabrication technology with a high detector resistance value (≥ 250 K�

Radiation damage measurements in room temperature semiconductor radiation detectors

International Nuclear Information System (INIS)

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

1998-01-01

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

Design and Fabrication of the Second-Generation KID-Based Light Detectors of CALDER

Science.gov (United States)

Colantoni, I.; Cardani, L.; Casali, N.; Cruciani, A.; Bellini, F.; Castellano, M. G.; Cosmelli, C.; D'Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

2018-04-01

The goal of the cryogenic wide-area light detectors with excellent resolution project is the development of light detectors with large active area and noise energy resolution smaller than 20 eV RMS using phonon-mediated kinetic inductance detectors (KIDs). The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double readout of the light and the heat released by particles interacting in the bolometers. In this work we present the fabrication process, starting from the silicon wafer arriving to the single chip. In the first part of the project, we designed and fabricated KID detectors using aluminum. Detectors are designed by means of state-of-the-art software for electromagnetic analysis (SONNET). The Al thin films (40 nm) are evaporated on high-quality, high-resistivity (> 10 kΩ cm) Si(100) substrates using an electron beam evaporator in a HV chamber. Detectors are patterned in direct-write mode, using electron beam lithography (EBL), positive tone resist poly-methyl methacrylate and lift-off process. Finally, the chip is diced into 20 × 20 mm2 chips and assembled in a holder OFHC (oxygen-free high conductivity) copper using PTFE support. To increase the energy resolution of our detectors, we are changing the superconductor to sub-stoichiometric TiN (TiN x ) deposited by means of DC magnetron sputtering. We are optimizing its deposition by means of DC magnetron reactive sputtering. For this kind of material, the fabrication process is subtractive and consists of EBL patterning through negative tone resist AR-N 7700 and deep reactive ion etching. Critical temperature of TiN x samples was measured in a dedicated cryostat.

Comprehensive device Simulation modeling of heavily irradiated silicon detectors at cryogenic temperatures

CERN Document Server

Moscatelli, F; MacEvoy, B; Hall, G; Passeri, D; Petasecca, M; Pignatel, Giogrio Umberto

2004-01-01

Radiation hardness is a critical design concern for present and future silicon detectors in high energy physics. Tracking systems at the CERN Large Hadron Collider (LHC) are expected to operate for ten years and to receive fast hadron fluences equivalent to 10/sup 15/cm /sup -2/ 1-MeV neutrons. Recently, low temperature operating conditions have been suggested as a means of suppressing the negative effects of radiation damage on detector charge collection properties. To investigate this effect, simulations have been carried out using the ISE-TCAD DESSIS device simulator. The so-called "three-level model" has been used. A comprehensive analysis of the influence of the V/sub 2/, C/sub i/O/sub i/ and V/sub 2/O capture cross sections on the effective doping concentration (N/sub eff/) as a function of temperature and fluence has been carried out. The capture cross sections have been varied in the range 10/sup -18/-10/sup -12/ cm/sup 2/. The simulated results are compared with charge collection spectra obtained wit...

Resistive switching characteristics of interfacial phase-change memory at elevated temperature

Science.gov (United States)

Mitrofanov, Kirill V.; Saito, Yuta; Miyata, Noriyuki; Fons, Paul; Kolobov, Alexander V.; Tominaga, Junji

2018-04-01

Interfacial phase-change memory (iPCM) devices were fabricated using W and TiN for the bottom and top contacts, respectively, and the effect of operation temperature on the resistive switching was examined over the range between room temperature and 200 °C. It was found that the high-resistance (RESET) state in an iPCM device drops sharply at around 150 °C to a low-resistance (SET) state, which differs by ˜400 Ω from the SET state obtained by electric-field-induced switching. The iPCM device SET state resistance recovered during the cooling process and remained at nearly the same value for the RESET state. These resistance characteristics greatly differ from those of the conventional Ge-Sb-Te (GST) alloy phase-change memory device, underscoring the fundamentally different switching nature of iPCM devices. From the thermal stability measurements of iPCM devices, their optimal temperature operation was concluded to be less than 100 °C.

Uniformity and Stability of the CMS RPC Detector at the LHC

CERN Document Server

Costantini, S; Cimmino, A.; Garcia, G.; Lellouch, J.; Marinov, A.; Ocampo, A.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Verwilligen, P.; Yazgan, E.; Zaganidis, N.; Dimitrov, A.; Hadjiiska, R.; Litov, L.; Pavlov, B.; Petkov, P.; Aleksandrov, A.; Genchev, V.; Iaydjiev, P.; Rodozov, M.; Shopova, M.; Sultanov, G.; Ban, Y.; Cai, J.; Ge, Y.; Li, Q.; Qian, S.; Xue, Z.; Avila, C.; Chaparro, L.F.; Gomez, J.P.; Gomez Moreno, B.; Osorio Oliveros, A.F.; Sanabria, J.C.; Assran, Y.; Sharma, A.; Abbrescia, M.; Calabria, C.; Colaleo, A.; Loddo, F.; Maggi, M.; Pugliese, G.; Benussi, L.; Bianco, S.; Colafranceschi, S.; Piccolo, D.; Buontempo, S.; Carrillo, C.; Iorio, O.; Paolucci, P.; Berzano, U.; Gabusi, M.; Vitulo, P.; Kang, M.; Lee, K.S.; Park, S.K.; Shin, S.; Choi, Y.; Goh, J.; Kim, M.S.; Seo, H.

2013-01-01

The Resistive Plate Chambers (RPCs) are employed in the CMS experiment at the LHC as dedicated trigger system both in the barrel and in the endcap. This note presents results of the RPC detector uniformity and stability during the 2011 data taking period, and preliminary results obtained with 2012 data. The detector uniformity has been ensured with a dedicated High Voltage scan with LHC collisions, in order to determine the optimal operating working voltage of each individual RPC chamber installed in CMS. Emphasis is given on the procedures and results of the High Voltage calibration. Moreover, an increased detector stability has been obtained by automatically taking into account temperature and atmospheric pressure variations in the CMS cavern.

CeBr3 as a room-temperature, high-resolution gamma-ray detector

International Nuclear Information System (INIS)

Guss, Paul; Reed, Michael; Yuan Ding; Reed, Alexis; Mukhopadhyay, Sanjoy

2009-01-01

Cerium bromide (CeBr 3 ) has become a material of interest in the race for high-resolution gamma-ray spectroscopy at room temperature. This investigation quantified the potential of CeBr 3 as a room-temperature, high-resolution gamma-ray detector. The performance of CeBr 3 crystals was compared to other scintillation crystals of similar dimensions and detection environments. Comparison of self-activity of CeBr 3 to cerium-doped lanthanum tribromide (LaBr 3 :Ce) was performed. Energy resolution and relative intrinsic efficiency were measured and are presented.

Effect of some structural parameters on high-temperature crack resistance of tungsten

International Nuclear Information System (INIS)

Babak, A.V.; Uskov, E.I.

1984-01-01

The paper presents results of physicomechanical studied in high-temperature crack resistance of tungsten produced by powder metallurgy methods. It is shown that at high temperatures (>2000 deg C) a structure is formed in the material and fails at stresses independent of temperature. It is found that high-temperature tungsten crack resistance is affected neighter by changes in the effictive grain size, nor by appearance of grain-boundary microcraks in the material under high-temperature action

Shock-resistant scintillation detector

International Nuclear Information System (INIS)

Novak, W.P.

1979-01-01

A unique scintillation detector unit is disclosed which employs a special light transfer and reflector means that encases and protects the scintillator crystal against high g forces. The light transfer means comprises a flexible silicon rubber optical material bonded between the crystal and the optical window and having an axial thickness sufficient to allow the scintillator to move axially inside the container under high g forces without destroying the bonds. The reflector means comprises a soft elastic silicone rubber sleeve having a multiplicity of closely arranged tapered protrusions radiating toward and engaging the periphery of the scintillator crystal to cushion shocks effectively and having a reflective material, such as aluminum oxide powder, in the spaces between the protrusions. The reflector means provides improved shock absorption because of the uniform support and cushioning action of the protrusions and also provides the detector with high efficiency. The silicon rubber composition is specially compounded to include a large amount of aluminum oxide which enables the rubber to function effectively as a light reflector

The Use of Low Temperature Detectors for Direct Measurements of the Mass of the Electron Neutrino

Directory of Open Access Journals (Sweden)

A. Nucciotti

2016-01-01

Full Text Available Recent years have witnessed many exciting breakthroughs in neutrino physics. The detection of neutrino oscillations has proved that neutrinos are massive particles, but the assessment of their absolute mass scale is still an outstanding challenge in today particle physics and cosmology. Since low temperature detectors were first proposed for neutrino physics experiments in 1984, there has been tremendous technical progress: today this technique offers the high energy resolution and scalability required to perform competitive experiments challenging the lowest electron neutrino masses. This paper reviews the thirty-year effort aimed at realizing calorimetric measurements with sub-eV neutrino mass sensitivity using low temperature detectors.

Temperature dependence of collapse of quantized hall resistance

International Nuclear Information System (INIS)

Tanaka, Hiroyasu; Kawashima, Hironori; Iizuka, Hisamitsu; Fukuda, Hideaki; Kawaji, Shinji

2006-01-01

Similarity is observed in the deviation of Hall resistance from the quantized value with the increase in the source-drain current I SD in our butterfly-type Hall bars and in the Hall bars used by Jeanneret et al., while changes in the diagonal resistivity ρ xx with I SD are significantly different between these Hall bars. The temperature dependence of the critical Hall electric field F cr (T) for the collapse of R H (4) measured in these Hall bars is approximated using F cr (T) = F cr (0)(1 - (T/T cr ) 2 ). Here, the critical Hall electric field at zero temperature depends on the magnetic field B as F cr (0) ∝ B 3/2 . Theoretical considerations are given on F cr (T) on the basis of a temperature-dependent mobility edge model and a schema of temperature-dependent inter-Landau level tunneling probability arising from the Fermi distribution function. The former does not fit in with the I SD dependence of activation energy in ρ xx . (author)

Investigation on low room-temperature resistivity Cr/(Ba0.85Pb0.15)TiO3 positive temperature coefficient composites

DEFF Research Database (Denmark)

He, Zeming; Ma, J.; Qu, Yuanfang

2009-01-01

discussed. Using these special processes, the prepared composite with 20 wt% Cr possessed low room-temperature resistivity (2.96 Ω cm at 25 °C) and exhibited PTC effect (resistivity jump of 10), which is considered as a promising candidate for over-current protector when working at low voltage. The grain......Low room-temperature resistivity positive temperature coefficient (PTC) Cr/(Ba0.85Pb0.15)TiO3 composites were produced via a reducing sintering and a subsequent oxidation treatment. The effects of metallic content and processing conditions on materials resistivity–temperature properties were...

Influence of temperature and heat treatment on crack resistance of ceramic tungsten

International Nuclear Information System (INIS)

Uskov, E.I.; Babak, A.V.; Bega, N.D.

1983-01-01

The effect of testing temperature in the range from 20 to 2000 deg C, and recrystallization annealing at 2200 deg C on crack resistance of ceramic tungsten in vacuum, is investigated. The extension diagrams thus obtained have been treated in accordance with the standard technique. The value of the critical crack loading and the stress intensity coefficient have been determined. Structural changes have been controlled with X-ray structural methods. Crack resistance of tungsten increases in the test temperature range from 20 deg C to Tsub(x) which is connected with the increase of mobility of screw components of dislocation loops. At the temperature more than Tsub(x) the plasticity growth of ceramic tungsten takes place simultaneously with grain boundary embrittlement. Recrystallization annealing at 2200 deg C creates the structure resistant to temperature effect; crack resistance being minimum

Temperature dependence of residual electrical resistivity of Cu-Au in pseudopotential approximation

International Nuclear Information System (INIS)

Khwaja, F.A.; Ahmed, I.; Shaukat, A.

1986-08-01

The problem of temperature dependence of residual electrical resistivity of Cu-Au system is re-examined in the light of static distortion and thermal vibration of the lattice along with the short-range-order of atoms above critical temperature. The extended version of Ziman's formula for resistivity obtained yields a unified version for the calculation of resistivity in pseudopotential approximation. The temperature dependence of the quantity Δρ/ρ in this framework for Cu-Au system is found to be in better agreement with the experimental data as compared to previous calculation. (author)

Development and evaluation of the muon trigger detector using a resistive plate chamber

International Nuclear Information System (INIS)

Park, Byeong Hyeon

2010-08-01

The PHENIX Experiment is the largest of the four experiments that have taken data at the Relativistic Heavy Ion Collider. PHENIX, the Pioneering High Energy Nuclear Interaction experiment, is an exploratory experiment for the investigation of high energy collisions of heavy ions and protons. PHENIX is designed specifically to measure direct probes of the collisions such as electrons, muons, and photons. The primary goal of PHENIX is to discover and study a new state of matter called the Quark-Gluon Plasma. Among many particles, muons coming from W-boson decay gives us key information to analyze the spin of proton. Resistive plate chambers are proposed as a suitable solution as a muon trigger because of their fast response and good time resolution, flexibility in signal readout, robustness and the relatively low cost of production. The RPC detectors for upgrade were assembled and their performances were evaluated. The procedure to make the detectors better was optimized and described in detail in this thesis. The code based on ROOT was written and by using this the performance of the detectors made was evaluated, and all of the modules for north muon arm met the criteria and installation at PHENIX completed in November 2009. As RPC detectors that we made showed fast response, capacity of covering wide area with a resonable price and good spatial resolution, this will give the opportunity for applications,such as diagnosis and customs inspection system

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

A novel method for simultaneous observations of plasma ion and electron temperatures using a semiconductor-detector array

International Nuclear Information System (INIS)

Cho, T.; Numakura, T.; Kohagura, J.; Hirata, M.; Minami, R.; Watanabe, H.; Sasuga, T.; Nishizawa, Y.; Yoshida, M.; Nagashima, S.; Nakashima, Y.; Ogura, K.; Tamano, T.; Yatsu, K.; Miyoshi, S.

2002-01-01

A new method for a simultaneous observation of both plasma ion and electron temperatures is proposed using one semiconductor-detector array alone. This method will provide a new application of semiconductor-detector arrays for monitoring the key parameter set of nuclear-fusion triple product (i.e., ion temperatures, densities, and confinement time) as well as for clarifying physics mechanisms of energy transport between plasma ions and electrons under various plasma confining conditions. This method is developed on the basis of an alternative 'positive' use of a semiconductor 'dead layer'; that is, an SiO 2 layer is employed as a reliable ultra-thin energy analysis filter for low-energy charge-exchanged neutral particles from plasmas ranging in ion temperatures from 0.1 to several tens of kilo-electron-volts. Using recent fabrication techniques for the thin and uniform SiO 2 layers of the order of tens to hundreds of angstrom, our computer simulation and its experimental verification show the availability of such semiconductors for distinguishing neutral particles (for ion temperatures) from X-rays (for electron temperatures). These are simultaneously emitted from the plasmas into semiconductor detectors; however, we employ their quite different penetration lengths and the resultant different deposition depths and profiles in semiconductor materials. As a result, their output signals are distinguishable for these two different and fundamental species of plasmas

Programming Arduino to Control Bias Voltages to Temperature-Depedndent Gamma-ray Detectors aboard TRYAD Mission

Science.gov (United States)

Stevons, C. E.; Jenke, P.; Briggs, M. S.

2016-12-01

Terrestrial Gamma-ray Flashes (TGFs) are sub-millisecond gamma-ray flashes that are correlated with lightning have been observed with numerous satellites since their discovery in the early 1990s. Although substantial research has been conducted on TGFs, puzzling questions regarding their origin are still left unanswered. Consequently, the Terrestrial RaYs Analysis and Detection (TRYAD) mission is designed to solve many issues about TGFs by measuring the beam profile and orientation of TGFs in low Earth orbit. This project consists of sending two CubeSats into low-Earth orbit where they will independently sample TGF beams. Both of the TRYAD CubeSats will contain a gamma-ray detector composed of lead doped plastic scintillator coupled to silicon photomultiplier (SiPM) arrays. The gain readings of the SiPMs vary with temperature and the bias voltage must be corrected to compensate. Using an Arduino micro-controller, circuitry and software was developed to control the gain in response to the resistance of a thermistor. I will present the difficulties involved with this project along with our solutions.

Semiconductor resistance thermometer for the temperature range 300-0.3 K

International Nuclear Information System (INIS)

Zinov'eva, K.N.; Zarubin, L.I.; Nemish, I.Yu.; Vorobkalo, F.M.; Boldarev, S.T.; AN Ukrainskoj SSR, Kiev. Inst. Poluprovodnikov)

1979-01-01

Thermometric characteristics of semiconductor resistor thermometers for the temperature range from 300 to 0.3 K and from 77 to 0.3 K are given. Temperature dependence of thermometer resistances in the 300-1.3 K range was measured in cryostats with pumping-out of N 2 , H 2 and 4 He. For measurements below 1.3 K use was made of a 3 H- 4 He dissolving cryostat. The accuracy of measuring temperatures in the 1.3-0.3 K range is not below +-0.003 K, the error in determining thermometer resistances does not exceed 1%. The analysis of obtained thermometric characteristics of several series of semiconductor resistance thermometers showed that observed insignificant spread of resistances of thermometers in one series and identity of characteristics allows them to be used without preliminary calibration for relatively coarse measurements in the range from 3O0 to 0.3 K. Besides, it has been found that in the 4.2-0.3 K range the thermometric characteristics represent a straight line in the lgR-Tsup(-n) coordinates, where R is the thermometer resistance, T is the temperature and n=0.5. Thus, the thermometers of the same series can be calibrated only in 2 or 3 reference point measurements

Gamma Spectroscopy with Pixellated CdZnTe Gamma Detectors

International Nuclear Information System (INIS)

Shor, A.; Mardor, I.; Eisen, Y.

2002-01-01

Pixellated CdZnTe detectors are good candidates for room temperature gamma detection requiring spectroscopic performance with imaging capabilities. The CdZnTe materials possess high resistivity and good electron charge transport properties. The poor charge transport for the holes inherent in the CdZnTe material can be circumvented by fabricating the electrodes in any one of a number of structures designed for unipolar charge detection[1]. Recent interest in efficient gamma detection at relatively higher gamma energies has imposed more stringent demands on the CdZnTe material and on detector design and optimization. We developed at Soreq a technique where signals from all pixels and from the common electrode are processed, and then a correction is applied for improving the energy resolution and the photopeak efficiency. For illumination with an un-collimated 133 Ba source , we obtain a combined detector energy resolution of 5.0 % FWHM for the 81 keV peak, and 1.5 % FWHM for the 356 keV peak. We discuss the importance of detector material with high electron (μτ) e for thick Pixellated detectors

Probability based high temperature engineering creep and structural fire resistance

CERN Document Server

Razdolsky, Leo

2017-01-01

This volume on structural fire resistance is for aerospace, structural, and fire prevention engineers; architects, and educators. It bridges the gap between prescriptive- and performance-based methods and simplifies very complex and comprehensive computer analyses to the point that the structural fire resistance and high temperature creep deformations will have a simple, approximate analytical expression that can be used in structural analysis and design. The book emphasizes methods of the theory of engineering creep (stress-strain diagrams) and mathematical operations quite distinct from those of solid mechanics absent high-temperature creep deformations, in particular the classical theory of elasticity and structural engineering. Dr. Razdolsky’s previous books focused on methods of computing the ultimate structural design load to the different fire scenarios. The current work is devoted to the computing of the estimated ultimate resistance of the structure taking into account the effect of high temperatur...

Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

Energy Technology Data Exchange (ETDEWEB)

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

2015-06-01

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

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

International Nuclear Information System (INIS)

1981-01-01

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

Study of RPC bakelite electrodes and detector performance for INO-ICAL

International Nuclear Information System (INIS)

Kumar, A.; Gaur, A.; Hasbuddin, Md.; Kumar, P.; Kumar, P.; Kaur, D.; Mishra, S.; Naimuddin, Md.

2014-01-01

The Resistive Plate Chambers (RPCs) are going to be used as the active detectors in the India-based Neutrino Observatory (INO)-Iron Calorimeter (ICAL) experiment for the detection and study of atmospheric neutrinos. In this paper, an extensive study of structural and electrical properties for different kind of bakelite RPC electrodes is presented. RPCs fabricated from these electrodes are tested for their detector efficiency and noise rate. The study concludes with the variation of efficiency, leakage current and counting rate over the period of operation with different gas compositions and operational conditions like temperature and relative humidity

Testing of multigap Resistive Plate Chambers for Electron Ion Collider Detector Development

Science.gov (United States)

Hamilton, Hannah; Phenix Collaboration

2015-10-01

Despite decades of research on the subject, some details of the spin structure of the nucleon continues to be unknown. To improve our knowledge of the nucleon spin structure, the construction of a new collider is needed. This is one of the primary goals of the proposed Electron Ion Collider (EIC). Planned EIC spectrometers will require good particle identification. This can be provided by time of flight (TOF) detectors with excellent timing resolutions of 10 ps. A potential TOF detector that could meet this requirement is a glass multigap resistive plate chamber (mRPC). These mRPCs can provide excellent timing resolution at a low cost. The current glass mRPC prototypes have a total of twenty 0.1 mm thick gas gaps. In order to test the feasibility of this design, a cosmic test stand was assembled. This stand used the coincidence of scintillators as a trigger, and contains fast electronics. The construction, the method of testing, and the test results of the mRPCs will be presented.

X-ray response of CdZnTe detectors grown by the vertical Bridgman technique: Energy, temperature and high flux effects

Energy Technology Data Exchange (ETDEWEB)

Abbene, L., E-mail: leonardo.abbene@unipa.it [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy); Gerardi, G.; Turturici, A.A.; Raso, G. [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy); Benassi, G. [due2lab s.r.l., Via Paolo Borsellino 2, Scandiano, Reggio Emilia 42019 (Italy); Bettelli, M. [IMEM/CNR, Parco Area delle Scienze 37/A, Parma 43100 (Italy); Zambelli, N. [due2lab s.r.l., Via Paolo Borsellino 2, Scandiano, Reggio Emilia 42019 (Italy); Zappettini, A. [IMEM/CNR, Parco Area delle Scienze 37/A, Parma 43100 (Italy); Principato, F. [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy)

2016-11-01

Nowadays, CdZnTe (CZT) is one of the key materials for the development of room temperature X-ray and gamma ray detectors and great efforts have been made on both the device and the crystal growth technologies. In this work, we present the results of spectroscopic investigations on new boron oxide encapsulated vertical Bridgman (B-VB) grown CZT detectors, recently developed at IMEM-CNR Parma, Italy. Several detectors, with the same electrode layout (gold electroless contacts) and different thicknesses (1 and 2.5 mm), were realized: the cathode is a planar electrode covering the detector surface (4.1×4.1 mm{sup 2}), while the anode is a central electrode (2×2 mm{sup 2}) surrounded by a guard-ring electrode. The detectors are characterized by electron mobility-lifetime product (µ{sub e}τ{sub e}) values ranging between 0.6 and 1·10{sup −3} cm{sup 2}/V and by low leakage currents at room temperature and at high bias voltages (38 nA/cm{sup 2} at 10000 V/cm). The spectroscopic response of the detectors to monochromatic X-ray and gamma ray sources ({sup 109}Cd, {sup 241}Am and {sup 57}Co), at different temperatures and fluxes (up to 1 Mcps), was measured taking into account the mitigation of the effects of incomplete charge collection, pile-up and high flux radiation induced polarization phenomena. A custom-designed digital readout electronics, developed at DiFC of University of Palermo (Italy), able to perform a fine pulse shape and height analysis even at high fluxes, was used. At low rates (200 cps) and at room temperature (T=25 °C), the detectors exhibit an energy resolution FWHM around 4% at 59.5 keV, for comparison an energy resolution of 3% was measured with Al/CdTe/Pt detectors by using the same electronics (A250F/NF charge sensitive preamplifier, Amptek, USA; nominal ENC of 100 electrons RMS). At high rates (750 kcps), energy resolution values of 7% and 9% were measured, with throughputs of 2% and 60% respectively. No radiation polarization phenomena were

Gas filled prototype of a CdZnTe pixel detector

International Nuclear Information System (INIS)

Ramsey, B.; Sharma, D.; Sipila, H.; Gostilo, V.; Loupilov, A.

2001-01-01

CdZnTe pixel structures are currently the most promising detectors for the focal planes of hard X-ray telescopes, for astronomical observation in the range 5-100 keV. In Sharma et al. (Proc. SPIE 3765 (1999) 822) and Ramsey et al. (Nucl. Instrum. Methods A 458 (2001) 55) we presented preliminary results on the development of prototype 4x4 CdZnTe imaging detectors operated under vacuum. These pixel detectors were installed inside vacuum chambers on three-stage Peltier coolers providing detector temperatures down to -40 deg. C. A miniature sputter ion pump inside each chamber maintained the necessary vacuum of 10 -5 Torr. At a temperature of -20 deg. C we achieved an FWHM energy resolution of between 2% and 3% at 60 keV and ∼15% at 5.9 keV; however, the dependency on temperature was weak and at +20 deg. C the respective resolutions were 3% and 20%. As the detectors could be operated at room temperature without loss of their good characteristics it was possible to exclude the sputter ion pump and fill the chamber with dry nitrogen instead. We have tested a nitrogen-filled CdZnTe (5x5x1 mm 3 ) prototype having 0.65x0.65 mm 2 readout pads on a 0.75 mm pitch. The interpixel resistance at an applied voltage of 10 V was higher than 50 GΩ and the pixel leakage currents at room temperature with a bias of 200 V between each pad and the common electrode did not exceed 0.8 nA. The pixel detector inside the microassembly, which also contained the input stages of the preamplifiers, was installed on a Peltier cooler to maintain the detector temperature at +20 deg. C. To define real leakage currents of the pixels in their switched-on state we have checked the voltage on the preamplifiers feedback resistors. The resulting currents were 10-50 pA at a detector bias of 500 V. Under test, the typical energy resolution per pixel at +20 deg. C was ∼3% at energy 59.6 keV and ∼20% at energy 5.9 keV, which are similar to the values obtained in the vacuum prototype at room temperature

Calorimetric low-temperature detectors for low-energy (E≤1 MeV/amu) heavy ions and their first application in the accelerator mass spectroscopy for trace analysis of 236U

International Nuclear Information System (INIS)

Kraft-Bermuth, S.

2004-01-01

In the thesis presented here, calorimetric low temperature detectors were for the first time applied in accelerator mass spectrometry (AMS) to determine the isotope ratio of 236 U to 238 U in several samples of natural uranium. The detectors consist of a superconducting aluminium film deposited onto a sapphire absorber which is used as thermistor. An energetic heavy ion deposits its kinetic energy as heat in the absorber. The temperature rise is detected by the resistance change of the superconductor. The AMS experiments were performed at the tandem accelerator VERA of the ''Institut fuer Isotopenforschung und Kernphysik'' of the University of Vienna. In an energy range of 10-60 MeV, a relative energy resolution of ΔE/E=7.10 -3 could be achieved, one order of magnitude better than with conventional ionization detectors. Improving thermal and electronic noise yielded in a second experiment for uranium ions with E=17 MeV a relative energy resolution of ΔE/E=4.6.10 -3 . The energy response of the detectors was linear over the whole energy range and independent of the ion mass. Down to a level of 0.1%, no pulse height defect was observed. With the energy resolution obtained it is possible to determine the isotope ratio of 236 U/ 238 U for several samples of natural uranium. With the resolution achieved it is possible furthermore to apply the detectors in several test experiments for direct mass identification of heavy ions using a combined energy/time of flight measurement. In these first tests, a mass resolution of ΔM/M=(8.5-11.0).10 -3 was achieved. In a first test to apply the detectors for detection of so called ''super heavy elements (Z>=112)'', the large dynamic range allowed to identify the reaction products and their alpha decays simultaneously and time dependent. (orig.)

Development of Creep-Resistant and Oxidation-Resistant Austenitic Stainless Steels for High Temperature Applications

Science.gov (United States)

Maziasz, Philip J.

2018-01-01

Austenitic stainless steels are cost-effective materials for high-temperature applications if they have the oxidation and creep resistance to withstand prolonged exposure at such conditions. Since 1990, Oak Ridge National Laboratory (ORNL) has developed advanced austenitic stainless steels with creep resistance comparable to Ni-based superalloy 617 at 800-900°C based on specially designed "engineered microstructures" utilizing a microstructure/composition database derived from about 20 years of radiation effect data on steels. The wrought high temperature-ultrafine precipitate strengthened (HT-UPS) steels with outstanding creep resistance at 700-800°C were developed for supercritical boiler and superheater tubing for fossil power plants in the early 1990s, the cast CF8C-Plus steels were developed in 1999-2001 for land-based gas turbine casing and diesel engine exhaust manifold and turbocharger applications at 700-900°C, and, in 2015-2017, new Al-modified cast stainless steels with oxidation and creep resistance capabilities up to 950-1000°C were developed for automotive exhaust manifold and turbocharger applications. This article reviews and summarizes their development and their properties and applications.

Evaluation of the local temperature of conductive filaments in resistive switching materials

International Nuclear Information System (INIS)

Yalon, E; Cohen, S; Gavrilov, A; Ritter, D

2012-01-01

The resistive switching effect in metal oxides and other dielectric materials is among the leading future non-volatile memory technologies. Resistive switching is widely ascribed to the formation and rupture of conductive filaments in the oxide, which are generated by temperature-enhanced nano-scale ion migration or other thermal effects. In spite of the central role of the local filament temperature on the switching effect, as well as on the conduction and reliability physics, no measurement methods of the filament temperature are yet available. In this work, we report on a method for evaluating the conducting filament temperature, using a metal–insulator–semiconductor bipolar transistor structure. The filament temperature is obtained by analyzing the thermal excitation rate of electrons from the filament Fermi level into the conduction band of a p-type semiconductor electrode. Measurements were carried out to obtain the conductive filament temperature in hafnia at varying ambient temperatures in the range of 3–300 K. Significant Joule heating of the filament was observed across the entire measured ambient temperature range. The extracted temperatures provide physical insight into the resistive switching effect. (paper)

Online junction temperature measurement via internal gate resistance during turn-on

DEFF Research Database (Denmark)

Baker, Nick; Munk-Nielsen, Stig; Liserre, Marco

2014-01-01

A new method for junction temperature measurement of power semiconductor switches is presented. The measurement exploits the temperature dependent resistance of the temperature sensitive electrical parameter (TSEP): the internal gate resistance. This dependence can be observed during the normal...... switching transitions of an IGBT or MOSFET, and as a result the presented method uses the integral of the gate voltage during the turn-on delay. A measurement circuit can be integrated into a gate driver with no modification to converter or gate driver operation and holds significant advantages over other...

Lithium germanium detectors reactivation

International Nuclear Information System (INIS)

Nicolai, J.A.; Marti, G.V.; Riso, J.M.; Gimenez, C.R.

1981-01-01

A convenient method to regenerate the characteristics of damaged Ge(li) detectors, that has been applied in the authors' laboratory, is described. The procedure consists in warming-up the crystal in its cryostat to temperatures between 10 deg C and 30 deg C above room temperature, in order to clean its surface. Subsequent cooling down to liquid nitrogen temperature, followed by one or more clean-up drifting processes, are applied to the crystals. This paper summarizes the results obtained with several detectors; this method was applied successfully to 15 detectors more. (author) [es

The high temperature resistivity of Ba2YCu3O7-chi

International Nuclear Information System (INIS)

Xingkui, Z.; Shining, Z.; Hao, W.; Shiyuan, Z.; Ningshen, Z.; Ziran, X.

1988-01-01

The high temperature resistivity (rho), thermogravimetry (TG) and derivative thermogravimetric (DTG) have been used to characterize superconductor Ba 2 YCu 3 O 7-chi (BYCO) in O 2 , air and N 2 . The resistivity is linear from room temperature at 350 0 C and then deviate from linearity with oxygen evolution, the derivative of resistivity drho/dT increases abruptly near orthorhombic to tetragonal phase transition. These phenomena can give good explanations for a two-band Drude model

The High Temperature Resistivity of Ba2YCu3O7-x

Science.gov (United States)

Xingkui, Zhang; Shining, Zhu; Hao, Wang; Shiyuan, Zhang; Su, Ye; Ningshen, Zhou; Ziran, Xu

The high temperature resistivity (ρ), thermogravimetry (TG) and derivative thermogravimetry (DTG) have been used to characterize superconductor Ba2YCu3O7-x (BYCO) in O2, air and N2. The resistivity is linear from room temperature to 350°C and then deviate from linearity with oxygen evolution, the derivative of resistivity dρ/dT increases abruptly near orthorhombic to tetragonal phase transition. These phenomena can give good explanations for a two-band Drude model.

High Temperature Terahertz Detectors Realized by a GaN High Electron Mobility Transistor

Science.gov (United States)

Hou, H. W.; Liu, Z.; Teng, J. H.; Palacios, T.; Chua, S. J.

2017-04-01

In this work, a high temperature THz detector based on a GaN high electron mobility transistor (HEMT) with nano antenna structures was fabricated and demonstrated to be able to work up to 200 °C. The THz responsivity and noise equivalent power (NEP) of the device were characterized at 0.14 THz radiation over a wide temperature range from room temperature to 200 °C. A high responsivity Rv of 15.5 and 2.7 kV/W and a low NEP of 0.58 and 10 pW/Hz0.5 were obtained at room temperature and 200 °C, respectively. The advantages of the GaN HEMT over other types of field effect transistors for high temperature terahertz detection are discussed. The physical mechanisms responsible for the temperature dependence of the responsivity and NEP of the GaN HEMT are also analyzed thoroughly.

Influence of Soil Temperature on Meloidogyne incognita Resistant and Susceptible Cotton, Gossypium hirsutum

OpenAIRE

Carter, William W.

1982-01-01

The degree of resistance by a cotton plant to Meloidogyne incognita is affected by soil temperature, particularly in moderately resistant cultivars, The total number of nematodes in the resistant and moderately resistant rools at 35 C was equal to, or greater than, the number in susceptible roots at 20, 25, or 30 C. A shift in numbers to developing and egg-bearing forms of nematodes in the susceptible cultivar as tentperature increased indicates development was affected by temperature rather ...

A fully automated temperature-dependent resistance measurement setup using van der Pauw method

Science.gov (United States)

Pandey, Shivendra Kumar; Manivannan, Anbarasu

2018-03-01

The van der Pauw (VDP) method is widely used to identify the resistance of planar homogeneous samples with four contacts placed on its periphery. We have developed a fully automated thin film resistance measurement setup using the VDP method with the capability of precisely measuring a wide range of thin film resistances from few mΩ up to 10 GΩ under controlled temperatures from room-temperature up to 600 °C. The setup utilizes a robust, custom-designed switching network board (SNB) for measuring current-voltage characteristics automatically at four different source-measure configurations based on the VDP method. Moreover, SNB is connected with low noise shielded coaxial cables that reduce the effect of leakage current as well as the capacitance in the circuit thereby enhancing the accuracy of measurement. In order to enable precise and accurate resistance measurement of the sample, wide range of sourcing currents/voltages are pre-determined with the capability of auto-tuning for ˜12 orders of variation in the resistances. Furthermore, the setup has been calibrated with standard samples and also employed to investigate temperature dependent resistance (few Ω-10 GΩ) measurements for various chalcogenide based phase change thin films (Ge2Sb2Te5, Ag5In5Sb60Te30, and In3SbTe2). This setup would be highly helpful for measurement of temperature-dependent resistance of wide range of materials, i.e., metals, semiconductors, and insulators illuminating information about structural change upon temperature as reflected by change in resistances, which are useful for numerous applications.

Recent progress in infrared detector technologies

Science.gov (United States)

Rogalski, A.

2011-05-01

In the paper, fundamental and technological issues associated with the development and exploitation of the most advanced infrared detector technologies are discussed. In this class of detectors both photon and thermal detectors are considered. Special attention is directed to HgCdTe ternary alloys on silicon, type-II superlattices, uncooled thermal bolometers, and novel uncooled micromechanical cantilever detectors. Despite serious competition from alternative technologies and slower progress than expected, HgCdTe is unlikely to be seriously challenged for high-performance applications, applications requiring multispectral capability and fast response. However, the nonuniformity is a serious problem in the case of LWIR and VLWIR HgCdTe detectors. In this context, it is predicted that type-II superlattice system seems to be an alternative to HgCdTe in long wavelength spectral region. In well established uncooled imaging, microbolometer arrays are clearly the most used technology. Present state-of-the-art microbolometers are based on polycrystalline or amorphous materials, typically vanadium oxide (VO x) or amorphous silicon (α-Si), with only modest temperature sensitivity and noise properties. Basic efforts today are mainly focused on pixel reduction and performance enhancement. Attractive alternatives consist of low-resistance α-SiGe monocrystalline SiGe quantum wells or quantum dots. In spite of successful commercialization of uncooled microbolometers, the infrared community is still searching for a platform for thermal imagers that combine affordability, convenience of operation, and excellent performance. Recent advances in MEMS systems have lead to the development of uncooled IR detectors operating as micromechanical thermal detectors. Between them the most important are biomaterial microcantilevers.

Temperature relaxation and the Kapitza boundary resistance paradox

OpenAIRE

Brink, Alec Maassen van den; Dekker, H.

1994-01-01

The calculation of the Kapitza boundary resistance between dissimilar harmonic solids has since long (Little [Can. J. Phys. 37, 334 (1959)]) suffered from a paradox: this resistance erroneously tends to a finite value in the limit of identical solids. We resolve this paradox by calculating temperature differences in the final heat-transporting state, rather than with respect to the initial state of local equilibrium. For a one-dimensional model we thus derive an exact, paradox-free formula fo...

BiI{sub 3} single crystal for room-temperature gamma ray detectors

Energy Technology Data Exchange (ETDEWEB)

Saito, T., E-mail: saito.tatsuya125@canon.co.jp [Frontier Research Center, Canon Inc., 3-30-2, Shimomaruko, Ohta-ku, Tokyo 146-8501 (Japan); Iwasaki, T. [Frontier Research Center, Canon Inc., 3-30-2, Shimomaruko, Ohta-ku, Tokyo 146-8501 (Japan); Kurosawa, S.; Yoshikawa, A. [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Den, T. [Frontier Research Center, Canon Inc., 3-30-2, Shimomaruko, Ohta-ku, Tokyo 146-8501 (Japan)

2016-01-11

BiI{sub 3} single crystals were grown by the physical vapor transport method. The repeated sublimation of the starting material reduced impurities in the BiI{sub 3} single crystal to sub-ppm levels. The detector was fabricated by depositing Au electrodes on both surfaces of the 100-μm-thick BiI{sub 3} single crystal platelet. The resistivity of the BiI{sub 3} single crystal was increased by post-annealing in an iodine atmosphere (ρ=1.6×10{sup 11} Ω cm). Pulse height spectroscopy measurements showed clear peaks in the energy spectrum of alpha particles or gamma rays. It was estimated that the mobility-lifetime product was μ{sub e}τ{sub e}=3.4–8.5×10{sup −6} cm{sup 2}/V and the electron–hole pair creation energy was 5.8 eV. Our results show that BiI{sub 3} single crystals are promising candidates for detectors used in radiographic imaging or gamma ray spectroscopy.

Position detector

International Nuclear Information System (INIS)

Hayakawa, Toshifumi.

1985-01-01

Purpose: To enable to detect the position of an moving object in a control rod position detector, stably in a digital manner at a high accuracy and free from the undesired effects of circumstantial conditions such as the reactor temperature. Constitution: Coils connected in parallel with each other are disposed along the passage of a moving object and variable resistors and relays are connected in series with each of the coils respectively. Light emitting diodes is connected in series with the contacts of the respective relays. The resistance value of the variable resistors are adjusted depending on the changes in the circumstantial conditions and temperature distribution upon carrying out the positional detection. When the object is inserted into a coils, the relevant relay is deenergized, by which the relay contacts are closed to light up the diode. In the same manner, as the object is successively inserted into the coils, the diodes are lighted-up successively thereby enabling highly accurate and stable positional detection in a digital manner, free from the undesired effects of the circumstantial conditions. (Horiuchi, T.)

Resistance temperature sensor aging degradation identification using LCSR (Loop Current Step Response) test

International Nuclear Information System (INIS)

Santos, Roberto Carlos dos; Goncalves, Iraci Martine Pereira

2013-01-01

Most critical process temperatures in nuclear power plants are measured using RTD (Resistance Temperature Detector) and thermocouples. In a PWR (Pressure Water Reactor) plant, the primary coolant temperature and feedwater temperature are measured using RTDs, and the temperature of the water that exits the reactor core is measured using thermocouples. These thermocouples are mainly used for temperature monitoring purposes and are therefore not generally subject to very stringent requirements for accuracy and response-time performance. In contrast, primary coolant RTDs typically feed the plant's control and safety systems and must, therefore, be very accurate and have good dynamic performance. The response time of RTDs and thermocouples has been characterized by a single parameter called the Plunge Time Constant. This is defined as the time it takes the sensor output to achieve 63.2 percent of its final value after a step change in temperature is impressed on its surface. This step change is typically achieved by suddenly immersing the sensor in a rotating tank of water, called Plunge Test. In nuclear reactors, however, plunge testing is inconvenient because the sensor must be removed from the reactor coolant piping and taken to a laboratory for testing. Nuclear reactor service conditions of 150 bar and 300°C are difficult to reproduce in the laboratory. Therefore, all laboratory tests are performed at much milder conditions, and the results are extrapolated to service conditions. This leads to significant errors in the measurement of sensor response times and an insitu test method called LCSR - Loop Current Step Response test was developed in the mid-1970s to measure remotely the response time of RTDs. In the LCSR method, the sensing element is heated by an electric current; the current causes Joule heating in the sensor and results in a temperature transient inside the sensor. The temperature transient in the element is recorded, and from this transient, the

Etching characteristics of a CR-39 track detector at room temperature in different etching solutions

International Nuclear Information System (INIS)

Dajko, G.

1991-01-01

Investigations were carried out to discover how the etching characteristics of CR-39 detectors change with varying conditions of the etching process. Measurements were made at room temperature in pure NaOH and KOH solutions; in different alcoholic KOH solutions (PEW solution, i.e. potassium hydroxide, ethyl alcohol, water); and in NaOH and KOH solutions containing different additives. The bulk etching rate of the detector (V B ) and the V (= V T /V B ) function, i.e. track to bulk etch rates ratio, for 6.1 MeV α-particles, were measured systematically. (author)

The development of the room temperature LWIR HgCdTe detectors for free space optics communication systems

Science.gov (United States)

Martyniuk, Piotr; Gawron, Waldemar; Mikołajczyk, Janusz

2017-10-01

There are many room temperature applications to include free space optics (FSO) communication system combining quantum cascade lasers sources where HgCdTe long-wave (8-12 micrometer) infrared radiation (LWIR) detector reaching ultrafast response time 109 cmHz1/2/W. Since commercially available FSO could operate separately in SWIR, MWIR and LWIR range - the dual band detectors should be implemented into FSO. This paper shows theoretical performance of the dual band back-to-back MWIR and LWIR HgCdTe detector operating at 300 K pointing out the MWIR active layer influence on LWIR operating regime.

Temperature dependency of electrical resistivity of soils; Tsuchi no hiteiko no ondo izonsei ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Park, S; Matsui, T [Osaka University, Osaka (Japan). Faculty of Engineering; Park, M; Fujiwara, H [Osaka University, Osaka (Japan)

1997-10-22

Kinds of ground materials, porosity, electrical resistivity of pores, degree of saturation, and content of clays are the factors affecting the electrical resistivity of soils. In addition to these factors, the electrical resistivity of soils around hot spring water and geothermal areas depends on the temperature due to fluctuation of cation mobility in the pore water with the temperature. In this paper, the temperature dependency of electrical resistivity of groundwater and soils is investigated by recognizing that of groundwater as that of pore water. As a result, it was found that the electrical resistivity of groundwater becomes lower as increasing the amount of dissolved cation, and that the temperature dependency of electrical resistivity is not significant because of the small mobility of cation. The electrical resistivity of soils was significantly affected by that of pore water, in which the mobility of cation was changed with temperature changes. Accordingly, the temperature dependency of electrical resistivity of soils has a similar tendency as that of groundwater. 5 refs., 9 figs., 2 tabs.

Trends in the design of front-end systems for room temperature solid state detectors

International Nuclear Information System (INIS)

Manfredi, Pier F.; Re, Valerio

2003-01-01

The paper discusses the present trends in the design of low-noise front-end systems for room temperature semiconductor detectors. The technological advancement provided by submicron CMOS and BiCMOS processes is examined from several points of view. The noise performances are a fundamental issue in most detector applications and suitable attention is devoted to them for the purpose of judging whether or not the present processes supersede the solutions featuring a field-effect transistor as a front-end element. However, other considerations are also important in judging how well a monolithic technology suits the front-end design. Among them, the way a technology lends itself to the realization of additional functions, for instance, the charge reset in a charge-sensitive loop or the time-variant filters featuring the special weighting functions that may be requested in some applications of CdTe or CZT detectors

Ion temperature measurement of indirectly-driven implosions using a geometry-compensated neutron time-of-flight detector

International Nuclear Information System (INIS)

Murphy, T.J.; Lerche, R.A.; Bennett, C.; Howe, G.

1994-05-01

A geometry-compensated neutron time-of-flight detector has been constructed and used on Nova to measure ion temperatures from indirectly-driven implosions with yields between 2.5 and 5 x 10 9 DD neutrons. The detector, which has an estimated response time of 250 ps, was located 150 cm from the targets. Due to the long decay time of the scintillator, the time-of-flight signal must be unfolded from the measured detector signal. Several methods for determining the width of the neutron energy spectrum from the data have been developed and give similar results. Scattered x rays continue to be a problem for low yield shots, but should be brought under control with adequate shielding

Ion-temperature measurement of indirectly driven implosions using a geometry-compensated neutron time-of-flight detector

International Nuclear Information System (INIS)

Murphy, T.J.; Lerche, R.A.; Bennett, C.; Howe, G.

1995-01-01

A geometry-compensated neutron time-of-flight detector has been constructed and used on Nova to measure ion temperatures from indirectly driven implosions with yields between 2.5 and 5x10 9 DD neutrons. The detector, which has an estimated respond time of 250 ps, was located 150 cm from the targets. Due to the long decay time of the scintillator, the time-of-flight signal must be unfolded from the measured detector signal. Several methods for determining the width of the neutron energy spectrum from the data have been developed and give similar results. Scattered x rays continue to be a problem for low yield shots, but should be brought under control with adequate shielding

A Challenge to Improve High-Temperature Platinum Resistance Thermometer

Science.gov (United States)

Tanaka, Y.; Widiatmo, J. V.; Harada, K.; Kobayashi, T.; Yamazawa, K.

2017-05-01

High-temperature standard platinum resistance thermometers (HTSPRTs) are used to interpolate the international temperature scale of 1990 (ITS-90), especially for temperatures between the aluminum and the silver points. For this, long-term stability of the HTSPRT is essential. CHINO R800-3L type SPRT, which has a nominal resistance at the triple point of water (TPW) around 0.25 Ω , is the one developed earlier for the interpolation of the ITS-90 at this temperature range. Further development to this previous model has been carried out for the purpose of improving the thermal stability. The improvement was focused on reducing the effect coming from the difference in thermal expansion between platinum wire and the quartz frame on which the platinum wire is installed. New HTSPRTs were made by CHINO Corporation. Some series of tests were carried out at CHINO and at NMIJ. Initial tests after the HTSPRT fabrication were done at CHINO, where thermal cycles between 500°C and 980°C were applied to the HTSPRTs to see change in the resistances at the TPW (R_{TPW}) and at the gallium point (R_{Ga}). Repeated resistance measurements at the silver point (R_{Ag}) were performed after completing the thermal cycling test. Before and after every measurement at silver point, R_{TPW} was measured, while before and after every two silver point realization R_{Ga} were measured. After completing this test, the HTSPRTs were transported to NMIJ, where the same repeated measurements at the silver point were done at NMIJ. These were then repeated at CHINO and at NMIJ upon repeated transportation among the institutes, to evaluate some effect due to transportation. This paper reports the details of the above-mentioned tests, the results and the analysis.

Monitoring of high temperature zone by resistivity tomography during in-situ heater test in sedimentary soft rocks

International Nuclear Information System (INIS)

Kubota, Kenji; Suzuki, Koichi; Ikenoya, Takafumi; Takakura, Nozomu; Tani, Kazuo

2008-01-01

In-situ heater test has been conducted to evaluate the influence of high temperature in an underground facility at a depth of 50 m. Resistivity monitoring is thought to be effective to map the extent of the high temperature zone. So we have conducted resistivity tomography during the heater test. As a result, low resistivity zone was appeared near the heated area as starting the heating, and the zone was expanded. Resistivity of rock is proportional to resistivity of pore water. It is known that pore water resistivity decreases as the temperature rise. This suggests that high temperature zone is detected and spatial distribution of temperature can be mapped by resistivity tomography. (author)

Temperature effect on crack resistance and fracture micromechanisms in tungsten-copper pseudoalloy

International Nuclear Information System (INIS)

Babak, A.V.; Gopkalo, E.E.; Krasovskij, A.Ya.; Nadezhdin, G.N.; Uskov, E.I.

1988-01-01

Results of the mechanical- and-physical study of peculiarities of the tungsten-copper pseudoalloy fracture in the temperature range of 293-2273 K are presented. It is shown that the studied material possesses maximum crack resistance in the vicinity of the upper temperature range boundary of the ductile-brittle transition and minimum resistance to cracks propagation when it contains melted copper. It is established that the peculiarities of changes in crack-resistance correspond to peculiarities of fracture micromechanisms for tungsten-copper pseudoalloy in the studied tempearture range

Study of low noise preamplifier systems for use with room temperature mercuric iodide (HgI2) x-ray detectors

International Nuclear Information System (INIS)

Iwanczyk, J.S.; Dabrowski, A.J.; Huth, G.C.; Del Duca, A.; Schenpple, W.

1980-01-01

An analysis of different preamplification systems for use with room temperature mercuric iodide x-ray detectors has been performed. Resistor-, drain-, and light-feedback preamplifiers have been studied. Energy resolution of 295 eV (FWHM) for Fe-55 source (5.9 keV) and 225 eV (FWHM) for the pulser have been obtained with both the detector and the input FET at room temperature using the pulsed-light feedback preamplifier. It has been shown that cooling the input FET using a small Peltier element allows the energy resolution to be improved up to 25%

Anomalous low temperature resistivity in CeCr0.8V0.2Ge3

Science.gov (United States)

Singh, Durgesh; Patidar, Manju Mishra; Mishra, A. K.; Krishnan, M.; Ganesan, V.

2018-04-01

Resistivity (8T) and heat capacity (0T) of CeCr0.8V0.2Ge3 at low temperatures and high magnetic fields are reported. Resistivity curve shows a Kondo like behavior at an anomalously high temperature of 250K. A broad peak at 20K is observed in resistivity. A sharp change in resistivity around 7.3K is due to magnetic ordering mediated by coherence effects. Similar low temperature peak is also observed in heat capacity around 7.2K. A small magnetic field of the order of 1T shifts the peak towards lower temperatures confirming the antiferromagnetic ordering. A broad feature, which appears in resistivity at 20K, is absent in heat capacity. This feature shift towards higher temperatures with magnetic field, and may be due to the partial ferromagnetic ordering or due to geometrical frustration which opposes the magnetic ordering. The system shows a moderate heavy fermion behavior with Sommerfeld coefficient (γ) of 111mJ/mol-K2. Debye temperature of the compound is 250K. Shifting of TN in magnetic fields towards 0K indicates a possibility of quantum criticality in this system.

Temperature influence and reset voltage study of bipolar resistive ...

Indian Academy of Sciences (India)

Moreover, the Cu/ZrO2/ATO device which the ZrO2 thin film annealed at 300 °C can be measured as resistive switching sweeps at 200, 100 and 50 K. It was found that the ratio of off/on reduced when the measured temperature decreased. When the - measurement temperature decreases, on decreases obviously ...

Advances on micro-RWELL gaseous detector

CERN Document Server

Morello, Gianfranco; Benussi, L; De Simone, P; Felici, G; Gatta, M; Poli Lener, M; De Oliveira, R; Ochi, A; Borgonovi, L; Giacomelli, P; Ranieri, A; Valentino, V; Ressegotti, M; Vai, I

2017-01-01

The R&D; on the micro-Resistive-WELL ($\\mu$-RWELL) detector technology aims in developing a new scalable, compact, spark-protected, single amplification stage Micro-Pattern Gas Detectors (MPGD) for large area HEP applications as tracking and calorimeter device as well as for industrial and medical applications as X-ray and neutron imaging gas pixel detector. The novel micro- structure, exploiting several solutions and improvements achieved in the last years for MPGDs, in particular for GEMs and Micromegas, is an extremely simple detector allowing an easy engineering with consequent technological transfer toward the photolithography industry. Large area detectors (up $1 \\times 2 m^2$) can be realized splicing $\\mu$-RWELL_PCB tiles of smaller size (about $0.5 \\times 1 m^2$ - typical PCB industrial size). The detector, composed by few basic elements such as the readout-PCB embedded with the amplification stage (through the resistive layer) and the cathode defining the gas drift-conversion gap has been largel...

Diffusion barrier coatings for high temperature corrosion resistance of advanced carbon/carbon composites

International Nuclear Information System (INIS)

Singh Raman, K.S.

2000-01-01

Carbon possesses an excellent combination of mechanical and thermal properties, viz., excellent creep resistance at temperatures up to 2400 deg C in non-oxidizing environment and a low thermal expansion coefficient. These properties make carbon a potential material for very high temperature applications. However, the use of carbon materials at high temperatures is considerably restricted due to their extremely poor oxidation resistance at temperatures above 400 deg C. The obvious choice for improving high temperature oxidation resistance of such materials is a suitable diffusion barrier coating. This paper presents an overview of recent developments in advanced diffusion- and thermal-barrier coatings for ceramic composites, with particular reference to C/C composites. The paper discusses the development of multiphase and multi-component ceramic coatings, and recent investigations on the oxidation resistance of the coated C/C composites. The paper also discusses the cases of innovative engineering solutions for traditional problems with the ceramic coatings, and the scope of intelligent processing in developing coatings for the C/C composites. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

Undepleted silicon detectors

International Nuclear Information System (INIS)

Rancoita, P.G.; Seidman, A.

1985-01-01

Large-size silicon detectors employing relatively low resistivity material can be used in electromagnetic calorimetry. They can operate in strong magnetic fields, under geometric constraints and with microstrip detectors a high resolution can be achieved. Low noise large capacitance oriented electronics was developed to enable good signal-to-noise ratio for single relativistic particles traversing large area detectors. In undepleted silicon detectors, the charge migration from the field-free region has been investigated by comparing the expected peak position (from the depleted layer only) of the energy-loss of relativistic electrons with the measured one. Furthermore, the undepleted detectors have been employed in a prototype of Si/W electromagnetic colorimeter. The sensitive layer was found to be systematically larger than the depleted one

Characterising large area silicon drift detectors with MOS injectors

International Nuclear Information System (INIS)

Bonvicini, V.; Rashevsky, A.; Vacchi, A.

1999-01-01

In the framework of the INFN DSI project, the first prototypes of a large-area Silicon Drift Detector (SDD) have been designed and produced on 5'' diameter wafers of Neutron Transmutation Doped (NTD) silicon with a resistivity of 3000 Ω·cm. The detector is a 'butterfly' bi-directional structure with a drift length of 32 mm and the drifting charge is collected by two arrays of anodes having a pitch of 200 μm. The high-voltage divider is integrated on-board and is realised with p + implantations. For test and calibration purposes, the detector has a new type of MOS injector. The paper presents results obtained to injecting charge at the maximum drift distance (32mm) from the anodes by means of the MOS injecting structure, As front-end electronics, the authors have used a 32-channels low-noise bipolar VLSI circuit (OLA, Omni-purpose Low-noise Amplifer) specifically designed for silicon drift detectors. The uniformity of the drift time in different regions of the sensitive area and its dependence on the ambient temperature are 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)

On-line monitoring of resistance of aqueous solutions at high temperature

International Nuclear Information System (INIS)

Hu Shilin; Zhang Pingzhu; Shang Weiguo

1999-01-01

The coulostatic measurement is a fast speed electrochemical test method. By this technology, analyzing Δ E(t)- T curves recorded under coulostatic perturbation, the solution resistance R l , resistance of coated film R f , capacity of coated film C f , Polarization resistance R p and double layer capacity C d are obtained. The resistance variety of 0.05N KCl is measured from room temperature up to 255 deg. C under saturation steam pressure. (author)

Thermal simulations of the new design for the BELLE silicon vertex detector

International Nuclear Information System (INIS)

Dragic, J.

2000-01-01

Full text: The experienced imperfections of the BELLE silicon vertex detector, SVD1 motioned the design of a new detector, SVD2, which targets on improving the main weaknesses encountered in the old design. In this report we focus on tile thermal aspects of the SVD2 ladder, whereby sufficient cooling of the detector is necessary in order to minimise the detector leakage currents. It is estimated that reducing the temperature of the silicon detector from 25 deg C to 15 deg C would result in a 50% reduction in leak current. Further, cooling the detector would help minimize mechanical stresses from the thermal cycling. Our task is to ensure that the heat generated by the readout chips is conducted down the SVD hybrid unit effectively, such that the chip and the hybrid temperature does not overbear the SVD silicon sensor temperature. We considered the performance of two materials to act as a heat spreading plate which is glued between the two hybrids in order to improve the heat conductivity of the hybrid unit, namely Copper and Thermal Pyrolytic Graphite (TPG). The effects of other ladder components were also considered in order to enhance the cooling of the silicon detectors. Finite element analysis with ANSYS software was used to simulate the thermal conditions of the SVD2 hybrid unit, in accordance with the baseline design for the mechanical structure of the ladder. It was found that Cu was a preferred material as it achieved equivalent silicon sensor cooling (3.6 deg C above cooling point), while its mechanical properties rendered it a lot more practical. Suppressing, the thermal path via a rib support block, by increasing its thermal resistivity, as well as increasing thermal conductivity of the ribs in the hybrid region, were deemed essential in the effective cooling of the silicon sensors

Silicon drift detectors with on-chip electronics for x-ray spectroscopy.

Science.gov (United States)

Fiorini, C; Longoni, A; Hartmann, R; Lechner, P; Strüder, L

1997-01-01

The silicon drift detector (SDD) is a semiconductor device based on high resistivity silicon fully depleted through junctions implanted on both sides of the semiconductor wafer. The electrons generated by the ionizing radiation are driven by means of a suitable electric field from the point of interaction toward a collecting anode of small capacitance, independent of the active area of the detector. A suitably designed front-end JFET has been directly integrated on the detector chip close to the anode region, in order to obtain a nearly ideal capacitive matching between detector and transistor and to minimize the stray capacitances of the connections. This feature allows it to reach high energy resolution also at high count rates and near room temperature. The present work describes the structure and the performance of SDDs specially designed for high resolution spectroscopy with soft x rays at high detection rate. Experimental results of SDDs used in spectroscopy applications are also reported.

A 20mK temperature sensor

International Nuclear Information System (INIS)

Wang, N.; Sadoulet, B.; Shutt, T.

1987-11-01

We are developing a 20mK temperature sensor made of neutron transmutation doped (NTD) germanium for use as a phonon detector in a dark matter search. We find that NTD germanium thermistors around 20mK have resistances which are a strong function of temperature, and have sufficient sensitivity to eventually reach a base line rms energy fluctuation of 6eV at 25mK. Further work is needed to understand the extreme sensitivity of the thermistors to bias power. 13 refs., 18 figs

Temperature-sensitive junction transformations for mid-wavelength HgCdTe photovoltaic infrared detector arrays by laser beam induced current microscope

Energy Technology Data Exchange (ETDEWEB)

Qiu, Weicheng [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Hu, Weida, E-mail: wdhu@mail.sitp.ac.cn; Lin, Tie; Yin, Fei; Zhang, Bo; Chen, Xiaoshuang; Lu, Wei [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Cheng, Xiang' ai, E-mail: xiang-ai-cheng@126.com; Wang, Rui [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

2014-11-10

In this paper, we report on the disappearance of the photosensitive area extension effect and the unusual temperature dependence of junction transformation for mid-wavelength, n-on-p HgCdTe photovoltaic infrared detector arrays. The n-type region is formed by B{sup +} ion implantation on Hg-vacancy-doped p-type HgCdTe. Junction transformations under different temperatures are visually captured by a laser beam induced current microscope. A physical model of temperature dependence on junction transformation is proposed and demonstrated by using numerical simulations. It is shown that Hg-interstitial diffusion and temperature activated defects jointly lead to the p-n junction transformation dependence on temperature, and the weaker mixed conduction compared with long-wavelength HgCdTe photodiode contributes to the disappearance of the photosensitive area extension effect in mid-wavelength HgCdTe infrared detector arrays.

Real-time particle volume fraction measurement in centrifuges by wireless electrical resistance detector

International Nuclear Information System (INIS)

Nagae, Fumiya; Okawa, Kazuya; Matsuno, Shinsuke; Takei, Masahiro; Zhao Tong; Ichijo, Noriaki

2015-01-01

In this study, wireless electrical resistance detector is developed as first step in order to develop electrical resistance tomography (ERT) that are attached wireless communication, and miniaturized. And the particle volume fraction measurement results appropriateness is qualitatively examined. The real-time particle volume fraction measurement is essential for centrifuges, because rotational velocity and supply should be controlled based on the results in order to obtain the effective separation, shorten process time and save energy. However, a technique for the particle volume fraction measurement in centrifuges has not existed yet. In other words, the real-time particle volume fraction measurement in centrifuges becomes innovative technologies. The experiment device reproduces centrifugation in two-phase using particle and salt solution as measuring object. The particle concentration is measured changing rotational velocity, supply and measurement section position. The measured concentration changes coincide with anticipated tendency of concentration changes. Therefore the particle volume fraction measurement results appropriateness are qualitatively indicated. (author)

Local polarization phenomena in In-doped CdTe x-ray detector arrays

International Nuclear Information System (INIS)

Sato, Toshiyuki; Sato, Kenji; Ishida, Shinichiro; Kiri, Motosada; Hirooka, Megumi; Yamada, Masayoshi; Kanamori, Hitoshi

1995-01-01

Local polarization phenomena have been studied in detector arrays with the detector element size of 500 microm x 500 microm, which are fabricated from high-resistivity In-doped CdTe crystals grown by the vertical Bridgman technique. It has been found for the first time that a polarization effect, which is characterized by a progressive decrease of the pulse counting rate with increasing photon fluence, strongly depends on the detector elements, that is, the portion of crystals used. The influence of several parameters, such as the applied electric field strength, time, and temperature, on this local polarization effect is also investigated. From the photoluminescence measurements of the inhomogeneity of In dopant, it is concluded that the local polarization effect observed here originates from a deep level associated with In dopant in CdTe crystals

NEET Enhanced Micro Pocket Fission Detector for High Temperature Reactors - FY15 Status Report

Energy Technology Data Exchange (ETDEWEB)

Unruh, Troy [Idaho National Lab. (INL), Idaho Falls, ID (United States); McGregor, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ugorowski, Phil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Reichenberger, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ito, Takashi [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-09-01

A new project, that is a collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Atomic Energy Agency, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), has been initiated by the Nuclear Energy Enabling Technologies (NEET) Advanced Sensors and Instrumentation (ASI) program for developing and testing High Temperature Micro-Pocket Fission Detectors (HT MPFD), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package for temperatures up to 800 °C. The MPFD technology utilizes a small, multi-purpose, robust, in-core parallel plate fission chamber and thermocouple. As discussed within this report, the small size, variable sensitivity, and increased accuracy of the MPFD technology represent a revolutionary improvement over current methods used to support irradiations in US Material Test Reactors (MTRs). Previous research conducted through NEET ASI1-3 has shown that the MPFD technology could be made robust and was successfully tested in a reactor core. This new project will further the MPFD technology for higher temperature regimes and other reactor applications by developing a HT MPFD suitable for temperatures up to 800 °C. This report summarizes the research progress for year one of this three year project. Highlights from research accomplishments include: A joint collaboration was initiated between INL, KSU, and CEA. Note that CEA is participating at their own expense because of interest in this unique new sensor. An updated HT MPFD design was developed. New high temperature-compatible materials for HT MPFD construction were procured. Construction methods to support the new design were evaluated at INL. Laboratory evaluations of HT MPFD were initiated. Electrical contact and fissile material plating has been performed at KSU. Updated detector electronics are undergoing evaluations at KSU. A

Heat resistance of Fe-Al intermetallics in the context of selected heat-resistant and hihg-temperature creep resistant steels

Directory of Open Access Journals (Sweden)

P. Baranowski

2009-04-01

Full Text Available Results are hereby presented of heat-resistance tests of two Fe3Al and FeAl intermetallic phase-based alloys in the context of St41k-typeboiler steel and 50H21G9N4 high-temperature creep resistant steel. It has been ascertained that heat resistance of the 50H21G9N4 steeland of the Fe3Al and FeAl intermetallic phase-based alloys significantly exceeds that of the boiler steel tested in the air atmosphere and the atmosphere of a flue gas with CO, CO2, SiO2 content alike. Improvement of these properties depends of exposure conditions. The largest differences have been observed when the tests were carried out in temperature 1023 K and in the flue gas atmosphere. The differences have been more and more noticeable as the exposition duration extended. A tendency has been also recorded of smaller mass decrements of the Fe3Al and FeAl intermetallic phase-based alloys as compared to the 50H21G9N4 steel.

A TWO-DIMENSIONAL POSITION SENSITIVE SI(LI) DETECTOR

Energy Technology Data Exchange (ETDEWEB)

Walton, Jack T.; Hubbard, G. Scott; Haller, Eugene E.; Sommer, Heinrich A.

1978-11-01

Circular, large-area two-dimensional Si(Li) position sensitive detectors have been fabricated. The detectors employ a thin lithium-diffused n{sup +} resistive layer for one contact and a boron implanted p{sup +} resistive layer for the second contact. A position resolution of the order of 100 {micro}m is indicated.

Fast Resistive Bolometer

International Nuclear Information System (INIS)

Deeney, C.; Fehl, D.L.; Hanson, D.L.; Keltner, N.R.; McGurn, J.S.; McKenney, J.L.; Spielman, R.B.

1999-01-01

Resistive bolometry is an accurate, robust, spectrally broadband technique for measuring absolute x-ray fluence and flux. Bolometry is an independent technique for x-ray measurements that is based on a different set of physical properties than other diagnostics such as x-ray diodes, photoconducting detectors, and P-I-N diodes. Bolometers use the temperature-driven change in element resistivity to determine the total deposited energy. The calibration of such a device is based on fundamental material properties and its physical dimensions. We describe the use of nickel and gold bolometers to measure x rays generated by high-power z pinches on Sandia's Saturn and Z accelerators. The Sandia bolometer design described herein has a pulse response of ∼1 ns. We describe in detail the fabrication, fielding, and data analysis issues leading to highly accurate x-ray measurements. The fundamental accuracy of resistive bolometry will be discussed

Fluctuations and dark count rates in superconducting NbN single-photon detectors

International Nuclear Information System (INIS)

Engel, Andreas; Semenov, Alexei; Huebers, Heinz-Wilhelm; Il'in, Kostya; Siegel, Michael

2005-01-01

We measured the temperature- and current-dependence of dark count rates of a superconducting singlephoton detector. The detector's key element is a 84 nm wide meander strip line fabricated from a 5 nm thick NbN film. Due to its reduced dimensions various types of fluctuations can cause temporal and localized transitions into a resistive state leading to dark count events. Adopting a recent refinement of the hotspot model we achieve a satisfying description of the experimental dark count rates taking into account fluctuations of the Cooper-pair density and current-assisted unbinding of vortex-antivortex pairs. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Assembly, characterization, and operation of large-scale TES detector arrays for ACTPol

Science.gov (United States)

Pappas, Christine Goodwin

2016-01-01

The Polarization-sensitive Receiver for the Atacama Cosmology Telescope (ACTPol) is designed to measure the Cosmic Microwave Background (CMB) temperature and polarization anisotropies on small angular scales. Measurements of the CMB temperature and polarization anisotropies have produced arguably the most important cosmological data to date, establishing the LambdaCDM model and providing the best constraints on most of its parameters. To detect the very small fluctuations in the CMB signal across the sky, ACTPol uses feedhorn-coupled Transition-Edge Sensor (TES) detectors. A TES is a superconducting thin film operated in the transition region between the superconducting and normal states, where it functions as a highly sensitive resistive thermometer. In this thesis, aspects of the assembly, characterization, and in-field operation of the ACTPol TES detector arrays are discussed. First, a novel microfabrication process for producing high-density superconducting aluminum/polyimide flexible circuitry (flex) designed to connect large-scale detector arrays to the first stage of readout is presented. The flex is used in parts of the third ACTPol array and is currently being produced for use in the AdvACT detector arrays, which will begin to replace the ACTPol arrays in 2016. Next, we describe methods and results for the in-lab and on-telescope characterization of the detectors in the third ACTPol array. Finally, we describe the ACTPol TES R(T,I) transition shapes and how they affect the detector calibration and operation. Methods for measuring the exact detector calibration and re-biasing functions, taking into account the R(T,I) transition shape, are presented.

Development of gallium arsenide gamma spectrometric detector

International Nuclear Information System (INIS)

Kobayashi, T.; Kuru, I.

1975-03-01

GaAs semiconductor material has been considered to be a suitable material for gamma-ray spectrometer operating at room temperature since it has a wid-band gap, larger than that of silicon and germanium. The basic objective of this work is to develop a GaAs gamma-ray spectrometric detector which could be used for gamma spectrometric measurement of uranium and plutonium in nuclear fuel safeguards. Liquid phase epitaxial techniques using iron (Fe) as dopant have been developed in making high purity GaAs crystals suitable for gamma-ray spectrometer operating at room temperature. Concentration of Fe in the epitaxial crystal was controlled by initial growth temperature. The best quality epitaxial crystal was obtained under the following conditions: starting temperature is about 800degC, the proportion of Fe to Ga solvent is 1 to 300. Carrier concentration of epitaxial crystals grown distributed in the ranges of 10 12 cm -3 to 10 14 cm -3 at room temperature. The thickness of the crystals ranged from 38 μm to 120 μm. Au-GaAs surface barrier detector was made of epitaxial crystal. Some of the detector were encapsulated in a can with a 50 μm Be window by welding a can to the detector holder. The detector with high energy resolution and good charge collecting characteristics was selected by alpha spectrometry at room temperature. Energy resolution of the detector for gamma-rays up to about 200 keV was very good at room temperature operation. The best energy resolutions taken with a GaAs detector were 3 keV (fwhm) and 3.8 keV for 241 Am 59.6 keV and 57 Co 122 keV, respectively, at room temperature. In order to study the applicability of the detector for nuclear safeguards, the measurements of 235 U gamma-ray spectrum have been carried out at room temperature. It was clarified that the gamma-ray spectrum of enriched U sample could be measured in high resolution with GaAs detector at room temperature, and that the content of 235 U in enriched U sources could be determined by

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 ...

Studies on discharges in Micro Pattern Gaseous Detectors, towards a spark resistant THGEM detector

CERN Document Server

Cantini, Cosimo; De Oliveira, Rui

The problem afflicting any of MPGDs is the phenomenon of discharging which might be destructive in some highly energetic cases, at least being responsible of a slow aging of the detector. So far one solution has been cascading several gain elements (GEM, THGEM detectors) reducing the gain of each one; this method, spreading the charges along their path, reduce effectively the likelihood of a discharge but introduce more material due to the multiple stages of amplification. Our goal is developing a single stage THGEM detector which could withstand discharges, not reducing the gain, hence being still able to amplify low level ionizing particles while implementing some methodologies to reduce the damages due to discharge induced by high rate of particles’ flux and/or highly ionizing particles. This report describes the test bench set up to study discharges between simple structures, which are actually models of the bigger detector. The idea behind this approach is to reduce the complexity of the whole phenomen...

The noise analysis and optimum filtering techniques for a two-dimensional position sensitive orthogonal strip gamma ray detector employing resistive charge division

International Nuclear Information System (INIS)

Gerber, M.S.; Muller, D.W.

1976-01-01

The analysis of an orthogonal strip, two-dimensional position sensitive high purity germanium gamma ray detector is discussed. Position sensitivity is obtained by connecting each electrode strip on the detector to a resistor network. Charge, entering the network, divides in relation to the resistance between its entry point and the virtual earth points of the charge sensitive preamplifiers located at the end of each resistor network. The difference of the voltage pulses at the output of each preamplifier is proportional to the position at which the charge entered the resistor network and the sum of the pulse is proportional to the energy of the detected gamma ray. The analysis and spatial noise resolution is presented for this type of position sensitive detector. The results of the analysis show that the position resolution is proportional to the square root of the filter amplifier's output pulse time constant and that for energy measurement the resolution is maximized at the filter amplifier's noise corner time constant. The design of the electronic noise filtering system for the prototype gamma ray camera was based on the mathematical energy and spatial resolution equations. For the spatial channel a Gaussian trapezoidal filtering system was developed. Gaussian filtering was used for the energy channel. The detector noise model was verified by taking rms noise measurements of the filtered energy and spatial pulses from resistive readout charge dividing detectors. These measurements were within 10% of theory. (Auth.)

Very high resolution detection of gamma radiation at room-temperature using P-I-N detectors of CdZnTe and HgCdTe

Science.gov (United States)

Hamilton, W. J.; Rhiger, D. R.; Sen, S.; Kalisher, M. H.; James, K.; Reid, C. P.; Gerrish, V.; Baccash, C. O.

1994-08-01

High-energy photon detectors have been constructed by engineering and fabricating p-i-n diode structures consisting of bulk CdZnTe and epitaxial HgCdTe. The p-i-n structure was obtained by liquid-phase epitaxial growth of p and n doped HgCdTe layers on 'intrinsic' CdZnTe material about 1mm thick and approximately 25mm square. Curve tracing shows I-V curves with diode characteristics having resistivity above 1011 Omega -cm and leakage current of less than 400 pA to about - 60V reverse bias on a typical test piece approximately 5 x 8 x 1 mm. Spectra of similar test pieces have been obtained at room temperature with various nuclear isotopic sources over the range of 22 keV to 662 keV which show exceptionally high energy resolution. Resolution as good as 1.82% FWHM was obtained for the 356 keV line of 133Ba with a P/V = 3.4. The performance of these detectors combined with contemporary infrared technology capable of fabricating 2D arrays of these II-VI materials opens up manifold exciting applications in astrophysics, medical, industrial, environmental, and defense spectroscopy and imaging.

Universal linear-temperature resistivity: possible quantum diffusion transport in strongly correlated superconductors.

Science.gov (United States)

Hu, Tao; Liu, Yinshang; Xiao, Hong; Mu, Gang; Yang, Yi-Feng

2017-08-25

The strongly correlated electron fluids in high temperature cuprate superconductors demonstrate an anomalous linear temperature (T) dependent resistivity behavior, which persists to a wide temperature range without exhibiting saturation. As cooling down, those electron fluids lose the resistivity and condense into the superfluid. However, the origin of the linear-T resistivity behavior and its relationship to the strongly correlated superconductivity remain a mystery. Here we report a universal relation [Formula: see text], which bridges the slope of the linear-T-dependent resistivity (dρ/dT) to the London penetration depth λ L at zero temperature among cuprate superconductor Bi 2 Sr 2 CaCu 2 O 8+δ and heavy fermion superconductors CeCoIn 5 , where μ 0 is vacuum permeability, k B is the Boltzmann constant and ħ is the reduced Planck constant. We extend this scaling relation to different systems and found that it holds for other cuprate, pnictide and heavy fermion superconductors as well, regardless of the significant differences in the strength of electronic correlations, transport directions, and doping levels. Our analysis suggests that the scaling relation in strongly correlated superconductors could be described as a hydrodynamic diffusive transport, with the diffusion coefficient (D) approaching the quantum limit D ~ ħ/m*, where m* is the quasi-particle effective mass.

Introduction or 'Low-temperature detectors: yesterday, today and tomorrow'

International Nuclear Information System (INIS)

Fiorini, E.

2004-01-01

I would like first to express my deep gratitude to Flavio Gatti and to the Organizing committee for inviting me to introduce the tenths of these Workshops, which have become more and more stimulating with years. I cannot avoid to emphasize how much I miss, and I am sure we all miss, Sandro Vitale, who started this activity in Genoa. He was for me not only a dear friend, but also, despite our similar ages, an inspiring teacher. I cannot obviously review what will be reported in this week here, which looks already very exciting just at a glance to the program. I will limit myself to some personal recollection and to some arguments which I personally see of great interest for the application of low-temperature detectors in nuclear, subnuclear and astroparticle physics

Microfluidic Scintillation Detectors

CERN Multimedia

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

Wear resistance of AISI 304 stainless steel submitted to low temperature plasma carburizing

Directory of Open Access Journals (Sweden)

Marcos Antônio Barcelos

Full Text Available Abstract Despite the AISI 304 stainless steel has high corrosion/oxidation resistance, its tribological properties are poor, being one of the barriers for use in severe wear applications. Thus, there is a wide field for studying technologies that aim to increase the surface hardness and wear resistance of this material. In this work, hardness and wear resistance for AISI 304 stainless steel submitted to the thermochemical treatment by low temperature plasma carburizing (LTPC in a fixed gas mixture composition of 93% H2 and 7% CH4 are presented. Through the evaluation of the carburizing layers, it was possible to observe a substantial improvement in tribological properties after all temperature and time of treatment. This improvement is directly related to the increase of the process variables; among them temperature has a stronger influence on the wear resistance obtained using LTPC process.

Halogen effect for improving high temperature oxidation resistance of Ti-50Al by anodization

Science.gov (United States)

Mo, Min-Hua; Wu, Lian-Kui; Cao, Hua-Zhen; Lin, Jun-Pin; Zheng, Guo-Qu

2017-06-01

The high temperature oxidation resistance of Ti-50Al was significantly improved via halogen effect which was achieved by anodizing in an ethylene glycol solution containing with fluorine ion. The anodized Ti-50Al with holes and micro-cracks could be self-repaired during oxidation at 1000 °C. The thickness of the oxide scale increases with the prolonging of oxidation time. On the basis of halogen effect for improving the high temperature oxidation resistance of Ti-50Al by anodization, only fluorine addition into the electrolyte can effectively improve the high temperature oxidation resistance of Ti-50Al.

Ageing studies of resistive Micromegas detectors for the HL-LHC

CERN Document Server

Galán, J; Ferrer-Ribas, E; Giganon, A; Giomataris, I; Herlant, S; Jeanneau, F; Peyaud, A; Schune, Ph; Alexopoulos, T; Byszewski, M; Iakovidis, G; Iengo, P; Ntekas, K; Leontsinis, S; de Oliveira, R; Tsipolitis, Y; Wotschack, J

2013-01-01

Resistive-anode Micromegas detectors are in development since several years, in an effort to solve the problem of sparks when working in high flux and high radiations environment like in the HL-LHC (ten times the luminosity of the LHC). They have been chosen as one of the technologies that will be part of the ATLAS New Small Wheel project (forward muon system). An ageing study is mandatory to assess their capabilities to handle the HL-LHC environment on a long-term period. A prototype has been exposed to several types of irradiations (X-rays, cold neutrons, 60 Co gammas) up to an equivalent HL-LHC time of more than five years without showing any degradation of the performances in terms of gain and energy resolution. Beam test studies took place in October 2012 to assess the tracking performances (efficiency, spatial resolution,...). Results of ageing studies and beam test performances are reported in this paper.

Current state-of-the-art industrial and research applications using room-temperature CdTe and CdZnTe solid state detectors

International Nuclear Information System (INIS)

Eisen, Y.

1996-01-01

Improvements of CdTe crystal quality and significant progress in the growth of large ingots of high resistivity CdZnTe material enable the fabrication of larger area detectors in single element form or monolithic arrays. These advances allow for the development of imaging devices of improved spatial resolution for industrial, research and medical applications. CdTe and CdZnTe detectors operate in single photon counting mode or in current mode (charge integrating mode). The paper presents advantages of CdTe and CdZnTe over common scintillator type detectors, but also presents the shortcomings of the former detectors with respect to charge collection which limit the yields of good spectrometers. The paper reviews industrial and research applications utilizing these detectors and in particular describes in detail two imaging systems for security screening and custom inspection. These systems are characterized by large dynamic range and good spatial resolution and are composed of large arrays of CdTe spectrometers and discriminator grade detectors. A wide energy range detector assembly, for astrophysical research of gamma ray bursts composed of CdTe, HgI 2 and CdZnTe spectrometers in two dimensional arrays is also presented. (orig.)

Detectors - Electronics

International Nuclear Information System (INIS)

Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.

1998-01-01

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

Detector unit for X-ray diagnosis

International Nuclear Information System (INIS)

Svobodova, B.; Hamouz, J.; Pavlicek, Z.; Jursova, L.; Pohanka, J.

1983-01-01

The detector unit is applied in the medical and industrial X-ray diagnosis and analysis. It controls the X-ray dosing by exposure and brightness automation. The detector field is generated from a carrier, in which detector elements with light quides are situated, tapped on optical detectors with level converters outside the detector field. The detector field and the optical detectors with level converters are located in a light-resistent shell. This arrangement of the detector unit allows to use the impulse skiascopy instead of permanent X-ray examinations or the skiagraphy with multienergy levels which considerably improves the diagnostic value of the exposures and the working conditions. 1 cl., 1 fig

Effect of Low Temperature on a 4 W/60 K Pulse-Tube Cryocooler for Cooling HgCdTe Detector

Science.gov (United States)

Zhang, Ankuo; Liu, Shaoshuai; Wu, Yinong

2018-04-01

Temperature is an extremely important parameter for the material of the space-borne infrared detector. To cool an HgCdTe-infrared detector, a Stirling-type pulse-tube cryocooler (PTC) has been developed based on a great deal of numerical simulations, which are performed to investigate the thermodynamic behaviors of the PTC. The effects of different low temperatures are presented to analyze different energy flows, losses, phase shifts, and impedance matching of the PTC at a temperature range of 40-120 K, where woven wire screens are used. Finally, a high-efficiency coaxial PTC has been designed, built, and tested, operating around 60 K after a number of theoretical and experimental studies. The PTC can offer a no-load refrigeration temperature of 40 K with an input electric power of 150 W, and a cooling power of 4 W at 60 K is obtained with Carnot efficiency of 12%. In addition, a comparative study of simulation and experiment has been carried out, and some studies on reject temperatures have been presented for a thorough understanding of the PTC system.

Radiation detection at very low temperature. DRTBT 1991 Aussois - Course collection

International Nuclear Information System (INIS)

Salce, B.; Godfrin, H.; Dumoulin, L.; Garoche, Pierre; Pannetier, B.; Equer, B.; Hubert, PH.; Urbina, C.; Lamarre, J.M.; Brison, J.P.; Lesueur, D.; Bret, J.L.; Ayela, F.; Coron, N.; Gonzalez-Mestres, L.

1991-12-01

This publication gather several courses which propose or address: Thermal conduction, Kapitza resistance, Metal-insulator transition, Thermal properties and specific heat at low temperature, Thermometry, Low temperature superconductors, Defects due to irradiations in solids, Semiconducting detectors, Techniques of protection of a measurement assembly at low temperatures against perturbations, Noise reduction by impedance matching converter at low temperature, Low noise electronics and measurement, Low radio-activities, SQUID and electrometer, Results and expectations related to bolometers, Infrared and sub-millimetre radiation in astrophysics, Neutrinos, dark matter and heavy ions

Characterization of CdTe and (CdZn)Te detectors with different metal contacts

Science.gov (United States)

Pekárek, J.; Belas, E.; Grill, R.; Uxa, Å.; James, R. B.

2013-09-01

In the present work we studied an influence of different types of surface etching and surface passivation of high resistivity CdZnTe-based semiconductor detector material. The aim was to find the optimal conditions to improve the properties of metal-semiconductor contact. The main effort was to reduce the leakage current and thus get better X-ray and gamma-ray spectrum, i.e. to create a detector operating at room temperature based on this semiconductor material with sufficient energy resolution and the maximum charge collection efficiency. Individual surface treatments were characterized by I-V characteristics, spectral analysis and by determination of the profile of the internal electric field.

Terahertz detectors using hot-electrons in superconducting films

Energy Technology Data Exchange (ETDEWEB)

Semenov, A. [DLR, Inst. of Planetary Research, Berlin (Germany)

2007-07-01

Recently the terahertz gap has been recognized as a prospective spectral range for radioastronomy as well as for material and security studies. Implementation of terahertz technology in these fields requires further improvement of instruments and their major subcomponents. Physical phenomena associated with the local and homogeneous non-equilibrium electron sates in thin superconducting films offer numerous possibilities for the development of terahertz and infrared detectors. Depending on the nature of the resistive state and the operation regime, a variety of detector can be realized. They are e.g. direct bolometric or kinetic inductance detectors, heterodyne mixers or photon counters. Operation principles and physical limitations of these devices will be discussed. Two examples of the detector development made in cooperation between the German Aerospace Center, the University of Karlsruhe and PTB, Berlin will be presented. The energy resolving single-photon detector with an almost fundamentally limited energy resolution of 0.6 eV at 6.5 K for photons with wavelengths from 400 nm to 2500 nm and the heterodyne mixer quasioptically coupled to radiation in the frequency range from 0.8 THz to 5 THz and providing a noise temperature of less then ten times the quantum limit. The mixers will be implemented in the terahertz radar for security screening (TERASEC) and in the heterodyne receiver of the stratospheric observatory SOFIA. (orig.)

Prototyping and performance study of a single crystal diamond detector for operation at high temperatures

Science.gov (United States)

Kumar, Amit; Kumar, Arvind; Topkar, Anita; Das, D.

2017-06-01

Prototype single crystal diamond detectors with different types of metallization and post metallization treatment were fabricated for the applications requiring fast neutron measurements in the Indian Test Blanket Module (TBM) at the International Thermonuclear Experimental Reactor (ITER) Experiment. The detectors were characterized by leakage current measurements to ascertain that the leakage currents are low and breakdown voltages are higher than the voltage required for full charge collection. The detector response to charged particles was evaluated using a 238+239 Pu dual energy alpha source. The detectors showed an energy resolution of about 2% at 5.5 MeV. In order to study their suitability for the operation at higher temperatures, leakage current variation and alpha response were studied up to 300 °C. At 300 °C, peaks corresponding to 5.156 MeV and 5.499 MeV alphas could be separated and there was no significant degradation of energy resolution. Finally, the detector response to fast neutrons was evaluated using a Deuterium-Tritium (D-T) neutron generator. The observed spectrum showed peaks corresponding to various channels of n-C interactions with a clear isolated peak corresponding to 8.5 MeV alphas. The detectors also showed high sensitivity of 3.4×10-2 cps/n/(cm2 s)-4.5×10-2 cps/n/(cm2 s) and excellent linearity of response in terms of count rate at different neutron flux in the observed range of 3.2×105 n/(cm2 s) to 2.0×106 n/(cm2 s).

Superconducting Hot-Electron Submillimeter-Wave Detector

Science.gov (United States)

Karasik, Boris; McGrath, William; Leduc, Henry

2009-01-01

A superconducting hot-electron bolometer has been built and tested as a prototype of high-sensitivity, rapid-response detectors of submillimeter-wavelength radiation. There are diverse potential applications for such detectors, a few examples being submillimeter spectroscopy for scientific research; detection of leaking gases; detection of explosive, chemical, and biological weapons; and medical imaging. This detector is a superconducting-transition- edge device. Like other such devices, it includes a superconducting bridge that has a low heat capacity and is maintained at a critical temperature (T(sub c)) at the lower end of its superconducting-transition temperature range. Incident photons cause transient increases in electron temperature through the superconducting-transition range, thereby yielding measurable increases in electrical resistance. In this case, T(sub c) = 6 K, which is approximately the upper limit of the operating-temperature range of silicon-based bolometers heretofore used routinely in many laboratories. However, whereas the response speed of a typical silicon- based laboratory bolometer is characterized by a frequency of the order of a kilohertz, the response speed of the present device is much higher characterized by a frequency of the order of 100 MHz. For this or any bolometer, a useful figure of merit that one seeks to minimize is (NEP)(tau exp 1/2), where NEP denotes the noise-equivalent power (NEP) and the response time. This figure of merit depends primarily on the heat capacity and, for a given heat capacity, is approximately invariant. As a consequence of this approximate invariance, in designing a device having a given heat capacity to be more sensitive (to have lower NEP), one must accept longer response time (slower response) or, conversely, in designing it to respond faster, one must accept lower sensitivity. Hence, further, in order to increase both the speed of response and the sensitivity, one must make the device very small in

Barrier Infrared Detector (BIRD)

Data.gov (United States)

National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

An instrumentation amplifier based readout circuit for a dual element microbolometer infrared detector

Science.gov (United States)

de Waal, D. J.; Schoeman, J.

2014-06-01

The infrared band is widely used in many applications to solve problems stretching over very diverse fields, ranging from medical applications like inflammation detection to military, security and safety applications employing thermal imaging in low light conditions. At the heart of these optoelectrical systems lies a sensor used to detect incident infrared radiation, and in the case of this work our focus is on uncooled microbolometers as thermal detectors. Microbolometer based thermal detectors are limited in sensitivity by various parameters, including the detector layout and design, operating temperature, air pressure and biasing that causes self heating. Traditional microbolometers use the entire membrane surface for a single detector material. This work presents the design of a readout circuit amplifier where a dual detector element microbolometer is used, rather than the traditional single element. The concept to be investigated is based on the principle that both elements will be stimulated with a similar incoming IR signal and experience the same resistive change, thus creating a common mode signal. However, such a common mode signal will be rejected by a differential amplifier, thus one element is placed within a negative resistance converter to create a differential mode signal that is twice the magnitude of the comparable single mode signal of traditional detector designs. An instrumentation amplifier is used for the final stage of the readout amplifier circuit, as it allows for very high common mode rejection with proper trimming of the Wheatstone bridge to compensate for manufacturing tolerance. It was found that by implementing the above, improved sensitivity can be achieved.

Effect of temperature on the crack resistance of a molybdenum alloy with 30% tungsten

International Nuclear Information System (INIS)

Uskov, E.I.; Babak, A.V.; D'yachkov, A.P.; Platonov, V.A.

1986-01-01

Results are presented for a study of the effect of temperature on the crack resistance of molybdenum alloy with 30% tungsten (Mo - 30% W), and data are presented for the crack resistance of commercial-purity molybdenum and tungsten obtained by power metallurgy in the temperature range 20-1800 C. It was found that the nature of failure for Mo-30% W alloy depends on test temperature; in the temperature range 20 C-T /SUP d/ /SUB br/ (upper boundary for the temperature range of the ductile to brittle transition), failure is unstable in nature, and at temperatures exceeding this transition, it occurs by steady main crack development

Host Resistance and Temperature-Dependent Evolution of Aggressiveness in the Plant Pathogen Zymoseptoria tritici

Directory of Open Access Journals (Sweden)

Fengping Chen

2017-06-01

Full Text Available Understanding how habitat heterogeneity may affect the evolution of plant pathogens is essential to effectively predict new epidemiological landscapes and manage genetic diversity under changing global climatic conditions. In this study, we explore the effects of habitat heterogeneity, as determined by variation in host resistance and local temperature, on the evolution of Zymoseptoria tritici by comparing the aggressiveness development of five Z. tritici populations originated from different parts of the world on two wheat cultivars varying in resistance to the pathogen. Our results show that host resistance plays an important role in the evolution of Z. tritici. The pathogen was under weak, constraining selection on a host with quantitative resistance but under a stronger, directional selection on a susceptible host. This difference is consistent with theoretical expectations that suggest that quantitative resistance may slow down the evolution of pathogens and therefore be more durable. Our results also show that local temperature interacts with host resistance in influencing the evolution of the pathogen. When infecting a susceptible host, aggressiveness development of Z. tritici was negatively correlated to temperatures of the original collection sites, suggesting a trade-off between the pathogen’s abilities of adapting to higher temperature and causing disease and global warming may have a negative effect on the evolution of pathogens. The finding that no such relationship was detected when the pathogen infected the partially resistant cultivars indicates the evolution of pathogens in quantitatively resistant hosts is less influenced by environments than in susceptible hosts.

Optimization of a bolometer detector for ITER based on Pt absorber on SiN membrane

Energy Technology Data Exchange (ETDEWEB)

Meister, H.; Eich, T.; Endstrasser, N.; Giannone, L.; Kannamueller, M.; Kling, A.; Koll, J.; Trautmann, T. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, D-85748 Garching (Germany); Detemple, P.; Schmitt, S. [Institut fuer Mikrotechnik Mainz GmbH, Carl-Zeiss-Str. 18-20, D-55129 Mainz (Germany); Collaboration: ASDEX Upgrade Team

2010-10-15

Any plasma diagnostic in ITER must be able to operate at temperatures in excess of 200 deg. C and neutron loads corresponding to 0.1 dpa over its lifetime. To achieve this aim for the bolometer diagnostic, a miniaturized metal resistor bolometer detector based on Pt absorbers galvanically deposited on SiN membranes is being developed. The first two generations of detectors featured up to 4.5 {mu}m thick absorbers. Results from laboratory tests are presented characterizing the dependence of their calibration constants under thermal loads up to 450 deg. C. Several detectors have been tested in ASDEX Upgrade providing reliable data but also pointing out the need for further optimization. A laser trimming procedure has been implemented to reduce the mismatch in meander resistances below 1% for one detector and the thermal drifts from this mismatch.

Optimization of a bolometer detector for ITER based on Pt absorber on SiN membranea)

Science.gov (United States)

Meister, H.; Eich, T.; Endstrasser, N.; Giannone, L.; Kannamüller, M.; Kling, A.; Koll, J.; Trautmann, T.; ASDEX Upgrade Team; Detemple, P.; Schmitt, S.

2010-10-01

Any plasma diagnostic in ITER must be able to operate at temperatures in excess of 200 °C and neutron loads corresponding to 0.1 dpa over its lifetime. To achieve this aim for the bolometer diagnostic, a miniaturized metal resistor bolometer detector based on Pt absorbers galvanically deposited on SiN membranes is being developed. The first two generations of detectors featured up to 4.5 μm thick absorbers. Results from laboratory tests are presented characterizing the dependence of their calibration constants under thermal loads up to 450 °C. Several detectors have been tested in ASDEX Upgrade providing reliable data but also pointing out the need for further optimization. A laser trimming procedure has been implemented to reduce the mismatch in meander resistances below 1% for one detector and the thermal drifts from this mismatch.

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

High-Temperature Characteristics of an InAsSb/AlAsSb n+Bn Detector

Science.gov (United States)

Ting, David Z.; Soibel, Alexander; Höglund, Linda; Hill, Cory J.; Keo, Sam A.; Fisher, Anita; Gunapala, Sarath D.

2016-09-01

The high-temperature characteristics of a mid-wavelength infrared (MWIR) detector based on the Maimon-Wicks InAsSb/AlAsSb nBn architecture was analyzed. The dark current characteristics are examined in reference to recent minority carrier lifetime results. The difference between the responsivity and absorption quantum efficiency (QE) at shorter wavelengths is clarified in terms of preferential absorption of higher-energy photons in the top contact layer, which cannot provide reverse-bias photo-response due to the AlAsSb electron blocking layer and strong recombination. Although the QE does not degrade when the operating temperature increases to 325 K, the turn-on bias becomes larger at higher temperatures. This behavior was originally attributed to the change in the valence band alignment between the absorber and top contact layers caused by the shift in Fermi level with temperature. In this work, we demonstrated the inadequacy of the original description, and offer a more likely explanation based on temperature-dependent band-bending effects.

Low temperature resistivity plateau and non-saturating magnetoresistance in Type-II Weyl semimetal WP2

Science.gov (United States)

Nagpal, V.; Kumar, P.; Sudesh, Patnaik, S.

2018-04-01

We have studied the resistivity and magnetoresistance (MR) properties of the recently predicted type-II Weyl semimetal WP2. Polycrystalline WP2 is synthesized using solid state reaction and crystallizes in an orthorhombic structure with the Cmc21 spacegroup. The temperature dependent resistivity is enhanced with the application of magnetic field and a resistivity plateau is observed at low temperatures. We find a small dip in resistivity around 30K at 5T field suggesting that there might be a metal-insulator-like transition at higher magnetic fields. A non-saturating magnetoresistance is observed at low temperatures with maximum MR ˜ 94% at 2K and 6T. The value of MR decreases with the increase in temperature. We see a deviation from Kohler's power law which implies that the system comprises of two types of charge carriers.

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...

Low temperature resistivity studies of SmB6: Observation of two-dimensional variable-range hopping conductivity

Science.gov (United States)

Batkova, Marianna; Batko, Ivan; Gabáni, Slavomír; Gažo, Emil; Konovalova, Elena; Filippov, Vladimir

2018-05-01

We studied electrical resistance of a single-crystalline SmB6 sample with a focus on the region of the "low-temperature resistivity plateau". Our observations did not show any true saturation of the electrical resistance at temperatures below 3 K down to 70 mK. According to our findings, temperature dependence of the electrical conduction in a certain temperature interval above 70 mK can be decomposed into a temperature-independent term and a temperature-activated term that can be described by variable-range hopping formula for two-dimensional systems, exp [ -(T0 / T) 1 / 3 ]. Thus, our results indicate importance of hopping type of electrical transport in the near-surface region of SmB6.

Development and evaluation of a HEPA filter for increased strength and resistance to elevated temperature

International Nuclear Information System (INIS)

Gilbert, H.; Bergman, W.; Fretthold, J.K.

1992-01-01

We have developed an improved HEPA filter for increased strength and resistance to elevated temperature to improve the reliability of HEPA filters under accident conditions. The improvements to the HEPA filter consist of a silicone rubber sealant and a new HEPA medium reinforced with a glass cloth. Several prototype filters were built and evaluated for temperature and pressure resistance and resistance to rough handling. The temperature resistance test consisted of exposing the HEPA filter to 1,000 scan at 700 degrees F for five minutes. The pressure resistance test consisted of exposing the HEPA filter to a differential pressure of 10 in. w.g. using a water saturated air flow at 95 degrees F. For the rough handling test, we used a vibrating machine designated the Q110. DOP filter efficiency tests were performed before and after each of the environmental tests. In addition to following the standard practice of using a separate new filter for each environmental test, we also subjected the same filter to the elevated temperature test followed by the pressure resistance test. The efficiency test results show that the improved HEPA filter is significantly better than the standard HEPA filter

Amorphous selenium based detectors for medical imaging applications

Science.gov (United States)

Mandal, Krishna C.; Kang, Sung H.; Choi, Michael; Jellison, Gerald E., Jr.

2006-08-01

We have developed and characterized large volume amorphous (a-) selenium (Se) stabilized alloys for room temperature medical imaging devices and high-energy physics detectors. The synthesis and preparation of well-defined and high quality a-Se (B, As, Cl) alloy materials have been conducted using a specially designed alloying reactor at EIC and installed in an argon atmosphere glove box. The alloy composition has been precisely controlled and optimized to ensure good device performance. The synthesis of large volume boron (B) doped (natural and isotopic 10B) a-Se (As, Cl) alloys has been carried out by thoroughly mixing vacuum distilled and zone-refined (ZR) Se with previously synthesized Se-As master alloys, Se-Cl master alloys and B. The synthesized a-Se (B, As, Cl) alloys have been characterized by x-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infra-red spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectroscopy (ICP-MS), and detector testing. The a- Se alloys have shown high promise for x-ray detectors with its high dark resistivity (10 10-10 13 Ωcm), good charge transport properties, and cost-effective large area scalability. Details of various steps about detector fabrication and testing of these imaging devices are also presented.

Temperature Effect on the Susceptibility of Methicillin-Resistant Staphylococcus aureus to Four Different Cephalosporins

OpenAIRE

Canawati, Hanna N.; Witte, Joyce L.; Sapico, Francisco L.

1982-01-01

Forty isolates of methicillin-resistant Staphylococcus aureus were tested for in vitro susceptibility to cephalothin, cefamandole, cefotaxime, and moxalactam, using the disk diffusion and microbroth dilution methods at incubation temperatures of 30 and 35°C. Resistance to all four antibiotics was more clearly evident at an incubation temperature of 30°C.

Cryostat for an well logging probe using a semiconductor detector

International Nuclear Information System (INIS)

Tapphorn, R.M.

1978-01-01

This invention proposes to construct an well logging tool of the type comprising a semiconductor radiation detector devoid of the defects usually observed. This aim is attained by means of a cryostat to cool a semiconductor radiation detector in a restricted space where the temperature is high. It includes a long box dimensioned to pass through a bore hole, a cryogenic chamber housed in the box, a vacuum chamber thermally insulating the cryogenic chamber and placed around it, a semiconductor radiation detector housed in the vacuum chamber in thermal contact with the cryogenic chamber and an active vacuum pump fitted in the box and connected to the vacuum chamber to maintain a vacuum in it. In an improved version, the vacuum pump is fitted outside the cryostat so that it operates independently of the temperature conditions in the cryostat. If the pump needs to be cooled to reduce the gas discharge, it can be fitted inside the cryostat and connected to the cryogenic chamber or a second cryostat can also be provided to cool the pump. The vacuum pump is designed to maintain the vacuum in the thermal insulation vacuum chamber at a desired figure, preferably 10 -4 Torr or under, in order to preserve the integrity of the thermal insulation layer around the cryogenic chamber and thereby extending the efficient operating period of the detector. The cryogenic material used is preferably of fusion resistant type such as Freon 22 [fr

Electric resistance of nickel and niobium in the temperature range of 300-1300 K

International Nuclear Information System (INIS)

Novikov, I.I.; Roshchupkin, V.V.; Mozgovoj, A.G.; Semashko, N.A.

1982-01-01

The results of experimental investigation of nickel and niobium electric resistance on the wire samples by the potentiometric method in the temperature range of 300-1300 K are presented. Experimental data processing by the least square method is carried out; approximating equations of temperature dependence of the nickel and niobium electric resistance are prepared

Piggyback resistive Micromegas

CERN Document Server

Attié, D; Durand, D; Desforge, D; Ferrer-Ribas, E; Galán, J; Giomataris, Y; Gongadze, A; Iguaz, F J; Jeanneau, F; de Oliveira, R; Papaevangelou, T; Peyaud, A; Teixeira, A

2013-01-01

Piggyback Micromegas consists in a novel readout architecture where the anode element is made of a resistive layer on a ceramic substrate. The resistive layer is deposited on the thin ceramic substrate by an industrial process which provides large dynamic range of resistivity (10$^6$ to 10$^{10}$\\,M$\\Omega$/square). The particularity of this new structure is that the active part is entirely dissociated from the read-out element. This gives a large flexibility on the design of the anode structure and the readout scheme. Without significant loss, signals are transmitted by capacitive coupling to the read-out pads. The detector provides high gas gain, good energy resolution and the resistive layer assures spark protection for the electronics. This assembly could be combined with modern pixel array electronic ASICs. First tests with different Piggyback detectors and configurations will be presented. This structure is adequate for cost effective fabrication and low outgassing detectors. It was designed to perform ...

Effects of ion temperature fluctuations on the stability of resistive ballooning modes

International Nuclear Information System (INIS)

Singh, R.; Nordman, H.; Jarmen, A.; Weiland, J.

1996-01-01

The influence of ion temperature fluctuations on the stability of resistive drift- and ballooning-modes is investigated using a two-fluid model. The Eigenmode equations are derived and solved analytically in a low beta model equilibrium. Parameters relevant to L-mode edge plasmas from the Texas Experimental Tokamak are used. The resistive modes are found to be destabilized by ion temperature fluctuations over a broad range of mode numbers. The scaling of the growth rate with magnetic shear and mode number is elucidated. 13 refs, 4 figs

An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

Energy Technology Data Exchange (ETDEWEB)

Guerra, P; Santos, A [Centro de Investigacion Biomedica de Bioningenieria, Biomateriales y Nanomedicina, CEEI-Modulo 3, C/ Maria de Luna, 11, 50018 Zaragoza (United States); Darambara, D G, E-mail: pguerra@ciber-bbn.e [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Fulham Road, London SW3 6JJ (United Kingdom)

2009-09-07

The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm{sup 3} CdZnTe pixellated detector.

An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

International Nuclear Information System (INIS)

Guerra, P; Santos, A; Darambara, D G

2009-01-01

The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm 3 CdZnTe pixellated detector.

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

Monitoring of high temperature area by resistivity tomography during in-situ heating test in sedimentary soft rocks

International Nuclear Information System (INIS)

Kubota, Kenji; Suzuki, Koichi; Ikenoya, Takafumi; Takakura, Nozomu; Tani, Kazuo

2009-01-01

One of the major issues in disposal of nuclear waste is that the long term behaviors of sedimentary soft rocks can be affected by various environmental factors such as temperature, mechanical conditions or hydraulic conditions. Therefore, it is necessary to develop a method for evaluating the long term stability of caverns in sedimentary soft rocks as subjected to changes of environment. We have conducted in-situ heating test to evaluate the influence of high temperature to the surrounding rock mass at a depth of 50 m. The well with a diameter of 30 cm and 60 cm of height, was drilled and filled with groundwater. The heater was installed in the well for heating the surrounding rock mass. During the heating, temperature and deformation around the well were measured. To evaluate the influence of heating on sedimentary soft rocks, it is important to monitor the extent of heated area. Resistivity monitoring is thought to be effective to map the extent of the high temperature area. So we have conducted resistivity tomography during the heating test. The results demonstrated that the resistivity of the rock mass around the heating well decreased and this area was gradually expanded from the heated area during the heating. The decreasing rate of resistivity on temperature is correlated to that of laboratory experimental result and existing empirical formula between aqueous solution resistivity and temperature. Resistivity is changed by many other factors, but it is expected that resistivity change by other factors is very few in this test. This suggests that high temperature area is detected and spatial distribution of temperature can be mapped by resistivity tomography. So resistivity tomography is expected to be one of the promising methods to monitor the area heated by nuclear waste. (author)

Performance of Multiplexed XY Resistive Micromegas detectors in a high intensity beam

Science.gov (United States)

Banerjee, D.; Burtsev, V.; Chumakov, A.; Cooke, D.; Depero, E.; Dermenev, A. V.; Donskov, S. V.; Dubinin, F.; Dusaev, R. R.; Emmenegger, S.; Fabich, A.; Frolov, V. N.; Gardikiotis, A.; Gninenko, S. N.; Hösgen, M.; Karneyeu, A. E.; Ketzer, B.; Kirsanov, M. M.; Konorov, I. V.; Kramarenko, V. A.; Kuleshov, S. V.; Levchenko, E.; Lyubovitskij, V. E.; Lysan, V.; Mamon, S.; Matveev, V. A.; Mikhailov, Yu. V.; Myalkovskiy, V. V.; Peshekhonov, V. D.; Peshekhonov, D. V.; Polyakov, V. A.; Radics, B.; Rubbia, A.; Samoylenko, V. D.; Tikhomirov, V. O.; Tlisov, D. A.; Toropin, A. N.; Vasilishin, B.; Arenas, G. Vasquez; Ulloa, P.; Crivelli, P.

2018-02-01

We present the performance of multiplexed XY resistive Micromegas detectors tested in the CERN SPS 100 GeV/c electron beam at intensities up to 3 . 3 × 105e- /(s ṡcm2) . So far, all studies with multiplexed Micromegas have only been reported for tests with radioactive sources and cosmic rays. The use of multiplexed modules in high intensity environments was not explored due to the effect of ambiguities in the reconstruction of the hit point caused by the multiplexing feature. For the specific mapping and beam intensities analyzed in this work with a multiplexing factor of five, more than 50% level of ambiguity is introduced due to particle pile-up as well as fake clusters due to the mapping feature. Our results prove that by using the additional information of cluster size and integrated charge from the signal clusters induced on the XY strips, the ambiguities can be reduced to a level below 2%. The tested detectors are used in the CERN NA64 experiment for tracking the incoming particles bending in a magnetic field in order to reconstruct their momentum. The average hit detection efficiency of each module was found to be ∼96% at the highest beam intensities. By using four modules a tracking resolution of 1.1% was obtained with ∼85% combined tracking efficiency.

Prototyping and performance study of a single crystal diamond detector for operation at high temperatures

Energy Technology Data Exchange (ETDEWEB)

Kumar, Amit; Kumar, Arvind; Topkar, Anita, E-mail: anita@barc.gov.in; Das, D.

2017-06-21

Prototype single crystal diamond detectors with different types of metallization and post metallization treatment were fabricated for the applications requiring fast neutron measurements in the Indian Test Blanket Module (TBM) at the International Thermonuclear Experimental Reactor (ITER) Experiment. The detectors were characterized by leakage current measurements to ascertain that the leakage currents are low and breakdown voltages are higher than the voltage required for full charge collection. The detector response to charged particles was evaluated using a {sup 238+239} Pu dual energy alpha source. The detectors showed an energy resolution of about 2% at 5.5 MeV. In order to study their suitability for the operation at higher temperatures, leakage current variation and alpha response were studied up to 300 °C. At 300 °C, peaks corresponding to 5.156 MeV and 5.499 MeV alphas could be separated and there was no significant degradation of energy resolution. Finally, the detector response to fast neutrons was evaluated using a Deuterium-Tritium (D-T) neutron generator. The observed spectrum showed peaks corresponding to various channels of n-C interactions with a clear isolated peak corresponding to ~8.5 MeV alphas. The detectors also showed high sensitivity of 3.4×10{sup −2} cps/n/(cm{sup 2} s)–4.5×10{sup −2} cps/n/(cm{sup 2} s) and excellent linearity of response in terms of count rate at different neutron flux in the observed range of 3.2×10{sup 5} n/(cm{sup 2} s) to 2.0×10{sup 6} n/(cm{sup 2} s).

Coherent Anti-Stokes and Coherent Stokes in Raman Scattering by Superconducting Nanowire Single-Photon Detector for Temperature Measurement

Directory of Open Access Journals (Sweden)

Annepu Venkata Naga Vamsi

2016-01-01

Full Text Available We have reported the measurement of temperature by using coherent anti-Stroke and coherent Stroke Raman scattering using superconducting nano wire single-photon detector. The measured temperatures by both methods (Coherent Anti-Raman scattering & Coherent Stroke Raman scattering and TC 340 are in good accuracy of ± 5 K temperature range. The length of the pipe line under test can be increased by increasing the power of the pump laser. This methodology can be widely used to measure temperatures at instantaneous positions in test pipe line or the entire temperature of the pipe line under test.

Fast temperature programming in gas chromatography using resistive heating

NARCIS (Netherlands)

Dallüge, J.; Ou-Aissa, R.; Vreuls, J.J.; Brinkman, U.A.T.; Veraart, J.R.

1999-01-01

The features of a resistive-heated capillary column for fast temperature-programmed gas chromatography (GC) have been evaluated. Experiments were carried out using a commercial available EZ Flash GC, an assembly which can be used to upgrade existing gas chromatographs. The capillary column is placed

High resolution silicon detectors for colliding beam physics

International Nuclear Information System (INIS)

Amendolia, S.R.; Bedeschi, F.; Bertolucci, E.; Bettoni, D.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Dell'Orso, M.; Fidecaro, F.; Foa, L.; Focardi, E.; Giannetti, P.; Giorgi, M.A.; Marrocchesi, P.S.; Menzione, A.; Raso, G.; Ristori, L.; Scribano, A.; Stefanini, A.; Tenchini, R.; Tonelli, G.; Triggiani, G.

1984-01-01

Resolution and linearity of the position measurement of Pisa multi-electrode silicon detectors are presented. The detectors are operated in slightly underdepleted mode and take advantage of their intrinsic resistivity for resistive charge partition between adjacent strips. 22 μm resolution is achieved with readout lines spaced 300 μm. Possible applications in colliding beam experiments for the detection of secondary vertices are discussed. (orig.)

Characterization procedures for double-sided silicon microstrip detectors

Energy Technology Data Exchange (ETDEWEB)

Bruner, N.L. [New Mexico Univ., Albuquerque, NM (United States). New Mexico Center for Particle Phys.; Frautschi, M.A. [New Mexico Univ., Albuquerque, NM (United States). New Mexico Center for Particle Phys.; Hoeferkamp, M.R. [New Mexico Univ., Albuquerque, NM (United States). New Mexico Center for Particle Phys.; Seidel, S.C. [New Mexico Univ., Albuquerque, NM (United States). New Mexico Center for Particle Phys.

1995-08-15

Since double-sided silicon microstrip detectors are still evolving technologically and are not yet commercially available, they require extensive electrical evaluation by the user to ensure they were manufactured to specifications. In addition, measurements must be performed to determine detector operating conditions. Procedures for measuring the following quantities are described: - Leakage current, - Depletion voltage, - Bias resistance, - Interstrip resistance, - Coupling capacitance, - Coupling capacitor breakdown voltage. (orig.).

Characterization procedures for double-sided silicon microstrip detectors

International Nuclear Information System (INIS)

Bruner, N.L.; Frautschi, M.A.; Hoeferkamp, M.R.; Seidel, S.C.

1995-01-01

Since double-sided silicon microstrip detectors are still evolving technologically and are not yet commercially available, they require extensive electrical evaluation by the user to ensure they were manufactured to specifications. In addition, measurements must be performed to determine detector operating conditions. Procedures for measuring the following quantities are described: - Leakage current, - Depletion voltage, - Bias resistance, - Interstrip resistance, - Coupling capacitance, - Coupling capacitor breakdown voltage. (orig.)

Pressure and temperature induced electrical resistance change in nano-carbon/epoxy composites

NARCIS (Netherlands)

Shen, J. T.; Buschhorn, S. T.; De Hosson, J. Th. M.; Schulte, K.; Fiedler, B.

2015-01-01

In this study, we investigate the changes of electrical resistance of the carbon black (CB) and carbon nanotube (CNT) filled epoxy composites upon compression, swelling and temperature variation. For all samples we observe a decrease of electrical resistance under compression, while an increase of

The Effect of Temperature and Host Plant Resistance on Population Growth of the Soybean Aphid Biotype 1 (Hemiptera: Aphididae).

Science.gov (United States)

Hough, Ashley R; Nechols, James R; McCornack, Brian P; Margolies, David C; Sandercock, Brett K; Yan, Donglin; Murray, Leigh

2017-02-01

A laboratory experiment was conducted to evaluate direct and indirect effects of temperature on demographic traits and population growth of biotype 1 of the soybean aphid, Aphis glycines Matsumura. Our objectives were to better understand how temperature influences the expression of host plant resistance, quantify the individual and interactive effects of plant resistance and temperature on soybean aphid population growth, and generate thermal constants for predicting temperature-dependent development on both susceptible and resistant soybeans. To assess indirect (plant-mediated) effects, soybean aphids were reared under a range of temperatures (15-30 °C) on soybean seedlings from a line expressing a Rag1 gene for resistance, and life history traits were quantified and compared to those obtained for soybean aphids on a susceptible soybean line. Direct effects of temperature were obtained by comparing relative differences in the magnitude of life-history traits among temperatures on susceptible soybeans. We predicted that temperature and host plant resistance would have a combined, but asymmetrical, effect on soybean aphid fitness and population growth. Results showed that temperature and plant resistance influenced preimaginal development and survival, progeny produced, and adult longevity. There also appeared to be a complex interaction between temperature and plant resistance for survival and developmental rate. Evidence suggested that the level of plant resistance increased at higher, but not lower, temperature. Soybean aphids required about the same number of degree-days to develop on resistant and susceptible plants. Our results will be useful for making predictions of soybean aphid population growth on resistant plants under different seasonal temperatures. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Low-temperature resistivity anomaly in underdoped Pr0.8Sr0.2MnO3 manganite nanoparticles

International Nuclear Information System (INIS)

Das, Proloy T.; Giri, S.K.; Panda, J.; Taraphder, A.; Nath, T.K.; Nigam, A.K.

2013-01-01

High resolution electrical resistivity measurements were carried out of under-doped Pr 0.8 Sr 0.2 MnO 3 manganite nanoparticles with grain size modulation down to 40 nm in magnetic fields H, from 0 to 9 T in the low temperature regime down to a temperature of 4.2 K. In the temperature range below 80 K, a distinct resistivity minima is observed for all the samples with different particle sizes for all H. While trying to fit low temperature resistivity data with different models for the observed resistivity minima with negative temperature coefficient of resistance (TCR) for all H, it appears that all the data for different particle sizes, can be best described by electron-electron (e-e) interaction effect in comparison with other models, e.g., Kondo model, coulomb blockades etc. The low temperature data for all H have been fitted with an expression containing three terms, namely, residual resistivity, inelastic scattering, e-e interaction and Kondo effects. We conclude that the e-e interaction is the dominant transport mechanism at low temperatures for the observed negative TCR in this strongly disordered nanometric Pr 0.8 Sr 0.2 MnO 3 phase separated manganite system. (author)

Laser beam joining of non-oxidic ceramics for ultra high temperature resistant joints

International Nuclear Information System (INIS)

Lippmann, W.; Knorr, J.; Wolf, R.; Reinecke, A.M.; Rasper, R.

2004-01-01

The excellent technical properties of silicon carbide (SiC) and silicon nitride (Si 3 N 4 ) ceramics, such as resistance to extreme temperatures, oxidation, mechanical wear, aggressive chemical substances and radioactive radiation and also its high thermal conductivity and good temperature-shock resistance, make these ceramics ideally suited for use in the field of nuclear technology. However, their practical use has been limited so far because of the unavailability of effective joining techniques for these ceramics, especially for high temperature applications. A new joining technology (CERALINK registered ) has been developed in a network project which allowed high temperature resistant and vacuum-tight joining of SiC or Si 3 N 4 ceramics. A power laser is used as heat source, which makes it possible to join ceramic components in free atmosphere in combination with a pure oxidic braze filler. As no furnace is necessary, there are no limitations on the component dimensions by the furnace-geometry. During the joining process, the heated area can be limited to the seam area so that this technology can also be used to encapsulate materials with a low melting point. The seam has a high mechanical strength, it is resistant to a wide range of chemicals and radiation and it is also vacuum-tight. The temperature resistance can be varied by variation of the braze filler composition - usually between 1,400 C and >1,600 C. Beside the optimum filler it is also important to select the suitable laser wavelength. The paper will demonstrate the influence of different wave lengths, i. e. various laser types, on the seam quality. Examples are chosen to illustrate the strengths and limitations of the new technology

The High-Temperature Resistance Properties of Polysiloxane/Al Coatings with Low Infrared Emissivity

Directory of Open Access Journals (Sweden)

Jun Zhao

2018-03-01

Full Text Available High-temperature-resistant coatings with low infrared emissivity were prepared using polysiloxane resin and flake aluminum as the adhesive and pigment, respectively. The heat resistance mechanisms of the polysiloxane/Al coating were systematically investigated. The composition, surface morphology, infrared reflectance spectra, and thermal expansion dimension (ΔL of the coatings were characterized by X-ray photoelectron spectroscopy (XPS, field emission scanning electron microscopy (FE-SEM, Fourier transform infrared spectroscopy, and thermal mechanical analysis (TMA, respectively. The results show that thermal decomposition of the resin and mismatch of ΔL between the coating and the substrate facilitate the high temperature failure of the coating. A suitable amount of flake aluminum pigments could restrain the thermal decomposition of the resin and could increase the match degree of ΔL between the coating and substrate, leading to an enhanced thermal resistance of the coating. Our results find that a coating with a pigment to binder ratio (P/B ratio of 1.0 could maintain integrity until 600 °C, and the infrared emissivity was as low as 0.27. Hence, a coating with high-temperature resistance and low emissivity was obtained. Such coatings can be used for infrared stealth technology or energy savings in high-temperature equipment.

Design and characterization of radiation resistant integrated circuits for the LHC particle detectors using deep sub-micron CMOS technologies

International Nuclear Information System (INIS)

Anelli, Giovanni Maria

2000-01-01

The electronic circuits associated with the particle detectors of the CERN Large Hadron Collider (LHC) have to work in a highly radioactive environment. This work proposes a methodology allowing the design of radiation resistant integrated circuits using the commercial sub-micron CMOS technology. This method uses the intrinsic radiation resistance of ultra-thin grid oxides, the technology of enclosed layout transistors (ELT), and the protection rings to avoid the radio-induced creation of leakage currents. In order to check the radiation tolerance level, several test structures have been designed and tested with different radiation sources. These tests have permitted to study the physical phenomena responsible for the damages induced by the radiations and the possible remedies. Then, the particular characteristics of ELT transistors and their influence on the design of complex integrated circuits has been explored. The modeling of the W/L ratio, the asymmetries (for instance in the output conductance) and the performance of ELT couplings have never been studied yet. The noise performance of the 0.25 μ CMOS technology, used in the design of several integrated circuits of the LHC detectors, has been characterized before and after irradiation. Finally, two integrated circuits designed using the proposed method are presented. The first one is an analogic memory and the other is a circuit used for the reading of the signals of one of the LHC detectors. Both circuits were irradiated and have endured very high doses practically without any sign of performance degradation. (J.S.)

Evaluation of prototype silicon drift detectors

International Nuclear Information System (INIS)

Ellison, J.; Hall, G.; Roe, S.; Lucas, A.

1988-01-01

Operating characteristics of several prototypes of silicon drift detectors are investigated. Detectors are made of unpolished silicon produced by the zone melting method and characterized by n-type conductivity and specific resistance of 3.6-4.6 kOhmxcm. The detectors comprise 40 parallel bands of 200 μm width and 1 cm length separated by 50 μm intervals. Data characterizing the potential distribution near anodes under the operating bias voltage, dependences of capacities and leakage as well as the detector space resolution

Germanium nitride and oxynitride films for surface passivation of Ge radiation detectors

Energy Technology Data Exchange (ETDEWEB)

Maggioni, G., E-mail: maggioni@lnl.infn.it [Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, Via Marzolo 8, I-35131 Padova (Italy); Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell’Universita’2, I-35020 Legnaro, Padova (Italy); Carturan, S. [Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, Via Marzolo 8, I-35131 Padova (Italy); Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell’Universita’2, I-35020 Legnaro, Padova (Italy); Fiorese, L. [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell’Universita’2, I-35020 Legnaro, Padova (Italy); Dipartimento di Ingegneria dei Materiali e delle Tecnologie Industriali, Università di Trento, Via Mesiano 77, I-38050 Povo, Trento (Italy); Pinto, N.; Caproli, F. [Scuola di Scienze e Tecnologie, Sezione di Fisica, Università di Camerino, Via Madonna delle Carceri 9, Camerino (Italy); INFN, Sezione di Perugia, Perugia (Italy); Napoli, D.R. [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell’Universita’2, I-35020 Legnaro, Padova (Italy); Giarola, M.; Mariotto, G. [Dipartimento di Informatica—Università di Verona, Strada le Grazie 15, I-37134 Verona (Italy)

2017-01-30

Highlights: • A surface passivation method for HPGe radiation detectors is proposed. • Highly insulating GeNx- and GeOxNy-based layers are deposited at room temperature. • Deposition parameters affect composition and electrical properties of the layers. • The improved performance of a GeNx-coated HPGe diode is assessed. - Abstract: This work reports a detailed investigation of the properties of germanium nitride and oxynitride films to be applied as passivation layers to Ge radiation detectors. All the samples were deposited at room temperature by reactive RF magnetron sputtering. A strong correlation was found between the deposition parameters, such as deposition rate, substrate bias and atmosphere composition, and the oxygen and nitrogen content in the film matrix. We found that all the films were very poorly crystallized, consisting of very small Ge nitride and oxynitride nanocrystallites, and electrically insulating, with the resistivity changing from three to six orders of magnitude as a function of temperature. A preliminary test of these films as passivation layers was successfully performed by depositing a germanium nitride film on the intrinsic surface of a high-purity germanium (HPGe) diode and measuring the improved performance, in terms of leakage current, with respect to a reference passivated diode. All these interesting results allow us to envisage the application of this coating technology to the surface passivation of germanium-based radiation detectors.

Noise and optimum filtering in spectrometers with semiconductor detectors operating at elevated temperature

International Nuclear Information System (INIS)

Dabrowski, W.; Korbel, K.

1983-01-01

The importance of the excess noise in the semiconductor detectors operating at the elevated temperature is discussed. Under the assumption of a conventional CR-RC type filtration the variancy of the noise output is determined. The new term ''second noise-corner time constant'' was proposed. The expression for relative signal-to-noise ratio as the dependence on the noise as well as circuits time constants was derived. It was also presented in a graphical form. 12 refs., 6 figs. (author)

The effect of cathode bias (field effect) on the surface leakage current of CdZnTe detectors

International Nuclear Information System (INIS)

Bolotnikov, A.E.; Hubert Chen, C.M.; Cook, W.R.; Harrison, F.A.; Kuvvetli, I.; Schindler, S.M.; Stahle, C.M.; Parker, B.H.

2003-01-01

Surface resistivity is an important parameter of multi-electrode CZT detectors such as coplanar-grid, strip, or pixel detectors. Low surface resistivity results in a high leakage current and affects the charge collection efficiency in the areas near contacts. Thus, it is always desirable to have the surface resistivity of the detector as high as possible. In the past the most significant efforts were concentrated to develop passivation techniques for CZT detectors. However, as we found, the field-effect caused by a bias applied on the cathode can significantly reduce the surface resistivity even though the detector surface was carefully passivated. In this paper we illustrate that the field-effect is a common feature of the CZT multi-electrode detectors, and discuss how to take advantage of this effect to improve the surface resistivity of CZT detectors

A portable borehole temperature logging system using the four-wire resistance method

Science.gov (United States)

Erkan, Kamil; Akkoyunlu, Bülent; Balkan, Elif; Tayanç, Mete

2017-12-01

High-quality temperature-depth information from boreholes with a depth of 100 m or more is used in geothermal studies and in studies of climate change. Electrical wireline tools with thermistor sensors are capable of measuring borehole temperatures with millikelvin resolution. The use of a surface readout mode allows analysis of the thermally conductive state of a borehole, which is especially important for climatic and regional heat flow studies. In this study we describe the design of a portable temperature logging tool that uses the four-wire resistance measurement method. The four-wire method enables the elimination of cable resistance effects, thus allowing millikelvin resolution of temperature data at depth. A preliminary two-wire model of the system is also described. The portability of the tool enables one to collect data from boreholes down to 300 m, even in locations with limited accessibility.

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

RNA-Seq analysis reveals insight into enhanced rice Xa7-mediated bacterial blight resistance at high temperature.

Directory of Open Access Journals (Sweden)

Stephen P Cohen

Full Text Available Plant disease is a major challenge to agriculture worldwide, and it is exacerbated by abiotic environmental factors. During some plant-pathogen interactions, heat stress allows pathogens to overcome host resistance, a phenomenon which could severely impact crop productivity considering the global warming trends associated with climate change. Despite the importance of this phenomenon, little is known about the underlying molecular mechanisms. To better understand host plant responses during simultaneous heat and pathogen stress, we conducted a transcriptomics experiment for rice plants (cultivar IRBB61 containing Xa7, a bacterial blight disease resistance (R gene, that were infected with Xanthomonas oryzae, the bacterial blight pathogen of rice, during high temperature stress. Xa7-mediated resistance is unusual relative to resistance mediated by other R genes in that it functions better at high temperatures. Using RNA-Seq technology, we identified 8,499 differentially expressed genes as temperature responsive in rice cultivar IRBB61 experiencing susceptible and resistant interactions across three time points. Notably, genes in the plant hormone abscisic acid biosynthesis and response pathways were up-regulated by high temperature in both mock-treated plants and plants experiencing a susceptible interaction and were suppressed by high temperature in plants exhibiting Xa7-mediated resistance. Genes responsive to salicylic acid, an important plant hormone for disease resistance, were down-regulated by high temperature during both the susceptible and resistant interactions, suggesting that enhanced Xa7-mediated resistance at high temperature is not dependent on salicylic acid signaling. A DNA sequence motif similar to known abscisic acid-responsive cis-regulatory elements was identified in the promoter region upstream of genes up-regulated in susceptible but down-regulated in resistant interactions. The results of our study suggest that the plant

Effect of temperature on structure and corrosion resistance for ...

Indian Academy of Sciences (India)

The effect of plating temperatures between 60 and 90◦C on structure and corrosion resistance for elec- troless NiWP coatings ..... which helps to form fine grain. At 80 .... [23] Zhang W X, Jiang Z H, Li G Y and Jiang Q 2008 Surf. Coat. Technol.

Correlation of Critical Temperatures and Electrical Properties in Titanium Films

Science.gov (United States)

Gandini, C.; Lacquaniti, V.; Monticone, E.; Portesi, C.; Rajteri, M.; Rastello, M. L.; Pasca, E.; Ventura, G.

Recently transition-edge sensors (TES) have obtained an increasing interest as light detectors due to their high energy resolution and broadband response. Titanium (Ti), with transition temperature up to 0.5 K, is among the suitable materials for TES application. In this work we investigate Ti films obtained from two materials of different purity deposited by e-gun on silicon nitride. Films with different thickness and deposition substrate temperature have been measured. Critical temperatures, electrical resistivities and structural properties obtained from x-ray are related to each other.

Numerical simulation of temperature's sensitivity of chamfer hole's resistance on hydraulic step cylinder

International Nuclear Information System (INIS)

Jinhua, Wang; Hanliang, Bo; Wenxiang, Zheng; Jinnong, Yang

2003-01-01

The control rod drive is a very important device for controlling nuclear reactor startup, operation, shut down, and power change. The ability of the control rod drive to move safely and reliably directly relates to reactor safety. The Hydraulic Control Rod Drive System (HCRDS) is a new type of control rod drive system developed by the Institute of Nuclear Energy Technology (INET) of Tsinghua University for Nuclear Heating Reactors. The HCRDS, designed using the hydrodynamic principle, has many advantages, including having the structure complete in the vessel, no possible ejection accident, short drive line, simple movable parts structure and safe shutdown during accidents. The hydraulic step cylinder is the key part for the HCRDS. In the process of reactor startup, the variation of temperature could make the water's density and viscosity change, and the force from the water flow would change accordingly. These factors could influence the performance of the hydraulic step cylinder. In this paper, the temperature sensitivity of the chamfer hole's resistance in the hydraulic step cylinder was studied with the Computational Fluid Dynamics (CFD) program CFX5.5. The results were satisfactory: the discipline of variation of the chamfer hole's resistance with the outer tube's position was the same at different temperatures, the discrepancy of the chamfer hole's resistance was small for the same position at different temperatures, the chamfer hole's resistance decreased gradually with the increase of temperature, and the decrease extent was relatively small

Development of leak detection system using high temperature-resistant microphones

International Nuclear Information System (INIS)

Morishita, Yoshitsugu; Mochizuki, Hiroyasu; Watanabe, Kenshiu; Nakamura, Takahisa; Nakazima, Yoshiaki; Yamauchi, Tatsuya

1995-01-01

This report describes the development and testing of a coolant leak detection system for an inlet feeder pipe of an advanced thermal reactor (ATR) using high temperature-resistant microphones. Such microphones must be resistant to both high temperatures and high radiation doses. Leakage sound characteristics, attenuation of the sound level in a heat insulating box for the inlet feeder pipes, and background noise were investigated using the experimental facility and the prototype ATR 'FUGEN'. The optimum frequency ranges for the microphone were then determined based on the observed leakage sound and background noise. The ability of the microphone to discriminate between leaks and other burst-type noises was also investigated by statistical analyses. Finally, it was confirmed that the present method could detect a leak within a couple of seconds. (author)

Post-growth annealing of Bridgman-grown CdZnTe and CdMnTe crystals for room-temperature nuclear radiation detectors

International Nuclear Information System (INIS)

Egarievwe, Stephen U.; Yang, Ge; Egarievwe, Alexander A.; Okwechime, Ifechukwude O.; Gray, Justin; Hales, Zaveon M.; Hossain, Anwar; Camarda, Giuseppe S.; Bolotnikov, Aleksey E.; James, Ralph B.

2015-01-01

Bridgman-grown cadmium zinc telluride (CdZnTe or CZT) and cadmium manganese telluride (CdMnTe or CMT) crystals often have Te inclusions that limit their performances as X-ray- and gamma-ray-detectors. We present here the results of post-growth thermal annealing aimed at reducing and eliminating Te inclusions in them. In a 2D analysis, we observed that the sizes of the Te inclusions declined to 92% during a 60-h annealing of CZT at 510 °C under Cd vapor. Further, tellurium inclusions were eliminated completely in CMT samples annealed at 570 °C in Cd vapor for 26 h, whilst their electrical resistivity fell by an order of 10 2 . During the temperature-gradient annealing of CMT at 730 °C and an 18 °C/cm temperature gradient for 18 h in a vacuum of 10 −5 mbar, we observed the diffusion of Te from the sample, so causing a reduction in size of the Te inclusions. For CZT samples annealed at 700 °C in a 10 °C/cm temperature gradient, we observed the migration of Te inclusions from a low-temperature region to a high one at 0.022 μm/s. During the temperature-gradient annealing of CZT in a vacuum of 10 −5 mbar at 570 °C and 30 °C/cm for 18 h, some Te inclusions moved toward the high-temperature side of the wafer, while other inclusions of the same size, i.e., 10 µm in diameter, remained in the same position. These results show that the migration, diffusion, and reaction of Te with Cd in the matrix of CZT- and CMT-wafers are complex phenomena that depend on the conditions in local regions, such as composition and structure, as well as on the annealing conditions

Responses and mechanisms of positive electron affinity molecules in the N2 mode of the thermionic ionization detector and the electron-capture detector

International Nuclear Information System (INIS)

Jones, C.S.

1989-01-01

Very little knowledge has been acquired in the past on the mechanistic pathway by which molecules respond in the N 2 mode of the thermionic ionization detector. An attempt is made here to elucidate the response mechanism of the detector. The basic response mechanisms are known for the electron capture detector, and an attempt is made to identify the certain mechanism by which selected molecules respond. The resonance electron capture rate constant has been believed to be temperature independent, and investigations of the temperature dependence of electron capture responses are presented. Mechanisms for the N 2 mode of the thermionic ionization detector have been proposed by examining the detector response to positive electron affinity molecules and by measurement of the ions produced by the detector. Electron capture mechanisms for selected molecules have been proposed by examining their temperature dependent responses in the electron capture detector and negative ion mass spectra of the samples. In studies of the resonance electron capture rate constant, the relative responses of selected positive electron affinity molecules and their temperature dependent responses were investigated. Positive electron affinity did not guarantee large responses in the N 2 mode thermionic ionization detector. High mass ions were measured following ionization of samples in the detector. Responses in the electron capture detector varied with temperature and electron affinity

Small area silicon diffused junction x-ray detectors

International Nuclear Information System (INIS)

Walton, J.T.; Pehl, R.H.; Larsh, A.E.

1981-10-01

The low temperature performance of silicon diffused junction detectors in the measurement of low energy x-rays is reported. The detectors have an area of 0.04 cm 2 and a thickness of 100 μm. The spectral resolutions of these detectors were found to be in close agreement with expected values indicating that the defects introduced by the high temperature processing required in the device fabrication were not deleteriously affecting the detection of low energy x-rays. Device performance over a temperature range of 77 to 150 0 K is given. These detectors were designed to detect low energy x-rays in the presence of minimum ionizing electrons. The successful application of silicon diffused junction technology to x-ray detector fabrication may facilitate the development of other novel silicon x-ray detector designs

Small area silicon diffused junction X-ray detectors

Science.gov (United States)

Walton, J. T.; Pehl, R. H.; Larsh, A. E.

1982-01-01

The low-temperature performance of silicon diffused junction detectors in the measurement of low energy X-rays is reported. The detectors have an area of 0.04 sq cm and a thickness of 100 microns. The spectral resolutions of these detectors were found to be in close agreement with expected values, indicating that the defects introduced by the high-temperature processing required in the device fabrication were not deleteriously affecting the detection of low-energy X-rays. Device performance over a temperature range of 77 K to 150 K is given. These detectors were designed to detect low-energy X-rays in the presence of minimum ionizing electrons. The successful application of silicon-diffused junction technology to X-ray detector fabrication may facilitate the development of other novel silicon X-ray detector designs.

A study on the improvement of oxidation resistance of OAE-added stainless steels for high temperature applications

International Nuclear Information System (INIS)

Kim, Dae Hwan; Kim, Gil Moo

1996-01-01

Since the manufacturing temperature of stainless steels is relatively high, oxidation at the elevated temperature becomes important. The chemical and physical properties of the protective oxide film which was formed on the stainless steels at high temperature for the oxidation resistance are important in determining the rate of oxidation and the life of equipment exposed to high temperature oxidizing environments. In this study, the oxidation behavior of STS 309S and STS 409L added by a small amount of oxygen active element(each + 0.5wt% Hf and Y) was studied to improve oxidation resistance. In the cyclic oxidation, while OAE-free specimens showed relatively poor oxidation resistance due to spallations and cracks of Cr-rich oxide layer, OAE-added specimens improved cyclic oxidation resistance assumably due to constant oxidation rate with stable oxide layers at high temperature. Especially Hf improved cyclic oxidation resistance by forming Cr-rich oxide layer preventing internal oxidation in STS 309S. (author)

Elsevier R&D on a new type of micropattern gaseous detector: The Fast Timing Micropattern detector

CERN Document Server

Abbaneo, D; Abbrescia, M; Abi Akl, M; Aboamer, O; Acosta, D; Ahmad, A; Ahmed, W; Aleksandrov, A; Altieri, P; Asawatangtrakuldee, C; Aspell, P; Assran, Y; Awan, I; Bally, S; Ban, Y; Banerjee, S; Barashko, V; Barria, P; Bencze, G; Beni, N; Benussi, L; Bhopatkar, V; Bianco, S; Bos, J; Bouhali, O; Braghieri, A; Braibant, S; Buontempo, S; Calabria, C; Caponero, M; Caputo, C; Cassese, F; Castaneda, A; Cauwenbergh, S; Cavallo, F R; Celik, A; Choi, M; Choi, S; Christiansen, J; Cimmino, A; Colafranceschi, S; Colaleo, A; Conde Garcia, A; Czellar, S; Dabrowski, M M; De Lentdecker, G; Oliveira, R De; De Robertis, G; Dildick, S; Dorney, B; Endroczi, G; Errico, F; Fallavollita, F; Fenyvesi, A; Ferry, S; Furic, I; Giacomelli, P; Gilmore, J; Golovtsov, V; Guiducci, L; Guilloux, F; Gutierrez, A; Hadjiiska, R M; Hauser, J; Hoepfner, K; Hohlmann, M; Hoorani, H; Iaydjiev, P; Jeng, Y G; Kamon, T; Karchin, P; Korytov, A; Krutelyov, S; Kumar, A; Kim, H; Lee, J; Lenzi, T; Litov, L; Loddo, F; Madorsky, A; Maerschalk, T; Maggi, M; Magnani, A; Mal, P K; Mandal, K; Marchioro, A; Marinov, A; Majumdar, N; Merlin, J A; Mitselmakher, G; Mohanty, A K; Mohapatra, A; Molnar, J; Muhammad, S; Mukhopadhyay, S; Naimuddin, M; Nuzzo, S; Oliveri, E; Pant, L M; Paolucci, P; Park, I; Passeggio, G; Pavlov, B; Philipps, B; Piccolo, D; Postema, H; Puig Baranac, A; Radi, A; Radogna, R; Raffone, G; Ranieri, A; Rashevski, G; Ressegotti, M; Riccardi, C; Rodozov, M; Rodrigues, A; Ropelewski, L; RoyChowdhury, S; Ryu, G; Ryu, M S; Safonov, A; Salva, S; Saviano, G; Sharma, A; Sharma, A; Sharma, R; Shah, A H; Shopova, M; Sturdy, J; Sultanov, G; Swain, S K; Szillasi, Z; Talvitie, J; Tatarinov, A; Tuuva, T; Tytgat, M; Vai, I; Van Stenis, M; Venditti, R; Verhagen, E; Verwilligen, P; Vitulo, P; Volkov, S; Vorobyev, A; Wang, D; Wang, M; Yang, U; Yang, Y; Yonamine, R; Zaganidis, N; Zenoni, F; Zhang, A

2017-01-01

Micropattern gaseous detectors (MPGD) underwent significant upgrades in recent years, introducing resistive materials to build compact spark-protected devices. Exploiting this technology further, various features such as space and time resolution, rate capability, sensitive area, operational stability and radiation hardness can be improved. This contribution introduces a new type of MPGD, namely the Fast Timing Micropattern (FTM) detector, utilizing a fully resistive WELL structure. It consists of a stack of several coupled layers where drift and WELL multiplication stages alternate in the structure, yielding a significant improvement in timing properties due to competing ionization processes in the different drift regions. Two FTM prototypes have been developed so far. The first one is uWELL-like, where multiplication takes place in the holes of a kapton foil covered on both sides with resistive material. The second one has a resistive Micromegas-like structure, with multiplication developing in a region del...

Neutron detector with monitoring elements

International Nuclear Information System (INIS)

Haller, P.

1976-01-01

To check the reliable reading of a neutron detector the signal of which results from (n,e) processes and which is used for neutron flux supervision in the reactor core of pressurized-water reactors, a circuit is given which makes it possible to record the isolation resistivity of the cable connected to the input of the current amplifier and of the neutron detector, this resistivity determining, among others, the output signal. For supervision, the input offset voltage of the current amplifier is modulated by a low-frequency ac voltage and a filter is assigned to the output of an op amplifier, this filter feeding a limiting value recorder. (ORU) [de

Studies of double-sided silicon microstrip detectors

Energy Technology Data Exchange (ETDEWEB)

Seidel, S.C. [New Mexico Univ., Albuquerque, NM (United States). Center for Particle Phys.; Bruner, N.L. [New Mexico Univ., Albuquerque, NM (United States). Center for Particle Phys.; Frautschi, M.A. [New Mexico Univ., Albuquerque, NM (United States). Center for Particle Phys.; Hoeferkamp, M.R. [New Mexico Univ., Albuquerque, NM (United States). Center for Particle Phys.; Patton, A. [New Mexico Univ., Albuquerque, NM (United States). Center for Particle Phys.

1996-12-01

The electrical characteristics of detectors manufactured by SINTEF/SI with a variety of geometrical and processing options have been investigated. The detectors` leakage current, depletion voltage, bias resistance, interstrip and coupling capacitance, and coupling capacitor breakdown voltage were studied. (orig.).

Studies of double-sided silicon microstrip detectors

International Nuclear Information System (INIS)

Seidel, S.C.; Bruner, N.L.; Frautschi, M.A.; Hoeferkamp, M.R.; Patton, A.

1996-01-01

The electrical characteristics of detectors manufactured by SINTEF/SI with a variety of geometrical and processing options have been investigated. The detectors' leakage current, depletion voltage, bias resistance, interstrip and coupling capacitance, and coupling capacitor breakdown voltage were studied. (orig.)

Subnanosecond timing with ion-implanted detectors

International Nuclear Information System (INIS)

Rijken, H.A.; Klein, S.S.; Jacobs, W.; Teeuwen, L.J.H.G.W.; Voigt, M.J.A. de; Burger, P.

1992-01-01

The energy resolution of ion-implanted charged particle detectors may be improved by decreasing the thickness of the implanted detector window to minimize energy straggling. Because of the resistance of this layer, however, the timing depends on the position of entry. Two solutions to this conflict between energy resolution and time resolution are studied: evaporating a very thin aluminum layer on the detector window and fabricating a rectangular detector. Both solutions are shown to be successful with a total time resolution in the low subnanosecond region (<200 ps). (orig.)

Long duration performance of high temperature irradiation resistant thermocouples

International Nuclear Information System (INIS)

Rempe, J.; Knudson, D.; Condie, K.; Cole, J.; Wilkins, S.C.

2007-01-01

Many advanced nuclear reactor designs require new fuel, cladding, and structural materials. Data are needed to characterize the performance of these new materials in high temperature, radiation conditions. However, traditional methods for measuring temperature in-pile degrade at temperatures above 1100 C degrees. To address this instrumentation need, the Idaho National Laboratory (INL) developed and evaluated the performance of a high temperature irradiation-resistant thermocouple that contains alloys of molybdenum and niobium. To verify the performance of INL's recommended thermocouple design, a series of high temperature (from 1200 to 1800 C) long duration (up to six months) tests has been initiated. This paper summarizes results from the tests that have been completed. Data are presented from 4000 hour tests conducted at 1200 and 1400 C that demonstrate the stability of this thermocouple (less than 2% drift). In addition, post test metallographic examinations are discussed which confirm the compatibility of thermocouple materials throughout these long duration, high temperature tests. (authors)

Fracture resistance of asphalt concrete modified with crumb rubber at low temperatures

Directory of Open Access Journals (Sweden)

A. Razmi

2018-05-01

Full Text Available The main objective of this study is to obtain fracture toughness of asphalt concrete modified by Crumb Rubber (CR and Sasobit at low temperatures. First, Bending Beam Rheometer (BBR test was performed on unmodified binder (binder 60/70, binder 60/70 + 3%Sasobit and 20%CR + 3%Sasobit modified asphalt binder to find how each modifier affect asphalt binder stiffness and relaxation rate at low temperatures. Mixed mode I/II fracture tests were conducted by cracked Semi-Circular Bending (SCB specimens and the critical stress intensity factors were calculated for pure mode I, mixed mode I/II and pure mode II conditions. Results of BBR tests indicated that 20%CR + 3%Sasobit reduces stiffness and the m-value increase at low temperatures. As a result, 20%CR + 3%Sasobit has positive effect on low temperatures performance by improving thermal cracking resistance. Also, according to the fracture toughness test results, the Warm Mix Asphalt (WMA mixture containing 20% CR, shows higher resistance against crack growth than WMA mixture. It was found that mixed mode I/II can be more detrimental than pure mode I and II conditions. Keywords: Crumb rubber, Asphalt concrete, Bending Beam Rheometer, Fracture resistance, Semi-circular bending test

Micro controller based design of digital transmitters for temperature measurements in reactors

International Nuclear Information System (INIS)

Nassar, M.A.M.

2011-01-01

Temperature transmitter is one of the most important transmitters in the nuclear reactor it is used for RTD (resistance temperature detector) signal conditioning. It has built-in current excitation, instrumentation amplifier, linearization and current output circuitry which amplifies the RTD signal and gives linearization to it. It is a part of a system to get temperature and monitoring it. This system is very cost and complicated. In this work a digital system is implemented by using micro controller techniques that replaces the existing system, one chip (PIC16f877) is used to build a digital system, which is more accurate and give more performance and low costs . RTD is the sensing element of temperature, its resistance increases with temperature. There are many types of transmitters in the reactor such as temperature, pressure, level and flow but temperature one is chosen because of temperature is one of the most important parameters in process control.

Effect of Contact Pressure on the Resistance Contact Value and Temperature Changes in Copper Busbar Connection

Directory of Open Access Journals (Sweden)

Agus Risdiyanto

2012-12-01

Full Text Available This paper discussed the influence of tightness or contacts pressure on copper busbar joints to determine changes in the value of the initial contact resistance and the maximum temperature at the joint due to high current load. The test sample was copper busbar 3 x 30 mm with configuration of bolted overlapping joint. Increasing contact pressure at the joint was measured to find out its effect on the value of contact resistance. The applied pressure was 6 to 36 MPa. Procedure of contact resistance measurement refer to the ASTM B539 standard using four-wire method. The sample subsequently loaded with the current of 350 A for 60 minutes and the maximum temperature at the joint was measured. The result showed that increasing contact pressure at the busbar joint will reduce the contact resistance and maximum temperature. The increase of contact pressure from 6 to 30 MPa causes decreasing contact resistance from 16 μΩ to 11 μΩ. Further increasing of contact pressure more than 30 MPa did not affect the contact resistance significantly. The lowest temperatur of busbar joint of 54°C was reached at a contact pressure of 36 Mpa.

Effect of temperature on the multi-gap resistive plate chamber operation

International Nuclear Information System (INIS)

Zhao, Y.E.; Wang, X.L.; Liu, H.D.; Chen, H.F.; Li, C.; Wu, J.; Xu, Z.Z.; Shao, M.; Zeng, H.; Zhou, Y.

2005-01-01

In order to obtain a quantitative understanding of the influence of temperature on the multi-gap resistive plate chamber (MRPC) operation, we tested the performance of a 6-gap, 6.1x20 cm 2 active area MRPC with cosmic rays at different temperatures. Results of measurements of noise rate, dark current and detection efficiency are presented

Performance of room temperature mercuric iodide (HgI2) detectors in the ultra low energy x-ray region

International Nuclear Information System (INIS)

Dabrowski, A.J.; Iwanczyk, J.S.; Barton, J.B.; Huth, G.C.; Whited, R.; Ortale, C.; Economou, T.E.; Turkevich, A.L.

1980-01-01

Performance of room temperature mercuric iodide x-ray spectrometers has been recently improved through new fabrication techniques and further development of low noise associated electronic systems. This progress has extended the range of measurements to the ultra low energy x-ray region at room temperature. This paper reports the study of the effect of contact material on the performance of HgI 2 detectors in the low energy x-ray region

Aluminide protective coatings on high–temperature creep resistant cast steel

Directory of Open Access Journals (Sweden)

J. Kubicki

2009-10-01

Full Text Available This paper presents the results of research on aluminide protective coatings manufactured on high–temperature creep resistant cast steel. The main purpose of these coatings is protection against the high temperature corrosion, especially at high carburizing potential atmosphere. Coatings were obtained on cast steel type G–XNiCrSi36–18 with the following methods: pack cementation, paste method, cast method and slurry cementation. The phase composition, thickness and morphology of coatings were determined. Coatings capacity of carbon diffusion inhibition and thermal shocks resistance of coatings were determined with different methods. It was found, that all of the coatings reduce carbon diffusion in different degree and all coatings liable to degradation in consequence cracking and oxidation. Coating life time is mainly dependent on morphology, phase composition and service condition (thermal shocks first of all.

Performances of a HGCDTE APD Based Detector with Electric Cooling for 2-μm DIAL/IPDA Applications

Directory of Open Access Journals (Sweden)

Dumas A.

2016-01-01

Full Text Available In this work we report on design and testing of an HgCdTe Avalanche Photodiode (APD detector assembly for lidar applications in the Short Wavelength Infrared Region (SWIR : 1,5 - 2 μm. This detector consists in a set of diodes set in parallel -making a 200 μm large sensitive area- and connected to a custom high gain TransImpedance Amplifier (TIA. A commercial four stages Peltier cooler is used to reach an operating temperature of 185K. Crucial performances for lidar use are investigated : linearity, dynamic range, spatial homogeneity, noise and resistance to intense illumination.

Modeling heat resistance of Bacillus weihenstephanensis and Bacillus licheniformis spores as function of sporulation temperature and pH.

Science.gov (United States)

Baril, Eugénie; Coroller, Louis; Couvert, Olivier; Leguérinel, Ivan; Postollec, Florence; Boulais, Christophe; Carlin, Frédéric; Mafart, Pierre

2012-05-01

Although sporulation environmental factors are known to impact on Bacillus spore heat resistance, they are not integrated into predictive models used to calculate the efficiency of heating processes. This work reports the influence of temperature and pH encountered during sporulation on heat resistance of Bacillus weihenstephanensis KBAB4 and Bacillus licheniformis AD978 spores. A decrease in heat resistance (δ) was observed for spores produced either at low temperature, at high temperature or at acidic pH. Sporulation temperature and pH maximizing the spore heat resistance were identified. Heat sensitivity (z) was not modified whatever the sporulation environmental factors were. A resistance secondary model inspired by the Rosso model was proposed. Sporulation temperatures and pHs minimizing or maximizing the spore heat resistance (T(min(R)), T(opt(R)), T(max(R)), pH(min(R)) and pH(opt(R))) were estimated. The goodness of the model fit was assessed for both studied strains and literature data. The estimation of the sporulation temperature and pH maximizing the spore heat resistance is of great interest to produce spores assessing the spore inactivation in the heating processes applied by the food industry. Copyright © 2011 Elsevier Ltd. All rights reserved.

Aluminide protective coatings on high–temperature creep resistant cast steel

OpenAIRE

J. Kubicki; A. Kochmańska

2009-01-01

This paper presents the results of research on aluminide protective coatings manufactured on high–temperature creep resistant cast steel. The main purpose of these coatings is protection against the high temperature corrosion, especially at high carburizing potential atmosphere. Coatings were obtained on cast steel type G–XNiCrSi36–18 with the following methods: pack cementation, paste method, cast method and slurry cementation. The phase composition, thickness and morphology of coatings were...

Dependence of defect introduction on temperature and resistivity and some long-term annealing effects

Science.gov (United States)

Brucker, G. J.

1971-01-01

The effort reported here represents data of lithium properties in bulk-silicon samples before and after irradiation for analytical information required to characterize the interactions of lithium with radiation-induced defects in silicon. A model of the damage and recovery mechanisms in irradiated-lithium-containing solar cells is developed based on making measurements of the Hall coefficient and resistivity of samples irradiated by 1-MeV electrons. Experiments on bulk samples included Hall coefficient and resistivity measurements taken as a function of: (1) bombardment temperature, (2) resistivity, (3) fluence, (4) oxygen concentration, and (5) annealing time at temperatures from 300 to 373 K.

Investigate the electrical and thermal properties of the low temperature resistant silver nanowire fabricated by two-beam laser technique

Science.gov (United States)

He, Gui-Cang; Dong, Xian-Zi; Liu, Jie; Lu, Heng; Zhao, Zhen-Sheng

2018-05-01

A two-beam laser fabrication technique is introduced to fabricate the single silver nanowire (AgNW) on polyethylene terephthalate (PET) substrate. The resistivity of the AgNW is (1.31 ± 0.05) × 10-7 Ω·m, which is about 8 times of the bulk silver resistivity (1.65 × 10-8 Ω·m). The AgNW electrical resistance is measured in temperature range of 10-300 K and fitted with the Bloch-Grüneisen formula. The fitting results show that the residue resistance is 153 Ω, the Debye temperature is 210 K and the electron-phonon coupling constant is (5.72 ± 0.24) × 10-8 Ω·m. Due to the surface scattering, the Debye temperature and the electron-phonon coupling constant are lower than those of bulk silver, and the residue resistance is bigger than that of bulk silver. Thermal conductivity of the single AgNW is calculated in the corresponding temperature range, which is the biggest at the temperature approaching the Debye temperature. The AgNW on PET substrate is the low temperature resistance material and is able to be operated stably at such a low temperature of 10 K.

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...

Fabrication of resistive plate chamber using bakelite

International Nuclear Information System (INIS)

Neog, Himangshu; Bhuyan, M.R.; Biswas, S.; Mohanty, B.; Mohanty, Rudranarayan; Rudra, Sharmili; Sahu, P.K.; Sahu, S.

2014-01-01

Now a days Resistive Plate Chamber (RPC) is one of the most important detectors in the High Energy Physics (HEP) experiments. RPC is a gas filled detector utilizing a constant and uniform electric field produced between two parallel electrode plates made of a material with high bulk resistivity e.g. glass or bakelite. RPC has good time resolution (1-2 ns) and spatial resolution (∼ cm). The high resistance of RPC plate limits the spark size produced after the ionization of gas due to the passing charged particle. This contribution discusses building of a RPC using bakelite (local sources) and the measurement of the surface resistivity of the detector

Corrosion resistant coatings suitable for elevated temperature application

Science.gov (United States)

Chan, Kwai S [San Antonio, TX; Cheruvu, Narayana Sastry [San Antonio, TX; Liang, Wuwei [Austin, TX

2012-07-31

The present invention relates to corrosion resistance coatings suitable for elevated temperature applications, which employ compositions of iron (Fe), chromium (Cr), nickel (Ni) and/or aluminum (Al). The compositions may be configured to regulate the diffusion of metals between a coating and a substrate, which may then influence coating performance, via the formation of an inter-diffusion barrier layer. The inter-diffusion barrier layer may comprise a face-centered cubic phase.

Performance evaluation of PFBR wire type sodium leak detectors

International Nuclear Information System (INIS)

Vijayakumar, G.; Rajan, K.K.; Nashine, B.K.; Chandramouli, S.; Madhusoodanan, K.; Kalyanasundaram, P.

2011-01-01

Highlights: → Performance evaluation of wire type leak detectors was conducted in LEENA facility by creating sodium leaks. → The lowest leak rate of 214 g/h was detected in 50 min and the highest detection time was 6 h for a leak rate of 222 g/h. → Factors affecting the leak detection time are packing density of thermal insulation, layout of heater, temperature, etc. → Relationship between leak rate and detection time was established and a leak rate of 100 g/h is likely to be detected in 11.1 h. → Contact resistance of leaked sodium increased to 3.5 kilo ohms in 20 h. - Abstract: Wire type leak detectors working on conductivity principle are used for detecting sodium leak in the secondary sodium circuits of fast breeder reactors. It is required to assess the performance of these detectors and confirm that they are meeting the requirements. A test facility by name LEENA was constructed at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam to test the wire type leak detector lay out by simulating different sodium leak rates. This test facility consists of a sodium dump tank, a test vessel, interconnecting pipelines with valves, micro filter and test section with leak simulators. There are three different test sections in the test set up of length 1000 mm each. These test sections simulate piping of Prototype Fast Breeder Reactor (PFBR) secondary circuit and the wire type leak detector layout in full scale. All test sections are provided with leak simulators. A leak simulator consists of a hole of size one mm drilled in the test section and closed with a tapered pin. The tapered pin position in the hole is adjusted by a screw mechanism and there by the annular gap of flow area is varied for getting different leak rates. Various experiments were conducted to evaluate the performance of the leak detectors by creating different sodium leak rates. This paper deals with the details of wire type leak detector layout for the secondary sodium circuit of

Detectors for the Atacama Cosmology Telescope

Science.gov (United States)

Marriage, Tobias Andrew

The Atacama Cosmology Telescope (ACT) will make measurements of the brightness temperature anisotropy in the Cosmic Microwave Background (CMB) on degree to arcminute angular scales. The ACT observing site is located 5200 m near the top of Cerro Toco in the Atacama Desert of northern Chile. This thesis presents research on the detectors which capture the image of the CMB formed at ACT's focal plane. In the first chapter, the primary brightness temperature fluctuations in the Cosmic Microwave Background are reviewed. In Chapter 2, a calculation shows how the CMB brightness is translated by ACT to an input power to the detectors. Chapter 3 describes the ACT detectors in detail and presents the response and sensitivity of the detectors to the input power computed in Chapter 2. Chapter 4 describes the detector fabrication at NASA Goddard Space Flight Center. Chapter 5 summarizes experiments which characterize the ACT detector performance.

The Standard Temperature Calibration Center of the CEN Saclay

International Nuclear Information System (INIS)

Liermann, J.

1978-01-01

The first part of this article describes the instruments available at the Standard Temperature Calibration Center of the CEN Saclay. At the moment the Center has been approved by the BNM to make calibrations between 0 and 1050 0 C, but the Center has recently developed some ovens which will allow calibrations up to 2000 0 C. The Center can also perform thermal and mechanical tests on detector components under the influence of external factors. The second part concerns the development of platinum-resistance high temperature thermometer. The calibrations by comparison between 0 and 1000 0 C are, at the moment, made by using platinum resistance thermometer as a reference up to 630 0 C and a platinum-rhodied/platinum thermocouple above 630 0 C. The use of only one reference could represent for a calibration center a great improvement. For this reason a platinum-resistance high temperature thermometer has been developed. Great care was taken during the conceptual design and during the selection and the assembly of each component [fr

Fracture Resistances of Y_2O_3 Particle Dispersion Strengthened 9Cr Steel at Room Temperature and High Temperatures

International Nuclear Information System (INIS)

Yoon, Ji Hyun; Kang, Suk Hoon; Lee, Yongbok; Kim, Sung Soo

2012-01-01

The fracture resistance and tensile properties of Y_2O_3 oxide dispersion strengthened steel containing 9 wt% Cr (9Cr-ODS) were measured at various temperatures up to 700°C. The fracture characteristics were compared with those of commercial E911 ferritic/martensitic steel. The strength of 9Cr-ODS was at least 30% higher than that of E911 steel at the test temperatures below 500°C. The strength difference between the two materials was almost diminished at 700°C. 9Cr-ODS showed cleavage fracture behavior at room temperature and unstable crack growth behaviors at 300°C and 500°C. The J-R fracture resistance of 9Cr-ODS was much lower than that of E911 steel at all temperatures. It was deduced that the coarse Cr_2O_3 particles that were formed during the alloying process provided the crack initiation sites of cleavage fracture in 9Cr-ODS.

NEET Enhanced Micro-Pocket Fission Detector for High Temperature Reactors - FY16 Status Report

Energy Technology Data Exchange (ETDEWEB)

Unruh, Troy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Reichenberger, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stevenson, Sarah [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tsai, Kevin [Idaho National Lab. (INL), Idaho Falls, ID (United States); McGregor, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-09-01

A collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Atomic Energy Agency, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), has been initiated by the Nuclear Energy Enabling Technologies (NEET) Advanced Sensors and Instrumentation (ASI) program for developing and testing High Temperature Micro-Pocket Fission Detectors (HT MPFD), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package for temperatures up to 800 °C. The MPFD technology utilizes a small, multi-purpose, robust, in-core fission chambers and thermocouple. As discussed within this report, the small size, variable sensitivity, and increased accuracy of the MPFD technology represent a revolutionary improvement over current methods used to support irradiations in US Material Test Reactors (MTRs). Previous research conducted through NEET ASI1-3 has shown that the MPFD technology could be made robust and was successfully tested in a reactor core. This new project will further the MPFD technology for higher temperature regimes and other reactor applications by developing a HT MPFD suitable for temperatures up to 800 °C. This report summarizes the research progress for year two of this three year project. Highlights from research accomplishments include: • Continuation of a joint collaboration between INL, KSU, and CEA. Note that CEA is participating at their own expense because of interest in this unique new sensor. • An updated parallel wire HT MPFD design was developed. • Program support for HT MPFD deployments was given to Accident Tolerant Fuels (ATF) and Advanced Gas-cooled Reactor (AGR) irradiation test programs. • Quality approved materials for HT MPFD construction were procured by irradiation test programs for upcoming deployments. • KSU improved and performed electrical contact and fissile material plating. �

Hydrogen detector

International Nuclear Information System (INIS)

Kumagaya, Hiromichi; Yoshida, Kazuo; Sanada, Kazuo; Chigira, Sadao.

1994-01-01

The present invention concerns a hydrogen detector for detecting water-sodium reaction. The hydrogen detector comprises a sensor portion having coiled optical fibers and detects hydrogen on the basis of the increase of light transmission loss upon hydrogen absorption. In the hydrogen detector, optical fibers are wound around and welded to the outer circumference of a quartz rod, as well as the thickness of the clad layer of the optical fiber is reduced by etching. With such procedures, size of the hydrogen detecting sensor portion can be decreased easily. Further, since it can be used at high temperature, diffusion rate is improved to shorten the detection time. (N.H.)

Optical characterization of wide-gap detector-grade semiconductors

International Nuclear Information System (INIS)

Elshazly, E.S.

2011-01-01

Wide bandgap semiconductors are being widely investigated because they have the potential to satisfy the stringent material requirements of high resolution, room temperature gamma-ray spectrometers. In particular, Cadmium Zinc Telluride (Cd 1-x Zn x Te, x∼0.1) and Thallium Bromide (Tl Br), due to their combination of high resistivity, high atomic number and good electron mobility, have became very promising candidates for use in X- and gamma-ray detectors operating at room temperature. In this study, carrier trapping times were measured in CZT and Tl Br as a function of temperature and material quality. Carrier lifetimes and tellurium inclusion densities were measured in detector-grade Cadmium Zinc Telluride (CZT) crystals grown by the High Pressure Bridgman method and Modified Bridgman method. Excess carriers were produced in the material using a pulsed YAG laser with a 1064 nm wavelength and 7 ns pulse width. Infrared microscopy was used to measure the tellurium defect densities in CZT crystals. The electronic decay was optically measured at room temperature. Spatial mapping of lifetimes and defect densities in CZT was performed to determine the relationship between defect density and electronic decay. A significant and strong correlation was found between the volume fraction of tellurium inclusions and the carrier trapping time. Carrier trapping times and tellurium inclusions were measured in CZT in the temperature range from 300 K to 110 K and the results were analyzed using a theoretical trapping model. Spatial mapping of carrier trapping times and defect densities in CZT was performed to determine the relationship between defect density and electronic decay. While a strong correlation between trapping time and defect density of tellurium inclusions was observed, there was no significant change in the trap energy. Carrier trapping times were measured in detector grade thallium bromide (Tl Br) and compared with the results for cadmium zinc telluride (CZT) in

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)

R&D on a new type of micropattern gaseous detector: The Fast Timing Micropattern detector

Energy Technology Data Exchange (ETDEWEB)

Abbaneo, D.; Abbas, M. [CERN, Geneva (Switzerland); Abbrescia, M. [INFN Bari and University of Bari, Bari (Italy); Akl, M. Abi [Texas A& M University at Qatar, Doha (Qatar); Aboamer, O. [Academy of Scientific Research and Technology, Egyptian Network of High Energy Physics, ASRT-ENHEP, Cairo (Egypt); Acosta, D. [University of Florida, Gainesville (United States); Ahmad, A. [National Center for Physics, Quaid-i-Azam University Campus, Islamabad (Pakistan); Ahmed, W. [INFN Bari and University of Bari, Bari (Italy); Aleksandrov, A. [Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); Altieri, P. [INFN Bari and University of Bari, Bari (Italy); Asawatangtrakuldee, C. [Peking University, Beijing (China); Aspell, P. [CERN, Geneva (Switzerland); Assran, Y. [Academy of Scientific Research and Technology, Egyptian Network of High Energy Physics, ASRT-ENHEP, Cairo (Egypt); Awan, I. [National Center for Physics, Quaid-i-Azam University Campus, Islamabad (Pakistan); Bally, S. [CERN, Geneva (Switzerland); Ban, Y. [Peking University, Beijing (China); Banerjee, S. [Saha Institute of Nuclear Physics, Kolkata (India); Barashko, V. [University of Florida, Gainesville (United States); Barria, P. [Universite Libre de Bruxelles, Brussels (Belgium); Bencze, G. [Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, Budapest (Hungary); and others

2017-02-11

This contribution introduces a new type of Micropattern Gaseous Detector, the Fast Timing Micropattern (FTM) detector, utilizing fully Resistive WELL structures. The structure of the prototype will be described in detail and the results of the characterization study performed with an X-ray gun will be presented, together with the first results on time resolution based on data collected with muon/pion test beams.

Development of new hole-type avalanche detectors and the first results of their applications

CERN Document Server

Charpak, Georges; Breuil, P.; Di Mauro, A.; Martinengo, P.; Peskov, V.

2008-01-01

We have developed a new detector of photons and charged particles- a hole-type structure with electrodes made of a double layered resistive material: a thin low resistive layer coated with a layer having a much higher resistivity. One of the unique features of this detector is its capability to operate at high gas gains (up to 10E4) in air or in gas mixtures with air. They can also operate in a cascaded mode or be combined with other detectors, for example with GEM. This opens new avenues in their applications. Several prototypes of these devices based on new detectors and oriented on practical applications were developed and successfully tested: a detector of soft X-rays and alpha particles, a flame sensor, a detector of dangerous gases. All of these detectors could operate stably even in humid air and/or in dusty conditions. The main advantages of these detectors are their simplicity, low cost and high sensitivity. For example, due to the avalanche multiplication, the detectors of flames and dangerous gases...

Influence of Compaction Temperature on Resistance Under Monotonic Loading of Crumb-Rubber Modified Hot-Mix Asphalts

Directory of Open Access Journals (Sweden)

Hugo A. Rondón-Quintana

2012-12-01

Full Text Available The influence of compaction temperature on resistance under mono-tonic loading (Marshall of Crumb-Rubber Modified (CRM Hot-Mix As-phalt (HMA was evaluated. The emphasis of this study was the applica-tion in Bogotá D.C. (Colombia. In this city the compaction temperature of HMA mixtures decreases, compared to the optimum, in about 30°C. Two asphalt cements (AC 60-70 and AC 80-100 were modified. Two particle sizes distribution curve were used. The compaction temperatures used were 120, 130, 140 and 150°C. The decrease of the compaction tempera-ture produces a small decrease in resistance under monotonic loading of the modified mixtures tested. Mixtures without CRM undergo a lineal decrease in its resistance of up to 34%.

Influence of Compaction Temperature on Resistance Under Monotonic Loading of Crumb-Rubber Modified Hot-Mix Asphalts

Directory of Open Access Journals (Sweden)

Hugo A. Rondón-Quintana

2012-12-01

Full Text Available The influence of compaction temperature on resistance under monotonic loading (Marshall of Crumb-Rubber Modified (CRM Hot-Mix Asphalt (HMA was evaluated. The emphasis of this study was the application in Bogotá D.C. (Colombia. In this city the compaction temperature of HMA mixtures decreases, compared to the optimum, in about 30°C. Two asphalt cements (AC 60-70 and AC 80-100 were modified. Two particle sizes distribution curve were used. The compaction temperatures used were 120, 130, 140 and 150°C. The decrease of the compaction temperature produces a small decrease in resistance under monotonic loading of the modified mixtures tested. Mixtures without CRM undergo a lineal decrease in its resistance of up to 34%.

Development and evaluation of a HEPA filter for increased strength and resistance to elevated temperature

International Nuclear Information System (INIS)

Gilbert, H.; Bergman, W.; Fretthold, J.K.

1993-01-01

We have completed a preliminary study of an improved HEPA filter for increased strength and resistance to elevated temperature to improve the reliability of the standard deep pleated HEPA filter under accident conditions. The improvements to the HEPA filter consist of a silicone rubber sealant and a new HEPA medium reinforced with a glass cloth. Three prototype filters were built and evaluated for temperature and pressure resistance and resistance to rough handling. The temperature resistance test consisted of exposing the HEPA filter to 1,000 scan (1,700 m 3 /hr) at 700 degrees F (371 degrees C) for five minutes.The pressure resistance test consisted of exposing the HEPA filter to a differential pressure of 10 in. w.g. (2.5 kPa) using a water saturated air flow at 95 degrees F (35 degrees C). For the rough handling test, we used a vibrating machine designated the Q110. DOP filter efficiency tests were performed before and after each of the environmental tests. In addition to following the standard practice of using a separate new filter for each environmental test, we also subjected the same filter to the elevated temperature test followed by the pressure resistance test. The efficiency test results show that the improved HEPA filter is significantly better than the standard HEPA filter. Further studies are recommended to evaluate the improved HEPA filter and to assess its performance under more severe accident conditions

Properties of CMOS devices and circuits fabricated on high-resistivity, detector-grade silicon

International Nuclear Information System (INIS)

Holland, S.

1991-11-01

A CMOS process that is compatible with silicon p-i-n radiation detectors has been developed and characterized. A total of twelve mask layers are used in the process. The NMOS device is formed in a retrograde well while the PMOS device is fabricated directly in the high-resistivity silicon. Isolation characteristics are similar to a standard foundary CMOS process. Circuit performance using 3 μm design rules has been evaluated. The measured propagation delay and power-delay product for a 51-stage ring oscillator was 1.5 ns and 43 fJ, respectively. Measurements on a simple cascode amplifier results in a gain-bandwidth product of 200 MHz at a bias current of 15 μA. The input-referred noise of the cascode amplifier is 20 nV/√Hz at 1 MHz

Development of bonded semiconductor device for high counting rate high efficiency photon detectors

International Nuclear Information System (INIS)

Kanno, Ikuo

2008-01-01

We are trying to decrease dose exposure in medical diagnosis by way of measuring the energy of X-rays. For this purpose, radiation detectors for X-ray energy measurement with high counting rate should be developed. Direct bonding of Si wafers was carried out to make a radiation detector, which had separated X-ray absorber and detector. The resistivity of bonding interface was estimated with the results of four-probe measurements and model calculations. Direct bonding of high resistivity p and n-Si wafers was also performed. The resistance of the pn bonded diode was 0.7 MΩ. The resistance should be increased in the future. (author)

The BABAR Detector

Energy Technology Data Exchange (ETDEWEB)

Luth, Vera G

2001-05-18

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

Effect of heat treatment conditions on stress corrosion cracking resistance of alloy X-750 in high temperature water

International Nuclear Information System (INIS)

Yonezawa, Toshio; Onimura, Kichiro; Sakamoto, Naruo; Sasaguri, Nobuya; Susukida, Hiroshi; Nakata, Hidenori.

1984-01-01

In order to improve the resistance of the Alloy X-750 in high temperature and high purity water, the authors investigated the influence of heat treatment condition on the stress corrosion cracking resistance of the alloy. This paper describes results of the stress corrosion cracking test and some discussion on the mechanism of the stress corrosion cracking of Alloy X-750 in deaerated high temperature water. The following results were obtained. (1) The stress corrosion cracking resistance of Alloy X-750 in deaerated high temperature water remarkably depended upon the heat treatment condition. The materials solution heat treated and aged within temperature ranges from 1065 to 1100 0 C and from 704 to 732 0 C, respectively, have a good resistance to the stress corrosion cracking in deaerated high temperature water. Especially, water cooling after the solution heat treatment gives an excellent resistance to the stress corrosion cracking in deaerated high temperature water. (2) Any correlations were not observed between the stress corrosion cracking susceptibility of Alloy X-750 in deaerated high temperature water and grain boundary chromium depleted zones, precipitate free zones and the grain boundary segregation of impurity elements and so on. It appears that there are good correlations between the stress corrosion cracking resistance of the alloy in the environment and the kinds, morphology and coherency of precipitates along the grain boundaries. (author)

Temperature and concentration dependences of the electrical resistivity for alloys of plutonium with americium under normal conditions

Science.gov (United States)

Tsiovkin, Yu. Yu.; Povzner, A. A.; Tsiovkina, L. Yu.; Dremov, V. V.; Kabirova, L. R.; Dyachenko, A. A.; Bystrushkin, V. B.; Ryabukhina, M. V.; Lukoyanov, A. V.; Shorikov, A. O.

2010-01-01

The temperature and concentration dependences of the electrical resistivity for alloys of americium with plutonium are analyzed in terms of the multiband conductivity model for binary disordered substitution-type alloys. For the case of high temperatures ( T > ΘD, ΘD is the Debye temperature), a system of self-consistent equations of the coherent potential approximation has been derived for the scattering of conduction electrons by impurities and phonons without any constraints on the interaction intensity. The definitions of the shift and broadening operator for a single-electron level are used to show qualitatively and quantitatively that the pattern of the temperature dependence of the electrical resistivity for alloys is determined by the balance between the coherent and incoherent contributions to the electron-phonon scattering and that the interference conduction electron scattering mechanism can be the main cause of the negative temperature coefficient of resistivity observed in some alloys involving actinides. It is shown that the great values of the observed resistivity may be attributable to interband transitions of charge carriers and renormalization of their effective mass through strong s-d band hybridization. The concentration and temperature dependences of the resistivity for alloys of plutonium and americium calculated in terms of the derived conductivity model are compared with the available experimental data.

Charged corpuscular beam detector

Energy Technology Data Exchange (ETDEWEB)

Hikawa, H; Nishikawa, Y

1970-09-29

The present invention relates to a charged particle beam detector which prevents transient phenomena disturbing the path and focusing of a charged particle beam travelling through a mounted axle. The present invention provides a charged particle beam detector capable of decreasing its reaction to the charge in energy of the charged particle beam even if the relative angle between the mounted axle and the scanner is unstable. The detector is characterized by mounting electrically conductive metal pieces of high melting point onto the face of a stepped, heat-resistant electric insulating material such that the pieces partially overlap each other and individually provide electric signals, whereby the detector is no longer affected by the beam. The thickness of the metal piece is selected so that an eddy current is not induced therein by an incident beam, thus the incident beam is not affected. The detector is capable of detecting a misaligned beam since the metal pieces partially overlap each other.

Development of Ultra-Fast Silicon Detectors for 4D tracking

Science.gov (United States)

Staiano, A.; Arcidiacono, R.; Boscardin, M.; Dalla Betta, G. F.; Cartiglia, N.; Cenna, F.; Ferrero, M.; Ficorella, F.; Mandurrino, M.; Obertino, M.; Pancheri, L.; Paternoster, G.; Sola, V.

2017-12-01

In this contribution we review the progress towards the development of a novel type of silicon detectors suited for tracking with a picosecond timing resolution, the so called Ultra-Fast Silicon Detectors. The goal is to create a new family of particle detectors merging excellent position and timing resolution with GHz counting capabilities, very low material budget, radiation resistance, fine granularity, low power, insensitivity to magnetic field, and affordability. We aim to achieve concurrent precisions of ~ 10 ps and ~ 10 μm with a 50 μm thick sensor. Ultra-Fast Silicon Detectors are based on the concept of Low-Gain Avalanche Detectors, which are silicon detectors with an internal multiplication mechanism so that they generate a signal which is factor ~10 larger than standard silicon detectors. The basic design of UFSD consists of a thin silicon sensor with moderate internal gain and pixelated electrodes coupled to full custom VLSI chip. An overview of test beam data on time resolution and the impact on this measurement of radiation doses at the level of those expected at HL-LHC is presented. First I-V and C-V measurements on a new FBK sensor production of UFSD, 50 μm thick, with B and Ga, activated at two diffusion temperatures, with and without C co-implantation (in Low and High concentrations), and with different effective doping concentrations in the Gain layer, are shown. Perspectives on current use of UFSD in HEP experiments (UFSD detectors have been installed in the CMS-TOTEM Precision Protons Spectrometer for the forward physics tracking, and are currently taking data) and proposed applications for a MIP timing layer in the HL-LHC upgrade are briefly discussed.

Two-dimensional position sensitive Si(Li) detector

International Nuclear Information System (INIS)

Walton, J.T.; Hubbard, G.S.; Haller, E.E.; Sommer, H.A.

1978-11-01

Circular, large-area two-dimensional Si(Li) position sensitive detectors have been fabricated. The detectors employ a thin lithium-diffused n + resisitive layer for one contact and a boron implanted p + resistive layer for the second contact. A position resolution of the order of 100 μm is indicated

Spiral silicon drift detectors

International Nuclear Information System (INIS)

Rehak, P.; Gatti, E.; Longoni, A.; Sampietro, M.; Holl, P.; Lutz, G.; Kemmer, J.; Prechtel, U.; Ziemann, T.

1988-01-01

An advanced large area silicon photodiode (and x-ray detector), called Spiral Drift Detector, was designed, produced and tested. The Spiral Detector belongs to the family of silicon drift detectors and is an improvement of the well known Cylindrical Drift Detector. In both detectors, signal electrons created in silicon by fast charged particles or photons are drifting toward a practically point-like collection anode. The capacitance of the anode is therefore kept at the minimum (0.1pF). The concentric rings of the cylindrical detector are replaced by a continuous spiral in the new detector. The spiral geometry detector design leads to a decrease of the detector leakage current. In the spiral detector all electrons generated at the silicon-silicon oxide interface are collected on a guard sink rather than contributing to the detector leakage current. The decrease of the leakage current reduces the parallel noise of the detector. This decrease of the leakage current and the very small capacities of the detector anode with a capacitively matched preamplifier may improve the energy resolution of Spiral Drift Detectors operating at room temperature down to about 50 electrons rms. This resolution is in the range attainable at present only by cooled semiconductor detectors. 5 refs., 10 figs

Studies on multigap resistive plate chamber prototypes for the new NeuLAND detector at the R3B experiment at FAIR

Energy Technology Data Exchange (ETDEWEB)

Elvers, Michael; Endres, Janis; Zilges, Andreas [IKP, Universitaet Koeln (Germany); Aumann, Tom; Boretzky, Konstanze; Hehner, Joerg; Heil, Michael; Prokopowicz, Wawrczek; Reifarth, Rene; Schrieder, Gerhard [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); Bemmerer, Daniel; Stach, Daniel; Wagner, Andreas; Yakorev, Dmitry [Forschungszentrum Dresden-Rossendorf (FZD), Dresden (Germany); Kratz, Jens Volker; Rossi, Dominic [Johannes-Gutenberg-Universitaet, Mainz (Germany)

2009-07-01

The NeuLAND detector is part of the R3B experiment at FAIR and will detect neutrons between 0.2 and 1 GeV. The high energy neutrons are converted to charged particles, mainly protons, which are detected by Multigap Resistive Plate Chambers (MRPC). For the detector, a time resolution of {sigma}{sub t} < 100 ps and a position resolution of {sigma}{sub x,y,z} {approx}1 cm is required for given flight paths in the range from 10 to 35 m. An active area of 2 x 2 m{sup 2} of the neutron detector at a distance of 12.5 m to the target will match the angular acceptance of {+-}80 mrad for the neutrons defined by the gap of the superconducting dipole magnet. The salient features of the prototypes are described, as well as electrical measurements and studies with cosmic rays.

The 150 ns detector project: progress with small detectors

International Nuclear Information System (INIS)

Warburton, W.K.; Russell, S.R.; Kleinfelder, Stuart A.; Segal, Julie

1994-01-01

This project's long term goal is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1x256 1D and 8x8 2D detectors, 256x256 2D detectors and, finally, 1024x1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front end preamplifiers are being integrated first, since their design and performance are both the most unusual and also critical to the project's success. Similarly, our early work is also concentrating on devising and perfecting detector structures which are thick enough (1 mm) to absorb over 99% of the incident X-rays in the energy range of interest. In this paper we discuss our progress toward the 1x256 1D and 8x8 2D detectors. We have fabricated sample detectors at Stanford's Center for Integrated Systems and are preparing both to test them individually and to wirebond them to the preamplifier samples to produce our first working small 1D and 2D detectors. We will describe our solutions to the design problems associated with collecting charge in less than 30 ns from 1 mm thick pixels in high resistivity silicon. We have constructed and tested the front end of our preamplifier design using a commercial 1.2 μm CMOS technology and are moving on to produce a few channels of the complete preamplifier, including a switchable gain stage and output stage. We will discuss both the preamplifier design and our initial test results. ((orig.))

The 150 ns detector project: progress with small detectors

Energy Technology Data Exchange (ETDEWEB)

Warburton, W.K. (X-ray Instrumentation Associates, 2513 Charleston Rd, Ste 207, Mountain View, CA 94043 (United States)); Russell, S.R. (X-ray Instrumentation Associates, 2513 Charleston Rd, Ste 207, Mountain View, CA 94043 (United States)); Kleinfelder, Stuart A. (VLSI Physics, 19 Drury Lane, Berkeley, CA 94705 (United States)); Segal, Julie (Integrated Ckts Lab., Dept. of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States))

1994-09-01

This project's long term goal is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1x256 1D and 8x8 2D detectors, 256x256 2D detectors and, finally, 1024x1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front end preamplifiers are being integrated first, since their design and performance are both the most unusual and also critical to the project's success. Similarly, our early work is also concentrating on devising and perfecting detector structures which are thick enough (1 mm) to absorb over 99% of the incident X-rays in the energy range of interest. In this paper we discuss our progress toward the 1x256 1D and 8x8 2D detectors. We have fabricated sample detectors at Stanford's Center for Integrated Systems and are preparing both to test them individually and to wirebond them to the preamplifier samples to produce our first working small 1D and 2D detectors. We will describe our solutions to the design problems associated with collecting charge in less than 30 ns from 1 mm thick pixels in high resistivity silicon. We have constructed and tested the front end of our preamplifier design using a commercial 1.2 [mu]m CMOS technology and are moving on to produce a few channels of the complete preamplifier, including a switchable gain stage and output stage. We will discuss both the preamplifier design and our initial test results. ((orig.))

Charged projectile spectrometry using solid-state nuclear track detector of the PM-355 type

Directory of Open Access Journals (Sweden)

Malinowska Aneta

2015-09-01

Full Text Available To use effectively any radiation detector in high-temperature plasma experiments, it must have a lot of benefits and fulfill a number of requirements. The most important are: a high energy resolution, linearity over a wide range of recorded particle energy, high detection efficiency for these particles, a long lifetime and resistance to harsh conditions existing in plasma experiments and so on. Solid-state nuclear track detectors have been used in our laboratory in plasma experiments for many years, but recently we have made an attempt to use these detectors in spectroscopic measurements performed on some plasma facilities. This paper presents a method that we used to elaborate etched track diameters to evaluate the incident projectile energy magnitude. The method is based on the data obtained from a semiautomatic track scanning system that selects tracks according to two parameters, track diameter and its mean gray level.

Design of an ionization diffusion chamber detector

International Nuclear Information System (INIS)

Sugiarto, S.

1976-01-01

Prototype of an Ionization Diffusion Chamber detector has been made. It is a silindrical glass, 20 cm in diameter, 13,5 cm in height, air gas filled, operated at room pressure and room temperature at the top of this instrument while for the box temperature dry ice (CO 2 solid) temperature is used. This detector is ready for seeing alpha and beta particle tracks. (author)

Study on microstructure and high temperature wear resistance of laser cladded nuclear valve clack

International Nuclear Information System (INIS)

Zhang Chunliang; Chen Zichen

2002-01-01

Laser cladding of Co-base alloy on the nuclear valve-sealing surface are performed with a 5 kW CO 2 transverse flowing laser. The microstructure and the high temperature impact-slide wear resistance of the laser cladded coating and the plasma cladded coating are studied. The results show that the microstructure, the dilution rate and the high temperature impact-slide wear resistance of the laser cladded coating have obvious advantages over the spurt cladding processing

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

Monolithic pixels on moderate resistivity substrate and sparsifying readout architecture

CERN Document Server

Giubilato, P; Snoeys, W; Bisello, D; Marchioro, A; Battaglia, M; Demaria, L; Mansuy, S C; Pantano, D; Rousset, J; Mattiazzo, S; Kloukinas, K; Potenza, A; Ikemoto, Y; Rivetti, A; Chalmet, P; Mugnier, H; Silvestrin, L

2013-01-01

The LePix projects aim realizing a new generation monolithic pixel detectors with improved performances at lesser cost with respect to both current state of the art monolithic and hybrid pixel sensors. The detector is built in a 90 nm CMOS process on a substrate of moderate resistivity. This allows charge collection by drift while maintaining the other advantages usually offered by MAPS, like having a single piece detector and using a standard CMOS production line. The collection by drift mechanism, coupled to the low capacitance design of the collecting node made possible by the monolithic approach, provides an excellent signal to noise ratio straight at the pixel cell together with a radiation tolerance far superior to conventional un-depleted MAPS. The excellent signal-to-noise performance is demonstrated by the device ability to separate the 6 keV Fe-55 double peak at room temperature. To achieve high granularity (10-20 mu m pitch pixels) over large detector areas maintaining high readout speed, a complet...

Comparative study on the behavior of carbon resistance temperature sensors at low temperatures

International Nuclear Information System (INIS)

Balteanu, Ovidiu; Cristescu, Ioana; Retevoi, Carmen

2000-01-01

The paper presents the behavior of four carbon resistance sensors, which do not have a calibration curve in comparison with two calibrated sensors. To study this behavior, all these sensors were introduced into a column cooled by a hydrogen cryogenerator of Phillips type. For high accuracy measurements, a PC with a data acquisition board incorporated achieved the data processing. The experiment consists of three cooling-heating cycles that allow studying the time stability of the sensor characteristics. The experimental data were used to draw the R = f(T) and error curves for a single cooling-heating cycle. In addition, we found the polynomial regression for the sensors that do not have a calibration curve. In conclusion it results that the carbon resistance sensors have a higher accuracy at low temperature and time stability is very good. (authors)

Oxide layers for silicon detector protection against enviroment effects

International Nuclear Information System (INIS)

Bel'tsazh, E.; Brylovska, I.; Valerian, M.

1986-01-01

It is shown that for protection of silicon detectors of nuclear radiations oxide layers could be used. The layers are produced by electrochemical oxidation of silicon surface with the following low-temperature annealing. These layers have characteristics similar to those for oxide layers produced by treatment of silicon samples at elevated temperature in oxygen flow. To determine properties of oxide layers produced by electrochemical oxidation the α-particle back-scattering method and the method of volt-farad characteristics were used. Protection properties of such layers were checked on the surface-barrier detectors. It was shown that protection properties of such detectors were conserved during long storage at room temperature and during their storage under wet-bulb temperature. Detectors without protection layer have worsened their characteristics

Research of boron conversion coating in neutron detector with boron deposited GEM

International Nuclear Information System (INIS)

Ye Di; Sun Zhijia; Zhou Jianrong; Wang Yanfeng; Yang Guian; Xu Hong; Chen Yuanbai; Xiao Yu; Diao Xungang

2014-01-01

GEM is a flourishing new gas detector and nowadays its technology become more mature. It has outstanding properties, such as excellent position resolution, high counting rate, radiation resistance, simple and flexible signal readout, can be large-area detector, wide application range. Detector with boron deposited GEM uses multilayer GEM with deposited boron film as neutron conversion carrier which reads out the information of neutron shot from the readout electrode with gas amplification from every GEM layer. The detector is high performance which can meet the demands of neutron detector of a new generation. Boron deposited neutron conversion electrode with boron deposited cathode and GEM included is the core part of the detector. As boron is a high-melting-point metalloid (> 2 000 ℃), electroplating and thermal evaporation are inappropriate ways. So finding a way to deposit boron on electrode which can meet the demands become a key technology in the development of neutron detector with boron deposited GEM. Compared with evaporation, sputtering has features such as low deposition temperature, high film purity, nice adhesive, thus is appropriate for our research. Magnetron sputtering is a improved way of sputtering which can get lower sputtering air pressure and higher target voltage, so that we can get better films. Through deposit process, the research uses magnetron sputtering to deposit pure boron film on copper electrode and GEM film. This method can get high quality, nice adhere, high purity, controllable uniformity, low cost film with high speed film formation. (authors)

Neutron spectrometry by diamond detector for nuclear radiation

International Nuclear Information System (INIS)

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

1975-01-01

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

Discovery of the B_{c}(2S) Meson and Development of Pixel Detectors for Future Particle Collider Experiments

CERN Document Server

Wang, Rui

This work involves an analysis of data recorded at the Large Hadron Collider combined with a program to develop detectors for future collider experiments. Using the full 4.9 fb$^{-1}$ of 7 \\TeV~data collected in 2011 and the 19.2 fb$^{-1}$ of 8 \\TeV~data collected in 2012, the $\\Bc(2S)$ meson has been observed with the ATLAS detector in the hadronic decay mode $\\Bc(2S)\\rightarrow \\Bc\\pi^{+}\\pi^{-}$, $\\Bc\\rightarrow J/\\psi\\pi$. This new state has been found in the mass difference distribution with invariant mass $6842 \\pm 7_{stat.} \\pm 4_{syst.}$ \\MeV. To prepare for the high radiation environment at the High Luminosity LHC, diamond sensors are being developed. Their leakage current and resistivity are measured at fluences and temperatures relevant to the ATLAS upgrade. No evidence of dependence of the resistivity on fluence or temperature has been observed for the ranges [-10 $^\\circ$C, +20 $^\\circ$C] and [0, $1.0\\times10^{16} \\rm{n_{eq}/cm^2}$]. To study the radiation damage of the sensors in the ATLAS Pixel...

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.

Resistivity of atomic layer deposition grown ZnO: The influence of deposition temperature and post-annealing