Pdf energy and efficiency calibrations for high purity. High purity germanium hpge is the only radiation detection. The conventional coaxial germanium detector is often referred to as pure ge, hpge, intrinsic ge, or hyperpure ge. Pdf the availability of germanium with less than 1010 acceptorscm3 has enabled us to fabricate and study the performance of. The best choice of high purity germanium hpge detector detector efficiencye the detector efficiency in eq. The germanium crystals used for the fabrication of nuclear radiation detectors are required to have a purity and crystalline perfection which is unsurpassed by any other solid material. These detectors are made of high purity germanium hpge ptype and n, or silicon lithium sili. This detector, based upon emerging silicon drift detector sdd technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium hpge detectors, without the need for liquid nitrogen. The authors declare having no conflict of interest. We use both ptype and ntype germanium and we use diffused, implanted, and barrier contacts to achieve this product variety. The response of a highpurity germanium detector to xrays in the 815kev energy region has been investigated. Introduction use of segmented high purity germanium hpge detectors is foreseen in the gerda experiment germanium detector array 1,2 in the search of neutrinoless doublebeta decay of 76ge.
Other articles where germanium detector is discussed. High purity germanium detector in gammaray spectrometry. Germanium well detectors are made from high purity germanium and can therefore be shipped and stored at room temperature without harm. Ortec offers a broad range of semiconductor photon detectors and options, as can be seen in the figure, covering energies in a range from a few hundred ev to 10mev gamma ray and upper. A semiconductor detector in ionizing radiation detection physics is a device that uses a. High purity germanium detector calibration at isolde.
For the nuclear hobbyist, an hpge opens a window into a fascinating realm of homeaccessible, lowintensity nuclear reactions that are obscured by background in other detectors lacking the superlative resolution. Characterization of high purity germanium point contact. For high purity germanium detectors, the fwhm of the 32. The measured ionization efficiencies of recoiling germanium atoms in germanium are in good agreement with the theory of lindhard and earlier measurements. Installation setup of a highpurity germanium hpge nuclear spectroscopy system. Jra2 is named integrated double beta decay idea and it aims to further develop and integrate the. Lowbackground germanium spectroscopy shields for radiation.
The present disclosure provides a high purity germanium hpge detector, comprising. Performance of the ultrahigh rate germanium uhrge system. On the underground production of high purity germanium detectors mikael hult1, sergey belogurov2, allan caldwell3, josef janicsko3, vasiliy kornoukhov2,4, stefan schonert5 1 european commissionjoint research centreinstitute for reference materials and measurements ecjrcirmm, geel, belgium. The first triple cluster detector was successfully assembled for the next generation highresolution gammaray spectrometer. The performance of the germanium ge detector body monitor that has been recently installed at nrpb chilton is evaluated and compared with the perfo. High purity germanium remains the material of choice for the detection of photons in the range of mev or higher, down to the hard xray range. The present disclosure provides a highpurity germanium hpge detector, comprising. Ruhter lawrence livermore national laboratory livermore, ca 94550 usa abstract we have integrated a small, highlyreliable, electromechanical cryocooler with a high resolution germanium detector for portablefield applications. High purity germanium detectors are mostly used for gamma spectroscopy in nuclear physics, as well as xray spectroscopy.
High purity germanium detector array spie digital library. Calibration of hpge gammaray planar detector system for. Square hole collimators have been fabricated with design parameters that exploit the unique characteristics of the detector. Unlike lithiumdrifted detectors, high purity germanium detectors may be cycled repeatedly between ln 2 and room temperature with no compromise in performance. The detector energy resolution follows a characteristic.
For semiconductor detectors in radio, see detector radio, crystal detector, semiconductor diodes, and rectifier. Therefore we conclude that we have measured recoil events from elastically scattered neutrons inside the germanium detector. The impact of the procedure and geometry on the detector performance was analyzed for eight detectors. What is meant by the detection efficiency at specific gammaray energy. Five things you need to know about using highpurity. A semiconductor detector in ionizing radiation detection physics is a device that uses a semiconductor usually silicon or germanium to measure the effect of incident charged particles or photons. These crystals should not have a net electrically active impurity concentration greater than 10 l0 cm. If silicon or germanium of normal semiconductor purity is employed. We present an initial evaluation of a mechanically cooled, highpurity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. Segmented planar high purity germanium detectors were developed. The detectors from the hdm and igex experiments were reprocessed and used in phase 1. Why high purity germanium hpge radiation detection.
Use of a highpurity germanium semiconductor detector for. As a result, the fabrication process of small planar detectors at usd was discussed in great detail. A prototype high purity germanium detector array designed for use in the pulse height analysis mode as a discrete photon energy detector for medical imaging was fabricated and tested. The printed circuit boards pcb containing the cooled electronics. Detector fabrication and performance article pdf available in ieee transactions on nuclear science ns191. Index termsneutrinoless double beta decay, gerda, hpge detector, liquid argon. Why high purity germanium hpge radiation detection technology is superior to other detector technologies for isotope identification synopsis. Digital timing algorithm for high purity germanium detectors knox andrew, university of massachusetts lowell, krzysztof starosta, david miller, constantin vaman, phillip voss, dirk weisshaar, michigan state universitynational superconduction cyclotron labratory the next generation of ray detector arrays will be composed of large volume high. This article is about ionizing radiation detectors.
High purity germanium hpge is widely used xray and. Topsil hps float zone silicon for detectors has the following unique. The germanium detector array, gerda, will search for neutrinoless double beta decay in 76ge at the national gran sasso laboratory of the infn. Youngman, evaluation of a high purity germanium detector body monitor, radiation protection dosimetry, volume 53, issue 14, 1 may 1994. Gamma background studies for the xenon experiment using a high purity germanium detector by jesse isaac angle may 2008 chair. Standard shields are offered with thicknesses of up to 6inches 15cm, and are copper and tin lined to completely encapsulate the lead and eliminate exposure to the user.
What is high purity germanium detector hpge definition. Newly designed lowbackground detector shields for radiation measurement applications. The purpose of this research is to investigate the feasibility of using a high purity germanium double sided strip detector hpgedssd to image special nuclear material snm for use in the field of nuclear nonproliferation. In gerda phasei, reprocessed enrichedge detectors, which were previously. For applications where temperature stability of response is important near. The experiment uses high purity enriched ge crystal diodes as a beta decay source and particle detector. Characterization of high purity germanium point contact detectors with low net impurity concentration. In this case, however, it is advantageous to choose germanium rather than silicon as the detector material. Detailed specifications are available for j16 series room temperature detectors, parallel output arrays, avalanche photodiodes and two color detectors. For applications where temperature stability of response is important near the cutoff, thermoelectrically cooled detectors are available. Highpurity germanium detectors hpge detectors are the best solution for precise gamma and xray spectroscopy. Pulse shapes of recoil events from neutron scattering inside a germanium detector were collected for the first time. Because the issue with leakage current only applies during operation, hpge. To complete the gamma spectroscopy laboratory set caen sys includes in its offer a wide choice of high purity germanium detectors hpge.
We use both ptype and ntype germanium and we use diffused, implanted, and. Comparison of a high purity germanium gamma ray spectrometer. Appendix c truck mounted high purity germanium detector surveys. For photon spectroscopy in the energy region of hundred kev or several mev, much thicker semiconductor. Semiconductor detectors also can be used in gammaray spectroscopy. Both energy resolution and efficiency will be explored as a function of ray energy. Twodetector, 512element high purity germanium camera.
The excellent energy resolution that hpge detectors afford often makes them the detector of choice for applications as diverse as nuclear physics research, medical imaging, homeland security, and environmental monitoring. To free one photoelectron from the pmts photocathode. Two types of geometry were used to fabricate hpge detectors. The highly pure germanium detector is designed to be sensitive to low energy dark matter flux. We present an initial evaluation of a mechanicallycooled, highpurity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. This does not come better than in topsil high purity silicon hps. Energy and efficiency calibrations for high purity germanium gem30195 coaxial detector using k0iaea software. In comparison to silicon detectors, germanium is much more efficient than silicon for radiation detection due to its atomic number being much higher than silicon and due to lower average energy necessary to create an electronhole. Performance of bare highpurity germanium detectors in. Pdf high purity germanium koya4039 gamma detection system. I have a question regarding gamma ray detector, the high purity germanium detector or aka hpge. As a result, the fabrication process of small planar detectors at usd is discussed in great detail. Digital gammaray spectroscopy with high purity germanium.
High purity germanium detector repair conference osti. High purity germanium detector array, proceedings of spie. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4. A prototype high purity germanium detector for high.
Segmentation of pn junction was performed by implantation of boron for the ntype ge and mechanical grooving of the li diffusion. Portable electromechanically cooled highresolution germanium detector kenneth w. The invention discloses a high purity germanium detector, which comprises a high purity germanium crystal, a first electrode and a second electrode, and a conductive protection ring, wherein the high purity germanium crystal has an intrinsicregion exposed surface. Characterization of mechanically cooled high purity germanium. The response of highpurity germanium detectors to xrays. We use cookies to make interactions with our website easy and meaningful, to better understand the use of our services, and to tailor advertising. For more information please contact natsusa at 8606356820.
The high purity germanium spectroscopy detector is used in the detection and analysis of gammaray of environmental objects in nuclear energetics, products of industry and agriculture, medicine, etc. The advantages of the intrinsic radiopurity and excellent spectroscopic performance 2 3 kev full width at half maximum resolution at qbb 2039 kev of hpge detectors have. There are three different effects that can modify the size and shape of a charge cloud as it moves through a germanium detector. The purpose of this project was to develop a compact, modular multichannel xray detector with integrated electronics. Germanium detectors germanium short form catalog in pdf format j16 series detectors are highquality germanium photodiodes designed for the 800 to 1800nm wavelength range.
This summer student project involved the test and calibration of two high purity coaxial germanium gammaray detectors. This work investigates the ability of a high purity germanium detector to perform postdetonation forensics on the debris from several types of nuclear weapons 24 hours after detonation. Calculation of the peak efficiency of highpurity germanium detectors. Signal modeling of highpurity ge detectors with a small read. A brief but very effective description on the basic formation. On the underground production of high purity germanium detectors mikael hult1, sergey belogurov2, allan caldwell3. The dependence of the energy resolution on the shaping parameter will be investigated. Semiconductor detectors find broad application for radiation protection, gamma and xray spectrometry, and as particle detectors. Ssbi can offer the optimum detector for a wide range of applications. On the underground production of high purity germanium. Hyperpure germanium detector introduction the aim of this experiment is to be familia r with a hyperpure germ anium hpge detector used as a ray spectrometer.
Hpge detectors have a 2030x improvement in resolution as compared to that of. Introduction silicon semiconductor detectors described in the previous chapter have depletion depths less than 1 mm, which are sufficient for charged particle spectroscopy or soft xray detection. Evaluation of a high purity germanium detector body. From the photon mean free path in germanium, a detector thickness of the order of 5 cm is required for efficient detection of. Portable electromechanically cooled highresolution. This coaxial detector is available in an energy range of 40kev to 10 mev and offers high efficiency of radiation detection. Germanium detectors are semiconductor diodes having a pin structure in which the intrinsic i region is sensitive to ionizing. On the underground production of high purity germanium detectors.
Calibration of hpge gammaray planar detector system for radioactivity standards tidatrut vichaidid 1, thongchai soodprasert1 and teerasak verapaspong2 abstract quantitative analysis of radioactive materials using efficiency calibration of gamma ray high purity germanium planar detector system has been studied. Ortec provides a comprehensive suite of hpge radiation detector solutions covering an extensive range of energies and for a variety of applications. Using this model and the source term, the predicted response spectrum for each fallout composition was generated and compared using genie spectroscopy software in an attempt to find differentiating features between them. High purity germanium hpge radiation detectors products. The wvalue and energy resolution dependencies on the xray energy have been studied. A highpurity germanium detector was modeled in mcnp6. Making a high purity ge rmanium detector 1 start with highpurity, ntype ge crystal. Ptype point contact germanium detectors and their application in. In comparison to silicon detectors, germanium is much more efficient than silicon for radiation detection due to its atomic number being much higher than silicon and due to lower average energy necessary to create an electronhole pair, which is 3. The following are five things you need to know about the use of hpge detector systems for homeland security applications in the field. The detector array is suspended in a liquid argon cryostat lined with copper and surrounded by an ultrapure water tank. International journal of applied radiation and isotopes, vol. We measured full energy peak efficiency of highpurity germanium detector which is important for gammaray spectrometry experiments.
The ultimate result of this analysis would be the deployment of this detector on an autonomous robot for sample collection and remote analysis. Highpurity germanium for gamma detectors technical. High purity germanium hpge is the only radiation detection technology that provides sufficient information to accurately and reliably identify radionuclides from their passive gamma ray emissions. Presentation mode open print download current view. The core part of the detector consists of three encapsulated, 36fold segmented, highpurity germanium detectors hpge which are operated in a common cryostat. All our measurements were done using highpurity coaxial germanium detector hpge model number 30195 ortec with relative efficiency of cm30% and a resolution of 1.
Energy and efficiency calibrations for high purity. Learn more about ortecs high purity germanium radiation detectors hpge today. The detector consists of an ntype hpge crystal, 60mm in diameter and 90mm in length, with 36fold segmentation of the outer boron implanted contact. Bare highpurity germanium detectors enriched in 76ge will be submerged in liquid argon serving simultaneously as a shield against external radioactivity and as a cooling medium.
Twodetector, 512element high purity germanium camera prototype abstract. High purity germanium hpge detectors remain the recognized gold standard for high resolution gammaray spectroscopy. We measured full energy peak efficiency of high purity germanium detector which is important for gammaray spectrometry experiments. Truck mounted high purity germanium detector surveys this appendix provides figures that were generated using the ineels truck mounted high purity germanium detectors either on a hummer or other fourwheel drive vehicle to perform field screening of the tsf06 area b and tsf26 sites for cs 7.
High purity germanium detector calibration at isolde gu. A cryogenic lownoise jfetcmos preamplifier for the hpge. Performance of bare highpurity germanium detectors in liquid. Otherwise, leakage current induced noise destroys the energy resolution of the detector. Since the operation of hpgebased detectors is possible only at or below the liquid nitrogen temperature, their advantage is mainly the resolution, which matches the fano factor if appropriate cooled electronic readout is used. The ultra high rate germanium uhrge project goal was to develop technology to operate high purity germanium hpge detectors with high throughput 85% in environments with incoming gammaxray event rates r106 s. High purity germanium detectors hpge are not just laboratory instruments anymore. Resolution and efficiency of high purity germanium detector. Physics the xenon dark matter experiment, deployed at the gran sasso national laboratory in italy on march 2006, is a liquid noble gas detector designed to directly detect dark matter. The first gamma ray spectrometer is the one dimensional high purity germanium spectrometer.
Results obtained as a function of the photon input rate, energy resolution, and techniques for correcting for pulse overlap at high count rates will be discussed. Canberra models gc7020 old, from 1990, and gx6020 new, from. Germanium detector how is germanium detector abbreviated. No abrupt variation of wis observed at the germanium k absorptionedge 11. High purity germanium spectroscopy system north american. Characterization of a highpurity germanium detector for. Because germanium has relatively low band gap, these detectors must be cooled in order to reduce the thermal generation of charge carriers thus reverse leakage current to an acceptable level. Pdf the impact of high purity germanium gamma detection system koya4039 will be presented. The detector type is high purity germanium, which is a semiconductor that must be temperature controlled with liquid nitrogen to 77 k due to excessive leakage current at higher temperatures 2. Amorphous germanium age contacts are used for blocking both electrons and holes. Fabrication and characterization of highpurity germanium. Sep 21, 2011 we present an initial evaluation of a mechanicallycooled, high purity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. These detectors are also called highpurity germanium detectors hpge or. Introduction t he germanium detector array, gerda, will search for neutrinoless double beta decay 0 in 76ge 1 with the goal to investigate the nature of neutrinos and their mass.
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