Gamma background studies for the xenon experiment using a high purity germanium detector by jesse isaac angle may 2008 chair. Highpurity germanium hpge radiation detectors are well established as a valuable tool in nuclear science, astrophysics, and nuclear security applications. The present disclosure provides a highpurity germanium hpge detector, comprising. Efficient machine learning approach for optimizing the. The response of a highpurity germanium detector to xrays in the 815kev energy region has been investigated. Otherwise, leakage current induced noise destroys the energy resolution of the detector. Ortec provides a comprehensive suite of hpge radiation detector solutions covering an extensive range of energies and for a variety of applications. The rege is a closedend ntype detector while the xtra is a. Evaluation of a high purity germanium detector body monitor j. Measurement of the potassium content of different food. Detector fabrication and performance article pdf available in ieee transactions on nuclear science ns191. The detector energy resolution follows a characteristic. These are known as the profile gem f and profile gem fx series respectively. Cycle hybrid cryostat as cooling system for the highpurity germanium hpge detector in the rn52 radionuclide monitoring system in tanay, philippines and to assess its benefits to the operation and maintenance of the station.
Detectors highpurity germanium detectors broad energy. Computer modeling of highpurity germanium detectors in. Evaluation of a high purity germanium detector body. Resolution and efficiency of high purity germanium detector a project by abhigyan. We use both ptype and ntype germanium and we use diffused, implanted, and. Both are commercial detectors produced by canberra. A brief but very effective description on the basic formation. High purity germanium hpge crystals are indispensable for radiation detection and fundamental research. Although already of very high purity, the material is further purified with the zone refining technique. High purity germanium detectors are mostly used for gamma spectroscopy in nuclear physics, as well as xray spectroscopy. A highpurity germanium detector was modeled in mcnp6. Technology development of high purity germanium crystals. However, these detectors require cooling to liquid nitrogen temperatures for optimal performance, making a compact imaging system for clinical and preclinical settings unrealistic in the past. Learn more about ortecs high purity germanium radiation detectors hpge today.
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. 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. The invention discloses a kind of high purity germanium detector, including hpge crystal unit array, the hpge crystal unit array includes two or more hpge crystal units, wherein, each includes being located at partial electrode of side andor the first top surface described two or more individual hpge crystal units, and the side of described two or more individual hpge crystal units andor the. The detector calibration was carried out using a certified multigamma source and two reference materials iaea 327, iaea 375. On the underground production of high purity germanium. We present an initial evaluation of a mechanicallycooled, highpurity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. Highpurity germanium detectors the measurements described in the paper wereperformed with two different hpge detectors 2. Simulation study comparing highpurity germanium and. Ssbi can offer the optimum detector for a wide range of applications.
Hpge detectors excel in gammaray spectroscopy, offering excellent energy resolution with large detector sizes. Resolution and efficiency of high purity germanium detector. Emerging role of highpurity germanium detectors for. The impact of the procedure and geometry on the detector performance was analyzed for eight detectors. Highpurity germanium hpge detectors are widely used in nuclear spectroscopy e. Performance of bare highpurity germanium detectors in. Canberra models gc7020 old, from 1990, and gx6020 new, from. For full access to this pdf, sign in to an existing account, or purchase an annual subscription. The theory of response characteristics is explained, and the highresolution measurement results are contrasted with those from a sodium iodide nai. The canberra broad energy ge bege detector covers the energy range of 3 kev to 3 mev like no other. Snm shape can be determined by using a gamma ray imaging system that is capable of imaging either pu239 or u235. 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. Among other applications they will be used in the large enriched germanium experiment for neutrinoless double beta decay legend experiment for the.
Highpurity germanium crystal, hpge planar detector, amorphous semiconductor. The best choice of high purity germanium hpge detector detector efficiencye the detector efficiency in eq. Pdf resolution and efficiency of high purity germanium detector. Characterization of a highpurity germanium detector for. The method utilizes a type of artificial neural network ann called a selforganizing map som to cluster the hpge waveforms based on the shape of their rising edges. 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. To complete the gamma spectroscopy laboratory set caen sys includes in its offer a wide choice of high purity germanium detectors hpge. Characterization of mechanically cooled high purity. High purity germanium hpge detectors remain the recognized gold standard for highresolution gammaray spectroscopy. The accuracy of beam energy depends solely on the detection results of hpge detector. Position information has been limited to the solid angle and hence size.
Evaluation of erosion and sedimentation rates using the. Hpge detectors are operated in vacuum at liquid nitrogen. The detectors i worked with are referred to as a coaxial ge detectors, high purity ger. Highpurity germanium hpge detectors and spectrometers for gamma analysis, waste management, environmental monitoring, laboratory analysis, insitu measurements, homeland security, health physics, lowbackground measurements. Why high purity germanium hpge radiation detection technology is superior to other detector technologies for isotope identification synopsis. The response of highpurity germanium detectors to xrays.
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. In this configuration, the electric contacts are provided on the two flat surfaces of a germanium crystal. The starting material is bulk germanium intended for the semiconductor industry. High purity germanium detector array spie digital library. Hpge detector were performed in order to determine the parameters of anisotropic mobility for. We characterized the detectors by measuring the leakage current, capacitance, and. Modeling of bege detectors the detector used for the present simulation is a modified thickwindow version of a broad energy germanium bege detector 20, a standard ptype highpurity ge hpge detector offered by canberra semiconductor. In this work, the aim is to improve the technique of get for irradiated nuclear fuel, by developing a detector concept that allows for a higher spatial resolution andor faster interrogation. Germanium detectors are semiconductor diodes having a pin structure in which the intrinsic i region is sensitive to ionizing. Digital gammaray spectroscopy with high purity germanium. 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. 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. 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.
Broad energy germanium detectors bege by canberra mirion technologies, inc. On two cryogenic systems of high purity germanium detector. A prototype high purity germanium detector for high. In these days, gammaray spectroscopy with a high purity germanium hpge detector has been widely used for the activity measurements of natural radionuclides contained in the soil of the earth. High purity germanium hpge is the only radiation detection. The resolution at low energies is equivalent to that of our low ener. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a. Simulation of the response of a segmented highpurity. Di erent variations of ge detectors are available from commercial manufacturers, which have di erent performance characteristics. High purity germanium detector calibration at isolde.
Hyperpure germanium hpge detector fabrication 4 hpge crystal were first developed in the mid 1970s. Highpurity germanium hpge detectors offer the best er of any conventional radiation detector with 1% fwhm at 140 kev johnson et al 2011a. These crystals should not have a net electrically active impurity concentration greater than 10 l0 cm. 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. 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. A 24% intrinsic ptype germanium blindhole coaxial detector was used in this work.
Pdf resolution and efficiency of high purity germanium. Fabrication and characterization of highpurity germanium. Planar configuration an example of a planar hpge detector using a ptype crystal is shown in fig. 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. Germanium detectors are essential instruments in high resolution ray spectroscopy applications. Appendix c truck mounted high purity germanium detector. Pdf the availability of germanium with less than 1010 acceptorscm3 has enabled us to fabricate and study the performance of germanium detectors of. Why high purity germanium hpge radiation detection.
This summer student project involved the test and calibration of two high purity coaxial germanium gammaray detectors. In nuclear physics we require precise knowledge of the energy and time of the interaction of a gammaray photon in a highpurity germanium hpge detector. Operation of a high purity germanium crystal in liquid argon. The first gamma ray spectrometer is the one dimensional high purity germanium spectrometer. We measured full energy peak efficiency of highpurity germanium detector which is important for gammaray spectrometry experiments. We present the working principles of a novel concept for gamma emission tomography using a segmented highpurity germanium hpge detector. The wvalue and energy resolution dependencies on the xray energy have been studied. Signal modeling of highpurity ge detectors with a small.
Index termsneutrinoless double beta decay, gerda, hpge detector, liquid argon. No abrupt variation of wis observed at the germanium k absorptionedge 11. As a result, gammaray spectrometers based on highpurity germanium detectors are emerging as a powerful tool for a range of planetary science applications. High purity germanium detector in gammaray spectrometry. The energy response function also was calculated using monte carlo simulation. The detector is coaxial type p characterized by a high energy a relative efficiency of 30%. Resolution function of a gmx series coaxial detector system model number gmx40p483 in the range of 40 kev to 1. High purity germanium detectors hpge are made from extremely pure ptype or ntype germanium. Measurements of detector material samples with two hpge. The crucial condition for hpge detector functioning properly is. Gaussian energy broadening function of an hpge detector in. Fabrication process development for high purity germanium. 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.
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