The calculation of electrostatic potentials and fields in a highpurity germanium hpge detector is the initial step in a full pulseshape simulation 1,2,3,4,5 process. Hpge detector fullenergy peak efficiency calculation for inhomogeneously activated samples lojze gac. Hpge detectors timing using pulse shape analysis techniques. The majority of gamma spectroscopy applications such as those found in counting.
Reliability of the generic hpge detector characterization. In accordance with manufacturer datasheet, the detector has a germanium crystal with 67. Linear mechanism to open and close the lids of the hpge detector. Determination of the photopeak detection efficiency of a.
The main purpose of this paper is to validate the generic detector characterization for an hpge detector falcon 5000 companion to isocs software, to explore the possibilities of combining gamma counting system with isocs software calculations to improve the absolute measurement of nm samples i. Profile hpge photon detector product configuration guide. Like its falcon 5000 predecessor, it offers many stateoftheart features, such as a thermalcycle free cryostat, an integrated allinone design and laboratorygrade energy resolution. The detector element is held in place by a holder, which is electrically isolated from but thermally connected to a copper cold finger. Due to a larger diameter crystal, at 122 kev, the sseries. Calculation of coincidence summing correction factors for. Cross section diagram of hpge detector with liquid nitrogen reservoir 32 figure 2.
Characterisation of an ultra lowbackground point contact hpge well. The path length through the detector, l, is a function of r and the detector shape. H hpge detector apparatus viii i raw gammaray spectra ix references ix 2. This volume contains the operating manuals for four related programs, each separated by a blue divider. Metal detector is a device that can detect metal, the basics can make a sound when it is near some metal, and the more advanced can tell what kin of metal and how deep it is down, they are using different detecting principles. Workshop on basic radiation detection and simulation with. Gammaw performs fullyautomated peak search, or allows users to define tentative or wellknown peak positions calc activates analysis of defined roi or spectrum range. The high purity germanium detectors hpge complete set is composed by the following components. Figure 1 illustrates the various detector geometries that are available from. Portable hpge detector is designed for detection, accumulation and processing of gamma spectra in field and industry conditions where small dimensions and weight of spectrometer are important.
Determination of the photopeak detection efficiency of a hpge detector, for volume sources, via monte carlo simulations by raphael wesley damon dissertation submitted in fulfilment of the requirements for the master of science degree in physics at the university of the western cape july 2005 supervisors. Multielement readout of structured hpgedetectors for. The majority of gamma spectroscopy applications such as those found in counting laboratories involve the energy range 40 kev upward. Pdf the photopeak efficiency, the peak to valley ratio, the energy resolution and the minimum detectable activity of a hpge detector were. Due to its high energy resolution and efficiency, hpge detectors are also. The purpose of this thesis is to assemble a hpge detector intended to be used in a mass experiment. Characterization of an hpge detector for experiments. Wilkerson physics the observation of neutrinoless doublebeta decay 0 would prove the majorana nature of the neutrino and show the nonconservation of lepton number. The spectrometers are used for radionuclide analysis and for monitoring of activity in the nuclear industry and related environment monitoring.
We got the assignment to built a detector there could detect a 10kr coin at 5cm. Additionally, it requires the use of a peltier cooler to cool an internal infrared shield10. This is the first portable hpge gamma spectrometer on the market where there is a choice of multiple 6 detector and cryostat options. Germanium detectors have been in use for more than. Germanium hpge detector detector efficiencye the detector efficiency in eq. Rittersdorf gamma ray spectroscopy 1 abstract in lab, a total of eight spectra were measured. Because high purity germanium detectors hpge has relatively low band gap, these detectors must be cooled down. Profile hpge photon detector product configuration guide figure 3 reinforces the marked improvement in efficiency for the profile s detectors when measuring a filter paper onendcap source. Determination of the photopeak detection efficiency of a hpge. The automated hpge spectrometer is a fully automated systems with a robotic sample changer enabling the user to measure up to 40 samples, without having to interact with the automated spectrometer. This is a pdf file of an unedited manuscript that has been accepted for. A set of time aligned signals was acquired in a coincidence measurement using a coaxial hpge and a ceriumdoped lanthanum chloride lacl 3. Germanium detectors are semiconductor diodes having a pin structure in. Pdf autohpge, an autosampler for gammaray spectroscopy.
Highpurity germanium hpge handheld radiological isotope. A large hpge detector for the nondestructive radioassay. From know values of gammaray energies, a calibration curve was plotted. Weak alpha sources available without a specific nrc. Hpge detector, gamma spectrometry, low background, montecarlo simulation, photomultiplier tube. 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. Liquid nitrogen ln 2 or electromechanical cooling system are both available. This driven inner shield reduces the radiative heat load of the hpge detector element. The purpose of an hpge detector is to convert gamma rays into electrical impulses which can. Compton suppressors or anticompton shields acs are used to suppress unwanted background in gamma spectrometry performed with ge detectors. Calibration of hpge gammaray planar detector system for. Measurements on a 12fold segmented, ntype, large volume, irregular shaped hpge detector were performed in order to determine the parameters of anisotropic mobility for electrons and holes as charge carriers created by. Calculation of full energy peak efficiency for hpge. Samples are presented via t he internal volume within the centre of the detector source.
Falcon 5000 portable hpgebased radionuclide identifier. Compton suppressors, anticompton shields acs berkeley. Fadhil department of astronomy and space, college of science, university of baghdad, baghdad, iraq abstract this research presents results on the full energy peak efficiency of a high purity. Experimental measurements were taken using an hpge detector. Gem series coaxial hpge detector product configuration guide. The canberra bege detector offers a clear advantage over more conventional hpge configurations, by minimizing the low energy loss and thereby enhancing the efficiency and resolution at low energy while still preserving good efficiency at higher energies. The sensitive detector surfaces are thus protected from moisture and other contaminants.
The standard crystal offering is a large 40% coaxial crystal featuring excellent. Pdf a simple method for the characterization of hpge detectors. The cold finger transfers heat from the detector assembly to the liquid nitrogen reservoir. Hpgedetector with 32 strips 1 mm x 5 mm each hpgedetector with 8 elements 3.
A human being in a bioassay measurement is a fixedformat sample. A photograph of the hpge detector with accompanying lead castle used by the erl 33 figure 2. This data, which may be trended over time, allows the user to take preventative. Calculation of full energy peak efficiency for hpge detector using monte carlo method alaa b. Delhi, both single crystal hpge detectors and composite. Gammaw gammaray analysis software for hpge detectors. Hpge and clover gamma ray detector maintenance cern. The transmission probability for an unscattered photon is given by the following product. Detective x algorithms beyond the intrinsic selectivity of the hpge detector type, the ultimate performance in terms of the detective x fidelity of identification depends on the software algorithms. An integrated digital backend makes use of the detector sensors to continuously monitor and store all relevant parameters and status information. Hpge detectors abstract in this work the pulse shape analysis has been used to improve the time resolution of high purity germanium hpge detectors. This detector was an ortec gmx series hpge coaxial detector system with a relative efficiency of 40% at 1.
Hpge detector, for volume sources, via monte carlo. The purpose of an hpge detector is to convert gamma rays into electrical impulses which can be used, with. S8530 has significantly higher absolute efficiency at all energies below 1 mev down to 10 kev. To characterize the electron mobility the complete outer detector surface was scanned in small steps employing photopeak interactions at 60 kev. Here are a series of experiments involving alpha particle transmutation of light elements and detection of the resulting gamma radiation signatures.
To connect the diode to an electrical circuit to amplify the. If the efficiency curve at low energy region is important, selecting proper. Hpge detector fullenergy peak efficiency calculation for. Benchmark hpge detector measurements gamma rays following beta decay i common gammaray sources i na22. Combining these properties in one detector is unique to canberras bege detector. High purity germanium detector calibration at isolde. The cryo3 also suffers from poor energy resolution with measured values of 3. Ortec licensed the original lawrence livermore radscout algorithm in 2003 and has made numerous improvements to it over the years. The aegis portable hpge spectrometer is the newest transportable, batterypowered hpge gamma spectrometer in mirions portfolio. Alpha backgrounds and their implications for neutrinoless doublebeta decay experiments using hpge detectors roberta.
It is also used to guide the design of novel detector geometries to avoid unreasonably high depletion voltages or hidden undepleted regions, which may occur when the size of a detector is enlarged. This special downloads page is to be used to host files that might be requested from time to time, but are not made generally available. The detector holder is held in place by an antimicrophonic stabilizer. It could effectively predict the efficiency of a detector at any sourcetodetector distance. Experimental efficiency calibration of a hpge detector 100 cm 3 for a point source at 12 cm between 10 and 1500 kev linear scale energy kev 0 200 400 600 800 1200 1400 1600 1800 efficiency % 0. A highpurity germanium hpge detector is the ultimate instrument for energy spectrometry of gamma radiation. No particle accelerators, no vacuum environment, no dangerous and specificallylicensed. If there is evidence of shipping damage contact the carrier, file a claim for. The detection of low intensity gamma ray lines is complicated in spectrometry performed with high purity germanium hpge detectors by the presence of compton scattered gamma rays of higher energies. Two different singlesided structured hpgedetectors have been tested. This reliable robotic sample changer increases the productivity and reduces the possibility of health risks hpge systems hpge all in one. Hpge detector field calculation methods demonstrated with. The purpose of an hpge detector is to convert gamma rays into electrical impulses which can be used, with suitable signal processing, to determine their energy and intensity. Coaxial hpge detector with lead shield is used to measure the specific gamma radiation of radionuclides from various types of environmental objects such as rocks, minerals, sludge, slag, soil, plant, sediment and particulate matter in air and water.
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. Pdf studying of characteristics of the hpge detector for. Part 1 the genie 2000 operations manual, including the s501 gamma analysis. Gem series coaxial hpge detector product configuration guide ptype coaxial hpge detectors for high performance gamma spectroscopy in the energy range of 40 kev and up. Reference standard sources which cover the energy range are important for efficiency calibration. The detector is mounted in a vacuum chamber which is attached to or inserted into a ln 2 dewar. Highpurity germanium hpge handheld radiological isotope identification devices request for multiple jurisdictions in the national capital region the national capitol region ncr is committed to preserving life and promoting health and safety through prehospital treatment and.
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