The MicroGe detector is a compact electrically cooled, fanless, lightweight High Purity Germanium detector (HPGe). With a short cooling time, this state-of-the …
OBJECTIVES. PHDs Co. is developing mechanically cooled detector systems for large volume germanium detectors (~ 570 cm3, ~ 3 kg, ~ 140 %, or larger) for field use in rugged conditions. A new generation of Stirling-cycle mechanical cooler is being used to reliably cool the very largest germanium detectors while requiring no maintenance.
2. Electrically Cooled Germanium System First electrically cooled HPGe detectors appeared on the market about 20 years ago, but were rather big and heavy and could not be used as portable NDA instrument that time. However, the technology has being improved and several years ago a new generation of portable electrically cooled HPGe …
Journal Article: Ultra-low noise mechanically cooled germanium detector Ultra-low noise mechanically cooled germanium detector. Full Record; Other Related Research Related Research
in high-purity germanium detectors. In this fully automated setup, the detector under test is irradiated from the top with 661.660keV gammas, some of which Compton scatter inside the detector. The interaction points in the detector can be reconstructed when the scattered gammas are detected with a pixelated camera placed at the side of the ...
germanium detectors for field use in rugged conditions. The hand-held "Detective" is an elegant example of a currently available mechanically cooled germanium detector system manufactured by Ortec (Keyser et al., 2003). This system uses a small Stirling-cycle cooler to cool a modest sized germanium detector to operating temperature
In this paper, methods are presented which can lower the electronic noise of these detectors. Through ultra-low vibration mechanical cooling and wire bonding of a …
The FRIS system uses an electrochemically cooled germanium detector and its own analysis software to detect and identify special nuclear material and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that …
The ultra-low noise germanium test stand developed herein presents a unique and important opportunity for the study of fundamental physics of high purity germanium detectors and low noise electronics over a broad range of temperatures. Charge carrier mobility and leakage currents both improve at lower temperatures.
Because germanium has a relatively low band gap, these detectors must be cooled in order to reduce the thermal generation of charge carriers (thus reverse leakage current) …
Parts of HPGe Detectors. The major drawback of germanium detectors is that they must be cooled to liquid nitrogen temperatures. Because germanium has a relatively low band gap, these detectors must be …
The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (GErmanium MINIature spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. ... The other is a 2000 mm/sup 2/ planar intrinsic germanium detector housed in an end …
Mechanical cooling of germanium detectors has historically been a difficult endeavor. The success or failure of mechanically cooled germanium detectors stems from three main …
CURRENT HPGe DSSD DESIGN & PERFORMANCE. 90 mm diameter, 10 mm thick. 55 cm2 active area. 16 x 16 orthogonal strips. 5 mm strip pitch (0.25 mm gaps) Mechanically cooled (75-85 K) Position Estimation. Sub-Strip interpolation. 530 μm x 530 μm pixel size.
Conclusions. LLNL has successfully developed a portable, electromechanically cooled high purity germanium radiation detector system. Prototype systems have been extensively field tested in a variety of applications including those requiring operation in harsh environments. The ability to operate from a single +12 V …
cooled cryostat uses a CFC-free refrigerant and is well suited for use in industrial and laboratory applications. 5 10 20 50 100 200 500 1000 2000 10.0 1.0 0.1 ... Germanium Detectors Pulsed-Optical Reset preamplifiers are widely used on low energy detectors where resolution is of utmost consideration. Eliminating the feedback
We have successfully developed and fielded an electromechanically cooled germanium radiation detector (EMC-HPGe) at Lawrence Livermore National Laboratory (LLNL). This detector system was designed to provide optimum energy resolution, long lifetime, and extremely reliable operation for unattended and portable applications.
The MicroGe detector is a compact electrically cooled, fanless, lightweight High Purity Germanium detector (HPGe). With a short cooling time, this state-of-the-art detector opens the possibility to do spectroscopic measurement in less than 30 minutes while keeping the benefits of a laboratory grade detector.
High-purity germanium (HPGe) is a vibration-sensitive, high-resolution detector. It has been found that microphonic noise induced by vibration and electromagnetic interference from EMC causes energy …
of Mechanically Cooled High Purity Germanium (HPGe) Detectors at Elevated Temperatures." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Nuclear Engineering.
When germanium detectors are cooled with an electro-mechanical cooler, such as the ICS-P4 Integrated Cryocooling System for PopTop HPGe Detectors from ORTEC, there is a small possibility of an AC power failure causing detector damage. The supposed mechanism is that following the power failure, the system starts warming toward room …
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 …
the LN2 surrounding the detector array. In this configura-tion, the germanium detectors are directly cooled to a stable operating temperature by the LN2. Each detector string in CDEX-10 contains 3 point-contact germanium detectors denoted as Ge1-Ge3 from bottom to top, as shown in Figure 1. Each germanium crystal is ap-
Lawrence Livermore National Laboratory (LLNL) is replacing a liquid nitrogen cooled high purity germanium detection system with an electrically cooled high purity germanium system for its scanning bed whole body counting system. The new detectors offer a safer environment for workers while they are measured inside the shielded facility …
We have integrated a small, highly-reliable, electro-mechanical cryo-cooler with a high-resolution germanium detector for portable/field applications. The system weighs 6.8 kg and requires 40 watts of power to operate once the detector is cooled to its operating temperature. the detector is a 500 mm {sup 2} by 20-mm thick low-energy ...
Deciphering Radiation Alarms: Using High Purity Germanium Detectors for Nuclear Security; ... The need to keep the detector cooled, the comparatively high purchase and maintenance costs, and the required scientific expertise to interpret the data for security and safety purposes, present an impediment to widespread …
Parts of HPGe Detectors. The major drawback of germanium detectors is that they must be cooled to liquid nitrogen temperatures. Because germanium has relatively low band gap, these detectors must be cooled in order to reduce the thermal generation of charge carriers to an acceptable level. Otherwise, leakage current induced …
The RASA detector system will benefit from the availability of such detectors (Bowyer et al., 1997; Miley et al., 1998). Mechanical cooling of germanium detectors has historically been a difficult endeavor. The success or failure of mechanically cooled germanium detector systems arises from three main technical issues: temperature, vacuum, and
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. Otherwise, leakage current induced noise destroys the energy resolution of the detector.
The BEGe detector represents a breakthrough in this respect. The BEGe unit is designed with an electrode structure that enhances low energy resolution and is fabricated from select germanium having an impurity profile that improves charge collection (thus resolution and peak shape) at high energies. Indeed, this ensures good resolution and peak ...
measured by using Hall Effect. Two different geometries of planar detectors were designed as shown in Figure 1. The thickness of their grooves and wings are fixed at 1.5 mm and 2 mm, respectively. The fabrication process is the same for the detectors with different geometries. Figure 1. Schematic of detector geometries for top view and cross ...
The Compex detector is an electrically cooled, composite germanium detector that uses four coaxial, cubic-shaped, single-encapsulated germanium crystals. …
2. Methods. All measurements were performed using a mechanically-cooled HPGe detector from PHDs Co. (Knoxville, TN, USA). This double-sided strip detector was fabricated from a germanium crystal 90 mm in diameter and 10 mm thick using amorphous-semiconductor contacts (Hansen and Haller, 1977; Luke et al., 1992; Luke et al., …
First, excessive vibrations from conventional mechanical cooling (30–80 K) would significantly degrade the performance of low noise germanium detectors. Boiling liquid cryogens also cause microphonics which limit low noise performance at longer peaking times. Our detector system operated down to 30 K and eliminated microphonics …
mechanically cooled germanium detectors stems from three main technical issues: temperature, vacuum, and vibration. These factors affect one another. A detailed analysis of these factors and their effects on detector performance was recorded last year (Hull et al., 2006). These factors are being studied in the laboratory at the most
Germanium, due to its characteristics such as a narrow bandgap, high electron mobility, and high energy resolution, has emerged as an ideal material to produce various types of detectors [1,2,3].It has found widespread applications in fields such as nuclear physics, dark matter detection, and medical imaging [4,5,6,7,8].High-purity …
resolution germanium detector for portable/field applications. The system weighs 6.8 kg and requires 40 watts of power to operate once the detector is cooled to its operating temperature. The detector is a 500 mm* by 20-mm thick low-energy configuration that gives a full-width at half maximum (FWHM) energy resolution of 523 eV at 122 keV,
One of the particularities of the HPGe detector is the need to be cryo-cooled to limit the leakage current of the germanium sensor. This condition leads to a complex detector layout as schematically illustrated with Fig. 1. The detector consists of three main blocks: ... To cope with high segmented and compact germanium detector, operating in …