PROFILE Series GEM P-Type HPGe Coaxial Radiation Detectors
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PROFILE HPGe Photon Detector Product Configuration Guide • "Application-Matched" P-type HPGe Detectors, optimized for specific sample types, gamma energy ranges and measurement geometries. • Know how your new HPGe detector will perform before you buy it! • Best absolute efficiency for the given IEEE standard relative efficiency in your counting geometry. • Stable thin front contact, no front dead layer growth if stored warm (PROFILE GEM S, SP, and C Series). • Warranted crystal dimensions ensure measurement performance. • Reproducible dimensions mean reproducible performance. . . no surprises. • Full range of PopTop Cryostats and options. The ORTEC PROFILE Series of P-type High Purity Germanium (HPGe) detectors offers specific crystal dimensions from which you can choose the best solution in YOUR application. Nominal relative efficiency specifications are provided to help relate relative efficiency to terms of crystal dimensions. The resolution is measured according to the IEEE standard. If a particular PROFILE series detector is available from the ORTEC detector stocklist, then the ACTUAL MEASURED specifications may be inspected before purchase. F-Series PROFILE GEM Detectors F-Series PROFILE detectors employ "over-square" (diameter > length) structures. This crystal geometry is often referred to as semi-planar structure. For a given relative (IEEE) efficiency, the F-Series represents the "best use" of germanium material producing the maximum absolute counting efficiency for on-endcap or "close geometry" extended samples, such as: • Point sources on-endcap • Filter paper samples on-endcap • Samples presented in bottles and pots on-endcap • Bio-assay applications (e.g., lung monitoring) • Waste drum monitoring Figure 1. GEM and PROFILE P-type HPGe crystal geometries. In addition, the over-square geometry helps improve (lowers) low-energy resolution by reduced crystal capacitance as compared to coaxial crystal geometry. S-Series PROFILE GEM Detectors • All the advantages of the F-Series PROFILE detector with an ultra-thin, stable entrance window. • Excellent warranted performance. • Excellent sensitivity down to 3 keV energy. • No dead layer growth (change in efficiency) from the front of the crystal due to prolonged warm storage. S-Series PROFILE GEM detectors have a semi-planar crystal geometry and employ a proprietary ultra-thin, stable entrance window to improve low energy efficiency. The S-Series entrance window extends the useful energy range down to 3 keV, while maintaining the excellent peak shape and resolution characteristics of the PROFILE series. Figure 2. Absolute Efficiency vs. Energy for S10530, S9430, S8530, Figure 2 shows the extensive improvement in efficiency at lower energies for a PROFILE “S” GEM50 and GMX50 detectors for a Point Source positioned 25 cm away from the front of the endcap. detector when measuring a point source. Calculated (color) curves show absolute efficiency versus energy for a point source positioned 25 cm from the detector endcap. The S8530 (light green) S-Series detector’s absolute efficiency is significantly higher between 10 keV and 600 keV when compared to the same 50% relative efficiency coaxial P- and N-type detectors. At 59 keV, the 85 mm crystal diameter S-Series detector is nearly 6X more efficient than a P-type coaxial detector (GEM50) (red) and almost 2X more efficient than a coaxial N-type (GMX50) (blue) low-energy detector due to its greater front surface area. As expected, curves converge at 1332 keV, where relative efficiency is measured. The S9430 (green) and S10530 (dark green) unique detectors with 94 mm and 105 mm crystal diameter respectively, further improve absolute efficiencies below

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 on-endcap source. Calculated (color) curves show absolute efficiency versus energy for a 100 mm diameter filter paper source positioned on the detector endcap. The S8530 (light green) has significantly higher absolute efficiency at all energies below 1 MeV down to 10 keV. Due to a larger diameter crystal, at 122 keV, Figure 3. Absolute Efficiency vs. Energy for S10530, S9430, the S-Series detector is 1.9X more S8530,...

PROFILE HPGe Photon Detector Product Configuration Guide The resolution improvement above the S-Series is illustrated in Figure 7 where two peaks from an 55Fe point source positioned 25 cm away from the front of the endcap are overlaid. The full width half max (FWHM) resolution at 5.9 keV energy for the SP8530 is 25% lower as compared to the same diameter and thickness S8530 detector. The 5.9 and 6.5 keV peaks measured with the SP8530 detector (shown in blue) are clearly separated, while the S8530 (shown in red) has more peak overlap. Figure 8 shows 10% improvement in resolution for the...

M-Series PROFILE GEM Detectors The M-Series detectors are designed for use with Marinelli beakers to provide an optimum solution and efficiency. M-Series detectors provide the same resolution and better absolute efficiency (below 50 keV) than GEM series detectors, and better resolution but lower absolute efficiency (below 50 keV) than GMX series detectors. These are made where the endcap diameter is "filled with the crystal" and the length is slightly longer than the diameter. The overall absolute efficiency for a Marinelli beaker is maximized. This is the most common beaker where the well...

PROFILE HPGe Photon Detector Product Configuration Guide The Following Specifications are Provided for Each PROFILE Series Detector • Energy resolution at 1.33 MeV photons from 60Co at optimum shaping time. • Active dimensions. • Nominal values for relative efficiency are given (not a specification). • Peak-to-Compton ratio for 60Co 1.33 MeV peak. • Nominal values for peak shape ratio for the full-width tenth-maximum to the full-width half-maximum for 60Co 1.33 MeV peak are given (not a specification). • Energy resolution at 122 keV photons from 57Co at optimum shaping time for the GEM-F,...