Publications (3)0 Total impact
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Article: Near room temperature X-ray and Gamma ray spectroscopic detectors for future space experiments
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ABSTRACT: New generation Cadmium Telluride (CZT & CdTe) solid state detectors can provide high quantum efficiency with reasonably good energy resolution and can operate at near room temperature; an unique advantage for space experiments. We present here results of our study of small diode detectors as well as large area pixel detectors. Our study is aimed at developing near room temperature hard X-ray spectroscopy detectors for ASTROSAT and other future Indian space science missions.We have studied a Si-PIN detector in the energy range 5 - 60 keV and CZT & CdTe Schottky diode detectors in the energy region 10 - 1330 keV. We have studied large area (64 cm$^2$) CZT pixel detectors with pixel size close to the small CZT detector. We have studied individual pixels as well as CZT detector as a whole (summed over all the 1024 pixels). The energy resolution behaviour of the large area CZT detector is similar to that of small diode detectors in the low energy region. The change in operating temperature from room temperature ~20 to ~70$ degree C drastically affects both the energy resolutionas well as the peak area due to a sharp rise in the thermal noise.These results suggest that the cooling of detector system will provide better energy resolution as well as detection efficiency. Comment: 12 Figures07/2005; -
Article: X-Ray Astronomy Experiment On The Indian Satellite Irs-P3
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ABSTRACT: An x-ray astronomy experiment consisting of three collimated proportional counters and an X-ray Sky Monitor (XSM) was flown aboard the Indian Satellite IRS-P3 launched on March 21, 1996 from SHAR range in India. The Satellite is in a circular orbit of 830 km altitude with an orbital inclination of 98 ffi and has three axis stabilized pointing capability. Each pointed-mode Proportional Counter (PPC) is a multilayer, multianode unit filled with P10 gas (90% Ar + 10% CH 4 ) at 800 torr and having an aluminized mylar window of 25 micron thickness. The three PPCs are identical and have a field of view of 2 ffi Theta2 ffi defined by silver coated aluminium honeycomb collimators. The total effective area of the three PPCs is about 1200 cm 2 . The PPCs are sensitive in 2-20 keV band. The XSM consists of a pin-hole of 1 cm 2 area placed 16 cm above the anode plane of a 32 cmTheta 32 cm position sensitive proportional counter sensitive in 3-8 keV interval. The position of the x-ray e...04/1997; -
Article: Near room temperature X-ray and γ-ray spectroscopic detectors for future space experiments
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ABSTRACT: New generation Cadmium Telluride (CZT and CdTe) solid-state detectors can provide high quantum efficiency with reasonably good energy resolution and can operate at near room temperature; a unique advantage for space experiments. We present here results of our study of small diode detectors as well as large area pixel detectors. Our study is aimed at developing near room temperature hard X-ray spectroscopy detectors for ASTROSAT and other future Indian space science missions. We have studied a Si-PIN detector in the energy range 5–60 keV and CZT and CdTe Schottky diode detectors in the energy region 10–1330 keV. Our results suggest that the energy resolution is limited by the thermal/electronic noise in the low-energy region while it is affected by the charge transport properties of the detector in the higher energy region . We have studied large area CZT pixel detectors with pixel size close to the small CZT detector. We have studied individual pixels as well as CZT detector as a whole (summed over all the 1024 pixels). The CZT pixel detectors are single carrier detectors with peaking time . The energy resolution behaviour of the large area CZT detector is similar to that of small diode detectors in the low-energy region. The change in operating temperature from room temperature ∼20 to drastically affects both the energy resolution as well as the peak area due to a sharp rise in the thermal noise. These results suggest that the cooling of detector system will provide better energy resolution as well as detection efficiency. Our results also show that the crystal uniformity is another important issue in the case of large area CZT pixel detectors.Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
