Instruments of RT-2 Experiment onboard CORONAS-PHOTON and their test and evaluation I: Ground calibration of RT-2/S and RT-2/G

Dipak Debnath; Anuj Nandi; A. R. Rao; J. P. Malkar; M. K. Hingar; T. B. Kotoch; S. Sreekumar; V. P. Madhav; Sandip K. Chakrabarti

doi:10.1007/s10686-010-9205-2

arXiv · 1011.3326

Instruments of RT-2 Experiment onboard CORONAS-PHOTON and their test and evaluation I: Ground calibration of RT-2/S and RT-2/G

Dipak Debnath·Anuj Nandi·A. R. Rao·J. P. Malkar·M. K. Hingar·T. B. Kotoch·S. Sreekumar·V. P. Madhav·Sandip K. Chakrabarti

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Abstract

Phoswich detectors (RT-2/S & RT-2/G) are major scientific payloads of the RT-2 Experiment onboard the CORONAS-PHOTON mission, which was launched into a polar Low Earth Orbit of around 550 km on 2009 January 30. These RT-2 instruments are designed and developed to observe solar flares in hard X-rays and to understand the energy transport processes associated with these flares. Apart from this, these instruments are capable of observing Gamma Ray Bursts (GRBs) and Cosmic diffuse X-ray background (CDXRB). Both detectors consist of identical NaI(Tl) and CsI(Na) scintillation crystals in a Phoswich combination, having the same diameter (116 mm) but different thicknesses. The normal working energy range is from 15 keV to 150 keV, but may be extendable up to ~ 1 MeV. In this paper, we present the RT-2/S and RT-2/G instruments and discuss their testing and calibration results. We used different radio-active sources to calibrate both detectors. The radio-active source Co^57 (122 keV) is used for onboard calibration of both instruments. During its lifetime (~ 3-5 years), RT-2 is expected to cover the peak of the 24th solar cycle.

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Dipak Debnath, Anuj Nandi, A. R. Rao, J. P. Malkar, M. K. Hingar, T. B. Kotoch, S. Sreekumar, V. P. Madhav, Sandip K. Chakrabarti. 2010-11-15. Instruments of RT-2 Experiment onboard CORONAS-PHOTON and their test and evaluation I: Ground calibration of RT-2/S and RT-2/G. https://doi.org/10.1007/s10686-010-9205-2

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