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arXiv · 1710.10773

Cadmium Zinc Telluride Imager onboard AstroSat : a multi-faceted hard X-ray instrument

A. R. Rao·D. Bhattacharya·V. B. Bhalerao·S. V. Vadawale·S. Sreekumar
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Abstract

The AstroSat satellite is designed to make multi-waveband observations of astronomical sources and the Cadmium Zinc Telluride Imager (CZTI) instrument of AstroSat covers the hard X-ray band. CZTI has a large area position sensitive hard X-ray detector equipped with a Coded Aperture Mask, thus enabling simultaneous background measurement. Ability to record simultaneous detection of ionizing interactions in multiple detector elements is a special feature of the instrument and this is exploited to provide polarization information in the 100 - 380 keV region. CZTI provides sensitive spectroscopic measurements in the 20 - 100 keV region, and acts as an all sky hard X-ray monitor and polarimeter above 100 keV. During the first year of operation, CZTI has recorded several gamma-ray bursts, measured the phase resolved hard X-ray polarization of the Crab pulsar, and the hard X-ray spectra of many bright Galactic X-ray binaries. The excellent timing capability of the instrument has been demonstrated with simultaneous observation of the Crab pulsar with radio telescopes like GMRT and Ooty radio telescope.

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A. R. Rao, D. Bhattacharya, V. B. Bhalerao, S. V. Vadawale, S. Sreekumar. 2017-10-30. Cadmium Zinc Telluride Imager onboard AstroSat : a multi-faceted hard X-ray instrument. https://doi.org/10.18520/cs%2Fv113%2Fi04%2F595-598

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