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arXiv · 2101.08650

AstroSat-CZTI as a hard X-ray Pulsar Monitor

K. G. Anusree·D. Bhattacharya·A. R. Rao·S. Vadawale·V. Bhalerao·A. Vibhute
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Abstract

The Cadmium Zinc Telluride Imager (CZTI) is an imaging instrument onboard AstroSat. This instrument operates as a nearly open all-sky detector above ~60 keV, making possible long integrations irrespective of the spacecraft pointing. We present a technique based on the AstroSat-CZTI data to explore the hard X-ray characteristics of the $γ$-ray pulsar population. We report highly significant ($\sim 30σ$) detection of hard X-ray (60--380 keV) pulse profile of the Crab pulsar using $\sim$5000 ks of CZTI observations within 5 to 70 degrees of Crab position in the sky, using a custom algorithm developed by us. Using Crab as our test source, we estimate the off-axis sensitivity of the instrument and establish AstroSat-CZTI as a prospective tool in investigating hard X-ray characteristics of $γ$-ray pulsars as faint as 10 mCrab.

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K. G. Anusree, D. Bhattacharya, A. R. Rao, S. Vadawale, V. Bhalerao, A. Vibhute. 2021-02-26. AstroSat-CZTI as a hard X-ray Pulsar Monitor. https://doi.org/10.1007/s12036-021-09707-5

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