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AstroSat-CZTI as a hard X-ray Pulsar Monitor

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 نشر من قبل K. G. Anusree
 تاريخ النشر 2021
  مجال البحث فيزياء
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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 $gamma$-ray pulsar population. We report highly significant ($sim 30sigma$) 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 $gamma$-ray pulsars as faint as 10 mCrab.



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