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The Cadmium-Zinc-Telluride Imager (CZTI) is one of the four X-ray instruments onboard AstroSat. CZTI equipped with a Coded Aperture Mask  has the following salient features:

  • High stopping power, low thermal noise and room temperature operation,
  • Excellent energy and spatial resolution,
  • Low background,
  • Unmatched broadband (0.3 - 100 keV) capability when CZTI is combined with two other instruments SXT and LAXPC onboard AstroSat.


CZTI provides crucial hard X-ray data for wide band X-ray spectroscopic observations of X-ray binaries, AGNs and other bright X-ray sources. Background suppression using a veto detector, background measurement using a Coded Aperture Mask, continuous calibration using an alpha-tagged X-ray source are some of the features of this payload. Time tagged individual photon data on a continuous basis provides an excellent opportunity to understand and correct  the systematic errors in the spectral data.