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تسجيل مستخدم جديدProtoEXIST: Advanced Prototype CZT Coded Aperture Telescopes for EXIST
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{it ProtoEXIST1} is a pathfinder for the {it EXIST-HET}, a coded aperture hard X-ray telescope with a 4.5 m$^2$ CZT detector plane a 90$times$70 degree field of view to be flown as the primary instrument on the {it EXIST} mission and is intended to monitor the full sky every 3 h in an effort to locate GRBs and other high energy transients. {it ProtoEXIST1} consists of a 256 cm$^2$ tiled CZT detector plane containing 4096 pixels composed of an 8$times$8 array of individual 1.95 cm $times$ 1.95 cm $times$ 0.5 cm CZT detector modules each with a 8 $times$ 8 pixilated anode configured as a coded aperture telescope with a fully coded $10^circtimes10^circ$ field of view employing passive side shielding and an active CsI anti-coincidence rear shield, recently completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009. During the duration of its 6 hour flight on-board calibration of the detector plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along with the simultaneous measurement of the background spectrum and an observation of Cygnus X-1. Here we recount the events of the flight and report on the detector performance in a near space environment. We also briefly discuss {it ProtoEXIST2}: the next stage of detector development which employs the {it NuSTAR} ASIC enabling finer (32$times$32) anode pixilation. When completed {it ProtoEXIST2} will consist of a 256 cm$^2$ tiled array and be flown simultaneously with the ProtoEXIST1 telescope.
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