Title: Large Area X-ray Proportional Counter (LAXPC) Instrument on AstroSat,
Abstract: Large Area X-ray Proportional Counter (LAXPC) is one of the major AstroSat
payloads. LAXPC instrument will provide high time resolution X-ray observations
in 3 to 80 keV energy band with moderate energy resolution. A cluster of three
co-aligned identical LAXPC detectors is used in AstroSat to provide large
collection area of more than 6000 cm2 . The large detection volume (15 cm
depth) filled with xenon gas at about 2 atmosphere pressure, results in
detection efficiency greater than 50%, above 30 keV. With its broad energy
range and fine time resolution (10 microsecond), LAXPC instrument is well
suited for timing and spectral studies of a wide variety of known and transient
X-ray sources in the sky. We have done extensive calibration of all LAXPC
detectors using radioactive sources as well as GEANT4 simulation of LAXPC
detectors. We describe in brief some of the results obtained during the payload
verification phase along with LXAPC capabilities.