The Gas Scintillation Proportional Counter on EXOSAT

The inclusion of a gas scintillation proportional counter (GSPC) within the EXOSAT payload complement significantly improves the spectroscopic capability of the mission. This broad-band medium energy spectrometer used in conjunction with the large area proportioni counter array (ME) should provide additional spectroscopic details on strong X-ray sources at photon energies above ~ 2 keV. The novel type of detector has an energy resolution at least a factor of two better than the ME experiment over a similar bandwidth (2 – 40 keV).