POSITION-SENSITIVE DETECTORS IN X-RAY ASTRONOMY

Detectors for X-ray astronomy include gas filled proportional and scintillation counters, microchannel plates, CCDs and single photon microcalorimeters. The spatial and nondispersive spectral resolutions of all of these systems are compared in the light of present requirements. The current state of development in each of the four areas is then discussed and the salient features of each system evaluated. While the subject has seen gas filled detectors employed from the beginning, the need for improved spectral resolution combined with high quantum efficiency is leading to an increased emphasis on solid state detectors in spite of the difficulties involved in cooling these systems in orbit. Microchannel plates remain important at photon energies less than 1 keV because of their excellent spatial resolution.