HEAO‐2 x‐ray spectra study plasmas
DOI: 10.1063/1.2914429
The Einstein Observatory satellite has been orbiting the Earth at an altitude of 300 miles since November 1978, with an x‐ray telescope comparable to large optical telescopes in resolution and sensitivity. Among the various on‐board detectors that examine the x‐ray images produced in the focal plane of this 58‐centimeter telescope is a Bragg crystal spectrometer that makes possible for the first time detailed study of x‐ray spectral lines from sources outside the solar system. This high‐resolution xray spectrometer, developed by Claude Canizares, George Clark and their colleagues at MIT, permits one now to investigate hot gases in distant supernova remnants and clusters of galaxies with the same diagnostic techniques that have been applied to plasmas in the laboratory and in the solar corona for decades.
