The COS-B experiment for gamma-ray astronomy.

The COS-B satellite will carry a single large experiment, capable of detecting gamma-rays with energies in excess of 20 MeV in order to study in detail the sources of extraterrestrial gamma radiation. The principal objectives of the study will be to investigate the angular structure of gamma-ray emission from the galactic plane, to measure the flux of the isotropic radiation from high galactic latitudes believed to be of extra-galactic origin, to examine known or postulated point sources of the radiation and to determine the energy spectra of all identified sources. The experiment features a 16-gap spark chamber for the identification and determination of the arrival direction of the gamma quanta, a caesium-iodide energy calorimeter for energy determination, a telescope defining the field of view of the experiment, and a plastic-scintillator anticoincidence shield for the rejection of charged particles. Also included is a proportional counter sensitive to X rays in the 2-12 keV range, to synchronize on the possible short period pulsations of gamma-ray emission from sources detected to pulsate at X-ray wavelengths.