NSSDCA ID: 1972-091A-01
Mission Name: SAS-BThe instrument consisted of two spark-chamber assemblies, four plastic scintillation counters, four Cerenkov counters, and an anticoincidence scintillation counter dome assembled to form a telescope. The spark chamber assembly consisted of 16-wire spark-chamber modules with a magnetic core readout system. Sandwiched between these two assemblies was a plane of plastic scintillator formed by the four scintillation counters. Thin tungsten plates, averaging 0.010-cm thick, were interleaved between the spark chamber modules, which had an active area of 640 sq cm. These plates provided the material for the gamma ray to convert into an electron-positron pair and provided a means of determining the energy of these particles by measuring their coulomb scattering. The spark chamber modules revealed the position and direction of the particles; from this information, the energy and direction of the gamma ray was determined. The scintillation counters and the four directional Cerenkov counters that were placed below the second spark chamber assembly constituted four independent counter coincidence systems. The single-piece plastic scintillator dome surrounded the whole assembly except at the bottom to discriminate against charged particles. The threshold of the instrument was about 30 MeV, and energies up to about 200 MeV could be measured along with the integral flux above 200 MeV. The angular resolution of the telescope varied as a function of energy and arrival direction from 1.5 to 5 deg. During the lifetime of the experiment from November 15, 1972, to June 8, 1973, approximately 55% of the celestial sphere, including most of the galactic plane, was surveyed.
Mass: 79 kg
Power (avg): 5 W
Bit rate (avg): 2 kbps
Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Carl E. Fichtel | Principal Investigator | NASA Goddard Space Flight Center | fichtel@lheavx.gsfc.nasa.gov |