NSSDCA ID: 1980-014A-07
Mission Name: SMMThe gamma-ray spectrometer (GRE) utilized a set of NaI(Tl) detectors and CsI(Na) detectors to form three separate instruments for measurement of the solar gamma-ray spectrum: (1) an actively shielded, multicrystal gamma-ray spectrometer, (2) a high-energy gamma-ray detector, and (3) an auxiliary X-ray detector. The heart of the gamma-ray spectrometer consisted of seven 7.6-sq-cm NaI integral line detectors shielded by an annulus of CsI and a 7.6-cm thick CsI back; the front and back of this system were shielded by a plastic scintillator to reject charged particles. The spectrometer produced a 476-channel pulse-height spectrum every 16 s over the energy range 0.3 to 9 MeV. The energy resolution was less than 7% FWHM at 0.662 MeV. A 2-s time resolution was available in three windows to study prompt line emission at 4.4 and 6.1 MeV; photons from 0.3 to 0.35 MeV were recorded with a 64-ms resolution. The high-energy detector consisted of the seven NaI front detectors of the gamma-ray spectrometer and the large 25-cm diameter by 7.6-cm CsI back detector. Events in the 10- to 100-MeV range occurring in this total detector mass were analyzed by separate pulse-height analyzers. Neutrons above 20 MeV could be distinguished by a difference in signature and in time of flight from the solar surface. The high-energy system had a 2-s time resolution. The auxiliary X-ray detector consisted of two 0.6-cm thick NaI detectors, one with an Al filter to cover the 10- to 80-keV range and the other with an Al-Fe filter to cover the 25- to 140-keV range. The X-ray system had a time resolution of 1 s and four energy channels. For more details on this experiment see D. J. Forrest et al., Solar Physics, v. 65, p. 15, 1980.
Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Allan S. Jacobson | Other Investigator | NASA Jet Propulsion Laboratory | |
Dr. James D. Kurfess | Other Investigator | US Naval Research Laboratory | kurfess@osse.nrl.navy.mil |
Dr. Klaus Pinkau | Other Investigator | Max-Planck-Institut fur Extraterrestrische Physik | |
Dr. Robert L. Kinzer | Other Investigator | US Naval Research Laboratory | kinzer@osse.nrl.navy.mil |
Dr. David J. Forrest | Other Investigator | University of New Hampshire | dave.forrest@unh.edu |
Dr. W. Neil Johnson | Other Investigator | US Naval Research Laboratory | johnson@osse.nrl.navy.mil |
Dr. Gerald H. Share | Other Investigator | US Naval Research Laboratory | share@osse.nrl.navy.mil |
Dr. Claus Reppin | Other Investigator | Max-Planck-Institut fur Extraterrestrische Physik | |
Dr. E. Rieger | Other Investigator | Max-Planck-Institut fur Extraterrestrische Physik | |
Dr. Edward L. Chupp | Principal Investigator | University of New Hampshire | elc@christa.unh.edu |