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Energetic Particle Detectors

NSSDCA ID: 1973-009A-01

Mission Name: Prognoz 3
Principal Investigator:Dr. Yuri I. Logachev


This investigation utilized two semiconductor silicon detectors and two gas counters/plastic scintillators to measure energetic electron and proton fluxes perpendicular to the spin axis. The silicon detectors had sensitive layers 50 micrometers and 1.8 mm thick, and aluminum foil windows of 5 micrometers and 0.83 mm. The effective proton energy ranges were 1 to 5 and 14 to 30 MeV. Alpha particles and heavier nuclei which deposited sufficient energy in the crystals were also counted. Electron efficiency was very low (1E-4) and the cosmic-ray background rate for multiply charged nuclei was small (about 1E-2 counts/s). Therefore, minor increases in fluxes of solar origin could be observed. The fields of view were cones of approximately 60-deg full-angle, and the geometric factors were approximately 0.15 sq cm-sr. Protons of energy above 40 MeV and electrons above 2.5 MeV were detected by the plastic scintillators surrounding the gas counters. The flux of electrons with energies between 40 and 500 keV was determined from the difference of counting rates of two type SBT-9 gas counters, one of which had a magnetic filter in front of the window which deflected electrons of energy below 500 keV. Electrons of energy above 40 keV, and protons of energy above 0.8 MeV could penetrate the counter windows. The background counting rate was reduced by the use of the anti-coincidence scintillators surrounding the counters. The minimum electron flux detectable was 1 electron/(sq cm sr s).

Alternate Names

  • Prognoz3/EnergeticParticleDetectors


    Additional Information

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    NameRoleOriginal AffiliationE-mail
    Dr. Yuri I. LogachevPrincipal InvestigatorInstitute for Nuclear Physics
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