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Scintillation Counter

NSSDCA ID: 1959-004A-02

Mission Name: Explorer 6
Principal Investigator:Dr. Charles P. Sonett


The scintillation counter experiment was designed to make direct observations of electrons in the earth's radiation belts with a detector insensitive to bremsstrahlung. This experiment consisted of a cylindrical plastic scintillator cemented to a photomultiplier tube. The instrument viewed space through a foil-covered window in the payload shell, but the instrument also responded to more energetic particles passing through the payload shell. The minimum energies detectable were 200 keV for electrons and 2 MeV for protons. For electrons between 200 and 500 keV, the detector efficiency times the omnidirectional geometric factor was 0.0008 sq cm count per electron; whereas for electrons of energy greater than 500 keV, it was 0.16 sq cm count per electron. For very penetrating particles, the geometrical factor rose to its maximum value of 3.5 sq cm. The scintillation counter was sampled continuously for analog transmission and intermittently (every 2 min, 15 s, or 1.9 s, depending upon the satellite bit rate) for digital transmission. The transmitter broadcasting the analog data for this experiment failed on September 11, 1959. Data were received on a limited duty cycle from the digital transmitter until early October, 1959. NSSDC has all the useful data that now exist.

Alternate Names

  • Explorer6/ScintillationCounter
  • Scintillation Counter which Detected Electrons but not Bremsstrahlung

Facts in Brief

Mass: 2.1 kg

Funding Agencies

  • Department of Defense-Department of the Air Force (United States)
  • NASA-Office of Space Science Applications (United States)


  • Space Physics: Magnetospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Dr. Alan RosenOther InvestigatorTRW Systems Group
Dr. Thomas A. FarleyOther InvestigatorUniversity of California, Los Angeles
Dr. Charles P. SonettPrincipal InvestigatorUniversity of Arizona
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