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15-Minute Interplanetary Cruise Data in SFDU Format


Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)

Time span: 1973-04-06 to 1996-06-30


This data set is packaged in SFDU format and contains cruise data at 15 minute time resolution from launch for cosmic ray proton and electron measurements, primarily in interplanetary space, from the Geiger Tube Telescope (GTT) experiment. Integral counting rates are included for single and multiple coincidence events registering in one or more of six Geiger tubes (A-F) or for single events in the seventh (G) tube. Threshold energies for events in various data channels are 0.06-31 MeV for electrons and 6.6-150 MeV for protons. Each data record includes the UT time at the spacecraft for the start of the 15 minute interval, counting rates in counts/sec, Fourier coefficients for anisotropy measurements, and trajectory information. Items such as effective counts and raw counts are also provided to verify and allow future changes in data processing software. Each fixed length data record of length 932 bytes consists of 120 VAX binary words in 32 bit integer and 64 bit floating point formats. Each data tape contains two SFDU metadata files describing the Pioneer mission, GTT experiment, and the data set, one file consisting of a FORTRAN program for listing of the 15 minute data, one file of GTT-related publication listings, and a series of GTT data files, each corresponding to the first or second six months of data in consecutive years. An account of cruise data analysis through 1984 is given in Van Allen and Randall, J. Geophys. Res., 90, 1399-1412, 1985.

Alternate Names

  • 15 min GTT Interplanet Data,SFDU


  • Space Physics: Heliospheric Studies


  • 73-019A-11E

Additional Information



Questions and comments about this data collection can be directed to: Dr. John F. Cooper



NameRoleOriginal AffiliationE-mail
Dr. Bruce A. RandallData ProviderUniversity of
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