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Galactic and Solar Cosmic Rays

NSSDCA ID: 1974-097A-08

Mission Name: Helios-A
Principal Investigator:Dr. James H. Trainor

Description

The detector complement of this experiment (E7) consisted of three separate dE/dx vs E telescopes and a proportional counter for monitoring solar X rays in the range 2-8 keV. The high-energy telescope had a geometric factor of 0.22 sq cm-sr and measured electrons in three ranges between 2 and 8 MeV, and protons and alpha particles in three ranges between 20 and 56 MeV/n. Protons above 230 MeV were also measured. The first low-energy telescope (geometric factor was 0.155 sq cm-sr) measured protons and Z>1 particles in three ranges between 3 and 21 MeV/n. The second low-energy telescope (geometric factor was 0.015 sq cm-sr) measured protons in several ranges between 0.12 and 2.1 MeV, alpha particles in the ranges 0.6-2.1 and 6-21.2 MeV/n, and electrons in four ranges between 0.12 and 2 MeV. For a number of coincidence modes, counting-rate data sectored into eight 45-deg sectors were obtained. The data cycle time was dependent on the spacecraft telemetry rate (variable between 4096 and 8 bits/s) and format. Under optimum conditions, five events per second were pulse-height analyzed and the rate data cycle was of the order of 5 min. At the slowest combination of bit rate and format, a complete data cycle required about 2.5 h. See IEEE Trans. on Nuc. Sci., NS-22, p. 570, 1975, and Raumfahrtforschung, v. 19, n. 5, pp. 258-260, 1975, for further details.

Alternate Names

  • Helios-A/GalacticandSolarCosmicRays

Disciplines

  • Astronomy: Cosmic Ray
  • Space Physics: Heliospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Dr. H. Kent Hills

 

Personnel

NameRoleOriginal AffiliationE-mail
Dr. Frank B. McDonaldOther InvestigatorUniversity of Maryland
Dr. Bonnard J. TeegardenOther InvestigatorNASA Goddard Space Flight Centerteegarden@tgrs.gsfc.nasa.gov
Dr. Kenneth G. McCrackenOther InvestigatorCommonwealth Scientific and Industrial Research Orqanisation
Dr. Edward C. RoelofOther InvestigatorApplied Physics Laboratoryedmond.roelof@jhuapl.edu
Dr. James H. TrainorPrincipal InvestigatorNASA Goddard Space Flight Center
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