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A-2 First Cut (FCUT) Background Database


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

Time span: 1977-08-12 to 1979-01-09


The HEAO-1 A-2 First Cut (FCUT) Background Analysis database is a secondary data base derived from the analysis of scanning data in the primary MAX data base (77-075A-02N), when there were no sources in the detector field of view. Analyses are performed to calculate the diffuse X-ray background, the non-X-ray background, the X-ray anisotropy, and the detector calibration using super-super clean Pulse Height Analysed (PHA) and/or Discovery Scaler (DS) (standard coincidence counting rates) data of the Medium Energy Detector (MED) and the three High Energy Detectors (HED). Each file on the tape consists of the beginning and end times of the background analysis interval, detector modes, and diffuse background PHA and DS accumulations.

Alternate Names

  • A-2 FCUT Background Database


  • Astronomy: X-Ray


  • 77-075A-02Q

Additional Information



Questions and comments about this data collection can be directed to: Dr. Cynthia Y. Cheung



NameRoleOriginal AffiliationE-mail
Dr. Laura A. WhitlockData ProviderNASA Goddard Space Flight
Dr. Jean H. SwankGeneral ContactNASA Goddard Space Flight
Mr. Brendan H. PerryProgrammerNASA Goddard Space Flight

Selected References

  • Piccinotti, G., et al., A complete X-ray sample of the high latitude (1b1 greater than 20 degree) sky from HEAO -1 A-2: Log N - log S and luminosity functions, NASA-GSFC, TM-82168, Greenbelt, MD, Aug. 1981.
  • Boldt, E., et al., Cosmic X-ray background: 1. The discrete source component, in (COSPAR) X-Ray Astronomy, 443-448, W.A. Baity, Pergamon Press, New York, NY, 1979.
  • Nugent, J. J., et al., HEAO A-2 soft X-ray source catalog, Astrophys. J. Suppl. Ser., 51, 1-28, doi:10.1086/190838, Jan. 1983.
  • Rothschild, R. E., et al., The cosmic X-ray experiment aboard HEAO-1, Space Sci. Instrum., 4, 269-301, 1979.
  • Marshall, F. E., et al., New hard X-ray sources observed with HEAO A-2, Astrophys. J. Suppl. Ser., 40, No. 3, 657-666, doi:10.1086/190600, July 1979.
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