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Cosmic X-Ray Experiment (A-2) MAX Database


Availability: At NSSDC, Ready for Electronic Access

Time span: 1977-08-14 to 1979-01-10


The HEAO-1 A-2 MAX database is the primary data base of the A-2 experiment and contains all the telemetered data. The telemetry stream has been time-ordered and a series of quality flags have been set based on the data quality, engineering/science format, earth occultation, electron contamination, magnetic field direction, and the South Atlantic/North Pacific Anomalies. Each file of the MAX data base normally contains 12 hours of data, corresponding to a single spin axis position. A data analysis package is available on the microVAX of the GSFC Laboratory for High Energy Astrophysics. Several subset databases have been extracted from the MAX data base to increase the speed of data analysis. They are (1) the PHA database (77-075A-02H); (2) the XRATES database (77-075A-02I); (3) the North Ecliptic Pole database (77-075A-02J); (4) the South Ecliptic Pole database (77-075A-02K); (5) the Galactic Plane database (77-075A-02L); and (6) the Map database (77-075A-02M).

In December, 2000, the PI team delivered to NSSDC these data on a set of 25 CD-R disks allowing NSSDC to release the older magnetic tapes. Note that a version of this database is network-accessible from HEASARC.

Alternate Names

  • A-2 MAX Database


  • Astronomy: X-Ray


  • 77-075A-02N

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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