Recent Results on Extragalactic Cosmic X-Ray Sources from Rocket and Balloon Flights

Part of the International Astronomical Union / Union Astronomique Internationale book series (IAUH, volume 1)


Two experiments carried out recently at M.I.T. gave results which bear on the problems of extragalactic X-ray sources. One of these is the work of a group under the direction of Hale Bradt (Bradt et al., 1967), who used an attitude-controlled Aerobee rocket to scan a portion of the sky which included the radio galaxy M 87 (Virgo A). Among their detectors were two banks of argon-filled, 2 mil beryllium window proportional counters, each with an effective area of 350 cm2 and a mechanical collimator giving a 2°×20° FWHM field of view. The fields of view were crossed
Fig. 1.

Counting rates counters A and B during a scan of the region near M 87.

so that their long directions made an angle of 60° with one another. Aspect was determined to within 5 min of arc by star photography.


Coma Cluster Radio Galaxy Proportional Counter Crab Nebula Virgo Cluster 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Boldt, E., McDonald, F.B., Riegler, G., Serlemitsos, P. (1966) Phys. Rev. Letters, 17, 447.ADSCrossRefGoogle Scholar
  2. Bradt, H., Mayer, W., Naranan, S., Rappaport, S., Spada, G. (1967) Astrophys. J. (Letters), 150, 199.ADSCrossRefGoogle Scholar
  3. Byram, E.T., Chubb, T. A., Friedman, H. (1967) Science, 152, 66.ADSCrossRefGoogle Scholar
  4. Clark, G., Lewin, W., Smith, W. (1968) Astrophys. J., 151, 21.ADSCrossRefGoogle Scholar
  5. Felten, J.E., Gould, R.J., Stein, W.A., Woolf, N.J. (1967) Astrophys. J., 146, 955.ADSCrossRefGoogle Scholar
  6. Garmire, G. (1967) private communication.Google Scholar
  7. Lewin, W., Clark, G., Smith, W. (1967) Astrophys. J. (Letters), 150, 153.ADSCrossRefGoogle Scholar
  8. Peterson, L., Jacobsen, A. (1966) Astrophys. J., 145, 962.ADSCrossRefGoogle Scholar

Copyright information

© I.A.U. 1968

Authors and Affiliations

  1. 1.Massachusetts Institute of TechnologyCambridgeUSA

Personalised recommendations