Observation of gamma rays with a 4.8 hour periodicity from Cygnus X-3
Publication date: 01 March 1977
Authors: Lamb, R.C., et al.
Journal: Astrophysical Journal Letters
Volume: 212
Page: 63-66
Year: 1977
Copyright: American Astronomical Society
Energetic (exceeding 35 MeV) gamma-rays have been observed from the direction of Cygnus X-3 with the SAS-2 gamma-ray telescope. The statistical significance of the excess above the galactic and diffuse radiation is approximately 4.5 sigma. In addition, the gamma-ray flux is modulated at the 4.8-hr period observed in the X-ray and infrared regions, and within the statistical error is in phase with this emission. The flux above 100 MeV has an average value of about