X-ray observations of the variability of Cygnus X-1 in the high state.
Manzo, G.; Molteni, D.; Robba, N. R.; Bonnet-Bidaud, J. M.; Ilovaisky, S.
Italy, France
Abstract
The ESA COS-B satellite has observed the Cygnus region in the energy range 2-12 keV, between November 28 and December 24, 1975. The Cygnus X-1 X-ray light curve for this period, during which the source appears to be in the high state, is reported; a search for a possible attenuation of the X-ray emission at the superior conjunction brings to the conclusion that the evidence for the existence of such a feature is dubious.