Cygnus X-3 - A cocooned X-ray binary pulsar

Abstract

It is shown that observations of both the hard X-ray and gamma-ray spectrum and the gamma-ray light curves of Cyg X-3 find a natural explanation in a model for the system of a fast binary pulsar (with a period between 10 and 30 ms) surrounded by a cocoon (of scattering optical depth unity) located about 1 trillion cm from the pulsar. The possibility of direct observation of pulsations is discussed, and attention is called to an anomalous behavior of gamma-rays in the vicinity of 0.5 MeV predicted by the model.