MERLIN and VLBA observations of Cygnus X-3

Abstract

We present new results from a radio mapping campaign on the X-ray binary (XRB), Cygnus X-3 using both MERLIN and the VLBA. This has produced two significant results. Firstly, observations using MERLIN at 5 GHz during a quiescent phase in June 1995 showed the presence of N and S radio lobes associated with a bright core. The position angle and separation of these lobes are consistent with the idea of a large scale jet in this source. Secondly, observations with the VLBA at 15 GHz during a period of small scale flaring have shown the source to be expanding at apparently superluminal velocities. This expansion was then followed by a period of apparent contraction with similar superluminal speeds.