Interacting Stellar Winds in a Binary System

Abstract

It is now known that strong stellar winds develop in stars mostly at the red and blue sides of the HR diagram. However, although the mass loss rates observed in O and M stars are comparable, the corresponding wind velocities are vastly different. It would thus be of great interest to find a binary system, containing both a cool and a hot star each with its own wind, and observe the resultant interaction. For a long time, α Sco (Ml. 5 Iab + B2.5 V) was the only known example (Kudritzki and Reimers 1978, van der Hucht et al. 1980). The situation in this case is best illustrated by a VLA map made by Gibson (1979) who finds that a shock develops at the surface of interaction of the two winds. In this paper I shall describe another binary system in which two stellar winds are interacting with dramatic effects.