The Ejection of Runaway Massive Binaries

The runaway O-type stars HD 14633 and HD 15137 are both SB1 systems that were probably ejected from the open cluster NGC 654 (Boyajian et al. 2005). Were these stars dynamically ejected by close gravitational encounters in the dense cluster, or did the binaries each receive a kick from a supernova in one member? We present new results from our investigation of the optical, UV, X-ray, and radio properties of these binary systems to discuss the probable ejection scenarios.