Author(s): , , , ,
Institution(s): 1. Pennsylvania State University, 2. The George Washington University, 3. University of Toronto
The crisp vision of the Chandra X-ray Observatory resolved the extended emission from the gamma-ray binary PSR B1259-63/LS 2883. The series of observations spanning from 2009 to 2015 have shown that the extended X-ray feature is moving away from the binary with an average projected velocity of 0.07c and shows a hint of acceleration. The spectrum of the feature appears to be hard (photon index ~0.8) with no sign of softening compared to previously measured values. We interpret it as a clump of plasma ejected from the binary through the interaction of the pulsar with the decretion disk of the O-star around periastron passage. We suggest that the clump is moving in the unshocked relativistic pulsar wind, which can accelerate the clump. Its X-ray emission can be interpreted as synchrotron radiation of the pulsar wind shocked by the collision with the clump. Such objects have never been detected so far.