IGR J17544-2619 in depth with suzaku: Direct evidence for clumpy winds in a supergiant fast X-ray transient

Abstract

We present direct evidence for dense clumps of matter in the companion wind in a Supergiant Fast X-ray Transient (SFXT) binary. This is seen as a brief period of enhanced absorption during one of the bright, fast flares that distinguish these systems. The object under study was IGR J17544-2619, and a total of 236 ks of data were accumulated with the Japanese satellite Suzaku. The activity in this period spans a dynamic range of almost 104 in luminosity and gives a detailed look at SFXT behavior. © 2009. The American Astronomical Society. All rights reserved.