Properties of X-ray Binaries in the Magellanic Clouds from RXTE and Chandra Observations

TL;DR

This study compares the properties of X-ray binaries in the Small Magellanic Cloud and the Milky Way, using long-term RXTE and Chandra observations to understand their differences and accretion processes.

Contribution

It provides a comprehensive analysis of SMC X-ray pulsars through decade-long RXTE monitoring and Chandra surveys, highlighting differences from Galactic counterparts.

Findings

SMC X-ray binary population is mostly transient Be/neutron star binaries.

Chandra provides precise locations and detects lower flux sources.

RXTE offers detailed timing studies of pulsating sources.

Abstract

The X-ray binary population of the SMC is very different from that of the Milky Way consisting, with one exception, entirely of transient pulsating Be/neutron star binaries. We have now been monitoring these SMC X-ray pulsars for over 10 years using the Rossi X-ray Timing Explorer with observations typically every week. The RXTE observations have been complemented with surveys made using the Chandra observatory. The RXTE observations are non-imaging but enable detailed studies of pulsing sources. In contrast, Chandra observations can provide precise source locations and detections of sources at lower flux levels, but do not provide the same timing information or the extended duration light curves that RXTE observations do. We summarize the results of these monitoring programs which provide insights into both the differences between the SMC and the Milky Way, and the details of the accretion processes in X-ray pulsars.