Variable Low-Mass X-ray Binaries in Early-Type Galaxies

Abstract

As the Chandra X-ray Observatory mission matures, increasing numbers of nearby galaxies are being observed multiple times, sampling the variability of extragalactic X-ray binaries on timescales extending from seconds to years. We present results on luminous low-mass X-ray binaries from several early-type galaxies. We show that instantaneous LMXB luminosity functions of early-type galaxies do not significantly change between observations; a relatively low fraction of sources are strongly variable on <~ 5 yr timescales. We discuss the implications that a relatively small number of transient LMXBs are being discovered in early-type galaxies.

Conference proceedings from 'A Population Explosion: The Nature and Evolution of X-ray Binaries in Diverse Environments', 28 Oct - 2 Nov, St. Petersburg Beach, FL. 5 pages, 2 B & W figures, 3 Color figures