ROSAT observations of globular clusters

Abstract

We present deep pointed observations of ten globular clusters obtained with the ROSAT PSPC, and one with the ROSAT HRI. X‐ray sources are detected in the cores of seven of them, at luminosities of ∼1–6×1032 erg s−1. At least two of these are multiple. Four have colors indicating soft spectra, with blackbody temperatures kT≲0.3 keV. Soft spectra can be excluded for the other three sources. The sources outside the cores are probably not associated with the cluster. The most likely counterparts for these sources are soft x‐ray transients (SXTs).