Soft X-ray emission from intermediate-age open clusters: IC 4651
Abstract
We present the results of soft X-ray observations of the intermediate-age open cluster IC 4651 performed with the ROSAT PSPC. We detected 25 sources. Two are identified with a giant binary and a blue straggler respectively, both belonging to the cluster, and two with probable main-sequence members. Two other cases have ambiguous identification. Of the five binaries known in the cluster, the one detected in X rays is the only one whose period is short enough to maintain fast rotation and therefore strong stellar activity at a high age. The detected blue straggler is probably binary, suggesting that binarity is the key to producing a high level of X-ray emission. It is the third blue straggler detected in X rays. The remaining sources need to be identified through optical follow-up.
Cite
@article{arxiv.astro-ph/9804056,
title = {Soft X-ray emission from intermediate-age open clusters: IC 4651},
author = {T. Belloni and G. Tagliaferri},
journal= {arXiv preprint arXiv:astro-ph/9804056},
year = {2007}
}
Comments
Accepted for publications in Astronomy and Astrophysics; 6 pages, including 1 figure