Chandra X-Ray Observations of the Young Open Cluster NGC 2516
Abstract
We present a comprehensive study of the Chandra X-ray observations of the young open cluster NGC 2516. We have analyzed eight individual Chandra observations. We have combined the data to achieve the greatest sensitivity, reaching down to logfX=-14.56 (ergs s-1 cm -2), or logLX=28.69 (ergs s-1) at the distance of NGC 2516. Out of 284 X-ray sources detected, 155 are identified with photometric cluster members, with very little ambiguity. We have studied the X-ray luminosity functions for the various spectral types, correcting for nonmember contamination those for later type stars. We find strong X-ray emission from a couple of B stars that cannot be due to companions. Among A stars, chemically peculiar stars show a detection fraction much larger than normal A stars. The luminosity functions decrease monotonically from F to M stars, and those for K stars are significantly lower than similar stars in the Pleiades, a cluster only slightly younger than NGC 2516. We discuss possible causes of this discrepancy, including differences in age and stellar rotation.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 2003
- DOI:
- 10.1086/374214
- Bibcode:
- 2003ApJ...588.1009D
- Keywords:
-
- Galaxy: Open Clusters and Associations: Individual: NGC Number: NGC 2516;
- Stars: Coronae;
- X-Rays: Stars