ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288

Details ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288 ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288

1999-02-23

arxiv.org/abs/astro-ph/9902330v2

Astronomy and Astrophysics

Astrophysics

The Astrophysical Journal in press. Minor revisions to improve presentation. 6 pages with 3 embedded Postscript figures in emu

Scientific paper

10.1086/307806

A ROSAT HRI X-ray image was obtained of the open globular cluster NGC 288, which is located near the South Galactic Pole. This is the first deep X-ray image of this system. We detect a Low Luminosity Globular Cluster X-ray source (LLGCX) RXJ005245.0-263449 with an X-ray luminosity of (5.5+-1.4)x10^32 ergs/s (0.1-2.0 keV), which is located very close to the cluster center. There is evidence for X-ray variability on a time scale of <~ 1 day. The presence of this LLGCX in such an open cluster suggests that dense stellar systems with high interaction rates are not needed to form LLGCXs. We also searched for diffuse X-ray emission from NGC 288. Upper limits on the X-ray luminosities are L_X^h < 9.5x10^32 ergs/s (0.52-2.02 keV) and L_X^s < 9.3x10^32 ergs/s (0.11-0.41 keV). These imply upper limits to the diffuse X-ray to optical light ratios in NGC 288 which are lower than the values observed for X-ray faint early-type galaxies. This indicates that the soft X-ray emission in these galaxies is due either to a component which is not present in globular clusters (e.g., interstellar gas, or a stellar component which is not found in low metallicity Population II systems), or to a relatively small number of bright Low Mass X-ray Binaries (LMXBs).

Affiliated with

Also associated with

No associations

Rating

ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ROSAT HRI X-ray Observations of the Open Globular Cluster NGC 288 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-319403