Astronomy and Astrophysics – Astrophysics
Scientific paper
1996-09-20
Astrophys.J. 472 (1996) L97
Astronomy and Astrophysics
Astrophysics
13 pages including 1 table and 3 figures in AASTeX 4.0; To appear in The Astrophysical Journal Letters, volume 472 (1996 Decem
Scientific paper
10.1086/310373
The intense, bursting X-ray source in the globular cluster NGC 1851 was one of the first cluster sources discovered, but has remained optically unidentified for 25 years. We report here on results from Hubble Space Telescope WFPC2 multicolor images in NGC 1851. Our high spatial resolution images resolve ~200 objects in the 3'' radius Einstein X-ray error circle, 40 times as many as in previous ground-based work. A color-magnitude diagram of the cluster clearly reveals a markedly UV-excess object with B~21, (U-B) ~ -0.9 only 2'' from the X-ray position. The UV-excess candidate is 0.12'' distant from a second, unremarkable star that is 0.5 mag brighter in B; thus ground-based studies of this field are probably impractical. Three other UV-excess objects are also present among the ~16,000 objects in the surveyed region of the cluster, leaving a ~5% probability that a UV-excess object has fallen in the X-ray error circle by chance. No variability of the candidate is seen in these data, although a more complete study is required. If this object is in fact the counterpart of the X-ray source, previous inferences that some globular cluster X-ray sources are optically subluminous with respect to low-mass X-ray binaries in the field are now strengthened.
Anderson Scott F.
Deutsch Eric W.
Downes Ronald A.
Margon Bruce
No associations
LandOfFree
An Ultraviolet-Excess Optical Candidate for the Luminous Globular Cluster X-ray Source in NGC1851 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 An Ultraviolet-Excess Optical Candidate for the Luminous Globular Cluster X-ray Source in NGC1851, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Ultraviolet-Excess Optical Candidate for the Luminous Globular Cluster X-ray Source in NGC1851 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-198317