The Hot Stars of Old Open Clusters: I. M67 and NGC 188

Details The Hot Stars of Old Open Clusters: I. M67 and NGC 188 The Hot Stars of Old Open Clusters: I. M67 and NGC 188

Dec 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995aas...18710705l&link_type=abstract

American Astronomical Society, 187th AAS Meeting, #107.05; Bulletin of the American Astronomical Society, Vol. 27, p.1438

Astronomy and Astrophysics

Astronomy

Scientific paper

During the second flight of the Astro observatory in March 1995, we used the Ultraviolet Imaging Telescope (UIT) to obtain ultraviolet ( ~ 1600 Angstroms) images of five old open clusters. Most stars in an old open cluster are too cool to be detected in the ultraviolet, but among the possible UV-bright sources are blue stragglers, hot white dwarfs, and sdB or sdO stars. In NGC 188, we detect only the hot subdwarf and possible member II-91, and the blue straggler E43 (from Caputo et al. 1990, AJ, 99, 261). In M67, we detect ten blue stragglers, two white dwarf candidates (including the ROSAT source G152) and, surprisingly, the red giant S1040 from the catalogue of Sanders (1977). The star S1040 (V = 11.52, B--V = 0.82) is a single-lined spectroscopic binary with a period of 42.8 days, and an astrometric and radial-velocity member of M67 (Mathieu et al. 1990, AJ, 100, 1859). It occupies a ``red straggler'' position in the color-magnitude diagram (CMD), 0.2 mag blueward of the giant branch. Our detection of S1040 in the ultraviolet implies that (1) the secondary is likely a hot ( ~ 25,000 K) white dwarf, and (2) the unusual position of S1040 in the CMD is likely due to previous mass transfer from the white dwarf progenitor. We discuss the implications our observations for the study of mass transfer binaries, and the origin of the blue stragglers in M67.

Affiliated with

Also associated with

No associations

Rating

The Hot Stars of Old Open Clusters: I. M67 and NGC 188 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 The Hot Stars of Old Open Clusters: I. M67 and NGC 188, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Hot Stars of Old Open Clusters: I. M67 and NGC 188 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1256811