Clusters AgeS Experiment. Hot subdwarfs and luminous white dwarf candidates in the field of the globular cluster M4

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

16 pages LaTeX, 14 PostScript figures, 5 tables, major revisions, accepted to AJ

Scientific paper

10.1086/342015

We present UBV color magnitude diagrams (CMDs) for the globular cluster M4. The CMDs show a sequence of four luminous blue stars (V<20, U-V<-0.6) which appear to be cluster hot subdwarfs. We present spectra for the three brightest ones. We also note the presence of a population of faint blue objects, likely to be hot, young white dwarfs (WDs) belonging to the cluster. We have selected five objects above V=22 mag, bright enough for follow-up ground-based spectroscopy and present their coordinates and finding charts. We show a spectrum for variable V46 (Kaluzny et al. 1997) which suggests that it is a hot subdwarf, along with a new light curve obtained with the ISIS image subtraction package (Alard 2000). The light curve is unstable, but only one period of variability is apparent. Two new variables have been discovered, both located on the cluster red giant branch (RGB). We also present a differential E(B-V) reddening map and a fiducial sequence for the main sequence, subgiant branch and red giant branch on the V/B-V CMD for a selected region with uniform reddening. Based on a comparison with the M5 fiducial sequence we obtain a reddening estimate of E(B-V)=0.41 mag towards M4, consistent with previous determinations.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Clusters AgeS Experiment. Hot subdwarfs and luminous white dwarf candidates in the field of the globular cluster M4 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 Clusters AgeS Experiment. Hot subdwarfs and luminous white dwarf candidates in the field of the globular cluster M4, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clusters AgeS Experiment. Hot subdwarfs and luminous white dwarf candidates in the field of the globular cluster M4 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-268578

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.