1 research outputs found
THE SWIFT UVOT STARS SURVEY. I. METHODS AND TEST CLUSTERS
We describe the motivations and background of a large survey of nearby stel-
lar populations using the Ultraviolet Optical Telescope (UVOT) aboard the Swift
Gamma-Ray Burst Mission. UVOT, with its wide field, NUV sensitivity, and 2.3
spatial resolution, is uniquely suited to studying nearby stellar populations
and providing insight into the NUV properties of hot stars and the contribution
of those stars to the integrated light of more distant stellar populations. We
review the state of UV stellar photometry, outline the survey, and address
problems spe- cific to wide- and crowded-field UVOT photometry. We present
color-magnitude diagrams of the nearby open clusters M 67, NGC 188, and NGC
2539, and the globular cluster M 79. We demonstrate that UVOT can easily
discern the young- and intermediate-age main sequences, blue stragglers, and
hot white dwarfs, pro- ducing results consistent with previous studies. We also
find that it characterizes the blue horizontal branch of M 79 and easily
identifies a known post-asymptotic giant branch star.Comment: 35 pages, 8 figures, accepted for publication in Astronomical Journa