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Session 54 - Star Clusters, Kinematics and the Galactic Center.
Display session, Wednesday, June 10
Atlas Ballroom,

[54.01] A Complete Sample of Hot UV-Bright Stars in Globular Clusters

W. Landsman (Raytheon STX), S. Moehler, R. Napiwotzki (U.Erlangen-Nurnberg), T. Stecher (NASA/GSFC)

We present preliminary results of our program to obtain optical and ultraviolet spectra of all UV-bright objects discovered on wide-field (40') ultraviolet images of fourteen globular clusters observed with the Ultraviolet Imaging Telescope (UIT). The star M4-Y453 (Teff = 59,000 K, log g = 5.2) is the hottest post-AGB star without a planetary nebula yet found in a globular cluster. A STIS low-resolution ultraviolet spectrum of NGC 6723 - III60 (Teff = 40,000 K, log g = 5.2) shows a large overabundance of nitrogen. The sdO stars in globular clusters can be classified as either post-EHB (extreme horizontal branch) stars with strong helium depletions, or as post-AGB stars with approximately solar helium abundances.

Program listing for Wednesday