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astro-ph2003

The Chemical Composition Contrast between M3 and M13 Revisited: New Abundances for 28 Giant Stars in M3

Christopher Sneden, Robert P. Kraft, Puragra Guhathakurta +2

We report new chemical abundances of 23 bright red giants of the globular cluster M3, based on high-resolution spectra obtained with the Keck I telescope. Combining these data with…

astro-ph2003

A Survey for EHB Stars in the Galactic Bulge

Donald M. Terndrup, Deokkeun An, Angela Hansen +3

We present a progress report on an extensive survey to find and characterize all types of blue horizontal-branch stars in the nuclear bulge of the Galaxy. We have obtained wide, sh…

astro-ph2003

Blue Horizontal Branch Stars in Old, Metal-Rich Stellar Systems

Ruth C. Peterson, Bruce W. Carney, Ben Dorman +5

Twenty years ago, Burstein et al. (1984)suggested that strong CN and Hbeta absorption meant younger ages among globular clusters in the Andromeda galaxy (M31), unless blue stars ab…

astro-ph2002

Hubble Space Telescope Evidence for an Intermediate-Mass Black Hole in the Globular Cluster M15: II. Kinematical Analysis and Dynamical Modeling

Joris Gerssen, Roeland P. van der Marel, Karl Gebhardt +3

We analyze HST/STIS spectra (see Paper I) of the central region of the dense globular cluster M15. We infer the velocities of 64 individual stars, two-thirds of which have their ve…

astro-ph2002

Addendum: "Hubble Space Telescope Evidence for an Intermediate-Mass Black Hole in the Globular Cluster M15: II. Kinematical Analysis and Dynamical Modeling"

Joris Gerssen, Roeland P. van der Marel, Karl Gebhardt +3

It has been reported that there is an error in the figure in Dull et al. (1997, D97) that shows the radial M/L profile in Fokker-Planck models of M15. We discuss how this modifies…

astro-ph2000

Chromospheric Activity in Metal-Poor Dwarfs

Ruth C. Peterson, Carolus J. Schrijver

We have obtained echelle spectra with the Hubble Space Telescope (HST) of the MgII 2800A region of ten stars whose metallicities range from 1/300 to 1/3 that of the Sun, and whose…