Research Note

A study of the metal-rich, thick disk globular cluster NGC 5927^⋆,⋆⋆

A stellar inventory

¹ Lund Observatory, Box 43, 221 00 Lund, Sweden
e-mail: sofia@astro.lu.se
² University of Utah, Department of Physics and Astronomy, Salt Lake City, UT 84112, USA
e-mail: jennifer@physics.utah.edu
³ European Southern Observatory, Karl-Schwarzschild Str. 2, 85748 Garching b. München, Germany
e-mail: fprimas@eso.org

Received: 12 November 2012
Accepted: 22 April 2013

Abstract

We present a list of 72 radial velocity member stars in the metal-rich globular cluster NGC 5927. The radial velocities are based on multiepoch, multifibre spectra. We identify 46 RGB/HB stars and 26 turn-off stars that are radial velocity members in the cluster. This cluster is situated quite close to the disk and hence fore- and/or background contamination, especially in the outskirts of the cluster, can be quite severe. Fortunately, the cluster has a radial velocity (we determine it to v_r = −104.03 ± 5.03 km s^-1) that sets it clearly apart from the bulk velocities of the surrounding, background, and foreground stellar populations. Hence, our identification of members is clean and we can quantify a 50% contamination when stars in the outer part of the cluster are selected solely based on position in the color−magnitude diagram as opposed to selections based on radial velocities.