CCD photometry of variable stars in the globular cluster NGC 288

Warsaw University Observatory, Al. Ujazdowskie  4, 00-478  Warsaw, Poland e-mail: jka@sirius.astrouw.edu.pl

Received: 3 January 1996
Accepted: 5 April 1996

Abstract

The central part of the globular cluster NGC 288 was surveyed in a search for short-period variable stars. We obtained V-band light curves for 4 SX Phe stars and 2 RR Lyrae variables, five of which are new discoveries. All SX Phe stars belong to blue stragglers. We present a color-magnitude diagram including stars from the tip of red giant branch to the level of the main-sequence turnoff. Three likely hot subdwarfs were located on the extension of the blue horizontal branch of the cluster.