CCD photometry of variable stars in the field of the globular cluster NGC 6397*
Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warsaw, Poland
Send offprint request to: J. Kaluzny
Accepted: 18 June 1996
The field including the central part of the globular cluster NGC 6397 was surveyed in a search for short-period variable stars. We obtained light curves for 6 close binaries, 2 SX Phe stars and 1 RR Lyrae variable, 7 of which are new discoveries. Both identified SX Phe variables are likely members of the cluster. One of the identified eclipsing binaries is most probably a field star while for the remaining 5 binaries our data do not preclude cluster membership. A . color-magnitude diagram extending from the tip of the red giant branch to below the main-sequence turnoff is presented.
Key words: globular clusters: individual: NGC 6397 / star: variables: other / HR diagram / blue stragglers / stars: close binaries
The data presented in Figs. 1, 2, 4 and 5 are available in electronic form at the CDS, via ftp 22.214.171.124
© European Southern Observatory (ESO), 1997