Low mass variable stars in the globular cluster NGC 6397

Abstract

We have conducted a photometric survey of the globular cluster NGC 6397 in a search for variable stars. We obtained ~11h of time-resolved photometric images with one ne European Southern Observatory-Very Large Telescope using the FOcal Reducer and low dispersion Spectrograph imager distributed over two consecutive nights. We analyzed 8391 light curves of stars brighter than magnitude 23 with the 465 nm-filter, and we identified 412 variable stars, reaching ~ 4.8 +- 0.2 per cent of variability with timescales between 0.004 and 2d, with amplitudes variation greater than +- 0.2 mag.

9 figures, complementary data

References in corpus (5)

• The White Dwarf Cooling Sequence of NGC6397
• BOSS Ultracool Dwarfs I: Colors and Magnetic Activity of M and L dwarfs
• Identification of Faint Chandra X-ray Sources in the Core-Collapsed Globular Cluster NGC 6397: Evidence for a Bimodal Cataclysmic Variable Population
• Probing Mass Segregation in NGC 6397
• M dwarfs in the b201 tile of the VVV survey: Colour-based Selection, Spectral Types and Light Curves