Please use this identifier to cite or link to this item:
Title: New variables in M5 (NGC 5904) and some identification corrections
Authors: Arellano Ferro, A
Bramich, D. M
Giridhar, S
Luna, A
Muneer, S
Issue Date: 15-Apr-2015
Publisher: Konkoly Observatory
Citation: Information Bulletin on Variable Stars, No. 6137
Abstract: The bright globular cluster M5 (NGC 5904) has been the subject of many variable star searches for more than a hundred years. The first variables were discovered by Solon I. Bailey with the 13-inch Boyden Telescope at the Arequipa station in 1896 (see Pickering 1896 and Bailey 1899). The catalogue of variable stars in globular clusters (CVSGC; Clement et al. 2001) lists 169 variables, mostly of the RR Lyrae type, with 5 SX Phe stars, one W Virginis star (CW), one RV Tau, one (possibly two) eclipsing binaries, and one U Gem type star. However, there are also a number of uncertain classifications and some variables have an unknown type, or it is not even clear if they are truly variable. A new study of the variable stars in M5 is therefore pertinent. As part of our program of CCD time-series observations of variable star populations in globular clusters (GC), we performed CCD V and I photometry of the globular cluster M5. Difference image analysis (DIA) has proven to be very efficient in identifying variable stars even in the crowded central regions of GCs (e.g. Arellano Ferro et al. 2013 and references therein). Exploration of our collection of light curves of all stars in the field of our images down to V ~ 18.5 mag allowed us to identify twelve variables not previously detected; one SX Phe and eleven semi-regular variables (SR). In the present note, we report on their identifications, equatorial coordinates, ephemerides, and light curves. We argue that the known variable V155, previously classified as RRc, is in fact a contact eclipsing binary or EW. Furthermore, we have explored the light curves of a group of stars whose variability has not been confirmed and that are marked as probable non-variables in the CVSGC. Finally, we offer detailed identifications for some of the known variables in crowded regions that were misidentified in previous studies. We shall also address the cases of the cataclysmic variable or U Gem type V101 and of the variable blue straggler V159.
Description: Open Access
ISSN: 0374-0676
???metadata.dc.rights???: © Konkoly Observatory
Appears in Collections:IIAP Publications

Files in This Item:
File Description SizeFormat 
New variables in M5 (NGC 5904) and some identification corrections.pdfOpen Access2.48 MBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.