Variable stars in the bulge globular cluster NGC 6401
Abstract
We present a study of variable stars in globular cluster NGC 6401. The cluster is only 5.3º away from the Galactic centre and suffers from strong differential reddening. The photometric precision afforded us by difference image analysis resulted in improved sensitivity to variability in formerly inaccessible interior regions of the cluster. We find 23 RRab and 11 RRc stars within one cluster radius (2.4'), for which we provide coordinates, finder-charts and time-series photometry. Through Fourier decomposition of the RR Lyrae star light curves we derive a mean metallicity of [Fe/H]UVES = -1.13 ± 0.06 ([Fe/H]ZW = -1.25 ± 0.06), and a distance of d ≈ 6.35 ± 0.81 kpc. Using the RR Lyrae population, we also determine that NGC 6401 is an Oosterhoff type I cluster.
Citation
Tsapras , Y , Arellano Ferro , A , Bramich , D M , Jaimes , R F , Kains , N , Street , R , Hundertmark , M , Horne , K , Dominik , M & Snodgrass , C 2017 , ' Variable stars in the bulge globular cluster NGC 6401 ' , Monthly Notices of the Royal Astronomical Society , vol. 465 , no. 2 , pp. 2489-2504 . https://doi.org/10.1093/mnras/stw2773
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
ISSN
0035-8711Type
Journal article
Rights
© 2016, the Author(s). This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at www.academic.oup.com / https://doi.org/10.1093/mnras/stw2773
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