Bibcode
Martínez-Vázquez, C. E.; Stetson, P. B.; Monelli, M.; Bernard, E. J.; Fiorentino, G.; Gallart, C.; Bono, G.; Cassisi, S.; Dall'Ora, M.; Ferraro, I.; Iannicola, G.; Walker, A. R.
Referencia bibliográfica
Monthly Notices of the Royal Astronomical Society, Volume 462, Issue 4, p.4349-4370
Fecha de publicación:
11
2016
Número de citas
52
Número de citas referidas
46
Descripción
We present the identification of 634 variable stars in the Milky Way
dwarf spheroidal (dSph) satellite Sculptor based on archival
ground-based optical observations spanning ˜24 yr and covering
˜2.5 deg2. We employed the same methodologies as the
`Homogeneous Photometry' series published by Stetson. In particular, we
have identified and characterized one of the largest (536) RR Lyrae
samples so far in a Milky Way dSph satellite. We have also detected four
Anomalous Cepheids, 23 SX Phoenicis stars, five eclipsing binaries,
three field variable stars, three peculiar variable stars located above
the horizontal branch - near to the locus of BL Herculis - that we are
unable to classify properly. Additionally, we identify 37 long period
variables plus 23 probable variable stars, for which the current data do
not allow us to determine the period. We report positions and finding
charts for all the variable stars, and basic properties (period,
amplitude, mean magnitude) and light curves for 574 of them. We discuss
the properties of the RR Lyrae stars in the Bailey diagram, which
supports the coexistence of subpopulations with different chemical
compositions. We estimate the mean mass of Anomalous Cepheids
(˜1.5 M⊙) and SX Phoenicis stars (˜1
M⊙). We discuss in detail the nature of the former. The
connections between the properties of the different families of variable
stars are discussed in the context of the star formation history of the
Sculptor dSph galaxy.