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arXiv · 0808.2542

The Variable Stars of the Draco Dwarf Spheroidal Galaxy - Revisited

K. Kinemuchi·H. C. Harris·Horace A. Smith·N. A. Silbermann·L. A. Snyder·A. P. LaCluyze·C. L. Clark
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Abstract

We present a CCD survey of variable stars in the Draco dwarf spheroidal galaxy. This survey, which has the largest areal coverage since the original variable star survey by Baade & Swope, includes photometry for 270 RR Lyrae stars, 9 anomalous Cepheids, 2 eclipsing binaries, and 12 slow, irregular red variables, as well as 30 background QSOs. Twenty-six probable double-mode RR Lyrae stars were identified. Observed parameters, including mean V and I magnitudes, V amplitudes, and periods, have been derived. Photometric metallicities of the ab-type RR Lyrae stars were calculated according to the method of Jurcsik & Kovacs, yielding a mean metallicity of <[Fe/H]> = -2.19 +/- 0.03. The well known Oosterhoff intermediate nature of the RR Lyrae stars in Draco is reconfirmed, although the double-mode RR Lyrae stars with one exception have properties similar to those found in Oosterhoff type II globular clusters. The period-luminosity relation of the anomalous Cepheids is rediscussed with the addition of the new Draco anomalous Cepheids.

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K. Kinemuchi, H. C. Harris, Horace A. Smith, N. A. Silbermann, L. A. Snyder, A. P. LaCluyze, C. L. Clark. 2008-08-19. The Variable Stars of the Draco Dwarf Spheroidal Galaxy - Revisited. https://doi.org/10.1088/0004-6256%2F136%2F5%2F1921

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