Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 2008 | Published
Journal Article Open

The variable stars of the Draco dwarf spheroidal galaxy: revisited

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 (RRL) stars, 9 anomalous Cepheids (ACs), 2 eclipsing binaries, and 12 slow, irregular red variables, as well as 30 background QSOs. Twenty-six probable double-mode RRL stars were identified. Observed parameters, including mean V and I magnitudes, V amplitudes, and periods, have been derived. Photometric metallicities of the ab-type RRL 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 RRL stars in Draco is reconfirmed, although the double-mode RRL stars, with one exception, have properties similar to those found in Oosterhoff type II globular clusters. The period-luminosity relation of the ACs is rediscussed with the addition of the new Draco ACs.

Additional Information

© 2008 The American Astronomical Society. Received 2007 October 12, accepted for publication 2008. August 12. Published 2008 October 9. This research used the facilities of the Canadian Astronomy Data Centre operated by the National Research Council of Canada with the support of the Canadian Space Agency. The identification of QSOs is based partly on spectra obtained with the Hydra multifiber spectrograph on the WIYN telescope at Kitt Peak National Observatory, National Optical Astronomical Observatories. NOAO is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation. This research has made use of the USNOFS Image and Catalogue Archive operated by the United States Naval Observatory, Flagstaff Station (http://www.nofs.navy.mil/data/fchpix/). H.A.S. acknowledges support from NSF grant AST 0607249. K.K. acknowledges support from NSF grant AST-0307778. The authors thank the referee, Gisella Clementini, for very useful comments and detailed suggestions for the overall improvement of this paper.

Attached Files

Published - KINaj08.pdf

Files

KINaj08.pdf
Files (1.6 MB)
Name Size Download all
md5:b532667c681f6b636c3ad68987c6deb5
1.6 MB Preview Download

Additional details

Created:
August 22, 2023
Modified:
October 17, 2023