I. Soszynski, A. Udalski, P. Pietrukowicz, M. K. Szymanski, M. Kubiak, G. Pietrzynski, L. Wyrzykowski, K. Ulaczyk, R. Poleski, S. Kozlowski
The fourteenth part of the OGLE-III Catalog of Variable Stars (OIII-CVS)
contains Cepheid variables detected in the OGLE-II and OGLE-III fields toward
the Galactic bulge. The catalog is divided into two main categories: 32
classical Cepheids (21 single-mode fundamental-mode F, four first-overtone 1O,
two double-mode F/1O, three double-mode 1O/2O and two triple-mode 1O/2O/3O
pulsators) and 335 type II Cepheids (156 BL Her, 128 W Vir and 51 RV Tau
stars). Six of the type II Cepheids likely belong to the Sagittarius Dwarf
Spheroidal Galaxy. The catalog data include the time-series photometry
collected in the course of the OGLE survey, observational parameters of the
stars, finding charts, and cross-identifications with the General Catalogue of
Variable Stars.
We discuss some statistical properties of the sample and compare it with the
OGLE catalogs of Cepheids in the Large and Small Magellanic Clouds. Multi-mode
classical Cepheids in the Galactic bulge show systematically smaller period
ratios than their counterparts in the Magellanic Clouds. BL Her in the Galactic
bulge stars seem to be brighter than the linear extension of the
period-luminosity relation defined by the longer-period type II Cepheids. We
also show individual stars of particular interest, like two BL Her stars with
period doubling.
View original:
http://arxiv.org/abs/1112.1406
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