The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. Type II Cepheids in the Galactic Bulge - Supplement

TL;DR

This paper expands the OGLE-III catalog of Type II Cepheids in the Galactic bulge by adding 22 RV Tau stars, including some with long-period modulation, and compares their distribution to Magellanic Cloud samples.

Contribution

It provides an updated catalog of 357 Type II Cepheids, including newly identified RV Tau stars with some exhibiting RVb-type variability.

Findings

Number of RV Tau stars in the bulge is comparable to Magellanic Cloud samples.

Four new RV Tau stars show long-period luminosity modulation.

The relative proportion of RV Tau stars is similar across different environments.

Abstract

We report the discovery of additional 22 RV Tau stars located in the OGLE-II and OGLE-III fields toward the Galactic bulge, increasing to 357 objects the OGLE-III catalog of type II Cepheids in the Galactic center. Four of the newly detected RV Tau stars belong to the RVb class, i.e. they show large-amplitude, long-period modulation of the mean luminosity. In the updated catalog, the relative number of RV Tau stars in the whole sample of the Galactic bulge type II Cepheids is similar to the Magellanic Cloud samples.