Population II Cepheids

Abstract

AbstractA review of Cepheids in globular clusters finds 46 stars that are highly probable members of 21 clusters, all of intermediate to low metallicity with blue horizontal branches. In order to separate Type II Cepheids in the field from classical Cepheids, an analysis is made of the distribution of all Cepheids: 144 are sufficiently far from the galactic plane to be considered Type II. Their properties are compared with the cluster Cepheids. Some recent studies are reviewed that are improving our understanding of low-mass Cepheids.