The Discovery of More than 2000 White Dwarfs in the Globular Cluster ω Centauri

Abstract

We present deep multiband (F435W, F625W, and F658N) photometric data of the globular cluster ω Cen collected with the Advanced Camera for Surveys on board the Hubble Space Telescope. We identified in the (F435W - F625W, F435W)-plane more than 2000 white dwarf (WD) candidates using three out of nine available pointings. Such a large sample appears to be in agreement with predictions based on the ratio between WD and horizontal-branch evolutionary lifetimes. We also detected ~1600 WDs in the (F658N - F625W, F625W)-plane, supporting the evidence that a large fraction of current cluster WDs are Hα-bright. Based on observations collected with the Advanced Camera for Surveys on board the Hubble Space Telescope.