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Discovery of more than two thousand white dwarfs in the globular cluster Omega Centauri

M. Monelli·C. E. Corsi·V. Castellani·I. Ferraro·G. Iannicola·P. G. Prada Moroni·G. Bono·R. Buonanno·A. Calamida·L. M. Freyhammer·L. Pulone·P. B. Stetson
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Abstract

We present deep multiband (F435W, F625W, and F658N) photometric data of the Globular Cluster Omega Cen collected with the Advanced Camera for Surveys on board of the Hubble Space Telescope. We identified in the (F435W-F625W, F435W) plane more than two thousand White Dwarf (WD) candidates using three out of nine available pointings. Such a large sample appears in agreement with predictions based on the ratio between WD and Horizontal Branch (HB) 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 $H_α$ bright.

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M. Monelli, C. E. Corsi, V. Castellani, I. Ferraro, G. Iannicola, P. G. Prada Moroni, G. Bono, R. Buonanno, A. Calamida, L. M. Freyhammer, L. Pulone, P. B. Stetson. 2005-01-28. Discovery of more than two thousand white dwarfs in the globular cluster Omega Centauri. https://doi.org/10.1086/429255

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