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 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 approximate to 1600 WDs in the ( F658N - F625W, F625W)- plane, supporting the evidence that a large fraction of current cluster WDs are H alpha-bright.
Monelli, M., Corsi, C.e., Castellani, V., Ferraro, I., Iannicola, G., Prada Moroni, P.g., et al. (2005). The discovery of more than 2000 white dwarfs in the globular cluster omega Centauri. THE ASTROPHYSICAL JOURNAL LETTERS, 621, 117-120 [10.1086/429255].
The discovery of more than 2000 white dwarfs in the globular cluster omega Centauri
BONO, GIUSEPPE;BUONANNO, ROBERTO;
2005-01-01
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 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 approximate to 1600 WDs in the ( F658N - F625W, F625W)- plane, supporting the evidence that a large fraction of current cluster WDs are H alpha-bright.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
