The bottom of the white dwarf cooling sequence in the old open cluster NGC 2158
Astrophysics of Galaxies
2015-05-14 v1 Solar and Stellar Astrophysics
Abstract
We use 10 orbits of Advanced Camera for Surveys observations to reach the end of the white dwarf cooling sequence in the solar-metallicity open cluster NGC 2158. Our photometry and completeness tests show that the end falls at magnitude m_F606W = 27.5 +/- 0.15, which implies an age between ~1.8 and ~2.0 Gyr, consistent with the age of 1.9 +/- 0.2 Gyr obtained from fits to the main-sequence turn-off. The faintest white dwarfs show a clear turn toward bluer colors, as predicted by theoretical isochrones.
Keywords
Cite
@article{arxiv.0912.0257,
title = {The bottom of the white dwarf cooling sequence in the old open cluster NGC 2158},
author = {L. R. Bedin and M. Salaris and I. R. King and G. Piotto and J. Anderson and S. Cassisi},
journal= {arXiv preprint arXiv:0912.0257},
year = {2015}
}
Comments
12 pages, 4 figures (2 in low resolution, and 1 bonus for astro-ph-only). ApJ Letter accepted on December 1, 2009