Stellar Populations in the Phoenix Dwarf (dIrr/dSph) Galaxy as Observed by HST/WFPC2
Astrophysics
2009-10-31 v1
Abstract
We present HST/WFPC2 photometry of the central regions of the Phoenix dwarf. Accurate photometry allows us to: 1) confirm the existence of the horizontal branch previously detected by ground-based observations, and use it to determine a distance to Phoenix, 2) clearly detect the existence of multiple ages in the stellar population of Phoenix, 3) determine a mean metallicity of the old red giant branch stars in Phoenix, and suggest that Phoenix has evolved chemically over its lifetime, 4) extract a rough star formation history for the central regions which suggests that Phoenix has been forming stars roughly continuously over its entire lifetime.
Keywords
Cite
@article{arxiv.astro-ph/0008468,
title = {Stellar Populations in the Phoenix Dwarf (dIrr/dSph) Galaxy as Observed by HST/WFPC2},
author = {Jon A. Holtzman and Graeme H. Smith and Carl Grillmair},
journal= {arXiv preprint arXiv:astro-ph/0008468},
year = {2009}
}
Comments
Accepted by AJ, 22 pages including 6 figures + 1 figure in JPEG format