The Stellar Content and Distance of UGC 4483
Abstract
We present HST/WFPC2 observations of UGC 4483, an irregular galaxy in the M81/NGC 2403 complex. Stellar photometry was carried out with HSTphot, and is complete to V ~ 26.0 and I ~ 24.7. We measure the red giant branch tip at I = 23.56 +/- 0.10 and calculated a distance modulus of (m-M)o = 27.53 +/- 0.12 (corresponding to a distance of 3.2 +/- 0.2 Mpc), placing UGC 4483 within the NGC 2403 subgroup. We were able to measure properties of a previously-known young star cluster in UGC 4483, finding integrated magnitudes of V = 18.66 +/- 0.21 and I = 18.54 +/- 0.10 for the stellar contribution (integrated light minus Halpha and [OIII] contribution), corresponding to an age of ~10-15 Myr and initial mass of ~10^4 Msun. This is consistent with the properties of the cluster's brightest stars, which were resolved in the data for the first time. Finally, a numerical analysis of the galaxy's stellar content yields a roughly constant star formation rate of 1.3x10^-3 Msun/yr and mean metallicity of [Fe/H] = -1.3 dex from 15 Gyr ago to the present.
Keywords
Cite
@article{arxiv.astro-ph/0012471,
title = {The Stellar Content and Distance of UGC 4483},
author = {A. E. Dolphin and L. Makarova and I. D. Karachentsev and V. E. Karachentseva and D. Geisler and E. K. Grebel and P. Guhathakurta and P. W. Hodge and A. Sarajedini and P. Seitzer},
journal= {arXiv preprint arXiv:astro-ph/0012471},
year = {2015}
}
Comments
6 pages, accepted for publication in MNRAS