The Stellar Content and Distance of UGC 4483

A. E. Dolphin; L. Makarova; I. D. Karachentsev; V. E. Karachentseva; D. Geisler; E. K. Grebel; P. Guhathakurta; P. W. Hodge; A. Sarajedini; P. Seitzer

doi:10.1046/j.1365-8711.2001.04312.x

arXiv · astro-ph/0012471

The Stellar Content and Distance of UGC 4483

A. E. Dolphin·L. Makarova·I. D. Karachentsev·V. E. Karachentseva·D. Geisler·E. K. Grebel·P. Guhathakurta·P. W. Hodge·A. Sarajedini·P. Seitzer

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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.

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A. E. Dolphin, L. Makarova, I. D. Karachentsev, V. E. Karachentseva, D. Geisler, E. K. Grebel, P. Guhathakurta, P. W. Hodge, A. Sarajedini, P. Seitzer. 2000-12-22. The Stellar Content and Distance of UGC 4483. https://doi.org/10.1046/j.1365-8711.2001.04312.x

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