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The M31 Dwarf Spheroidal Companion And V: g', r', and i' Imaging with GMOS on Gemini North

T. J. Davidge·G. S. Da Costa·I. Jorgensen·J. R. Allington-Smith
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Abstract

g', r', and i' images obtained with the Gemini Multi-Object Spectrograph (GMOS) on Gemini North are used to investigate the metallicity and stellar content of the M31 dwarf spheroidal companion galaxy And V. Red giant branch (RGB) stars are traced out to radii in excess of 126 arcsec from the galaxy center, indicating that And V extends over a diameter approaching 1 kpc. The mean g'-i' color of the RGB does not change with radius. Based on the slope of the RGB in the (i', g'-i') color-magnitude diagram we conclude that [Fe/H] = -2.2 +/- 0.1. This metallicity is lower than earlier estimates, and places And V squarely on the relation between metallicity and integrated brightness defined by other dwarf spheroidal and dwarf elliptical galaxies. We also fail to find a statistically significant population of luminous asymptotic giant branch stars near the center of the galaxy.

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T. J. Davidge, G. S. Da Costa, I. Jorgensen, J. R. Allington-Smith. 2002-07-04. The M31 Dwarf Spheroidal Companion And V: g', r', and i' Imaging with GMOS on Gemini North. https://arxiv.org/abs/astro-ph/0207120

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