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arXiv · astro-ph/0701842

Kinematics and stellar populations of the dwarf elliptical galaxy IC 3653

Igor Chilingarian·Philippe Prugniel·Olga Sil'chenko·Victor Afanasiev
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Abstract

We present the first 3D observations of a diffuse elliptical galaxy (dE). The good quality data (S/N up to 40) reveal the kinematical signature of an embedded stellar disc, reminiscent of what is commonly observed in elliptical galaxies, though similarity of their origins is questionable. Colour map built from HST ACS images confirms the presence of this disc. Its characteristic scale (about 3 arcsec = 250 pc) is about a half of galaxy's effective radius, and its metallicity is 0.1-0.2 dex larger than the underlying population. Fitting the spectra with synthetic single stellar populations (SSP) we found an SSP-equivalent age of 5 Gyr and nearly solar metallicity [Fe/H]=-0.06 dex. We checked that these determinations are consistent with those based on Lick indices, but have smaller error bars. The kinematical discovery of a stellar disc in dE gives additional support to an evolutionary link from dwarf irregular galaxies due to stripping of the gas against the intra-cluster medium.

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Igor Chilingarian, Philippe Prugniel, Olga Sil'chenko, Victor Afanasiev. 2007-01-30. Kinematics and stellar populations of the dwarf elliptical galaxy IC 3653. https://doi.org/10.1111/j.1365-2966.2007.11549.x

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