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Young Nuclei in Dwarf Elliptical Galaxies

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

We report discovery of young embedded structures in three diffuse elliptical galaxies (dE) in the Virgo cluster: IC 783, IC 3468, and IC 3509. We performed 3D spectroscopic observations of these galaxies using the MPFS spectrograph at the Russian 6-m telescope, and obtained spatially resolved distributions of kinematical and stellar population parameters by fitting high-resolution PEGASE.HR synthetic single stellar populations (SSP) in the pixel space. In all three galaxies, the luminosity weighted age of the nuclei, about 4 Gyr, is considerably younger than population in the outer regions of the galaxies. We discuss two possibilities to acquire the observed structures -- dissipative merger event and different ram pressure stripping efficiency during two consequent crossings of the Virgo cluster centre.

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Igor Chilingarian, Olga Sil'chenko, Victor Afanasiev, Philippe Prugniel. 2006-11-28. Young Nuclei in Dwarf Elliptical Galaxies. https://doi.org/10.1134/s1063773707050027

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