Igor Chilingarian
Published 2006-11-29Version 1
This thesis presents observational studies of evolution of dwarf elliptical galaxies. dE's are numerically dominant population in clusters of galaxies, but their origin and evolution is a matter of debate. Several scenarios of gas removal from dE's exist: galactic winds, ram pressure stripping, gravitaional harassment. We present new method to estimate stellar population parameters and internal kinematics, based on fitting observed spectra in the pixel space by PEGASE.HR synthetic populations. We apply this technique to 3D-spectroscopic observations of dE galaxies in the Virgo cluster and nearby groups and multiobject spectroscopy of several dozens of dE's in the Abell 496 cluster. We present discovery of young nuclei in bright dE galaxies in the Virgo cluster. Based on the analysis of observational data we conclude that: (1) there is an evolutionary connection between dE's and dIrr's, (2) the most probable scenario of gas removal is ram pressure stripping by the intergalactic medium.
Comments: Full manuscript of the PhD thesis (revised version). Includes a short abstract in French. 107 pages, 28 figures, 12 tables. Defended on the 23rd of November, 2006 as a bilateral PhD between Moscow State University (Russia) and Universite Claude Bernard Lyon-1 (France). This is an unofficial English version used by referees and French members of the jury. Official version (Russian + French summary) is available at http://www.sai.msu.su/~chil/manuscript_fr.pdf
Stellar Populations of Dwarf Elliptical Galaxies: UBVRI Photometry of Dwarf Elliptical Galaxies in the Virgo Cluster
Ram pressure stripping and galaxy orbits: The case of the Virgo cluster
Is the shape of the luminosity profile of dwarf elliptical galaxies a useful distance indicator?
