Bibcode
Ryś, A.; Koleva, M.; Falcón-Barroso, J.; Vazdekis, A.; Lisker, Thorsten; Peletier, Reynier; van de Ven, Glenn
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 452, Issue 2, p.1888-1901
Advertised on:
9
2015
Citations
21
Refereed citations
21
Description
We present the stellar population analysis of a sample of 12 dwarf
elliptical galaxies, observed with the SAURON integral field unit, using
the full-spectrum fitting method. We show that star formation histories
(SFHs) resolved into two populations can be recovered even within a
limited wavelength range, provided that high signal-to-noise ratio (S/N)
data are used. We confirm that dEs have had complex SFHs, with star
formation extending to (more) recent epochs: for the majority of our
galaxies star formation activity was either still strong a few (≲5)
Gyr ago or they experienced a secondary burst of star formation roughly
at that time. This latter possibility is in agreement with the proposed
dE formation scenario where tidal harassment drives the gas remaining in
their progenitors inwards and induces a star formation episode. For one
of our field galaxies, ID 0918, we find a correlation between its
stellar population and kinematic properties, pointing to a possible
merger origin of its kinematically decoupled core. One of our cluster
objects, VCC 1431, appears to be composed exclusively of an old
population (≳10-12 Gyr). Combining this with our earlier dynamical
results, we conclude that the galaxy was either ram-pressure stripped
early on in its evolution in a group environment and subsequently
tidally heated, or that it evolved in situ in the cluster's central
parts, compact enough to avoid tidal disruption. These are only two of
the examples illustrating the SFH richness of these objects confirmed
with our data.
Related projects
Traces of Galaxy Formation: Stellar populations, Dynamics and Morphology
We are a large, diverse, and very active research group aiming to provide a comprehensive picture for the formation of galaxies in the Universe. Rooted in detailed stellar population analysis, we are constantly exploring and developing new tools and ideas to understand how galaxies came to be what we now observe.
Ignacio
Martín Navarro