Bibcode
Janz, J.; Laurikainen, E.; Lisker, T.; Salo, H.; Peletier, R. F.; Niemi, S.-M.; Toloba, E.; Hensler, G.; Falcón-Barroso, J.; Boselli, A.; den Brok, M.; Hansson, K. S. A.; Meyer, H. T.; Ryś, A.; Paudel, S.
Bibliographical reference
The Astrophysical Journal, Volume 786, Issue 2, article id. 105, 33 pp. (2014).
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5
2014
Journal
Citations
68
Refereed citations
65
Description
The fraction of star-forming to quiescent dwarf galaxies varies from
almost infinity in the field to zero in the centers of rich galaxy
clusters. What is causing this pronounced morphology-density relation?
What do quiescent dwarf galaxies look like when studied in detail, and
what conclusions can be drawn about their formation mechanism? Here we
study a nearly magnitude-complete sample (–19 < Mr
<–16 mag) of 121 Virgo cluster early types with deep
near-infrared images from the SMAKCED project. We fit two-dimensional
models with optional inner and outer components, as well as bar and lens
components (in ~15% of the galaxies), to the galaxy images. While a
single Sérsic function may approximate the overall galaxy
structure, it does not entirely capture the light distribution of
two-thirds of our galaxies, for which multicomponent models provide a
better fit. This fraction of complex galaxies shows a strong dependence
on luminosity, being larger for brighter objects. We analyze the global
and component-specific photometric scaling relations of early-type dwarf
galaxies and discuss similarities with bright early and late types. The
dwarfs' global galaxy parameters show scaling relations that are similar
to those of bright disk galaxies. The inner components are mostly fitted
with Sérsic n values close to 1. At a given magnitude, they are
systematically larger than the bulges of spirals, suggesting that they
are not ordinary bulges. We argue that the multicomponent structures in
early-type dwarfs are mostly a phenomenon inherent to the disks and may
indeed stem from environmental processing.
Based on observations collected at the European Organisation for
Astronomical Research in the Southern Hemisphere, Chile, under program
IDs 064.N-0288 and 085.B-0919.
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