scholarly journals Abundance Ratios in Dwarf Elliptical Galaxies

2016 ◽  
Vol 11 (S321) ◽  
pp. 269-269
Author(s):  
Seyda Sen ◽  
Reynier F. Peletier ◽  
Elisa Toloba ◽  
Jaco J. Mentz
Keyword(s):  
Star Formation ◽  
Stellar Population ◽  
Population Analysis ◽  
Elliptical Galaxies ◽  
Virgo Cluster ◽  
Scaling Relations ◽  
Unusual Behaviour ◽  
Dwarf Elliptical Galaxies ◽  
Index Index ◽  
Star Formation Histories

AbstractThe aim of this study is to determine abundance ratios and star formation histories (SFH) of dwarf ellipticals in the nearby Virgo cluster. We perform a stellar population analysis of 39 dEs and study them using index-index and scaling relations. We find an unusual behaviour where [Na/Fe] is under-abundant w.r.t. solar while [Ca/Fe] is over-abundant.

scholarly journals Dwarf ellipticals in the eye of SAURON: dynamical & stellar population analysis in 3D

2014 ◽  
Vol 10 (S309) ◽  
pp. 161-162
Author(s):  
Agnieszka Ryś ◽  
Jesús Falcón-Barroso ◽  
Glenn van de Ven ◽  
Mina Koleva
Keyword(s):  
Star Formation ◽  
Stellar Population ◽  
Population Analysis ◽  
Secondary Star ◽  
La Palma ◽  
Angular Momenta ◽  
Star Formation Activity ◽  
Order Of Magnitude ◽  
Dwarf Elliptical Galaxies ◽  
Star Formation Histories

AbstractWe present the dynamical and stellar population analysis of 12 dwarf elliptical galaxies (dEs) observed using the SAURON IFU (WHT, La Palma). We demonstrate that dEs have lower angular momenta than their presumed late-type progenitors and we show that dE circular velocity curves are steeper than the rotation curves of galaxies with equal and up to an order of magnitude higher luminosity. Transformation due to tidal harassment is able to explain all of the above, unless the dE progenitors were already compact and had lower angular momenta at higher redshifts. We then look at the star formation histories (SFHs) of our galaxies and find that for the majority of them star formation activity was either still strong at a few Gyr of age or they experienced a secondary burst of star formation roughly at that time. This latter possibility would be in agreement with the scenario where tidal harassment drives the remaining gas inwards and induces a secondary star formation episode. Finally, one of our galaxies appears to be composed exclusively of an old population (≳12 Gyr). Combining this with our earlier dynamical results, we conclude that it either was ram-pressure stripped early on in its evolution in a group environment and subsequently tidally heated (which lowered its angular momentum and increased compactness), or that it evolved in situ in the cluster's central parts, compact enough to avoid tidal disruption.

scholarly journals 3D view on Virgo and field dwarf elliptical galaxies: late-type origin and environmental transformations

2012 ◽  
Vol 10 (H16) ◽  
pp. 334-334
Author(s):  
Agnieszka Ryś ◽  
Jesús Falcón-Barroso ◽  
Glenn van de Ven
Keyword(s):  
Large Scale ◽  
Stellar Population ◽  
Line Strength ◽  
Elliptical Galaxies ◽  
Formation Mechanisms ◽  
Population Parameters ◽  
Irregular Galaxies ◽  
Model Predictions ◽  
Dwarf Elliptical Galaxies ◽  
Star Formation Histories

AbstractIn our contribution we show the effects of environmental evolution on cluster and field dwarf elliptical galaxies (dEs), presenting the first large-scale integral-field spectroscopic data for this galaxy class. Our sample con sists of 12 galaxies and no two of them are alike. We find that the level of rotation is not tied to flattening; we observe kinematic twists; we discover large-scale kinematically-decoupled components; we see varying gradient s in line-strength maps: from nearly flat to strongly peaked in the center. The great variety of morphological, kinematic, and stellar population parameters seen in our data supports the claim that dEs are defunct dwarf spiral/irregular galaxies and points to a formation scenario that allows for a stochastic shaping of galaxy properties. The combined influence of ram-pressure stripping and harassment fulfills these requirements, still, the exact impact of the two is not yet understood. We further investigate the properties of our sample by performing a detailed comprehensive analysis of its kinematic, dynamical, and stellar population parameters. The combined knowledge of the dynamical properties and star-formation histories, together with model predictions for different formation mechanisms, will be used to quant itatively determine the actual transformation paths for these galaxies.

scholarly journals The ATLAS3D Project – XXX. Star formation histories and stellar population scaling relations of early-type galaxies

2015 ◽  
Vol 448 (4) ◽  
pp. 3484-3513 ◽  
Author(s):  
Richard M. McDermid ◽  
Katherine Alatalo ◽  
Leo Blitz ◽  
Frédéric Bournaud ◽  
Martin Bureau ◽  
...  
Keyword(s):  
Star Formation ◽  
Stellar Population ◽  
Scaling Relations ◽  
Early Type ◽  
Star Formation Histories

scholarly journals SFHs Across the Merging Disks of Arp 244 – from FUV to MIR

2009 ◽  
Vol 5 (S262) ◽  
pp. 454-455
Author(s):  
Hong-Xin Zhang ◽  
Yu Gao ◽  
Xu Kong
Keyword(s):  
Star Formation ◽  
Stellar Population ◽  
Population Analysis ◽  
Dust Emission ◽  
Close Encounter ◽  
Star Forming ◽  
Star Forming Regions ◽  
Loop Regions ◽  
Star Formation Histories ◽  
Multi Band

AbstractIncluding MIPS 24 μm dust emission in the multi-band stellar population analysis, we roughly constrain the star formation histories (SFHs) of MIPS 24 μm selected star-forming regions across the merging disks of the Antennae galaxies. While the overlap regions hold the highest ratios of young over intermediate populations, the western-loop regions have the highest ratios of intermediate to old populations. We find two sequential star formation (SF) paths in the overlap regions, which we interpret as the imprint of the interpenetrating process of the two merging disks following their second close encounter.

scholarly journals Substructure in Dwarf Galaxies

2004 ◽  
Vol 21 (4) ◽  
pp. 379-381
Author(s):  
Matthew Coleman
Keyword(s):  
Dark Matter ◽  
Star Formation ◽  
Large Scale ◽  
Stellar Population ◽  
Milky Way ◽  
Dwarf Galaxies ◽  
Tidal Interaction ◽  
Kinematic Evolution ◽  
Dark Material ◽  
Star Formation Histories

AbstractRecent years have seen a series of large-scale photometric surveys with the aim of detecting substructure in nearby dwarf galaxies. Some of these objects display a varying distribution of each stellar population, reflecting their star formation histories. Also, dwarf galaxies are dominated by dark matter, therefore luminous substructure may represent a perturbation in the underlying dark material. Substructure can also be the effect of tidal interaction, such as the disruption of the Sagittarius dSph by the Milky Way. Therefore, substructure in dwarf galaxies manifests the stellar, structural, and kinematic evolution of these objects.

Sign in / Sign up

Export Citation Format

Share Document