Bibcode
Yildirim, Akin; van de Ven, Glenn; Naab, Thorsten; McDermid, Richard; Krajnović, Davor; Falcón-Barroso, J.; de Zeeuw, Tim; Cappellari, Michele; Emsellem, Eric; Kuntschner, Harald; van den Bosch, Remco; Weijmans, Anne-Marie; Boardman, N. F.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 471, Issue 4, p.4005-4026
Advertised on:
11
2017
Citations
35
Refereed citations
31
Description
We observed 12 nearby H i-detected early-type galaxies (ETGs) of stellar
mass ˜1010 M⊙ ≤ M* ≤
˜1011 M⊙ with the Mitchell
Integral-Field Spectrograph, reaching approximately three half-light
radii in most cases. We extracted line-of-sight velocity distributions
for the stellar and gaseous components. We find little evidence of
transitions in the stellar kinematics of the galaxies in our sample
beyond the central effective radius, with centrally fast-rotating
galaxies remaining fast-rotating and centrally slow-rotating galaxies
likewise remaining slow-rotating. This is consistent with these galaxies
having not experienced late dry major mergers; however, several of our
objects have ionized gas that is misaligned with respect to their stars,
suggesting some kind of past interaction. We extract Lick index
measurements of the commonly used H β, Fe5015, Mg b, Fe5270 and
Fe5335 absorption features, and we find most galaxies to have flat H
β gradients and negative Mg b gradients. We measure gradients of
age, metallicity and abundance ratio for our galaxies using spectral
fitting, and for the majority of our galaxies find negative age and
metallicity gradients. We also find the stellar mass-to-light ratios to
decrease with radius for most of the galaxies in our sample. Our results
are consistent with a view in which intermediate-mass ETGs experience
mostly quiet evolutionary histories, but in which many have experienced
some kind of gaseous interaction in recent times.
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