Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2010-05-14
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
Accepted for publication in MNRAS 2010 May 08; 21 pages, 33 figures and 6 tables; High resolution version http://star.herts.
Scientific paper
Nuclear Stellar Disks (NSDs), of a few tens to hundreds of parsec across, are a common and yet poorly studied feature of early-type galaxies. Still, such small disks represent a powerful tool to constrain the assembling history of galaxies, since they can be used to trace to the epoch when galaxies experienced their last major merger event. By studying the fraction and stellar age of NSDs it is thus possible to test the predictions for the assembly history of early-type galaxies according the current hierarchical paradigm for galaxy formation. In this paper we have produced the most comprehensive census of NSDs in nearby early-type galaxies by searching for such disks in objects within 100 Mpc and by using archival images from the Hubble Space Telescope. We found that NSDs are present in approximately 20% of early-type galaxies, and that the fraction of galaxies with NSDs does not depend on their Hubble type nor on their galactic environment, whereas the incidence of NSDs appears to decline in the most massive systems. Furthermore, we have separated the light contribution of twelve such disks from that of their surrounding stellar bulge in order to extract their physical properties. This doubles the number of decomposed NSDs and although the derived values for their central surface brightness and scale-length are consistent with previous studies they also give a hint of possible different characteristics due to different formation scenario between nuclear disks and other kinds of large galactic disks.
Dotti Massimo
Khochfar Sadegh
Ledo H. R.
Morelli Lorenzo
Sarzi Marc
No associations
LandOfFree
A Census of Nuclear Stellar Disks in Early-type Galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Census of Nuclear Stellar Disks in Early-type Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Census of Nuclear Stellar Disks in Early-type Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-519614