A census of nuclear stellar discs in early-type galaxies
View/ Open
Author
Ledo, H.R.
Sarzi, M.
Dotti, M.
Khochfar, S.
Morelli, L.
Attention
2299/5422
Abstract
Nuclear stellar discs (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 discs 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 to 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 discs in objects within 100 Mpc and by using archival images from the Hubble Space Telescope. We found that NSDs are present in approximately 20 per cent of early-type galaxies, and that the fraction of galaxies with NSDs depends neither 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 12 such discs 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 scalelength are consistent with previous studies, they also give a hint of possible different characteristics due to different formation scenario between nuclear discs and other kinds of large galactic discs.
Publication date
2010Published in
Monthly Notices of the Royal Astronomical SocietyPublished version
https://doi.org/10.1111/j.1365-2966.2010.16990.xOther links
http://hdl.handle.net/2299/5422Metadata
Show full item recordRelated items
Showing items related by title, author, creator and subject.
-
The H alpha galaxy survey. I. The galaxy sample, H alpha narrow-band observations and star formation parameters for 334 galaxies
James, P.A.; Shane, N.S.; Beckman, J.E.; Cardwell, A.; Collins, C.A.; Etherton, J.; de Jong, R.S.; Fathi, K.; Knapen, J.; Peletier, R.F.; Percival, S.M.; Pollacco, D.L.; Seigar, M.S.; Stedman, S. (2004)We discuss the selection and observations of a large sample of nearby galaxies, which we are using to quantify the star formation activity in the local Universe. The sample consists of 334 galaxies across all Hubble types ... -
On the Key Processes that Drive Galaxy Evolution: the Role of Galaxy Mergers, Accretion, Local Environment and Feedback in Shaping the Present-Day Universe
Martin, Garreth (2019-07-17)The study of galaxy evolution is a fundamental discipline in modern astrophysics, dealing with how and why galaxies of all types evolve over time. The diversity of present-day galaxies is a reflection of the processes ... -
The Physical Processes that Drive Galaxy Evolution - from Massive Galaxies to the Dwarf Regime
Jackson, Ryan (2021-09-25)The study of galaxy formation and evolution is a cornerstone in astrophysics, as galaxies connect together all scales of the Universe. The physical processes that govern galaxies therefore needs to be fully understood if ...