Bibcode
Ruiz, P.; Trujillo, I.; Mármol-Queraltó, E.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 442, Issue 1, p.347-360
Advertised on:
7
2014
Citations
21
Refereed citations
19
Description
Using the spectroscopic New York University Value-Added Galaxy Catalogue
and the photometric photo-z catalogues of the Sloan Digital Sky Survey
Data Release 7, we have explored the satellite distribution around
˜1000 massive (M⋆ ≳ 2 × 1011
M⊙) visually classified elliptical galaxies down to a
satellite mass ratio of 1:400 (i.e. 5 × 108 ≲
Msat ≲ 2 × 1011 M⊙). Our
host galaxies were selected to be representative of a mass complete
sample. The satellites of these galaxies were searched within a
projected radial distance of 100 kpc to their hosts. We have found that
only 20-23 per cent of the massive ellipticals have at least a satellite
down to a mass ratio 1:10. This number increases to 45-52 per cent if we
explore satellites down to 1:100 and is >60-70 per cent if we go
further down to 1:400. The average projected radial distance of the
satellites to their hosts for our whole sample down to 1:400 is
˜59 kpc (which can be decreased at least down to 50 kpc if we
account for incompleteness effects). The number of satellites per galaxy
host only increases very mildly at decreasing the satellite mass. The
fraction of mass which is contained in the satellites down to a mass
ratio of 1:400 is 8 per cent of the total mass contained by the hosts.
Satellites with a mass ratio from 1:2 to 1:5 (with ˜28 per cent of
the total mass of the satellites) are the main contributor to the total
satellite mass. If the satellites eventually infall into the host
galaxies, the merger channel will be largely dominated by satellites
with a mass ratio down to 1:10 (as these objects have 68 per cent of the
total mass in satellites).
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