Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2011-01-21
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
in press
Scientific paper
10.1111/j.1365-2966.2011.18926.x
There are strong correlations between the three structural properties of elliptical galaxies -- stellar mass, velocity dispersion and size -- in the form of a tight "fundamental plane" and a "scaling relation" between each pair. Major mergers of disk galaxies are assumed to be a mechanism for producing ellipticals, but semi-analytic galaxy formation models (SAM) have encountered apparent difficulties in reproducing the observed slope and scatter of the size-mass relation. We study the scaling relations of merger remnants using progenitor properties from two SAMs. We apply a simple merger model that includes gas dissipation and star formation based on theoretical considerations and simulations. Combining the SAMs and the merger model allows calculation of the structural properties of the remnants of major mergers that enter the population of elliptical galaxies at a given redshift. Without tuning the merger model parameters for each SAM, the results roughly match the slope and scatter in the observed scaling relations and their evolution in the redshift range $z=0-3$. Within this model, the observed scaling relations, including the tilt of the fundamental plane relative to the virial plane, result primarily from the decrease of gas fraction with increasing progenitor mass. The scatter in the size-mass relation of the remnants is reduced from that of the progenitors because of a correlation between progenitor size and gas fraction at a given mass.
Covington Matthew D.
Croton Darren J.
Dekel Avishai
Porter Alan L.
Primack Joel R.
No associations
LandOfFree
The Role of Dissipation in the Scaling Relations of Cosmological Merger Remnants 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 The Role of Dissipation in the Scaling Relations of Cosmological Merger Remnants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Role of Dissipation in the Scaling Relations of Cosmological Merger Remnants will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-642240