Cold gas in elliptical galaxies
Abstract
We explore the evolution of the cold gas (molecular and neutral hydrogen) of elliptical galaxies and merger remnants ordered into a time sequence on the basis of spectroscopic age estimates. We find that the fraction of cold gas in early merger remnants decreases significantly for ~1-2 Gyr, but subsequent evolution toward evolved elliptical systems sees very little change. This trend can be attributed to an initial gas depletion by strong star-formation which subsequently declines to quiescent rates. This explanation is consistent with the merger picture for the formation of elliptical galaxies. We also explore the relation between HI-to-H2 mass ratio and spectroscopic galaxy age, but find no evidence for a statistically significant trend. This suggests little net HI to H2 conversion for the systems in the present sample.
Cite
@article{arxiv.astro-ph/0105435,
title = {Cold gas in elliptical galaxies},
author = {A. Georgakakis and A. M. Hopkins and A. Caulton and T. Wiklind and A. I. Terlevich and D. A. Forbes},
journal= {arXiv preprint arXiv:astro-ph/0105435},
year = {2008}
}
Comments
11 pages, 6 figures, accepted for publication by MNRAS