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arXiv · astro-ph/0105435

Cold gas in elliptical galaxies

A. Georgakakis·A. M. Hopkins·A. Caulton·T. Wiklind·A. I. Terlevich·D. A. Forbes
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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.

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A. Georgakakis, A. M. Hopkins, A. Caulton, T. Wiklind, A. I. Terlevich, D. A. Forbes. 2001-05-24. Cold gas in elliptical galaxies. https://doi.org/10.1111/j.1365-2966.2001.04677.x

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