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Home List of Titles Formation and evolution of red Hdelta-strong galaxies in distant clusters: two different evolutionary paths to S0 galaxies?
Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/55935
- Formation and evolution of red Hdelta-strong galaxies in distant clusters: two different evolutionary paths to S0 galaxies?
- Shioya, Yasuhiro; Bekki, Kenji; Couch, Warrick J.
- We numerically investigate the spectrophotometric evolution of galaxies with a variety of different star formation histories and degrees of dust extinction in order to elucidate the origin of the 'red Hδ-strong' (RHDS) galaxies - characterized by strong [EW(Hδ) > 3 Å] Balmer line absorption but with colors as red as the dormant E/S0 systems - first observed in distant clusters of galaxies. Specifically, we investigate the evolution in the [(B-R), EW(Hδ)]-plane of two different galaxy models: a 'truncation' model in which a galaxy with a declining star formation rate (typical of a normal spiral) has its star formation abruptly truncated, and a 'starburst' model in which a galaxy undergoes a secondary burst of star formation that is abruptly halted. This leads to the following three main results: (1) Both models pass through the zone inhabited by the RHDS galaxies in this plane, but the 'truncation' models cannot explain the most extreme cases, which have EW(Hδ) > 6 Å. (2) The reddest RHDS galaxies can only be explained by 'truncation' or 'starburst' models that have very heavy dust extinction (Av > 0.5 mag). (3) Irrespective of whether dust effects are included, the 'truncation' models are incapable of reproducing the very blue (B-R < 1.6) analogs of the RHDS galaxies. By comparing these results with recent Hubble Space Telescope-based morphological and ground-based spectroscopic studies of distant cluster galaxies, we propose that there are two possible different evolutionary paths for the transformation of cluster spirals into S0 galaxies.
- Publication type
- Journal article
- Astrophysical Journal, Vol. 601, no. 2 (Feb 2004), pp. 654-665
- Publication year
- FOR Code(s)
- 0201 Astronomical and Space Sciences
- Clusters; Galaxy formation; H delta; HST; Hubble Space Telescope; Interactions; ISM; Structure; RHDS
- University of Chicago Press
- Publisher URL
- Copyright © 2004 The American Astronomical Society. All rights reserved. Publisher does not support archiving of either the postprint (final, revised accepted draft) or published version of full text in institutional repositories.
- Peer reviewed