{
  "id": "astro-ph/9808325",
  "version": "v1",
  "published": "1998-08-28T09:16:52.000Z",
  "updated": "1998-08-28T09:16:52.000Z",
  "title": "The Formation History of Early-Type Galaxies: An Observational Perspective",
  "authors": [
    "Richard G. Bower",
    "Ale Terlevich",
    "Tadayuki Kodama",
    "Nelson Caldwell"
  ],
  "comment": "to appear in Star Formation in Early-Type Galaxies, ASP Conf. Ser., eds. P. Carral & J. Cepa; paspconf.sty LaTeX, 16 pages, 7 figures",
  "categories": [
    "astro-ph"
  ],
  "abstract": "This talk investigates the formation of early-type galaxies from a deliberately observational view point. I begin by reviewing the conclusions that can be reached by comparing the detailed properties of galaxies in present-day clusters, focusing on the colour-magnitude relation in particular. The overriding picture is one of homogeneity, implying a remarkable uniformity in the formation of these galaxies. This picture contrasts with the increasing activity seen in clusters as a function of redshift, creating an apparent paradox been the obvious diversity of star formation histories in distant cluster galaxies and their uniformity in local systems. A resolution is feasible so long as star formation occurs over an extended epoch. In addition to placing limits on variations in star formation history the existence of a tight `fundamental relations', such as the colour-magnitude relation, can be used to investigate galaxy mergers and to set limits on the degree to which present-day clusters galaxies are built by combining systems of stars formed in smaller units. The final part of this talk turns to early-type galaxies in the field, and tries to apply the same techniques that have been successful in clusters. This is an emerging field in which appropriate data-sets are only just becoming available; however, comparison of the formation histories of galaxies in a wide variety of environments is key to distinguishing between the Classical and Hierarchical models for galaxy formation.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1998-08-28T09:16:52.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "early-type galaxies",
      "observational perspective",
      "star formation history",
      "colour-magnitude relation",
      "present-day clusters galaxies"
    ],
    "note": {
      "typesetting": "LaTeX",
      "pages": 16,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 483372
    }
  }
}