The Role of Vesc in Early Type Galaxy Evolution

Scott, N., Cappellari, M., Davies, R., Bacon, R., T. de Zeeuw, P., Emsellem, E., Falcón-Barroso, J., Krajnovic, D., Kuntschner, H., M. McDermid, R., Peletier, R. F., Pipino, A., Sarzi, M., Van den Bosch, R., van de Ven, G. & van Scherpenzeel, E., Jan-2010, In : Bulletin of the American Astronomical Society. 42, p. 551

Research output: Contribution to journalArticleAcademicpeer-review

  • Nicholas Scott
  • M. Cappellari
  • R Davies
  • R. Bacon
  • P. T. de Zeeuw
  • E. Emsellem
  • J. Falcón-Barroso
  • D. Krajnovic
  • H. Kuntschner
  • R. M. McDermid
  • R.F. Peletier
  • A. Pipino
  • M. Sarzi
  • R. Van den Bosch
  • G. van de Ven
  • E. van Scherpenzeel
How the stellar mass of early-type galaxies is assembled remains an open question. Are the stars formed in situ, possibly triggered by merger events, or do they form in smaller systems before being added to the host galaxy through mergers? Using the SAURON sample of local early-type galaxies combined with dynamical modelling we searched for correlations between dynamical and stellar population parameters of early-type galaxies in order to address this question. The most striking correlation is that between the local Mgb line strength and the local gravitational potential, expressed here in terms of the local escape velocity. The Mgb-Vesc relation is extremely tight, while most significantly being the same both between different galaxies and within individual galaxies. Such a tight local and global relation can be used to constrain the amount of star formation associated with a merger event in order for a galaxy to remain on the relation. When we transform to single stellar population (SSP) parameters we find that this local and global behaviour is reproduced by the combination: log (Vesc/500 kms-1) = 0.85[Z/H] + 0.43(t/Gyrs). That a combination of age and metallicity is tightly correlated with the local Vesc is somewhat surprising, and may indicate a weakness in the SSP models or a `conspiracy’ in age and metallicity.
Original languageEnglish
Pages (from-to)551
JournalBulletin of the American Astronomical Society
Publication statusPublished - Jan-2010
EventAmerican Astronomical Society, AAS Meeting #215, #363.02 - Washington D.C., United States
Duration: 3-Jan-20107-Jan-2010


American Astronomical Society, AAS Meeting #215, #363.02


Washington D.C., United States

Event: Conference

ID: 38626059