to IAU
Symposium 241

Abstract details

Post-starburst stellar populations in SDSS galaxies
Vivienne Wild, Guinevere Kauffmann, Tim Heckman

Abstract
There has been much recent interest in post-starburst (PSB) stellar populations, in particular regarding a possible connection to Active Galactic Nuclei (AGN). PSB populations are characterized by strong Balmer absorption lines, however, recent studies often employ the H$\delta$ line alone. I will present a new method, in which stellar population synthesis models play an integral role, which exploits the entire 3750-4150\AA\ spectral range to recover the recent star formation history of integrated stellar populations. Particular advantages of this method are the greatly improved SNR, beneficial for higher redshift galaxy surveys, and the identification of PSB and starburst galaxies through their stellar continuum alone, thus avoiding the problem of AGN contamination of emission lines. We apply this method to the spectra of high mass, high velocity dispersion, z<0.08 SDSS galaxies. We study trends of burst strength and time of last burst in the galaxy bulges with AGN fraction, AGN luminosity and galaxy morphology. The project makes extensive use of VO databases, and isolates some discrepancies between population synthesis models and the SDSS data.