The AGN Population and Luminosity Function in the Sloan Digital Sky Survey

Lei Hao
Princeton University

4:15-5:15 Tuesday April 29, 2003

Abstract

We search for Active Galactic Nuclei in the Sloan Digital Sky Survey (SDSS) spectroscopic sample based on their emission line characteristics. The large number and high S/N galaxy spectra observed by the SDSS allow us to form a large uniform AGN sample. Thus far over 3000 broad-line AGNs and 3000 narrow-line AGNs have been identified. The AGN H_alpha FWHM distribution is bimodal with two populations separated at about 1200km/s. Therefore broad-line AGNs are identified as the galaxies with FWHM(Halpha)>1200km/s. Narrow-line AGNs are identified using the emission line ratio diagnostic diagrams. After evaluating the detection probability function for each AGN using Monte-Carlo simulation, we obtained the luminosity function for both Seyfert 1s and Seyfert 2s. The number density of Seyfert 1s is about the same as that of Seyfert 2s at low luminosity, but outnumber Seyfert 2s toward high luminosity. Detailed tests of the luminosity function are conducted and we show strong evidence that the nuclear luminosity is not strongly correlated with the host galaxy luminosity.

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