%0 Journal Article %T Schechter Function Model for the QSO Luminosity Function from the SDSS DR7 %A Salam Ajitkumar Singh %A I. Ablu Meitei %A K. Yugindro Singh %J International Journal of Astronomy and Astrophysics %P 247-253 %@ 2161-4725 %D 2016 %I Scientific Research Publishing %R 10.4236/ijaa.2016.63020 %X A study of the optical luminosity function of Quasi Stellar Objects (QSOs) and its evolution with redshift is carried out using the data from the Sloan Digital Sky Survey Data Release Seven (SDSS DR7). It is shown that the observed QSO luminosity function is well fitted by a Schechter function model of the form \"\", where \"\" is the break or characteristic luminosity with luminosity evolution characterized by a second order polynomial in red shift. The best fit parameters are determined by using the Levenberg-Marquardt method of nonlinear least square fit. %K Galaxies: Active %K Quasars: General %K Galaxies: Luminosity Function %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=69666