Narrow [O III] emission lines as a potential proxy for the evolutionary stage of quasars

Zhi-fu Chen, Zhe-Geng Chen, Xing-long Peng +1

Radio spectral shape of quasars can provide insight into the ages of quasars. We have compiled data for 1804 quasars with $z\lesssim 1$ from the Sloan Digital Sky Survey (SDSS). Add…