Black Hole Masses of Weak Emission Line Quasars Based on the Continuum Fit Method

Abstract

We studied optical-ultraviolet spectral energy distribution of 10 weak emission-line quasars (WLQs) that lie at redshifts z  = 0.19 and 1.43 <  z  < 3.48. The theoretical models of their accretion disk continua are created based on the Novikov–Thorne equations. It allows us to estimate masses of their supermassive black holes ( ) and accretion rates. We determined the virial factor for WLQs and note its anticorrelation with the FWHM of the H β emission line ). By comparison with the previously estimated BH masses, the underestimation of is noticed with a mean factor of 4–5, which depends on the measured full width. We proposed a new formula to estimate in WLQs based on their observed (H β ) and luminosities at 5100 Å. In our opinion, WLQs are also normal quasars visible in a reactivation stage.