Problem: the best UV fit to the spectra has a deficit of ionizing photons (to reproduce the spectral emission of high ionization lines) and on the other hand, the Far-UV steepening is not well explained by accretion disk models. The composite spectrum of 184 quasars by Telfer et al. (2002) presents prominent continuum steepening around 1,100 A, in which the powerlaw index changes from approximately -0.75 (near UV) to -1.6 (far UV).
Aim: Show that the UV break seen in 5 individual quasar spectra of intermediate redshift can be reproduced by a accretion disk model with 2 component: reflecting clouds and reflecting occulted disk (Lawrence 2014). We constructed the UV and X-ray energy distributions for 5 quasars. The data were obtained from HST and Chandra repository.
Enviado por jafet.unam@gmail.com, 2019 Oct