Raman scattering of the synchrotron self-absorbed radiation in accretion discs

Abstract

The quasar non-thermal continuum in the radio region can undergo Raman scattering in the accretion disc plasma around the central black hole provided that the frequency and the wave vector matching and the threshold conditions are satisfied. The scattered radiation has a frequency ω0/2 ≡ ωp where ω0 is the frequency of the incident radiation and ωp is the electron plasma frequency. The spectral shape of the scattered radiation is significantly different from that of the incident radiation. It is proposed that the observed spectral shape of the radio radiation may be accounted for by including the effects of Raman scattering.