Cerenkov Line Radiation — a New Interpretation of the Emission Lines of Quasars

Abstract

An electron moving at relativistic speed β = v/c in a medium of refractive index n will emit Cerenkov radiation if βn> 1, and for a given β, this condition may be satisfied over some small wavelength range next to atomic lines, under favourable physical conditions. The radiation so produced will than look like broad lines, asymmetrical in shape and characteristically displaced from the atomic line. For this reason, J.H. You called this radiation the “Cerenkov line radiation”. The necessary physical conditions are that there should be a sufficient number of the atom in question and of the relativistic electrons.