Electronic Broadening operator for relativistic plasmas

In this work we review some aspects of the semiclassical dipole impact approximation for isolated ion lines in relativistic plasma. Mainly we focuss our work on the collision operator for relativistic electrons. In this case, the electron trajectory around a positive charge in the plasma differs drastically from those known earlier as hyperbolic. The effect of this difference on the collision operator is discussed with respect the various plasma conditions. Some theoretical and practical aspects of lines -shape calculations are discussed. Detailed calculations are performed for the collision operator in the semiclassical (dipole) impact approximation.