Redshift modification of pulsars and magnetars by relativistic plasmas and vacuum polarization

The redshifts of emissions from pulsars and magnetars consist of two components: gravitational and non-gravitational redshifts. The latter results from the electromagnetic and kinetic effects of relativistic plasmas, characterized by refractive indices and streaming velocities of the media, respectively. The vacuum polarization effect induced by strong magnetic fields can modify the refractive indices of the media, and thus leads to a modification to the redshifts. The Gordon effective metric is introduced to study the redshifts of emissions. The modification of the gravitational redshift, caused by the effects of relativistic plasmas and vacuum polarization, is obtained.