Spectral polarization features of the macroscopic manifestation of parity violation in gaseous media

A formalism based on macroscopic Maxwell equations is developed for the case of media with violations of the space symmetry and time reversal. It is demonstrated that the parity violation in a medium is equivalent to the manifestation of spatial dispersion and natural optical activity. The proposed formalism makes it possible to uniquely calculate the macroscopic parameters of equations in terms of the microscopic theory. The parameters of gyrotropy and dichroism of a gaseous medium are determined within a model describing an interaction of resonance radiation with transitions to states that have different parities and are mixed by a weak interaction of an electron with the nucleus of the atom. It is established that, in the range of the resonance with a magnetic dipole transition, the effect of parity violation is enhanced as a result of the considerable difference between the natural broadenings of the electric and magnetic dipole transitions. This enhancement is suppressed when the dominant Doppler broadening of the atomic transitions is taken into account. It is shown that, owing to the unitarity of the weak interaction, the effects of parity violation are alternating functions of the radiation frequency and are integrally absent in the entire spectrum.