Natural fluctuations of radiation emitted from a traveling-wave laser in the direction opposite to the strong field

A theoretical analysis is made of fluctuations of the radiation emitted from a single-mode traveling-wave laser with homogeneous broadening of the transition line in the direction opposite to the strong field. Allowance is made for the distributed nature of the laser parameters. An expression is derived for the spectral density of the field fluctuations. A comparison is made with the experiments.