Fine structure of an SBS line generated from spontaneous noise by quasimonochromatic pumping

Fourier analysis of the experimental results is used to show that the spectral line of the Stokes radiation, generated from spontaneous noise in stimulated Brillouin scattering, may consist of a superposition of one or several narrow spectral lines and background wings. The presence of narrow-band components of the spectrum may be the result of practically unavoidable loop-type feedback.