  A generalized Wigner-Moyal statistical theory of radiation is used to obtain
a general dispersion relation for Stimulated Brillouin Scattering (SBS) driven
by a broadband radiation field with arbitrary statistics. The monochromatic
limit is recovered from our general result, reproducing the classic
monochromatic dispersion relation. The behavior of the growth rate of the
instability as a simultaneous function of the bandwidth of the pump wave, the
intensity of the incident field and the wave number of the scattered wave is
further explored by numerically solving the dispersion relation. Our results
show that the growth rate of SBS can be reduced by 1/3 for a bandwidth of 0.3
nm, for typical experimental parameters.
