摘要
A nonlinear fluid description for the parameter processes has been derived.The linear instability analyses about three wave mixing process ω_(0)→ω_(s1)→ω_(s2) and four wave scattering process ω_(0)→ω_(s)+ω_(p1)+ω_(p2) have been made.Correspondent backward or side scattering light waves emitted from mentioned processes may provide valuable information for the diagnostic of plasma parameters.