Coherent structures in a turbulent environment.

A systematic method is proposed for the determination of the statistical properties of a field consisting of a coherent structure interacting with turbulent linear waves. The explicit expression of the generating functional of the correlations is obtained, performing the functional integration on a neighborhood in the function space around the soliton. The results show that the non-Gaussian fluctuations observed in the plasma edge can be explained by the intermittent formation of nonlinear coherent structures.