Bicoherence in the magnetised plasma of the Thorello device

Experimental investigation of magnetised plasma turbulence is actively pursued in fusion aimed as well as in basic plasma physics toroidal devices. Turbulence can be characterized through the nonlinear interaction between Fourier components and bispectral analysis is one of the techniques to investigate the wave–wave couplings and the interactions between fluctuations. Here this analysis has been applied to the experimental data of plasma parameters fluctuations of a turbulent, low beta, low temperature plasma with a simply magnetised torus configuration. Reported experiments have been performed in the Thorello device, operating at the University of Milano-Bicocca. In the paper we discuss the bicoherence measured in the full 2D poloidal section of the decvice, identifying the different regions and correlating bicoherence with other turbulence properties.