Nonlinear interactions of ion acoustic waves explored using fast imaging decompositions

Fast camera imaging is used to study ion acoustic waves propagating azimuthally in a magnetized plasma column. The high-speed image sequences are analyzed using proper orthogonal decomposition and 2D Fourier transform, allowing evaluate the assets differences of both techniques. spatiotemporal features extracted from images, which highlight energy exchanges between modes. Growth rates modes reconstructed temporal evolution modes, revealing influence ion-neutral collisions as pressure increases. Finally, nonlinear interactions bicoherence computations, they show importance with azimuthal wave numbers m, m −1, an integer.