Phase space eigenfunctions for continuum kinetic simulations

In weak turbulence the linear eigenfunctions contain most of the fluctuation energy, and this is also true for phase space turbulence in collisionless plasma. In this work, phase space eigenfunctions are studied in the unmagnetized and strongly magnetized regimes. Further, the nonlinear structures, or phase space vortices, corresponding to the linear eigenfunctions are studied. The phase space cascade responsible for anomalous dissipation is composed of such phase space vortices. Here nonlinear structures are presented for Weibel modes of the bi-Maxwellian and electron cyclotron instabilities in loss-cone distributions. In addition, ensembles of randomly phased eigenfunctions are utilized as initial conditions for Vlasov and quasilinear simulations. Such simulations are presented for Langmuir and Weibel turbulence in two-dimensional configuration space. The insights gained from this particular work are discussed in the context of cross-field anomalous resistivity in hot Z-pinch plasmas.