Events at Physics |
dissipation of the turbulence, and consequent conversion of turbulent
fluctuation energy to plasma heat, occurs at scales on which the plasma
dynamics is collisionless. Direct access to the near Earth solar wind provides a
unique opportunity to confront our understanding of the dynamics of kinetic
plasma turbulence, and its dissipation via collisionless damping mechanisms,
with in situ spacecraft measurements. Significant effort has recently been
focused on employing the gyrokinetic formalism to study the dissipation of
turbulence in the solar wind, taking advantage of sophisticated numerical
techniques developed for use in the fusion community. Here I will report on
some of the most recent successes of this effort, in particular the first threedimensional,
nonlinear gyrokinetic simulation of plasma turbulence resolving
scales from the ion to electron gyroradius with a realistic mass ratio, where all
damping is provided by resolved physical mechanisms. Complementing this
theoretical and numerical research program are experiments on the Large
Plasma Device (LAPD) at UCLA to measure the nonlinear interactions between
counterpropagating Alfven waves, the fundamental building block of Alfvenic
plasma turbulence.