Collisional-like dissipation in collisionless plasma: MMS and kinetic simulations
Presentation Type
Talk
Presenter Format
In Person Meeting Talk
Topic
Dayside Science
Start Date
10-5-2022 2:30 PM
Abstract
Authors:
William H. Matthaeus, Riddhi Banyopadhyay,Yan Yang, and Tulasi Parashar, Alex Chasapis
Affiliations:
1 Department of Physics and Astronomy, Bartol Research Institute, University of Delaware, Newark, DE 19716
2 Department of Astronomical Sciences, Princeton University, Princeton NJ
3 LASP, University of Colorado Boulder, Boulder CO
Abstract:
When collisions are strong in a magnetized plasma, standard closures provide simple representations of dissipation in terms of coefficients of viscosity and resistivity. In the opposite limit of weak collisions, the same underlying physical effects that lead to dissipation are present, but the simple approximations to describe them, the closures, are not available in general. But how different are these relationships when collisions are absent? Here we inquire as to whether the collisionless case admits statistical relationships analogous to the viscous and resistive closures found in collisional plasma. We employ kinetic PIC simulation in two and a half and three dimensions, as well as MMS observations in the magnetosheath, to examine analogous viscous-like and resistive-like scalings in the weakly collisional regime.
Collisional-like dissipation in collisionless plasma: MMS and kinetic simulations
Authors:
William H. Matthaeus, Riddhi Banyopadhyay,Yan Yang, and Tulasi Parashar, Alex Chasapis
Affiliations:
1 Department of Physics and Astronomy, Bartol Research Institute, University of Delaware, Newark, DE 19716
2 Department of Astronomical Sciences, Princeton University, Princeton NJ
3 LASP, University of Colorado Boulder, Boulder CO
Abstract:
When collisions are strong in a magnetized plasma, standard closures provide simple representations of dissipation in terms of coefficients of viscosity and resistivity. In the opposite limit of weak collisions, the same underlying physical effects that lead to dissipation are present, but the simple approximations to describe them, the closures, are not available in general. But how different are these relationships when collisions are absent? Here we inquire as to whether the collisionless case admits statistical relationships analogous to the viscous and resistive closures found in collisional plasma. We employ kinetic PIC simulation in two and a half and three dimensions, as well as MMS observations in the magnetosheath, to examine analogous viscous-like and resistive-like scalings in the weakly collisional regime.
