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Title: Whistler turbulence heating of electrons and ions: Three-dimensional particle-in-cell simuations

In this study, the decay of whistler turbulence in a collisionless, homogeneous, magnetized plasma is studied using three-dimensional particle-in-cell simulations. The simulations are initialized with a narrowband, relatively isotropic distribution of long wavelength whistler modes. A first ensemble of simulations at electron beta $${\beta }_{{\rm{e}}}$$ = 0.25 and ion-to-electron mass ratio $${m}_{{\rm{i}}}$$/$${m}_{{\rm{e}}}$$ = 400 is carried out on a domain cube of dimension $$L{\omega }_{\mathrm{pi}}$$/c = 5.12 where $${\omega }_{\mathrm{pi}}$$ is the ion plasma frequency. The simulations begin with a range of dimensionless fluctuating field energy densities, $${\epsilon }_{{\rm{o}}}$$, and follow the fluctuations as they cascade to broadband, anisotropic turbulence which dissipates at shorter wavelengths, heating both electrons and ions. The electron heating is stronger and preferentially parallel/antiparallel to the background magnetic field $${{\boldsymbol{B}}}_{{\rm{o}}};$$ the ion energy gain is weaker and is preferentially in directions perpendicular to $${{\boldsymbol{B}}}_{{\rm{o}}}$$. The important new results here are that, over 0.01 < $${\epsilon }_{{\rm{o}}}$$ < 0.25, the maximum rate of electron heating scales approximately as $${\epsilon }_{{\rm{o}}}$$, and the maximum rate of ion heating scales approximately as $${\epsilon }_{{\rm{o}}}^{1.5}$$. A second ensemble of simulations at $${\epsilon }_{{\rm{o}}}$$ = 0.10 and $${\beta }_{{\rm{e}}}$$ = 0.25 shows that, over 25 < $${m}_{{\rm{i}}}$$/$${m}_{{\rm{e}}}\;$$< 1836, the ratio of the maximum ion heating rate to the maximum electron heating rate scales approximately as $${m}_{{\rm{e}}}$$/$${m}_{{\rm{i}}}$$.
 [1] ;  [2] ;  [2]
  1. Space Science Institute, Boulder, CO (United States)
  2. Univ. of Southern California, Los Angeles, CA (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 1538-4357
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal
Additional Journal Information:
Journal Volume: 816; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Org:
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY turbulence; simulations; plasmas; solar wind