Gyrokinetic Simulations of Solar Wind Turbulence from Ion to Electron Scales

G. G. Howes, J. M. TenBarge, W. Dorland, E. Quataert, A. A. Schekochihin, R. Numata, and T. Tatsuno

Phys. Rev. Lett. 107, 035004 – Published 14 July 2011

Abstract

A three-dimensional, nonlinear gyrokinetic simulation of plasma turbulence resolving scales from the ion to electron gyroradius with a realistic mass ratio is presented, where all damping is provided by resolved physical mechanisms. The resulting energy spectra are quantitatively consistent with a magnetic power spectrum scaling of $k^{- 2.8}$ as observed in in situ spacecraft measurements of the “dissipation range” of solar wind turbulence. Despite the strongly nonlinear nature of the turbulence, the linear kinetic Alfvén wave mode quantitatively describes the polarization of the turbulent fluctuations. The collisional ion heating is measured at subion-Larmor radius scales, which provides evidence of the ion entropy cascade in an electromagnetic turbulence simulation.

Received 21 March 2011

DOI:https://doi.org/10.1103/PhysRevLett.107.035004

Authors & Affiliations

G. G. Howes^1,2,*, J. M. TenBarge¹, W. Dorland^3,2, E. Quataert⁴, A. A. Schekochihin^5,2, R. Numata^3,2, and T. Tatsuno³

¹Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242, USA
²Isaac Newton Institute for Mathematical Sciences, Cambridge, CB3 0EH, United Kingdom
³Department of Physics, University of Maryland, College Park, Maryland 20742-3511, USA
⁴Department of Astronomy, University of California, Berkeley, California 94720, USA
⁵Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, OX1 3NP, United Kingdom