Authors: J.H. Edyvean (School of Chemical and Physical Sciences, Victoria University of Wellington), T.N. Parashar (School of Chemical and Physical Sciences, Victoria University of Wellington), J. Juno (Princeton Plasma Physics Laboratory), T. Simpson (School of Chemical and Physical Sciences, Victoria University of Wellington), O. Koshkarov (T-5 Applied Mathematics and Plasma Physics Group, Los Alamos National Laboratory), G.L. Delzanno (T-5 Applied Mathematics and Plasma Physics Group, Los Alamos National Laboratory), V. Roytershteyn (Space Science Institute, Boulder), W.H. Matthaeus (Department of Physics and Astronomy, University of Delaware), M.A. Shay (Department of Physics and Astronomy, University of Delaware), Y. Yang (Department of Physics and Astronomy, University of Delaware ), F. Guo (Theoretical Division, Los Alamos National Laboratory), J. Goodwill (Department of Physics and Astronomy, University of Delaware)

Simulations of turbulent plasma can be performed under various approximations including fluid, hybrid kinetic, and fully kinetic approaches. The increased detail with kinetic simulations of course comes with the computational cost. A typical trick used to reduce the computational cost is to use an artificial mass ratio of the ions and electrons. A significantly larger mass is used for the electrons to reduce the bandwidth between the ion and electron scales. This reduced scale separation allows for coarser grids and hence reduced computational cost. However, the “physical” effects introduced by the artificial electron mass are not well understood. We study the effects of ion-electron mass ratio variation on the properties of turbulence at large scales, and especially at the sub-proton scales. A ten-moment two-fluid version of the Gkeyll code is used. The mass ratio is shown to have measurable effects even for some large scale properties such as the average energies. The sub-proton scale behaviour is significantly modified based on the mass ratio. Preliminary results are presented discussing the energetics, the spectral features, and plasma heating. We discuss the plans to extend this work with fully kinetic simulations.