MAGNETIC HELICITY OF ION KINETIC TURBULENCE WITH A NONZERO ELECTRON TEMPERATURE

Hybrid numerical simulations of strong turbulence with a nonzero electron temperature are carried out in the proton kinetic range. The turbulent cascade is initiated by a large-scale spectrum with a nonzero cross-helicity. The turbulence evolves freely and produces a magnetic helicity spectrum with a peak at smaller scales. Testing is performed to verify that the shape of the peak is not affected by numerical artifacts. The magnetic helicity spectrum is shown to be determined by both the electron and proton thermal pressures, rather than the proton pressure alone. Implications for the observed correlations between the magnetic helicity and the plasma parameters in the solar wind are discussed.