Parametric instabilities of large-amplitude parallel propagating Alfvén waves: 2D PIC simulation

Abstract

We discuss the parametric instabilities of large-amplitude parallel propagating Alfvén waves using the 2D PIC simulation code. First, we confirmed the results from a previous study (Sakai et al 2005 New J, Phys. 7 233) that the electrons are heated due to the modified two-stream instability and that the ions are heated by the parallel propagating ion acoustic waves. However, although the past study argued that such parallel propagating longitudinal waves are excited by transverse modulation of the parent Alfvén wave, we consider these waves are more likely to be generated by the usual, parallel decay instability. Further, we performed other simulation runs with different polarization of the parent Alfvén waves or different ion thermal velocity. Numerical results suggest that electron heating by the modified two-stream instability due to the large amplitude Alfvén waves is unimportant with most parameter sets. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.