# Colliding Alfv\'enic wave packets in MHD, Hall and kinetic simulations

## TL;DR

This paper investigates the collision of Alfvénic wave packets using MHD, Hall, and kinetic simulations, revealing dispersive and kinetic effects, non-Maxwellian features, and solar wind-like proton distributions.

## Contribution

It extends the Parker-Moffatt problem analysis by incorporating Hall and kinetic models, providing detailed insights into dispersive and kinetic phenomena during wave packet collisions.

## Key findings

- Regions with strong temperature anisotropy form during collisions
- Proton distribution functions develop beams along magnetic field lines
- Dispersive and kinetic effects are significant in wave interactions

## Abstract

The analysis of the Parker-Moffatt problem, recently revisited in Pezzi et al. (2016), is here extended by including the Hall magnetohydrodynamics and two hybrid kinetic Vlasov-Maxwell numerical models. The presence of dispersive and kinetic features is studied in detail and a comparison between the two kinetic codes is also reported. Focus on the presence of non-Maxwellian signatures shows that - during the collision - regions characterized by strong temperature anisotropy are recovered and the proton distribution function displays a beam along the direction of the magnetic field, similar to some recent observations of the solar wind.