Effect of the interplanetary magnetic field orientation and intensity in the mass and energy deposition on the Hermean surface

TL;DR

This study uses MHD simulations to analyze how different orientations and intensities of the interplanetary magnetic field affect the mass and energy deposition on Mercury's surface by interacting with its magnetosphere.

Contribution

It introduces a detailed simulation approach with multipolar magnetic field modeling to explore the impact of interplanetary magnetic field variations on Mercury's magnetospheric dynamics.

Findings

Reconnection regions correlate with plasma inflow maxima.

Magnetic field orientation influences surface energy deposition.

Magnetospheric topology varies with interplanetary magnetic field.

Abstract

The aim of the present study is to simulate the interaction between the solar wind and the Hermean magnetosphere. We use the MHD code PLUTO in spherical coordinates with an axisymmetric multipolar expansion of the Hermean magnetic field, to perform a set of simulations with different interplanetary magnetic field orientations and intensities. We fix the hydrodynamic parameters of the solar wind to study the distortions driven by the interplanetary magnetic field in the topology of the Hermean magnetosphere, leading to variations of the mass and energy deposition distributions, the integrated mass deposition, the oval aperture, the area covered by open magnetic field lines and the regions of efficient particle sputtering on the planet surface. The simulations show a correlation between the reconnection regions and the local maxima of plasma inflow and energy deposition on the planet surface.