Title: Proton-induced halo formation in charged meteors,
Abstract: Despite a very long history of meteor science, our understanding of meteor
ablation and its shocked plasma physics is still far from satisfactory as we
are still missing the microphysics of meteor shock formation and its plasma
dynamics. Here we argue that electrons and ions in the meteor plasma above
$\sim$100 km altitude undergo spatial separation due to electrons being trapped
by gyration in the Earth's magnetic field, while the ions are carried by the
meteor as their dynamics is dictated by collisions. This separation process
charges the meteor and creates a strong local electric field. We show how
acceleration of protons in this field leads to the collisional excitation of
ionospheric N$_2$ on the scale of many 100 m. This mechanism explains the
puzzling large halo detected around Leonid meteors, while it also fits into the
theoretical expectations of several other unexplained meteor related phenomena.
We expect our work to lead to more advanced models of meteor-ionosphere
interaction, combined with the electrodynamics of meteor trail evolution.