Thunder-cell as Source of Energetic Protons

TL;DR

This paper hypothesizes that thunder-clouds emit energetic protons which create tree-like ionization paths, potentially explaining lightning channels, with geometric and reaction considerations supporting the idea.

Contribution

It introduces a novel hypothesis linking energetic protons from thunder-clouds to lightning channel formation, incorporating geometric and nuclear reaction analyses.

Findings

Mean free path of protons is about 660 m in lower Earth atmosphere.

Predicted CG/CC ratio aligns with observed data.

Lightning geometry measurements are needed to validate the hypothesis.

Abstract

In this article we present the following hypothesis: thunder-cell ejects highly energetic protons, each of which creates a tree-structure of weakly ionized trajectories that can develop into a lightning channel. The tree-structure and the channel have the same geometry so the mean free path of a proton corresponds to the average length of the channel between two successive nodes (branching points). We show this length is around 660 m in lower Earth atmosphere. Effects of Coulomb interaction and various outcomes of proton-nucleus reaction are taken into account. A prediction of CG/CC ratio that follows agrees well with the available data, but only measurements of lightning geometry can reveal whether the hypothesis is any closer to the correct explanation of the phenomenon.