High energetic radiation from thunderstorms and lightning

Abstract

Electrical discharges in gases can be roughly divided into two categories: those whose behavior is governed by low-energy electrons, with energies less than a few tens of eV, and those whose behavior is governed by high-energy electrons, with energies often reaching several tens of MeV. The first category, which we shall refer to as low-energy discharges, is also called conventional discharges, which includes a wide range of phenomena such as corona discharges, including streamer and glow discharges, Trichel pulses, Townsend discharges, and spark breakdown [Loeb, 1965]. In this chapter, we first review the observations of high-energy atmospheric physics processes within our atmosphere, including x-ray emissions from lightning and gamma-ray emissions, such as gamma-ray glows and TGFs, from thunderclouds. We then introduce and explain the mechanisms involved in high-energy discharges and compare these mechanisms to their low-energy counterparts. We also discuss recent models that have been developed to explain TGFs, including “dark lightning.”