Relativistic Runaway Electron Avalanches Within Complex Thunderstorm Electric Field Structures

Relativistic runaway electron avalanches (RREAs) are generally accepted as a source of thunderstorms gamma-ray radiation. Avalanches can multiply in the electric field via relativistic feedback mechanism based on processes with gamma-rays and positrons. This paper shows that non-uniform geometry lead to new RREAs multiplication - "reactor feedback", due exchange high-energy particles between different accelerating regions within thundercloud. A method for numerical simulation RREA dynamics heterogeneous structures is proposed. The developed analytical description enables us derive necessary conditions TGF occurrence system reactor Observable properties TGFs influenced by proposed discussed.