Seed'' electrons from muon decay for runaway mechanism in the terrestrial gamma ray flash production

We describe a mechanism of enhanced terrestrial gamma ray flash production seeding via muon decay in the presence of high electric fields associated with lightning. Our model predicts 10(7) relativistic seed electrons per millisecond at about 15 km altitude with mean energy of 35 MeV and an avalanche multiplication factor of about 10(10), in good agreement with Monte Carlo simulations.