Space-temporal structure of the thunderstorm ground enhancements (TGEs)

TL;DR

This study investigates the detailed space-temporal structure of Thunderstorm Ground Enhancements (TGEs) using a particle detector network, revealing that TGEs consist of multiple microbursts sustained by electron acceleration in thundercloud electric fields.

Contribution

The paper provides the first detailed statistical analysis of TGE microbursts on a nanosecond scale, supported by simulations of electron acceleration in electric fields.

Findings

TGE consists of multiple independent microbursts.

Electron acceleration sustains particle flux for minutes.

Simulations support the observed electron multiplication process.

Abstract

We analyzed the structure of the Thunderstorm Ground Enhancement using a particle detector network on Aragats. We performed a statistical analysis of the particle flux enhancement time series on a nanosecond time scale using the largest TGE event on record, which occurred on May 23, 2023. Our findings confirm that the TGE combines multiple Extensive Cloud Showers, or particle microbursts, that arrive independently and provide stable particle flux on a second time scale. The electron accelerator, operated by the dipole that emerges in the lower part of the thundercloud, sends a large number of electrons and gamma rays toward the Earths surface that sustains for minutes. The experimental results are supported by simulations of electron multiplication and acceleration in strong atmospheric electric fields.