We present ground‐based measurements of thunderstorm‐related enhancements of fluxes of energetic radiation and particles that are abruptly terminated by lightning discharges. All measurements were performed at an altitude of 3200 m above sea level on Mount Aragats (Armenia). Lightning signatures were recorded using a wideband electric field measuring system with a useful frequency bandwidth of 50 Hz to 12 MHz and network of five electric field mills, three of which were installed at the Aragats station, one at the Nor Amberd station (12.8 km from Aragats), and one at the Yerevan station (39 km from Aragats). We observed that the flux‐enhancement termination was associated only with close (within 10 km or so of the particle detector) negative CGs and normal‐polarity ICs; that is, with lightning types which reduce the upward directed electric field below the cloud and hence suppress the acceleration of electrons toward the ground.
The relationship of lightning and elementary particle fluxes in the thunderclouds is not fully understood to date. Using the particle beams (the so-called Thunderstorm Ground Enhancements – TGEs) as a probe we investigate the characteristics of the interrelated atmospheric processes. The well-known effect of the TGE dynamics is the abrupt termination of the particle flux by the lightning flash. With new precise electronics, we can see that particle flux decline occurred simultaneously with the rearranging of the charge centers in the cloud. The analysis of the TGE energy spectra before and after the lightning demonstrates that the high-energy part of the TGE energy spectra disappeared just after lightning. The decline of particle flux coincides on millisecond time scale with first atmospheric discharges and we can conclude that Relativistic Runaway Electron Avalanches (RREA) in the thundercloud assist initiation of the negative cloud to ground lightning. Thus, RREA can provide enough ionization to play a significant role in the unleashing of the lightning flash.
Proceeding from the measurements of the lightning occurrences, slow and fast electricfield disturbances, particle flux enhancements and their abrupt terminations, we formulate a lightning origination model. Registration of the extensive air shower simultaneously with lightning detection allows us to propose a solution to the long-standing problem of its role in the lightning initiation. Our analysis is based on the numerous Thunderstorm Ground Enhancements detected in 2012-2014 at Mt. Aragats in Armenia.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.