Mapping Observation Project of High-Energy Phenomena during Winter Thunderstorms in Japan
Abstract
The Gamma-Ray Observation of Winter Thunderclouds (GROWTH) collaboration has been performing observation campaigns of high-energy radiation in coastal areas of Japan Sea. Winter thunderstorms in Japan have unique characteristics such as frequent positive-polarity discharges, large discharge current, and low cloud bases. These features allow us to observe both long-duration gamma-ray bursts and lightning-triggered short-duration bursts at sea level. In 2015, we started a mapping observation project using multiple detectors at several new observation sites. We have developed brand-new portable gamma-ray detectors and deployed in the Kanazawa and Komatsu areas as well as the existing site at Kashiwazaki. During three winter seasons from 2015, we have detected 27 long-duration bursts and 8 short-duration bursts. The improved observation network in Kashiwazaki enables us to discover that the short-duration bursts are attributed to atmospheric photonuclear reactions triggered by a downward terrestrial gamma-ray flash. Collaborating with electric-field and radio-band measurements, we have also revealed a relation between abrupt termination of a long-duration burst and a lightning discharge. We demonstrate that the mapping observation project has been providing us clues to understand high-energy atmospheric phenomena associated with thunderstorm activities.
Keywords
Cite
@article{arxiv.1811.06212,
title = {Mapping Observation Project of High-Energy Phenomena during Winter Thunderstorms in Japan},
author = {Yuuki Wada and Teruaki Enoto and Yoshihiro Furuta and Kazuhiro Nakazawa and Takayuki Yuasa and Takahiro Matsumoto and Daigo Umemoto and Kazuo makishima and Harufumi Tsuchiya and the GROWTH collaboration},
journal= {arXiv preprint arXiv:1811.06212},
year = {2018}
}
Comments
10 pages, 9 figures, to appear in TEPA (Thunderstorms and Elementary Particle Acceleration) 2018 conference proceedings