Detection of high-energy gamma rays from winter thunderclouds

Authors: H. Tsuchiya, T. Enoto, S. Yamada, T. Yuasa, M. Kawaharada, T. Kitaguchi, M. Kokubun, H. Kato, M. Okano, S. Nakamura, K. Makishima

(Submitted on 22 Aug 2007)

Abstract: A report is made on a comprehensive observation of a burst-like $\gamma$-ray emission from thunderclouds on the Sea of Japan, during strong thunderstorms on 2007 January 6. The detected emission, lasting for $\sim$40 seconds, preceded cloud-to-ground lightning discharges. The burst spectrum, extending to 10 MeV, can be interpreted as consisting of bremsstrahlung photons originating from relativistic electrons. This ground-based observation provides first clear evidence that strong electric fields in thunderclouds can continuously accelerate electrons beyond 10 MeV prior to lightning discharges.

Comments: 12 pages, 4 figures, accepted for publication in Physical Review Letters

Subjects: Astrophysics (astro-ph); Geophysics (physics.geo-ph)

Cite as: arXiv:0708.2947v1 [astro-ph]

Submission history

From: Harufumi Tsuchiya [view email]

[v1] Wed, 22 Aug 2007 01:45:42 GMT (495kb)

http://arxiv.org/abs/0708.2947