Abstract
During the 2010 rainy season in Yangbajing (4300 m above sea level) in Tibet, China, a long-duration count enhancement associated with thunderclouds was detected by a solar-neutron telescope and neutron monitors installed at the Yangbajing Comic Ray Observatory. The event, lasting for , was observed on July 22, 2010. The solar-neutron telescope detected significant -ray signals with energies in the event. Such a prolonged high-energy event has never been observed in association with thunderclouds, clearly suggesting that electron acceleration lasts for 40 min in thunderclouds. In addition, Monte Carlo simulations showed that rays largely contribute to the neutron monitor signals, while neutrons produced via a photonuclear reaction contribute relatively less to the signals. This result suggests that enhancements of neutron monitors during thunderstorms are not necessarily clear evidence for neutron production, as previously thought.
4 More- Received 1 July 2011
DOI:https://doi.org/10.1103/PhysRevD.85.092006
© 2012 American Physical Society