understanding of particle acceleration in lightning and thunderclouds via measurement of x rays and nuclear-gamma rays

观测到了可能与雷暴活动中电子加速有关的高能伽马射线。考虑到这些观测，我们得到了一个新的想法，即这种伽马射线揭示了电场加速的机制，这是很难通过空间测量来研究的。因此，自2006年以来，一直在日本海的沿海地区和高山进行伽马射线观测。到2010年2月，共获得8次雷云伽马射线事件。这些探测证实了雷雨云确实是天然的粒子加速器。

High-energy gamma rays, which are possibly associated with electron acceleration in thunderstorm activity, have been observed. Given these observations, we obtained a new idea that such gamma rays reveal mechanisms of electric-field acceleration, which is difficult to be investigated by space measurement. Hence, gamma-ray observations have been performed since 2006, at the coastal area of Japan sea and at a high mountain. By 2010 February, 8 thundercloud gamma-ray events were obtained. These detections confirmed that thunderclouds are indeed natural particle accelerators.