Despite being one of the most familiar and widely recognized natural phenomena, lightning
remains relatively poorly understood. Even the most basic questions of how lightning is …

It is now well established that both thunderclouds and lightning routinely emit x-rays and
gamma-rays. These emissions appear over wide timescales, ranging from sub-microsecond …

The present white paper is submitted as part of the “Snowmass” process to help inform the
long-term plans of the United States Department of Energy and the National Science …

The Aragats Space Environmental Center facilities continuously measure fluxes of neutral
and charged secondary cosmic ray incidents on the Earth's surface. Since 2003 in the 1 …

The Gamma‐ray Burst Monitor (GBM) on the Fermi Gamma‐ray Space Telescope detected
12 intense terrestrial gamma ray flashes (TGFs) during its first year of observation. Typical …

As thunderclouds charge, the large‐scale fields may approach the relativistic feedback
threshold, above which the production of relativistic runaway electron avalanches becomes …

The source of terrestrial gamma‐ray flashes (TGFs) has remained a mystery since their
discovery in 1994. Recent Reuven Ramaty High‐Energy Solar Spectroscopic Imager …

The energy spectra of Thunderstorm ground enhancement (TGE) electrons and gamma rays
are the key evidence for proving the origin of enhanced particle fluxes from thunderclouds …

Two types of high-energy events have been detected from thunderstorms. One is “terrestrial
gamma-ray flashes”(TGFs), sub-millisecond emissions coinciding with lightning discharges …

We present a detailed investigation of X‐ray emission from long laboratory sparks in air at
atmospheric pressure. We studied 231 sparks of both polarities using a 1‐MV Marx …