February 3, 2012, 12:00 pm - 1:00 pm

February 3, 12:00 pm - 1:00 pm

Terrestrial Gamma-Ray Flashes Produced by Energetic Electrons During Stepping of Lightning Leaders

Dr. Sebastien Celestin, Pennsylvania State University

Terrestrial gamma-ray flashes (TGFs) are high-energy photons originating from the Earth's atmosphere in association with thunderstorm activity. TGFs were serendipitously discovered by BATSE detector aboard the Compton Gamma-Ray Observatory, initially launched to perform observations of celestial sources. TGFs have also been detected and further studied by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) satellite, the Astrorivelatore Gamma a Immagini Leggero (AGILE) satellite, and the Fermi Gamma-ray Space Telescope. In addition to these space-based measurements, X-ray and gamma-ray bursts have recently been observed during natural and rocket-triggered lightning discharges. The observed X-ray and gamma-ray bursts have been linked to the production of high-energy electrons, so-called runaway electrons. The recent research efforts directed on understanding the production of high-energy photons associated with lightning will be presented.