title: TETRA observation of gamma-rays at ground level associated with nearby thunderstorms.
abstract: [1] Terrestrial gamma-ray flashes (TGFs)-very short, intense bursts of electrons, positrons, and energetic photons originating from terrestrial thunderstorms-have been detected with satellite instruments. TGF and Energetic Thunderstorm Rooftop Array (TETRA), an array of NaI(Tl) scintillators at Louisiana State University, has now been used to detect similar bursts of 50 keV to over 2 MeV gamma-rays at ground level. After 2.6 years of observation, 24 events with durations 0.02-4.2 ms have been detected associated with nearby lightning, three of them coincident events observed by detectors separated by ∼1000 m. Nine of the events occurred within 6 ms and 5 km of negative polarity cloud-to-ground lightning strokes with measured currents in excess of 20 kA. The events reported here constitute the first catalog of TGFs observed at ground level in close proximity to the acceleration site.
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Ringuette
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA ; Now at Department of Physics, La Sierra University Riverside, California, USA.
authors.forename: Gary L
authors.initials: GL
authors.lastname: Case
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Cherry
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: Douglas
authors.initials: D
authors.lastname: Granger
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: T Gregory
authors.initials: TG
authors.lastname: Guzik
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Stewart
authors.affiliation: Department of Physics and Astronomy, Louisiana State University Baton Rouge, Louisiana, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Wefel
keywords: terrestrial gamma flashes