AE21A-03
Positron density enhancements recorded within a thunderstorm by ADELE
Tuesday, 15 December 2015: 08:30
3001 (Moscone West)
Joseph R Dwyer1,2, David Miles Smith3, Bryna J Hazelton4, Brian Grefenstette5, Nicole Ann Kelley6, Alexander W Lowell6, Meagan Schaal7 and Hamid Rassoul8, (1)University of New Hampshire Main Campus, Department of Physics, Durham, NH, United States, (2)University of New Hampshire Main Campus, Institute for the Study of Earth, Oceans, and Space, Durham, NH, United States, (3)University of California Santa Cruz, Santa Cruz, CA, United States, (4)University of Washington, Department of Physics,, Seattle, WA, United States, (5)California Institute of Technology, Pasadena, CA, United States, (6)University of California Berkeley, Space Sciences Laboratory, Berkeley, CA, United States, (7)US Naval Research Laboratory, Monterey, CA, United States, (8)Florida Inst Tech, Melbourne, FL, United States
Abstract:
We report the observation of two unusual positron density enhancements made inside an active thunderstorm by the Airborne Detector for Energetic Lightning Emissions (ADELE) onboard a Gulfstream V aircraft in August 2009. ADELE recorded two count rate enhancements of 511 keV annihilation gamma rays, 35 seconds apart, that lasted approximately 0.2 seconds each. The enhancements were about a factor of 12 above background and had energy spectra consistent with clouds of positrons, approximately 1 km across, briefly surrounding the aircraft. A flat-plate antenna on the underside of the aircraft also recorded electrical activity during the positron enhancements. It is not clear how the positron clouds were created within the thunderstorm or whether the presence of the aircraft played a role in their production. In this presentation, we will show the ADELE data along with model fits of the positron spectra. We shall also discuss possible sources of the positron excesses.
