Estimation of the radiation risk to aircrew and aircraft passengers associated with atmospheric electricity events such as terrestrial gamma ray flashes and gamma ray glows

Thesis: Thunderstorms produce high-energy events discovered in the 1990’s, named terrestrial gamma ray flashes (TGFs) andgamma ray glows. TGFs are bursts of gamma rays, detectable by satellite, which last less than 100 μs. The energy ofproduced photons can reach ~40 MeV. Concerning gamma ray glows, they are increases of the background radiationlevel in thunderstorms, with longer durations (from seconds to tens of minutes) but generating photon fluxes lessimportant. Both events are produced by the same physical processes implying high-energy electrons, named relativisticrunaway electron avalanches (RREAs).Those events are produced between 10 and 15 km of altitude, being coincident with commercial flight altitudes. In thisthesis, we address the possible additional exposure due to these events for passengers and commercial aircrews. Weperformed several set of tools to answer this problematic. First, the theoretical estimation of radiation doses deliveredby TGFs using numerical simulations shows that high doses are generated by source electrons, however in compactregions. Then, a statistical study estimates the probability for an aircraft to be hit by a TGF, using satellite data and flightroutes, is weak. Finally, we present the development of a gamma ray spectrometer to detect these events in closeproximity and predictions on the future measurements that will be performed for TGFs and gamma ray glows.

Author(s)

Mélody Pallu

Date of publication
  • 2022
Keywords
  • Terrestrial gamma ray flashes TGFs
  • High energy atmospheric electrodynamic
Issuing body(s)
  • Université d’Orléans
Date of defense
  • 07/07/2022
Thesis director(s)
  • Sébastien Célestin
Version
  • 1