Radiation dose of aircrews during a solar proton event without ground-level enhancement

Kataoka, Ryuho*; Nakagawa, Yumi*; Sato, Tatsuhiko   

A significant enhancement of radiation dose is expected for aircrews during ground-level enhancement (GLE) events, while the possible radiation hazard remains open question during on-GLE solar energetic particle (SEP) events. Using a new air shower simulation driven by the proton flux data obtained from GOES satellites, we show the possibility of significant enhancement of the effective dose rate of up to 4.5 Sv/h at conventional flight altitude of 12 km during the largest SEP event which did not cause a GLE. As a result, new GOES-driven model is proposed to give the upper limit of the radiation dose in the stratosphere during non-GLE SEP events.