Browsing by Subject "AD 775"

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  • Miyake, Fusa; Panyushkina, Irina; Jull, Tim; Adolphi, Florian; Brehm, N; Helama, Samuli; Kanzawa, K; Moriya, T; Muscheler, Raimund; Nicolussi, K; Oinonen, Markku; Salzer, M; Takeyama, M; Tokanai, F; Wacker, Lucas (2021)
    The annual C-14 data in tree rings is an outstanding proxy for uncovering extreme solar energetic particle (SEP) events in the past. Signatures of extreme SEP events have been reported in 774/775 CE, 992/993 CE, and similar to 660 BCE. Here, we report another rapid increase of C-14 concentration in tree rings from California, Switzerland, and Finland around 5410 BCE. These C-14 data series show a significant increase of similar to 6 parts per thousand in 5411-5410 BCE. The signature of C-14 variation is very similar to the confirmed three SEP events and points to an extreme short-term flux of cosmic ray radiation into the atmosphere. The rapid C-14 increase in 5411/5410 BCE rings occurred during a period of high solar activity and 60 years after a grand C-14 excursion during 5481-5471 BCE. The similarity of our C-14 data to previous events suggests that the origin of the 5410 BCE event is an extreme SEP event.