Faculty of Mathematics, Physics
and Informatics
Comenius University Bratislava

Special Nuclear Seminar - prof. A.J.T. Jull (1.12.2025)

Monday 1.12.2025 at 14:00, Lecture rook F1/364


26. 11. 2025 16.17 hod.
By: Jaroslav Staníček

prof. A.J.T. Jull (University of Arizona, Tucson, USA and visiting professor at the Institute for Nuclear Sciences of the Hungarian Academy of Sciences, Debrecen, Hungary):
Radiocarbon in tree rings - recent discoveries of past large solar flares

Abstract:
Extreme solar energetic particle events, known as Miyake events, are rare phenomena observed in short radiocarbon variations in tree rings during the BCE. We shall present results of recent measurements in an arctic tree (664–663 BCE). Using a box carbon cycle model and Bayesian statistics, we calculated the radiocarbon production rate during the event that is 3.2–4.8 times higher than the average solar modulation, and comparable to the 774–775 CE Miyake solar-proton event. We caution about using the event’s pronounced signature for precise single- year-dating.