| Autor: |
Terrasi, F. (F), Marzaioli, F. (F), Buompane, R. (R), Passariello, I. (I), Porzio, G. (G), Capano, M. (M), Helama, S. (S), Oinonen, M. (M), Nöjd, P. (P), Uusitalo, J. (J), Jull, A. J. (A J T), Panyushkina, I. P. (I P), Baisan, C. (C), Molnar, M. (M), Varga, T. (T), Kovaltsov, G. (G), Poluianov, S. (S), Usoskin, I. (I) |
| Jazyk: |
angličtina |
| Rok vydání: |
2020 |
| Předmět: |
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| Popis: |
Annually resolved radiocarbon (¹⁴C) measurements on tree rings led to the discovery of abrupt variations in ¹⁴C production attributed to large solar flares. We present new results of annual and subannual ¹⁴C fluctuations in tree rings from a middle-latitude sequoia (California) and a high-latitude pine (Finland), analyzed for the period 1030–1080 CE, to trace a possible impact of the Crab supernova explosion, occurring during the Oort minimum of solar activity. Our results indicate an increase of Δ¹⁴C around 1054/55 CE, which we estimate is higher in magnitude than the cyclic variability due to solar activity at a 2σ significance level. The net signal appears to be synchronized in the studied locations. Several sources of this event are possible including γ-rays from the Crab supernova, an unusually weak solar minimum or a solar energetic particle incident. More data are needed to provide more insight into the origin of this ¹⁴C event. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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