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arXiv · 1711.04947

A rapid cosmic-ray increase in BC 3372-3371 from ancient buried tree rings in China

F. Y. Wang·H. Yu·Y. C. Zou·Z. G. Dai·K. S. Cheng
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Abstract

Cosmic rays interact with the Earth's atmosphere to produce $^{14}$C, which can be absorbed by trees. Therefore, rapid increases of $^{14}$C in tree rings can be used to probe previous cosmic-ray events. By this method, three $^{14}$C rapidly increasing events have been found. Plausible causes of these events include large solar proton events, supernovae or short gamma-ray bursts. However, due to the lack of measurements of $^{14}$C by year, the occurrence frequency of such $^{14}$C rapidly increasing events is poorly known. In addition, rapid increases may be hidden in the IntCal13 data with five-year resolution. Here we report the result of $^{14}$C measurements using an ancient buried tree during the period between BC 3388 and 3358. We find a rapid increase of about 9\textperthousand~ in the $^{14}$C content from BC 3372 to BC 3371. We suggest that this event could originate from a large solar proton event.

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F. Y. Wang, H. Yu, Y. C. Zou, Z. G. Dai, K. S. Cheng. 2017-11-14. A rapid cosmic-ray increase in BC 3372-3371 from ancient buried tree rings in China. https://doi.org/10.1038/s41467-017-01698-8

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