Paleari Chiara I, Mekhaldi Florian, Adolphi Florian, Christl Marcus, Vockenhuber Christof, Gautschi Philip, Beer Jürg, Brehm Nicolas, Erhardt Tobias, Synal Hans-Arno, Wacker Lukas, Wilhelms Frank, Muscheler Raimund
Department of Geology - Quaternary Sciences, Lund University, 22362, Lund, Sweden.
British Antarctic Survey, Ice Dynamics and Paleoclimate, Cambridge, CB3 0ET, UK.
Nat Commun. 2022 Jan 11;13(1):214. doi: 10.1038/s41467-021-27891-4.
During solar storms, the Sun expels large amounts of energetic particles (SEP) that can react with the Earth's atmospheric constituents and produce cosmogenic radionuclides such as C, Be and Cl. Here we present Be and Cl data measured in ice cores from Greenland and Antarctica. The data consistently show one of the largest Be and Cl production peaks detected so far, most likely produced by an extreme SEP event that hit Earth 9125 years BP (before present, i.e., before 1950 CE), i.e., 7176 BCE. Using the Cl/Be ratio, we demonstrate that this event was characterized by a very hard energy spectrum and was possibly up to two orders of magnitude larger than any SEP event during the instrumental period. Furthermore, we provide Be-based evidence that, contrary to expectations, the SEP event occurred near a solar minimum.
在太阳风暴期间，太阳会释放大量高能粒子（SEP），这些粒子可与地球大气成分发生反应并产生宇宙成因放射性核素，如碳、铍和氯。在此，我们展示了在格陵兰岛和南极洲冰芯中测量到的铍和氯数据。这些数据一致显示出迄今为止检测到的最大的铍和氯生成峰值之一，极有可能是由一次极端的SEP事件产生的，该事件在距今9125年（即公元前7176年，公元1950年之前）袭击了地球。利用氯/铍比值，我们证明该事件的特征是能谱非常硬，并且可能比仪器观测期内的任何SEP事件大两个数量级。此外，我们提供了基于铍的证据，与预期相反，该SEP事件发生在太阳活动极小期附近。
