[P-EM08] 宇宙天気・宇宙気候

[PEM08-P08] マウンダー極小期直前における太陽活動周期の変化

*宮原 ひろ子¹、門叶 冬樹²、森谷 透²、武山 美麗²、櫻井 敬久²、堀内 一穂³、堀田 英之⁴ (1.武蔵野美術大学造形学部、2.山形大学理学部、3.弘前大学理工学部、4.千葉大学大学院理学研究院)

キーワード：太陽周期、太陽活動極小期、マウンダー極小期、炭素14

The Sun indicates long-term activity variations at the time scales of a few hundred years to a few millenia, and sometimes experience grand minima when number of sunspots significantly decreases for more than several decades. In order to understand the physical mechanism of such grand minima, we conducted high-precision measurements of carbon-14 in tree rings with annal resolution and reconstructed the solar cycles around the onset of the Maunder Minimum (1645-1715 CE). In this presentation, we report the transition of cycle lengths indicated by the high-precision data.