地球上にない二重ラムダ超原子核の同定に四半世紀ぶりに成功～歴史上2例目の快挙、核力の理解から中性子星内部の謎に迫る～

2025-12-18 理化学研究所,立教大学,岐阜大学,福井大学

ダブルラムダハイパー核（¹³_λλB）生成・崩壊に伴う飛跡がつくる3分岐点を持つ事象

＜関連情報＞

• https://www.riken.jp/press/2025/20251218_1/index.html
• https://www.nature.com/articles/s41467-025-66517-x

人工知能は二重の奇妙さの工場の先駆者となる Artificial intelligence pioneers the double-strangeness factory

Yan He,Takehiko R. Saito,Hiroyuki Ekawa,Ayumi Kasagi,Yiming Gao,Enqiang Liu,Kazuma Nakazawa,Christophe Rappold,Masato Taki,Yoshiki K. Tanaka,He Wang,Ayari Yanai,Junya Yoshida & Hongfei Zhang
Nature Communications  Published:22 November 2025
DOI:https://doi.org/10.1038/s41467-025-66517-x

Abstract

Artificial intelligence (AI) is transforming not only our daily experiences but also the technological development landscape and scientific research. In this study, we pioneered the application of AI in double-strangeness hypernuclear studies. Studies that investigate quantum systems with strangeness via hyperon interactions provide insights into fundamental baryon-baryon interactions and contribute to our understanding of the nuclear force and composition of neutron star cores. Specifically, we report the observation of a double-Λ hypernucleus in nuclear emulsion achieved via innovative integration of machine learning techniques. The proposed methodology leverages generative AI and Monte Carlo simulations to produce training datasets combined with object detection AI for effective event identification. Based on the kinematic analysis and charge identification, the observed event was uniquely identified as the production and decay of \({13\atop \Lambda \Lambda }{{\rm{B}}}\), resulting from Ξ⁻ capture by ¹⁴N in the nuclear emulsion. Assuming Ξ⁻ capture in the atomic 3D state, the binding energy of the two Λ hyperons in \({13\atop \Lambda \Lambda }{{\rm{B}}}\), B_ΛΛ, was determined as 25.57 ± 1.18(stat.) ± 0.07(syst. ) MeV. The ΛΛ interaction energy ΔB_ΛΛ obtained was 2.83 ± 1.18(stat.) ± 0.14(syst. ) MeV.