Search for a neutral nucleus of nnLambda

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20368
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0203:Particle-, nuclear-, astro-physics, and related fields
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Itabashi Kosuke 大学共同利用機関法人高エネルギー加速器研究機構, 量子場計測システム国際拠点, 研究員 (70966499)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: nnΛ / JLab / HRS / HKS / (e,e'K+)

Outline of Final Research Achievements

The nnΛ is a neutral nucleus, and its existence has garnered significant attention.
This study aimed to understand the structure of nnΛ through the analysis of previous experimental data and to design experiments to search for the nnΛ. Through the analysis of data from the previous nnΛ search experiment, we successfully obtained the information of nΛ interaction, for which direct experimental data is unavailable. Additionally, by estimating the upper limit of the differential cross-section of nnΛ, we calculated the necessary yield to determine the existence of nnΛ and designed the setup for the next nnΛsearch experiment. Through this study, we deepened our understanding of the nnΛ structure, identified considerations necessary for confirming the existence of nnΛ, and established the foundation for planning future experiments.

Free Research Field

素粒子原子核物理実験

Academic Significance and Societal Importance of the Research Achievements

中性原子核”nnΛ”の束縛状態は理論的に説明できないにも関わらず、先行研究ではその存在を完全には否定できていない。nnΛ存否を明らかにすることは、これまでのΛハイパー核の理論モデルをより発展させる学術的意義を持つ。