Study of multistrange baryons via three-body decays of charmed baryons

Research Project

Project/Area Number	18K03632
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
Research Institution	Osaka University
Principal Investigator	Kamano Hiroyuki 大阪大学, 核物理研究センター, 技術専門職員 (00625361)
Project Period (FY)	2018-04-01 – 2021-03-31
Project Status	Completed (Fiscal Year 2020)
Budget Amount *help	¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000) Fiscal Year 2020: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords	ハドロン分光 / マルチストレンジバリオン / 部分波解析 / 三体崩壊
Outline of Final Research Achievements	Non-leptonic three-body weak decays of charmed baryons have been considered to provide vital information for establishing the mass spectrum of mysterious multistrange baryons. Because of this, various theoretical approaches have been applied to analyze the data for such decays and explore the multistrange baryons. However, so far the so-called three-body final-state interactions (FSIs) in the decay processes have been neglected in the theoretical analyses because the inclusion of such interactions requires highly complicated numerical treatments. In this study, we have developed a new microscopic model for the three-body decays of charmed baryons, in which the three-body FSIs are fully taken into account. With this new model, we have shown that the three-body FSIs can significantly affect the shape and magnitude of the decay quantities, indicating that incorporation of the three-body FSIs is crucial for a reliable extraction of the multistrange baryon properties from the decay data.
Academic Significance and Societal Importance of the Research Achievements	本研究で示されたチャームバリオンの非レプトン三体弱崩壊過程における三体終状態相互作用の重要性は、三体終状態相互作用の効果を無視する従来の実験データの解析手法では、崩壊後の二体部分系として現れるマルチストレンジバリオンの情報を正しく抽出することができない可能性を強く示唆する。本研究で開発した微視的反応模型をさらに発展させ、当該模型をベースにした信頼性の高い理論解析を通じてマルチストレンジバリオンの質量スペクトルを確立することにより、クォークからハドロンが生成される初期宇宙の歴史の解明への貢献が期待できる。