Lattice QCD study of diquark interactions and its applications to the excitation spectrum of Lambda_c baryon

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K03535
• 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: Ishii Noriyoshi 大阪大学, 核物理研究センター, 准教授 (40360490)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 量子色力学 / lattice QCD / チャームクォーク / ダイクォーク / チャームバリオン / 閉じ込めポテンシャル / ハドロン物理

Outline of Final Research Achievements

In order to understand the internal structure of hadrons such as protons and neutrons, an important role is expected to be played by diquarks, which consist of two quarks. However, due to the color confinement, one of the most important propergy of quantum chromodynamics (QCD), it is impossible to isolate a diquark. As a result, there exist no established ways to investigate various properties of diquarks such as mass, size, etc. both by experimental and theoretical approaches. The aim of this research is to propose and implement a method to quantitatively calculate the diquark mass using lattice QCD first-principles calculations with fully respecting
the problem of color confinement.

Free Research Field

素粒子・原子核物理理論

Academic Significance and Societal Importance of the Research Achievements

量子色力学のカラー閉じ込めに矛盾しない形で、クォーク2個からなるダイクォークの質量を始めとする様々な性質を定量的に調べる方法を定式化することは、ハドロン物理学において難問の一つである。今回の研究で行った提案は、この問題に対する一つの解答を与える。