Systematic study of restoration of broken chiral symmetry

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01102
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Aoki Kazuya 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 研究機関講師 (70525328)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: カイラル対称性の自発的破れ

Outline of Final Research Achievements

We proposed J-PARC E16 experiment to study the origin of hadron mass. For that purpose we need Silicon Tracking System (STS) and GEM tracker (GTR). In this study we have developed STS with the CBM experiment team at GSI, Germany. We have prepared a prototype STS and evaluated its performance and learned about its characteristics and operations using electron beam. We have designed and built STS chamber and installed the silicon sensor into the chamber. We have evaluated the performance of the STS chamber and confirmed that the performance satisfied our needs. We have installed the chamber into the experimental area. We have also built and installed GTRs. We have performed commission run using proton beams with the highest design intensity. We are analyzing the data.

Free Research Field

素粒子原子核物理学実験

Academic Significance and Societal Importance of the Research Achievements

ハドロン質量の起源としてのカイラル対称性の自発的破れは、ハドロン物理の基本的な問題であり実験的検証がなされることは学術的意義が大きい。本研究費によって最内層シリコン検出器が完成してインストールでき、設計の最高機輝度ビーム下での動作確認ができた。また、その周囲を囲むGEM飛跡検出器についてもアクセプタンス増強を行うことができた。この実験の物理実験の採択を得るためには検出器の性能を示す必要があり、その為のデータを取得できことは、大きな一歩である。今後解析を行って検出器の性能を示し、物理実験の採択を得る。