Measurements of meson mass modification in nuclei due to the partial restoration of chiral symmetry

2016 Fiscal Year Final Research Report

• Project/Area Number: 26247048
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Yokkaichi Satoshi 国立研究開発法人理化学研究所, 仁科加速器研究センター, 専任研究員 (20360670)
• Co-Investigator(Renkei-kenkyūsha): TAKAHASHI Tomonori 国立研究開発法人理化学研究所, 仁科加速器研究センター, 客員研究員 (80612134) ; 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, 助教 (70525328) ; MORINO Yuhei 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, 助教 (50715240)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 実験核物理 / 放射線X線粒子線 / GEM / チェレンコフ検出器 / 電子検出器 / 飛跡検出器 / カイラル対称性 / 量子色力学

Outline of Final Research Achievements

The origin of hadron mass is thought to be due to the spontaneous breaking of chiral symmetry, not only the Higgs mechanism, as Nambu advocated. In order to obtain the experimental evidence of the idea, we proposed the systematic measurement of vector meson mass in nuclei with the world best resolution and statistics through the di-electron decay at J-PARC hadron experimental facility. In order to construct a spectrometer for the experiment, we have developed the GEM tracker, Hadron blind detector and read-out electronics, and produced a part of them which consist the spectrometer. Also, by the simulation based on the achieved performance of the developed detectors, we evaluated the sensitivity to the spectral modification of the phi meson using the limited number of the detectors, only eight modules out of 26 modules originally proposed.

Free Research Field

原子核物理学