Experimental Study of Neutrino CP Violation by using an Accelerator Neutrino Beam

2016 Fiscal Year Final Research Report

• Project/Area Number: 24244030
• 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: Kyoto University
• Principal Investigator: Tsuyoshi Nakaya 京都大学, 理学研究科, 教授 (50314175)
• Co-Investigator(Kenkyū-buntansha): 横山 将志 東京大学, 理学(系)研究科(研究院), 准教授 (90362441)
• Co-Investigator(Renkei-kenkyūsha): ICHIKAWA Atsuko 京都大学, 大学院理学研究科, 教授 (50353371) ; MINAMINO Akihiro 横浜国立大学, 理学研究科, 准教授 (70511674) ; SHIOZAWA Masato 東京大学, 宇宙線研究所, 教授 (70272523)
• Project Period (FY): 2012-04-01 – 2017-03-31
• Keywords: 素粒子 / ニュートリノ / 加速器 / ビーム / CP対称性

Outline of Final Research Achievements

We conducted research on neutrino oscillation, measurements by using an anti-neutrino beam, and development of high performance photon-sensor for a next generation large-scale neutrino experiment. In the T2K experiment, we observed the signal from the muon neutrino to the electron neutrino and found the appearance of the electron neutrino with significance of 7.3 σ. We measured the oscillation probability to the electron neutrino and constrained the neutrino CP violation parameter for the first time in the world　(δCP = - 0.5 π was the best). An anti-neutrino beam was generated, and the parameters of anti-neutrino oscillation were measured with the highest precision.
We studied the sensitivity of neutrino CP violation with the next-generation experiment, Hyper Kamiokande. We also succeeded in developing a high performance photon-sensor (joint work with Hamamatsu Photonics).

Free Research Field

素粒子物理学