The neutrino oscillation analysis with tau neutrino appearance in a long-baseline accelerator experiment

2016 Fiscal Year Final Research Report

• Project/Area Number: 25707019
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University (2016); Toho University (2013-2015)
• Principal Investigator: FUKUDA Tsutomu 名古屋大学, 高等研究院(理学研究科), YLC特任助教 (10444390)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: ニュートリノ振動 / 原子核乾板 / タウニュートリノ / OPERA実験 / CERN / Appearance / J-PARC / NINJA実験

Outline of Final Research Achievements

Total five tau neutrino events have been detected, allowing to reject the background-only hypothesis at 5.1 sigma through this research. This means that tau neutrino appearance has been discovered and the biggest goal of the OPERA experiment has been successfully achieved. Consequently, final verification for the neutrino oscillation has been completed. Then the accuracy for neutrino oscillation measurement in OPERA has been improved with new (looser) selection criteria for tau neutrino detection and reduction of the systematic error by a detailed study for the background. Furthermore, I proposed a new experimental project that aims at precise measurement of neutrino interactions with nuclear emulsion detector at J-PARC for next generation neutrino oscillation experiments. The NINJA Collaboration was newly established for this purpose with myself being a Principal Investigator (PI). We have implemented the neutrino beam exposure with water and iron target emulsion detector at J-PARC.

Free Research Field

素粒子・原子核・宇宙線・宇宙物理