Search for neutrinoless double beta decays with the highest sensitivities with KamLAND-Zen

2017 Fiscal Year Final Research Report

• Project/Area Number: 25220704
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tohoku University
• Principal Investigator: Shirai Junpei 東北大学, ニュートリノ科学研究センター, 教授 (90171032)
• Co-Investigator(Renkei-kenkyūsha): MITSUI Tadao 東北大学, ニュートリノ科学研究センター, 准教授 (20283864) ; SUEKANE Fumihiko 東北大学, ニュートリノ科学研究センター, 准教授 (10196678)
• Project Period (FY): 2013-05-31 – 2018-03-31
• Keywords: 素粒子（実験） / ニュートリノ / ２重ベータ崩壊

Outline of Final Research Achievements

KamLAND-Zen experiment is testing the Majorana nature of neutrinos, that is the equivalence of the particle and anti-particle, by using 136Xe nuclei. In this study a balloon holding the Xe-loaded liquid scintillator at the detector center was replaced with a much cleaner and double-volume one, and reconstruction was made on the outer part of the detector. In addition the background events were cleared and the most stringent constraint was given to the Majonara nature of neutrinos. However, leaks were found on the installed balloon and it was decided to terminate the study and restart it in a newly accepted program.

Free Research Field

素粒子・原子核・宇宙線・宇宙物理