Precise energy calibration with position monitoring for neutrinoless double beta decay search

• Project/Area Number: 25400291
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tohoku University
• Principal Investigator: Mitsui Tadao 東北大学, ニュートリノ科学研究センター, 准教授 (20283864)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2015: ¥130,000 (Direct Cost: ¥100,000、Indirect Cost: ¥30,000); Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000)
• Keywords: ニュートリノ / 二重ベータ崩壊

Outline of Final Research Achievements

In "KamLAND-Zen" experiment, searching for neutrinoless double beta decay (0νββ)　 using Xe-136, we performed precise energy calibration with monitoring the position of the radioactive sources. The relation between light yield and energy depends on the position of the vertexes, so the uncertainty of the position of the radioactive sources contributes to the uncertainty of the energy scale. By monitoring the source position precisely then, systematic uncertainty of the energy scale has been reduced. We developed monitoring camera which can work in the oil-based liquid scintillator, to accomplish this precise position monitoring. With using the results of this precise energy calibration, we achieved the improvement in the sensitivity of search for 0νββ.

Research Products

• [Journal Article] Search for double-beta decay of 136Xe to excited states of 136Ba with the KamLAND-Zen experiment (2016)
  • Author(s): K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, M. Otani, T. Oura, I. Shimizu, Y. Shirahata, et al.
  • Journal Title: Nuclear Physics A Volume: 946 Pages: 171-181
  • DOI: 10.1016/j.nuclphysa.2015.11.011
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Results from KamLAND-Zen (2015)
  • Author(s): 清水格
  • Journal Title: AIP Conference Proceedings Volume: 1666 Pages: 170003-170003
  • DOI: 10.1063/1.4915593
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] A compact ultra-clean system for deploying radioactive sources inside the KamLAND detector (2014)
  • Author(s): T.I. Banks, S.J. Freedman, J. Wallig, N. Ybarrolaza, A. Gando, Y. Gando , H. Ikeda, K. Inoue, Y. Kishimoto, M. Koga et al.
  • Journal Title: Nucl.Instrum.Meth. Volume: A769 Pages: 8-8
  • DOI: 10.1016/j.nima.2014.09.068
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] KamLAND-Zen実験におけるγ線源を用いた位置とエネルギーの較正 (2016)
  • Author(s): 竹本康浩、他KamLAND-Zen Collaboration
  • Organizer: 日本物理学会
  • Place of Presentation: 仙台市、東北学院大学
  • Year and Date: 2016-03-19
• [Presentation] Imaging Detector for Particle Identification with Large Liquid Scintillator Detector (2014)
  • Author(s): 三井唯夫
  • Organizer: 米国電気電子学会シンポジウム (IEEE2014)
  • Place of Presentation: Washington State Convention Center (Seattle)
  • Year and Date: 2014-11-09 – 2014-11-15
• [Presentation] Imaging Detector (2014)
  • Author(s): 三井唯夫
  • Organizer: 日本地球惑星科学連合2014年大会
  • Place of Presentation: パシフィコ横浜 (横浜)
  • Year and Date: 2014-04-28 – 2014-05-02
• [Presentation] Li loaded liquid scintillator for directional measurement (2014)
  • Author(s): 白旗豊
  • Organizer: 日本地球惑星科学連合2014年大会
  • Place of Presentation: パシフィコ横浜 (横浜)
  • Year and Date: 2014-04-28 – 2014-05-02
• [Presentation] KamLAND: geo-neutrino
  • Author(s): Tadao Mitsui
  • Organizer: Workshop on Particle Geophysics
  • Place of Presentation: 東北大学
• [Presentation] KamLANDにおける位置識別性能向上に向けた開発研究
  • Author(s): 白旗豊
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 東海大学