Ultrahigh sensitivity neutrino-less double beta decay search with a new type of detector with direction information added

• Project/Area Number: 17H04834
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Tohoku University
• Principal Investigator: Ueshima Kota 東北大学, ニュートリノ科学研究センター, 助教 (80605379)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥25,090,000 (Direct Cost: ¥19,300,000、Indirect Cost: ¥5,790,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥11,310,000 (Direct Cost: ¥8,700,000、Indirect Cost: ¥2,610,000); Fiscal Year 2017: ¥12,220,000 (Direct Cost: ¥9,400,000、Indirect Cost: ¥2,820,000)
• Keywords: 波長変換剤 / 二重ベータ崩壊 / 液体キセノン / 方向検出 / 波長変換材 / ニュートリノ

Outline of Final Research Achievements

The R&D for a new type of liquid xenon (LXe) detector is ongoing to search for the neutrinoless double-beta decay (0ν2β). The detector concept is LXe stored in a new type of plastic scintillator vessel. The wavelength of LXe scintillation light was shifted to visible light from 175nm (VUV) on the inner surface of the vessel. It was found that the pulse shape difference between LXe and plastic scintillator was useful for BG reduction.

Academic Significance and Societal Importance of the Research Achievements

新しい液体キセノン検出器を開発した。液体キセノンのシンチレーション光をプラシン容器内面で波長変換することで、液体キセノンの発光波形は、波形の立ち上がり成分が緩やかになり、立ち上がりの早いチェレンコフ光と区別して検出しやすくなる。液体キセノンの発光波形に埋もれた、チェレンコフ光成分を抽出することにより、液体キセノン検出器に方向の情報を付加でき、将来究極のBGとなる8B太陽ニュートリノ低減に向けた研究開発を行なった。

Research Products

• [Journal Article] Liquid Xenon detector R&D for 0ν2β search (KamXP) (2020)
  • Author(s): Kota Ueshima
  • Journal Title: Journal of Physics: Conference Series Volume: 1468 Issue: 1 Pages: 012138-012138
  • DOI: 10.1088/1742-6596/1468/1/012138
  • Peer Reviewed / Open Access
• [Presentation] Neutrinoless Double Beta Decay Status and Prospects (2020)
  • Author(s): Kota Ueshima
  • Organizer: 3rd World Summit on Exploring the Dark Side of Universe (remote talk)
  • Int'l Joint Research / Invited
• [Presentation] Experimental status of neutrinoless double beta decay searches (2019)
  • Author(s): Kota Ueshima
  • Organizer: 3 neutrinos and beyond
  • Int'l Joint Research / Invited
• [Presentation] Liquid Xenon detector R&D for 0v2b search (KamXP) (2019)
  • Author(s): Kota Ueshima
  • Organizer: Topics in Astroparticle and Underground Physics (TAUP2019)
  • Int'l Joint Research
• [Presentation] 0v2b探索に向けた液体キセノン検出器の研究開発 (2019)
  • Author(s): 上島考太
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] Liquid Xenon detector R&D for 0v2b search (poster) (2019)
  • Author(s): Kota Ueshima
  • Organizer: Revealing the history of the universe with underground particle and nuclear research 2019
  • Int'l Joint Research
• [Presentation] 0v2b探索に向けた液体キセノン検出器開発 (poster) (2019)
  • Author(s): 上島考太
  • Organizer: 第5回極低放射能技術研究会
• [Presentation] KamLAND-Zen Results and purification methods (2017)
  • Author(s): Kota Ueshima
  • Organizer: XeSAT2017
  • Int'l Joint Research / Invited
• [Presentation] 高圧液体キセノンを用いた0ν2β探索の基礎研究 (2017)
  • Author(s): 上島 考太
  • Organizer: 新学術地下素核研究 2017領域研究会
  • Invited
• [Presentation] 高圧キセノンシンチレータ (2017)
  • Author(s): 上島 考太
  • Organizer: 2017年度CRC将来計画タウンミーティング
  • Invited