Research and development of external control of paired-superradiance from hydrogen gas toward the neutrino mass measurement

• Project/Area Number: 26887026
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Okayama University
• Principal Investigator: Masuda Takahiko 岡山大学, 極限量子研究コア, 助教 (90733543)
• Project Period (FY): 2014-08-29 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000); Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 二光子放出 / ニュートリノ / パラ水素 / レーザー分光 / 非線形光学

Outline of Final Research Achievements

The externally-triggered coherent two-photon emission has been observed. This phenomenon is one of essential parts of future neutrino mass measurement using atoms. In the experiment, three-color laser pulses (532, 684, 4587 nm) were simultaneously irradiated into 60-kPa para-hydrogen gas cooled down to 78K, and the pulses of 5048 nm which is two-photon emission signal were detected by photo-detectors. The resulting amplification factor against the spontaneous emission rate has been more than 10E18. Laser power dependence and trigger timing dependence were also studied, and they were able to be explained by a numerical simulation qualitatively.

Research Products

• [Journal Article] Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement (2015)
  • Author(s): Takahiko Masuda, Hideaki Hara, Yuki Miyamoto, Susumu Kuma, Itsuo Nakano, Chiaki Ohae, Noboru Sasao, Minoru Tanaka, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura
  • Journal Title: Hyperfine Interactions Volume: 236 Issue: 1-3 Pages: 73-77
  • DOI: 10.1007/s10751-015-1177-1
  • Peer Reviewed
• [Journal Article] Externally triggered coherent two-photon emission from hydrogen molecules (2015)
  • Author(s): Y. Miyamoto, H. Hara, T. Masuda, N. Sasao, M. Tanaka, S. Uetake, A. Yoshimi, K. Yoshimura, M. Yoshimura
  • Journal Title: Prog. Theor. Exp. Phys. Volume: 081C01 Issue: 8 Pages: 081C01-081C01
  • DOI: 10.1093/ptep/ptv103
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Observation of coherent two-photon emission from the first vibrationally excited state of hydrogen molecules (2014)
  • Author(s): Y. Miyamoto, H. Hara, S. Kuma, T. Masuda, I. Nakano, C. Ohae, N. Sasao, M Tanaka, S. Uetake, A. Yoshimi, K. Yoshimura and M. Yoshimura
  • Journal Title: Prog. Theor. Exp. Phys. Volume: 2014 Issue: 11 Pages: 1-12
  • DOI: 10.1093/ptep/ptu152
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] SPAN実験(ニュートリノ質量分光実験)のための対向励起実験の進行状況 (2016)
  • Author(s): 増田孝彦
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北学院大学泉キャンパス
  • Year and Date: 2016-03-19
• [Presentation] Recent progress of SPAN towards neutrino mass spectroscopy (2015)
  • Author(s): Takahiko Masuda
  • Organizer: 14th International Conference on Topics in Astroparticle and Underground Physics
  • Place of Presentation: Trin, Italy
  • Year and Date: 2015-09-07
  • Int'l Joint Research
• [Presentation] SPAN(原子を用いたニュートリノ質量分光実験)のためのマクロコヒーレンス増幅機構の詳細研究I (2015)
  • Author(s): 増田孝彦
  • Organizer: 日本物理学会 第70回年次大会
  • Place of Presentation: 早稲田大学早稲田キャンパス
  • Year and Date: 2015-03-22
• [Presentation] ニュートリノ質量分光に向けた、コヒーレンスによる二光子対超放射の観測 (2015)
  • Author(s): 増田孝彦
  • Organizer: 21st ICEPP Symposium
  • Place of Presentation: 長野県北安曇郡白馬村 岳美山荘
  • Year and Date: 2015-02-09
• [Presentation] Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement (2014)
  • Author(s): Takahiko Masuda
  • Organizer: The sixth international conference on Trapped Charged Particle and Fundamental Physics (TCP2014)
  • Place of Presentation: Kagawa International Conference Hall, Takamatsu, Kagawa, Japan
  • Year and Date: 2014-12-01