ニュートリノ質量起源としての新型ヒッグス模型の宇宙論的研究

• Project Area: Unification and Development of the Neutrino Science Frontier
• Project/Area Number: 26105514
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Hokkai-Gakuen University
• Principal Investigator: 瀬戸 治 北海学園大学, 工学部, 准教授 (40547741)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000); Fiscal Year 2015: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: ニュートリノフィリックヒッグス場 / ニュートリノフィリックヒッグス模型

Outline of Annual Research Achievements

本研究計画の目的は、複数のヒッグ場を持つ素粒子模型の一種でニュートリノの質量の起源の生成のみを担うヒッグス場（ニュートリノフィリックヒッグス模型）の宇宙論・宇宙物理的の側面を研究し、ニュートリノ質量起源としてのニュートリノフィリックヒッグス模型の性質や構造、実験・観測的制限を明らかにすることです。
前年度は申請時の予定を上回るペースで結果を出すことが出来、申請当時の計画課題としては、不活性ニュートリノ暗黒物質の解析、のみを残す状態となっていました。この研究を始めるため、ニュートリノフィリックヒッグス場とニュートリノの結合について検討した際に、この結合を通じて125ギガ電子ボルトの質量を持つ標準模型的なヒッグス粒子が、非標準的な崩壊パターンで崩壊し得ることに気がついた。2015年からLHC実験のセカンドランが始まっておりヒッグス粒子に関するデータも蓄積されることが予想されたので、計画を変更し、このヒッグス粒子の非標準的な崩壊モードに関する研究を優先させることとした。その非標準的崩壊モードとはニュートリノへ崩壊することによるヒッグス粒子の不可視崩壊で、他のヒッグス粒子の質量スペクトル次第では非常に大きくなることを見いだし、論文として発表した。この優先順位変更のため当初解析予定であった不活性ニュートリノ暗黒物質の計画は実行できなかったが、不活性ニュートリノやアクシオン的粒子の検出を主目的としてセルンで検討中の将来のビームダンプ実験である ShiP 実験に関する物理研究論文に寄稿した為、その代替研究として十分な貢献ができた。当該論文は Reports on Progress in Physics 誌に受理され現在印刷中。

Research Progress Status

27年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

27年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] アラバマ大学/ノースウエスタン大学/マサチューセッツ工科大学(米国)
• [Int'l Joint Research] セルン(スイス)
• [Int'l Joint Research] DESY/ハイデルベルグ大学(ドイツ)
• [Int'l Joint Research] ビクトリア大学(カナダ)
• [Int'l Joint Research] グルノーブル大学/リヨン大学(フランス)
• [Int'l Joint Research]
• [Int'l Joint Research] アラバマ大学/ラトガース大学(米国)
• [Int'l Joint Research] KASI(韓国)
• [Journal Article] A facility to Search for Hidden Particles at the CERN SPS: the SHiP physics case (2016)
  • Author(s): Sergey Alekhin et al.
  • Journal Title: Reports on Progress in Physics Volume: 79
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Entropy production by domain wall decay in the NMSSM (2015)
  • Author(s): H. Hattori, T. Kobayashi, N. Omoto and O. Seto,
  • Journal Title: Physical Review D Volume: 92 Issue: 10 Pages: 1-9
  • DOI: 10.1103/physrevd.92.103518
  • NAID: 120005690889
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Large invisible decay of a Higgs boson to neutrinos (2015)
  • Author(s): Osamu Seto
  • Journal Title: Physicsl Review D Volume: 92 Issue: 7 Pages: 073005-073005
  • DOI: 10.1103/physrevd.92.073005
  • Acknowledgement Compliant
• [Journal Article] Dilution of axion dark radiation by thermal inflation (2015)
  • Author(s): H. Hattori, T. Kobayashi, N. Omoto and O. Seto
  • Journal Title: Phys. Rev. Volume: D92 Issue: 2 Pages: 1-6
  • DOI: 10.1103/physrevd.92.023517
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Beginning of Universe through large field hybrid inflation (2015)
  • Author(s): Tatsuo Kobayashi, Osamu Seto
  • Journal Title: Modern Physics Letters A Volume: 31 Issue: 21 Pages: 1550106-1550106
  • DOI: 10.1142/s0217732315501060
  • NAID: 120005773969
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Phenomenology in supersymmetric neutrinophilic Higgs model with sneutrino dark matter (2014)
  • Author(s): Ki-Young Choi, Osamu Seto, Chang Sub Shin
  • Journal Title: Journal of High Energy Physics Volume: 09(2014) Issue: 9 Pages: 068-068
  • DOI: 10.1007/jhep09(2014)068
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Axion monodromy inflation with multi-natural modulations (2014)
  • Author(s): Tetsutaro Higaki, Tatsuo Kobayashi, Osamu Seto, Yuya Yamaguchi
  • Journal Title: Journal of Cosmology and Astroparticle Physics Volume: 10 Issue: 10 Pages: 025-025
  • DOI: 10.1088/1475-7516/2014/10/025
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Axion monodromy inflation with sinusoidal corrections (2014)
  • Author(s): Tatsuo Kobayashi, Osamu Seto, Yuya Yamaguchi
  • Journal Title: Progress of Theoretical Experimental Physics Volume: 103E01 Issue: 10 Pages: 103E01-103E01
  • DOI: 10.1093/ptep/ptu145
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Galactic Center gamma-ray excess from two Higgs doublet portal dark matter (2014)
  • Author(s): Nobuchika Okada, Osamu Seto
  • Journal Title: Physical Review D Volume: 90 Issue: 8 Pages: 083523-083523
  • DOI: 10.1103/physrevd.90.083523
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] Singlet doublet mixed complex scalar dark matter (2016)
  • Author(s): Osamu Seto
  • Organizer: 12th UCLA dark matter symposium
  • Place of Presentation: UCLA、アメリカ
  • Year and Date: 2016-02-17
  • Int'l Joint Research
• [Presentation] New invisible decay modes of the SM-like Higgs boson (2015)
  • Author(s): Osamu Seto
  • Organizer: 26th Busan Workshop on particle physics, string theory and cosmology
  • Place of Presentation: 釜山、韓国
  • Year and Date: 2015-12-02
  • Int'l Joint Research / Invited
• [Presentation] New invisible decay modes of the SM-like Higgs boson (2015)
  • Author(s): Osamu Seto
  • Organizer: Particle Cosmology and beyond 2015
  • Place of Presentation: 金沢、石川
  • Year and Date: 2015-11-16
  • Int'l Joint Research
• [Presentation] Galactic Center excess by two Higgs doublet portal scalar dark matter (2015)
  • Author(s): Osamu Seto
  • Organizer: TeV Particle Astrophysics 2015
  • Place of Presentation: 柏、千葉
  • Year and Date: 2015-10-26
  • Int'l Joint Research
• [Presentation] Galactic Center excess by Higgs portal dark matter (2015)
  • Author(s): Osamu Seto
  • Organizer: 12th Conference in the Symposium on Cosmology and Particle Astrophysics
  • Place of Presentation: 大田、韓国
  • Year and Date: 2015-10-12
  • Int'l Joint Research
• [Presentation] Galactic Center excess by Higgs portal dark matter (2015)
  • Author(s): Osamu Seto
  • Organizer: XIV International Conference on Topics in Astroparticle and Underground Physics
  • Place of Presentation: トリノ、イタリア
  • Year and Date: 2015-09-07
  • Int'l Joint Research
• [Presentation] Dulition of axion dark radiation (2015)
  • Author(s): Osamu Seto
  • Organizer: The 2015 Europhysics Conference on High Energy Physics-HEP 2015
  • Place of Presentation: ウィーン、オーストリア
  • Year and Date: 2015-07-22
  • Int'l Joint Research
• [Presentation] 宇宙論屋から見たILC (2015)
  • Author(s): Osamu Seto
  • Organizer: ILC 夏の合宿 2015
  • Place of Presentation: 伊香保温泉、群馬
  • Year and Date: 2015-07-18
  • Invited
• [Presentation] Invisible decay of a Higgs boson and dark matter (2015)
  • Author(s): Osamu Seto
  • Organizer: CosKASI Dark Matter Workshop 2015
  • Place of Presentation: 大田、韓国
  • Year and Date: 2015-06-09
  • Int'l Joint Research / Invited
• [Presentation] ILC prospect for testing Higgs portal WIMP motivated by Galactic Center excess (2015)
  • Author(s): Osamu Seto
  • Organizer: Asian Linear Collider Workshop (ALCW2015)
  • Place of Presentation: つくば、茨城
  • Year and Date: 2015-04-20
  • Int'l Joint Research
• [Presentation] Axion monodromy inflation with modulation corrections (2015)
  • Author(s): Osamu Seto
  • Organizer: 2015 Xth Iberian Cosmology Meeting
  • Place of Presentation: アランフェス、スペイン
  • Year and Date: 2015-03-30
  • Int'l Joint Research
• [Presentation] Aspects of RH sneutrino dark matter with neutrinophilic Higgs field (2014)
  • Author(s): Osamu Seto
  • Organizer: IBS - MultiDark Joint Focus Program: WIMPs and Axions
  • Place of Presentation: 大田、韓国
  • Year and Date: 2014-10-10
  • Int'l Joint Research / Invited
• [Presentation] Axion monodromy inflation with corrections (2014)
  • Author(s): Osamu Seto
  • Organizer: Summer Institute 2014
  • Place of Presentation: 富士カーム
  • Year and Date: 2014-08-21
  • Int'l Joint Research
• [Presentation] Neutrino mass from neutrinophilic Higgs, leptogenesis and dark matter (2014)
  • Author(s): Osamu Seto
  • Organizer: 第三回 次世代の加速器ニュートリノ実験ワークショップ
  • Place of Presentation: 京都大学
  • Year and Date: 2014-06-21
  • Invited