Road toward the next standard model explored with muon precision physics

• Project/Area Number: 16K05323
• 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: High Energy Accelerator Research Organization (2017-2018); Kagawa National College of Technology (2016)
• Principal Investigator: Nomura Daisuke 大学共同利用機関法人高エネルギー加速器研究機構, 素粒子原子核研究所, 研究員 (40583555)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: ミューオン / 異常磁気能率 / 素粒子の標準模型 / 強い相互作用 / 標準模型を超える物理 / 素粒子論 / 原子・分子物理

Outline of Final Research Achievements

We have reevaluated the hadronic leading-order contribution to the muon g-2, which has the largest uncertainty in the Standard Model prediction for the muon g-2. Compared to our previous analysis, we have included new input data, have reevaluated the uncertainties associated with radiative corrections to the hadronic data, and have improved the way to combine various hadronic data. Our main conclusion is that there is a 3.7 sigma discrepancy between the experimental value of the muon g-2 and the Standard Model prediction, which may be a hint of new physics beyond the Standard Model.

Academic Significance and Societal Importance of the Research Achievements

素粒子の標準模型を超える新物理が存在するかどうかは素粒子物理学において大きな問題である。我々の得た結果はミューオンの異常磁気能率について標準模型の予言する値と実験値とがあまりよく一致しないことを意味しており、これによって標準模型を超える新物理が存在する可能性はさらに高まったと言える。

Research Products

• [Int'l Joint Research] University of Liverpool(英国)
• [Int'l Joint Research] Universidade de Sao Paulo(ブラジル)
• [Int'l Joint Research] Universitat Autonoma de Barcelona(スペイン)
• [Int'l Joint Research] San Francisco State University(米国)
• [Int'l Joint Research] York University/University of Victoria/University of British Columbia(カナダ)
• [Int'l Joint Research]
• [Int'l Joint Research] University of Liverpool(英国)
• [Int'l Joint Research] University of Liverpool(United Kingdom)
• [Journal Article] A New Approach for Measuring the Muon Anomalous Magnetic Moment and Electric Dipole Moment (2019)
  • Author(s): M. Abe, S. Bae, G. Beer, （途中50名省略）, D. Nomura, （以下省略。全96名）
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 印刷中
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Muon g‐2 and alpha: A new data‐based analysis (2018)
  • Author(s): Alexander Keshavarzi, Daisuke Nomura, Thomas Teubner
  • Journal Title: Physical Review D Volume: 97 Issue: 11 Pages: 114025-114025
  • DOI: 10.1103/physrevd.97.114025
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Strong coupling from e^+ e^‐ ‐‐> hadrons below charm (2018)
  • Author(s): Diogo Boito, Maarten Golterman, Alexander Keshavarzi, Kim Maltman, Daisuke Nomura, Santiago Peris, Thomas Teubner
  • Journal Title: Physical Review D Volume: 98 Issue: 7 Pages: 074030-074030
  • DOI: 10.1103/physrevd.98.074030
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The muon g-2 and \alpha(M_Z^2): a new data-based analysis (2018)
  • Author(s): Alexander Keshavarzi, Daisuke Nomura, and Thomas Teubner
  • Journal Title: Physical Review D Volume: 印刷中
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Muon g-2: a new data-based analysis (2019)
  • Author(s): D. Nomura
  • Organizer: international worksop "e^+ e^- Collisions From Phi to Psi 2019 (Phipsi19)"
  • Int'l Joint Research / Invited
• [Presentation] ミューオン異常磁気能率に対する標準理論計算:最近の進展 (2019)
  • Author(s): 野村大輔
  • Organizer: 日本物理学会 第 74 回年次大会
  • Invited
• [Presentation] Standard Model prediction for the muon g-2 (2018)
  • Author(s): D. Nomura
  • Organizer: The 20th International Workshop on Neutrinos from Accelerators (NuFACT 2018)
  • Int'l Joint Research / Invited
• [Presentation] Muon g-2: a new data-based anlysis (2018)
  • Author(s): D. Nomura
  • Organizer: 2018 WPI-next mini-workshop ‘Hints for New Physics in Heavy Flavors’
  • Int'l Joint Research / Invited
• [Presentation] Hadronic vacuum polarization contribution to the muonium HFS and related topics (2018)
  • Author(s): D. Nomura
  • Organizer: worksop “Physics of muonium and related topics”
  • Int'l Joint Research / Invited
• [Presentation] muon g-2 の理論 (2018)
  • Author(s): 野村大輔
  • Organizer: Flavor Physics Workshop 2018
  • Invited
• [Presentation] Hadronic Leading Order Contribution to the Muon g-2 (2017)
  • Author(s): Daisuke Nomura
  • Organizer: International Workshop on Flavour changing and conserving processes (FCCP 2017)
  • Int'l Joint Research / Invited
• [Presentation] Improved and updated Standard Model prediction for muon g-2 (2017)
  • Author(s): 野村大輔, A. Keshavarzi, T. Teubner
  • Organizer: 日本物理学会 2017 年秋季大会
• [Presentation] Standard Model prediction for neutron EDM revisited (2017)
  • Author(s): Daisuke Nomura
  • Organizer: RCNP workshop on Fundamental Physics using Neutrons and Atoms
  • Int'l Joint Research
• [Presentation] Hadronic Contributions to Muon g-2 (2016)
  • Author(s): Daisuke Nomura
  • Organizer: workshop "Towards high precision muon g-2/EDM measurement at J-PARC"
  • Place of Presentation: J-PARC, Tokai, Ibaraki, Japan
  • Year and Date: 2016-11-28
  • Int'l Joint Research / Invited
• [Presentation] Hadronic contributions to muon g-2 (2016)
  • Author(s): Daisuke Nomura
  • Organizer: The 6th KIAS Workshop on Particle Physics and Cosmology and the 2nd Durham-KEK-KIPMU-KIAS Joint Workshop
  • Place of Presentation: KIAS, Seoul, South Korea
  • Year and Date: 2016-10-24
  • Int'l Joint Research / Invited
• [Presentation] Status of Calculation of \alpha_{QED}(M_Z^2) and muon g-2 (2016)
  • Author(s): Daisuke Nomura
  • Organizer: workshop "Precision theory for precise measurements at the LHC and future colliders''
  • Place of Presentation: Quy Nhon, Vietnam
  • Year and Date: 2016-09-25
  • Int'l Joint Research / Invited