New Physics Search via Higgs Particle

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K05415
• 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: Shimane University
• Principal Investigator: Haba Naoyuki 島根大学, 学術研究院理工学系, 教授 (00293803)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: ヒッグス / 標準模型を超える物理

Outline of Final Research Achievements

We have studied physics beyond the Standard Model (BSM) based on the value of the Higgs particle mass. (1)Motivated by the fact that new particles should be introduced to stabilize the Higgs potential up to the Planck scale, we have considered left-right symmetric models and grand unified theories (GUTs), and conducted analyses on new CP violation and gravitational waves generated by a phase transition, and also made predictions on proton decay and lepton flavor mixings. (2)We have constructed a model where the theory has classical scale invariance and a new strongly-coupled gauge theory induces the Higgs potential, and predicted new particles. (3)As a possibility that the SM is replaced by a new theory at the scale of vanishing Higgs quartic coupling, we have constructed a gauge-Higgs unification model where this scale is identified with the compactification scale of the extradimension, and made a prediction on new particles.

Free Research Field

素粒子論

Academic Significance and Societal Importance of the Research Achievements

将来実験でBSMのシグナルが発見された場合それがSMの謎の解決にどう結びつくか示した。例えば、K中間子崩壊のdirect CP violationの理論計算の進展や中性子電気双極子能率の探索によりBSMのシグナルが検知された場合、パリティの破れの起源に迫れることや、陽子崩壊観測やニュートリノ振動の精密測定から、どのようなGUTが電荷の量子化とニュートリノ微小質量を実現しているかヒントが得られることを示した。また、概要②,③の研究で予言された新粒子が発見された場合、ヒッグスポテンシャルの起源として「古典的スケール不変性＋強結合ダイナミクス」や、余剰次元理論といった可能性が示唆されることも示した。