Electroweak Phase Transition and Higgs Physics

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05057
• 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: Saga University
• Principal Investigator: Funakubo Koichi 佐賀大学, 工学(系)研究科(研究院), 教授 (60221553)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 電弱相転移 / スファレロン過程 / ヒッグス粒子の物理

Outline of Final Research Achievements

To judge the possibility of the electroweak baryogensis (EWBG) in the framework of the BSM, the EW phase transition must be a strongly first-order one. The SM is known to have a cross over for the phase change.
In this project, we attempted to improve the precision to determine the condition for the EWBG by considering the resummation of the thermal mass without use of the high-temperature expansion in a gauge-invariant way based on a method which was developed for the abelian gauge theory by us. We also studied the effect of the band structure in the effective theory describing the quantum tunneling between the adjacent classical vacua of the bosonic sector of an EW theory, pointed by Tye and Wong. We reformulated the effective theory in a gauge-invariant way to avoid the divergence in the mass parameter and improved the precision of the energy band structure by use of 3 different WKB methods.

Free Research Field

素粒子論