Measurement of Higgs Yukawa couplings with the ATLAS experiment

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400294
• 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: University of Tsukuba
• Principal Investigator: HARA Kazuhiko 筑波大学, 数理物質系, 准教授 (20218613)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ヒッグス粒子 / 湯川結合 / LHC / ATLAS / タウレプトン / ボトムクォーク

Outline of Final Research Achievements

Whether the Higgs boson, discovered in 2012 at CERN/LHC, generates the masses to all particles as predicted by the Standard Model? We measured the Higgs Yukawa couplings using the 25/fb of data collected by LHC/ATLAS experiment to shed light on this question.
Paris of the heaviest lepton, tau, are found to be produced via Higgs at a rate μ=1.43+0.43-0.37 normalized by the Standard Model. This corresponds to a significance of 4.5σ and proves for the first time the existence of the Yukawa coupling for the lepton. For the quark, the search covered the production of b-quark pairs via Higgs. The significance was 1.4σ for this mode, and we require more statistics to answer to the question.

Free Research Field

素粒子物理学（実験）