Measurement of the Yukawa coupling in pp collisions with ATLAS detector

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K17633
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: The University of Tokyo
• Principal Investigator: Masubuchi Tatsuya 東京大学, 素粒子物理国際研究センター, 助教 (20512148)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ヒッグス粒子 / 湯川結合 / フェルミオン / ミューオン検出器 / MPGD

Outline of Final Research Achievements

A search for the decay of the Standard model Higgs boson into a bottom quark pair when produced in association with a W or Z boson is performed. The analyzed data, corresponding to an integrated luminosity of approximately 36/fb at a center-of-mass energy of 13 TeV which were collected in the ATLAS detector. An excess of events over the expected background from other Standard Model processes is found with an observed significance 3.5 sigma (an expected significance is 4.0 sigma). The measured signal strength, a ratio of the measured signal yield to the Standard model prediction, was 0.90+/-0.18(stat.)+0.21-0.19(syst.). That is consistent with the Standard model prediction and an evidence for the Higgs boson decay with bottom quark.
The MicroMegas with two dimensional readouts was produced and tested with radioactive sources and cosmic ray. A micro resistive WELL (μ-RWELL) with two dimensional readouts was designed and produced. The first signal was observed with the μ-RWELL.

Free Research Field

高エネルギー実験