Constraining SMEFT operators with associated hγ production in weak boson fusion

Anke Biekötter,Raquel Gomez-Ambrosio,Parisa Gregg,Frank Krauss,Marek Schönherr

doi:10.1016/j.physletb.2021.136079

Anke Biekötter, Raquel Gomez-Ambrosio + Show 3 more

Open Access

https://doi.org/10.1016/j.physletb.2021.136079

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Journal: Physics Letters B	Publication Date: Jan 18, 2021
Citations: 83	License type: cc-by

Affiliation: Durham University

Abstract

We consider the associated production of a Higgs boson and a photon in weak boson fusion in the Standard Model (SM) and the Standard Model Effective Field Theory (SMEFT), with the Higgs boson decaying to a pair of bottom quarks. Analysing events in a cut-based analysis and with multivariate techniques we determine the sensitivity of this process to the bottom-Yukawa coupling in the SM and to possible CP-violation mediated by dimension-6 operators in the SMEFT.

Highlights

The observation of the Higgs boson in 2012 [1, 2] initiated intense efforts to measure its properties in a wide range of production and decay processes, to either confirm it as the Higgs boson predicted by the Standard Model, or to catch first glimpses of new physics beyond it
We study the associated production of a Higgs boson with a photon in weak boson fusion (WBF), manifesting itself in a final state consisting of the two bosons and two forward jets
We further investigate the impact of possible effects of beyond the Standard Model physics in WBF hγ production, using the language of effective dimension-six operators from the Standard Model Effective Theory (SMEFT) [8,9,10,11,12]

Summary

Introduction

The observation of the Higgs boson in 2012 [1, 2] initiated intense efforts to measure its properties in a wide range of production and decay processes, to either confirm it as the Higgs boson predicted by the Standard Model, or to catch first glimpses of new physics beyond it. Background contributions to the signal final-state feature the direct production of b-jets in the simulation, necessitating additional generation-level cuts. We consider O(αs4α) contibutions which we denote QCD and electroweak (EW) Zγjj production with the Z boson decaying to b-quarks, with the following additional cuts on the b’s: pT,b > 20 GeV, mbb ∈ [90, 200] GeV, (2) ∆Rγb > 0.4, ∆Rjb > 0.4 , We have explicitly checked that the contributions from O(αs2α3) are negligible at the 5% level and O(αs3α2) as well as O(αsα4) contribute less than 1% each. We require the invariant b-jet mass to be close to the Higgs mass mbb ∈ [100, 140] GeV

Determination of the b-Yukawa coupling

Selection of operators

CP structure of the EFT and observable consequences

Findings

Conclusions and Outlook