Constraining anomalous Higgs boson couplings to virtual photons

TL;DR

This paper investigates anomalous Higgs couplings to virtual photons, proposing methods to handle singularities, calculating widths with these couplings, and analyzing their impact on LHC data within an effective field theory framework.

Contribution

It introduces novel techniques for treating virtual photon singularities and evaluates the effects of anomalous couplings on Higgs decay and production in LHC analyses.

Findings

New approach to handle singularities in Higgs decays to light fermions via photons

Calculation of Higgs width with anomalous photon couplings

Insights into the role of intermediate photons in LHC data analysis

Abstract

We present a study of Higgs boson production in vector boson fusion and in association with a vector boson and its decay to two vector bosons, with a focus on the treatment of virtual loops and virtual photons. Our analysis is performed with the JHU generator framework. Comparisons are made to several other frameworks, and the results are expressed in terms of an effective field theory. New features of this study include a proposal on how to handle singularities involving Higgs boson decays to light fermions via photons, calculation of the partial Higgs boson width in the presence of anomalous couplings to photons, a comparison of the next-to-leading-order electroweak corrections to effects from effective couplings, and phenomenological observations regarding the special role of intermediate photons in analysis of LHC data in the effective field theory framework. Some of these features are illustrated with projections for experimental measurements with the full LHC and HL-LHC datasets.