Modeling BSM effects on the Higgs transverse-momentum spectrum in an EFT approach

TL;DR

This paper develops a precise theoretical model for the Higgs boson transverse-momentum spectrum in gluon fusion, incorporating potential new physics effects via dimension-six operators, and highlights their impact on experimental analyses at the LHC.

Contribution

It introduces a combined resummation and NLO matching framework for the Higgs pT spectrum including EFT operators, providing a tool for probing new physics effects.

Findings

Modifications from EFT operators can significantly distort the Higgs pT spectrum.

Total rate uncertainties currently mask some new physics effects.

Proper parametrization of these effects is crucial for LHC Run II analyses.

Abstract

We consider the transverse-momentum distribution of a Higgs boson produced through gluon fusion in hadron collisions. At small transverse momenta, the large logarithmic terms are resummed up to next-to-leading-logarithmic (NLL) accuracy. The resummed computation is consistently matched to the next-to-leading-order (NLO) result valid at large transverse momenta. The ensuing Standard Model prediction is supplemented by possible new-physics effects parametrised through three dimension-six operators related to the modification of the top and bottom Yukawa couplings, and to the inclusion of a point-like Higgs-gluon coupling, respectively. We present resummed transverse-momentum spectra including the effect of these operators at NLL+NLO accuracy and study their impact on the shape of the distribution. We find that such modifications, while affecting the total rate within the current uncertainties, can lead to significant distortions of the spectrum. The proper parametrization of such effects becomes increasingly important for experimental analyses in Run II of the LHC.