Effective Field Theory for Higgs properties parametrisation: the transverse momentum spectrum case

TL;DR

This paper extends the theoretical analysis of the Higgs transverse momentum spectrum within the SMEFT framework, demonstrating how dimension-six operators can cause spectrum distortions and improve sensitivity through higher-order calculations.

Contribution

It provides an NNLL+NNLO calculation of the Higgs pT spectrum including SMEFT operators, enhancing precision and sensitivity for new physics searches.

Findings

Modifications affect the spectrum significantly within current uncertainties.

Higher-order calculations reduce scale uncertainties.

Spectrum distortions can signal new physics beyond the Standard Model.

Abstract

After the Higgs boson discovery, LHC can be used as a precision machine to explore its properties. Indeed, in case new resonances will not be found, the only access to New Physics would be via measuring small deviations from the SM predictions. A consistent approach is provided by a bottom-up Effective Field Theory, with dimension six operators built of Standard Model fields (SMEFT). We discuss how this approach works in case of the transverse momentum spectrum of the Higgs particle. In our calculation we augmented the Standard Model with three additional operators describing modifications of the top and bottom Yukawa couplings, and a point-like Higgs coupling to gluons. Based on recently presented resummed transverse-momentum spectra including these operators at NLL+NLO accuracy,which we recently presented in Ref [1], in this note we show the extension of the calculation to NNLL+NNLO. We find that such modifications, while affecting the total rate within the current uncertainties, can lead to significant distortions of the spectrum. Additionally, through significant reduction of the scale uncertainty we improve the sensitivity to the new operators.