Impact of fermionic operators on the Higgs width measurement

TL;DR

This paper investigates how anomalous fermionic Z couplings influence the Higgs width measurement via off-shell Higgs production at the LHC, highlighting their potential impact despite existing constraints.

Contribution

It provides a detailed analysis of the effects of anomalous Z-fermion couplings on Higgs width measurements, considering current and future collider scenarios.

Findings

Anomalous Z-fermion couplings can significantly affect Higgs width measurements at LHC Runs 2 and 3.

Constraints from electroweak precision data limit the impact of these couplings.

At high luminosity LHC, the effect of anomalous couplings on the Higgs width is negligible.

Abstract

The off-shell Higgs production in pp -> ZZ at LHC provides at present the most direct measurement of the Higgs width in the absence of beyond the standard model contributions. Here, we analyze the impact of anomalous Z couplings to fermions on the Higgs width determination. We show that, despite these couplings being strongly constrained by the available electroweak precision data, they can substantially affect the Higgs width determination at the LHC Runs 2 and 3. Conversely, in larger integrated luminosities runs, such as those foreseen at the high luminosity LHC and high energy LHC setups, the effect of such anomalous interactions in the Higgs width measurement is minimal.