Light-quark Yukawa couplings from off-shell Higgs production

Abstract

Abstract Yukawa couplings of the first quark generation are notoriously difficult to constrain due to their small values within the Standard Model. Here we propose Higgs off-shell production, with the Higgs boson decaying to four leptons, as a probe of the up- and down-quark Yukawa couplings. Using kinematic discriminants similar to the ones employed in the Higgs width measurements we find that the down (up) Yukawa coupling can be constrained to a factor of 156 (260) times its Standard Model value at the high-luminosity LHC assuming only experimental systematic uncertainties. Off-shell Higgs production hence provides better sensitivity to the first-generation quark Yukawa couplings with respect to other probes such as Higgs+jet or Higgs pair production.

Keywords

• Anomalous Higgs Couplings
• Higgs Properties
• SMEFT