Probing Electroweak Precision Physics via boosted Higgs-strahlung at the LHC

TL;DR

This paper investigates how high-energy Higgs-strahlung processes at the LHC, analyzed with advanced subjet techniques, can improve constraints on certain SMEFT operators beyond previous LEP bounds.

Contribution

It demonstrates that high-energy measurements of Higgs-strahlung with subjet techniques can significantly tighten bounds on specific SMEFT operators.

Findings

High-energy Higgs-strahlung probes four key SMEFT directions.

Subjet techniques enhance Higgs reconstruction accuracy.

LHC bounds surpass existing LEP constraints by an order of magnitude.

Abstract

We study the process $pp \to Z(\ell^+ \ell^-)h(b\bar b)$ in the Standard Model Effective Field Theory (SMEFT) at high energies using subjet techniques to reconstruct the Higgs boson. We show that at high energies this process probes four directions in the dimension 6 EFT space, namely the operators that contribute to the four contact interactions, $hZ_\mu \bar{f}\gamma^\mu f$, where $f=u_L, u_R,d_L$ and $d_R$. These four directions are, however, already constrained by the $Z$-pole and diboson measurements at LEP. We show that by utilising the energy growth of this process in the SMEFT and the accuracy that can be achieved by using subjet techniques at the High Luminosity LHC, one can obtain bounds on these operators that are an order of magnitude better than existing LEP bounds.