Central exclusive production of $W$ boson pairs in $pp$ collisions at the LHC in hadronic and semi-leptonic final states

TL;DR

This paper investigates the production of W boson pairs in proton-proton collisions at the LHC, focusing on hadronic and semi-leptonic final states, to improve constraints on anomalous gauge couplings using forward proton detectors.

Contribution

It extends previous studies by including hadronic decay channels in the analysis of exclusive W pair production at the LHC, enhancing sensitivity to anomalous quartic gauge couplings.

Findings

Couplings can be probed down to 3.7×10⁻⁷ GeV⁻² for a₀^W

Couplings can be probed down to 9.2×10⁻⁷ GeV⁻² for a_C^W

Combined analysis improves limits compared to leptonic channels alone

Abstract

We present a phenomenology study on central exclusive production of $W^+W^-$ boson pairs in proton-proton collisions at the Large Hadron Collider at 14 TeV using the forward proton detectors, such as the ATLAS Forward Proton or the CMS-TOTEM Precision Proton Spectrometer detectors. Final states where at least one of the $W$ bosons decay hadronically in a large-radius jet are considered. The latter extends previous efforts that consider solely leptonic final states. A measurement of exclusive $W^+W^-$ also allows us to further constrain anomalous quartic gauge boson interactions between photons and $W$ bosons. Expected limits on anomalous quartic gauge couplings $a_{0,C}^W$ associated to dimension-six effective operators are derived for the hadronic, semi-leptonic, and leptonic final states. It is found that the couplings can be probed down to one-dimensional values of $a_{0}^W = 3.7\times 10^{-7}$ GeV$^{-2}$ and $a_{C}^W = 9.2 \times 10^{-7}$ GeV$^{-2}$ at $95\%$ CL at an integrated luminosity of 300 fb$^{-1}$ by combining all final states, compared to values of about $a_{0}^W = 4\times 10^{-6}$ GeV$^{-2}$ and $a_{C}^W = 1\times 10^{-5}$ GeV$^{-2}$ at 95\% CL expected for the leptonic channel alone.