Triply polarized $WWW$ at the LHC: first glimpse at LO

TL;DR

This paper provides the first leading-order analysis of triply polarized $WWW$ events at the LHC, revealing polarization fractions and discussing measurement challenges and a new on-shell mapping method.

Contribution

It introduces the first LO calculation of triply polarized $WWW$ production at the LHC, including a new on-shell mapping technique for polarized cross-section computations.

Findings

Triply-transverse polarization fraction is about 51%.

Triply-longitudinal (LLL) fraction is approximately 1.4%.

Interference between polarization amplitudes is +1.8%.

Abstract

We present first results for triply polarized $WWW$ events at the LHC. The calculation is performed at leading order for fully leptonic decays using the Standard Model. Employing an inclusive kinematic cut setup, we found that the triply-transverse polarization fraction is about $51\%$, while the triply-longitudinal (LLL) fraction is smallest with $1.4\%$ for the $W^-W^+W^+$ process. The interference between different polarization amplitudes amounts to $+1.8\%$. Results for the $W^+W^-W^-$ case are similar. Based on known higher-order results for the diboson processes, radiative corrections are not expected to increase the LLL fraction to the level of tens of percent. This means that measuring the LLL cross section at the LHC will be very challenging. A new on-shell mapping for triboson processes, being a crucial element of polarized cross-section calculation, is also presented.