On polarization parameters of spin-$1$ particles and anomalous couplings in $e^+e^-\to ZZ/Z\gamma$

TL;DR

This paper investigates the polarization asymmetries of Z bosons in electron-positron collisions to set limits on anomalous gauge couplings, providing a comprehensive analysis using MCMC at 500 GeV.

Contribution

It introduces a complete set of polarization asymmetries for Z bosons to constrain anomalous couplings in $e^+e^- o ZZ/Z ext{ }\gamma$ processes, employing MCMC for simultaneous limits.

Findings

Limits on anomalous couplings are $1 ext{ to }3 imes 10^{-3}$ at 500 GeV.

Polarization asymmetries effectively constrain anomalous gauge interactions.

The method provides a comprehensive approach for future collider analyses.

Abstract

We study the anomalous trilinear gauge couplings of $Z$ and $\gamma$ using a complete set of polarization asymmetries for the $Z$ boson in $e^+e^-\to ZZ/Z\gamma$ processes with unpolarized initial beams. We use these polarization asymmetries, along with the cross section, to obtain a simultaneous limit on all the anomalous couplings using the Markov-Chain--Monte-Carlo (MCMC) method. For an $e^+e^-$ collider running at $500$ GeV center-of-mass energy and $100$ fb$^{-1}$ of integrated luminosity the simultaneous limits on the anomalous couplings are $1\sim3\times 10^{-3}$.