Measuring tau-polarisation in Neutralino2 decays at the LHC

TL;DR

This paper proposes a method to measure tau polarization in neutralino decays at the LHC by analyzing the di-tau mass spectrum, which helps determine SUSY particle couplings and mass endpoints.

Contribution

It introduces a novel approach to extract tau polarization from the di-tau mass spectrum in supersymmetry decays at the LHC.

Findings

Tau polarization can be extracted from the di-tau mass spectrum.

Measurement improves the determination of SUSY particle couplings.

Enhanced accuracy in di-tau mass endpoint estimation.

Abstract

We show how the sum of the two average tau polarisations in the decay chain chi20 -> stau1 tau -> tau tau chi10 in minimal supersymmetry with conserved R-parity can be measured at the LHC. This is accomplished by exploiting the polarisation dependence of the visible di-tau mass spectrum. Such a measurement provides information on the couplings of the involved SUSY particles and allows a more precise determination of the di-tau mass endpoint. If different tau decay modes can be distinguished, the polarisation and endpoint measurement can be improved even further.