Enhancing the discovery prospects for SUSY-like decays with a forgotten kinematic variable

TL;DR

This paper explores the use of the kinematic variable Δ₄ to improve the detection of SUSY-like decay events at the LHC, especially in challenging scenarios with large backgrounds and subtle signals.

Contribution

It demonstrates the advantages of using Δ₄ as a discovery variable and shows how pairing it with other invariant mass variables enhances detection sensitivity.

Findings

Δ₄ effectively characterizes four-body phase space boundaries

Pairing Δ₄ with other variables improves signal discrimination

Significant enhancement over conventional analysis techniques

Abstract

The lack of a new physics signal thus far at the Large Hadron Collider motivates us to consider how to look for challenging final states, with large Standard Model backgrounds and subtle kinematic features, such as cascade decays with compressed spectra. Adopting a benchmark SUSY-like decay topology with a four-body final state proceeding through a sequence of two-body decays via intermediate resonances, we focus our attention on the kinematic variable $\Delta_{4}$ which previously has been used to parameterize the boundary of the allowed four-body phase space. We highlight the advantages of using $\Delta_{4}$ as a discovery variable, and present an analysis suggesting that the pairing of $\Delta_{4}$ with another invariant mass variable leads to a significant improvement over more conventional variable choices and techniques.