Could $M_{T2}$ be a singularity variable?

TL;DR

This paper explores the relationship between the algebraic singularity method's variables and the $M_{T2}$ variable in collider physics, revealing that singularity variables often encompass $M_{T2}$ but are not identical.

Contribution

It demonstrates that singularity variables frequently include $M_{T2}$ in double-sided decay topologies, clarifying their connection and potential for analyzing missing energy events.

Findings

Singularity variables often contain $M_{T2}$ in many cases.

The algebraic singularity method offers a framework for analyzing missing energy events.

$M_{T2}$ is not a strict subset of singularity variables.

Abstract

The algebraic singularity method is a framework for analyzing collider events with missing energy. It provides a way to draw out a set of singularity variables that can catch singular features originating from the projection of full phase space onto the observable phase space of measured particle momenta. It is a promising approach applicable to various physics processes with missing energy but still requires more studies for use in practice. Meanwhile, in the double-sided decay topology with an invisible particle on each side, the $M_{T2}$ variable has been known to be a useful collider observable for measuring particle masses from missing energy events or setting signal regions of collider searches. We investigate the relation between the two different types of kinematic variables in double-sided decay topology. We find that the singularity variables contain the $M_{T2}$ variable in many cases, although the former is not a strict superset of the latter.