A comment on "Amplification of endpoint structure for new particle mass measurement at the LHC"

TL;DR

This paper critically examines the effectiveness of the $m_{CT2}$ variable for measuring new particle masses at the LHC, showing that Standard Model backgrounds reduce its sensitivity compared to other methods.

Contribution

It provides a comparative analysis demonstrating that $m_{CT2}$ is less robust against backgrounds than alternative variables for SUSY mass measurements.

Findings

$m_{CT2}$ sensitivity decreases with Standard Model backgrounds.

Other variables outperform $m_{CT2}$ in mass sensitivity.

Highlights limitations of $m_{CT2}$ in realistic collider environments.

Abstract

We present a comment on the kinematic variable $m_{CT2}$ recently proposed in "Amplification of endpoint structure for new particle mass measurement at the LHC". The variable is designed to be applied to models such as R-parity conserving Supersymmetry (SUSY) when there is pair production of new heavy particles each of which decays to a single massless visible and a massive invisible component. It was proposed in "Amplification of endpoint structure for new particle mass measurement at the LHC" that a measurement of the peak of the $m_{CT2}$ distribution could be used to precisely constrain the masses of the SUSY particles. We show that when Standard Model backgrounds are included in simulations, the sensitivity of the $m_{CT2}$ variable to the SUSY particle masses is more seriously impacted for $m_{CT2}$ than for other previously proposed variables.