A flexible and efficient approach for missing transverse momentum reconstruction

TL;DR

This paper introduces a new, flexible method for reconstructing missing transverse momentum in collider experiments, improving precision and efficiency by integrating pileup suppression, energy calibration, and systematic variations.

Contribution

It presents a novel approach that efficiently encodes information for missing transverse momentum calculation, adaptable to various selection criteria and experimental conditions.

Findings

Enhanced reconstruction accuracy in collider data

Effective pileup suppression using calorimeter and inner detector data

Optimized missing transverse momentum use in LHC analyses

Abstract

Missing transverse momentum is a crucial observable for physics at hadron colliders, being the only constraint on the kinematics of "invisible" objects such as neutrinos and hypothetical dark matter particles. Computing missing transverse momentum at the highest possible precision, particularly in experiments at the energy frontier, can be a challenging procedure due to ambiguities in the distribution of energy and momentum between many reconstructed particle candidates. This paper describes a novel solution for efficiently encoding information required for the computation of missing transverse momentum given arbitrary selection criteria for the constituent reconstructed objects. Pileup suppression using information from both the calorimeter and the inner detector is an integral component of the reconstruction procedure. Energy calibration and systematic variations are naturally supported. Following this strategy, the ATLAS Collaboration has been able to optimise the use of missing transverse momentum in diverse analyses throughout Runs 2 and 3 of the Large Hadron Collider and for future analyses.