Simplified Models for a First Characterization of New Physics at the LHC

TL;DR

This paper introduces four simplified models with minimal parameters to characterize potential new physics signals at the LHC, aiding interpretation of excess events in a model-independent way.

Contribution

It proposes a set of four simplified models with limited parameters for initial data characterization at the LHC, facilitating model-independent analysis of new physics signals.

Findings

Provides a basis for fitting LHC data with simplified models

Enables quantitative analysis of jet and lepton signatures

Serves as a target for full theoretical model comparisons

Abstract

Low-energy SUSY and several other theories that address the hierarchy problem predict pair-production at the LHC of particles with Standard Model quantum numbers that decay to jets, missing energy, and possibly leptons. If an excess of such events is seen in LHC data, a theoretical framework in which to describe it will be essential to constraining the structure of the new physics. We propose a basis of four deliberately simplified models, each specified by only 2-3 masses and 4-5 branching ratios, for use in a first characterization of data. Fits of these simplified models to the data furnish a quantitative presentation of the jet structure, electroweak decays, and heavy-flavor content of the data, independent of detector effects. These fits, together with plots comparing their predictions to distributions in data, can be used as targets for describing the data within any full theoretical model.