Top Polarization and Stop Mixing from Boosted Jet Substructure

TL;DR

This paper develops a detector-level method to measure top polarization from boosted jet substructure, enabling constraints on supersymmetric parameters and distinguishing stop masses at the LHC.

Contribution

It introduces a novel analysis technique for extracting top polarization from boosted jets, linking it to supersymmetric parameters like A_t.

Findings

Can distinguish 600 GeV stops to 4σ with 100 fb^(-1)

Can distinguish 800 GeV stops to 3σ with 100 fb^(-1)

Provides a new tool for probing supersymmetry at the LHC

Abstract

Top polarization is an important probe of new physics that couples to the top sector, and which may be discovered at the 14 TeV LHC. Taking the example of the MSSM, we argue that top polarization measurements can put a constraint on the soft supersymmetry breaking parameter A_t. In light of the recent discovery of a Higgs-like boson of mass ~125 GeV, a large A_t is a prediction of many supersymmetric models. To this end, we develop a *detector level* analysis methodology for extracting polarization information from hadronic tops using boosted jet substructure. We show that with 100 fb^(-1) of data, left and right 600 GeV stops can be distinguished to 4\sigma, and 800 GeV stops can be distinguished to 3\sigma.