Probing natural SUSY from stop pair production at the LHC

TL;DR

This paper investigates the potential to detect stop squark pair production in natural supersymmetry at the LHC, analyzing parameter space constraints and simulating signals to determine discovery and exclusion limits.

Contribution

It provides a detailed analysis of stop pair production prospects in natural MSSM, including parameter scans, decay mode studies, and Monte Carlo simulations for LHC detection capabilities.

Findings

LHC at 14 TeV and 100 fb^{-1} can discover stops up to 450 GeV.

Stop decay modes into top-neutralino and bottom-chargino are complementary for detection.

Exclusion limits can reach around 537 GeV if no signal is observed.

Abstract

We consider the natural supersymmetry scenario in the framework of the R-parity conserving minimal supersymmetric standard model (called natural MSSM) and examine the observability of stop pair production at the LHC. We first scan the parameters of this scenario under various experimental constraints, including the SM-like Higgs boson mass, the indirect limits from precision electroweak data and B-decays. Then in the allowed parameter space we study the stop pair production at the LHC followed by the stop decay into a top quark plus a lightest neutralino or into a bottom quark plus a chargino. From detailed Monte Carlo simulations of the signals and backgrounds, we find the two decay modes are complementary to each other in probing the stop pair production, and the LHC with $\sqrt{s}= 14$ TeV and 100 $fb^{-1}$ luminosity is capable of discovering the stop predicted in natural MSSM up to 450 GeV. If no excess events were observed at the LHC, the 95% C.L. exclusion limits of the stop masses can reach around 537 GeV.