Modified Signals for Supersymmetry in the NMSSM with a Singlino-like LSP

TL;DR

This paper investigates how the presence of a singlino-like LSP in the NMSSM alters supersymmetry search efficiencies at the LHC, showing significant reductions in missing energy signals and implications for current bounds.

Contribution

It provides a quantitative analysis of the impact of bino to singlino cascades on search efficiencies in the NMSSM, extending previous MSSM-based studies.

Findings

Bino to singlino cascades reduce missing energy signatures.

Search efficiencies can decrease by factors of 1/3 to 1/7.

Lower bounds on M_{1/2} can be relaxed by up to 25-50%.

Abstract

In the framework of the NMSSM with a singlino-like LSP, we study quantitatively the impact of the additional bino -> singlino cascade on the efficiencies in several search channels for supersymmetry of the ATLAS and CMS collaborations. Compared to the MSSM, the additional cascade reduces the missing transverse energy, but leads to additional jets or leptons. For the NMSSM benchmark lines which generalize cMSSM benchmark points, the efficiencies in the most relevant 2/3 jet + missing energy search channels can drop by factors ~1/3 to ~1/7, and can reduce the present lower bounds on M_{1/2} by as much as ~0.9 - 0.75 in the NMSSM for large bino-singlino mass differences. The larger efficiencies in multijet or multilepton search channels are not strong enough to affect this conclusion. In the fully constrained cNMSSM, sparticle decay cascades via the lightest stau can lead to signal cross sections in multilepton and 2tau search channels which are potentially visible at the LHC with 7 TeV center of mass energy.