Long-lived unstable superparticles at the LHC

Koji Ishiwata,Takumi Ito,Takeo Moroi

doi:10.1016/j.physletb.2008.09.024

Abstract

In various models of supersymmetry (SUSY), the lightest superparticle in the minimal SUSY standard model sector, which we call MSSM-LSP, becomes unstable. Then, we may observe the decay of the MSSM-LSP in the detector at the LHC experiment. We show that the discovery of such a decay process (and the determination of the lifetime of the MSSM-LSP) may be possible at the LHC even if the decay length of the MSSM-LSP is much longer than the size of the detector; sizable number of the MSSM-LSPs decay inside the detector if the lifetime is shorter than 10−(3–5) s. We also discuss the implications of the study of the MSSM-LSP decay for several well-motivated SUSY models.

Highlights

In various models of supersymmetry (SUSY), the lightest superparticle in the minimal SUSY standard model sector, which we call MSSM-LSP, becomes unstable
In many of the studies, it is assumed that R-parity is conserved, and that the lightest superparticle (LSP) is the lightest neutralino
In the gauge-mediated model, the gravitino becomes the LSP and the MSSM-LSP decays into the gravitino

Summary

Introduction

In various models of supersymmetry (SUSY), the lightest superparticle in the minimal SUSY standard model sector, which we call MSSM-LSP, becomes unstable. 4. From the event samples, we calculate the number of the MSSM-LSP decay inside the detector as a function of τ . When the lifetime is shorter than 10−(3−5) sec, the number of the decay of the MSSM-LSP inside the detector turns out to be larger than ∼ O(1).

Results

Conclusion