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arXiv · 1003.4540

Long-lived stops in MSSM scenarios with a neutralino LSP

M. Johansen·J. Edsjo·S. Hellman·D. Milstead
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Abstract

This work investigates the possibility of a long-lived stop squark in supersymmetric models with the neutralino as the lightest supersymmetric particle (LSP). We study the implications of meta-stable stops on the sparticle mass spectra and the dark matter density. We find that in order to obtain a sufficiently long stop lifetime so as to be observable as a stable R-hadron at an LHC experiment, we need to fine tune the mass degeneracy between the stop and the LSP considerably. This increases the stop-neutralino coanihilation cross section, leaving the neutralino relic density lower than what is expected from the WMAP results for stop masses ~1.5 TeV/c^2. However, if such scenarios are realised in nature we demonstrate that the long-lived stops will be produced at the LHC and that stop-based R-hadrons with masses up to 1 TeV/c^2 can be detected after one year of running at design luminosity.

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M. Johansen, J. Edsjo, S. Hellman, D. Milstead. 2010-03-23. Long-lived stops in MSSM scenarios with a neutralino LSP. https://doi.org/10.1007/jhep08(2010)005

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