Long-lived stops in MSSM scenarios with a neutralino LSP



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 co-anihilation cross section, leaving the neutralino relic density lower than what is expected from the WMAP results for stop masses ≲1.5 TeV/c2. 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/c2 can be detected after one year of running at design luminosity.


Supersymmetry Phenomenology 


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Copyright information

© SISSA, Trieste, Italy 2010

Authors and Affiliations

  • M. Johansen
    • 1
  • J. Edsjö
    • 1
  • S. Hellman
    • 1
  • D. Milstead
    • 1
  1. 1.Department of Physics and the Oskar Klein Centre for Cosmoparticle PhysicsStockholm UniversityStockholmSweden

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