Long-lived neutralino NLSPs

  • Patrick Meade
  • Matthew Reece
  • David Shih


We investigate the collider signatures of heavy, long-lived, neutral particles that decay to charged particles plus missing energy. Specifically, we focus on the case of a neutralino NLSP decaying to Z and gravitino within the context of General Gauge Mediation. We show that a combination of searches using the inner detector and the muon spectrometer yields a wide range of potential early LHC discoveries for NLSP lifetimes () ranging from 10−1 − 105 mm. We further show that events from Z( + ) can be used for detailed kinematic reconstruction, leading to accurate determinations of the neutralino mass and lifetime. In particular, we examine the prospects for detailed event study at ATLAS using the ECAL (making use of its timing and pointing capabilities) together with the TRT, or using the muon spectrometer alone. Finally, we also demonstrate that there is a region in parameter space where the Tevatron could potentially discover new physics in the delayed Z( + ) + Open image in new window channel. While our discussion centers on gauge mediation, many of the results apply to any scenario with a long-lived neutral particle decaying to charged particles.


Supersymmetry Phenomenology 


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Copyright information

© SISSA, Trieste, Italy 2010

Authors and Affiliations

  1. 1.C.N. Yang Institute for Theoretical PhysicsStony Brook UniversityStony BrookU.S.A.
  2. 2.Princeton Center for Theoretical SciencePrinceton UniversityPrincetonU.S.A.
  3. 3.Institute for Advanced StudyPrincetonU.S.A.
  4. 4.Department of Physics and AstronomyRutgersPiscatawayU.S.A.

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