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Lightest Supersymmetric electrically charged particle

  1. Jul 7, 2010 #1
    If TeV scale supersymmetry turns out to be true, with R-parity conservation it has been argued the lightest supersymmetric particle would be a great dark matter candidate since it would be stable.

    I'm curious whether a similar argument could be used to say that the "lightest charged" supersymmetric particle would have to be long lived as well. Are there enough constraints on MSSM to estimate an order of magnitude for the lifetime of such a particle?

    EDIT: Okay, I found that such a particle is referred to as the "lightest chargino" which has helped google searches. There are plenty of comments suggesting this could be long lived, but I haven't found much discussion on why or what MSSM predicts yet.
    Last edited: Jul 7, 2010
  2. jcsd
  3. Jul 7, 2010 #2
    It really depends on where you are living in the SUSY parameter space. For example, if you have gauge mediation, the stau (the SUSY partner of the tau lepton) can have a lifetime of a few microseconds, as its decay rate to the gravitino (the LSP) is highly suppressed.

    We know that the lightest charged particle has to decay with a very short lifetime, otherwise the predictions for the abundances of the light elements tend to get screwed up. It can't live too long, either, because we don't see any of it today. Other than that I'm not sure of the bounds.
  4. Jul 7, 2010 #3
    They are called CHAMPs. They exist in some models, but they are severely constrained because they'd accumulate in our oceans in the form of superheavy water, and there are strong bounds (order of 10^-27 or better) on their concentration in the oceans.
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