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.