Supersymmetric solution to the KARMEN time anomaly

Abstract

We interpret the KARMEN time anomaly as being due to the production of a (dominantly $b\mathrm{ino})$ neutralino with mass $33.9 \mathrm{MeV},$ which is the lightest supersymmetric particle but decays into 3 leptons through the violation of $R$ parity. For independent gaugino masses ${M}_{1}$ and ${M}_{2}$ we find regions in the ${(M}_{1},$ ${M}_{2},$ $\ensuremath{\mu},$ $\mathrm{tan}\ensuremath{\beta})$ parameter space where such a light neutralino is consistent with all experiments. Future tests of this hypothesis are outlined.