On sgoldstino interpretation of HyperCP events

Abstract

We discuss possible sgoldstino interpretation of the observation, reported by HyperCP collaboration, of three $\Sigma^+\to p\mu^+\mu^-$ decay events with dimuon invariant mass 214.3 MeV within detector resolution. We find that this interpretation is consistent in models with (i) parity conservation in sgoldstino interactions, (ii) pseudoscalar sgoldstino $P$ of mass 214 MeV and heavier scalar sgoldstino, and (iii) low supersymmetry breaking scale, \sqrt{F} = 2.5-60 TeV. In these models, sgoldstino can be observed in decays $K^+\to\pi^+\pi^0 P$, $K_L\to\pi\pi P$ and $K_S\to\pi\pi P$ at the branching ratios of at least of order 10^{-12}, 10^{-8} and 10^{-11}, respectively. The model can be probed also at e^+e^- colliders in the channels $e^+e^-\to\gamma P$ and $e^+e^-\to e^+e^-P$, where the cross section is likely to be in the range 1 pb - 5 ab.