Observation of the Decay Xi^0 --> Sigma^+ mu^- nu(bar)

Abstract

The Xi^0 muon semi-leptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the Xi^0 beta decay mode and yields a value for the ratio of decay rates of $(1.8_{-0.5}^{+0.7}(stat.)\pm 0.2(syst.))\times 10^{-2}$. This is in agreement with the SU(3) flavor symmetric quark model.

4 pages, 4 figures; changed authors list, figure added