Evidence for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>Δ</mml:mi><mml:mi>S</mml:mi><mml:mo>=</mml:mo><mml:mo>−</mml:mo><mml:mi>Δ</mml:mi><mml:mi>Q</mml:mi></mml:math>Currents or Charmed-Baryon Production by Neutrinos

We report on the production by neutrinos of an event with negative strangeness. In an exposure of the Brookhaven National Laboratory 7-ft cryogenic bubble chamber to a broad-band neutrino beam 335 events were observed, one of which fits the reaction $\ensuremath{\nu}p\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}{\ensuremath{\Lambda}}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$. Alternative explanations are examined and none found with a probability greater than 3 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}5}$. The event thus represents a large violation of the $\ensuremath{\Delta}S=\ensuremath{\Delta}Q$ rule or alternatively the production and decay of a charmed baryon state. The most plausible mass for this state is found to be 2426 \ifmmode\pm\else\textpm\fi{} 12 MeV.