Examining CP Symmetry in Strange Baryon Decays

Abstract

Non-conservation of CP symmetry can manisfest itself in non-leptonic hyperon decays as a difference in the decay parameter between the strange-baryon decay and its charge conjugate. By comparing the decay distribution in the $\Lambda$ helicity frame for the decay sequence ${\Xi }^{-}\to \Lambda {\pi }^{-}$, $\Lambda \to p{\pi }^{-}$ with that of ${\bar{\Xi }}^{+}$ decay, E756 at Fermilab did not observe any CP-odd effect at the $10^{-2}$ level. The status of a follow-up experiment, HyperCP (FNAL E871), to search for CP violation in charged $\Xi -\Lambda$ decay with a sensitivity of $10^{-4}$ is also presented.

arXiv comment9 pages, 4 figures, invited talk presented at the Third International Conference on B Physics and CP Violation, 3-7 Dec 1999, Taipei, Taiwan