Result of T-violating muon polarization measurement in the $K^{+}\to {\pi }^0{\mu }^{+}\nu$ decay

Abstract

A search for T-violating muon polarization in the $K^{+}\to {\pi }^0{\mu }^{+}\nu$ decay has been performed at KEK using stopped kaons. A new improved limit was obtained, $P_T=-0.0017\pm 0.0023(stat)\pm 0.0011(syst)$, corresponding to a 90 % confidence limit of $|P_T|<0.0050$. The T-violating parameter was also determined to be Im$\xi =-0.0053\pm 0.0071(stat)\pm 0.0036(syst)$, and $|rmIm\xi |<0.016$ (90 % CL).

10 pages, 4 figures, XXXIXth Rencontres de Moriond, Electroweak Interactions and Unified Theories, La Thuile, Italy, March 21-28, 2004