Search for right-handed currents in the decay K-italic/sup +/. --> mu. /sup +/. nu

The longitudinal polarization of the muon emitted in the decay K-italic/sup +/..--> mu../sup +/..nu.. was measured to search for right-handed weak currents in a strangeness-changing process. The 236-MeV/c-italic muons from the decay of stopped K-italic/sup +/ were identified and were collected by a magnetic spectrometer. The muons were then slowed down in a carbon degrader and were brought to rest in an aluminum target. The muon spins were precessed by a 220-G transverse field, and a muon-spin-rotation technique was employed to measure the muon-spin polarization. The polarization was determined to be -0.970 +- 0.047, which is consistent with the V-italic-A-italic hypothesis.