MEASUREMENT OF THE SPIN-ROTATION PARAMETER A(+) IN ELASTIC PI(+)P SCATTERING AT 1.43 GEV C/

The first data on the spin-rotation parameter A(+) in elastic pi(+)p s cattering in the second resonance region is reported. The measurements were carried out by the PINP-ITEP Collaboration at the ITEP synchrotr on, The experiments were performed with 1.43-GeV/c pions for scatterin g angles theta(c.m.s.) = 127 and 133 degrees. A polarized target with horizontally oriented spin and a graphite polarimeter with spark chamb ers and a TV readout were used. Our experimental results agree with th e predictions of a partial-wave analysis performed at Virginia Polytec hnic Institute and contradict the predictions of the Karlsruhe-Helsink i and Carnegie-Mellon-University analyses.