Measurement of spin correlation coefficients in (p)over-right-arrow (p)over-right-arrow→dπ+ -: art. no. 064604

The spin correlation coefficent combinations A(xx)+A(yy) and A(xx)-A(yy), the spin correlation coefficients A(yz) and A(zz), and the analyzing power were measured for (p) over right arrow (p) over right arrow-->d pi(+) between center-of-mass angles 25 degrees less than or equal to theta less than or equal to 65 degrees at beam energies of 350.5, 375.0, and 400.0 MeV. The experiment was carried out with a polarized internal target and a stored, polarized beam. Nonvertical beam polarization needed for the measurement of A(zz) was obtained by the use of solenoidal spin rotators. Near threshold, only a few partial waves contribute, and pion s and p waves dominate with a possible small admixture of d waves. Certain combinations of the observables reported here are a direct measure of these d waves. The d-wave contributions are found to be negligible even at 400.0 MeV.