Spin transfer in exclusive Lambda production from (p)over-right-arrowp collisions at 3.67 GeV/c

We report the first polarization transfer measurements for exclusive hyperon production reactions. The normal spin transfer coefficient D-NN for (p) over right arrow p --> pK(+)<(Lambda)over right arrow> is large and negative for forward Lambda production at a beam momentum of 3.67 GeV/c, a result qualitatively consistent with expectations for a mechanism dominated by kaon exchange and rescattering. The sign of D-NN is opposite to that observed in the fragmentation regime for inclusive Lambda production at much higher energies.