INCLUSIVE REACTIONS WITH THREE POLARIZED PARTICLES

Abstract

In the reaction p+p→Λ+X with up to all three known particles polarized (which will be studied in Fermilab’s upcoming polarization facility) the relationship of the various polarization observables to the 20 three-in-three-out amplitudes is simply given by two 4-by-4 and 12 2-by-2 submatrices. The QCD predictions are said to be the firmest in the large momentum transfer region. There, in the lowest order perturbative calculations only two amplitudes are nonzero, thus yielding only six nonzero polarization quantities with four relations among them. For smaller momentum transfers, Regge model predictions for double correlation observables may be tested even though such models have failed to predict the large single Λ polarization which has been the subject of so much speculation in recent years. The three models which attempt to explain this large polarization can also be tested in these reactions with up to three polarized particles since they should yield small asymmetries for the incident particles. All in all, such polarization experiments will significantly strengthen the testing of the various proposed theoretical models.