Experimental study of the reactions pp-+ and K-K+ between 360 and 760 MeV/c

The folded differential cross sections dd)+dd(-,), where, is the center-of-mass angle of the negatively charged outgoing particle, have been measured for the reactions p»p-+ and K-K+ at 15 incident beam momenta between 360 and 760 MeV/c with much better statistics than previous experiments. The total cross sections for these reactions, -+ and -+, have also been obtained by integrating the folded differential cross sections. The folded differential cross sections of both reactions show a similar behavior at all measured beam momenta, characterized by a prominent peak at cos=1. The cross section -+ shows a smooth but rapidly decreasing behavior as the beam momentum increases up to 550 MeV/c, whereas -+ shows a smooth and flat momentum dependence. These results are compared with some theoretical calculations based on nonrelativistic quark models. Although the shape of the folded differential cross section of the p»p-+ reaction is rather well reproduced by these models, that of the p»pK-K+ reaction, and, in particular, the prominent peak at cos=1 cannot be explained at all. The information from other experiments indicates that this discrepancy is most pronounced at the backward angles. Moreover, the momentum dependence of both -+ and -+ is not satisfactorily reproduced by these models.