Inclusive particle production in pp interactions at 12 and 24 GeV/c I The central region

The authors present double-differential cross sections for the central region in the reactions p+p to pi /sup +or-/+anything at incident laboratory momenta of 12 and 24 GeV/c, and compare them with CERN-ISR measurements at higher momenta. They find remarkable regularities when they express these cross sections as functions of y*, p/sub T/, and s. The use of the c.m. longitudinal rapidity y*=sinh/sup -1/(p*/sub ////(p/sup 2//sub T/+m/sup 2/)/sup 1/2/) (where p*/sub /// and p/sub T / are the longitudinal and transverse c.m. momenta), instead of the more conventional variable x=p*/sub ////( square root s/2), is crucial because these regularities in the central region are not evident in the variables x and p/sub T/. (12 refs).