Production Rates and Distinctive Components of Single-Particle Distributions

Abstract

The production mechanism of a particle in multi-particle production is distinguished according to whether it is composed of urbaryons coming partly from incident particles, or is composed only of ones newly created in the collision. The former mechanism, which is different for a particle and its antiparticle, gives constant multiplicity and rapid limiting behaviour in the fragmentation region. In the case of pp collisions, the limiting energy for this mechanism is somewhat above 10 Ge VI c. The latter mechanism gives the same increasing multiplicity and distribution for a particle and its antiparticle. The scaling energy in the latter mechanism including x-0 is quite different for rr, K and p, indicating strong mass dependence. The scaling energies in the reactions pp-7rr-X, K-X and pX are around 30 GeVIc, a few hundred GeVIc and 1 TeVIc, respectively. It is conjectured that the average multiplicity differences such as nn•-nn-, riK•-nKbecome energy independent at energies somewhat above 10 Ge VIc for pp and K+p collisions. a) Typical diagrams for baryon<a>+baryon<b>-7baryon<•>+X. b) Typical diagrams for antibaryon<a>+baryon<b>-7baryon<•>+X, not appearing in a).

Rank Structure of Exclusive Reactions and Characteristic Features of Inclusive Spectra

“…It is to be noted here that the concepts of limiting and scaling behaviour should be distinguished, corresponding to the categories II and III of the production mechanism, respectively. 15 > The limiting behaviour in the region x>O or x<O, i.e., projectile or target fragmentation region, is attributed to the H®P types (II a or II b), respectively, the H®H types give non-limiting contributions vanishing as energy increases.…”

“…For simplicity, we confine ourselves to the inclusive reactions a+ b~c +X with c=/=a, b, i.e., v =II or III. Then we have the following equations in terms of the reduction rule 6 >: s *> It is important to distinguish the production mechanism of particle c according to whether it is composed of urbaryons all coming from one of the incident particles a and b (the category I), partly coming from one or both of them (the category II), or it is composed only from ones newly reated in the collision (the category 111).14), 15) The four types of reduced diagrams are shown in Fig. 4.…”