Detailed quantum-chromodynamic predictions for high-pTprocesses

Abstract

High-${p}_{T}$ single-particle inclusive cross section calculations are presented for the CERN ISR and ISABELLE energy ranges, taking into account all lowest-order hard-scattering subprocesses required by quantum chromodynamics (QCD). The input quark and gluon distribution and fragmentation functions were determined from analyses of deep-inelastic lepton data and were subject to various theoretical constraints such as sum rules and SU(3) symmetry. We thoroughly discuss the effects of the individual contributions from fermionic and gluonic subprocesses, as well as those effects stemming from QCD scaling violations in parton distributions and/or fragmentation functions. In particular, the inclusion of the large elastic gluon-gluon and gluon-quark scattering terms has a profound effect on both the normalization and the ${p}_{T}$ dependence of the predictions. The ${p}_{T}$ and $\ensuremath{\theta}$ dependences of single-${\ensuremath{\pi}}^{0}$ production are shown to be in good agreement with available data in the region ${p}_{T}\ensuremath{\gtrsim}4.5$ GeV/c and $\sqrt{s}\ensuremath{\gtrsim}50$ GeV. In addition, we predict and discuss various ratios for inclusive single-particle production of ${\ensuremath{\pi}}^{+}$, ${\ensuremath{\pi}}^{\ensuremath{-}}$, ${K}^{+}$, and ${K}^{\ensuremath{-}}$, which also turn out to be in excellent agreement with presently available experiments.