ENERGY CORRELATIONS IN ELECTRON-POSITRON ANNIHILATION IN QUANTUM CHROMODYNAMICS - ASYMPTOTICALLY FREE PERTURBATION-THEORY

In the absence of infrared mass singularities, the asymptotic behavior of cross sections for e+e- annihilation in quantum chromodynamics can be expressed entirely in terms of the energy dependence of the renormalization-group running coupling constant. Since the theory is asymptotically free, the running coupling vanishes at high energy, and such infrared-finite cross sections can be calculated perturbatively. We extend previous work by calculating, through second order, the energy-weighted angular correlations of the hadrons produced in e+e- annihilation. This involves the computation of quark-antiquark-gluon production and the correction to the lowest-order quark-antiquark production from virtual gluon exchange. A dimensional-continuation scheme is employed to establish that these correlations, taken in a distribution-theory sense, are indeed free of mass singularities. The correlations exhibit interesting features which vanish slowly (1lnW) as the energy W increases. We estimate that the nonperturbative, confinement contributions to these features vanish much more rapidly (1W2). Thus, effects characteristic of quantum chromodynamics should be quite evident at high energies. © 1979 The American Physical Society.