Higher-order corrections to jet cross sections in e+e- annihilation.

TLDR: A general method to calculate next-to-leading order multijet cross sections is presented, with the emphasis on how to isolate the soft and collinear divergences in multiparton matrix elements.

Abstract: A general method to calculate next-to-leading order multijet cross sections is presented. The emphasis is on how to isolate the soft and collinear divergences in multiparton matrix elements. As an example, the method is used to isolate the divergences at leading order in the number of colours in the processes e+e- + qQ + n gluons and e+e- -t qcjqQ + n gluons. The usual algebraic complexity of calculating next-to-leading order corrections in QCD is avoided, especially the d-dimensional squaring of the real matrix elements and the hard phase space integrals. Some remarks about the stucture of the virtual contributions are made. As a first application, and to examine the feasibility of the approach, explicit Monte Carlo programs are constructed which contain the next-to-leading order corrections to e+e- -+ 2 jets and e+e- + 3 jets. It is demonstrated that the method works and can be readily applied to a variety of processes.