The NNLO tau+tau- Production Cross Section Close to Threshold
arXiv:hep-ph/0103259 · doi:10.1103/PhysRevD.64.053001
Abstract
The threshold behaviour of the cross section sigma(e+e+ -> tau+tau-) is analysed, taking into account the known higher-order corrections. At present, this observable can be determined to next-to-next-to-leading order (NNLO) in a combined expansion in powers of alpha_s and fermion velocities.
23+1 pages, 6 figures