Precision measurement of the hadronic cross-section through the radiative return method

Abstract

Electron--positron annihilation into hadrons plus an energetic photon from initial-state radiation allows the hadronic cross-section to be measured over a wide range of energies at high luminosity meson factories. Weighted integrals over this cross-section are a decisive input for electroweak precision tests. A Monte Carlo event generator called PHOKHARA has been developed, which simulates $e^{+}{e}^{-}\to$ hadrons + photon(s) at the NLO accuracy. The latest tests and upgrades are presented in this paper.

Comments: Talk given at 7th International Workshop on Tau Lepton Physics (TAU 02), Santa Cruz, California, 10-13 Sep 2002. TAU-2002-WE06. 10 pages, 12 figures