Higher-order QED corrections to e+e- to nu bar nu gamma at LEP2

Abstract

The process e+e- to nu barnu + gamma with a distinctive ``photon-plus-missing-energy'' signal can serve as an important tool to search for new physics at LEP2. It can be exploited to measure the WW gamma coupling, or to search for weakly interacting and invisible (s)particles. For meaningful comparisons of experimental data with theoretical predictions, higher-order QED corrections due to multiphoton emission must be taken into account. In the present paper we explain how the WW gamma coupling has been incorporated into the KORALZ Monte Carlo program, which can now be used for simulations of e+e- to nu bar nu + gamma events with higher-order QED corrections. The strategy of how to perform an experimental analysis in the presence of experimental cuts is proposed. The question of systematic uncertainties is addressed and some numerical results for the phenomenologically interesting case of anomalous WW gamma couplings are also given.