Radiative return via electron pair production: Monte Carlo simulation of   the process e+ e- --> pi+ pi- e+ e-
  Contributions from the reaction e+e- --> pi+pi- e+e- to the pion form factor measurement via radiative return method are discussed basing on the results of a Monte Carlo generator (EKHARA). The generator contains contributions from the initial and final state emission of a e+e- pair from e+e- --> pi+pi- production diagrams and the pi+pi- pair production from space-like and time-like Bhabha diagrams. A detailed study is performed for the Phi- factory energy. Tests of the generation procedure are also presented. 
Henryk Czyz, Elzbieta Nowak-Kubat