An inclusive approach to scanning $e^+e^-\to \pi^+\pi^-$ cross section below $1$ GeV by the radiative-return method

An inclusive approach to measuring $e^+e^-\to \pi^+\pi^-$ cross section by the radiative-return method is discussed. This approach is substantially based on the choice of selection rules that exclude three-pion events and reduce the radiation background in the final state. Radiative corrections in the process with emission in the initial state are calculated for the DAPHNE conditions by treating the cross section form and the kinematics of the radiative process in the quasi-real electron approximation.