Inelastic electron-pion scattering at FNAL (SELEX)

Abstract

In this report we describe the analysis status of electron-pion inelastic scattering $\pi e \to \pi' e' \gamma$ and $\pi e \to \pi' e' \pi^0$ reaction data, measured in inverse pion-electron scattering at 590 GeV/c at FNAL. The data give information on reactions that were never previously measured: (1) $\pi e \to \rho e'$ scattering for a determination of the $\rho \to \pi \gamma$ radiative width from a measurement of the transition form factor near zero momentum transfer, (2) $ \pi e \to e' \pi' \pi^0$ scattering near threshold for a determination of the chiral anomaly transition form factor and the $\gamma \to 3 \pi$ F$_{3\pi}$ chiral anomaly amplitude, and (3) $\pi e \to \pi' e' \gamma $ scattering, in which a virtual photon from the electron's Coulomb field is Compton scattered on the pion, for a determination of the never previously measured generalized pion polarizabilities.