Estimate of the pionic contribution to very forward electron scattering from He3 by surprisal analysis

Surprisal analysis is applied to the very forward electron scattering data on He3, for which the three-body theory fails to explain the excitation function. This discrepancy is often attributed to higher momentum components in the wave function of He3. An explicit expression for the final state densities including the nucleon and pion degrees of freedom is proposed. The present surprisal analysis succeeds in reproducing the experimental data without calling upon higher momentum components and suggests that even in the so-called quasielastic scattering region, not only nucleons but also a considerable number of pions are emitted in electron scattering.