Pion photoproduction in the Δ resonance region

Abstract

We have updated our multipole analyses to incorporate new data from the low-energy and $\ensuremath{\Delta}$ resonance regions. We note a slight decrease in our estimate of the $\ensuremath{\Delta}$ photodecay amplitudes. This agrees with results found in Compton scattering. Our values are also in good agreement with another previous determination. We have reexamined our determinations of the $E2/M1$ ratio at the resonance energy and at the pole. We find an $E2/M1$ ratio (at the pole) which is in good agreement with the recent Mainz value.