New Analysis of Threshold Photoproduction Data from MAMI

Abstract

In this talk I will review the recently published results by the A2 and CB-TAPS Collaborations at MAMI on neutral pion photoproduction in the near-threshold region. The combined measurement of the differential cross section and the photon beam asymmetry with low statistical errors allowed for a precise determination of the energy dependence of the real parts of the S- and P-wave amplitudes for the first time, providing the most stringent test to date of the predictions of Chiral Perturbation Theory and its energy region of agreement with experiment.