Double Pion Photoproduction on the Proton up to 800 MeV

The total cross sections for the three γp → N ππ reactions have been measured for photon energies from 450 to 800 MeV. The γp → pπ0π0 and γp → nπ+π0 rcross sections have never been measured before while the γp → pπ+π− results are much improved compared to earlier data. These measurements were performed with the large acceptance hadronic detector DAPHNE, at the tagged photon beam facility of MAMI microtron in Mainz.