Photoproduction of neutral pions off protons

Abstract

Photoproduction of neutral pions has been studied with the CBELSA/TAPS detector in the reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}p{\ensuremath{\pi}}^{0}$ for photon energies between 0.85 and 2.50 GeV. The ${\ensuremath{\pi}}^{0}$ mesons are observed in their dominant neutral decay mode: ${\ensuremath{\pi}}^{0}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}$. For the first time, the differential cross sections cover the very forward region, ${\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}<{60}^{\ensuremath{\circ}}$. A partial-wave analysis of these data within the Bonn-Gatchina framework observes the high-mass resonances ${G}_{17}$(2190), ${D}_{13}$(2080), and ${D}_{15}$(2070).