Eur. Phys. J. A (2009) 41: 71-84
https://doi.org/10.1140/epja/i2009-10771-0

Regular Article - Theoretical Physics

Neutral pion photoproduction at high energies

¹ Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) und Bethe Center for Theoretical Physics, Universität Bonn, D-53115, Bonn, Germany
² Excited Baryon Analysis Center (EBAC), Thomas Jefferson National Accelerator Facility, 23606, Newport News, VA, USA
³ Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425, Jülich, Germany
⁴ Institute of Advanced Simulations, Forschungszentrum Jülich, D-52425, Jülich, Germany
⁵ Theory Center, Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., 23606, Newport News, VA, USA
⁶ College of William and Mary, Williamsburg, Williamsburg, 23187, VA, USA

^* e-mail: j.haidenbauer@fz-juelich.de

Received: 11 February 2009
Revised: 26 March 2009
Accepted: 30 March 2009
Published online: 6 May 2009

Abstract

A Regge model with absorptive corrections is employed in a global analysis of the world data on the reactions p p and n n for photon energies from 3 to 18GeV. In this region resonance contributions are expected to be negligible so that the available experimental information on differential cross-sections and single and double polarization observables at - t 2 GeV²allows us to determine the reaction amplitude reliably. The model amplitude is then used to predict observables for photon energies below 3GeV. A detailed comparison with recent data from the CLAS and CB-ELSA Collaborations in that energy region is presented. Furthermore, the prospects for determining the radiative decay width via the Primakoff effect from the reaction p p are explored.