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arXiv · 0902.1819

Neutral pion photoproduction at high energies

A. Sibirtsev·J. Haidenbauer·S. Krewald·U. -G. Meißner·A. W. Thomas
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Abstract

A Regge model with absorptive corrections is employed in a global analysis of the world data on the reactions gamma p -> pi0 p and gamma n -> pi0 n for photon energies from 3 to 18 GeV. 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 GeV^2 allows us to determine the non-resonant part of the reaction amplitude reliably. The model amplitude is then used to predict observables for photon energies below 3 GeV. 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 pi0 radiative decay width via the Primakoff effect from the reaction gamma p -> pi0 p are explored.

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A. Sibirtsev, J. Haidenbauer, S. Krewald, U. -G. Meißner, A. W. Thomas. 2009-03-31. Neutral pion photoproduction at high energies. https://doi.org/10.1140/epja/i2009-10771-0

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