$\pi^0$ photoproduction on the proton for photon energies from 0.675 to 2.875 GeV

M. Dugger; B. G. Ritchie; J. P. Ball; P. Collins; E. Pasyuk; R. A. Arndt; W. J. Briscoe; I. I. Strakovsky; R. L. Workman; CLAS Collaboration

doi:10.1103/physrevc.76.025211

arXiv · 0705.0816

$\pi^0$ photoproduction on the proton for photon energies from 0.675 to 2.875 GeV

M. Dugger·B. G. Ritchie·J. P. Ball·P. Collins·E. Pasyuk·R. A. Arndt·W. J. Briscoe·I. I. Strakovsky·R. L. Workman·CLAS Collaboration

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Abstract

Differential cross sections for the reaction $\gamma p \to p \pi^0$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.675 to 2.875 GeV. The results reported here possess greater accuracy in the absolute normalization than previous measurements. They disagree with recent CB-ELSA measurements for the process at forward scattering angles. Agreement with the SAID and MAID fits is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been extended to 3 GeV. Resonance couplings have been extracted and compared to previous determinations.

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M. Dugger, B. G. Ritchie, J. P. Ball, P. Collins, E. Pasyuk, R. A. Arndt, W. J. Briscoe, I. I. Strakovsky, R. L. Workman, CLAS Collaboration. 2007-05-06. $\pi^0$ photoproduction on the proton for photon energies from 0.675 to 2.875 GeV. https://doi.org/10.1103/physrevc.76.025211

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