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arXiv · hep-ex/0311045

Photoproduction of eta mesons off protons for photon energies from 0.75 GeV to 3 GeV

Volker Crede·Olivia Bartholomy
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Abstract

Total and differential cross sections for the reaction p(gamma, eta)p have been measured for photon energies in the range from 750 MeV to 3 GeV. The low-energy data are dominated by the S11 wave which has two poles in the energy region below 2 GeV. Eleven nucleon resonances are observed in their decay into p eta. At medium energies we find evidence for a new resonance N(2070)D15 with (mass, width) = (2068+-22, 295+-40) MeV. At photon energies above 1.5 GeV, a strong peak in forward direction develops, signalling the exchange of vector mesons in the t channel.

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Volker Crede, Olivia Bartholomy. 2004-10-20. Photoproduction of eta mesons off protons for photon energies from 0.75 GeV to 3 GeV. https://doi.org/10.1103/physrevlett.94.012004

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