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The role of Delta(1700) excitation and rho production in double pion photoproduction

J. C. Nacher·E. Oset·M. J. Vicente Vacas·L. Roca
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Abstract

Recent information on invariant mass distributions of the $γp\toπ^+π^0 n$ reaction, where previous theoretical models had shown deficiencies, have made more evident the need for new mechanisms, so far neglected or inaccurately included. We have updated a previous model to include new necessary mechanisms. We find that the production of the $ρ$ meson, and the $Δ(1700)$ excitation, through interference with the dominant terms, are important mechanisms that solve the puzzle of the $γp\toπ^+π^0 n$ reaction without spoiling the early agreement with the $γp\toπ^+π^- p$ and $γp\toπ^0π^0 p$ reactions.

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J. C. Nacher, E. Oset, M. J. Vicente Vacas, L. Roca. 2001-05-24. The role of Delta(1700) excitation and rho production in double pion photoproduction. https://doi.org/10.1016/s0375-9474(01)01110-1

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