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Double neutral pion photoproduction at threshold

V. Bernard·N. Kaiser·Ulf-G. Meißner
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Abstract

We consider the chiral expansion of the threshold amplitude for the reaction $γp \to π^0 π^0 p$ to order ${\cal O}(M_π^2)$. We substantiate a claim that this photoproduction channel is significantly enhanced close to threshold due to pion loops. A precise measurement of the corresponding cross sections is called for which allows to test chiral perturbation theory.

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V. Bernard, N. Kaiser, Ulf-G. Meißner. 1996-04-09. Double neutral pion photoproduction at threshold. https://doi.org/10.1016/0370-2693(96)00646-6

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