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Direct calculation of the K-matrix for pion electro-production in the Delta channel

P. Alberto·L. Amoreira·M. Fiolhais·B. Golli·S. Sirca
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Abstract

We present a method to calculate directly the K-matrices for the pion electro-production processes in the framework of chiral quark models which allows for a clean separation of the resonant amplitudes from the background. The method is applied to the calculation of the multipole amplitudes M_{1+}, E_{1+}, and S_{1+} in the Delta channel within the Cloudy Bag Model. A good overall description is found in a broad energy range.

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P. Alberto, L. Amoreira, M. Fiolhais, B. Golli, S. Sirca. 2005-10-03. Direct calculation of the K-matrix for pion electro-production in the Delta channel. https://doi.org/10.1140/epja%2Fi2005-10160-9

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