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Analysis of the quadrupole deformation of $Δ$(1232) within an effective Lagrangian model for pion photoproduction from the nucleon

C. Fernandez-Ramirez·E. Moya de Guerra·J. M. Udias
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Abstract

We present an extraction of the E2/M1 ratio of the $Δ$(1232) from experimental data applying an effective Lagrangian model. We compare the result obtained with different nucleonic models and we reconcile the experimental results with the Lattice QCD calculations.

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C. Fernandez-Ramirez, E. Moya de Guerra, J. M. Udias. 2006-11-16. Analysis of the quadrupole deformation of $Δ$(1232) within an effective Lagrangian model for pion photoproduction from the nucleon. https://doi.org/10.1140/epja%2Fi2006-10198-1

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