A Dynamical Model for the Resonant Multipoles and the $Δ$ Structure

S. S. Kamalov; S. N. Yang

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A Dynamical Model for the Resonant Multipoles and the $Δ$ Structure

S. S. Kamalov·S. N. Yang

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Abstract

We show that recent experiment data for the ratios $E_{1^+}/M_{1^+}$ and $S_{1^+}/M_{1^+}$ can be explained in a dynamical model for electromagnetic production of pions, together with a simple scaling assumption for the bare $γ^* N Δ$ form factors. Within our model we find that the bare $Δ$ is almost spherical and the electric E2 and Coulomb C2 quadrupole excitations of the physical $Δ$ are nearly saturated by pion cloud contribution in $Q^2 \le 4.0 GeV^2$.

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S. S. Kamalov, S. N. Yang. 2000-05-04. A Dynamical Model for the Resonant Multipoles and the $Δ$ Structure. https://arxiv.org/abs/nucl-th/0005007

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