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arXiv · 1306.3864

Electromagnetic structure of the nucleon and the Roper resonance in a light-front quark approach

Igor T. Obukhovsky·Amand Faessler·Thomas Gutsche·Valery E. Lyubovitskij
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Abstract

A relativistic light-front quark model is used to describe both the elastic nucleon and nucleon-Roper transition form factors in a large Q2 range, up to 35 GeV2 for the elastic and up to 12 GeV2 for the resonance case. Relativistic three-quark configurations satisfying the Pauli exclusion principle on the light-front are used for the derivation of the current matrix elements. The Roper resonance is considered as a mixed state of a three-quark core configuration and a molecular N+sigma hadron component. Based on this ansatz we obtain a realistic description of both processes, elastic and inelastic, and show that existing experimental data are indicative of a composite structure of the Roper resonance.

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Igor T. Obukhovsky, Amand Faessler, Thomas Gutsche, Valery E. Lyubovitskij. 2013-06-17. Electromagnetic structure of the nucleon and the Roper resonance in a light-front quark approach. https://doi.org/10.1103/physrevd.89.014032

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