Structure of the nucleon and its first radial excitation

Abstract

A Poincaré-covariant continuum approach to the three valence-quark bound-state problem in quantum field theory is used to perform a detailed analysis of the nucleon's ground and first excited states: the so-called $N(940){\frac{1}{2}}^{+}$ and $N(1440){\frac{1}{2}}^{+}$. Such analysis predicts the presence of nonpointlike, fully-interacting quark-quark (diquark) correlations within them, being the isoscalar-scalar and isovector-pseudovector diquarks overwhelmingly dominant with similar relative strengths in both states. Moreover, the rest-frame wave functions of both states are largely $S$-wave in nature and the first excited state in this $1/2^{+}$ channel has the appearance of a radial excitation of the ground state. All these features have numerous observable consequences, we show herein those related with the nucleon's elastic, Roper's elastic and nucleon-to-Roper transition electromagnetic form factors, for both charged and neutral channels.

arXiv comment16 pages, 7 figures, Contribution to a Special Issue of Few-Body Systems, dedicated to Ludwig Faddeev

References in corpus (9)

• Electroexcitation of nucleon resonances
• Pseudoscalar Meson Radial Excitations
• Octet and Decuplet Baryons in a Covariant and Confining Diquark-Quark Model
• Pion-nucleon scattering in a meson-exchange model
• Electroproduction of nucleon resonances
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Cited by in corpus (3)

• Spectrum of light- and heavy-baryons
• Electromagnetic Transition Form Factors of Baryon Resonances
• Nucleon-to-Resonance Form Factors at Large Photon Virtualities