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Dynamical Diquarks and Baryon Transition Form Factors

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Abstract

The role and impact of dynamical diquark correlations that appear within three-quark bound states (baryons), owing largely to the mechanisms responsible for the emergence of hadron masses, can be addressed via the computation of baryon electromagnetic transition form factors (TFFs). Herein, we describe a procedure based upon continuum Schwinger methods to evaluate such physical objects. For illustration purposes, we specialize on the \(\gamma ^{(*)}p \rightarrow N(1535)\frac{1}{2}^-\) TFF, in which the interference between the different diquark correlations plays a determining role. Albeit limited to a symmetry-preserving treatment of a vector \(\otimes \) vector contact-interaction model of quantum chromodynamics, both the mathematical procedure and numerical results serve as benchmarks for more sophisticated calculations to be developed in the future.

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Notes

  1. The smallest value of \(m_H\) corresponds to the ground-state.

  2. If flavor symmetry is not assumed, one need to take the individual contributions of each quark flavor, weighted by the corresponding electric charges.

  3. The Dirac and Pauli form factors can be recast in terms of the electric (\(G_E\)) and magnetic (\(G_M\)) Sach form factors  [44].

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Acknowledgements

This work has been partially funded by Ministerio Español de Ciencia e Innovación under grant No. PID2019-107844GB-C22; and Junta de Andalucía under contract Nos. Operativo FEDER Andalucía 2014-2020 UHU-1264517, P18-FR-5057 and also PAIDI FQM-370.

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  1. Dpto. Ciencias Integradas, Centro de Estudios Avanzados en Fis., Mat. y Comp., Fac. Ciencias Experimentales, Universidad de Huelva, 21071, Huelva, Spain

    Khépani Raya

  2. Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, 41013, Sevilla, Spain

    Jorge Segovia

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Raya, K., Segovia, J. Dynamical Diquarks and Baryon Transition Form Factors. Few-Body Syst 64, 78 (2023). https://doi.org/10.1007/s00601-023-01858-1

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