Abstract
We report results from studies of baryon ground and resonant states by taking explicit mesonic degrees of freedom into account. We are following a relativistic coupled-channels approach relying on a Poincaré-invariant mass operator in matrix form. Generally, it corresponds to a bare particle that is coupled to a number of further mesonic channels. Here we present results, where the bare particle is either a bare nucleon or a bare Delta coupled to pion–nucleon and pion–Delta channels, respectively. For the pion–baryon vertices we employ coupling constants and form factors from different models in the literature. From the mass-operator eigenvalue equation we obtain the pion-dressing effects on the nucleon mass as well as the mass and pion-decay width of the Delta. The dressed masses become smaller than the bare ones, and a finite width of the Delta is naturally generated. The results are relevant for the construction of constituent-quark models for baryons, which have so far not included explicit mesonic degrees of freedom, but have rather relied on three-quark configurations only.
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References
T. Melde, W. Plessas, R.F. Wagenbrunn, Covariant calculation of mesonic baryon decays. Phys. Rev. C 72, 015207 (2005); ibid. C 74, 069901 (2006)
T. Melde, W. Plessas, B. Sengl, Covariant calculation of nonstrange decays of strange baryon resonances. Phys. Rev. C 76, 025204 (2007)
B. Sengl, T. Melde, W. Plessas, Covariant calculation of strange decays of baryon resonances. Phys. Rev. D 76, 054008 (2007)
T. Melde, W. Plessas, B. Sengl, Quark-model identification of baryon ground and resonant states. Phys. Rev. D 77, 114002 (2008)
T. Melde, L. Canton, W. Plessas, Structure of meson-baryon interaction vertices. Phys. Rev. Lett. 102, 132002 (2009)
H. Polinder, T.A. Rijken, Soft-core meson-baryon interactions. I. One-hadron-exchange potentials. Phys. Rev. C 72, 065210; Soft-core meson-baryon interactions. II. \(\pi N\) and \(K^+ N\) scattering, ibid. 065211 (2005)
L.Y. Glozman, W. Plessas, K. Varga, R.F. Wagenbrunn, Unified description of light and strange baryon spectra. Phys. Rev. D 58, 094030 (1998)
T. Sato, T.S.H. Lee, Meson exchange model for \(\pi N\) scattering and \(\gamma N \rightarrow \pi N\) reaction. Phys. Rev. C 54, 2660 (1996)
Acknowledgements
Open access funding provided by Austrian Science Fund (FWF). This work was supported by the Austrian Science Fund, FWF, through the Doctoral Program on Hadrons in Vacuum, Nuclei, and Stars (FWF DK W1203-N16).
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This article belongs to the Topical Collection “The 23rd European Conference on Few-Body Problems in Physics”.
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Schmidt, R.A., Canton, L., Plessas, W. et al. Baryon Masses and Hadronic Decay Widths with Explicit Pionic Contributions. Few-Body Syst 58, 34 (2017). https://doi.org/10.1007/s00601-016-1195-9
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DOI: https://doi.org/10.1007/s00601-016-1195-9