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Nucleon mass and pion loops

M. B. Hecht·M. Oettel·C. D. Roberts·S. M. Schmidt·P. C. Tandy·A. W. Thomas
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Abstract

Poincare' covariant Faddeev equations for the nucleon and Delta are solved to illustrate that an internally consistent description in terms of confined-quark and nonpointlike confined-diquark-correlations can be obtained. pi N-loop induced self-energy corrections to the nucleon's mass are analysed and shown to be independent of whether a pseudoscalar or pseudovector coupling is used. Phenomenological constraints suggest that this self-energy correction reduces the nucleon's mass by up to several hundred MeV. That effect does not qualitatively alter the picture, suggested by the Faddeev equation, that baryons are quark-diquark composites. However, neglecting the pi-loops leads to a quantitative overestimate of the nucleon's axial-vector diquark component.

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M. B. Hecht, M. Oettel, C. D. Roberts, S. M. Schmidt, P. C. Tandy, A. W. Thomas. 2002-01-30. Nucleon mass and pion loops. https://doi.org/10.1103/physrevc.65.055204

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