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arXiv · 1101.4244

Masses of ground and excited-state hadrons

H. L. L. Roberts·L. Chang·I. C. Cloet·C. D. Roberts
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Abstract

We present the first Dyson-Schwinger equation calculation of the light hadron spectrum that simultaneously correlates the masses of meson and baryon ground- and excited-states within a single framework. At the core of our analysis is a symmetry-preserving treatment of a vector-vector contact interaction. In comparison with relevant quantities the root-mean-square-relative-error/degree-of freedom is 13%. Notable amongst our results is agreement between the computed baryon masses and the bare masses employed in modern dynamical coupled-channels models of pion-nucleon reactions. Our analysis provides insight into numerous aspects of baryon structure; e.g., relationships between the nucleon and Delta masses and those of the dressed-quark and diquark correlations they contain.

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H. L. L. Roberts, L. Chang, I. C. Cloet, C. D. Roberts. 2011-01-21. Masses of ground and excited-state hadrons. https://doi.org/10.1007/s00601-011-0225-x

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