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arXiv · hep-ph/9910272

Meson-like Baryons and the Spin-Orbit Puzzle

Nathan Isgur
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Abstract

I describe a special class of meson-like Λ_Q excited states and present evidence supporting the similarity of their spin-independent spectra to those of mesons. I then examine spin-dependent forces in these baryons, showing that predicted effects of spin-orbit forces are small for them for the same reason they are small for the analogous mesons: a fortuitous cancellation between large spin-orbit forces due to one-gluon-exchange and equally large inverted spin-orbit forces due to Thomas precession in the confining potential. In addition to eliminating the baryon spin-orbit puzzle in these states, this solution provides a new perspective on spin-orbit forces in all baryons.

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Nathan Isgur. 1999-10-07. Meson-like Baryons and the Spin-Orbit Puzzle. https://doi.org/10.1103/physrevd.62.014025

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