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arXiv · hep-ph/9902319

Two-Pion Exchange Interaction Between Constituent Quarks

D. O. Riska·G. E. Brown
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Abstract

The two-pion exchange interaction between constituent quarks is shown to enhance the effect of the the isospin dependent spin-spin component of the one-pion exchange interaction, and to cancel out its tensor component. It therefore provides a partial explanation for the phenomenological observation that the hyperfine interaction between constituent quarks is well described by a flavor dependent spin-spin interaction, which is attractive at short and repulsive at long range. The spin-orbit component of the two-pion exchange interaction is stronger than and has the opposite sign from that associated with the linear confining interaction in the $P-$shell multiplets.

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D. O. Riska, G. E. Brown. 1999-05-11. Two-Pion Exchange Interaction Between Constituent Quarks. https://doi.org/10.1016/s0375-9474(99)00260-2

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