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arXiv · 1908.11816

Constraints from a large-N_c analysis on meson-baryon interactions at chiral order Q^3

Abstract

We consider the chiral Lagrangian for baryon fields with J^P =\frac{1}{2}^+ or J^P =\frac{3}{2}^+ quantum numbers as constructed from QCD with up, down and strange quarks. The specific class of counter terms that are of chiral order Q^3 and contribute to meson-baryon interactions at the two-body level is constructed. Altogether we find 24 terms. In order to pave the way for realistic applications we establish a set of 22 sum rules for the low-energy constants as they are implied by QCD in the large-N_c limit. Given such a constraint there remain only 2 independent unknown parameters that need to be determined by either Lattice QCD simulations or directly from experimental cross section measurements. At subleading order we arrive at 5 parameters.

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Yonggoo Heo, C. Kobdaj, M. F. M. Lutz. 2019-08-30. Constraints from a large-N_c analysis on meson-baryon interactions at chiral order Q^3. https://doi.org/10.1103/physrevd.100.094035

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