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On the structure of large N cancellations in baryon chiral perturbation theory

Ruben Flores-Mendieta·Christoph P. Hofmann·Elizabeth Jenkins·Aneesh V. Manohar
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Abstract

We show how to compute loop graphs in heavy baryon chiral perturbation theory including the full functional dependence on the ratio of the Delta--nucleon mass difference to the pion mass, while at the same time automatically incorporating the 1/N cancellations that follow from the large-N spin-flavor symmetry of baryons in QCD. The one-loop renormalization of the baryon axial vector current is studied to demonstrate the procedure. A new cancellation is identified in the one-loop contribution to the baryon axial vector current. We show that loop corrections to the axial vector currents are exceptionally sensitive to deviations of the ratios of baryon-pion axial couplings from SU(6) values.

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Ruben Flores-Mendieta, Christoph P. Hofmann, Elizabeth Jenkins, Aneesh V. Manohar. 2000-01-20. On the structure of large N cancellations in baryon chiral perturbation theory. https://doi.org/10.1103/physrevd.62.034001

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