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arXiv · hep-ph/0210014

Axial amplitudes for Delta excitation in chiral quark models

B. Golli·S. Sirca·L. Amoreira·M. Fiolhais
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Abstract

We study the axial amplitudes for the N-Delta transition in models with quarks and chiral mesons. A set of constraints on the pion field is imposed which enforces PCAC and the off-diagonal Goldberger-Treiman relation. The quark contribution to the amplitudes in general strongly underestimates the C^A_5 amplitude as well as the piNDelta strong coupling constant. We show that the results are considerably improved in models that, in addition to the pion cloud, incorporate a fluctuating sigma field inside the baryon.

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B. Golli, S. Sirca, L. Amoreira, M. Fiolhais. 2002-11-14. Axial amplitudes for Delta excitation in chiral quark models. https://doi.org/10.1016/s0370-2693(02)03192-1

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