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arXiv · 1510.06266

Watson's theorem and the $NΔ(1232)$ axial transition

L. Alvarez-Ruso·E. Hernández·J. Nieves·M. J. Vicente Vacas
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Abstract

We present a new determination of the $NΔ$ axial form factors from neutrino induced pion production data. For this purpose, the model of Hernandez {\it et al.} [Phys. Rev. D76, 033005 (2007)] is improved by partially restoring unitarity. This is accomplished by imposing Watson's theorem on the dominant vector and axial multipoles. As a consequence, a larger $C_5^A(0)$, in good agreement with the prediction from the off-diagonal Goldberger-Treiman relation, is now obtained.

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L. Alvarez-Ruso, E. Hernández, J. Nieves, M. J. Vicente Vacas. 2016-01-18. Watson's theorem and the $NΔ(1232)$ axial transition. https://doi.org/10.1103/physrevd.93.014016

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