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arXiv · 1606.00592

Precise Determination of Charge Dependent Pion-Nucleon-Nucleon Coupling Constants

R. Navarro Perez·J. E. Amaro·E. Ruiz Arriola
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Abstract

We undertake a covariance error analysis of the pion-nucleon-nucleon coupling constants from the Granada-2013 np and pp database comprising a total of 6720 scattering data below LAB energy of 350 MeV. Assuming a unique pion-nucleon coupling constant in the One Pion Exchange potential above a boundary radius $r_c=3 {\rm fm}$ we obtain $f^2=0.0763(1)$. The effects of charge symmetry breaking on the $^3P_0$, $^3P_1$ and $^3P_2$ partial waves are analyzed and we find $f_{p}^2 = 0.0761(4)$, $f_{0}^2 = 0.0790(9)$ and $f_{c}^2 = 0.0772(6)$ with a strong anti-correlation between $f_c^2$ and $f_0^2$. We successfully test normality for the residuals of the fit. Potential tails in terms of different boundary radii as well as chiral Two-Pion-Exchange contributions as sources of systematic uncertainty are also investigated.

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R. Navarro Perez, J. E. Amaro, E. Ruiz Arriola. 2017-05-18. Precise Determination of Charge Dependent Pion-Nucleon-Nucleon Coupling Constants. https://doi.org/10.1103/physrevc.95.064001

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