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Comment on "Comparison of Potential Models with the PP Scattering Data Below 350 Mev"

G. Q. Li·R. Machleidt
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Abstract

We point out two flaws in the recent test of nucleon-nucleon (NN) potentials conducted by Stoks and de Swart. First, in some cases, the neutron-proton ($np$) version of an NN potential was compared to the proton-proton ($pp$) data, which is improper and yields (large) $χ^2$ that are essentially meaningless. Second, for a proper test of the quantitative nature of a NN potential, it is insufficient to compare to $pp$ data only, since this leaves the T=0 potential untested. Thus, it can happen that the $pp$ version of a potential predicts the $pp$ data accurately, while the $np$ version of that same potential is poor in $np$ (where also the T=0 potential is involved). An example for this is the Nijmegen potential, which predicts the $pp$ data well with a $χ^2$/datum of 2.0, but yields a $χ^2$/datum of 6.5 in $np$.

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G. Q. Li, R. Machleidt. 1993-04-27. Comment on "Comparison of Potential Models with the PP Scattering Data Below 350 Mev". https://arxiv.org/abs/nucl-th/9304022

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