The Low energy structure of the Nucleon-Nucleon interaction: Statistical vs Systematic Uncertainties

We analyze the low energy NN interaction by confronting statistical vs systematic uncertainties. This is carried out with the help of model potentials fitted to the Granada-2013 database where a statistically meaningful partial wave analysis comprising a total of $6713$ np and pp published scattering data from 1950 till 2013 below $350\mathrm{M}\mathrm{e}\mathrm{V}$ has been made. We extract threshold parameters uncertainties from the coupled channel effective range expansion up to $j\le 5$. We find that for threshold parameters systematic uncertainties are generally at least an order of magnitude larger than statistical uncertainties. Similar results are found for np phase-shifts and amplitude parameters.