Nucleon-nucleon potentials from Delta-full chiral effective-field-theory and implications

Understand

We closely investigate NN potentials based upon the Delta-full version of chiral effective field theory.

• We find that recently constructed NN potentials of this kind, which (when applied together with three-nucleon forces) were presented as predicting accurate binding energies and radii for a range of nuclei from A=16 to A=132 and providing accurate equations of state for nuclear matter, yield a chi^2/datum of 60 for the reproduction of the pp data below 100 MeV laboratory energy.
• This chi^2 is more than three times what the Hamada-Johnston potential of the year of 1962 achieved already some 60 years ago.
• We perceive this historical fact as concerning in view of the current emphasis on precision.