ENERGY SENSITIVITY OF THE LOW-ENERGY PARAMETERS OF NEUTRON-PROTON SCATTERING FOR VARIOUS NUCLEON-NUCLEON POTENTIALS
The triplet and singlet low-energy parameters in the effective-range
expansion for neutron?proton scattering were determined with the
aid of the most popular modern realistic nucleon?nucleon potentials
(Nijm I), (Nijm II) and (Reid93). We compared our results with
the latest partial wave analysis experimental data from the SAID
nucleon?nucleon database and newest values at, as, rt and rs
parameters were presented. Our calculations based on these three
potentials at incident neutron energy less than 60 KeV show that
there are some discrepancies with experimental data. In order to
decrease the discrepancy between our results and the experimental
ones at very low energy, we suggest to include coupling terms
3S1 + 3D1 for constructing various realistic nuclear-force models.
Furthermore, the calculated effective range expansions in this work
are not very accurate for very low energy unless considering into
account many terms vn in the expansions.