V.I. Zhaba. 
Approximation of scattering phases for Reid93 potential. e-print arXiv:nucl-th/1811.00279
 
Abstract: 

For a single-channel nucleon-nucleon scattering, a well-known and convenient variable phase approach is considered, which is widely used for practical problems of atomic and nuclear physics. Approximation of the pp- and np- scattering phases obtained for the modern realistic phenomenological nucleon-nucleon potential Reid93 was carried out. The approximation function is used as a well-known formula for a parabolic-type quadratic function. 

Keywords: variable phase approach, nucleon-nucleon scattering, nucleon-
nucleon state, phase shifts, potential Reid93.