Excitation Energy of Nuclei With Two Valance Nucleons Calculated Using The Shell Model with Modified Surface Delta Interaction

Abstract

The excitation energy of nuclear levels with the total angular momentum   and  in even- even nuclei containing two valance nucleons, either as particles outside the closed core or as holes within it, were calculated using the shell model with the modified surface delta interaction as a residual interaction between a two valence nucleons. The values of two interaction constants for each studied nucleus were determined separately using the least squares fitting method to ensure optimal agreement between theoretical calculations and available experimental data.

Comparison of the theoretically calculated values with the most recent available experimental data yielded a mean absolute deviation of MAD=0.283 MeV, which is in good agreement with previous studies that employed other effective interactions.

This agreement further confirms the validity of the shell model in describing excitation levels across a wide range of nuclei and demonstrates the ability of modified surface delta interaction to accurately calculate for the residual interaction among valance nucleons, as well as to reproduce the general trends of energy levels across different nuclei.