. . "model" . "liquid drop" . . "liquid-drop model" . . "liquid drop model" . "Bethe\u2013Weizs\u00E4cker formula" . "quantum liquid drop" . "pairing" . . . . "Weizs\u00E4cker formula" . "model not considering such effects" . "Pairing Effects" . "neutron pairing" . "models" . "model the nucleus as a drop of water" . "Semi-empirical mass formula" . "semi-empirical mass formula" . "nuclear pairing effects" . "forces that bind the neutron" . "nuclear liquid drop model" . . "Semi-empirical mass formula" . "pairing effects" . "semi-empirical formula" . . "Bethe\u2013Weizsacker mass formula" . . "Semi-empirical_mass_formula" . "pairing effect" .