Short-Range Contact Interaction Control of Nuclear Quadrupole Collectivity
In ab initio nuclear structure, the electric quadrupole moment of a deformed nucleus can be increased or decreased by the short-range S-wave nucleon-nucleon contact interaction, independently of the long-range physics that sets the nuclear shape. Two opposing contacts—a repulsive singlet and an attractive triplet S-wave term—compete by favoring polar versus equatorial surface oscillations of the dominant deformed shape, altering collectivity by up to about 50 percent without remixing shapes.
Unexpected Rise in Nuclear Collectivity from Short-Range Physics
Shows that quadrupole collectivity in light atomic nuclei—historically attributed to long-range deformation—is also governed by the short-range S-wave nucleon-nucleon contact interaction. Using the s…