Shape Coexistence at the 40 Sub-Shell Closures

Abstract : Shape coexistence at the Z=40 and/or N=40 are examples of interplay between macroscopical and microscopical effects in nuclear matter leading to the competition between spherical normal state and intruder deformed configurations. How the nuclei change drastically its shape when adding or removing one or two pairs of nucleon remains an open subject in nuclear structure. Experimentally, the development of radioactive beams facilities and state of the art detections systems opened new avenues in the study of shape coexistence. In this presentation, the systematic study of shape coexistence in neutron deficient Se and Kr isotopes, neutron rich Sr and Zr and neutron rich Fe and Ni isotopes below 68Ni will be discussed from both experimental and theoretical perspectives.