Shape Coexistence at the 40 Sub-Shell Closures

International audienceShape coexistence at the Z=40 and/or N=40 are examples of interplay between macroscopical andmicroscopical effects in nuclear matter leading to the competition between spherical normal stateand intruder deformed configurations. How the nuclei change drastically its shape when adding orremoving 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 newavenues in the study of shape coexistence. In this presentation, the systematic study of shapecoexistence in neutron deficient Se and Kr isotopes, neutron rich Sr and Zr and neutron rich Fe andNi isotopes below 68Ni will be discussed from both experimental and theoretical perspectives