Structure of the Lightest Tin Isotopes

We link the structure of nuclei around Sn-100, the heaviest doubly magic nucleus with equal neutron and proton numbers (N = Z = 50), to nucleon-nucleon (NN) and three-nucleon (NNN) forces constrained by data of few-nucleon systems. Our results indicate that Sn-100 is doubly magic, and we predict its quadrupole collectivity. We present precise computations of Sn-101 based on three-particle- two-hole excitations of 100Sn, and we find that one interaction accurately reproduces the small splitting between the lowest J(pi) = 7/2(+) and 5/2(+) states.