Séminaire DRS/Phys. Nucl - Piet van Isacker (GANIL) "Symmetries of the nuclear shell model"

mardi 6 sept. 2016, 10:25 → 11:25 Europe/Paris

bat 27

Ever since the pioneering studies by Wigner, Racah and Elliott, symmetry considerations have played a pivotal role in the development of nuclear models, in particular of the spherical shell model. Two types of interaction between the nucleons exist that allow an analytic solution of the nuclear many-body problem, namely the pairing and quadrupole interactions, giving rise to underlying SU(2) and SU(3) symmetries, respectively. In this talk the use of symmetry techniques in studies of exotic nuclei is illustrated with some examples. Particular attention is paid to properties related to the seniority quantum number, such as seniority isomers in semi-magic nuclei, and predictions for one-nucleon transfer and gamma decay. The role of higher-order terms in the hamiltonian and transition operators is also discussed.