Résumé du preprint Irfu-15-14

Neutron-driven collectivity in light tin isotopes: Proton inelastic scattering from 104Sn
A. Corsi, S. Boissinot, A. Obertelli, P. Doornenbal, M. Dupuis, F. Lechaftois, M. Matsushita, S. Péru, S. Takeuchi, H. Wang, N. Aoi , H. Baba, P. Bednarczyk, M. Ciemala, A. Gillibert, T. Isobe, A. Jungclaus, V. Lapoux, J. Lee, M. Martini, K. Matsui, T. Motobayashi, D. Nishimura, S. Ota, E. Pollacco , H. Sakurai, C. Santamaria, Y. Shiga, D. Sohler, D. Steppenbeck, R. Taniuchi
IRFU-15-14 Inelastic scattering cross sections to individual bound excited states of 104Sn were measured at 150MeV/u beam energy and analyzed to evaluate the contribution of neutron and proton collectivity. State-of-the-art Quasi-Particle Random Phase Approximation (QRPA) with the D1M Gogny interaction reproduces the experimental proton collectivity and our inelastic scattering cross sections once used as input for a reaction calculation together with the JeukenneLejeuneMahaux (JLM) potentials. Experimental inelastic scattering cross section decreases by 40(24)% from 112Sn to 104Sn. The present work shows that (i) proton and neutron collectivities are proportional over a large range of tin isotopes (including 104Sn), as is typical for isoscalar excitations, and (ii) the neutron collectivity dominates. It suggests that the plateau in the mass range A =106112displayed by E2 transition probabilities is driven by neutron collectivity.