Quadrupole collectivity in silicon isotopes approaching neutron number N = 28
نویسندگان
چکیده
Quadrupole deformation parameters, |β2,(p,p′)|, have been deduced for 36,38,40Si from measured inelastic proton-scattering cross sections. Due to the strong Z = 14 subshell gap, low-lying quadrupole collectivity in these nuclei is attributed to the excitation of valence neutrons. Enhanced collectivity at N = 26 indicates a reduced N = 28 shell gap at large neutron excess in this chain of isotopes. Data are compared to large-scale shell-model calculations and prior Coulomb excitation measurements on 36,38Si. © 2007 Elsevier B.V. All rights reserved. PACS: 25.40.Ep; 21.10.Re; 27.30.+z; 27.40.+z
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