Quadrupole collectivity in silicon isotopes approaching neutron number N=28

doi:10.1016/j.physletb.2007.07.005

Physics Letters B

Volume 652, Issue 4, 30 August 2007, Pages 169-173

https://doi.org/10.1016/j.physletb.2007.07.005 Get rights and content

Abstract

Quadrupole deformation parameters, $| β_{2, (p, p^{'})} |$ , 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.

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Acknowledgements

This work was supported by the National Science Foundation under Grants No. PHY-0606007, PHY-9875122, PHY-0555366, PHY-0355129, INT-0089581 and by the Japan Society for the Promotion of Science.

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Quadrupole collectivity in silicon isotopes approaching neutron number N=28

Abstract

Section snippets

Acknowledgements

Nucl. Phys. A

Phys. Lett. B

Nucl. Phys. A

Nucl. Instrum. Methods Phys. Res. B

Nucl. Instrum. Methods Phys. Res. A

Nucl. Instrum. Methods Phys. Res. A

Phys. Lett. B

Nucl. Instrum. Methods Phys. Res. A

Nucl. Phys. A

At. Data Nucl. Data Tables

Phys. Rev. C

Comments Nucl. Part. Phys.

Phys. Rev. C

Phys. Rev. C

Phys. Rev. Lett.

Phys. Rev. C

Quadrupole collectivity in silicon isotopes approaching neutron number $N = 28$