Eur. Phys. J. Special Topics 150, 31-34 (2007)
https://doi.org/10.1140/epjst/e2007-00258-8

Isovector deformation and its link to the neutron shell closure

Institute for Nuclear Science & Technique, P.O. Box 5, VAEC, Hanoi, Vietnam

Corresponding author: khoa@vaec.gov.vn

Received: 31 January 2007
Published online: 8 December 2007

Abstract

DWBA analysis of the inelastic ^30-40S(p,p') and ^18-22O(p,p') scattering data measured in the inverse kinematics has been performed to determine the isoscalar (δ₀) and isovector (δ₁) deformation lengths of the 2⁺₁ excitations in the Sulfur and Oxygen isotopes using a compact folding approach. A systematic N-dependence of δ₀ and δ₁ has been established which shows a link between δ₁ and the neutron-shell closure. Strong isovector deformations were found in several cases, e.g., the 2⁺₁ state in ²⁰O where δ₁ is nearly three times larger than δ₀. These results confirm the relation δ₁>δ₀ anticipated from the core polarization by the valence neutrons in the open-shell (neutron rich) nuclei. The effect of neutron shell closure at N=14 or 16 has been discussed based on the folding model analysis of the inelastic ²²O+p scattering data at 46.6 MeV/u measured recently at GANIL.