Measurement of the Dipole Polarizability of the Unstable Neutron-Rich Nucleus Ni-68
Publication Type
Journal Article
Year of Publication
2013
Name of Publication
Physical Review Lettersv
Volume
111
Issue
24
Date Published
Dec
Short Title
Measurement of the Dipole Polarizability of the Unstable Neutron-Rich Nucleus Ni-68
Accession Number
WOS:000328699400005
ISBN Number
031-9007
Abstract
The E1 strength distribution in Ni-68 has been investigated using Coulomb excitation in inverse kinematics at the (RB)-B-3-LAND setup and by measuring the invariant mass in the one-and two-neutron decay channels. The giant dipole resonance and a low-lying peak (pygmy dipole resonance) have been observed at 17.1(2) and 9.55(17) MeV, respectively. The measured dipole polarizability is compared to relativistic random phase approximation calculations yielding a neutron-skin thickness of 0.17(2) fm. A method and analysis applicable to neutron-rich nuclei has been developed, allowing for a precise determination of neutron skins in nuclei as a function of neutron excess.