6533b85cfe1ef96bd12bcb7c

RESEARCH PRODUCT

Nuclear charge radii and electromagnetic moments of radioactive scandium isotopes and isomers

subject

description

International audience; Collinear laser spectroscopy experiments with the Sc + transition 3d4s 3 D 2 → 3d4p 3 F 3 at λ = 363.1 nm were performed on the 42−46 Sc isotopic chain using an ion guide isotope separator with a cooler-buncher. Nuclear magnetic dipole and electric quadrupole moments as well as isotope shifts were determined from the hyperfine structure for five ground states and two isomers. Extensive multi-configurational Dirac-Fock calculations were performed in order to evaluate the specific mass-shift, M SMS, and field-shift, F, parameters which allowed evaluation of the charge radii trend of the Sc isotopic sequence. The charge radii obtained show systematics more like the Ti radii, which increase towards the neutron shell closure N = 20, than the symmetric parabolic curve for Ca. The changes in mean square charge radii of the isomeric states relative to the ground states for 44 Sc and 45 Sc were also extracted. The charge radii difference between the ground and isomeric states of 45 Sc is in agreement with the deformation effect estimated from the B(E2) measurements but is smaller than the deformation extracted from the spectroscopic quadrupole moments.