Impact of Nuclear Deformation and Pairing on the Charge Radii of Palladium Isotopes

• Published in: Physical review letters 2022-04, Vol.128 (15), p.152501-152501, Article 152501
• Main Authors: Geldhof, S, Kortelainen, M, Beliuskina, O, Campbell, P, Caceres, L, Cañete, L, Cheal, B, Chrysalidis, K, Devlin, C S, de Groote, R P, de Roubin, A, Eronen, T, Ge, Z, Gins, W, Koszorus, A, Kujanpää, S, Nesterenko, D, Ortiz-Cortes, A, Pohjalainen, I, Moore, I D, Raggio, A, Reponen, M, Romero, J, Sommer, F
• Format: Article
• Language: English
• Subjects: Nuclear Experiment; Physics
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.128.152501

The impact of nuclear deformation can been seen in the systematics of nuclear charge radii, with radii generally expanding with increasing deformation. In this Letter, we present a detailed analysis of the precise relationship between nuclear quadrupole deformation and the nuclear size. Our approach combines the first measurements of the changes in the mean-square charge radii of well-deformed palladium isotopes between A=98 and A=118 with nuclear density functional calculations using Fayans functionals, specifically Fy(std) and Fy(Δr,HFB), and the UNEDF2 functional. The changes in mean-square charge radii are extracted from collinear laser spectroscopy measurements on the 4d^{9}5s ^{3}D_{3}→4d^{9}5p ^{3}P_{2} atomic transition. The analysis of the Fayans functional calculations reveals a clear link between a good reproduction of the charge radii for the neutron-rich Pd isotopes and the overestimated odd-even staggering: Both aspects can be attributed to the strength of the pairing correlations in the particular functional which we employ.