RESUMEN
Differences in mean-square nuclear charge radii of ^{100-130}Cd are extracted from high-resolution collinear laser spectroscopy of the 5s ^{2}S_{1/2}â5p ^{2}P_{3/2} transition of the ion and from the 5s5p ^{3}P_{2}â5s6s ^{3}S_{1} transition in atomic Cd. The radii show a smooth parabolic behavior on top of a linear trend and a regular odd-even staggering across the almost complete sdgh shell. They serve as a first test for a recently established new Fayans functional and show a remarkably good agreement in the trend as well as in the total nuclear charge radius.
RESUMEN
Isomer shifts have been determined in ^{111-129}Cd by high-resolution laser spectroscopy at CERN-ISOLDE. The corresponding mean square charge-radii changes, from the 1/2^{+} and the 3/2^{+} ground states to the 11/2^{-} isomers, have been found to follow a distinct parabolic dependence as a function of the atomic mass number. Since the isomers have been previously associated with simplicity due to the linear mass dependence of their quadrupole moments, the regularity of the isomer shifts suggests a higher order of symmetry affecting the ground states in addition. A comprehensive description assuming nuclear deformation is found to accurately reproduce the radii differences in conjunction with the known quadrupole moments. This intuitive interpretation is supported by covariant density functional theory.
RESUMEN
A marked difference in the nuclear charge radius was observed between the I^{π}=3^{+} ground state and the I^{π}=0^{+} isomer of ^{38}K and is qualitatively explained using an intuitive picture of proton-neutron pairing. In a high-precision measurement of the isomer shift using bunched-beam collinear laser spectroscopy at CERN-ISOLDE, a change in the mean-square charge radius of ⟨r_{c}^{2}⟩(^{38}K^{m})-⟨r_{c}^{2}⟩(^{38}K^{g})=0.100(6) fm^{2} was obtained. This is an order of magnitude more accurate than the result of a previous indirect measurement from which it was concluded that both long-lived states in ^{38}K have similar charge radii. Our observation leads to a substantially different understanding since the difference in charge radius is, moreover, opposite in sign to previously reported theoretical predictions. It is demonstrated that the observed isomer shift can be reproduced by large-scale shell-model calculations including proton and neutron excitations across the N,Z=20 shell gaps, confirming the significance of cross-shell correlations in the region of ^{40}Ca.
RESUMEN
The ground-state spins and magnetic moments of (49,51)K have been measured using bunched-beam high-resolution collinear laser spectroscopy at ISOLDE CERN. For 49K a ground-state spin I = 1/2 was firmly established. The observed hyperfine structure of 51K requires a spin I > 1/2 and strongly suggests I = 3/2. From its magnetic moment µ(51K) = +0.5129(22)µ(N) a spin-parity I(π) = 3/2+ with a dominant π1d(3/2)(-1) hole configuration was deduced. This establishes for the first time the reinversion of the single-particle levels and illustrates the prominent role of the residual monopole interaction for single-particle levels and shell evolution.
RESUMEN
The neutron-rich isotopes of cadmium up to the N=82 shell closure have been investigated by high-resolution laser spectroscopy. Deep-uv excitation at 214.5 nm and radioactive-beam bunching provided the required experimental sensitivity. Long-lived isomers are observed in (127)Cd and (129)Cd for the first time. One essential feature of the spherical shell model is unambiguously confirmed by a linear increase of the 11/2(-) quadrupole moments. Remarkably, this mechanism is found to act well beyond the h(11/2) shell.
RESUMEN
The nuclear charge radius of (12)Be was precisely determined using the technique of collinear laser spectroscopy on the 2s(1/2)â2p(1/2,3/2) transition in the Be(+) ion. The mean square charge radius increases from (10)Be to (12)Be by δ
RESUMEN
Charge radii of all magnesium isotopes in the sd shell have been measured, revealing evolution of the nuclear shape throughout two prominent regions of assumed deformation centered on (24)Mg and (32)Mg. A striking correspondence is found between the nuclear charge radius and the neutron shell structure. The importance of cluster configurations towards N=8 and collectivity near N=20 is discussed in the framework of the fermionic molecular dynamics model. These essential results have been made possible by the first application of laser-induced nuclear orientation for isotope shift measurements.