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© 2018 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. The neutron-deficient cadmium isotopes have been measured by high-resolution laser spectroscopy at CERN-ISOLDE. The electromagnetic moments of Cd101 have been determined for the first time and the quadrupole-moment precision of Cd103 has been vastly improved. The results on the sequence of 5/2+ ground states in Cd101-109 are tentatively discussed in the context of simple structure in complex nuclei as similarities are found with the 11/2- states in the neutron-rich cases. Comparison with shell-model calculations reveals a prominent role of the two holes in the Z=50 core. ispartof: Physical Review C vol:98 issue:1 status: published

The neutron-deficient cadmium isotopes have been measured by high-resolution laser spectroscopy at CERN-ISOLDE. The electromagnetic moments of 101Cd have been determined for the first time and the quadrupole-moment precision of 103Cd has been vastly improved. The results on the sequence of 5/2+ ground states in 101–109Cd are tentatively discussed in the context of simple structure in complex nuclei as similarities are found with the 11/2− states in the neutron-rich cases. Comparison with shell-model calculations reveals a prominent role of the two holes in the Z=50 core.

Isomer shifts have been determined in 111–129Cd 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. ispartof: Physical Review Letters vol:116 issue:3 pages:1-5 ispartof: location:United States status: published

The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58;60;62;64Mn are now firmly determined to be I = 1 along with an I = 4 assignment for the isomeric states in 58;60;62Mn. The I = 1 magnetic moments show a decreasing trend with increasing neutron number while the I = 4 moments remain quite constant between N = 33 and N = 37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellent agreement of the ground state moments with the predictions from the LNPS calculations illustrates the need for an increasing amount of proton excitations across Z = 28 and neutron excitations across N = 40 in the ground state wave functions from N = 37 onwards. The odd-odd Mn54,56,58,60,62,64 isotopes (Z=25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N=39 were extracted. The previous tentative ground state spin assignments of Mn58,60,62,64 are now firmly determined to be I=1 along with an I=4 assignment for the isomeric states in Mn58,60,62. The I=1 magnetic moments show a decreasing trend with increasing neutron number while the I=4 moments remain quite constant between N=33 and N=37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellent agreement of the ground state moments with the predictions from the LNPS calculations illustrates the need for an increasing amount of proton excitations across Z=28 and neutron excitations across N=40 in the ground state wave functions from N=37 onwards. The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58;60;62;64Mn are now firmly det

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 Cd127 and Cd129 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 h11/2 shell.

The nuclear charge radius of $^{12}$Be was precisely determined using the technique of collinear laser spectroscopy on the $2s_{1/2}\rightarrow 2p_{1/2, 3/2}$ transition in the Be$^{+}$ ion. The mean square charge radius increases from $^{10}$Be to $^{12}$Be by $\delta ^{10,12} = 0.69(5) \fm^{2}$ compared to $\delta ^{10,11} = 0.49(5) \fm^{2}$ for the one-neutron halo isotope $^{11}$Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of $^{12}$Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure., Comment: 5 pages, 3 figures

Collinear laser spectroscopy was performed on the 63,64,66,68−82Ga isotopes with neutron numbers from N = 32 to N = 51. These measurements were carried out at the ISOLDE radioactive ion beam facility at CERN. Here we present the nuclear mean-square charge radii extracted from the isotope shifts and, for the lighter isotopes, new spin and moment values. New ground-state nuclear spin and moments were extracted from the hyperfine spectra of 63,70Ga, measured on an atomic transition in the neutral atom. The ground-state spin of 63Ga is determined to be I = 3/2. Analysis of the trend in the change in mean-square charge radii of the gallium isotopes demonstrates that there is no evidence of anomalous charge radii behavior in gallium in the region of N = 32. peerReviewed

Laser spectroscopy was performed on the 72,74,76,78Ga isotopes at On-Line Isotope Mass Separator (ISOLDE) facility, CERN. Ground-state nuclear spins and moments were extracted from the measured hyperfine spectra. The results are compared to shell-model calculations, which provide a detailed probe of the nuclear wave function. The spin is established from the shape of the hyperfine structure and the parity inferred from a comparison of shell-model calculations with the measured nuclear moments. The ground states of 76,78Ga are both assigned a spin and parity of Iπ=2−, while 74Ga is tentatively assigned as Iπ=3−. For 72Ga, the results are consistent with the previous I=3 assignment.

Measurements of the ground-state nuclear spins, magnetic and quadrupole moments of the copper isotopes from 61Cu up to 75Cu are reported. The experiments were performed at the ISOLDE facility, using the technique of collinear laser spectroscopy. The trend in the magnetic moments between the N=28 and N=50 shell closures is reasonably reproduced by large-scale shell-model calculations starting from a 56Ni core. The quadrupole moments reveal a strong polarization of the underlying Ni core when the neutron shell is opened, which is however strongly reduced at N=40 due to the parity change between the $pf$ and $g$ orbits. No enhanced core polarization is seen beyond N=40. Deviations between measured and calculated moments are attributed to the softness of the 56Ni core and weakening of the Z=28 and N=28 shell gaps., 13 pagers, 19 figures, accepted by Physical Review C

Measurements of the ground-state nuclear spins and magnetic and quadrupole moments of the copper isotopes from 61Cu up to 75Cu are reported. The experiments were performed at the CERN online isotope mass separator (ISOLDE) facility, using the technique of collinear laser spectroscopy. The trend in the magnetic moments between the N=28 and N=50 shell closures is reasonably reproduced by large-scale shell-model calculations starting from a 56Ni core. The quadrupole moments reveal a strong polarization of the underlying Ni core when the neutron shell is opened, which is, however, strongly reduced at N=40 due to the parity change between the pf and g orbits. No enhanced core polarization is seen beyond N=40. Deviations between measured and calculated moments are attributed to the softness of the 56Ni core and weakening of the Z=28 and N=28 shell gaps.

This article reports on the ground-state spin and moments measured in 72,74Cu using collinear laser spectroscopy at the CERN On-Line Isotope Mass Separator (ISOLDE) facility. From the measured hyperfine coefficients, the nuclear observables μ(72Cu)=-1.3472(10)μN, μ(74Cu)=-1.068(3)μN, Q(72Cu)=+8(2) efm2, Q(74Cu)=+26(3) efm2, I(72Cu)=2, and I(74Cu)=2 have been determined. Through a comparison of the measured magnetic moments with different models, the negative moment reveals a strong πf5/2⊗νg9/2 component in the ground-state wave function. Consequently, a negative parity has been assigned to the ground states of 72,74Cu. Large-scale shell-model calculations illustrate the strong sensitivity of the nuclear moments to configuration mixing and to the effective interaction employed.

The nuclear charge radii of $^{7,9,10,11}$Be have been determined by high-precision laser spectroscopy. On-line measurements were performed at ISOLDE with collinear laser spectroscopy in the $2s_{1/2} \to 2p_{1/2}$ transition of Be$^{+}$. Simultaneous measurements in collinear and anti-collinear direction combined with absolute frequency determination using a frequency comb yielded accuracy in the isotope shift measurements of better than 1 MHz. Combined with accurate calculations of the mass-dependent isotope shifts the nuclear charge radii along the isotopic chain were extracted. The charge radius decreases from $^7$Be to $^{10}$Be and then increases for the halo nucleus $^{11}$Be. When comparing our results with predictions of {\it ab-initio} nuclear structure calculations we find good agreement. Additionally, the nuclear magnetic moment of $^7$Be was determined to be 1.3998(15) $\mu_{\rm N}$ and that of $^{11}$Be was confirmed with an accuracy similar to previous $\beta$-NMR measurements. The nuclear charge radii of $^{7,9,10,11}$Be have been determined by high-precision laser spectroscopy. On-line measurements were performed at ISOLDE with collinear laser spectroscopy in the $2s_{1/2} \to 2p_{1/2}$ transition of Be$^{+}$. Simultaneous measurements in collinear and anti-collinear direction combined with absolute frequency determination using a frequency comb yielded accuracy in the isotope shift measurements of better than 1 MHz. Combined with accurate calculations of the mass-dependent isotope shifts the nuclear charge radii along the isotopic chain were extracted. The charge radius decreases from $^7$Be to $^{10}$Be and then increases for the halo nucleus $^{11}$Be. When comparing our results with predictions of {\it ab-initio} nuclear structure calculations we find good agreement. Additionally, the nuclear magnetic moment of $^7$Be was determined to be -1.3995(5) $\mu_{\rm N}$ and that of $^{11}$Be was confirmed with an accuracy similar to previous $\beta$-NMR measurements.

Nuclear charge radii of $^{7,9,10,11}$Be have been determined by high-precision laser spectroscopy. On-line measurements were performed with collinear laser spectroscopy in the $2s_{1/2} \to 2p_{1/2}$ transition on a beam of Be$^{+}$ ions. Collinear and anticollinear laser beams were used simultaneously and the absolute frequency determination using a frequency comb yielded an accuracy in the isotope-shift measurements of about 1 MHz. Combination with accurate calculations of the mass-dependent isotope shifts yield nuclear charge radii. The charge radius decreases from $^7$Be to $^{10}$Be and then increases for the halo nucleus $^{11}$Be. When comparing our results with predictions of {\it ab initio} nuclear structure calculations we find good agreement. Additionally, the nuclear magnetic moment of $^7$Be was determined to be $-1.3995(5)\mu_{\rm N}$ and that of $^{11}$Be from a previous $\beta$-NMR measurement was confirmed., Comment: 4 pages, 2 figures calculated mass shift values have been re-evaluated with the latest mass values for the beryllium isotopes and the nuclear polarization contribution for Be-11, published by K. Pachucki et al. ater submission of our manuscript, is also included now