V. P. Denisov

Nuclear electromagnetic moments and charge radii of deformed thulium isotopes with the mass numbers A = 157−172

Abstract Hyperfine structures and isotope shifts of thulium isotopes in the mass range 157–172 have been measured in the atomic transitions 4f 13 6s 2 −4f 12 5d6s 2 (589.565 nm) and 6s 2 −6s6p (597.13 nm), using resonance ionization Spectroscopy at the IRIS facility. Nuclear magnetic dipole and electric quadrupole moments, and the changes in mean square charge radii have been obtained. They are analysed within the framework of the microscopic-macroscopic approach and the Hartree-Fock method, revealing single-particle and collective properties. Some conclusions on effective nucleon-nucleon interactions are drawn.

Nuclear deformation of holmium isotopes

Abstract Hyperfine structures and isotope shifts of holmium isotopes and isomers in the mass range 152–165 have been measured for the atomic transition of 592.17 nm using resonance ionization Spectroscopy. Nuclear magnetic dipole and electric quadrupole moments, and changes in mean square charge radii have been derived from the results. Nuclear spins for some isotopes and isomers have been determined too. A sudden change of nuclear deformation between N = 89 and N = 90 has been found. The experimental data are discussed within the framework of the macroscopic-microscopic approach and the Hartree-Fock method. The intrinsic quadrupole moments, including their change at N = 89–90, are described fairly well. At the same time, some difficulties in the description of the mean square charge radii by the Hartree-Fock theory have been revealed.

Investigation of the release properties of MeCx targets at IRIS

Abstract The technology of preparation of the MeC x targets (Me = U, Th, Zr and Gd) is described. The results of the investigations on the release properties for this kind of target material are discussed. The production yields of some isotopes far from stability obtained at the IRIS facility from these targets are presented.

Electromagnetic moments and nuclear charge radii for neutron-deficient Tb isotopes and the deformation jump nearZ=64,N=90

Optical isotope shifts and hyperfine structures of the147–153,155,157,159 Tb isotopes have been measured by the resonance ionization spectroscopy method. Nuclear moments and changes in nuclear charge radiiΔ 〈r2〉 have been deduced. The “jump” inΔ 〈r2〉 atN=88–90 has been revealed. It is compared with the relevant data for nuclei with other proton numbers.

Odd-even staggering in nuclear charge radii of neutron-rich europium isotopes

Nuclear magnetic dipole and electric quadrupole moments and changes in mean square charge radii for the neutron-rich155–159Eu isotopes have been measured using resonance ionization spectroscopy at the IRIS facility. It has been found that the isotopes withN>92, unlike the isotopes with 89≦N≦92, have an ordinary character of odd-even staggering in nuclear charge radii. This means that the octupole deformation attributed previously to the europium nuclei around154Eu does not display itself in the charge radii of heavier europium isotopes.

Investigation of nuclear charge radii and electromagnetic moments of rare earth elements by laser spectroscopy

Isotope shifts and hyperfine structure of optical lines of neodymium isotopes with the mass numbers A=132, 134–142, samarium isotopes with A=138–145, 147, 149, 150, 152, 154, europium isotopes with A=138–151, holmium isotopes with A=152–165, and thulium isotopes with A=156–172 have been studies at the IRIS mass separator laser nuclear facility. For these isotopes, nuclear electromagnetic moments and isotopic changes in mean square charge radii are determined. Characteristic features of the charge radii N‐dependence in the regions at N<82 and 88