S. G. Wilkins

Use of a Continuous Wave Laser and Pockels Cell for Sensitive High-Resolution Collinear Resonance Ionization Spectroscopy.

New technical developments have led to a 2 orders of magnitude improvement of the resolution of the collinear resonance ionization spectroscopy (CRIS) experiment at ISOLDE, CERN, without sacrificing the high efficiency of the CRIS technique. Experimental linewidths of 20(1) MHz were obtained on radioactive beams of francium, allowing us for the first time to determine the electric quadrupole moment of the short lived [t_{1/2}=22.0(5) ms] ^{219}Fr Q_{s}=-1.21(2) eb, which would not have been possible without the advantages offered by the new method. This method relies on a continuous-wave laser and an external Pockels cell to produce narrow-band light pulses, required to reach the high resolution in two-step resonance ionization. Exotic nuclei produced at rates of a few hundred ions/s can now be studied with high resolution, allowing detailed studies of the anchor points for nuclear theories.

arXiv : Dipole and quadrupole moments of

Nuclear spins and precise values of the magnetic dipole and electric quadrupole moments of the ground-states of neutron-rich

^{73-78}

^{76-78}

Cu as a test of the robustness of the

Cu isotopes were measured using the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, CERN. The nuclear moments of the less exotic

Z=28

^{73,75}

shell closure near

Cu isotopes were re-measured with similar precision, yielding values that are consistent with earlier measurements. The moments of the odd-odd isotopes, and

^{78}

^{78}_{29}

Ni

Cu (

Combined high-resolution laser spectroscopy and nuclear decay spectroscopy for the study of the low-lying states in Fr 206, at 202, and Bi 198

N=49

Laser and decay spectroscopy of the short-lived isotope 214Fr in the vicinity of the N = 126 shell closure

) in particular, are used to investigate excitations of the assumed doubly-magic