Abstract. Isotope shifts and hyperfine structures have been measured for radioisotopes of ionic zirconium using on-line laser spectroscopy at the IGISOL facility in Jyväskylä, where the installation of an ion beam cooler/buncher has significantly improved the experimental sensitivity. Measurements have been made on all the neutron-deficient isotopes from ⁸⁷Zr to ⁹⁰Zr, including the isomers ^87m,89mZr, and the neutron-rich isotopes from ⁹⁶Zr to ¹⁰²Zr. The change in mean square charge radii between the isotopes and the nuclear moments of the odd isotopes have been extracted. The data show a sudden increase in the mean square charge radius at mass A = 100, consistent with an onset of nuclear deformation which has been observed in the gamma ray spectroscopy of isotope chains in this region of the nuclear chart.

Print publication: Issue 9 (September 2003)
Received 16 April 2003, in final form 10 June 2003
Published 4 August 2003