Eur. Phys. J. Special Topics 150, 293-296 (2007)
https://doi.org/10.1140/epjst/e2007-00327-0

ISOL beams of hafnium isotopes and isomers^*

¹ ISOLDE, CERN, 1211 Genève 23, Switzerland
² Institut Laue Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9, France
³ Institut für Kernchemie, Universität Mainz, 55128 Mainz, Germany
⁴ Paul Scherrer Institut, Laboratory for Radio and Environmental Chemistry, 5232 Villigen PSI, Switzerland
⁵ GSI, Planckstrasse 1, 64291 Darmstadt, Germany
⁶ Weizmann Institute of Sciences, Dept. of Particle Physics, Rehovot, 76100, Israel

Received: 31 January 2007
Published online: 8 December 2007

Abstract

The production of ISOL beams of hafnium is described. Radioactive Hf isotopes were produced at ISOLDE by 1.4 GeV proton-induced spallation in Ta and W foils. Chemical evaporation in form of HfF₄ and mass separation in the molecular sideband HfF₃⁺ after electron impact ionization provided intense and pure beams. Beams of ^158-185Hf and short-lived isomers down to 1.1 s ^177mHf were observed, but the method could be extended to reach even more exotic isotopes: down to about ¹⁵⁴Hf (N=82) on the neutron-deficient side and up to neutron-rich ¹⁸⁸Hf.