Laser Spectroscopy of Niobium Fission Fragments: First Use of Optical Pumping in an Ion Beam Cooler Buncher

Research output: Contribution to journalArticlepeer-review


  • B Cheal
  • K Baczynska
  • J Billowes
  • P Campbell
  • FC Charlwood
  • T Eronen
  • A Jokinen
  • T Kessler
  • ID Moore
  • M Reponen
  • S Rothe
  • M Rueffer
  • A Saastamoinen
  • J Aysto

Colleges, School and Institutes


A new method of optical pumping in an ion beam cooler buncher has been developed to selectively enhance ionic metastable state populations. The technique permits the study of elements previously inaccessible to laser spectroscopy and has been applied here to the study of Nb. Model independent mean-square charge radii and nuclear moments have been studied for \(^{90,90 m,91,91 m,92,93,99,101,103}\)Nb to cover the region of the N=50 shell closure and N≈60 sudden onset of deformation. The increase in mean-square charge radius is observed to be less than that for Y, with a substantial degree of β softness observed before and after N=60.


Original languageEnglish
Pages (from-to)222501
Number of pages1
JournalPhysical Review Letters
Issue number22
Publication statusPublished - 1 Jun 2009