Eur. Phys. J. A (2006) 28: 301-306
https://doi.org/10.1140/epja/i2006-10056-2

Nuclear Structure and Reactions

Recoil-fission tagging of the transfermium nucleus ²⁵²No

¹ Department of Physics, University of Jyväskylä, FIN-40351, Jyväskylä, Finland
² Oliver Lodge Laboratory, University of Liverpool, L69 7ZE, Liverpool, UK
³ DAPNIA/SPhN CEA-Saclay, F-91191, Gif-sur-Yvette Cedex, France
⁴ Department of Physical Sciences, University of Helsinki, FIN-00014, Helsinki, Finland
⁵ Gesellschaft für Schwerionenforschung, D-64220, Darmstadt, Germany
⁶ Argonne National Laboratory, Argonne, IL, USA
⁷ Ludwig Maximilians Universität, D-80539, München, Germany
⁸ IPNL, 69622, Villeurbanne Cedex, France

Received: 16 March 2006
Accepted: 5 June 2006
Published online: 23 June 2006

Abstract

An in-beam study of the transfermium nucleus ²⁵²No has been performed using the JUROSPHERE II array of germanium detectors coupled to the gas-filled recoil separator RITU. A new technique of recoil-fission tagging was used to extract tagged γ-ray data. Having significant spontaneous fission and α-decay branches, ²⁵²No is an ideal candidate for a comparative study. In a similar manner to α-decay tagging the fission events can be used to obtain γ-ray data. The recoil-fission tagged γ-ray spectrum showed a similar structure to the α-decay tagged γ-ray spectrum. By comparing the α-tagged and fission-tagged spectra and decay curves, it was shown that the spontaneous fission originates from the same initial state as the α decay. This extension of the tagging method allows in-beam spectroscopic data to be obtained from heavy nuclei with significant spontaneous-fission branches.