Eur. Phys. J. A (2006) 30: 561-569
https://doi.org/10.1140/epja/i2006-10137-2

Nuclear Structure and Reactions

Alpha-gamma decay studies of ²⁵⁵Rf, ²⁵¹No and ²⁴⁷Fm

¹ Gesellschaft für Schwerionenforschung (GSI), D-64220, Darmstadt, Germany
² Institut für Physik, Johann Wolfgang Goethe - Universität Frankfurt, D-60054, Frankfurt, Germany
³ Department of Physics, Comenius University Bratislava, SK-84248, Bratislava, Slovakia
⁴ Department of Physics, University of Jyväskylä, FIN-40014, Jyväskylä, Finland
⁵ Japan Atomic Energy Agency (JAEA), 319-1195, Tokai, Ibaraki, Japan
⁶ Flerov Laboratory of Nuclear Reactions, JINR, RUS-141890, Dubna, Russia
⁷ Institut für Kernchemie, Johannes Gutenberg-Universität, D-55099, Mainz, Germany

Received: 2 August 2006
Accepted: 22 October 2006
Published online: 7 December 2006

Abstract

The decay of the isotopes ²⁵⁵Rf, ²⁵¹No and ²⁴⁷Fm produced in the reactions , and was investigated by means of α-γ spectroscopy. Previously observed γ transitions in coincidence with α decays of ²⁵⁵Rf were confirmed, their energies and line intensities were measured more precisely, and their multipolarities were determined as E1. In ²⁵¹No a new isomeric state at E ^* > 1700keV with a half-life of ≈ 2μs was identified. The decay of ²⁴⁷Fm was measured more precisely. A partial level scheme of the daughter nucleus ²⁴³Cf could be established.