Eur. Phys. J. A (2006) 29: 165-173
https://doi.org/10.1140/epja/i2006-10083-y

Nuclear Structure and Reactions

Alpha-gamma decay studies of ²⁵⁵No

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, Ibaraki, Japan
⁶ Flerov Laboratory of Nuclear Reactions, JINR, RUS-141890, Dubna, Russia
⁷ Institut für Physik, Johannes Gutenberg-Universität, D-55099, Mainz, Germany

Received: 2 May 2006
Accepted: 10 August 2006
Published online: 4 September 2006

Abstract

The decay of ²⁵⁵No was investigated by means of α-γ spectroscopy. The isotope was produced in the reactions ²⁰⁸Pb(⁴⁸Ca, n)²⁵⁵No, , and $²³⁸U(²²Ne, 5n)²⁵⁵No$. Levels of the daughter nucleus ²⁵¹Fm were assigned by α-γ coincidence measurements and on the basis of systematics. Level energies were determined precisely using measured γ-rays. The results are compared with the known level schemes of the lighter isotones ²⁴⁷Cm and ²⁴⁹Cf as well as with data for ²⁵³No.