Eur. Phys. J. A (2004) 22: 417-427
https://doi.org/10.1140/epja/i2003-10238-4

Alpha-gamma decay studies of ^{251, 253}No and their daughter products ^{247, 249}Fm

¹ Gesellschaft für Schwerionenforschung mbH, D-64220, Darmstadt, Germany
² Institut für Physik, Johannes Gutenberg - Universität Mainz, D-55099, Mainz, Germany
³ Oliver Lodge Laboratory, University of Liverpool, L69 7ZE, Liverpool, UK
⁴ Department of Physics, University of Jyväskylä, FIN-40361, Finland

Received: 1 December 2003
Accepted: 27 June 2004
Published online: 9 November 2004

Abstract

The isotopes ²⁵¹No and ²⁵³No were produced in nuclear reactions ²⁰⁶Pb( ⁴⁸Ca,3n) ²⁵¹No and ²⁰⁷Pb( ⁴⁸Ca,2n) ²⁵³No. Radioactive decay of these isotopes and their daughter products has been investigated by means of α- and α-γ- spectroscopy. An isomeric state ^251mNo, having a half-life of T _1/2 = (0.93±0.06) s and decaying by emission of α particles of E _α = (8665±8) keV was identified. The measured decay data allowed for the construction of partial level schemes for ²⁵¹No, ^{247, 249}Fm and ^{243, 245}Cf and an extrapolation of energy systematics of single particle levels of N = 145, 147 and 149 isotones with even Z towards higher atomic numbers up to Z = 102.