Fine structure in the -decay of radium isotopes with mass numbers 209-212F.P. Heßberger1, S. Hofmann1 and D. Ackermann1, 2
1 Gesellschaft für Schwerionenforschung mbH, D-64220 Darmstadt, Germany
2 Institut für Physik, Johannes Gutenberg - Universität Mainz, D-55099 Mainz, Germany
(Received: 19 August 2002 / Revised version: 21 October 2002 / Published online: 18 February 2003)
Radium isotopes with mass numbers from 209 to 212 have been produced by heavy-ion fusion reactions ( , xn) . Radioactive decay properties were investigated by means of - and - -spectroscopy after in-flight separation of the evaporation residues from the projectile beam by the velocity filter SHIP and implantation into a 16-strip position-sensitive Si detector. For the even-even nuclei 210,212Ra we identified transitions into the first-excited 2 +-state of the daughter nuclei 206,208Rn. Weak transitions into excited levels of the odd- A daughter nuclei 205,207Rn were also observed.
23.60.+e - Alpha decay.
27.90.+b - .
© Società Italiana di Fisica, Springer-Verlag 2003