Eur. Phys. J. A (2008) 38: 227-232
https://doi.org/10.1140/epja/i2008-10671-9

Regular Article - Experimental Physics

Di-nuclear systems studied with the velocity filter SHIP

¹ GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291, Darmstadt, Germany
² Institute of Technologies and Applied Sciences, 10400, Habana, Cuba
³ Institut für Physik, Goethe-Universität Frankfurt, D-60054, Frankfurt, Germany
⁴ Institute of Modern Physics, Chinese Academy of Sciences, 730000, Lanzhou, China
⁵ Japan Atomic Energy Agency (JAEA), 319-1195, Tokai, Ibaraki, Japan
⁶ DAPNIA / SPhN, CEA Saclay, F-91191, Gif-sur-Yvette Cedex, France

^* e-mail: s.heinz@gsi.de

Received: 20 August 2008
Revised: 15 October 2008
Accepted: 16 October 2008
Published online: 31 October 2008

Abstract

Various nuclear reactions like quasi-fission, fusion-fission or particle and cluster evaporation from excited compound nuclei were studied in heavy-ion reactions at the velocity filter SHIP of GSI. The velocity filter offers the possibility to detect all reaction products under zero degree relative to the beam direction. Together with the measurement of the product velocity distribution this allows for an identification of the underlying reaction mechanism. This article is focussed on reactions of ²⁵Mg and ⁶⁴Ni beams on ^{206, 207}Pb targets at energies of 5.9×AMeV and 8.7×AMeV . Besides evaporation residues from ²⁵Mg + ²⁰⁶Pb collisions we found evidence for rotation and quasi-fission of nuclear molecules formed in the entrance channel after the capture stage. The break-up of the systems showed a preferred clustering leading to isotopes in the region 84 ⩽ Z ⩽ 88 and 122 ⩽ N ⩽ 127 of the chart of nuclei.