First Experiment on Fission Transients in Highly Fissile Spherical Nuclei Produced by Fragmentation of Radioactive Beams

Gesellschaft fuer Schwerionenforschung, 64291 Darmstadt, Germany.
Physical Review Letters (Impact Factor: 7.51). 08/2007; 99(4):042701. DOI: 10.1103/PhysRevLett.99.042701
Source: PubMed


We report on a novel experimental approach for studying the dissipative spreading of collective motion in a metastable nuclear system, using, for the first time, highly fissile nuclei with spherical shape. This was achieved by fragmentation of 45 radioactive heavy-ion beams at GSI, Darmstadt. The use of inverse kinematics and a dedicated experimental setup allowed for the identification in atomic number of both fission fragments. From the width of their nuclear-charge distributions, a transient time of (3.3+/-0.7)x10(-21) s is deduced for initially spherical nuclei.

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