Studies of Fission Hindrance in Hot Nuclei
نویسندگان
چکیده
The study of dissipation in hot nuclear systems is a subject of great current interest. Different experimental techniques and observables have recently been utilized which are sensitive to the dissipation in large-scale shape rearrangements, such as those encountered in heavyion Eusion, fission and quasifission reactions. To study the dynamical shape evolution of hot nuclear systems it is necessary to measure properties (or processes) that are sensitive to the time-scale on which these shape changes occur. Several methods, such as the emission of prescission particles (n, p and a) and y-rays, have been used to study the fission time-scale in relation to these (well known) decay processes. Recently it has also been pointed out that measurements of the evaporation residue cross section, which are very sensitive to the competition between particle emission and fission, probe the fission time-scale. This paper will present recent studies of the evaporation residue cross section in the 32S+184W system carried out at the ATLAS Fragment Mass Analyzer, including the methods for obtaining absolute cross sections. The submitted manuscript har been authored by a contrectw of the U.S. Governmant i I under contract No. W.31-104ENG-38. I Accordingly, the U. S. Government retains a nonexclusive. royalty-free hcense to plblirh or reproduce the published form of thtr contribution, or allow others to do SO, for MASTER ‘ 1 U. S. Government wrwses. I . . I
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