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Nonequilibrium information entropy approach to ternary fission of actinides

Journal Article · · Physical Review. C
 [1];  [2];  [3]
  1. Univ. Rostock (Germany). Inst. for Physics; OSTI
  2. Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.
  3. Univ. of Coimbra (Portugal). CFisUC
+ Show Author Affiliations
Ternary fission of actinides probes the state of the nucleus at scission. Light clusters are produced in space and time very close to the scission point. Within the nonequilibrium statistical operator method, a generalized Gibbs distribution is constructed from the information given by the observed yields of isotopes. Using this relevant statistical operator, yields are calculated taking excited states and continuum correlations into account, in accordance with the virial expansion of the equation of state. Furthermore, clusters with mass number A≤10 are well described using the nonequilibrium generalizations of temperature and chemical potentials. Improving the virial expansion, in-medium effects may become of importance in determining the contribution of weakly bound states and continuum correlations to the intrinsic partition function. Yields of larger clusters, which fail to reach this quasiequilibrium form of the relevant distribution, are described by nucleation kinetics, and a saddle-to-scission relaxation time of about 7000 fm/c is inferred. Light-charged particle emission, described by reaction kinetics and virial expansions, may therefore be regarded as a very important tool to probe the nonequilibrium time evolution of actinide nuclei during fission.
Research Organization:
Texas A & M Univ., College Station, TX (United States)
Sponsoring Organization:
FCT Portugal; German Research Foundation (DFG); USDOE Office of Science (SC)
Grant/Contract Number:
FG02-93ER40773
OSTI ID:
1850048
Journal Information:
Physical Review. C, Journal Name: Physical Review. C Journal Issue: 6 Vol. 103; ISSN PRVCAN; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS
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fission
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