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Effect of transients in nuclear fission on multiplicity of prescission neutrons

Gargi Chaudhuri·Santanu Pal
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Abstract

Transients in the fission of highly excited nuclei are studied in the framework of the Langevin equation. Time-dependent fission widths are calculated which show that after the initial transients, a steady flow towards the scission point is established not only for nuclei which have fission barriers but also for nuclei which have no fission barrier. It is shown from a comparison of the transient time and the fission life time that fission changes from a diffusive to a transient dominated process over a certain transition region as a function of the spin of the fissioning nucleus. Multiplicities of prescission neutrons are calculated in a statistical model with as well as without a single swoop description of fission and they are found to differ in the transition region. We however find that the difference is marginal and hence a single swoop picture of fission though not strictly valid in the transition region can still be used in the statistical model calculations.

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Gargi Chaudhuri, Santanu Pal. 2002-04-19. Effect of transients in nuclear fission on multiplicity of prescission neutrons. https://doi.org/10.1140/epja%2Fi2002-10010-4

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