Eur. Phys. J. A 14, 287-294 (2002)
DOI: 10.1140/epja/i2002-10010-4
Effect of transients in nuclear fission on multiplicity of prescission neutrons
Gargi Chaudhuri and Santanu PalVariable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064, India gargi@veccal.ernet.in
santanu@veccal.ernet.in
(Received: 2 April 2002 Communicated by W. Henning)
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 a steady flow towards the
scission point is established, after the initial transients, 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 lifetime 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.
05.40.Jc - Brownian motion.
24.60.Lz - Chaos in nuclear systems.
25.70.Jj - Fusion and fusion-fission reactions.
© Società Italiana di Fisica, Springer-Verlag 2002
