a reduction of charged particle multiplicities.

Influence of excitation energy and angular momentum
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As shown in Fig. 10 an increase of the total excitation energy of the system from $26$ to $56$ MeV (which for a given angular momentum $L = 60 \hbar$ implies an increase of the thermal excitation energy) leads to a larger contribution to the symmetric fission mode. This result is obviously due to the vanishing of quantal effects when the nuclear temperature increases. However it can also be partly explained by a larger diffusion generated by the larger temperature (see Einstein relation). The corresponding larger oscillations thus allow the nucleus to [*explore more easily*]{} the energy landscape being able to overcome higher barriers and consequently to pass from one valley to another instead of being trapped preferentially in the deepest valley (which is asymmetric for the system presently considered). In ref  [@CS02] we also investigated the impact of the angular momentum on fission dynamics and obtained an relative increase of the symmetric fission cross section for increasing angular momentum due to a decrease of the fission barrier height.

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FIG. 10. Fission-fragment mass distributions for two different values of the total excitation energy of the 