respectively [@SPS01].\

Theoretical results of fission dynamics
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Influence of quantal effects
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### One- versus 2-dimensional Langevin equation

In the framework of the 2-dimensional Langevin equation solved in the ($c, \alpha$) deformation space, the LDM energy landscape is displayed on Fig. 5 together with a typical fission trajectory for the compound nucleus $^{227}$Pa at a total excitation energy of $E^*_{tot} \!=\! 26$ MeV and an angular momentum of $L = 60 \hbar$. We choose this specific nuclear system because it was the object of a recent experimental campaign [@CS02]. As no shell effects are taken into account here, only the symmetric fission valley is present. Consequently the compound nucleus starting from its ground-state deformation ($c \!=\! 1.11 , \alpha \!=\! 0$), naturally ends up in the symmetric fission channel. In this calculation we have not coupled particle emission to the Langevin equation and therefore cannot make any statement on particle multiplicities. The fission time, defined as the average time which a trajectory takes to reach the scission point, is in the present 2-dimensional treatment reduced by about 7% (5.96 $10^{-17}$ sec versus 6.36 $10^{-17}$ sec) as compared to its 1-dimensional value [@CSLi00].

Let us try to understand this result 