takes place. The broad distribution related to $c_{scis} \!=\! 1.8$ can be easily understood with Fig. $6$ where the quite flat potential landscape in the $\alpha$ direction around $c \approx 1.8$ can give rise to a large variety of mass partitions. In spite of this, the final distribution at $c_{geo}$ is rather strongly asymmetric. Moreover the value $c \!=\! 1.8$ corresponds to a quite important elongation, i.e. an elongation for which one can already have a reasonable idea of the asymmetry of the nascent fission fragments [@NPPW79]. The present investigation points out the importance of quantal effects for $c \!>\! 1.8$ and with it the necessity of their accurate determination for these largest deformations. To avoid problems related to the choice of this one-center basis we perform the diagonalisation taking a very large number of basis states into account.

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FIG. 11. Fission-fragment mass distributions obtained for the system $^{227}$Pa ($E^*_{tot} = 56$ MeV, $L = 60 \hbar$) for $c_{scis} \!=\! 1.8$ and $c_{scis} \!=\! c_{geo}$ (see text).\

Temperature dependence of transport coefficients
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As mentioned in section 2.2. we probably overestimate friction at low temperature. As demonstrated on Fig. 12 the reduction of friction by a factor of two 