Transport coefficients in the Langevin equation are essential for the dynamical analysis of nuclear fission. Two primary methods for calculating these coefficients exist: macroscopic and microscopic. Here we study the fission of ${}^{236}\mathrm{U}$ using a five-dimensional Langevin equation with a Cassini shape parametrization to examine how the choice of transport coefficients affects the distributions of fission fragment mass, quadrupole $\left({\beta }_2\right)$, octupole $\left({\beta }_3\right)$, and total kinetic energy. The results indicate that microscopic transport coefficients generate fragments with a broader range of deformation, which improves the agreement with experimental mass distributions for asymmetric fission modes. This improvement is found to be primarily due to the microscopic inertia tensor. To assess the effectiveness of the five-dimensional parametrization, the results are compared with those from lower-dimensional calculations. The Cassini parameter set $\{\alpha ,{\alpha }_1,{\alpha }_3,{\alpha }_4,{\alpha }_6\}$ is shown to properly describe both mass asymmetry and superlong symmetric fission. Furthermore, a rare type of hot fission is observed for heavy fragment masses of $134\pm 2$, characterized by a superelongated, neck-shaped light fragment.

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• Fission
• A ≥ 220
• Nuclear reactions