Dynamical decay of a trinuclear system in the presence of friction forces in the spontaneous fission of Cf252

The dynamics of the rupture of the ternary system $^{70}\mathrm{Ni}+^{50}\mathrm{Ca}+^{132}\mathrm{Sn}$ formed at the spontaneous fission of $^{252}\mathrm{Cf}$ has been studied. The heaviest fragment $^{132}\mathrm{Sn}$ is separated first very easily and the behavior of the breakup of the $^{70}\mathrm{Ni}+^{50}\mathrm{Ca}$ system determines final directions of the angular distribution of the final products. The equations of motion with including microscopical friction forces between two contacting nuclei have been calculated. The friction force in the dynamical equations results in increase of decay time of the system only. The results of calculations show that the trajectory of the middle Ca nucleus is nearly perpendicular to the line connecting centers of two massive $^{70}\mathrm{Ni}$ and $^{132}\mathrm{Sn}$ nuclei if initial configuration is not collinear.