Zhang, ZY (reprint author), Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.
In deeply inelastic heavy-ion collisions, the quadrupole deformations of both fragments are taken as stochastic independent dynamical variables governed by the Fokker-Planck equation (FPE) under the corresponding driving potential. The mean values, variances and covariance of the fragments are analytically expressed by solving the FPE in head on collisions. The characteristics and mechanism of the deformation are discussed. It is found that both the internal structures and interactions of the colliding partners are critical for the deformation relaxation in deeply inelastic collisions. (C) 2014 The Authors. Published by Elsevier B.V.