Dynamical effects in the fusion hindrance

¹ GANIL, CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen, France
² Université de Caen Basse-Normandie, F-14032 Caen Cedex, France
³ School of Science, Huzhou Tearchers College, Huzhou, 313000 Zhejiang, P.R. China
⁴ RCNP, Osaka Univ., Ibaraki, 567-0047 Osaka, Japan
⁵ Institut Physique Théorique, CEA/DSM, Centre d’Etudes de Saclay, Gif-sur-Yvette, F-91191, France

^a e-mail: boilley@ganil.fr

Abstract

It is well known that there is a hindrance to fusion in collisions with heavy nuclei that plays a decisive role in synthesis of the super-heavy elements (SHE). The origin of the fusion hindrance is nowadays qualitatively understood but there are still quantitative ambiguities on the dynamics of the fusion mechanism and the predictions need to be assessed. In this communication, we stress the fact that dynamical effects play a crucial role in the amplitude of the reduction of the fusion probability. We found that the fast evolution of the neck degree of freedom affects the slow radial motion, i.e., the fusioning motion, through a dynamical coupling. We showed that we could do a so-called adiabatic elimination of the fast variable in the coupled equation, resulting in an effective one-dimensional equation for the radial motion with a shift of the starting point. This treatment of the dynamical coupling leads to a larger hindrance.