Reaction Dynamics of Synthesis of Superheavy Elements
阿部 恭久
京都大学基礎物理研究所助教授
日時：2000年12月22日（金） 16:15-18:00
場所：東北大学理学部物理A棟604号室
Recently there is a new wave of experimental developments of synthesis of the superheavy elements. Firstly, a brief review is given of the present status of the experimental and the theoretical studies. Next, a theoretical framework is proposed, based on the compound nucleus theory of reactions, where reaction cross sections are determined by the product of formation and decay (survival)probabilities. Which combination is most favourable is to be determined by the product. Since the statistical theory of decay is well established, most unknown part is the formation, i.e., the fusion probability, which is discussed in detail. In lighter heavy-ion reactions fusion is completely determined by the barrier penetration, but in massive systems, due to the dominating Coulomb force,that is not the end of the story, but a beginning of the new process before the formation of the spherical compound nucleus and its around. Therefore,the fusion is divided into two processes, i.e., the passing-over process and the dynamical evolution to the spherical compound nucleus from the di-nucleus configuration. Discussion,thus, is given on whether the hot fusion path is favorable or the cold one, by taking into account this aspect.
当日16:00より茶菓を用意いたします。