報告題目: New results on exotic modes of excitation in the A=130 mass region

　　報告人：Prof. Costel Petrache 巴黎十一大 (Université Paris-Sud)

　　報告題目2: Triaxial rotations in Nd-138

　　報告人：石躍 哈爾濱工業(yè)大學(xué)

　　時間：2019年4月19日（星期五）9:30

　　地點：近代物理所工藝樓6樓會議室

　　Abstract

　　New results on exotic modes of excitation in the A=130 mass region

　　C. M. Petrache

　　CSNSM, Universit_e Paris-Sud, CNRS-IN2P3, Universit_e Paris-Saclay, Orsay, France.

　　Contact e-mail: Costel.Petrache@csnsm.in2p3.fr

　　The breaking of symmetries in quantum systems is one of the key issues in nuclear physics. In particular, the spontaneous symmetry breaking in rotating nuclei leads to exotic collective modes, like the chiral motion, which is an unique _ngerprint of triaxiality in nuclei and have been intensively studied in recent years. We are currently involved in the study of Lanthanide nuclei. New results have been obtained recently and interpreted as the manifestation of a stable triaxial nuclear shape, presenting various types of collective motion, like tilted axis and principal axis rotation, chiral motion, rotation of nuclei with oblate shape at very high spins. Chiral bands in even-even nuclei, which were taught to be unfavored energetically, unstable against 3D rotation and di_cult to observe, have been instead identi_ed very recently in 136Nd. Other new experimental results revealing the interplay between order and chaos in hot excited nuclei at very high spin have also been obtained recently. The multiple chiral bands and competing collective oblate rotation up to very high spins in Nd nuclei will be discussed.