| Co-Investigator(Kenkyū-buntansha) |
SHIMOURA Susumu The University of Tokyo, School of Science, Professor, 大学院・理学系研究科, 教授 (10170995)
KAJINO Toshitaka National Astronomical Observatory of Japan, Division of Theoretical Astronomy, Assistant Professor, 理論研究部, 助教授 (20169444)
MIZUSAKI Takahiro Senshu University, School of Law, Assistant Professor, 法学部, 助教授 (50251400)
HONMA Michio The University of Aizu, The School of Computer Science and Engineering, Lecturer, コンピューター理工学部, 講師 (40264569)
|
|---|
| Research Abstract |
The purpose of this project was to study unknown structure of unstable nudei which are quantum many-body systems, and to explore hidden effects of the nuclear force in nuclei. Moreover we aimed to reveal new many-body mechanisms which may appear in the unstable regions. For these purposes, we performed unified systematic studies of the nuclei in broad regions of the nuclear chart including unstable nuclei, based on the Monte-Carlo Shell Model method and other relevant approaches. We acquired a massive parallel computer system consisting of 232 CPUs for the numerical simulation of a quantum many-body system. The Monte-Carlo Shell Model enables us to perform various calculations which had not yet been made possible by other conventional methods.
As a result, in the region of nuclei whose proton number (Z) is around 10, we found the mechanism which makes the neutron magic number N=20 disappears and a new magic number N=16 emerges. We also evaluated quantitatively how the mechanism affects
… More
the energy spectra and the electromagnetic moments, and provided with the precise predictions of the places where the magic number will be changed. We succeeded in the unified description of the pf shell nuclei, for the first time, evaluating the Gamow-Teller transition strength, and applying it to astrophysics. We have carried out microscopic studies of heavy nuclei whose masses are around 130, performing the theoretical calculation of energy levels, electromagnetic transition probabilities and moments, in good agreement with the experimental values. We also discovered the shell evolution emerged by the tensor force, presenting exotic features of the structure of the unstable nuclei, caused primarily by the shell evolution. Inaddition, much other achievement has been done such as the discovery of the triangular shape of nuclei. So far, 70 original papers have been published.
This project promoted collaborations with many research groups including those outside Japan, and made significant contributions to international conferences including 78 invited talks. With the rapid developments and the diversity of the studied subjects, we employed young physicists, and held an international symposium at the end of the term. Less
|
