放射性束物理实验发展现状

Recent development in experimental RIB physics

近年来随着放射性束流装置的发展,对非稳定核的研究取得了一系列的重大进展。重要的物理发现包括滴线区的晕核与增强的集团结构、非稳定核中的壳演化与新幻数、新的有效相互作用、新的集体运动模式、核反应中的多步过程与强耦合效应等。本文着重从实验探测的角度,对非稳定核基态基本物理量的测量、非稳定核的衰变测量、中低能核反应、快速束流及零度谱学等方面做了概述和分析,特别指出他们在非稳定核研究中作用和新发展。

Background： In recent years, along with the development of the radioactive ion beam facilities, much progress has been achieved in studies of unstable nuclei. Main discoveries include exotic halo and cluster structures around the drip lines; shell evolution and new magic numbers in unstable nuclei; new effective interactions such as tensor force, three-body forces, new spin-orbit force; new modes of collective motion such as soft giant dipole resonance; multi-step process and strong couplings in nuclear reaction with unstable nuclei. Purpose： This review is focused mainly on the outline of the experimental methods which has been intensively applied to investigate the new aspects of unstable nuclei. Methods： Recently many new techniques have been used to the measurement of the basic properties of the ground state of unstable nuclei. Decay measurement, nuclear reaction at low and intermediate energies, fast beam and zero-degree spectroscopy are also widely used. The special development of these methods related to the study of unstable nuclei has been emphasized. Results and Conclusion： Plenty new phenomena of unstable nuclei were observed, which greatly expanded our studies on nuclear physics. With the development of facilities and experimental techniques, we may expect new experimental data coming soon, which would refine our knowledge of the nuclear physics.