Abstract :
Experimental studies of excited states in exotic nuclei populated by direct reactions using secondary RI beam are discussed from the aspects of the inverse kinematics and the selectivity of secondary reactions. Recent studies of γ-ray spectroscopy of low-lying states in N = 8 nucleus 12Be, which reveals disappearance of the p and sd-shell gap, are presented.
For a high-resolution γ-ray spectroscopy, a new array consisting of segmented Ge detectors is developed by CNS. Specifications and preliminary experimental results are introduced.