Experiments with light neutron-rich projectiles

Experiments using secondary nuclear beams at the BEVALAC showed that light neutron-rich nuclei have interesting properties, such as the large nuclear matter radii (sometimes called a neutron halo) and soft E1 mode, which have not been seen for nuclei near the valley stability. In parallel with the theoretical works, experimentalists continued to study these in more detail by various methods. One direction is performing the experiments at intermediate-energy cyclotrons, such as MSU, GANIL, and RIKEN, where much higher beam intensity can be obtained. Second direction is the spectroscopic study of these nuclei using pions and Fermi-energy heavy ions. After the summary of the results from BEVALAC experiments, the author presents some new directions, such as the elastic scattering of 11Li on hydrogen, exclusive measurement of 11Li+Pb→9Li+n+n for the direct observation of the soft E1 mode, and the spectroscopy of 11Li by pion double-charge-exchange reaction