Nuclear matter radii may be inferred from total interaction cross sections derived from total-absorption measurements of radioactive ions in thick targets. This technique requires intensities of the order of only one ion/s. For instance, interesting results were obtained by a RIKEN-GSI collaboration [1] by using beams of unstable sodium isotopes. These data, together with isotope-shift measurements, provide a first experimental manifestation of neutron skins. Beam intensities available at the new facility will allow systematic studies of this phenomenon in heavy nuclei. Such experiments can be performed using the high-resolution spectrometer after the dipole magnet.

[1] T. Suzuki et al., Phys. Rev. Lett. 75 (1995) 3241.