Charge-changing cross sections of 30 Ne, 32,33 Na with a proton target

The total charge-changing, charge pick-up, and partial charge-changing cross sections of very neutron-rich nuclei ( 30 Ne, 32,33 Na) with a proton target have been measured at ~240A MeV for the first time. We introduced the phenomenological correction factor in Glauber-model calculations for the total charge-changing cross sections with the proton target, and applied it to deduce the proton radii of these nuclei. For 30 Ne and 32 Na, the neutron skin thicknesses of the nuclei were deduced by comparing the proton radii with the matter radii deduced from the interaction cross-section measurements. A significant thick neutron-skin has been observed for the nuclei. We also found that the charge pick-up cross sections are much larger than those in the systematics of stable nuclei.