Direct 1 + to n + method for production of radioactive alkaline ions

In the frame of the production of radioactive ion beams by isotope separator on line method, a new principle of target∕ion-source system has been developed at GANIL to produce multicharged ions of alkalis. The principle consists of a surface ionization source associated to a multicharged electron-cyclotron-resonance ion source (ECRIS) named NANOGAN III [ R. Leroy , AIP Conf. Proc. 749 , 137 ( 2004 ) ] presently used to produce radioactive ions of gas on Système de Production d'Ions Radioactifs Accélérés en Ligne partie I. The singly charged ions are injected in the multicharged ion source without mass separation, through a very short beam line including several stages of acceleration, focusing, deceleration, and rf injection. The first tests showed a good behavior of the ECRIS with the new rf coupling. A study of the surface ionization source is in progress in order to improve its coupling to the 1 + beam line.