THE ISOL-MAFIOS SOURCE

ISOL-MAFIOS is a high-efficiency Min B ECRIS charge state breeder for short-lived ISOL beams in the PIAFE project. The ISOL species issuing from a bombarded target are locally ionized (1(+)) in a given ion sour ce (ISOLDE type). They are then accelerated, magnetically selected, an d transported in a long beam line? before being adequately introduced into ISOL-MAFIOS operating in continuous mode. In this system, an ECR plasma (created with a support gas) replaces the usual solid catcher. The ISOL-MAFIOS system captures the (1(+)) ions and transforms them in to (qt) ions. If we call, overall efficiency of ISOL-MAFIOS the ratio of the beam intensities: I(q(+)) after the magnetic selector/I(1(+)) b efore entering in the source, we find for example for Rubidium IRb9+/I Rb1+ approximate to 120 enA/1000 enA and a ratio at least two times la rger for IKr9+/lKr(1-). Moreover, an even more important result of ISO L-MAFIOS is that the release time+ionization time is of the order of 1 0(-2) s instead of many seconds for a solid-state catcher. Thus in the PIAFE project isotopes whose half life times are >10(-2) s become uti lizable for acceleration in the two-cyclotron SARA. Note that in the P IAFE project the (1(+)) ISOL ions are produced by neutron bombardment of a U target inside the high flux reactor ILL and not by the bombardm ent of a target by a primary ion beam. (C) 1996 American Institute of Physics.