  The SPIRAL1 charge breeder is now under operation. Radioactive beam has
already been delivered [1] to Physicist for performing experiment. Although
charge breeding efficiencies demonstrated high performances for stable ion
beams, those efficiencies regarding radioactive ion beams were found, in the
first experiments, lower than expected. The beam optics, prior to the injection
of the 1+ ions into the SPIRAL1 charge breeder, is of prime importance [2] for
getting such high efficiencies. Moreover, the intensities of the radioactive
ion beams are so low, that it is really difficult to tune the charge breeder.
The tuning of the charge breeder for radioactive ion beams requires a
particular procedure often referred as blind tuning. A stable beam hav-ing a
close Brho (few percent) is required to find out the set of optic parameters
preceding the tuning of the radioactive beam. Hence, it has been decided to
focus our effort on that procedure as to get control of the 1+ beam optics
leading to high charge breeding efficiencies whatever the 1+ mass, energy and
Target Ion Source System (TISS) used. Being aware that each TISS provide ion
beams with a specific energy spread DeltaE, and given that the acceptance
energy win-dow of the charge breeder is rather narrow; that parameter must play
also an important role in the whole charge breed-ing efficiency.
