The superconductive quarter wave cavities hadron Linac ALPI is the final acceleration stage at the Legnaro National Laboratories. It can accelerate heavy ions from carbon to uranium up to 10 MeV/u for nuclear and applied physics experiments. It is also planned to use it for re-acceleration of the radioactive ion beams for the SPES (Selective Production of Exotic Species) project. The linac was designed in 90’ with the available techniques and it was one of the peak technologies of this kind in Europe at those times. However, the improvements on the cavity fields increased the real-estate gain and the energy output, at the price of lattice periodicity and non-linear RF defocusing. This fact turned out to be troublesome for the operations and delayed the nominal transmission achievement. In this paper we will present the innovative results obtained with swarm intelligence algorithms, in simulations and commissioning. In particular, the increment of the longitudinal acceptance for RIB (Radioactive Ion Beams) acceleration, managing 84 independent cavity phases, and beam orbit correction without the beam first order measurements will be discussed.

LNL heavy ion accelerator complex is based on three main accelerators: Tandem, ALPI and PIAVE. The Tandem XTU is a Van de Graaff accelerator normally operated at terminal voltages of up to about 14 MV. It can be operated in stand–alone mode or as an injector for the linac booster ALPI. The linear accelerator ALPI is built of superconducting resonant cavities and consists of a low–beta branch, particularly important for the acceleration of the heavier mass ions, a medium–beta branch, and a high–beta branch. ALPI can be operated also with the PIAVE injector that consists of a superconducting RFQ and an ECR source. In the last two years, accelerator complex underwent special maintenance to improve its availability and reliability in view of the operation with both Uranium and radioactive beams. In this framework, the main improvements that will be presented will concern Tandem injector and laddertron system, PIAVE ECR source, cryogenic control system and SRFQ tuning system, ALPI low and medium beta design, vacuum control system and new techniques for beam dynamic simulation and commissioning.