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The LNS Superconducting Cyclotron (CS) has been working for 20 years making available a wide range of ions and energies. Its operational diagram is peculiar and many experiment are performed each year. In the near future a major upgrade is planned. This will allow to overcome the major limitation of the CS, which is the beam power limited at 100 W. In the new version of the CS, the extracted beam power will be increased up to a factor 100. This improvement will be reached adding a new extraction line dedicated to a specific set of light ions and energies extracted by stripping. The new design could affect the beam dynamics strongly. Indeed, the iron yoke penetrations don't respect the three folds symmetry of our cyclotron. This inhomogeneity produces unwanted field harmonics, which have to be reduced as much as possible to avoid beam precession or second order effects. Here the study accomplished to minimize the perturbation of the non-three fold field symmetry using the current sheet approximation (CSA) is presented, along with the state-of-art configuration of the updated cyclotron, Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The NUMEN experiment at INFN-LNS demands an upgrade of the Superconducting Cyclotron (CS) to deliver beam with power up to 10 kW for ions with mass A < 40 amu. To transport these high power beams, it is mandatory to build a new extraction beam line from the CS and to upgrade the existing beam transport lines to maintain the beam losses below 100 W, both in the accelerator room and along the beam transport areas. Moreover, a new fragment in-flight separator will be built to produce radioactive ion beams, but also to perform energy selection of the beam extracted from the cyclotron, to be delivered to the MAGNEX spectrometer with an energy spread below 0.1% FWHM. The use of a 10 kW ion beam implies also to redesign of the beam transport line inside the MAGNEX experimental room to allow the installation of a new large and well shielded beam dump beyond the apparatus.

The design study of a compact superconducting cyclotron for hadrontherapy being carried out at Laboratori Nazionali del Sud (LNS), Catania. This machine is able to accelerate light ions with a charge to mass ratio of 0,5 to a maximum energy of 300 AMeV. Light ions like carbon will be extracted by electrostatic deflectors. The range of 12C at 300 AMeV is 174 mm in water and it is enough to treat all the tumours of the head and neck district. The machine accelerates also the ionised hydrogen molecule H2 + to 250 AMeV, which is exracted by stripping, giving a proton beam with an energy of 250 AMeV. The range in water of proton beam with this energy being 370 mm, allowing the treatments of the whole tumours. The main parameters of the cyclotron and the main beam dynamics features will be presented.

To deliver high intensity proton beams it is proposed to accelerate H/sub 2//sup +/ by cyclotrons and to use the stripping method to extract the beam. The high binding energy of the H/sub 2//sup +/ molecule allows to use very high magnetic fields produced by superconducting magnets even at energies as high as 1 GeV/n. High beam currents are achievable with these cyclotrons as extrapolated from the experimental results obtained by H/sup -/ cyclotrons. The main advantages, i.e. easy operation, high reliability and high conversion efficiency from electrical to beam power are presented.

The LNS K-800 cyclotron has been operated as a booster of the tandem accelerator until 1999. At the beginning of 2000, the axial injection mode was successfully commissioned and since March 2000 the cyclotron has been working in the stand-alone mode. Transmission measurements through the injection line and the central region are in optimum agreement with the design values. The stand-alone operation allows to achieve a better reproducibility of the beam, moreover the performance of the superconducting ECR source SERSE allows for higher energies and higher intensities. Using phase slits, to reduce the phase acceptance of cyclotron, shorter and cleaner beam pulses are delivered to the users. The upper beam current limit deliverable by the cyclotron is being investigated. The proposal to modify the K-800 cyclotron in order to allow for the extraction of beams with power of about 20 kW is presented too.

The Superconducting Cyclotron has started working in the axial injection mode.Until September 1999 it worked as a booster of the Tandem, and the beam was radially injected in the median plane. Now the beam is produced by an ECR source and injected along the axis. Therefore, the Cyclotron has been provided with an inflector and a central region. The design calculations are here presented. The pieces of the axial equipment are shown as manufactured by the company.The inflector and the central region were assembled in December 1999. In January 2000, the first beam in the new mode has been injected, accelerated and extracted.

International audience; After a detailed design study phase (2003-2004), the SPIRAL2 project at GANIL (Caen, France) was officially approved in May 2005, and is now in its phase of construction, with a project group in which many French laboratories (CEA,CNRS) and international partners are participants. The SPIRAL2 facility is composed of a multi-beam driver accelerator (5mA/40Mev deuterons, 5mA/33Mev protons, 1mA/14.5 Mev/u heavy ions), a dedicated building for the production of radioactive ion beams (RIBs), the existing cyclotron CIME for the post acceleration of the RIBs, and new experimental areas. It will deliver high intensity beams for radioactive ion production by the ISOL method (the main process being the fission of a uranium carbide target), and stable heavy ions for nuclear and interdisciplinary physics. A high intensity neutron flux will also be produced for irradiation and time-of-flight experiments. In this paper we describe the various parts of this facility, the results obtained with prototypes of several major components, the status of the construction itself, and the research and development which remains to be done in some domains, including safety aspects.

International audience; The GANIL facility (Caen, France) (Figure 1) is dedicated to the acceleration of heavy ion beams for nuclear physics, atomic physics, radiobiology and material irradiation. The production of radioactive ion beams for nuclear physics studies represents the main part of the activity. Two complementary methods are used: the Isotope Separation On-Line (ISOL, the SPIRAL1 facility) and the In-Flight Separation techniques (IFS). SPIRAL1, the ISOL facilty, is running since 2001, producing and post-accelerating radioactive ion beams. The energy range available goes from 1.2 MeV/A to 25 MeV/A with a compact cyclotron (CIME, K=265). The running mode of this machine will be recalled as well as a review of the operation from 2001 to 2006. A point will be done on the past, present and future projects which allow to continue to develop the capacities of this equipment and to answer the new demands from the physicists, such as new beamlines for low or high energy experiments, new diagnotics of control or the adaptation of an identification system using Silicon, Germanium or plastic detectors in the requirements of the operation evironnement.