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In this paper, a complete three-dimensional (3D) RF model of the cyclotron coaxial resonator—including the coaxial sliding shorts, the “Liner” vacuum chamber, the coupler, the trimmer, and the high RF voltage “Dee” structures—has been developed. An eigenmode analysis was used to simulate the tuning of the resonator in the operating frequency range of 15–48 MHz obtained by two movable sliding shorts and a trimmer. A driven analysis has been performed in order to compute the |S11| parameter (or impedance matching) of the cavity excited by a movable coaxial power coupler. The numerical simulations have been performed using the different peculiarities of two commercial tools, COMSOL Multiphysics and CST microwave studio. Experimental validation of the developed model is presented. The evidence of an unwanted electric field component, orthogonal to the accelerating field, was discovered and a mitigation is also proposed. The impact of the proposed modification was evaluated by using a 3D beam dynamics code under development in the framework of the Superconducting Cyclotron upgrade ongoing at INFN-LNS.

A first prototype of transport beam-line for laser-driven ion beams to be used for the handling of particles accelerated by high-power laser interacting with solid targets has been realized at INFN. The goal is the production of a controlled and stable beam in terms of energy and angular spread. The beam-line consists of two elements: an Energy Selection System (ESS), already realized and characterized with both conventional and laser-accelerated beams, and a Permanent Magnet Quadrupole system (PMQ) designed, in collaboration with SIGMAPHI (Fr), to improve the ESS performances. In this work a description of the ESS system and some results of its characterization with conventional beams are reported, in order to provide a complete explanation of the acceptance calculation. Then, the matching with the PMQ system is presented and, finally, the results of preliminary simulations with a realistic laser-driven energy spectrum are discussed demonstrating the possibility to provide a good quality beam downstream the systems.

The NUMEN project aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of Heavy Ion (HI) induced Double Charge Exchange (DCE) reaction cross sections. In particular, the (18O,18Ne) and (20Ne,20O) reactions are used as tools for β+β+ and β−β− decays, respectively. In the experiments, performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania, the beams are accelerated by the Superconducting Cyclotron (CS) and the reaction ejectiles are detected the MAGNEX magnetic spectrometer. The measured cross sections are challengingly low (a few nb), being the total reaction cross section much larger (a few b), thus a high sensitivity and a large rejection capability are demanded to the experimental set-up. This limits the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, still keeping the high sensitivity of the present set-up, making it feasible a systematic study of all the cases of interest. Frontiers technologies are going to be developed, to this purpose, for the accelerator and the detection systems. In parallel, advanced theoretical models are being developed in order to extract the nuclear structure information from the measured cross sections.

A cheap and efficient diagnostic system for beam monitoring has been recently developed at INFN-LNS in Catania. It consists of a high sensitivity CCD camera detecting the light produced by an ion beam hitting the surface of a scintillating screen and a frame grabber for image acquisition. A scintillating screen, developed at INFN-LNS and consisting of a 2 μm BaF2 layer evaporated on an aluminium plate, has been tested by using (20)Ne and (40)Ar beams in the keV energy range. The CAESAR ECR ion source has been used for investigating the influence of the frequency and magnetic field tuning effects, the impact of the microwave injected power, and of the focusing solenoids along the low energy beam transport on the beam shape and current. These tests will allow to better understand the interplay between the plasma and beam dynamics and, moreover, to improve the transport efficiency along the low energy beam line and the matching with the superconducting cyclotron, particularly relevant in view of the expected upgrade of the machine.

The aim of the EXCYT (EXotics with CYclotron and Tandem) facility is the production and acceleration of radioactive ion beams (RIBs). A primary beam provided by the K-800 superconducting cyclotron will produce, in a target-ion source complex (TIS), the required nuclear species which can be used for low energy experiments (up to 300 keV) or at higher energy by post-accelerating them with the 15 MV tandem. The nuclear experiments programme started in July 2006 with the experiments BIGBANG and RCS using the post-accelerated 8Li ions. Since then 8Li, 9Li and 21Na beams have been already produced and in the near future production of oxygen, fluorine and chlorine beams have been planned, according to the experimental proposals, with beam intensities ranging between 104 to 106 pps and at the typical energies of our tandem.

In the NUMEN Project it is proposed an innovative technique to access the nuclear matrix elements entering in the expression of the life-time of the neutrinoless double beta decay, using relevant cross sections of double charge exchange reactions. A key aspect is the use of MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the INFN Laboratori Nazionali del Sud (LNS) K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams.

The design of a four sector compact superconducting cyclotron, able to accelerate up to 250 A MeV light ions with charge/mass ratio 0.5, is in progress. Light ions like 12 C 6+ , 10 B 5+ , 6 Li 3+ will be extracted by electrostatic deflectors while H 2 + ions can be extracted also by stripping, therefore a beam power of 10 kW or more is available. This cyclotron can be used for radiotherapy with protons or carbon ions and also to drive a facility for production of unusual medical radioisotopes. The main parameters and some features of the machine are here presented.

A superconducting cyclotron accelerating ions up to 250 A MeV, for medical applications and radioactive ions production is being studied at Laboratori Nazionali del Sud in Catania. The radio frequency (RF) system, working in the fourth harmonic, is based on four normal conducting radio frequency cavities operating at 93 MHz. This paper describes an unusual multi-stem cavity design, performed with 3D electromagnetic codes. Our aim is to obtain a cavity, completely housed inside the cyclotron, with a voltage distribution ranging from 65 kV in the injection region to a peak value of 120 kV in the extraction region, and having a low power consumption.

The design of a compact superconducting cyclotron able to deliver light ions with Q/A=0.5 at 250 A MeV is presented. This cyclotron is optimised to accelerate H 2 + molecules to be extracted by stripping. The extraction by stripping allows to extract high beam power to drive a facility of radioactive ion beams. Simultaneously a low intensity beam could be extracted to perform radiotherapy treatment and interdisciplinary research. The main characteristics of the accelerator are presented.

The LNS Superconducting Cyclotron, named “Ciclotrone Superconduttore” (CS), has been in operation for more than 20 years. A wide range of ion species from hydrogen to lead, with energy in the range 10 to 80 AMeV, have been delivered to users. The maximum beam power is limited to 100 W due to the beam dissipation on the electrostatic deflectors. To fulfil the demand of users aiming at studying rare processes in nuclear physics, an upgrade of the cyclotron is necessarily intended to increase the intensity of ion beams with mass lower than 40 a.m.u. up to a power 10 kW. This will be achieved by means of extraction by stripping. This solution needs to replace the cryostat including the superconducting coils. The present capability of the cyclotron will be maintained, i.e. all the ion species allowed by the operating diagram will be available, being extracted by electrostatic extraction. In addition to the high power beams for nuclear physics, it will be possible to produce medical radioisotopes like [Formula: see text] using an internal target.

The design of a mass separator is described for the radioactive ion beam facility at the INFN-LNS in Catania. The two stages of this separator achieve an energy achromatic mass separation, that should allow one to separate the different elements within one isobar as long as their Q β -values are larger than 5 MeV in the case of nuclei of mass 100. The system also incorporates a preseparator that should retain most of the activity produced in the target and ion source.

The aim of the EXCYT project (EXotics with CYclotron and Tandem) is the development of a facility for producing and accelerating exotic beams from 0.2 up to 8 MeV/amu. EXCYT is based on the “two accelerators” method. A K = 800 Superconducting Cyclotron (CS), axially injected by the ECR ion source SERSE, will deliver the primary beam. Such a beam will produce the required nuclear species in a modified ISOLDE type target-source complex. When required, a 15 MV Tandem Van der Graaff will accelerate the secondary beams. Both accelerators are existing and operational at Laboratorio Nazionale del Sud (LNS). Concerning the status of the project, progress has been made in most of the key issues of the project, like the construction of SERSE, cyclotron upgrading, modification of the existing building, high resolution mass separator, and diagnostic equipment for low energy, low intensity beams.

EXCYT, a project for a low energy ISOL facility at LNS, has been funded. It is based on two already existing particle accelerators. A K = 800 superconducting cyclotron will deliver the primary beam of ions A ≤ 48, E = 50–80 MeV/amu. After its interaction in a thick target, the negatively ionized radioactive products (A < 80) will be post-accelerated to 0.2–8 MeV/amu by a 15MV SMP tandem. A description of the facility, including the fully redesigned ion optics, an overview of the design problems and the expected secondary beam intensities are presented.

An innovative technique to access the nuclear matrix elements entering the expression of the life time of the double beta decay by relevant cross section measurements of double charge exchange reactions is proposed. A key aspect of the project is the use of the MAGNEX large acceptance magnetic spectrometer, for the detection of the ejectiles, and of the LNS K800 Superconducting Cyclotron (CS), for the acceleration of the required high resolution and low emittance heavy-ion beams, already in operation at INFN Laboratory Nazionali del Sud in Catania (Italy). However, a major upgrade is foreseen for the INFN-LNS research infrastructure to cope with beam currents as high as several ppA required by the project.

The Laboratorio Nazionale del Sud (LNS) of Catania is equipped with an upgraded 15 MV SMP tandem that is going to be coupled to a k = 800 supercond

This paper describes the beam flux monitoring system that has been developed at the Superconducting Cyclotron at INFN-LNS (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Catania, Italy) in order to monitor the beam parameters such as energy, flux, beam profile, for SEE (Single Event Effects) cross-sections determination and DD (Displacement Damage) studies. In order to have an accurate and continuous monitoring of beam parameters we have developed fully automatic dosimetry setup to be used during SEE (with heavy ions) and DD (with protons up to 60 MeV) tests of electronic devices and systems. The final goal of our activity is to demonstrate that the operation of such a system in air is not detrimental to the accuracy on controlling the beam profile, energy and fluence delivered onto the DUT (Device Under Test) surface, even with non relativistic heavy ions. We have tested our beam monitoring system with the “Reference SEU monitor” developed by ESA/ESTEC, the results are discussed here.

Laser-based accelerators are gaining interest in recent years as an alternative to conventional machines [1]. Nowadays, energy and angular spread of the laser-driven beams are the main issues in application and different solutions for dedicated beam-transport lines have been proposed [2,3]. In this context a system of permanent magnet quadrupoles (PMQs) is going to be realized by INFN [2] researchers, in collaboration with SIGMAPHI [3] company in France, to be used as a collection and pre-selection system for laser driven proton beams. The definition of well specified characteristics, both in terms of performances and field quality, of the magnetic lenses is crucial for the system realization, for an accurate study of the beam dynamics and the proper matching with a magnetic selection system already realized [6,7]. Hence, different series of simulations have been used for studying the PMQs harmonic contents and stating the mechanical and magnetic tolerances in order to have reasonable good beam quality downstream the system. In this paper is reported the method used for the analysis of the PMQs errors and its validation. Also a preliminary optics characterization is presented in which are compared the effects of an ideal PMQs system with a perturbed system on a monochromatic proton beams.

At the Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud (INFN-LNS) in Catania, Italy, the first Italian protontherapy facility, named Centro di AdroTerapia e Applicazioni Nucleari Avanzate (CATANA) has been built in collaboration with the University of Catania. It is based on the use of the 62-MeV proton beam delivered by the K=800 Superconducting Cyclotron installed and working at INFN-LNS since 1995. The facility is mainly devoted to the treatment of ocular diseases like uveal melanoma. A beam treatment line in air has been assembled together with a dedicated positioning patient system. The facility has been in operation since the beginning of 2002 and 66 patients have been successfully treated up to now. The main features of CATANA together with the clinical and dosimetric features will be extensively described; particularly, the proton beam line, that has been entirely built at LNS, with all its elements, the experimental transversal and depth dose distributions of the 62-MeV proton beam obtained for a final collimator of 25-mm diameter and the experimental depth dose distributions of a modulated proton beam obtained for the same final collimator. Finally, the clinical results over 1 yr of treatments, describing the features of the treated diseases will be reported.

The EXCYT facility (EXotics with CYclotron and Tandem) at the INFN‐LNS is based on a K‐800 Superconducting Cyclotron injecting stable heavy‐ion beams (up to 80 MeV/amu, 1 eμA) into a target‐ion source assembly to produce the required nuclear species, and on a 15 MV Tandem for post‐accelerating the radioactive beams. Since December 1999 the Superconducting Cyclotron operates in a stand‐alone mode by means of the new axial injection beam line. The primary beam line has been already mounted and tested. The part of mass separator on the two high‐voltage platforms together with low intensity diagnostics is already installed while the ancillary items along with the part of mass separator at ground potential will be installed during the next stop of accelerator operations. The target‐ion source unit has been successfully tested on‐line at GANIL. The goal of such efforts will be represented by the test of the mass separator with stable beams planned at LNS by the end of the year. The commissioning of the EXCYT fa...

The EXCYT project at LNS, Catania, Italy aims for the production of radioactive ion beams to be accelerated by a tandem up to 8 MeV/amu. The primary beam coming from an ECR ion source goes into a K800 cyclotron and then to the target-ion source assembly. Here the species of interest are produced mainly by projectile fragmentation in a target thicker than the projectile range. The products diffuse through the heated target, are desorbed from its surface and go to the ion source via a transfer line. After ionization, the products are mass-separated and injected into the tandem to be post-accelerated and delivered to the users. It is worth noting that besides the post acceleration there is also an option to supply 300 keV beams for low energy experiments. In the following, the status of the project will be described in detail.

Radioactive ion beams are produced at INFN- Laboratori Nazionali del Sud (LNS) by means of the two operating accelerators, the Tandem and the Superconducting Cyclotron (CS), originally designed to accelerate stable beams. Both the ISOL (Isotope Separation On Line) and the IFF (In-Flight Fragmentation) methods are exploited to produce RIBs in two different ways at different energies: in the first case, the Cyclotron is the primary accelerator and the Tandem accelerates the secondary beams, while in the second case radioactive fragments are produced by the Cyclotron beam in a thin target with energies comparable to the primary beam energy. The ISOL facility is named EXCYT (Exotics at the Cyclotron and Tandem) and was commissioned in 2006, when the first radioactive beam (8Li) has been produced. The IFF installation is named FRIBs (in Flight Radioactive Ion Beams), and it has started to produce radioactive beams in 2001, placing a thin target in the extraction beam line of the Cyclotron. The development of both facilities to produce and accelerate radioactive ion beams at LNS, is briefly described, with some details on the future prospects that are presently under consideration or realization.

The EXCYT facility at the INFN-LNS aims to the production of radioactive ion beams to be post-accelerated by a 15 MV Tandem. The primary stable heavy-ion beam (up to 80 MeV/amu, 1 pμA) is supplied by a K-800 Superconducting Cyclotron, which has been operating in a stand-alone mode, by means of the new axial injection beam line, since December, 1999. The magnets of the primary beam line have been aligned and most of the components of the mass separator have been purchased. Different types of Heavy Ion Target–Source (HITS) systems have been built and are here described; in particular, a microwave ion source fully designed and manufactured at LNS has been assembled and successfully tested. Finally, low-intensity beam diagnostics is also ready and reliability tests are under way.

Construction of a composite wall detector to be used with the intermediate energy beams of the LNS Superconducting Cyclotron-the energy resolution for the large area (20*30 cm/sup 2/) plastic scintillator, 2 cm thick, used as energy measurement detector, was measured. This detector is coupled to a Hybrid Photo Diode (HPD), acting as a photoconverter device, by means of a light guide of suitable shape and dimension. Two kind of configurations of the light guide were tested, one with the light guide glued on the smaller surface 2*20 cm/sup 2/, and one with the light guide glued on the larger surface 20*30 cm/sup 2/.

The aim of the EXCYT project is to develop a facility for the production and the acceleration of exotic beams up to 8 MeV/amu. The primary beams shall be provided by the now operational K-800 superconducting cyclotron and the exotic ions will be accelerated by a 15 MV Tandem. We will describe the cyclotron source and its axial injection system, the transfer beam line sending the primary beams onto the target and the target-ion source unit. Also we will describe the planned high resolution isobar separator that should allow to perform either nuclear or astrophysical and material science experiments. This separator consists of a pre-separator and two main stages and should provide an overall mass resolving power up to m/Dm ≈ 20000.