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The Advanced Ion Source for Hadrontherapy (AISHa) is an electron cyclotron resonance ion source operating at 18 GHz, developed at the Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, with the aim of producing high intensity and low emittance highly charged ion beams for hadrontherapy purposes. Moreover, thanks to its unique peculiarities, AISHa is a suitable choice for industrial and scientific applications. In the framework of the INSpIRIT and IRPT projects, in collaboration with the Centro Nazionale di Adroterapia Oncologica, new candidates for cancer treatment are being developed. In particular, the paper presents the results of the commissioning of four ion beams of interest for hadrontherapy: H+, C4+, He2+, and O6+. Their charge state distribution in the best experimental conditions, their emittance, and brightness will be critically discussed, along with the role of ion source tuning and space charge effects in beam transport. Perspectives for further developments will also be presented. [ABSTRACT FROM AUTHOR]

Intense heavy ion beam production with electron cyclotron resonance (ECR) ion sources is a common requirement for many of the accelerators under construction in Europe and elsewhere. An average increase of about one order of magnitude per decade in the performance of ECR ion sources was obtained up to now since the time of pioneering experiment of R. Geller at CEA, Grenoble, and this trend is not deemed to get the saturation at least in the next decade, according to the increased availability of powerful magnets and microwave generators. Electron density above 1013 cm-3 and very high current of multiply charged ions are expected with the use of 28 GHz microwave heating and of an adequate plasma trap, with a B-minimum shape, according to the high B mode concept [S. Gammino and G. Ciavola, Plasma Sources Sci. Technol. 5, 19 (1996)]. The MS-ECRIS ion source has been designed following this concept and its construction is underway at GSI, Darmstadt. The project is the result of the cooperation of nine European institutions with the partial funding of EU through the sixth Framework Programme. The contribution of different institutions has permitted to build in 2006–2007 each component at high level of expertise. The description of the major components will be given in the following with a view on the planning of the assembly and commissioning phase to be carried out in fall 2007. An outline of the experiments to be done with the MS-ECRIS source in the next two years will be presented. [ABSTRACT FROM AUTHOR]

The major infrastructures of nuclear physics in Europe adopted the technology of electron cyclotron resonance (ECR) ion sources for the production of heavy-ion beams. Most of them use 14 GHz electron cyclotron resonance ion sources (ECRISs), except at INFN-LNS, where an 18 GHz superconducting ECRIS is in operation. In the past five years it was demonstrated, in the frame of the EU-FP5 RTD project called “Innovative ECRIS,” that further enhancement of the performances requires a higher frequency (28 GHz and above) and a higher magnetic field (above 2.2 T) for the hexapolar field. Within the EU-FP6 a joint research activity named ISIBHI has been established to build by 2008 two different ion sources, the A-PHOENIX source at LPSC Grenoble, reported in another contribution, and the multipurpose superconducting ECRIS (MS-ECRIS), based on fully superconducting magnets, able to operate in High B mode at a frequency of 28 GHz or higher. Such a development represents a significant step compared to existing devices, and an increase of typically a factor of 10 for the intensity is expected (e.g., 1 emA for medium charge states of heavy ions, or hundreds of eμA of fully stripped light ions, or even 1 eμA of charge states above 50+ for the heaviest species). The challenging issue is the very high level of magnetic field, never achieved by a minimum B trap magnet system; the maximum magnetic field of MS-ECRIS will be higher than 4 or 5 T for the axial field and close to 2.7 T for the hexapolar field. The detailed description of the MS-ECRIS project and of its major constraints will be given along with the general issues of the developments under way. [ABSTRACT FROM AUTHOR]

A series of measurements were carried out with the TRasco Intense Proton Source (TRIPS) to determine the effectiveness of different materials as electron donors. It is well known that the use of boron nitride (BN) disks inside the plasma chamber increases the current extracted from microwave discharge ion sources, generating additional electrons. In the past, one of the two disks was replaced by a 40 μm Al2O3 coating over the extraction electrode, which gave some increase of current, but after less than 200 h was heavily damaged. The tests here reported concern three different options: (a) thicker Al2O3 layer (100 μm) deposited over the extraction electrode; a 1-mm-thick aluminium foil over which an alumina layer is deposited, inserted in the plasma chamber; a 5-mm-thick Al2O3 tube embedded in the plasma chamber of the TRIPS source (the outer diameter of the tube being slightly smaller than the inner diameter of the chamber). The tests were carried out in the same conditions as for magnetic field topology and only rf power and gas input were variable. Special attention was paid to the proton fraction. In fact, a higher proton fraction can be considered as a signature of the higher availability of electrons in the plasma. With the thick alumina tube not only was a better current and proton fraction observed but also a lower beam ripple and better stability. [ABSTRACT FROM AUTHOR]

A study of the design of extraction and transport system for high intensity beams that will be produced by the next generation electron cyclotron resonance ion source (ECRIS) was carried out in the frame of a European collaboration devoted to the definition of the main parameters of third generation ECRIS. High intensity production tests carried out in the previous years at INFN-LNS have shown evidence for the need to review the main concepts of the beam analysis and transport when high currents of low energy highly charged ions are extracted from the source. The transport of such low energy beams becomes critical as soon as the total current exceeds a few mA. The study reported here is based on the calculated parameters for the GyroSERSE source and the computer simulations have been carried out to obtain low emittance beams. The design of the extraction system was carried out by means of the KOBRA (three dimensional) code. The study of the beam line has been carried out with the codes GIOS, GICO, and TRANSPORT by taking into account both the phase space growth due to space charge and to the aberrations inside the magnets. The description of some different beam line options will be also given. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]