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ACC NIM; International audience; SILHI (High Intensity Light Ion Source) is an ECR ion source producing high intensity proton ordeuteron beams at 95 keV. It is now installed in the IPHI site building, on the CEA/Saclay center. IPHI is a frontend demonstrator of high power accelerator. The source regularly delivers more than 130 mA protons in CWmode and already produced more than 170 mA deuterons in pulsed mode at nominal energy. The last beamcharacterisations, including emittance measurements, space charge compensation analysis and diagnosticimprovements, will be reported. Taking into account the SILHI experience, new developments are in progress tobuild and test a 5 mA deuteron source working in CW mode. This new source will also operate at 2.45 GHz andpermanent magnets will provide the magnetic configuration. This source, of which the design will be discussed,will have to fit in with the SPIRAL 2 accelerator developed at GANIL to produce Radioactive Ion Beams. TheH- test stand status is briefly presented here and detailed in companion papers.This work is partly supported by the European Commission under contract n°: HPRI-CT-2001-50021.

Source of light ions with high intensities The (SILHI) source has been producing proton beams since 1996. The first aim is to produce up to 100 mA cw beams at 95 keV for the injector of protons for high intensity demonstrator. This prototype is developed by a CEA/DSM–CNRS/IN2P3 collaboration for applications such as accelerator driven systems for nuclear waste transmutation, production of radioactive ion beams, or secondary particles. To measure installation reliability, continuous 5 day long runs have been performed. In October 1999, a 99.96% availability was achieved with a single short beam off and a 103 H uninterrupted beam. A new extraction system leads to lower beam losses and higher LEBT transparency. SILHI now produces a 95 keV–130 mA total beam with a proton fraction higher than 80%. Up to a 157 mA (247 mA/cm2) total cw beam has been extracted. The new EPICS control system, electromagnetic interference hardened devices and automatic control procedures now allow us to do longer runs. To analyze th...

A 2.45 GHz electron cyclotron resonance test stand based on a pure volume H− negative ion production is presently running at CEA Saclay. This negative ion source (ECRIN) is working in pulsed mode, up to 10 ms at 10 Hz. Several modifications allowed increasing the extracted H− current from the source. Those results will be summed up in the first part. With the experience collected from this source, a second one using a multi‐cups magnetic structure is under development. Magnetic calculations and simulations showed that an octupolar configuration could allow improving the H− ion production. Those simulations will be discussed and the new set up will also be presented. The source is now being assembled on a new test bench, called BETSI, for light ion source development based on permanent magnet structure.

The frequency ranges of electrical accelerating fields for heavy ion synchrotrons are often very wide. Their dynamics are limited by the physical characteristics of the magnetic load in the resonant structures. We built an accelerating system, with only one gap, using amorphous material, able to replace the two actual MIMAS cavities (the Saturne II booster), in order to make free a part of the ring. The frequency range can be swept at 4 kV. The RF voltage can be increased up to 10 kV, and the frequency to 12 MHz. The geometrical size was chosen to minimize the operation troubles during the cavities permutation on the machine. >

A novel acceleration system for the (simultaneous) application of higher or multiple-harmonics in proton or heavy-ion synchrotrons has been developed for various uses, e.g. the passage of the transition point, applying stochastic cooling on a bunched beam, or for other longitudinal beam manipulations as bunch stretching or compression. The system consists of a coaxial cavity filled with the ferritic amorphous metal VITROVAC of VAC, Hanau, in lieu of the conventional ceramic materials. In its current configuration, it can support a frequency range of 0.2-8 MHz. Amplifier modules for both 10 and 50 kW are available to produce gap voltages in the kV-range. By means of digital synthesis techniques, virtually arbitrary voltage waveforms with harmonic admixtures up to fourth order can routinely be generated at the cavity gap. As illuminating examples we, achieved at high precision a flat-top wave form suitable, e.g. for the transition crossing, a linearized force law at the center of the bucket, and a fourth-order flattened bucket for bunched-beam cooling. The compact cavity system should be well suited for any synchrotron operating in this frequency range. Actual installation of such a system is projected for the medium energy device COSY Julich, and the therapy-oriented ring TERA.

International audience; In France, the Spiral 2 project dedicated to radioactive beam production is based on a 40 MeV continuous wave (cw) deuteron Linac. This installation will allow extending the variety of accelerated particles to very heavy elements. Such beams will open research domains for the GANIL facility. To inject the requested 5 mA deuteron beam into the Spiral 2 Linac, the performance of the high intensity light ion source (SILHI) allowed us to propose such an electron cyclotron resonance source. SILHI, developed at CEA/Saclay, regularly produces high intensity (over 100 mA) proton or deuteron beams through a $\Phi$ 9 mm aperture. So for this project, the main modifications of the source design concern the permanent magnets which provide the axial magnetic configuration and the $\Phi$ 3 mm aperture. The source produced its first beam (proton) in 2004. This article will report the beam characterization while the source produced $D^+$ beam with intensity as high as 7.0 mA. Recently, this permanent magnet source has been equipped with the $\Phi$ 9 mm plasma electrode. So high intensity proton beams reaching more than 100 mA are now extracted from this source.

The high intensity light ion source (SILHI) is the electron cyclotron resonance (ECR) source constructed and tested at CEA-Saclay. The first aim is to produce up to 100 mA cw proton beams at 95 keV for the proton injection high intensity (IPHI) beams [5 MeV radio frequency quadrupole (RFQ) and 10 MeV drift tube linac (DTL)]. This prototype is developed by a CEA–CNRS-IN2P3 collaboration for applications such as accelerator driven systems for nuclear waste transmutation, production of radioactive ion beams or secondary particles. SILHI is also used to study the production of deuteron and H− beams for the International Fusion Material Irradiation Facility and European spallation source projects, respectively. The present status of SILHI and the experiments planned for the near future in both cw and pulsed modes are presented in this article. 80 mA cw proton beams are now currently produced at 95 keV with a high availability (∼1 spark/day). The proton fraction is around 90% and the typical r–r′ rms normalized...