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The Trasco Intense Proton Source (TRIPS) was installed at INFN-LNS in May 2000 and has been fully operational since the Fall of 2000; now the source fulfills all the requirements of the TRASCO (Trasmutazione Scorie) project. The proton beam intensity easily exceeds 40 mA at the operating voltage of 80 kV. A set of emittance measurements was carried out for different source conditions and confirmed the simulations performed with the AXCEL code: in all the cases the rms normalized emittance is well lower than the value required for the injection into the RFQ (0.2 π mm mrad); the results will be shown and discussed. Finally a beam reliability of 99.8% has been found during a long run test lasting over 142 h.

With the passing of the years, the need has been growing to be able to build a high current source with a long lifetime. An H− ion production code has been developed to improve the understanding on this ion production. At the same time very promising experimentation is going on at CEA-Saclay on an ECR H− ion source. This code is split in two parts. A PIC 1D MCC 3D code (particle in cell in 1D Monte Carlo with collision in 3D) is in charge of establishing the electron energy distribution function (EEDF), which is later used in a fluid code. This second code calculates the chemistry of the H− ion production. The 2D configuration of the study obliges us to choose a PIC code instead of a Boltzmann one. Two important difficulties are considered. The first one is due to a very low pressure (under 10 mTorr) as it is common in H− production experiments. The second difficulty is to accurately inject the high power discharge (few-tenths kW), usually demanded for such sources. This condition often carries divergence...

Electron cyclotron resonance (ECR) plasma generators have demonstrated their efficiency, reproducibility, and long lifetime for the production of light positive ions like protons or deuterons. These sources generally work in cw mode. A 2.45 GHz ECR test stand based on a pure volume H− ion production is currently under development. This negative ion source is working in pulsed mode, 1 ms at 10 Hz. The first H− ions have been observed at the beginning of 2002 with a poor efficiency. Only a few μA were produced. To avoid negative ions destruction by a nonabsorbed microwave close to the extraction aperture, a stainless steel grid was installed in the rectangular plasma chamber. As a result, the chamber is now effectively separated into two zones: the ECR plasma generator and the H− production zone. By plotting the extracted current versus the production zone length, the H− ion intensity reached more than 100 μA with the grid located 25 mm from the aperture. A voltage difference on the order of 10 V can be app...

The International Fusion Materials Irradiation Facility (IFMIF) linear IFMIF prototype accelerator injector dedicated to high intensity deuteron beam production has been designed, built, and tested at CEA/Saclay between 2008 and 2012. After the completion of the acceptance tests at Saclay, the injector has been fully sent to Japan. The re-assembly of the injector has been performed between March and May 2014. Then after the check-out phase, the production of the first proton beam occurred in November 2014. Hydrogen and deuteron beam commissioning is now in progress after having proceeded with the final tests on the entire injector equipment including high power diagnostics. This article reports the different phases of the injector installation pointing out the safety and security needs, as well as the first beam production results in Japan and chopper tests. Detailed operation and commissioning results (with H(+) and D(+) 100 keV beams) are reported in a second article.

Ion species ratio of high current positive hydrogen/deuterium ion beams extracted from an electron-cyclotron-resonance ion source for International Fusion Materials Irradiation Facility accelerator was measured by the Doppler shift Balmer-α line spectroscopy. The proton (H(+)) ratio at the middle of the low energy beam transport reached 80% at the hydrogen ion beam extraction of 100 keV/160 mA and the deuteron (D(+)) ratio reached 75% at the deuterium ion beam extraction of 100 keV/113 mA. It is found that the H(+) ratio measured by the spectroscopy gives lower than that derived from the phase-space diagram measured by an Allison scanner type emittance monitor. The H(+)/D(+) ratio estimated by the emittance monitor was more than 90% at those extraction currents.

Reliable high intensity H− ion source development is now part of the CEA/Saclay work in the field of high intensity linear accelerators. A 2.45 GHz electron cyclotron resonance (ECR) H− ion source and test bench have been built. This new source has been designed taking into account our experience on the French high intensity ECR proton source. For H− ion production, the high-energy electrons created in the ECR zone are trapped by a dipole magnetic filter. A rectangular 210 mm long plasma chamber and an intermediate iron shield are used to minimize the magnetic field in the extraction region. A second magnetic dipole separates electrons and negative ions in a 10 kV extraction system. To reduce the electron/H− ratio, the plasma electrode is biased by a power supply. The first helium plasma allowed us to verify the satisfactory electron separator behavior. Pulsed hydrogen plasma is currently produced. The first plasma characterization is under progress as a function of ion source parameters by using Langmuir...

The TRASCO project (trasmutazione scorie) is a R&D program whose goal is the design of an accelerator driving system for nuclear waste transmutation. The high current continuous wave proton linear accelerator will drive a subcritical system to transmutate nuclear wastes, while producing energy. The proton source TRIPS is a high intensity microwave source, which should be highly reliable and that should provide a minimum proton current of 50 mA with a r−r′ root mean square normalized emittance lower than 0.2 π mm mrad. A program of cooperation has been entered into with CEA-Saclay, where the IPHI project is in progress and the proton source SILHI has been designed and built using goals close to those of TRIPS. The construction of TRIPS is underway and the first beam is scheduled for the first half of 2000. The main features of this source and the results of the optics calculations are presented.

Time-resolved measurements of the compensation process have been performed at the (high-intensity light ion source)-low-energy beam transport test stand (CEA-Saclay) using an 92 kV; 73 mA proton beam. A residual gas ion energy analyzer was used to measure the potential distribution as a function of time. To measure the radial density profile of the ion beam a charge coupled device camera has been used to perform time-resolved measurements and to estimate the rise time of compensation. Both measurements in combination allow an investigation of the space-charge compensation process due to the residual gas ionization and the experimental study of the rise of compensation. A numerical simulation of selfconsistent equilibrium states [J. Pozimski, Il Nuovo Cimento 106, A.N.11 (1993)] of the ion beam has been used to determine plasma parameters such as the density and the temperature of the electrons from the measured data. An interpretation of the acquired data and the achieved results is given.

A large high current EBIS source, working at room temperature, and using a noncryogenic solenoid, has been completed in Saclay. This source, whose current density is lower (≊100 A cm−2) than the cryogenic EBIS, has been designed to be used at very low pressures with turbo and Ti sublimator pumping. An ultimate vacuum of 8×10−12 mbar has been reached and may be obtained in a few days after opening. This ultrahigh vacuum allows very long confinement times. The electron beam has been injected and large amounts of Ar16+ and Ar17+ ions have been obtained in July. These preliminary results are in good agreement with theoretical simulations. More details about the special dynamics of the warm EBIS are presented.

A 2.45 GHz electron cyclotron resonance (ECR) ion source for producing a 100 mA H+ beam is under study. The microwave power is coupled through a quartz window and a water‐cooled 90° waveguide bend in order to avoid the heating of the electrons backstreaming from the source. The ECR condition is obtained with dc magnetic coils. Preliminary results reported here show that a beam current density of 75 mA/cm2 can be extracted at 10 kV from a 3‐mm‐diam aperture, with 1.2 kW of microwave power at 1×10−3 mbar of hydrogen pressure. The proton fraction is 75% with an alumina‐coated plasma electrode and 85% with a nitride coating.

A hollow cathode ion source (HCIS) has been developed in our Laboratory to produce, by cathodic sputtering in a glow discharge, a one charge metallic ion beam. This source is used as an injector for the electron‐beam ion source (EBIS) Dione that produce, after ion stripping, a highly charged heavy‐ion beam for acceleration in Mimas–Saturne synchrotrons. Due to the good pulse‐to‐pulse repeatability of the HCIS, the very long lifetime of the cathode (several months), as well as the very good value of the normalized emittance (enorm=4×10−9 π mrad), this source appears as an ideal EBIS injector for metallic and gaseous elements. In this paper we report the description of the HCIS and the experimental results achieved, after injection in the EBIS, by the production of heavy‐ion beams like Fe20+, Au50+, and U55+ (from 4×107 to 9×106 ions/cycle).

To avoid saturation, beam current transformers must be shielded from solenoid, quad, and RFQ high stray fields. Good understanding of field distribution, shielding materials, and techniques is required. Space availability imposes compact shields along the beam pipe. This paper describes compact effective concatenated magnetic shields for IFMIF-EVEDA LIPAc LEBT and MEBT and for FAIR Proton Linac injector. They protect the ACCT Current Transformers beyond 37 mT radial external fields. Measurements made at Saclay on the SILHI source are presented.

One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

In the framework of the IFMIF-EVEDA project (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), CEA∕IRFU is in charge of the design, construction, and characterization of the 140 mA continuous deuteron injector, including the source and the low energy beam line. The electron cyclotron resonance ion source which operates at 2.45 GHz is associated with a 4-electrode extraction system in order to minimize beam divergence at the source exit. Krypton gas injection is foreseen in the 2-solenoid low energy beam line. Such Kr injection will allow reaching a high level of space charge compensation in order to improve the beam matching at the radio frequency quadrupole (RFQ) entrance. The injector construction is now completed on the Saclay site and the first plasma and beam production has been produced in May 2011. This installation will be tested with proton and deuteron beams either in pulsed or continuous mode at Saclay before shipping to Japan. In this paper, after a brief description of the installation, the preliminary results obtained with hydrogen gas injection into the plasma chamber will be reported.

In the framework of the International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities (IFMIF-EVEDA) project, CEA/IRFU is in charge of the design and realization of the 140 mA cw deuteron Injector. The electron cyclotron resonance ion source operates at 2.45 GHz and a 4 electrode extraction system has been chosen. A 2 solenoid beam line, together with a high space charge compensation have been optimized for a proper beam injection in the 175 MHz radio frequency quadrupole. The injector will be tested with proton and deuteron beam production either in pulsed mode or in cw mode on the CEA-Saclay site before to be shipped to Japan. Special attention was paid to neutron emission due to (d,D) reaction. In this paper, the general IFMIF Injector design is reported, pointing out beam dynamics, radioprotection, diagnostics, and mechanical aspects.

In the framework of several International HPPA projects (such as IFMIF, IPHI, and Spiral2) the CEA handles the design and the developments of several electron cyclotron resonance (ECR) ion sources. For the IFMIF EVEDA demonstrator, a 140 mA cw extracted deuteron beam will be required for high yield of neutron production. For radioactive ion production in the Spiral2 project, several milliamperes of deuterons will be delivered with a permanent magnet source. The optimization of the beam quality at the entrance of the radio frequency quadropole (RFQ) accelerator system triggered the need of a new test bench for ion source optimization and beam qualification. The BETSI ion source test bench will operate up to 50 kV and ignite cw or pulsed hydrogen plasma with a 2.45 GHz magnetron. Great care has already been taken to design electrostatic optics of the extraction system to minimize the emittance growth. Plasma diagnostics will be inserted in the source chamber and several beam diagnostics (emittance and current measurements, beam species analysis) will also be implemented on the low energy beam line transport (LEBT). These diagnostics allow the simultaneous analysis of the beam quality with the plasma parameters of the source. Regional funding request will also be needed to improve the LEBT for space charge compensation measurements. The design of the present and upgraded test bench will be reported as well as the first extracted beam analysis.

In the framework of the IFMIF-EVEDA phase (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), the CEA-Saclay is in charged of the design and realization of the 140 mA cw deuteron source. The IFMIF EVEDA demonstrator will be installed in Japan in the next six years and will have to accelerate the deuteron beam up to 9 MeV. CEA will build the source and the low energy beam line (LEBT) and will test the cw high intensity deuteron production at Saclay. The SILHI source is an electron cyclotron resonance (ECR) source, operating at 2.45 GHz. In 2001, it produced more than 130 mA of deuteron beam in pulsed mode to minimize neutron production. Such a result pushes to develop a new ECR source based on the SILHI design and equipped with a specific extraction system. Several options of the accelerator column will be implemented in order to improve the reliability and the efficiency of the source. The IFMIF source and LEBT design will be reported.

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.

A 2.45GHz electron cyclotron resonance test stand based on a pure volume H− (negative) ion production is actually under development at CEA Saclay. The negative ion source is working in a pulsed mode, 2ms at 5–10Hz. The first H− ions have been observed at the beginning of 2002 with a poor efficiency: only a few microamperes were produced. Several changes inside the plasma chamber have increased the production rate of negative ions up to several milliamperes. A biased grid separates the plasma chamber into two regions. In the first part, we produce excited H2 molecules that are necessary for producing in the second zone H− ions by a dissociative attachment process located near the extraction zone. Qualitative and quantitative beam diagnostics allow measuring several beam parameters and analyzing the effect of gas mixing or materials on the H− production rate.

The SATURNE synchrotron facility is equipped with an EBIS source for heavy ion nuclear‐physics experiments. SATURNE is accelerating either conventional heavy ions as Kr30+ or polarized 6Li3+ produced in two external ion sources, injected and stripped inside DIONE. In this paper, the DIONE last performances will be given and recent developments as well: evaporative cooling experiments and the main options for a new EBIS project: RHEA.