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International audience; The high intensity proton injector for the international accelerator Facility for Antiproton and Ion Research located at GSI-Darmstadt in Germany consists of a pulsed 2.45 GHz microwave ion source, a Low Energy Beam Transport (LEBT), and an electrostatic chopper matching the proton beam to the radio frequency quadrupole. The ion source is based on electron cyclotron resonance plasma production and it has to provide a proton beam at 95 keV energy and up to 100 mA current. The LEBT system with two short solenoids each including two magnetic steerers will transport the proton beam into the compact proton linac, accelerating it to the energy of 68 MeV and serving as the injector of the upgraded heavy ion synchrotron (SIS18). This paper describes the commissioning of the proton injector including beam characterization measurements that have been done at CEA/Saclay in France and is currently at the final commissioning stage.

International audience; The CEA at Saclay is in charge of developing and building the ion source and the low energy line of the proton linac of the FAIR (Facility for Antiproton and Ion Research) accelerator complex located at GSI (Darmstadt) in Germany. The FAIR facility will deliver stable and rare isotope beams covering a huge range of intensities and beam energies for experiments in the fields of atomic physics, plasma physics, nuclear physics, hadron physics, nuclear matter physics, material physics, and biophysics. A significant part of the experimental program at FAIR is dedicated to antiproton physics that requires an ultimate number 7 × 1010 cooled pbar/h. The high-intensity proton beam that is necessary for antiproton production will be delivered by a dedicated 75 mA/70 MeV proton linac. A 2.45 GHz microwave ion source will deliver a 100 mA H+ beam pulsed at 4 Hz with an energy of 95 keV. A 2 solenoids low energy beam transport line allows the injection of the proton beam into the radio frequency quadrupole (RFQ) within an acceptance of 0.3π mm mrad (norm. rms). An electrostatic chopper system located between the second solenoid and the RFQ is used to cut the beam macro-pulse from the source to inject 36 μs long beam pulses into the RFQ. At present time, a Ladder-RFQ is under construction at the University of Frankfurt. This article reports the first beam measurements obtained since mid of 2016. Proton beams have been extracted from the ECR ion source and analyzed just after the extraction column on a dedicated diagnostic chamber. Emittance measurements as well as extracted current and species proportion analysis have been performed in different configurations of ion source parameters, such as magnetic field profile, radio frequency power, gas injection, and puller electrode voltage.

The high current ion source with the low energy beam transport (LEBT) will serve as injector into the proton LINAC to provide primary proton beam for the production of antiprotons. The pulsed ion source developed and built in CEA/Saclay operates with a frequency of 2.45 GHz based on ECR plasma production with two coils with 87.5 mT magnetic field necessary for the electron cyclotron resonance. The compact LEBT consists of two solenoids with a maximum magnetic field of 500 mT including two integrated magnetic steerers to adjust the horizontal and vertical beam positions. The total length of the compact LEBT is 2.3 m and was made as short as possible to reduced emittance growth along the beam line. To measure ion beam intensity behind the pentode extraction system, between solenoids and at the end of the beam line, two current transformers and a Faraday cup are installed. To get information about the beam quality and position, the diagnostic chamber with different equipment will be installed between the two solenoids. This article reports the current status of the proton injector for the facility of antiproton and ion research.

During the past two years, a new ECR 2.45 GHz type ion source has been developed especially dedicated to intense light ion injector project like IPHI (Injecteur Proton Haute Intensite), IFMIF (International Fusion Materials Irradiation Facility), to reduce beam emittance at RFQ entrance by shortening the length of the LEBT. This new ALISES concept (Advanced Light Ion Source Extraction System) is based on the use of an additional LEBT short length solenoid very close to the extraction aperture. The fringe field of this new solenoid produces the needed magnetic field to create the ECR resonance in the plasma chamber. Such geometry allows first putting the solenoid at ground potential, while saving space in front of the extraction to move the first LEBT solenoid closer and focus earlier the intense extracted beam. During the commissioning of the source in 2011–2012, ALISES has produced about 20 mA extracted from a 6 mm diameter plasma extraction hole at 23 kV. But the magnetic configuration combined to the new extraction system geometry led to important Penning discharge conditions in the accelerator column. Lots of them have been eliminated by inserting glass pieces between electrodes to modify equipotential lines with unfavorable ExB vacuum zones where particles were produced and trapped. To study Penning discharge location, several 3D calculations have been performed with OPERA-3D/TOSCA code to simulate the possible production and trapping of electrons in the extraction system. The results obtained on different sources already built have shown very good agreement with sparks location observed experimentally on electrodes. The simulations results as well as experimental measurements are presented and solutions to prevent possible Penning discharge in future source geometries are established.

Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H(+) beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125 mA D(+) beam at 40 MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14 MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H(+) ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H(+) ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished.

Experiments to investigate the space charge compensation of pulsed high-current heavy ion beams are performed at the GSI ion source text benches with a 4-grid analyzer provided by CEA/Saclay. The technical design of the 4-grid analyzer is revised to verify its functionality for measurements at pulsed high-current heavy ion beams. The experimental investigation of space charge compensation processes is needed to increase the performance and quality of current and future accelerator facilities. Measurements are performed directly downstream a triode extraction system mounted to a multi-cusp ion source at a high-current test bench as well as downstream the post-acceleration system of the high-current test injector (HOSTI) with ion energies up to 120 keV/u for helium and argon. At HOSTI, a cold or hot reflex discharge ion source is used to change the conditions for the measurements. The measurements were performed with helium, argon, and xenon and are presented. Results from measurements with single aperture extraction systems are shown.

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.

International audience; In the frame of the production of radioactive ion beams by isotope separator on line method, a new principle of target/ion-source system has been developed at GANIL to produce multicharged ions of alkalis. The principle consists of a surface ionization source associated to a multicharged electron-cyclotron-resonance ion source (ECRIS) named NANOGAN III [R. Leroy et al., AIP Conf. Proc. 749, 137 (2004)] presently used to produce radioactive ions of gas on Système de Production d'Ions Radioactifs Accélérés en Ligne partie I. The singly charged ions are injected in the multicharged ion source without mass separation, through a very short beam line including several stages of acceleration, focusing, deceleration, and rf injection. The first tests showed a good behavior of the ECRIS with the new rf coupling. A study of the surface ionization source is in progress in order to improve its coupling to the $1^+$ beam line.

Production of radioactive ions has started at GANIL on the SPIRAL facility since 2001 and numerous multicharged radioactive ion beams have been delivered for high energy nuclear experiments. This article makes an overview of the different beams that have been produced. In the mean time, an important R and D research program is continued in oder to produce new species of radioactive elements. A new concept of multicharged radioactive production that couples a monocharged ion source, based on the monolithe concept, to an ecr ion source like nanogan3 is under developments and is described The development of monocharged ion sources with high efficiencies is also motivated by a new big project that is under studies at GANIL : the SPIRAL 2 Project. The goal of this project consists in extending the disponible radioactive ion beams to very heavy elements created with a new method of production : while the spiral 1 facility uses the projectile fragmentation for radioactive nuclei production, the spiral 2 project is based on the fission of a Uranium carbide target induced by a neutron flow created by a high intensity deuton beam. The principle and an overview of the project is presented.Production of radioactive ions has started at GANIL on the SPIRAL facility since 2001 and numerous multicharged radioactive ion beams have been delivered for high energy nuclear experiments. This article makes an overview of the different beams that have been produced. In the mean time, an important R and D research program is continued in oder to produce new species of radioactive elements. A new concept of multicharged radioactive production that couples a monocharged ion source, based on the monolithe concept, to an ecr ion source like nanogan3 is under developments and is described The development of monocharged ion sources with high efficiencies is also motivated by a new big project that is under studies at GANIL : the SPIRAL 2 Project. The goal of this project consists in extending the disponible radioactive ion beams to very heavy elements created with a new method of production : while the spiral 1 facility uses the projectile fragmentation for radioactive nuclei production, the spiral 2 project ...

The cylindrical geometry of the magnetic confinement of the MONO1001 electron cyclotron resonance (ECR) ion source made in GANIL [P. Jardin et al., Rev. Sci. Instrum. 73, 789 (2002)] allows us to measure radial characteristics of the working ECR plasma with helium gas. The physical and the geometrical characteristics of the resonance surface inside the working ECR source have been quantified with the help of a visible light spectrometer. Hence, we have deduced a shape of the electron cyclotron resonance ion sources resonance surface which corresponds closely to our magnetic calculations.

International audience; Two new target-source systems have been realized and used to produce radioactive elements with primary beams of 78Kr (68.5 A MeV) and 36Ar (95 A MeV). The production yields of 73,72Kr, 35,33,32Ar, 30,29P, 31,30S, 34,33,32Cl and of some other condensable elements such as 73,72Br and 73,71Se are presented. The results of the improvements between the two versions of the production system are discussed.

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.

By the 90s, the CEA has undertaken to develop the production of intense light ion beams from unconfined ECR plasma. Today, three sources for IPHI, SPIRAL2, and IFMIF projects (respectively, 100 mA of H(+), 8 mA of D(+), and 140 mA of D(+)) are installed at CEA∕Saclay. In order to improve performances and decrease dimensions of these sources, it is necessary to better understand the mechanisms involved in the production and extraction of particles. As a consequence, theoretical and experimental studies are being carried out. We present a theoretical study based on SOLMAXP, a home-made particle-in-cell code. The aim is to investigate the possibility of reducing the plasma chamber size without loss of beam characteristics. This code has been validated by beam intensity measurements on a permanent magnet based source, producing a proton beam of 30 mA at 40 kV on the test bench BETSI. In order to reduce experimentally the dimensions of plasma chamber, a new source, named ALISES with variable plasma chamber volume, is under assembly.

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.

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.