GANIL, Caen
The Grand Accélérateur National d’Ions Lourds (GANIL) facility (Caen, France) is dedicated to the acceleration of heavy ion beams for nuclear physics, atomic physics, radiobiology and material irradiation. The production of stable and radioactive ion beams for nuclear physics studies represents the main part of the activity. Two complementary methods are used for exotic beam production: the Isotope Separation On-Line (ISOL, the SPIRAL1 facility) and the In-Flight Separation techniques (IFS). SPIRAL1, the ISOL facility, is running since 2001, producing and post-accelerating radioactive ion beams. The running modes of the accelerators are recalled as well as a review of the operation from 2001 to 2008. A point is done on the way we managed the high intensity ion beam transport issues and constraints which allows the exotic beam production improvement.
JYFL, Jyväskylä
Funding: This work has been supported by the Academy of Finland under the Finnish Centre of Excellence Programme 2006-2011 (Nuclear and Accelerator Based Physics Programme at JYFL).
The accelerator based experiments at JYFL (University of Jyväskylä, Department of Physics) range from basic research in nuclear physics to industrial applications. A substantial share of the beam time hours is allocated for heavy ion beam cocktails, used for irradiation tests of electronics. Producing the required ion beam cocktails has required active development of the JYFL ECR ion sources. This work is briefly discussed together with the implications of the beam cocktail campaign to the beam time allocation procedure. The JYFL ion source group has conducted experiments on plasma physics of ECR ion sources including plasma potential and time-resolved bremsstrahlung measurements, for example. The plasma physics experiments are discussed from the point of view of beam cocktail development.
JYFL, Jyväskylä
Funding: This work has been supported by the Academy of Finland under the Finnish Centre of Excellence Programme 2006-2011 (Nuclear and Accelerator Based Physics Programme at JYFL).
The activities of the JYFL ion source group cover the development of metal ion beams, improvement of beam transmission and studies of Electron Cyclotron Resonance Ion Source (ECRIS) plasma parameters. The development of metal ion beams is one of the most important areas in the accelerator technology. The low energy beam injection for K-130 cyclotron is also studied in order to improve its beam transmission. It has been noticed that the accelerated beam intensity after the cyclotron does not increase with the intensity extracted from the JYFL 14 GHz ECR ion source, which indicates that the beam transmission efficiency decreases remarkably as a function of beam intensity. Three possible explanations have been found: 1) the extraction of the JYFL 14 GHz ECRIS is not optimized for high intensity ion beams, 2) the solenoid focusing in the injection line causes degradation of beam quality and 3) the focusing properties of the dipoles (analysing magnets) are not adequate. In many cases a hollow beam structure is generated while the origin of hollowness remains unknown.
IUAC, New Delhi
A 15 UD Pelletron electrostatic accelerator is in regular operation at Inter-University Accelerator Center (IUAC). It has been providing various ion beams in the energy range from a few tens of MeV to 270MeV for scheduled experiments. A superconducting linac booster module having eight niobium quarter wave resonators has been made operational for boosting the energy of the heavy ion beams from the Pelletron for experiments at higher energies. A new type of high temperature superconducting electron cyclotron resonance ion source (HTS-ECRIS) was designed, fabricated and installed. It is in regular operation as a part of an alternate high current injector (HCI) system being developed for injection of highly charged ions having higher beam current in to the superconducting linac. A radio frequency quadrupole (RFQ) accelerator is being developed to accelerate highly charged particles (A/Q ~ 6) to an energy of 180 keV/A. The beam will then be accelerated further by drift tube linacs (DTLs) to the required velocity for injection of the beams to the linac booster. Details of various developmental activities related to the heavy ion accelerators and associated systems are reported.
GANIL, Caen
In order to provide several kilowatt stable ion beams for radioactive ion beam production, the Grand Accélérateur National d’Ions Lourds (GANIL) upgraded several devices. A High Intensity Transport (THI) safety system has also been studied in 1995 and validated in 1998. By monitoring beam losses all along the cyclotrons and lines and shutting down the beam in case of problem, this system allows accelerating and sending onto targets up to 6kW power beams (instead of 400W in standard mode). Beam losses diagnostics, the associated electronics and software will be depicted (principle, location) as well as the tuning method of the machine to reach step by step the needed power.
Osaka Univ., Suita
An electron cyclotron resonance ion source (ECRIS) has been developing long time and their performance is still extending at present. Recently, they are not only used in producing multi-charged ions, but also molecules and cluster ions. A new type of ion source with a wide operation window is expected for various uses. We developed a novel magnetic field configuration ECRIS. The magnetic field configuration is constructed by a pair of comb-shaped magnetic field by all permanent magnets and has opposite polarity each other with ring-magnets. This magnetic configuration suppresses the loss due to E×B drift, and then plasma confinement is enhanced. We conduct preliminary extracting and forming large bore ion beam from this source. We will make this source a part of tandem type ion source for the first stage. Broad ion beams extracted from the first stage and transfer like a shower to plasma generated by the second stage. We hope to realize a device which has a very wide range operation window in a single device to produce many kinds of ion beams. We try to control plasma parameters by multiply frequency microwaves for broad ion beam extraction. It is found that plasma and beam can be controllable on spatial profiles beyond wide operation window of plasma parameters. We investigated feasibility of the device which has wide range operation window in a single device to produce many kinds of ion beams as like universal source based on ECRIS.
Texas A&M University, College Station
JYFL, Jyväskylä
Texas A&M University is currently configuring a scheme for the production of radioactive-ion beams that incorporates a light-ion guide (LIG) coupled with an ECRIS constructed for charge-boosting (CB-ECRIS). This scheme is part of an upgrade to the Cyclotron Institute and is intended to produce radioactive beams suitable for injection into the K500 superconducting cyclotron. The principle of operation is the following: the primary beam interacts with a production target placed in the gas cell. A continuous flow of helium gas maintains a constant pressure of 500 mbar maximum in the cell. Recoils are thermalized in the helium buffer gas and ejected from the cell within the gas flow through a small exit hole. The positively charged recoil ions (1+ ) are guided into a 2.43 m long rf-only hexapole and will be transported in this manner on-axis into the CB-ECRIS (Charge Breeding - ECRIS). The CB-ECRIS will operate at 14.5 GHz and has been specially constructed by Scientific Solutions of San Diego, California for chargeboosting. An overall image of the entire project will be presented with details on different construction phases. Specific measurements and results will be presented as well as future developments.