JINR/FLNR, Dubna
Four heavy ions cyclotrons are in operation at FLNR now. Heavy ion beams used for super heavy elements synthesis, RIB production and application. Plan for seven years accelerator development and operation are presented.
PSI, Villigen
HMI, Berlin
A cyclotron based system for hadron therapy is developed, which allows a phased installation: start with protons and Helium ions and add Carbon ions later. The concept is based on an accelerator system of two coupled cyclotrons. The first cyclotron provides protons or He ions that can be used for the full spectrum of treatments and “low energy” C-ions, with a range of 12.7 cm in water for a subset of tumours and radiobiological experiments. For treatments at all tumor sites with C-ions, the C-ions can be boosted subsequently up to 450 MeV/nucl in a separate sector cyclotron, consisting of six sector magnets with superconducting coils and three RF cavities. First studies of the separate sector cyclotron indicate a relatively robust design with straight forward beam dynamics. This system is smaller than corresponding synchrotrons and possesses the typical advantages for therapy applications of a cyclotron. Present efforts to optimize the design of the superconducting sector magnets indicate that the introduction of a radial gradient in the sector would have many advantages.
CAS/IMP, Lanzhou
Funding: Work supported by NSFC project 10635090.
CSR is a new ion cooler-storage-ring system in IMP, Lanzhou, China, which consists of a main ring (CSRm) and an experimental ring (CSRe) with two previous cyclotrons SFC (K=69) and SSC (K=450) as the injectors. The main construction of CSR was completed in 2005. It was being commissioned in the following two years. In 2008 the main purposes of CSR was focused on the primary 78Kr beam with kinetic energy up to 500MeV/u for precise mass spectroscopy at CSRe at isochronous mode. The cancer therapy phase-II in IMP with 100- 250MeV/u carbon beam from CSRm was tested and 6 patients with tumors in the heads were treated successfully.
CNRS-IN2P3/LPSC, Grenoble
The basic principles of the ECR charge state breeder (CSB) are recalled, special attention is paid to the critical parameters allowing the optimization of the ECR charge breeders characteristics (efficiency yield, charge breeding time, capture potential deltaV). An overview is given on the present ECR charge breeders situation and results worldwide. Possible means to increase the 1+ ion beam capture for light ions is presented. In the context of radioactive environment, possible technological improvements and/or simplifications are suggested to facilitate the maintenance and to reduce the human intervention time in case of a subsystem failure.
ANL, Argonne
Funding: Work supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.
The construction of the Californium Rare Ion Breeder Upgrade (CARIBU), a new radioactive beam facility for the Argonne Tandem Linac Accelerator System (ATLAS), is nearing completion. The facility will use fission fragments from a 1 Ci 252Cf source; thermalized and collected into a low-energy particle beam by a helium gas catcher. In order to reaccelerate these beams, the existing ATLAS ECR1 ion source was redesigned to function as an ECR charge breeder. The helium gas catcher system and the charge breeder are located on separate high voltage platforms. An additional high voltage platform was constructed to accommodate a low charge state stable beam source for charge breeding development work. Thus far the charge breeder has been tested with stable beams of rubidium and cesium achieving charge breeding efficiencies of 5.2% into 85Rb17+ and 2.9% into 133Cs20+.
BNL, Upton
Funding: Work supported under the auspices of the US Department of Energy and the National Aeronautics and Space Administration.
At Brookhaven National Laboratory, a high current Electron Beam Ion Source (EBIS) has been developed as part of a new preinjector that is under construction to replace the Tandem Van de Graaffs as the heavy ion preinjector for the RHIC and NASA experimental programs. This preinjector will produce milliampere-level currents of essentially any ion species, with q/A≥ 1/6, in short pulses, for injection into the Booster synchrotron. In order to produce the required intensities, this EBIS uses a 10A electron gun, and an electron collector designed to handle 300 kW of pulsed electron beam power. The EBIS trap region is 1.5 m long, inside a 5T, 2m long, 8” bore superconducting solenoid. The source is designed to switch ion species on a pulse-to-pulse basis, at a 5 Hz repetition rate. Singly-charged ions of the appropriate species, produced external to the EBIS, are injected into the trap and confined until the desired charge state is reached via stepwise ionization by the electron beam. Ions are then extracted and matched into an RFQ, followed by a short IH Linac, for acceleration to 2 MeV/A, prior to injection into the Booster synchrotron. An overview of the preinjector is presented, along with experimental results from the prototype EBIS, where all essential requirements have already been demonstrated. Design features and status of construction of the final high intensity EBIS is also be presented.
JINR/FLNR, Dubna
At the present time, the activities on creation of the new multi-purpose isochronous cyclotron U400R are carried out at the FLNR, JINR. The isochronous cyclotron U400R is intended for obtaining the beams of the accelerated ions from 4He1+ (A/Z=4, W=27MeV/u) up to 132Xe11+ (A/Z=12, W=3.5MeV/u). The cyclotron magnetic field can be changed from 0.8T to 1.8T and allow the smoothly variation of the ion beam energy at the range ±35% from nominal. The cyclotron RF system keeps up 2 - 6 harmonic modes. The aim of the present work is to investigate the optimal geometry of U400R cyclotron center for the wide range of acceleration regimes. The computation of the beams acceleration is carried out by means of the computer code CENTR.
CERN, Geneva
Electron cooling is central in the preparation of dense bunches of lead beams for the LHC. Ion beam pulses from the Linac3 are transformed into short high-brightness bunches using multi-turn injection, cooling and accumulation in the Low Energy Ion Ring, LEIR. The LEIR cooler was the first of a new generation of coolers utilising high-perveance variable-density electron beams for the cooling and accumulation of heavy ion beams. It was commissioned in 2006 at the same time as the LEIR ring and has since been used to provide lead ions for the commissioning of the LHC injector chain. We report briefly on the status of the LHC ion injector chain and present results of measurements made to check and to better understand the influence of the electron beam size, intensity and density profile on the cooling performance. Future plans to improve the performance of the device will also be presented.
KIRAMS, Seoul
A magnet lattice of the carbon-ion synchrotron was studied for cancer therapy, which requires maximum 400 MeV/u carbon beam, at KIRAMS. In the study, we optimized the magnet lattice configuration to fit into the therapy purpose. Major requirements for the purpose are (1) long extraction time (about 1 second), (2) compact size, and (3) low cost. For the requirement (1), a slow extraction scheme was adopted by the use of third integer resonance. For (2) and (3), we minimized the circumference as 69.6m and a number of the magnet elements as 16 and 20 for bending magnet and quadrupole magnet, respectively. The study was carried out by the use of a simulation codes for beam particle dynamics and optics. A detail of the conceptual lattice design of the carbon-ion synchrotron is described in the paper.
JINR, Dubna
Accelerated 12C ion beams are effectively used for cancer treatment at various medical centers, in particular to treat patients with radio resistant tumors. On the other hand, positron emission tomography is the most effective way of tumor diagnostics. The intensive 11C ion beam could allow both these advantages to be combined. It could be used both for cancer treatment and for on-line positron emission tomography. Formation of a primary radioactive 11C6+ ion beam with the intensity of 1010-1011 pps from the ion source may allow cancer treatment and on-line dose verification. 11C isotope is produced in the nuclear reaction 14N (p,α)11C using the gas target chamber irradiated by a proton beam. If the nitrogen target chamber contains about 5% of hydrogen, approximately 1014 methane molecules 11CH4 can be produced each 20 minutes. The separated radioactive methane can be loaded into an ion source. The methodology and technique of formation of high-intensity radioactive carbon beams were tested in the JINR electron string ion source (ESIS) Krion-2 using usual non radioactive methane. The measured conversion efficiency of methane molecules to carbon ions appeared to be rather high, 15 % for C6+ ions and 25% for C4+ ions. The developed technique of pulsed methane loading and the experimentally obtained conversion efficiency permit obtaining primary radioactive 11C6+ beams at the intensity of 1010 -1011 pps and performing cancer treatment and online dose verification.
INFN/LNL, Legnaro
ITEP, Moscow
The positive ion injector for the PIAVE-ALPI complex consists of an ECR ion source placed on a high voltage platform. A 14.4 GHz ECRIS named Alice, designed and constructed at LNL in the early &##8216;90, reliably delivered gaseous beams to the Superconducting RFQ PIAVE for nuclear physics experiments until 2008. The requests for heavy ion beams of increased current and energy, needed to perform the experiments planned for the next years with the AGATA demonstrator, prompted us to upgrade our injector with a new ECR source capable of higher output beam currents and higher charge states. This activity started in 2008 and was completed at the beginning of 2009. A 14.5 GHz, SUPERNANOGAN type ECRIS built by Pantechnik, was installed in our refurbished high voltage platform in July 2008. The space available for maintenance in the platform was increased and a new lead shielding for X-rays has been set up. The water cooling circuits have been redesigned to deliver different fluxes and inlet pressures to the equipment mounted on the platform (plasma chamber, extraction electrodes, bending dipole and power supply). A new safety system has been implemented in order to cope with new and more demanding safety rules. A lot of attention has been paid to the optimisation of the injection line with new diagnostic devices for beam characterisation (movable slits, emittance measurement tools). Commissioning of the new source and injector with beams has started and first results will be reported.
TU Dresden, Dresden
DREEBIT, Dresden
Siemens AG, Erlangen
Funding: Work supported by the EFRE fund of the EU and by the Freistaat Sachsen (Project Nos. 12321/2000 and 12184/2000) and Siemens AG.
The technical performance of ion sources of the Electron Beam Ion Source (EBIS) type has substantially improved during the last years. This is demonstrated by proof-of-principle experiments which have been done using a room temperature EBIS, a so-called Dresden EBIS-A, which has been in use for several years. A new superconducting EBIS, a so-called Dresden EBIS-SC, has been taken into operation. With the expected higher beam intensities the Dresden EBIS-SC will offer a compact and low-cost solution for applications in particle therapy and will be applicable for synchrotron based solutions (single- or multi-turn injection) as well as other accelerator schemes. It is shown that the introduction of the Dresden EBIS-SC will simplify the injection beam line of medical accelerator facilities.