JAEA, Ibaraki
KEK, Tsukuba
Tokai Radioactive Ion Accelerator Complex (TRIAC) is an ISOL-based radioactive nuclear beam (RNB) facility, connected to the ISOL in the tandem accelerator at Tokai site of Japan Atomic Energy Agency (JAEA). At JAEA-tandem accelerator facility, we can produce radioactive nuclei by means of proton induced uranium fission, heavy ion fusion or transfer reaction. Since TRIAC was opened for use in 2005, we have provided RNBs of fission products and 8Li. For the production of 8Li, we chose 13C (7Li, 8Li) neutron transfer reaction by 7Li primary beam and a 99% enriched 13C sintered disk target. The release time of Li ions from the 13C sintered target was measured to be 3.2 s. We are developing the RNB of 9Li (T1/2=178 ms) but the long release time caused a significant loss of the beam intensity. A boron nitride target which has fast release of Li is developed for 9Li beam with intensity of 104 ions/s after separation by JAEA-ISOL.
INFN/LNS, Catania
The EXCYT project has successfully come to conclusion at the end of 2006. As a consequence a new facility for production and acceleration of radioactive ion beams is now available at Laboratori Nazionali del Sud, Catania. This facility is based on the ISOL method: in particular the primary beam is delivered by a Superconducting Cyclotron, while the secondary beam is post-accelerated by a Tandem. A low energy radioactive beam is also available at the exit of the pre-injector. The main features of the commissioning of the facility will be described. Details will be given on the characteristics of the diagnostic devices. Future development activities are related both to the operative features of the new facility and to the improvements and upgrading that are planned to be introduced in the near future. All of these subjects will be extensively discussed.
INFN/LNL, Legnaro
INFN/LNS, Catania
SPES (Selective Production of Exotic Species) is an INFN project to develop a Radioactive Ion Beam (RIB) facility as an intermediate step toward EURISOL. The SPES project is part of the INFN Road Map for the Nuclear Physics development in Italy and is supported by LNL and LNS the INFN National Laboratories of Nuclear Physics in Legnaro and Catania. The Laboratori Nazionali di Legnaro (LNL) was chosen as the facility site due to the presence of the PIAVE-ALPI accelerator complex, which will be used as re-accelerator for the RIBs. The SPES project is based on the ISOL method with an UCx Direct Target and makes use of a proton driver of at least 40 MeV energy and 200 microA current. Neutron-rich radioactive beams will be produced by Uranium fission at an expected fission rate in the target in the order of 1013 fissions per second. The key feature of SPES is to provide high intensity and highquality beams of neutron rich nuclei to perform forefront research in nuclear structure, reaction dynamics and interdisciplinary fields like medical, biological and material sciences. The exotic isotopes will be re-accelerated by the ALPI superconducting linac at energies up to 10AMeV for masses in the region of A=130 amu with an expected rate on target of 109 pps.
INFN/LNL, Legnaro
Padova University/Dept. Mech. Eng., Padova
Padova University/Dept. Chem., Padova
Pavia University/Dept. Chem., Pavia
Trento University/Dept. Mech. Eng., Trento
INFN/BO, Bologna
SPES is a facility to be built at National Institute of Nuclear Physics (INFN laboratory, Legnaro, Italy) intended to provide intense neutron-rich Radioactive Ion Beams (RIBs) directly hitting a UCx target with a proton beam of 40 MeV and 0.2 mA; RIBs will be produced according to the ISOL technique and the new idea that characterize the SPES project is the design of the production target: we propose a target configuration capable to keep high the number of fissions, low the power deposition and fast the release of the produced isotopes. In this work we will present the recent results on the R&D activities regarding the multi-foil direct UCx target.
RIKEN, Wako, Saitama
The Radioactive Isotope Beam Factory at RIKEN Nishina Center is a next generation facility which is capable of providing the world’s most intense RI beams over the whole range of atomic masses. Three new ring cyclotrons have been constructed as post-accelerators for the existing facility in order to provide the intense heavy ion beam for the RI beam production by using a in-flight separation method. The beam commissioning of RIBF was started at July 2006 and we succeeded in the first beam extraction from the final booster cyclotron, SRC, by using 345 MeV/nucleon aluminum beam on December 28th 2006. The first uranium beam with energy of 345 MeV/nucleon was extracted from the SRC on March 23rd 2007. Various modifications for equipments and many beam studies were performed in order to improve the transmission efficiency and to gain up the beam intensity. Consequently, the world’s most intense 0.4 pnA 238U beam with energy of 345 MeV/nucleon and 170 pnA 48Ca beam with energy of 345 MeV/nucleon have been provided for experiments.
RIKEN, Wako, Saitama
In 2008, the RIKEN RI-Beam Factory (RIBF) succeeded in providing heavy ion beams of 48Ca and 238U with 170 particle-nano-ampere and 0.4 particle-nano-ampere, respectively, at an energy of 345 MeV/u. The transmission efficiency through the accelerator chain has been signifcantly improved owing to the continuous efforts paid since the first beam in 2006. From the operational point of view, however, the intensity of the uranium beam should be much increased. We have, therefore, constructed a superconducting ECR ion source which is capable of the microwave power of 28 GHz. In order to reduce the space-charge effects, the ion source was installed on the high-voltage terminal of the Cockcroft-Walton pre-injector, where the beam from the source will be directly injected into the heavy-ion linac by skipping the RFQ pre-injector. The test of the ion source on the platform has started recently with an existing microwave source of 18 GHz. This pre-injector will be available in October 2009. We will show further upgrade plan of constructing an alternative injector for the RIBF, consisting of the superconducting ECR ion source, an RFQ, and three DTL tanks. An RFQ linac, which has been originally developed for the ion-implantation application will be reused for the new injector. Modification of the RFQ as well as the design study of the DTL are under progress. The new injector, which will be ready in FY2010, aims at independent operation of the RIBF experiments and super-heavy element synthesis.
ANU, Canberra
Electrostatic accelerator laboratories were the nurseries for the heavy ion physics research of today and the accelerators this research needed. The first conference, of what has evolved into the HIAT series, was the "International Conference on the Technology of Electrostatic Accelerators" hosted by the Daresbury Laboratory in 1973. While some of the founding labs of this series have ceased doing accelerator based physics, electrostatic accelerators still inject beams into present day heavy ion boosters. Electrostatic accelerators also continue to provide beams for nuclear and applied physics in laboratories with and without boosters. The development of electrostatic accelerators remains active and will continue in the next few years. The improvements have been spurred by injection beam requirements of boosters as well as the special transmission and stability needs of accelerator mass spectrometry. The survey of the electrostatic accelerator community presented here, has identified a broad range of improvements and uses as well as future technical directions for electrostatic accelerators.
IFIN-HH, Magurele-Bucharest
The Bucharest FN Tandem Accelerator was put in operation in 1973 and upgraded a first time in 1983 to 9 MV. In the period 2006-2009 a second program of the tandem upgrade was performed aiming to transform this accelerator in a modern and versatile facility for atomic and nuclear physics studies as well as for different applications using accelerated ion beams. The upgrade was achieved by replacing the main components of the tandem by new ones and by adding new components. The old HVEC belt of the Van de Graaff generator was replaced by a "Pelletron" system, the old inclined field stainless steel electrodes accelerator tubes were replaced by titanium spiral field tubes, the old HICONEX 834 sputter negative ion source was replaced by a new SNICS II sputter source and all old electronic equipment including RMN and Hall probe gauss meters as well as low voltage and high voltage power supplies for the magnets, lenses and ion sources were replaced by new ones. The new equipment added to the tandem consists of a helium negative ion source, a new injector based on a multi-cathode ion source 40 MC-SNICS II for AMS applications, a new GVM, a new pulsing system in the millisecond range and a new chopper and bunching system for pulsing the ion beam in the nanosecond range. Now the tandem is currently operated in very stable conditions up to 9 MV on a basis of about 4000 hours/year accelerating a broad range of ion species.
BARC, Mumbai
The 14 UD Pelletron Accelerator Facility at Mumbai has recently completed two decades of successful operation. The accelerator is mainly used for basic research in the fields of nuclear, atomic and condensed matter physics as well as material science. The application areas include accelerator mass spectrometry, production of track-etch membranes, radioisotopes production, radiation damage studies and secondary neutron production for cross section measurement etc. Over the years, a number of developmental activities have been carried out in-house that have helped in improving the overall performance and uptime of the accelerator and also made possible to initiate variety of application oriented programmes. Recently, a superconducting LINAC booster has been fully commissioned to provide beams up to A~60 region with E~5 MeV/A. As part of Facility augmentation program, it is planned to have an alternate injector system to the LINAC booster, consisting of 18 GHz superconducting ECR ion source, 75 MHz room temperature RFQ linac and superconducting low-beta resonator cavities. The development of an alternate injector will further enhance the utilization capability of LINAC by covering heavier mass range up to Uranium. The ECR source is being configured jointly with M/s Pantechnik, France, which will deliver a variety of ion beams with high charge states up to 238U34+. This paper will provide detailed presentation of developments being carried out at this facility.
MLL/TU, München
The Tandem accelerator of the Maier-Leibnitz-Laboratorium (MLL), the former "Beschleunigerlabor der LMU und TU München“ was running very reliable during the last years. The status of the Tandem accelerator will be presented and some technical problems of the past years of operation will be discussed. The MAFF project (Munich Accelerator for Fission Fragments) was suspended due to missing funding. MAFF was planned be the successor of the Tandem accelerator. In the next years the Tandem accelerator will be useful for experiments in the framework of the two clusters of excellence “Origin and Structure of the Universe” and MAP (Munich Centre for Advanced Photonics). The Tandem ion beams are applied for experiments in the field of nuclear astrophysics, AMS with astrophysical implication, for irradiation of cells, tissue and finally animals for cancer therapy studies.
LBNL, Berkeley
Notre Dame University, Notre Dame
Funding: This work was supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The DIANA project (Dakota Ion Accelerators for Nuclear Astrophysics) is a collaboration between the University of Notre Dame, University of North Carolina, Western Michigan University, and Lawrence Berkeley National Laboratory to build a nuclear astrophysics accelerator facility 1.4 km below ground. DIANA is part of the US proposal DUSEL (Deep Underground Science and Engineering Laboratory) to establish a crossdisciplinary underground laboratory in the former gold mine of Homestake in South Dakota, USA. DIANA would consist of two high-current accelerators, a 30 to 400 kV variable, high-voltage platform, and a second, dynamitron accelerator with a voltage range of 350 kV to 3 MV. As a unique feature, both accelerators are planned to be equipped with either high-current microwave ion sources or multi-charged ECR ion sources producing ions from protons to oxygen. Electrostatic quadrupole transport elements will be incorporated in the dynamitron high voltage column. Compared to current astrophysics facilities, DIANA could increase the available beam densities on target by magnitudes: up to 100 mA on the low energy accelerator and several mA on the high energy accelerator. An integral part of the DIANA project is the development of a high-density super-sonic gas-jet target which can handle these anticipated beam powers. The paper will explain the main components of the DIANA accelerators and their beam transport lines and will discuss related technical challenges.
UTTAC University of Tsukuba, Tsukuba
KEK/RSC, Tsukuba
Tokyo University/MALT, Tokyo
Funding: Work supported by Grants-in-Aid for Scientific Research Programs of the Ministry of Education, Culture, Sports, Science and Technology, Japan.
The 12UD Pelletron tandem accelerator was installed at the University of Tsukuba in 1975. In recent years, the main research field of the 12UD Pelletron tandem accelerator has shifted to accelerator mass spectrometry (AMS) research from nuclear physics. AMS is an ultrasensitive technique for the study of long-lived radioisotopes, and stable isotopes at very low abundances. The high terminal voltage is an advantage in the detection of heavy radioisotopes. It is important for sensitive measurements of heavy radioisotopes that background interference of their stable isobars are suppressed by AMS measurements. With the multi-nuclide AMS system at the University of Tsukuba (Tsukuba AMS system), we are able to measure long-lived radioisotopes of 14C, 26Al, 36Cl and 129I by employing a molecular pilot beam method that stabilize the terminal voltage with 0.1% accuracy. Much progress has been made in the development of new AMS techniques for the Tsukuba AMS system. As for 36Cl AMS, 36Cl9+ at 100 MeV is used for AMS measurements. The standard deviation of the fluctuation is typically ± 2%, and the machine background level of 36Cl/Cl is lower than 1 × 10-15. This report presents the overview and progress of the Tsukuba AMS system.
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.
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.
Osaka University/RCNP, Osaka
The Research Center for Nuclear Physics (RCNP) cyclotron cascade system has been operated to provide high quality beams for various experiments. In order to increase the physics opportunities, the Azimuthally Varying Field (AVF) cyclotron facility was upgraded recently. A flat-topping system and an 18-GHz superconducting Electron Cyclotron Resonance (ECR) ion source were introduced to improve the beam’s quality and intensity. A new beam line was installed to diagnose the characteristics of the beam to be injected into the ring cyclotron and to bypass the ring cyclotron and directly transport low energy beams from the AVF cyclotron to experimental halls. A separator is equipped to provide RI beams produced by fusion reactions at low energy and by projectile fragmentations at high energy. Development has continued to realize the designed performance of these systems.
RIKEN, Wako
At RIKEN RIB-factory (RIBF) an accelerator complex as an energy booster which consists of superconducting ring cyclotron (SRC), intermediate-stage ring cyclotron (IRC) and fixed-frequency ring cyclotron (FRC) provides very heavy ion beams like uranium with an energy of 345 MeV/u. The total beam power obtained up to now at the SRC is as high as 3 kW in the case of 48Ca with an intensity of 170 pnA. Recently we have succeeded in achieving stable and reliable operation of rf system for new cyclotrons. In this paper the present performance of the rf system and a recent development is reported.
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.
INFN/LNS, Catania
Catania University/Dept. Phys. and Eng., Catania
The study of the Superconducting Cyclotron named SCENT300 was carried out by the accelerator R&D team of Laboratori Nazionali del Sud (LNS-INFN) of Catania in collaboration with the University of Catania and supported by IBA (Belgium). Combining the compactness of a superconducting cyclotron, with the advantage of this kind of machine as its continuous beam and its very good current control, the accelerator R&D group of LNS, by its ten-year of experience with this kind of machine, has developed a concept for a multiparticle therapy cyclotron which is described in the following report.
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.
MPI-K, Heidelberg
Several experiments at the heavy ion storage ring TSR have shown the feasibility of wide range, efficient acceleration and deceleration. The newly developed method of mass selective acceleration enables an effective separation of ion species with relative mass differences of ∆m/m = 3.7 · 10-4. Parabola shaped short bunch lengths were measured for an electron cooled 50 MeV 12C6+ ion beam in the space charge limit. To overcome the space charge limit the TSR was operated at a momentum compaction of α = 1.57.
NIRS, Chiba-shi
Heavy-ion beams have attractive growing interest for cancer treatment owing to their high dose localization at the Bragg peak as well as high biological effect there. Recently, therefore, heavy-ion cancer treatments have been successfully carried out at various facilities and several construction projects for the facility of the heavy-ion therapy have also been progressing in the world, based on the development of accelerator technologies.
ETH/Ion Beam Physics Laboratory, Zürich
Accelerator Mass Spectrometry (AMS) provides instrumentation originally developed by nuclear physicists more than 30 years ago to measure long lived cosmogenic radionuclides such as 10Be, 14C, 26Al, 36Cl, 41Ca, 129I, U, Pu and Pa at natural levels. In the past ten years impressive progress in the measurement technique has been made and with the appearance of compact low energy radiocarbon AMS systems, a new category of AMS instruments has been introduced. This has resulted in a boom of new AMS facilities with more than 20 new installations over the last five years. But low energy AMS is not limited to radiocarbon only and there is a great potential for 10Be, 26Al, 129I and actinides measurements at compact AMS systems. The latest developments towards the low energy limit of AMS resulted in two new types of systems, the NEC Single Stage AMS (SSAMS) and ETH mini carbon dating system (MICADAS) operating with terminal voltages of about 200 kV only. In addition, systems like the HVEE 1 MV Tandetron or the compact ETH 600 kV system are capable to extent the range of applications at compact systems beyond radiocarbon. These systems will have enormous impact, not only on the use of AMS in biomedical research and on radiocarbon dating but also for research applications with 10Be, 26Al, 129I and actinides.
INFN/PG, Perugia
ESA-ESTEC, Noordwijk
INFN/LNS, Catania
MapRad, Perugia
Abant Izzet Baysal Üniversitesi, Bolu
ODTU/Phys. Dept., Ankara
This paper describes the beam monitoring system that has been developed at the Superconducting Cyclotron at INFN-LNS (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Catania, Italy) in order to monitor the beam parameters such as energy, flux, beam profile, for SEE (Single Event Effects) cross-sections determination and DD (Displacement Damage) studies. In order to have an accurate and continuous monitoring of beam parameters we have developed fully automatic dosimetry setup to be used during SEE (with heavy ions) and DD (with protons of 60 MeV/n) tests of electronic devices and systems. The final goal of our activity is to demonstrate how operating in air, which in our experience is easier than in vacuum, is not detrimental to the accuracy on controlling the beam profile, energy and fluence delivered onto the DUT (Device Under Test) surface, even with non relativistic heavy ions. We have exposed during the same session, two beam calibration systems, the "Reference SEU monitor" developed by ESA/ESTEC and the beam monitoring and dosimetry setup developed by our group. The results are compared and discussed here.
RIKEN, Wako
A highly sensitive beam current monitor with an HTS (High-Temperature Superconducting) SQUID (Superconducting QUantum Interference Device) and an HTS current sensor, that is, an HTS SQUID monitor, has been developed for use of the RIBF (RI beam factory) at RIKEN. Unlike other existing facilities, the HTS SQUID monitor allows us to measure the DC of high-energy heavy-ion beams nondestructively in real time, and the beam current extracted from the cyclotron can be recorded without interrupting the beam user's experiments. Both the HTS magnetic shield and the HTS current sensor were dip-coated to form a Bi2 - Sr2 - Ca2 - Cu3 - Ox (Bi-2223) layer on 99.9 % MgO ceramic substrates. In the present work, all the fabricated HTS devices are cooled by a low-vibration pulse-tube refrigerator. These technologies enabled us to downsize the system. Prior to practical use at the RIBF, the HTS-SQUID monitor was installed in the beam transport line of the RIKEN ring cyclotron to demonstrate its performance. As a result, a 20 μA 40Ar15+ beam intensity (63 MeV/u) was successfully measured with a 500 nA resolution. Despite the performance taking place in an environment with strong gamma ray and neutron flux radiations, RF background and large stray magnetic fields, the measurements were successfully carried out in this study. This year, the HTS SQUID monitor was upgraded to have aresolution of 100 nA and was reinstalled inthe beam transport line, enabling us to measure a 4 μA 132Xe20+ (10.8 MeV/u) beam and a 1 μA 132Xe41+ (50.1 MeV/u) beam used for the accelerator operations at RIBF. Hence, we will report the results of the beam measurements an the present status of the HTS SQUID monitor.
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+.
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.
LBNL, Berkeley
Funding: This work was supported by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Nuclear Physics Division of the U.S. Department of Energy under Contract DE AC03-76SF00098.
The development of the superconducting 28 GHz ECR ion source VENUS at the Lawrence Berkeley National Laboratory (LBNL) has pioneered high field superconducting ECR ion sources and opened a path to a new generation of heavy ion accelerators. Because of the success of the VENUS ECR ion source, superconducting 28 GHz ECR ion sources are now key components for proposed radioactive ion beam facilities. This paper will review the recent ion source development program for the VENUS source with a particular focus on the production of high intensity uranium beams. In addition, the paper will discuss a new R&D program started at LBNL to develop ECR ion sources utilizing frequencies higher than 28 GHz. This program addresses the demand for further increases of ion beam intensities for future radioactive ion beam facilities. The most critical technical development required for this new generation of sources is the high-field superconducting magnet system. For instance, the magnetic field strengths necessary for 56 GHz operation produce a peak field in the magnet coils of 12-14 T, requiring new superconductor material such as Nb3Sn. LBNL has recently concluded a conceptual, comparative design analysis of different coil configurations in terms of magnetic performance and has developed a structural support concept compatible with the preferred magnetic design solution. This design effort concludes that a sextupole-in-solenoid ECR magnet structure (VENUS type) is feasible with present Nb3Sn technology, but that an inverted geometry (solenoid-in sextupole) exceeds the capability of Nb3Sn superconductors and can be ruled out as candidate for a 56 GHz ECR ion source.
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.
Goethe Universität Frankfurt/IAP, Frankfurt
MSU/NSCL, East Lansing
ECR and EBIS have become well-known ion sources for most heavy ion accelerator projects. The basic difference arises from the method, how energy is provided to create dense energetic electrons: An ECR uses microwave heating of a magnetically confined plasma, while in an EBIS the energy comes from a power supply to accelerate an electron beam and focus it to high density in a strong solenoidal magnetic field. Basically ECR sources are dc sources of heavy ions but the afterglow extraction also provides intense mA pulses in ms. In contrast to this EBIS sources provide an intense ion pulse in 1-100 μs and therefore find application in feeding synchrotrons. This determines most of the accelerator applications: ECR sources have very successfully extended the range (and life) of cyclotrons, while EBIS has found application at high energy facilities. For radioactive beam facilities, both kind of sources are in use. ECR sources in the trapping mode (ECRIT) perform the ionization (charge breeding) of high intensity primary beams, while EBIS can reach higher charge states at lower emittance, which provides an improved signal to noise ratio for rare isotopes.
Michigan University/MIBL, Ann Arbor
The Michigan Ion Beam Laboratory (MIBL) at the University of Michigan has instruments equipped with ion sources capable of generating a wide variety of ions. The 1.7-MV Tandem accelerator can operate with three different sources: a Torvis source, a Duoplasmatron source and a Sputter source. The 400-kV ion implanter is equipped with a CHORDIS source that can operate in three different modes (gas, sputter, and oven) and is capable of producing ion beams for most of the elements in the periodic table. In this work, we discuss the principle of operation of each source, their performances and the latest applications and projects conducted at MIBL using these sources.
ANL, Argonne
Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.
The ongoing energy upgrade of the heavy-ion linac ATLAS at ANL includes a new cryomodule containing seven 109MHz β=0.15 quarter-wave superconducting cavities to provide an additional 15 MV voltage. Several new features have been incorporated into both the cavity and cryomodule design. For example, the cryomodule separates the cavity vacuum space from the insulating vacuum, a first for TEM cavities. The cavities are designed in order to cancel the beam steering effect due to the RF field. Clean techniques have been applied to achieve low-particulate rf surfaces and are essential for reliable long-term high-gradient operation. The sealed clean subassembly consisting of cavities, beam spools, beam valves, couplers, vacuum manifold, and support frame has been attached to the top plate of the cryomodule outside the clean room. Initial commissioning results are presented. The module was designed and built as a prototype for the Facility for Rare Isotope Beams (FRIB) driver linac, however, a similar design can be effectively used in the front-end of SC proton linacs based on TEM-class SC cavities.
TRIUMF, Vancouver
ISAC is the TRIUMF facility for the production and post acceleration of Rare Isotope Beams (RIBs). The post acceleration section includes two normal conducting linacs, an RFQ injector and a variable energy IH-DTL, and a superconducting linac composed of five cryomodules each containing four quarter wave bulk niobium resonators. All three machines operate CW. The RFQ and DTL deliver beam since 2000 to a medium energy area with energies variable between 150 keV/u and 1.8 MeV/u. The superconducting linac, with an effective voltage of 20 MV started delivering in 2007 with performances exceeding design specifications reaching final energies up to 11 MeV/u for lighter particles. The linac gradients show no average degradation in performance. Well established operational and tuning procedures allow reliable operations. Schemes have been developed to effectively deliver the very low intensity (as low as few hundred particles per second) radioactive ion beams. The superconducting linac will be upgraded with the addition of twenty more cavities (boosting the acceleration voltage to 40 MV) by the end of 2009 making the reliability quest more challenging. In this paper we present past, present and planned operations with the ISAC linacs.
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.
Tokyo Institute of Technology/RIKEN, Tokyo
Tokyo Institute of Technology, Tokyo
Kyushu University, Fukuoka
JAEA, Ibaraki
BNL, Upton
We are investigating space charge dominated beam dynamics in a Radio Frequency Quadrupole (RFQ) linac. In some accelerator systems, desired ions with different charge state ions are simultaneously injected into an RFQ linac. To describe the evolution of the multi charge beam inside the RFQ, we did particle simulation by using Particle-Mesh (PM) method. Here the high-intensity carbon beam made up of C4+, C5+ and C6+ was applied to the simulation (C5+ was set to the designed ion). The space charge contributions to the transverse emittance growth and to the transverse and longitudinal particle motions are presented.
GSI, Darmstadt
HIT, Heidelberg
The Therapy Linac in Heidelberg (HIT) was successfully commissioned in 2006. Required beam parameters were reached except of the beam intensity. The achieved particle transmission for C4+ (design ion) is significantly lower than design. Particle losses are mainly observed in the RFQ. One critical point is the matching section of the RFQ electrodes - Input Radial Matcher (IRM). The original design requires too rigid and narrow beam Twiss-parameters at the RFQ entrance. Also the measured emittance is about twice higher compared to the design. Numerically and experimentally it was proven that the solenoid, used for the beam matching to the RFQ, is not able to provide for the necessary beam size and convergence. As it was shown by beam dynamics simulations using the code DYNAMION, a minor modification of the IRM allows for an improvement of the beam transmission (up to 50%). The proposed measure was realized for an advanced HIT-RFQ-layout, which is recently under test stage. The same modification is already proposed for the linac frontend at Italian Hadrontherapy Center (CNAO, Pavia).
GSI, Darmstadt
The GSI linear accelerator UNILAC and the synchrotron SIS18 will feed the future accelerator facility FAIR (Facility for Antiproton and Ion Research) with heavy ion beams. Several hardware measures at the UNILAC are necessary to meet the FAIR requirement, implicating a beam intensity of 3.2·1011 of U28+-particles within an UNILAC macro pulse of 100μs length and defined emittance space at SIS18 injection. The stripper gas jet density was strongly increased to get the equilibrium charge state even for the heaviest ions. A procedure matching the 6-D-phase space for proper A lvarez DTL injection and increase of the transverse phase advance in the Alvarez accelerators reduces emittance growth. In front of SIS18 injection a new separator provides an immediate selection of the desired charge state after stripping and therefore reduces space charge induced emittance growth. The front-end of the high current injector includes several bottle necks. A compact solenoid channel is planned providing straight line injection into the 4-rod- RFQ. The RFQ will be equipped with new designed electrodes for increased acceptance and reduced emittance growth. The contribution gives an overview of end-to-end simulations, the different upgrade measures, the particular beam investigations, and the status of beam development satisfying FAIR requirements.
MSU/NSCL, East Lansing
GSI, Darmstadt
Goethe Universität Frankfurt/IAP, Frankfurt
Funding: Work supported by the BMBF.
The GSI accelerator facility provides highly charged ion beams up to U92+ at the energy of 400 MeV/u. These are cooled and decelerated down to 4 MeV/u in the Experimental Storage Ring. Within the Heavy Ion Trap facility HITRAP the ions are decelerated further down. The linear decelerator comprises a 108/216 MHz doubledrift- buncher, a 108 MHz-IH-structure, a spiral-type rebuncher, and an RFQ-decelerator with an integrated debuncher providing energy spread reduction. Finally the beam is injected with the energy of 6 keV/u into a Penning trap for final cooling. The decelerator is installed completely and first sections have been successfully commissioned. For commissioning of the individual sections different ion species, e.g. 64Ni28+, 20Ne10+, 197Au79+ were used. Each section was studied with comprehensive beam diagnostics to measure energy, emittance, intensity, transverse profiles, and bunch structure of the beam. The report gives an overview of the beam dynamics, the decelerator structures, and some results of the different commissioning runs.
INFN/LNL, Legnaro
PIAVE-ALPI is the INFN-LNL superconducting heavy ion linac, composed by an SRFQ (superconducting RFQ) section and three QWR sections for a total of 80 cavities installed and an equivalent voltage exceeding 70 MV. In the last years the SRFQ and the bulk niobium QWR came into routine operation, the medium energy QWR section was upgraded with a new Nb sputtered coating, ECR source was firstly improved by using water cooled plasma chamber and then replaced with a new one. The operation of the accelerator complex allowed acquiring a strong experience on many operational issues related to ECRIS, superconducting cavities and cryogenics, beam control and manipulation (with the new and higher accelerating gradient). The paper reports about operational experience, the present limitations and the future perspectives of the facility in view of the experimental campaign with the EU detector AGATA and of the use of PIAVE ALPI as RIB post-accelerator for SPES radioactive ion beam facility.
GSI, Darmstadt
TU Darmstadt, Darmstadt
Funding: Work supported by EURATOM (IFE KiT Program).
The recent development in laser acceleration of protons and ions has stimulated ideas for using this concept as innovative and compact therapy accelerator. While currently achieved parameters do not allow a realistic conceptual study yet we find that our simulation studies on ion collimation and transport, based on output data from the PHELIX experiment, already give a useful guidance. Of particular importance are the chromatic and geometric aberrations of the first collimator as interface between the production target and a conventional accelerator structure. We show that the resulting 6D phase space matches well with the requirements for synchrotron injection.
GSI, Darmstadt
TU Darmstadt, Darmstadt
In this paper, a method for the generation of RF reference signals for synchrotrons and storage rings will be presented. With these reference signals, the RF cavities in the Facility for Antiproton and Ion Research (FAIR) shall be synchronised. Digital frequency generators that work according to the DDS (direct digital synthesis) principle will be used as reference generators. Via an optical network with star topology, these reference generators will be fed with two clock signals that show a certain correlation of frequency and phase. Due to delay measurements, their phases at different end points of the optical network are known. From these clock signals, reference signals with specific frequencies can be derived. The phases of these reference signals can be fine-tuned against the phases of the clock signals, allowing the phases of different reference signals to be synchronised. With the commercially available DDS generators used in the prototype, phase steps of 0.022° are possible. At a reference signal frequency of 50 MHz, this corresponds to 1.22 ps. The presentation describes the functionality of this method for reference signal generation and shows under which conditions the step size of the phase adjustment can be improved further.
GSI, Darmstadt
ITEP, Moscow
In the frame of the FAIR project in spring 2008 an irradiation test of superconducting magnet components was done at GSI Darmstadt. Cave HHD with the beam dump of SIS18 synchrotron was taken as the test area. The beam dump was reequipped to meet the irradiation test requirements. Thereby the first stage of preparation for the irradiation test was to investigate the radiation field around the reconstructed beam dump from the point of view of radiation safety. FLUKA simulations were performed to estimate the dose rate inside and immediate outside of the cave during the irradiation. The simulations showed safe level of the radiation field, and it was later confirmed by the measurements provided by the radiation safety group of GSI.
GSI, Darmstadt
RAS/INR, Moscow
ITEP, Moscow
In spring 2008 an irradiation test of superconducting magnet components was done at GSI Darmstadt in the frame of the FAIR project. Cave HHD with the beam dump of SIS synchrotron was used for irradiation. The irradiation set-up modeled a scenario of beam loss in a FAIR accelerator: U beam with energy of 1 GeV/u was used to irradiate a thin stainless steel bar at very small angle, so that the test samples situated behind the stainless steel bar were exposed to the beam of secondary particles created in the bar. The total number of U ions dumped on the target assembly was about 2·1014. Presently, in spring 2009 some samples are still radioactive. In the paper we present the estimates of the energy deposition and secondary particle fluences in the test samples and also discuss some results of the irradiation campaign.
GSI, Darmstadt
Funding: Work is partially supported by project VEGA 1/0129/09.
In the frame of the FAIR project irradiation test of superconducting magnet components was performed at GSI Darmstadt in May 2008. As a part of the experiment stainless steel samples were irradiated by 1 GeV/u 238U ions. In contrast to the previous experimental studies performed with thick cylindrical samples, the target was a thin plate irradiated at small angle. The target was constituted as a set of individual foils. This stacked-foil target configuration was foreseen for depth-profiling of residual activity. Gamma-ray spectroscopy was used as the main analytical technique. The isotopes with dominating contribution to the residual activity induced in the samples were identified and their contributions were quantified. Depth-profiling of the residual activity of all identified isotopes was performed by measurements of the individual target foils. The characteristic shape of the depth-profiles for the products of target activation and projectile fragments was found and described. Monte Carlo code FLUKA was used for simulations of the residual activity and for estimation of the number of ions delivered to the target and their distribution. The measured data are relevant for assessment of radiation situation at high-energy accelerators during the “hands-on” maintenance as well for assessment of the tolerable beam-losses.
ITEP, Moscow
INFN/LNL, Legnaro
Development of new materials for future energy facilities with higher operating efficiency is a challenging and crucial task. However, full-scale testing of radiation hardness of reactor materials is quite sophisticated and difficult as it requires long session of reactor irradiation; moreover, induced radioactivity considerably complicates further investigation. Ion beam irradiation does not have such a drawback, on the contrary, it has certain advantages. One of them is high speed of defect formation. Therefore, it provides a useful tool for modeling of different radiation damages. Improved understanding of material behavior under high dose irradiation will probably allow to simulate reactor irradiation close to real conditions and to make an adequate estimation of material radiation hardness. Since 2008 in ITEP the ion beam irradiation experiments are under development at the ITEP heavy ion RFQ HIP-1. The main objectives of this work are to study primary damage, cascade formation phenomena, phase stability and self-organization under irradiation. This research is carried out by means of tomographic atom probe and transmission electron microscopy. This linac provides accelerated beams of Cu2+, Fe2+, Cr2+ ions with current up to 10 mA and energy 101 keV/n. The first experiments with ion beam at the linac injector demonstrated promising results. The linac output beam line is now under upgrade. The results of beam extraction line adjustment for experiments with reactor materials are presented. The construction of controllable heated target is presented as well.
NEM, Tokyo
The 1.7 MV tandem accelerator RAPID (Rutherford Backscattering Spectroscopic Analyzer with Particle Induced X-ray Emission and Ion Implantation Devices), the University of Tokyo has been dedicated to various scientific and engineering studies in a wide range of fields by the ion beam analysis availability, including RBS (Rutherford Backscattering Spectroscopy), PIXE (Particle induced X-ray emission) and ion implantation. Total accelerator operation time amounted 9,358 hours since its installation with the highest annual operation time recorded in 2007. RAPID-PIXE analysis system has been contributed to many environmental studies by analyzing elemental composition of water and sediments samples. It is also applied to the analysis of several cultural heritages such as a works of gilded frame from Renaissance in Italy. Recently, the low level ion irradiation system was also developed and applied for the study of CR-39 track detector with proton beam.
KIRAMS, Seoul
Design of conventional 4-vane/rod type of RFQ (Radio Frequency Quadrupole) for the heavy ion medical facility has been studied. The RFQ is capable of accelerating C4+ ions from an initial energy of 10 keV/u to 300 keV/u. In this work, all the design parameters have been optimized to achieve stable structure and compactness. The 3D electromagnetic field distribution and RF analysis were obtained by CST Microwave Studio and the field was used in TOUTATIS for beam simulation. This paper shows the determined physical and mechanical design parameters of RFQ.
CNAO, Milano
GSI, Darmstadt
INFN/LNF, Frascati
INFN/LNL, Legnaro
INFN/LNS, Catania
University of Pavia, Pavia
Politecnico di Milano, Milano
The Centro Nazionale di Adroterapia Oncologica (CNAO) is the Italian centre for deep hadrontherapy, namely an innovative type of radiotherapy using hadrons. The wide range of beam parameters (i.e., energy and intensity) at patient level together with the advantages of hadron-therapy with respect to traditional radio-therapy nourishes the hopes for more effective patient recovery. After the LEBT and the RFQ commissioning, the IH commissioning is now in progress. First patients are expected to be treated in 2010. The present paper summarizes and evaluates the Low Energy Beam Transfer (LEBT) line commissioning, which has been carried out between July 2008 and January 2009.
CNAO, Milano
INFN/LNF, Frascati
The Centro Nazionale di Adroterapia Oncologica (CNAO) is the first Italian center for deep hadrontherapy, namely an innovative type of oncological radiotherapy using hadrons. The CNAO machine installation is in progress and alternates with lines commissioning, started in the Summer 2008. The present paper reports about Beam Diagnostics (BD) choices, status and post-commissioning evaluation, as concerns the Low Energy Beam Transfer (LEBT) line monitors.
LBNL, Berkeley
PPPL, Princeton
LLNL, Livermore
Funding: This work was supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL), a collaboration between Lawrence Berkeley National Laboratory (LBNL), Lawrence Livermore National Laboratory (LLNL), and Princeton Plasma Physics Laboratory (PPPL), is currently constructing a new induction linear accelerator, called Neutralized Drift Compression eXperiment NDCX-II. The accelerator design makes effective use of existing components from LLNL’s decommissioned Advanced Test Accelerator (ATA), especially induction cells and Blumlein voltage sources that have been transferred to LBNL. We have developed an aggressive acceleration “schedule” that compresses the emitted ion pulse from 500 ns to 1 ns in just 15 meters. In the nominal design concept, 30 nC of Li+ are accelerated to 3.5 MeV and allowed to drift-compress to a peak current of about 30 A. That beam will be utilized for warm dense matter experiments investigating the interaction of ion beams with matter at high temperature and pressure. Construction of the accelerator will be complete within a period of approximately two and a half years and will provide a worldwide unique opportunity for ion-driven warm dense matter experiments as well as research related to novel beam manipulations for heavy ion fusion drivers.
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.
JINR, Dubna
Accelerated heavy ions get a charge spectrum on passing a thing target. The charge dispersion and its maximum depend on the ion type, its energy, material, and the foil thickness. Change of the ion charge leads to change of the ion magnetic rigidity. Heavy ion beam extraction from the AVF cyclotrons by stripping in the thing targets is based on loss of the radial stability of the accelerated beam after its magnetic rigidity change. Property data of carbon foils used for the heavy ion beam extraction by stripping are given. Experience of using heavy ion beam extraction from the AVF cyclotrons of FLNR (Dubna) by stripping is considered.
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.
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.
Kyoto University/ICR, Kyoto
JINR, Dubna
NIRS, Chiba-shi
Kyoto University/IAE, Kyoto
MPI-K, Heidelberg
Funding: The present work was supported by Advanced Compact Accelerator Development program by MEXT of Japanese Government. Support from Global COE, The Next Generation of Physics, is also greatly appreciated.
Laser cooling for bunched Mg ion beam with the kinetic energy of 40 keV has been applied with S-LSR at ICR, Kyoto University. Up to now, clear peaking of equilibrium momentum spread after laser cooling has been observed at such a synchrotron tune as resonates with the horizontal betatron tune, which is considered to be due to heat transfer from the horizontal degree of freedom to the longitudinal one. In order to demonstrate transverse cooling by observation of reduction of the horizontal beam size, spontaneous emission from laser induced excited state of the Mg ion, has been observed with the use of CCD camera. Some reduction of horizontal beam size has been observed with a certain synchrotron tune, a little bit smaller compared with the fractional part of the horizontal tune.
JINR, Dubna
The stability of an ion beam in synchrotrons with digital filters in the feedback loop of a transverse damper is treated. Solving the characteristic equation allows to calculate the achievable damping rates as a function of instability growth rate, feedback gain and parameters of the signal processing. A transverse feedback system (TFS) is required in synchrotrons to stabilize the high intensity ion beams against transverse instabilities and to damp the beam injection errors. The TFS damper kicker (DK) corrects the transverse momentum of a bunch in proportion to its displacement from the closed orbit at the location of the beam position monitor (BPM). The digital signal processing unit in the feedback loop between BPM and DK ensures a condition to achieve optimal damping. Transverse Feedback Systems commonly use digital FIR (finite impulse response) and IIR (infinite impulse response) filters for the signal processing. A notch filter is required to remove the closed orbit content of the signal and correct for the imperfect electric centre of the BPM. Further processing is required to adjust for the betatron phase advance between the beam pick-up (BPM) and the damper kicker (DK). Damping rates of the feedback systems with digital notch, Hilbert and all-pass filters are analysed in comparison with those in an ideal feedback system.
IBA, Louvain-la-Neuve
JINR, Dubna
Carbon therapy is most effective method to treat the resistant tumors. A compact superconducting isochronous cyclotron C400 has been designed by IBA-JINR collaboration. This cyclotron will be used for radiotherapy with proton, helium and carbon ions. The 12C6+ and 4He2+ ions will be accelerated to the energy of 400 MeV/amu and will be extracted by electrostatic deflector, H2+ ions will be accelerated to the energy 265 MeV/amu and protons will be extracted by stripping. The magnet yoke has a diameter of 6.6 m, the total weight of the magnet is about 700 t. The designed magnetic field corresponds to 4.5 T in the hills and 2.45 T in the valleys. Superconducting coils will be enclosed in a cryostat; all other parts will be warm. Three external ion sources will be mounted on the switching magnet on the injection line located bellow of the cyclotron. The main parameters of the cyclotron, its design, the current status of development work on the cyclotron systems and simulations of beam dynamic will be presented.
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.
JINR, Dubna
VNIIEF, Sarov
The so-called reflex mode of Electron String Ion Source (ESIS) operation has been under intense study, both experimental and theoretical at JINR during the last decade. The idea of using a tubular electron string ion source (TESIS) has been put forward recently to obtain 1- 2 orders of magnitude increase in the ion output as compared with ESIS. The project is aimed at creating TESIS and studying an electron string in the tubular geometry. The new tubular source with a superconducting solenoid up to 5 T should be constructed in 2010. The method of the off-axis TESIS ion extraction will be used to get TESIS beam emittance comparable with ESIS emittance. It is expected that this new TESIS (Krion T1) will meet all rigid conceptual and technological requirements and should provide an ion output approaching 10 mA of Ar16+ ions in the pulse mode and about 10 μA of Ar16+ ions in the average current mode. Analytical, numerical study of the tubular electron strings and the design of the TESIS construction are given in this report. The experiments with quasi tubular electron beams performed on the modified ESIS Krion 2 are also discussed there.
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.
NSC/KIPT, Kharkov
New properties of vacuum discharges in magnetic field with unconventional discharge gaps at low pressure up to high vacuum are briefly described. Both single- and multi-charge ion sources may be developed on basis of such new discharge modes. Such ion sources may have advantages in comparison with conventional ones. The main advantages are the long lifetime due to the absence of filaments and arc spots, high energy and gas efficiency due to high plasma electron temperature. The development of the discharge research and recent results are discussed.
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.
INFN/LNL, Legnaro
ITEP, Moscow
Singly charged ion sources can easily surpass the 1 kW beam power, as in TRIPS (H+, 60 mA, 80 kV, now installed at LNL) or in NIO1 (H-, 130 mA distributed into 9 beamlets, 60 kV, a project of RFX and INFN-LNL). Beam diagnostic constitutes an important instrument in the high current source development. Even if calorimetric and optical beam profile monitors become possible, still a phase space plot of the beam will be the most useful tool for validation of extraction simulation and for input of subsequent beam transport optimization. Improvements in extraction beam simulations are briefly reported, and effect of space charge neutralization is discussed. Since preliminary design of the traditional two moving slit beam emittance meter show problems with slit deformations and tolerances and with secondary emission, an Allison scanner was chosen with the advantages: only one movement is needed; data acquisition is serial and signal can have an adequate suppression of secondary electrons. The design of a compact Allison scanner head is discussed in detail, showing: 1) the parameter optimization; 2) the segmented construction of electrodes. Experimental commissioning at lower power seems advisable.
CNRS/IN2P3, Strasbourg
This second generation radioactive ion beam facility will be constructed at GANIL and be operational in 2012 with stable beams and 2013 with radioactive ion beams. The aim of the installation is to produce high-intensity, high-quality radioactive ion beams of isotopes from large regions of the chart of nuclei in the range of 3 to 240u. Following description corresponds to the conceptual design study of a low energy RIB transport line for the SPIRAL 2 project.
INFN/BA, Bari
BINP, Novosibirsk
Bari University INFN/BA, Bari
The charge breeding technique is used for Radioactive Ion Beam (RIB) production in the Isotope Separation On Line (ISOL) method in order of optimizing the reacceleration of the radioactive elements produced by a primary beam in a thick target. In some experiments a continuous RIB of certain energy could be required. The EBIS based charge breeding device cannot reach a real CW operation because the high charge state ions produced are extracted by the same part where the 1+ ions are injected, that is, from the electron collector. In this paper, an hollow cathode e-gun for an EBIS in charge breeding operation has been presented. Furthermore, a preliminary system design to inject the 1+ ions from the cathode part will be also shown. In this way, the ions extraction system, placed in the electron beam collector, can be left only to extract the n+ ions, and then the CW operation, at least in principle, could be reached.
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.
IPNO/IN2P3/CNRS, Orsay
GANIL, Caen
JINR, Dubna
Physics that motivated the building of the LISE magnetic spectrometer, main ideas exposed in the scientific council of GANIL June 4th 1981 by M. Brian and M. Fleury, were: atomic physics studies with stripped ions and the study of new isotopes produced by the fragmentation of beams. The LISE line is a doubly achromatic spectrometer (angle and position), with a resolution better than 10-3. Since the first experiment done in 1984, several improvements of the spectrometer were performed: use of a achromatic degrader (1987, used for the first time in the world), building of the achromatic deviation and the Wien Filter (1990), building of a new selection dipole and associated vertical platform (1994), building of the new LISE2000 line (2001), use of the CAVIAR detector (2002), building of the CLIM target (2007). Despite an extreme international competition, the LISE spectrometer remains a world-leader equipment using more than 50 % and up to 90 % of the beam time available at GANIL. This paper presents the status of CAVIAR detector which consists of a MWPC dedicated to in flight particle position at the first dispersive plane of LISE. Since two years, intensive efforts were done with the objective to make available a “plug and play” detector for nuclear physic experiment. We will describe the system from MWPC up to acquisition system. As example few experimental results will be presented.
IPNO/IN2P3/CNRS, Orsay
GANIL, Caen
SACM/IRFU/DSM/CEA, Gif-sur-Yvette
The SPIRAL2 facility at GANIL-Caen is now in its construction phase, with a project group including the participation of many French laboratories (CNRS, CEA) and international partners. The SPIRAL2 facility will be able to produce various accelerated beams at high intensities: 40 MeV Deuterons, 33 MeV Protons with intensity until 5mA and heavy ions with q/A=1/3 up to 14.5MeV/u until 1mA current. We will present the status of the beam dynamics studies recently performed for the high energy beam transport lines of the facility. Various studies were performed on beam-dump concerning beam dynamics, safety and thermo-mechanicals aspects. New experimental areas using stable beams and the cave dedicated to radioactive ion production will be presented according the scientific program.
NIRS, Chiba
Toshiba, Tokyo
Accelerator Engineering Corp., Chiba
A new treatment facility project, as an extension of the existing HIMAC facility, has been initiated for the further development of carbon-ion therapy in NIRS. This new treatment facility will be equipped with a 3D irradiation system with pencil beam scanning. The challenge of this project is to realize treatment of a moving target by scanning irradiation. To accomplish practical moving target irradiation and to fix the final design, a prototype of the scanning irradiation system was constructed and installed into existing HIMAC experiment course. The system and the status of the beam test are described.
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.
NIRS, Chiba
Gunma University, Maebashi
In order to use an intensity-controlled raster scan method at the new treatment facility in HIMAC, we have developed a code system dedicated to the planning of radiotherapy with the scanned 12C beam. Inverse planning techniques are implemented in the software in order to obtain the uniform biological dose distribution within the planned target volume (PTV) as well as reduce the dose delivered to the organ at risks (OARs) delineated on clinical CT images. The scan trajectory is determined so that the path length will be minimized by applying a fast simulated annealing algorithm for scan trajectory optimisation. Furthermore, the extra dose inevitably delivered to the irradiated site during the beam transition time from one spot to the next spot is integrated into the inverse planning process to shorten the treatment time. The code also copes with the planning for intensity modulated ion therapy (IMIT). The reliability of the developed code has been confirmed through the irradiation experiments at the secondary beam line in HIMAC.
CIAE, Beijing
Guangxi University, Nanning
Funding: Supported by National Natural Science Foundation of China (10576040).
A new method was developed for AMS measurement of 126Sn. Major features of the method include the use of SnF2 as target material, the selection of SnF3- molecular ions for extraction form from the target, and the transmission of 126Sn beam current. A sensitivity of (1.92±1.13)×10-10 (126Sn/Sn) has been reached by measuring a blank sample.
CIAE, Beijing
Guangxi University, Nanning
Funding: Work supported by the NSAF (National Nature Science Fundation- China Academy of Engineering Physics Fundation) No.10576040.
236U is a long-lived radioactive isotope with a half-life of 2.342(3) ×107 a, which produced principally by thermal neutron capture on 235U. 236U is potentially applied in geological research and nuclear safeguards. Accelerator mass spectrometry (AMS) is presently the most sensitive technique for the measurement of 236U. A method for AMS measurement of long-lived heavy ion 236U was developed at CIAE with the set up the AMS dedicated injector and the newly proposed 208Pb16O2- molecular ions for the simulation of 236U ion transport. A sensitivity of lower than 10-10 has been achieved for isotopic ratio 236U/238U in present work.