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.