TRIUMF, Vancouver
DAE/VECC, Calcutta
TRIUMF (Canada) and VECC (India) are planning to each build a 1.3GHz 50MeV/500kW superconducting electron linac as a driver for producing radioactive ion beams through photo-fission. The two institutes have launched a collaboration with the initial goal to design, build and test a 5-10MeV superconducting injector cryomodule capable of accelerating up to 10mA. A testing area is being set-up at TRIUMF to house the electron gun, rf buncher, injector cryomodule, diagnostic station and beam-dump for beam studies. The project will test all critical elements of the final linac; beam halo generation, HOM excitation, LLRF and rf beam loading and cavity and cryomodule design/performance. The scope and status of the project will be described.
TRIUMF, Vancouver
PAVAC, Richmond, B.C.
The ISAC-II heavy ion linear accelerator has been in operation at TRIUMF since 2006. The high beta section of the accelerator, consisting of twenty cavities with optimum beta=0.11, is currently under production and is scheduled for completion in 2009. The cavities are superconducting bulk Niobium two-gap quarter-wave resonators with a frequency of 141 MHz, providing, as a design goal, a voltage gain of Veff=1.08 MV at 7 W power dissipation. Production of the cavities is with a Canadian company, PAVAC Industries of Richmond, B.C. after two prototype cavities were developed, produced and successfully tested. Cavity production details and test results will be presented and discussed.
TRIUMF, Vancouver
LPSC, Grenoble
Most ion sources at ISOL (isotope separation on-line) facilities can produce only singly charged ions but efficient post acceleration requires high charge states. For light ions this can be achieved by stripping after a first moderate acceleration but with heavy ions this is no longer possible and charge state breeding is necessary. The breeder should be able to work at a high efficiency for the required charge state and especially for short-lived radioactive isotopes the process should be fast. For the ISAC facility at TRIUMF an ECRIS charge breeder (14 GHz PHOENIX from Pantechnik) has been chosen as it is well adapted to the continuous mode operation of the accelerator and for radioactive ions there is practically no limit for the beam intensity. After off-line optimization on a test bench the source has been moved on-line to the ISAC facility. Mass separated beams of radioactive ions from the on-line ion sources can be directed into the source. During a first test in fall 2008 a beam of 80Rb14+ was successfully created from 80Rb1+ and accelerated by the ISAC post accelerator. A summary of the results from the test bench and from the on-line commissioning will be presented.
TRIUMF, Vancouver
An energy upgrade in the Radioactive Ion Beam (RIB) facility at ISAC-II will see the installation of 20MV of superconducting heavy ion linac. The addition includes twenty beta=11% bulk niobium quarter wave cavities housed in three cryomodules with six cavities in the first two and eight cavities in the last. Each cavity is specified to add 1MV in accelerating potential corresponding to peak surface fields of ~30MV/m. Transverse focusing is achieved with a 9T superconducting solenoid inside each cryomodule. The first module in the expansion has now been assembled and tested. Developments include a new ball screw tuner, locally produced cavities, modified coupler design and LN2 cryogenic circuits. The new developments are described and the results of the first cold tests are presented.
TRIUMF, Vancouver
SFU, Burnaby, BC
UBC, Vancouver, B.C.
Funding: TRIUMF receives funding via a contribution agreement through the National Research Council of Canada.
For ISAC at TRIUMF, radioactive isotopes are generated with a 500MeV proton beam. The beam power is up to 40kW and can easily melt the delicate target if too tightly focused. We protect this target by closely monitoring the distribution of the incident proton beam. There is a 3-wire scanner monitor installed near the target; these give the vertical profile and the +45 and -45 degree profiles. Our objective is to use these 3 measured projections to find the 2-D density distribution. By implementing the maximum entropy (MENT) algorithm, we have developed a computer program to realize tomographic reconstruction of the beam density distribution. Of particular concern is to make the calculation sufficiently efficient that an operator can obtain the distribution within a few seconds of the scan. As well, we have developed the technique to perform phase space reconstruction, using many wire scans and the calculated transfer matrices between them. In this paper we present details of the computer code and the techniques used to improve noise tolerance and compute efficiency.
MEPhI, Moscow
TRIUMF, Vancouver
The results of 3D multipacting simulation in coaxial superconducting quarter wave cavities of the linear accelerator of heavy ions ISAC-II are presented. The multipacting simulation was done using MultP-M code. Dangerous areas of structure and levels of an accelerating field are revealed. Examples of electrons resonant trajectories are presented. Simulation results are compared with experimental results obtained during several superconducting cavities processing.
TRIUMF, Vancouver
The ISAC facility, located at TRIUMF, first began delivering radioactive ion beams (RIBs) in 1998, added post-accelerated beam capability in 2001, and is regarded as one of the premiere RIB facilities in the world. The existing constraints on RIBs of Z<83 and accelerated beams of A/q<30 with energies limited to 5MeV/u are being addressed. A charge-state booster for RIBs has been commissioned to alleviate the A/q<30 restriction and has successfully delivered multi-charge beams through the ISAC accelerators. The 5MeV/u license limit will be removed once an on-line beam monitor is commissioned, allowing beams of up to 11MeV/u to be delivered presently, and increased to over 20MeV/u when the next accelerator phase is installed. In 2008, an actinide target was used to produce RIBs of Z>82; this successful test was performed on a uranium target with yields measured and radiation safety monitored. A new Beam Delivery group has been formed to integrate all aspects of RIB production, which has led to improved efficiency and greater experimental results. These new capabilities will be presented, showing how 2009 promises to be both an exciting and productive year at ISAC.