Upgrading a Duoplasmatron ion source to produce high brightness beam for nuclear microprobe applications with a tandem accelerator (original) (raw)
Related papers
Review of Scientific Instruments
The Tandetron Laboratory of the Nuclear Physics Institute of the Czech Academy of Sciences is equipped with five beam lines associated with a 3 MV tandem electrostatic accelerator model 4130 MC from High Voltage Engineering Europa B.V. This accelerator is coupled with two duoplasmatron sources and a single sputter ion source and provides ions from hydrogen to gold. One of these lines is a nuclear microbeam facility, utilizing ion beams of micro-and sub-micro sizes for materials research by use of particle induced x-ray emission spectroscopy, particle induced gamma emission, Rutherford back-scattering spectroscopy, and scanning transmission ion microscopy methods as well as for ion beam writing. The major advantage of the presented microprobe is a possibility of 3D structure creation not only in polymer materials using light ions but also in other materials such as glass, ceramics, etc. by use of heavy ions. The focusing system allows focusing of charged particles with a maximum rigidity of 11 MeV amu/q 2. The usual resolution in high and low current modes is 2 × 3 µm 2 for a 100 pA and 0.3 × 0.5 µm 2 for the 2000 ions/s of 2 MeV protons, respectively. A detailed facility description is given in the paper. The applications of focused beams of heavy ions as well as examples of light ions utilizing are also presented in the article.
Nuclear microprobe performance in high-current proton beam mode for micro-PIXE
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2017
The performance of a nuclear microprobe is dominantly determined by the brightness of the injected ion beam. At Jožef Stefan Institute (JSI), negative hydrogen ion beams are created in a multicusp ion source and injected into a 2 MV tandetron accelerator. The output characteristics of the multicusp ion source were tuned in order to obtain matching proton beam intensities for the ion accelerator and for the object slits as well. For the optimal focusing of the proton beam in a high-current mode (I > 100 pA) to the submicrometer dimensions, dedicated thin nanostructures with sharp edges have been manufactured. Set of nanostructures was micromachined by focused ion beam (FIB) at film reference material, produced by Institute for Reference Materials and Measurements (IRMM) and constituted of 57 lg/cm 2 of titanium on vitreous carbon substrate. The proton beam profiles were measured by beam scans across the nanostructures over long measuring times, indicating eventual slow drifts of the sample from a reference beam direction. Overall, proton beam dimensions of 600 nm were obtained, demonstrating appropriate stability for micro-PIXE (micro-Particle Induced X-ray Emission) at sub-micrometer resolution for elemental analysis of biological tissue samples prepared in a freeze-dried state or in a frozen-hydrated state. The resulting performance required for micro-PIXE analysis in a high current mode with a 3 MeV proton beam is presented.
A high brightness proton injector for the Tandetron accelerator at Jožef Stefan Institute
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2014
Jožef Stefan Institute recently commissioned a high brightness H À ion beam injection system for its existing tandem accelerator facility. Custom developed by High Voltage Engineering Europa, the multicusp ion source has been tuned to deliver at the entrance of the Tandetron™ accelerator H À ion beams with a measured brightness of 17.1 A m À2 rad À2 eV À1 at 170 lA, equivalent to an energy normalized beam emittance of 0.767 p mm mrad MeV 1/2 . Upgrading the accelerator facility with the new injection system provides two main advantages. First, the high brightness of the new ion source enables the reduction of object slit aperture and the reduction of acceptance angle at the nuclear microprobe, resulting in a reduced beam size at selected beam intensity, which significantly improves the probe resolution for micro-PIXE applications. Secondly, the upgrade strongly enhances the accelerator up-time since H and He beams are produced by independent ion sources, introducing a constant availability of 3 He beam for fusion-related research with NRA.
High-intensity positive beams extracted from a compact double-chamber ion source
Review of Scientific Instruments, 2005
This work presents the design and development of a simple ion source, the associated ion extraction optics, and the beam transport of a low-energy and high-current proton accelerator. In its actual version, the ion source can deliver positive proton currents up to 100 mA. This rather high beam current is achieved by adding a small ionization chamber between the discharge chamber containing the filament and the extraction electrode of the ion source. Different parameters of the ion source and the injection beam line are evaluated by means of computer simulations to optimize the beam production and transmission.
Production of intense radioactive ion beams using two accelerators
Physical Review C, 1990
An intense beam (1. 5x10' particles/sec) of radioactive "N'+ ions (half-life: Tv2 10 min) has been produced and accelerated to 0.65 MeV/nucleon, by coupling two cyclotrons with an electron cyclotron resonance ion source. This is the first time a short-lived radioactive ion beam has been produced by this method, at such an energy and with such a high intensity, a result which opens up a wide field in many applications. The first experiment along these lines will be the measurement of the cross section for the nuclear reaction 'H("N, y)'~O which is the crucial reaction for the operation of the so-called hot CNO cycle in nuclear astrophysics.
Development of the RF ion source for use in accelerator-based microprobes
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2007
A helicon and a multicusp version of radio-frequency ion sources with compact permanent magnet systems have developed and tested to show the following performance data: plasma density of 10 11-9•10 12 cm À3 , pressure of 2-10 mTorr, beam current densities of 10-130 mA/cm 2 , brightness $100 A/(m 2 rad 2 eV), energy spread 8-30 eV and an RF power input into the plasma of 40-400 W. Possibilities for a further increase in the differential brightness of the RF ion sources are discussed.
Possibility to increase RF ion source brightness for nuclear microprobe applications
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2003
The paper discusses possible ways of improving brightness of RF ion sources intended for use as nuclear microprobe injectors, by increasing the plasma density. The plasma density increase is achieved by setting up an efficient inductively coupled plasma radio frequency (RF) discharge with an external magnetic field. It is shown that in RF ion sources it is possible to create suitable conditions for excitation of the helicon mode as well as the ion-sound parametric instability leading to electron heating, helicon damping and maintenance of the RF discharge while the RF power input into the plasma need not exceed 500 W.
Ion Sources at the Michigan Ion Beam Laboratory: Capabilities and Performance
2009
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.
Development of an ion micro-beam facility at Institute of Physics, Bhubaneswar
Sia tc Un i ve rsit y o f New York at A lbany. Alhan y 12222. USA Recei ved 7 ovcmhe r 2000 A n inn mi cro-hc;nn facili ty as hccn setup at one of the hcam lines of th e 3MV tandem Pell et ron accelerator facilit y at lOP. Bhu hancswar. Thi s is th e first faci lit y of its kind in th e country ha ving potenti al appli cati ons in the growing li clds invol ving semico nd uctors. materials science. bio logy. archeolog y and environmenta l science. from hoth ~cien tili c and incl w.trial point of view. So f;n• we have achieved a sp ati al reso luti on of 4 Jlm. A bri ef descripti on o f the cxperimc11 tal set-u p is given. Elemcnt < il maps. oh t;Jincd hy RBS measurements on a tran smi ss ion electro n mi cro scope grid and on ep itax ial _!.!o ldsilicide islands grown on Si(II 0) sur faces. arc presented.