iThemba LABS
Vision
To be the leading African organisation for research, training and expertise in accelerator based sciences and technologies.
Mission
To provide state of the art facilities and programmes for high quality research, training and services in nuclear sciences and applications for the benefit of the people of South Africa and the continent in general.
iThemba LABS operates the only cyclotron facilities in the African continent and the separated sector cyclotron is the largest accelerator facility in the Southern Hemisphere. The k-200 separated sector cyclotron can accelerate protons to energies of 200MeV, and heavier particles to much higher energies. Smaller accelerators at the Western Cape site are two injector cyclotrons, one providing intense beams of light ions, and the other, beams of polarized light ions or heavy ions; a 3MV Tandetron used mainly for research utilising ion beam analysis techniques; and a k=11 cyclotron for the production of the radioisotope Flourine-18 for supplying to local nuclear medicine facilities for imaging purposes. Accelerators at the Gauteng site include a 6MV tandem accelerator with a specialised high energy analysis system for Atomic Mass Spectrometry (AMS), and two low energy electrostatic accelerators for ion implantation and other surface science studies.
The accelerators are used to accelerate charged particles for basic nuclear physics research, radioisotope production, radiobiology research related to particle therapy, and applications such as radiation hardness testing of electronic components used in satellites and detector calibrations.
iThemba LABS have various collaboration agreements and joint training programmes with Higher Education Institutions and research laboratories around the world as a means to contribute to the human capital development mandate of the NRF. The laboratory also provides a platform for SA based researchers and postgraduate students to access global research facilities such as CERN, JINR and GSI/FAIR.
To maintain and increase the excellence of the research and training activities, as well as respond to the demands from the research and isotope supply, iThemba LABS has developed a globally competitive research strategy and a related research infrastructure acquisition plan, based on the South African Isotope Facility (SAIF) project, which has two components: The ACE-Isotopes and the ACE-Beams. The first phase consists of the acquisition of the C70 cyclotron and the Low Energy Radioactive Beam (LERIB) project which will make iThemba LABS internationally competitive by expanding the nuclear astrophysics research and the study of neutron-rich nuclei, and materials research using rare isotopes.
Subatomic Physics
The research in basic nuclear physics involves mainly experimental studies of the properties of the nuclei at moderate to high excitation energy and angular momentum, as well as studies of the different mechanisms through which nuclear reactions occur.
Particle beams accelerated through the Separated Sector Cyclotron are used in the experiments. Light charged particles emitted in nuclear reactions are studied with the K-600 magnetic spectrometer.
Gamma-ray spectroscopy is carried out with the AFRODITE gamma-ray array. Neutron facility provides a beam of collimated near mono-energetic neutrons with energies up to 200 MeV. A multi-purpose large 1.5 m scattering chamber is used for studying charge particles emission in the nuclear reactions. Precise cross sections for nuclear reactions are measured on a dedicated beam line – sigma-R line.
The research in applied nuclear physics is focused on studying the natural and anthropogenic radioactivity of our environment and its use in practical applications.
All the studies are directed towards finding how these tiny pieces of matter – the atomic nuclei – are built, how they interact with each other, and how the acquired knowledge can be applied in order to improve our everyday life.
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Tandem Accelerator Mass Spectrometry (TAMS)
TAMS is a leading primary centre of research, training and service expertise in accelerator based sciences and technologies to advance science in South Africa and beyond.
It provides advanced, viable, multidisciplinary facilities for research, training and services in the fields of nuclear related sciences for the pride and benefit of all the people of South Africa and rest of the continent.
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Materials Research
The Materials Research Department (MRD) activities focus on research, modification and characterisation of materials using low energy ion beams, and other instrumental techniques for surface characterisation. The MRD has an extensive network of collaborators at national, African and international level.
The MRD has developed strong areas of expertise in ion-beam microprobe applications, specialised in biological applications in which they have become world leaders. This is closely coupled with the simultaneous development of specialised specimen preparation using cryo-techniques. The cryo-preparation laboratory has developed into a unique national facility. While the micro-probe facility is widely known and has a broad base of users and applications, the relatively younger cryo-preparation facility is not yet widely known.
Materials studies have been extended by facilities for XRD measurements. These techniques are complementary to ion-beam techniques and are appropriate for a research group that has as a strategic aim materials characterisation rather than purely ion beam applications. These techniques have their own specialised instruments and requirements. The machines are fully utilized.
The research of the group can be divided into the following broad themes:
. Ion-solid interaction: Study of fundamentals parameters
. Ion Beam Analysis (IBA)
· Nano-sciences and Nano-technology
. Materials engineering
. Thin film physics using material characterization and modification with ion beams
· Biological systems with a focus on elemental distribution and transport
· Geological and environmental studies using ion beams
· Innovation in instrumentation and electronics
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Nuclear Medicine
Since the late 1980’s, the Nuclear medicine related endeavours at iThemba LABS has been a major pillar of the facility that has been supported by the two main activities: i) the Radioisotope Production Programme and ii) Particle Therapy Programme with protons and neutrons. As the iThemba LABS proton and neutron therapy programme diminished over recent years, the activities was replaced as per the Long Range Plan (LRP) resolution by radiation biology and radiation physics research activities. In order to optimize synergy and efficiency at iThemba LABS for the Nuclear Medicine related activities, both activities have been consolidated into one single Nuclear Medicine Department in 2018 which comprise of the Division: Radiopharmaceutical and Radiochemicals Manufacturing and the Division: Radiation Biophysics.
Subatomic Physics – Infrastructure
K600 Magnetic Spectrometer
The K=600 magnetic spectrometer at iThemba LABS is a high resolution kinematically corrected magnetic spectrometer for light ions. It has the capability to measure inelastically scattered particles and reactions at extreme forward angles that includes zero degrees, making it one of only two facilities worldwide (the other being at RCNP, Japan) where high energy resolution is combined with zero degree measurements at medium beam energies.
ALBA (African LaBr Array)
Array of large-volume LaBr3:Ce detectors of 89mm diameter and 203mm length. Currently 6 detectors available and will be increased to 23 detectors in 2020.
Fast Timing Array
Eight 2”x”2 LaBr3(Ce) detectors, which are scintillation detectors bearing good efficiency for photon detection (~3%) and excellent timing resolution (~<400ps).
AFRODITE (Clover+BGO array)
14 Clover and BGO detectors are currently available. This will increase to 18 Clover and 17 BGO in 2020. Each Clover consists of four 50 x 70 mm HPGe crystals.
LEPS (Low-energy photon detectors)
Eight Low Energy Photon detector are available and can be coupled to ALBA or AFRODITE detectors. The LEPS consist of four segmented planar Ge detectors of 2800 mm2 x 10 mm.
CAKE (array of silicon detectors)
CAKE consists of up to six wedge-shaped double sided silicon strip detectors (DSSSDs) of the MMM design, placed in a lampshade configuration upstream from the target ladder.
Electron Spectrometer
The electron spectrometer consists of two Siegbahn-Kleinheiz lenses which can be operated together or independently. Electrons are focussed by the lens from the target onto a Si(Li) detectors of up to 6mm thickness.
Quasi mono-energetic neutron beams
Quasi-monoenergetic neutrons are typically produced in the D-line (neutron) facility by the 7Li(p,n)7Be or 9Be(p,n)9B reactions. Even at 200 MeV virtually single-turn extracted, nanosecond-pulsed beam can be delivered making a background free interval between pulses possible.
Tape Station
A tape station is available for decay measurements on the A-Line, when the 1.5m scattering chamber is removed. The single-spool design has 50m of 12 mm wide mylar tape, capable of moving at a maximum speed of 1 ms-1, and transporting activity 2.5 m from the implantation point to a measuring station.
Environmental Radiation Laboratory
The laboratory-based hyper-pure germanium (HPGe) detector is a p-type, 45% relative efficiency, 2 keV FWHM resolution at 1.33 MeV Canberra detector system. The HPGe detector is customized for measuring low-activity samples. The system is placed in a low-background environment by surrounding the detector crystal with 10 cm thick lead castle. The castle has thin copper lining inside to attenuate the low-energy X-rays introduced by gamma-rays mainly in lead.
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TAMS – Infrastructure
EN Tandem Accelerator, with
64-sample AMS ion source.
860 single-sample sputter source.
ALPHATROSS ion source.
AMS Low Energy Injection and High Energy Analysis Systems.
AMS Carbon-14 sample preparation laboratory.
AMS cosmogenic isotope sample preparation facilities.
Oxford Scanning Microprobe for Particle-Induced X-ray Emission (PIXE) and Rutherford Back-Scattering (RBS).
Heavy Ion Elastic Recoil Detection (HI ERDA) set-up.
Large scattering chamber for Total Ion Beam Analysis (TIBA).
Low-energy nuclear-reaction set-up.
Thermofisher Delta V Mass Spectrometer.
Los Gatos Laser Water Isotope Analyser (LWIA).
Two Perkin Elmer Liquid Scintillation Counters for tritium and Carbon-14 hydrology.
Varian 350D/300XP ion implanter.
Varian 200-20AF ion implanter.
Broad Energy-Range High-Purity Germanium (BEGE) detector in lead castle.
Mechanical Workshop.
Electronics Workshop.
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Materials Research – Infrastructure
3 MV Tandetron Particle Acclelerator
The 3 MV tandetron particle accelerator was installed and commissioned in 2017 and has two multicusp sources for H– and He– -ions with current thresholds of ~ 1mA before the low energy magnet, and ~ 200 µA post-acceleration. A Heavy Ion (HI) Sputtering Source is also included in the accelerator infrastructure. The availability of a HI Sputter Source has created many possibilities for research on Ion-Solid Interaction research. In the basic ion-solid interaction research domain, measurements of fundament parameters (Stopping force S(E), straggling, effective ranges for analysis), which are involved in the physics of slowing down processes of HI in heavy metals will be carried out. Furthermore, this provides appropriate infrastructure to users to perform surface characterization elemental depth profiling with highly charged heavy ions particularly in the fields of nano-sciences, materials engineering, condensed matter and characterization of samples used in nuclear physics experiments at the Separated Sector Cyclotron (SSC).
Particles acceleration:
Accelerator terminal voltage tunable from 80 kV to 3 MV (source injection voltage is up to 30 kV).
H+, He+ and He++ beams in standard configuration with maximum energies of 3.4, 3.4 and 5.1 MeV, respectively.
Beam spot size from 1 mm to 6 mm for solid state beamline and up to ~1µm for the Nuclear Microprobe (NMP) beamline.
Maximum beam current of ~100 µA on target depending on ion species and energies.
3He, 15N and 16O beams are also available for nuclear reaction analysis (NRA) or elastic recoil detection analysis (ERDA).
Ion Beam Analysis Techniques
Rutherford Backscattering Spectrometry (RBS)
RBS is based on Rutherford’s experiment which lead to the discovery of the nucleus of the atom. Today RBS, is a powerful tool for determining elemental information, for example in the characterization of thin films. Helium ions (alpha particles) are accelerated to energies between 1 and 4 MeV. These alpha particles are then focused on the sample to be analysed. Measurements are done in a vacuum chamber where an area of a few square millimetres is analysed. A silicon detector tilted at 165° detects the backscattered alphas from the sample. RBS analysis is used mostly for determining the composition and the depth distribution of elements but by aligning the crystallographic axes of the sample to the incoming alpha particles, RBS channelling analysis provides information about the crystal structure of the sample. RBS is a non-destructive and multi-elemental analysis technique.
Elastic Recoil Detection Analysis (ERDA)
The quantitative and sensitive analysis of light elements in thin films is in general a non-trivial task in materials science, since there are only a few techniques available to get reliable and accurate profiles. Elastic recoil detection (ERD) using energetic heavy ions is such a technique. Recoiled ions scattered off a thin film by an energetic heavy ion beam impinging the surface at a glancing angle are detected under forward direction and analysed for their nuclear charge or mass and energy. A sensitivity in the ppm region with a depth resolution of some 10 nm and a depth range of 1 micron is obtained in standard ERD set-ups.
Nuclear microprobe (microPIXE)
Since its installation the nuclear microprobe (NMP) has been successfully used in the analysis of samples from fields including archaeology, biology, geology, materials science and medicine. The microprobe target chamber is a modified version that replaced the conventional Oxford Microbeams chamber delivered in 1991. A custom-made lid has been installed that allows for stepper motor control of the target ladder in the X-, Y- and Z-directions. Charged particles (protons, alpha particles or heavy ions) are used to create inner-shell vacancies in the atoms of the specimen. Protons of 1-4 MeV energy are most often used. Their slowing down in matter is smooth and well characterized, with little scattering and deflection. The process is therefore easy to quantify. PIXE spectra are usually collected in energy-dispersive mode and all elements with atomic numbers above 10 (Na and above) can in principle be detected at once. The characteristic X-rays of lighter elements are absorbed in the windows of routinely used Si(Li) or HPGe detectors. Typically reported sensitivities are 10-20 ppm for Na to Cl and 1-10 ppm for Ca and heavier elements. No information related to chemical identity, coordination chemistry or oxidation state of a particular element could be directly obtained. The GeoPIXE software package is used for off-line PIXE data analysis and quantitative imaging. For point PIXE analysis GUPIX software can also be used.
Physical Properties Measurement System (PPMS)
This system allows for the measurement of electrical (electrical conductivity, Hall effect, etc), thermal (thermal conductivity thermo-power, specific heat, etc.), and magnetic (DC magnetization and AC susceptibility) properties at magnetic fields up to an optional 7, 9 or 16T (superconducting solenoid magnets), and accurately controlled temperatures in the range 1.9 < T < 400K. Temperatures up to 1000K can be obtained with an optional “oven” insert. The apparatus is PC controlled and is completely programmable (such that a prolonged sequence of measurements under varying temperature and field values or sweeps can be done). The PPMS is readily expandable, with a variety of specialist specimen stages and measurement options and very user friendly. It is supplied either in a conventional cryostat dewar, which is very economical in the use of liquid helium, or in a cryostat with built-in cryo-refrigerator (EverCool option).
Atomic Force Microscope (AFM)
A high resolution AFM imaging system which consists a DI Nanoscope V SPM control station, a Dimension V Scan head with a hybrid XYZ closed loop scanner, a motorized stage with a sample chuck size of 150 mm in diameter, and an optical microscope which provides real-time color video display at a 1.5 µm resolution with a maximum field of view of 675 µm. Includes an integrated vacuum system which can be activated to lock large samples on the sample stage. Samples can be scanned to a maximum scan-field of 105 µm2. The Nano-Man V AFM equipped with a VT-103-3K-2 acoustic enclosure, is a lithography dedicated system capable of both nano-lithography and nano-manipulation in a humidity controlled ambient in virtually all three basic AFM imaging techniques, viz Tapping Mode, Contact Mode, and Non-Contact Mode. Additional supported imaging techniques include Magnetic Force Microscopy (MFM), Electric Force Microscopy (EFM) and Force Imaging through Force distance curves. The Nanoman AFM also has capabilities to function as an STM. With such a wide variety of imaging techniques this make the Nanoman V AFM a most valuable a surface analytical tool for nano-characterization of a wide range of materials. Surface features such as grain sizes, step-heights and the overall surface roughness can be quantified at near atomic resolution. The special lithographic capability of Nanoman V AFM makes it an even more valuable tool in the low-dimensional semiconductor device fabrication technology.
X-ray Diffraction (XRD)
The XRD facility offers a first class service in terms of technical and/or scientific assistance samples, a high throughput of samples with excellent data quality. The XRD lab welcomes all academic institutions on a regional, national and continental level. The facility comprises of a BRUKER X-ray diffractometer for microstructural characterization of specimens using a non-destructive technique. Information obtained from the diffractogram benefits a wide range of Departments such as Chemistry, Polymers, Physics, Geology, Engineering, Electronics, Pharmaceutics, thus covering a broad field of research comprising nanomaterials, fuel cells, catalysts, bio-coatings, residual stress in surface coatings, stress determination in laser bent steel plates for automotive industry, soils study in wine farms production.
Multi-Functional Integrated Optical Characterization Platform
For thin film Optical Analysis, we are able to do the following:
Absorption, transmission, and reflectivity in the wavelength range from 200 to 2600 nm
Measurement of diffuse reflection, including specular reflection using an Integrating Sphere from 200 to 2600 nm.
Reflectometry technique for transparent film thickness measurement by measuring reflectance for different wavelengths
Ellipsometry to determine the optical constants, refractive index, surface roughness and film thickness.
Fluorescence.
Raman operating at 532 nm which is good for powdered samples with low fluorescence and materials where C-OH structural information is important.
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Radionuclides – Infrastructure
1 Horizontal Beam Target station
2 Vertical Beam Target Station
3 Alpha Emitter Target Station
4 Experimental Station
5 11 MeV cyclotron
6 Hot Cells (14)
7 Cleanrooms (x3)
8 MicroLab
9 Production and Quality Control LABS
10 Laminar Flow Cabinets
11 Biohazard Cabinets
12 Fume Hoods
13 HPGe Detectors (x2)
14 High Performance Liquid Chromatography (HPLC)
15 Gas Chromatography (GC)
16 Induced Coupled Plasma Spectrometer (ICP)
17 UV/Vis spectrometer
18 Ionisation Chamber Capintec
19 Atomic Absorption Spectrometer
20 FT-IT Spectrometer
21 Hot Air Oven
22 Vacuum Oven
23 Autoclave
24 Sonic Water Bath
25 Weighing Balance
26 Hot Plate with magnetic stirrer
27 Autotitrator
28 pH meter
29 Water Purification System
30 Furnace
31 Freeze Dryer
32 Microplate Reader
33 Melting point apparatus
34 TLC Controller and Scanner
35 Particle Counter
36 Vortex Mixer
37 Stuart Flask Shaker
38 Vinten Isocal
39 Cooling Systems
40 Control Systems
41 Transporter System
42 Comecer Hot Cells
42 TracerLab FDG systems
43 Timotheo Dispensing System
Notice: Please contact international@erc-assoc.org if you represent this Research Institution and have identified any required additions or modifications to the above information.