Speaker
Description
The Centre for Accelerator Science (CAS) of the Australian Nuclear Science and Technology Organisation (ANSTO) is a national state-of-art facility for applied accelerator science, equipped with 10 MV Van de Graaff ANTARES [1] accelerator to accelerate mono-energetic ions, such as proton up to 10 MeV (ideally 20 MeV), light and heavy ions up to 120 MeV.
The Heavy Ion Nuclear Microprobes (HIMP) beamline installed on the ANTARES accelerator system is a unique facility in Australia capable of focussing ion beams down to a 1µm spot size, or to operate with a defocused beam of mm size. In 2020, the HIMP end station was upgraded with the installation of the External Ion micro-Beam Facility (EBIF), consisting in an enclosed chamber filled with air at atmospheric pressure and room temperature dedicated to irradiation of living samples [2]. The microbeam is extracted from vacuum through a 1µm thick Si3N4 window without compromising the quality of the beam.
Three irradiation modalities are available: i) continuous raster scanning of the microbeam across µm2 and mm2 areas, ii) scanning of the sample via motorised XY stage across cm2 areas, and iii) hybrid scanning (simultaneous raster scan of the microbeam and translation of the sample) across areas of max 50 x 50 mm2. The hybrid scanning allows for more complex scan patterns to be performed: a customisable pattern characterised by peaks and valleys, as typically encountered in mini-beam application, is achievable with micro-resolution.
Sample positioning and alignment is achieved via motorised manipulator with micro-resolution on XY, cameras with telecentric lenses (pixel res. 0.86µm/pixel) and laser sensor with 2µm repeatability for Z positioning. The beam spot dimension, the beam trace, and the dose uniformity are measured using EBT3 GAFChromic films. Irradiation of 2D/3D cell cultures can be performed with a wide range of ion species, LET, and dose rates from mGy/s to kGy/s.
The accelerator hall is located in proximity of the radiobiology facilities for pre- and post-irradiation sample handling, including PC1 and PC2 laboratories and radioactive contamination controlled PC1 and 2 certified laboratories, and animal house. The available capabilities are gamma-ray irradiator (GATRI), XRad320 (Precision X-ray) and fluorescence microscopy system. The available bio cellular techniques are immunocytochemistry (ICC), Immunohistology (IHC), flow cytometry, digital PCR, proliferation, survival, ROS and damage detection/repair assays.
The capability is well suited for applications such as adherent human or plant cell exposure to harsh radiation environments, or for fundamental radiobiology pertinent to design of particle therapy. ANSTO is actively involved in research concerning radiobiology for space: adherent fibroblast cells have been irradiated with proton microbeams at different doses and dose rates to investigate the DNA breaks and repair mechanism during manned mission to space [3]. The constant development and improvement of the capabilities makes the facility suitable for fundamental research applied to the field of particle therapy.
References
[1] R. Siegele et al., "The ANSTO high energy heavy ion microprobe," Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, vol. 158, no. 1-4, pp. 31-38, 1999, doi: 10.1016/s0168-583x(99)00393-6.
[2] S. Peracchi et al., "Australia’s External Ion Microbeam Irradiation Facility For Space Radiation Effects Testing," in 22nd European Conference on Radiation and Its Effects on Components and Systems (RADECS), Venice, Italy, pp. 140-146, 2022, doi: 10.1109/RADECS55911.2022.10412528.
[3] M. L. Ferlazzo and N. Foray, "Space radiobiology needs realistic hypotheses and relevant methodology," (in eng), Proc Natl Acad Sci U S A, vol. 114, no. 33, p. E6733, 2017/08// 2017, doi: 10.1073/pnas.1710545114.
Contact:
Accelerator Scientist: Stefania Peracchi, speracch@ansto.gov.au
ANSTO Radiobiologist: Melanie Ferlazzo, ferlazzm@ansto.gov.au
