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The Infrared Microspectroscopy Beamline at the Australian Synchrotron is equipped with a Fourier transform infrared (FTIR) spectrometer, which is coupled with an infrared (IR) microscope and a choice of two detectors: a single-point narrow-band mercury cadmium telluride (MCT) detector and a 64 × 64 multi-pixel focal plane array (FPA) imaging detector. A scanning-based point-by-point mapping method is commonly used with a tightly focused synchrotron IR beam at the sample plane, using an MCT detector and a matching 36× IR reflecting objective and condenser (NA = 0.5), which is time consuming. In this study, the beam size at the sample plane was increased using a 15× objective and the spatio-spectral aberrations were investigated. A correlation-based semi-synthetic computational optical approach was applied to assess the possibilities of exploiting the aberrations to perform rapid imaging rather than a mapping approach.

The first X-ray Extended Range Technique (XERT)-like experiment at the Australian Synchrotron, Australia, is presented. In this experiment X-ray mass attenuation coefficients are measured across an energy range including the zinc K-absorption edge and X-ray absorption fine structure (XAFS). These high-accuracy measurements are recorded at 496 energies from 8.51 keV to 11.59 keV. The XERT protocol dictates that systematic errors due to dark current nonlinearities, correction for blank measurements, full-foil mapping to characterize the absolute value of attenuation, scattering, harmonics and roughness are measured over an extended range of experimental parameter space. This results in data for better analysis, culminating in measurement of mass attenuation coefficients across the zinc K-edge to 0.023–0.036% accuracy. Dark current corrections are energy- and structure-dependent and the magnitude of correction reached 57% for thicker samples but was still large and significant for thin samples. Blank measurements scaled thin foil attenuation coefficients by 60–500%; and up to 90% even for thicker foils. Full-foil mapping and characterization corrected discrepancies between foils of up to 20%, rendering the possibility of absolute measurements of attenuation. Fluorescence scattering was also a major correction. Harmonics, roughness and bandwidth were explored. The energy was calibrated using standard reference foils. These results represent the most extensive and accurate measurements of zinc which enable investigations of discrepancies between current theory and experiments. This work was almost fully automated from this first experiment at the Australian Synchrotron, greatly increasing the possibility for large-scale studies using XERT.

Spatially fractionated ultra-high-dose-rate beams used during microbeam radiation therapy (MRT) have been shown to increase the differential response between normal and tumour tissue. Quality assurance of MRT requires a dosimeter that possesses tissue equivalence, high radiation tolerance and spatial resolution. This is currently an unsolved challenge. This work explored the use of a 500 nm thick organic semiconductor for MRT dosimetry on the Imaging and Medical Beamline at the Australian Synchrotron. Three beam filters were used to irradiate the device with peak energies of 48, 76 and 88 keV with respective dose rates of 3668, 500 and 209 Gy s−1. The response of the device stabilized to 30% efficiency after an irradiation dose of 30 kGy, with a 0.5% variation at doses of 35 kGy and higher. The calibration factor after pre-irradiation was determined to be 1.02 ± 0.005 µGy per count across all three X-ray energy spectra, demonstrating the unique advantage of using tissue-equivalent materials for dosimetry. The percentage depth dose curve was within ±5% of the PTW microDiamond detector. The broad beam was fractionated into 50 microbeams (50 µm FHWM and 400 µm centre-to-centre distance). For each beam filter, the FWHMs of all 50 microbeams were measured to be 51 ± 1.4, 53 ± 1.4 and 69 ± 1.9 µm, for the highest to lowest dose rate, respectively. The variation in response suggested the photodetector possessed dose-rate dependence. However, its ability to reconstruct the microbeam profile was affected by the presence of additional dose peaks adjacent to the one generated by the X-ray microbeam. Geant4 simulations proved that the additional peaks were due to optical photons generated in the barrier film coupled to the sensitive volume. The simulations also confirmed that the amplitude of the additional peak in comparison with the microbeam decreased for spectra with lower peak energies, as observed in the experimental data. The material packaging can be optimized during fabrication by solution processing onto a flexible substrate with a non-fluorescent barrier film. With these improvements, organic photodetectors show promising prospects as a cost-effective high spatial resolution tissue-equivalent flexible dosimeter for synchrotron radiation fields.

Metal homeostasis is integral to normal plant growth and development. During plant–pathogen interactions, the host and pathogen compete for the same nutrients, potentially impacting nutritional homeostasis. Our knowledge of outcome of the interaction in terms of metal homeostasis is still limited. Here, we employed the X-ray fluorescence microscopy (XFM) beamline at the Australian Synchrotron to visualize and analyse the fate of nutrients in wheat leaves infected with Pyrenophora tritici-repentis, a necrotrophic fungal pathogen. We sought to (i) evaluate the utility of XFM for sub-micron mapping of essential mineral nutrients and (ii) examine the spatiotemporal impact of a pathogen on nutrient distribution in leaves. XFM maps of K, Ca, Fe, Cu, Mn, and Zn revealed substantial hyperaccumulation within, and depletion around, the infected region relative to uninfected control samples. Fungal mycelia were visualized as thread-like structures in the Cu and Zn maps. The hyperaccumulation of Mn in the lesion and localized depletion in asymptomatic tissue surrounding the lesion was unexpected. Similarly, Ca accumulated at the periphery of the symptomatic region and as microaccumulations aligning with fungal mycelia. Collectively, our results highlight that XFM imaging provides the capability for high-resolution mapping of elements to probe nutrient distribution in hydrated diseased leaves in situ., Synchrotron X-ray fluorescence microscopy elemental maps highlight major nutrient re-distribution during disease progression.

Polarisation analysis in the mid-infrared fingerprint region was carried out on thin (∼1 μm) Si and SiO2 films evaporated via glancing angle deposition (GLAD) method at 70∘ to the normal. Synchrotron-based infrared microspectroscopic measurements were carried out on the Infrared Microspectroscopy (IRM) beamline at Australian Synchrotron. Specific absorption bands, particularly Si-O-Si stretching vibration, was found to follow the angular dependence of ∼cos2θ, consistent with the absorption anisotropy. This unexpected anisotropy stems from the enhanced absorption in nano-crevices, which have orientation following the cos2θ angular dependence as revealed by Fourier transforming the image of the surface of 3D columnar films and numerical modeling of light field enhancement by sub-wavelength nano-crevices.

Exceptionally large crystals of posnjakite, Cu4SO4(OH)6(H2O), formed during corrosion of a Swagelock(tm) Snubber copper gasket within the MX1 beamline at the ANSTO-Melbourne, Australian Synchrotron. The crystal structure was solved using synchrotron radiation and revealed a structure based upon [Cu4(OH)6(H2O)O] sheets, which contain Jahn–Teller-distorted Cu octa­hedra., Exceptionally large crystals of posnjakite, Cu4SO4(OH)6(H2O), formed during corrosion of a Swagelock(tm) Snubber copper gasket within the MX1 beamline at the ANSTO-Melbourne, Australian Synchrotron. The crystal structure was solved using synchrotron radiation to R 1 = 0.029 and revealed a structure based upon [Cu4(OH)6(H2O)O] sheets, which contain Jahn–Teller-distorted Cu octa­hedra. The sulfate tetra­hedra are bonded to one side of the sheet via corner sharing and linked to successive sheets via extensive hydrogen bonds. The sulfate tetra­hedra are split and rotated, which enables additional hydrogen bonds.

In the Australian Synchrotron's short history, we have made some important advances in instruments and capabilities that can be employed to study art and archaeology. In this article, we describe the capabilities at the Australian Synchrotron that are well-suited to investigating art, archaeology, and cultural heritage. We also present some case studies that demonstrate the breadth and impact of science that has been performed by researchers using these capabilities. Synchrotron radiation has many advantages that make it ideally suited to investigating art, archaeology, and cultural heritage. The broad spectrum of radiation that can be employed and, in particular, the penetrating nature of the radiation at hard X-ray energies give the ability to conduct 3D reconstruction with tomography. In many cases, the techniques can be non-destructive and performed in situ. The intense infrared radiation allows infrared microscopy at diffraction-limited resolution and the recently developed attenuated total internal reflection mode can probe the surface of very delicate samples. In the following, we describe the relevant beamlines, their capabilities, and then illustrate with some key examples of research, from paleobotany to the investigation of paintings.

An in-situ study on the formation mechanism of plsatic layer was carried out by using a 4 kg laboratory-scale coke oven under controlled heating conditions. The coke oven rig enabled in-situ measurements of internal gas pressure (IGP) and temperature profiles in five locations in the coal charge and allowed sampling of semi-coke which consisted of the coke/semi-cokes, the plastic layers and loose coal. Six Australian coking coals with varying properties were used in the coking experiments. The semi-coke samples were scanned by micro-CT at the Imaging and Medical Beamline at Australian Synchrotron to study the physical structure transitions inside the thermoplastic regions and investigate the fissure patterns at the coke/semi-coke sides. The thicknesses of the plastic layers in different locations inside the coal charge were estimated from the measured temperature profiles and the initial softening temperatures and the solidification temperatures measured from the Gieseler fluidity tests. The results showed that the thicknesses of the plastic layers increased from the heating wall to the center of the coal charge. The IGP curves measured in different locations were used to obtain the maximum IGP values and the IGP termination temperatures across the coal charge. The difference in the extents of fissuring appeared to influence the maximum IGPs measured at the center of the oven. The higher extent of fissurin appeared to facilitate the release of volatile matterfrom the thermoplsatic region through the semi-coke sides, thus leading to lower maximum IGPs at the center. It was found that the extents of the fissuring and the maximum IGPs at the center were sensitive to the coal properties such as the petrographic properties, Gieseler maximum fluidity and volatile matter content.

The Imaging and Medical Beamline (IMBL) is a superconducting multipole wiggler-based beamline at the 3 GeV Australian Synchrotron operated by the Australian Nuclear Science and Technology Organisation (ANSTO). The beamline delivers hard X-rays in the 25–120 keV energy range and offers the potential for a range of biomedical X-ray applications, including radiotherapy and medical imaging experiments. One of the imaging modalities available at IMBL is propagation-based X-ray phase-contrast computed tomography (PCT). PCT produces superior results when imaging low-density materials such as soft tissue (e.g., breast mastectomies) and has the potential to be developed into a valuable medical imaging tool. We anticipate that PCT will be utilized for medical breast imaging in the near future with the advantage that it could provide better contrast than conventional X-ray absorption imaging. The unique properties of synchrotron X-ray sources such as high coherence, energy tunability, and high brightness are particularly well-suited for generating PCT data using very short exposure times on the order of less than 1 min. The coherence of synchrotron radiation allows for phase-contrast imaging with superior sensitivity to small differences in soft-tissue density. Here we also compare the results of PCT using two different detectors, as these unique source characteristics need to be complemented with a highly efficient detector. Moreover, the application of phase retrieval for PCT image reconstruction enables the use of noisier images, potentially significantly reducing the total dose received by patients during acquisition. This work is part of ongoing research into innovative tomographic methods aimed at the introduction of 3D X-ray medical imaging at the IMBL to improve the detection and diagnosis of breast cancer. Major progress in this area at the IMBL includes the characterization of a large number of mastectomy samples, both normal and cancerous, which have been scanned at clinically acceptable radiation dose levels and evaluated by expert radiologists with respect to both image quality and cancer diagnosis.

Infrared (IR) microspectroscopy is a powerful molecular fingerprinting tool widely used for the identification of structural and functional composition of biological and chemical samples. The IR microspectroscopy beamline at the Australian Synchrotron can be operated either with a single-point narrow-band mercury cadmium telluride (MCT) detector or a focal plane array (FPA) imaging detector with 64 × 64 pixels. For the implementation of indirect nonscanning imaging technology, the system was operated with the FPA detector. In this study, we propose an indirect IR imaging technique based on the principles of correlation optics using diffractive optical elements such as random pinhole array (RPA) and Fresnel zone plate (FZP). The spatial and spectral variations of point spread functions (PSFs) of the RPA and FZP were simulated for the synchrotron configuration. Intensity responses for 2D objects were simulated using the same simulation conditions and reconstructed using Lucy-Richardson algorithm. Fabrication of diffractive elements for IR wavelengths is often a challenging task as the IR transparent material substrates, such as barium fluoride and calcium fluoride, are highly susceptible to thermal shocks and brittle by nature. The diffractive elements were fabricated by ablating directly on a 100 nm thick gold coated substrate using femtosecond laser pulses. The simulation results and the fabrication outcomes demonstrate the feasibility of indirect imaging at the synchrotron IR beamline.

Synchrotron Radiotherapy (SyncRT) is a preclinical radiation treatment which delivers synchrotron x-rays to cancer targets. SyncRT allows for novel treatments such as Microbeam Radiotherapy, which has been shown to have exceptional healthy tissue sparing capabilities while maintaining good tumour control. Veterinary trials in SyncRT are anticipated to take place in the near future at the Australian Synchrotron's Imaging and Medical Beamline (IMBL). However, before veterinary trials can commence, a computerised treatment planning system (TPS) is required, which can quickly and accurately calculate the synchrotron x-ray dose through patient CT images. Furthermore, SyncRT TPS's must be familiar and intuitive to radiotherapy planners in order to alleviate necessary training and reduce user error. We have paired an accurate and fast Monte Carlo (MC) based SyncRT dose calculation algorithm with EclipseTM, the most widely implemented commercial TPS in the clinic. Using EclipseTM, we have performed preliminary SyncRT trials on dog cadavers at the IMBL, and verified calculated doses against dosimetric measurement to within 5% for heterogeneous tissue-equivalent phantoms. We have also performed a validation of the TPS against a full MC simulation for constructed heterogeneous phantoms in EclipseTM, and showed good agreement for a range of water-like tissues to within 5%–8%. Our custom EclipseTM TPS for SyncRT is ready to perform live veterinary trials at the IMBL.

The Macquarie University Deformation-DIA (MQ D-DIA) multi-anvil apparatus at the Australian Synchrotron provides a new experimental facility that enables simultaneous high-pressure and high-temperature in situ synchrotron experimentation in Australia. The MQ D-DIA can be easily deployed at any of a number of beamlines at the Australian Synchrotron, and we describe its installation at the x-ray absorption spectroscopy beamline, which enables in situ x-ray absorption near-edge spectroscopy and energy-scanning x-ray diffraction. A simple, reliable, and x-ray transparent high-pressure cell assembly has been developed for the D-DIA for which load/pressure and heater power/temperature relationships have been calibrated using in situ x-ray diffraction and “offline” mineral equilibration experiments. Additionally, we have mapped temperature distribution within the assembly using a new quantitative electron microprobe mapping technique developed for fine-grained polyphase samples. We are now investigating the speciation of geologically important trace elements in silicate melts (e.g., Zr, U, and Th) measured in situ under high pressure and temperature conditions corresponding to the Earth’s mantle. Pressure-dependent changes in speciation influence partitioning behavior, and therefore the distribution in the Earth, of many trace elements. However, previous ex situ investigations are hampered by uncertainty as to whether high-pressure speciation can be faithfully recorded in samples recovered to ambient conditions. We present preliminary results showing an increase in the coordination number of Zr dissolved as a trace component of a sodium-rich silicate melt with pressure. These results also indicate that silicate melt composition exerts a strong influence on Zr speciation.

Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy has been used widely for probing the molecular properties of materials. Coupling a synchrotron infrared (IR) beam to an ATR element using a high numerical aperture (NA) microscope objective enhances the spatial resolution, relative to transmission or transflectance microspectroscopy, by a factor proportional to the refractive index (n) of the ATR element. This work presents the development of the synchrotron macro ATR-FTIR microspectroscopy at Australian Synchrotron Infrared Microspectroscopy (IRM) Beamline, and demonstrates that high quality FTIR chemical maps of single cells and tissues can be achieved at an enhanced spatial resolution. The so-called “hybrid” macro ATR-FTIR device was developed by modifying the cantilever arm of a standard Bruker macro ATR-FTIR unit to accept germanium (Ge) ATR elements with different facet sizes (i.e. 1 mm, 250 μm and 100 μm in diameter) suitable for different types of sample surfaces. We demonstrated the capability of the technique for high-resolution single cell analysis of malaria-infected red blood cells, individual neurons in a brain tissue and cellular structures of a Eucalyptus leaf. The ability to measure a range of samples from soft membranes to hard cell wall structures demonstrates the potential of the technique for high-resolution chemical mapping across a broad range of applications in biology, medicine and environmental science.

A flow-through reaction cell has been developed for studying minerals leaching by in-situ time-resolved powder X-ray diffraction, allowing for a better understanding of the leaching mechanisms and kinetics. The cell has the capability of independent control of temperature (up to 95 &deg, C) and flow rate (&gt, 0.5 mL min&minus, 1) for atmospheric pressure leaching. It was successfully tested at the powder diffraction beamline at the Australian Synchrotron. Galena powder was leached in a citrate solution under flow-through condition at a flow rate of 0.5 mL min&minus, 1, while diffraction patterns were collected during the entire leaching process, showing rapid galena dissolution without the formation of secondary mineral phases. The flow-through cell can be used to study leaching processes of other ore minerals.

A facility for performing serial crystallography measurements has been developed at the Australian synchrotron. This facility incorporates a purpose built high viscous injector, Lipidico, as part of the macromolecular crystallography (MX2) beamline to measure large numbers of small crystals at room temperature. The goal of this technique is to enable crystals to be grown/transferred to glass syringes to be used directly in the injector for serial crystallography data collection. The advantages of this injector include the ability to respond rapidly to changes in the flow rate without interruption of the stream. Several limitations for this high viscosity injector (HVI) exist which include a restriction on the allowed sample viscosities to >10 Pa.s. Stream stability can also potentially be an issue depending on the specific properties of the sample. A detailed protocol for how to set up samples and operate the injector for serial crystallography measurements at the Australian synchrotron is presented here. The method demonstrates preparation of the sample, including the transfer of lysozyme crystals into a high viscous media (silicone grease), and the operation of the injector for data collection at MX2.

The X-ray fluorescence microscopy (XFM) beamline is an in-vacuum undulator-based X-ray fluorescence (XRF) microprobe beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the 4–27 keV energy range, permitting K emission to Cd and L and M emission for all other heavier elements. With a practical low-energy detection cut-off of approximately 1.5 keV, low-Z detection is constrained to Si, with Al detectable under favourable circumstances. The beamline has two scanning stations: a Kirkpatrick–Baez mirror microprobe, which produces a focal spot of 2 µm × 2 µm FWHM, and a large-area scanning `milliprobe', which has the beam size defined by slits. Energy-dispersive detector systems include the Maia 384, Vortex-EM and Vortex-ME3 for XRF measurement, and the EIGER2 X 1 Mpixel array detector for scanning X-ray diffraction microscopy measurements. The beamline uses event-mode data acquisition that eliminates detector system time overheads, and motion control overheads are significantly reduced through the application of an efficient raster scanning algorithm. The minimal overheads, in conjunction with short dwell times per pixel, have allowed XFM to establish techniques such as full spectroscopic XANES fluorescence imaging, XRF tomography, fly scanning ptychography and high-definition XRF imaging over large areas. XFM provides diverse analysis capabilities in the fields of medicine, biology, geology, materials science and cultural heritage. This paper discusses the beamline status, scientific showcases and future upgrades.

Absorption cross sections of cold propane, pure and broadened with H2 or He, have been recorded in the 650–1250 cm-1 region using an Enclosive Flow Cooling (EFC) cell located at the Australian Synchrotron Far-IR/THz beamline. The chosen temperatures range from 150 to 210 K to replicate similar atmospheric conditions of the giant planets. These cross sections have been normalized using data obtained from the Pacific Northwest National Laboratory, and can be used directly in comparisons with observed spectra and in radiative transfer models.

Experimental measurement of Synchrotron Radiotherapy (SyncRT) doses is challenging, especially for Microbeam Radiotherapy (MRT), which is characterised by very high dynamic ranges with spatial resolutions on the micrometer scale. Monte Carlo (MC) simulation is considered a gold standard for accurate dose calculation in radiotherapy, and is therefore routinely relied upon to produce verification data. We present a MC model for Australian Synchrotron's Imaging and Medical Beamline (IMBL), which is capable of generating accurate dosimetry data to inform and/or verify SyncRT experiments. Our MC model showed excellent agreement with dosimetric measurement for Synchrotron Broadbeam Radiotherapy (SBBR). Our MC model is also the first to achieve validation for MRT, using two methods of dosimetry, to within clinical tolerances of 5% for a 20×20 mm2 field size, except for surface measurements at 5 mm depth, which remained to within good agreement of 7.5%. Our experimental methodology has allowed us to control measurement uncertainties for MRT doses to within 5-6%, which has also not been previously achieved, and provides a confidence which until now has been lacking in MRT validation studies. The MC model is suitable for SyncRT dose calculation of clinically relevant field sizes at the IMBL, and can be extended to include medical beamlines at other Synchrotron facilities as well. The presented MC model will be used as a validation tool for treatment planning dose calculation algorithms, and is an important step towards veterinary SyncRT trials at the Australian Synchrotron.

Acetonitrile (CH3CN) and water (H2O) ice particles were generated within a collisional cooling cell coupled to the Australian Synchrotron light source. The evolution of the aerosols was tracked by infrared spectroscopy compiled over the 4000–50 cm–1 region. Gas pressure and temperature conditions were varied to replicate the lower altitudes of the Titan atmosphere allowing for comparison to far-infrared features detected by the Cassini–Huygens spacecraft. The experimental spectra show that CH3CN and H2O particles are microheterogeneous in composition and spherical in shape. CH3CN lattice bands display temperature-dependent shifts in frequency, implying that pure β-phase is present in the mixed particles. In addition, a red shift identified for the C≡N fundamental stretching mode indicates dipole–dipole and π-electron side-directed hydrogen bond coupling between segregated CH3CN and H2O phases exclusively at the grain interface. Discrete dipole approximation theory was implemented to evaluate various clust...

A microfocus macromolecular crystallography beamline at the Australian Synchrotron is presented., MX2 is an in-vacuum undulator-based crystallography beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the energy range 4.8–21 keV to a focal spot of 22 × 12 µm FWHM (H × V). At 13 keV the flux at the sample is 3.4 × 1012 photons s−1. The beamline endstation allows robotic handling of cryogenic samples via an updated SSRL SAM robot. This beamline is ideal for weakly diffracting hard-to-crystallize proteins, virus particles, protein assemblies and nucleic acids as well as smaller molecules such as inorganic catalysts and organic drug molecules. The beamline is now mature and has enjoyed a full user program for the last nine years. This paper describes the beamline status, plans for its future and some recent scientific highlights.

Radiation therapy, which uses X-rays to destroy or injure cancer cells, has become one of the most important modalities to treat the primary cancer or advanced cancer. High resolution, water equivalent and passive X-ray dosimeters are highly desirable for developing quality assurance (QA) systems for novel cancer therapy like microbeam radiation therapy (MRT) which is currently under development. Here we present the latest developments of high spatial resolution scintillator based photonic dosimeters, and their applications to clinical external radiation beam therapies: specifically high energy linear accelerator (LINAC) photon beams and low energy synchrotron photon beams. We have developed optical fiber dosimeters with spatial resolutions ranging from 50 to 500 mm and tested them with LINAC beams and synchrotron microbeams. For LINAC beams, the fiberoptic probes were exposed to a 6 MV, 10 cm by 10 cm Xray field and, the beam profiles as well as the depth dose profiles were measured at a source-to-surface distance (SSD) of 100 cm. We have also demonstrated the possibility for temporally separating Cherenkov light from the pulsed LINAC scintillation signals. Using the 50 mm fiber probes, we have successfully resolved the microstructures of the microbeams generated by the imaging and medical beamline (IMBL) at the Australian Synchrotron and measured the peak-to-valley dose ratios (PVDRs). In this paper, we summarize the results we have achieved so far, and discuss the possible solutions to the issues and challenges we have faced, also highlight the future work to further enhance the performances of the photonic dosimeters.

A new optimized size exclusion chromatography small-angle X-ray scattering (SEC-SAXS) system for biomolecular SAXS at the Australian Synchrotron SAXS/WAXS beamline has been developed. The compact configuration reduces sample dilution to maximize sensitivity. Coflow sample presentation allows an 11-fold increase in flux on sample without capillary fouling, improving throughput and data quality, which are now primarily limited by the full flux available on the beamline. Multi-wavelength fibre optic UV analysis in close proximity to the X-ray beam allows for accurate concentration determination for samples with known UV extinction coefficients and thus estimation of the molecular weight of the scattering particle from the forward X-ray scattering intensity. Fast-flow low-volume SEC columns provide sample throughput competitive with batch concentration series measurements, albeit with a concomitant reduction of potential resolution relative to lower flow rates and larger SEC columns. The performance of the system is demonstrated using a set of model proteins, and its utility to solve various challenges is illustrated with a diverse suite of protein samples. These developments increase the quality and rigor of SEC-SAXS analysis and open new avenues for biomolecular solution SEC-SAXS studies that have been challenged by low sample yields, temporal instability, radiation sensitivity and complex mixtures.

Recommendations for an experimental protocol for beam alignment/optimization and dosimetry relating to in vitro studies at the Imaging and Medical Beam Line of the Australian Synchrotron are presented. An evaluation of the protocol, based upon the consistency and reproducibility of in vitro experiments performed over several years at the Australian Synchrotron, is provided for the community.

The X-Tream dosimetry system developed at the Centre for Medical Radiation Physics (University of Wollongong, Australia) utilises a high resolution silicon Single Strip Detector to characterise synchrotron radiation microbeams for the purpose of Quality Assurance of Microbeam Radiation Therapy. Firstly, a comparison of the Silicon Strip Detector performance with respect to a conventional PinPoint Ionisation Chamber for broad beams and microbeams is given. These results are then extended to characterise the horizontal microbeam radiation field available in the high flux experimental hutch of the Imaging and Medical BeamLine at the Australian Synchrotron. The Silicon Strip Detector measured depth dose curve of the broad beam agrees very well with the PinPoint Ionisation Chamber measurements between 10 and 50 mm depth in water. Significant deviations from the PinPoint Ionisation Chamber response are observed with increasing depth. Microbeam profiles measured by the Silicon Strip Detector are well resolved but clearly affected by misalignment of the Silicon Strip Detector with respect to the microbeams. Future beamline technical improvements will alleviate this issue.

Two X-ray computed tomography (CT) datasets have been acquired for a cold-sprayed titanium sample before and after heat treatment. The datasets were collected with a beam energy of 30 keV at the Australian Synchrotron. Three-dimensional (3D) distributions of porosity in the Ti sample were reconstructed using a data-constrained modelling (DCM) technique. Quantitative analysis indicated that the heat treatment caused morphological changes to the pores and a small decrease in the overall porosity. After heat treatment, some fine porosity disappeared while the large porosity regions were essentially unaffected except for a change towards a more rounded pore shape. Interconnectivity between pores was reduced, which has implications for sealing and trapping of contaminant gases in cold-sprayed parts. The characterization technique and the workflow presented in the paper are applicable to non-destructive 3D characterization of other materials.

Introduction Rotational kilovoltage external beam radiotherapy (kV-EBRT) for breast cancer with orthovoltage tubes was recently proposed by a team at University of California at Davis, as an alternative to the typical 6-MV photon beams with breast tangential fields produced by a clinical accelerator. On this scientific basis, we propose to implement EBRT in breast cancer therapy, using a monochromatic synchrotron radiation (SR) beam and dedicated setup for irradiating the pendant breast (SR-EBRT). The same platform could be adopted to perform a computer tomography dedicated to the breast for tumor 3D localization and beam centering. Purpose To investigate, with a feasibility study in a breast phantom, the proposed technique SR-EBRT. Materials and methods The experimental plan includes dose distribution measurements with TLDs, radiochromic films and ionization chambers in cylindrical PMMA phantoms at ESRF and at the Australian Synchrotron. Results The use of the high-flux SR beam will permit dose delivery times comparable to the one of conventional radiotherapy. Preliminary data indicated that a 7:1–10:1 tumor-to-skin ratio from 60 keV to 180 keV could be achieved, and the possibility of realizing dose-painting by multiple rotations. Conclusion A SR beam down to 60 keV can be adopted for SR-EBRT of breast cancer with a skin sparing close to that of orthovoltage EBRT at 320 kVp. SR-EBRT at low energy (60–80 keV) might be coupled to gold nanoparticles injection for dose-enhanced breast SR-EBRT. Disclosure Nothing to declare.

It is shown that an extensive set of accurate ionization-chamber measurements with a primary polychromatic synchrotron X-ray beam transmitted through various filter combinations/thicknesses can be used to quite effectively estimate the absolute flux distribution. The basic technique is simple but the `inversion' of the raw data to extract the flux distribution is a fundamentally ill-posed problem. It is demonstrated, using data collected at the Imaging and Medical Beamline (IMBL) of the Australian Synchrotron, that the absolute flux can be quickly and reliably estimated if a suitable choice of filters is made. Results are presented as a function of the magnetic field (from 1.40 to 4.00 T) of the superconducting multi-pole wiggler insertion device installed at IMBL. A non-linear least-squares refinement of the data is used to estimate the incident flux distribution and then comparison is made with calculations from the programsSPECTRA,XOPandspec.exe. The technique described is important not only in estimating flux itself but also for a variety of other, derived, X-ray properties such as beam quality, power density and absorbed-dose rate. The applicability of the technique with a monochromatic X-ray beam for which there is significant harmonic contamination is also demonstrated. Whilst absolute results can also be derived in this monochromatic beam case, relative (integrated) flux values are sufficient for our primary aim of establishing reliable determinations of the percentages of the various harmonic components.

We present methodology for the first FTIR measurements of ferrocene using dilute wax solutions for dispersion and to preserve non-crystallinity; a new method for removal of channel spectra interference for high quality data; and a consistent approach for the robust estimation of a defined uncertainty for advanced structural χr2 analysis and mathematical hypothesis testing. While some of these issues have been investigated previously, the combination of novel approaches gives markedly improved results. Methods for addressing these in the presence of a modest signal and how to quantify the quality of the data irrespective of preprocessing for subsequent hypothesis testing are applied to the FTIR spectra of Ferrocene (Fc) and deuterated ferrocene (dFc, Fc-d10) collected at the THz/Far-IR beam-line of the Australian Synchrotron at operating temperatures of 7K through 353K.

Using the far-infrared beamline of the Australian Synchrotron, the spectrum of the ν 7 band of ethylene- cis -1,2- d 2 ( cis -C 2 H 2 D 2 ) was recorded in the 640–990 cm −1 region at an unapodized resolution of 0.00096 cm −1 . A rovibrational analysis of a total of 2823 infrared transitions of the ν 7 band was carried out using an asymmetric rotor fitting program based on the Watson’s A -reduced Hamiltonian in the I r representation to derive up to four sextic constants with a rms deviation of 0.00035 cm −1 . From the fitting of 2634 ground state combination differences (GSCDs) of cis -C 2 H 2 D 2 which were derived from the infrared transitions of the ν 7 band of this work, and ν 10 and ν 12 bands of previous studies, together with 22 microwave frequencies, accurate ground state constants of cis -C 2 H 2 D 2 up to four sextic terms were obtained. The rotational constants ( A , B , and C ) of the v 7 = 1 state of cis -C 2 H 2 D 2 were found to agree within 0.5% with the calculated values using B3LYP/cc-pVTZ and MP2/cc-pVTZ levels of theory. From this work, the band center of ν 7 at 842.209489(20) cm −1 and the rovibrational constants of the v 7 = 1 state of cis -C 2 H 2 D 2 were determined with better accuracy than previously reported.

Micro-CT imaging of samples of metallurgical coke was achieved at high resolution (~ 10 μm), using the Imaging and Medical Beamline of the Australian Synchrotron. The coke samples were then stressed to breaking point and imaged again. The result is that we can examine, in fine detail in 3D, the locations of the fracture surfaces in the coke, and their relationship to the different aspects of the microstructure. In addition, we have performed 3D finite element linear elasticity analysis, using the microstructure of the cokes as input to the calculations. The result is a 3D map of the von Mises stress in the structure, which provides information about the likely locations of fracture. Finally, we have performed a fractographic analysis of the fracture surfaces, in order to characterise the nature of the fracture mechanisms. The imaging and analysis has been performed for both compressive and mixed-mode loading of the coke samples. The work provides the opportunity to identify the key mechanisms for fracturing of coke due to the aspects of their microstructure, and has the potential to aid in the production of stronger metallurgical coke, by means of blending coals to produce coke with improved strength properties.

Microbeam Radiation Therapy (MRT) exploits tumour selectivity and normal tissue sparing with spatially fractionated kilovoltage X-ray microbeams through the dose volume effect. Experimental measurements with Ta 2 O 5 nanoparticles (NPs) in 9L gliosarcoma treated with MRT at the Australian Synchrotron, increased the treatment efficiency. Ta 2 O 5 NPs were observed to form shells around cell nuclei which may be the reason for their efficiency in MRT. In this article, our experimental observation of NP shell formation is the basis of a Geant4 radiation transport study to characterise dose enhancement by Ta 2 O 5 NPs in MRT. Our study showed that NP shells enhance the physical dose depending microbeam energy and their location relative to a single microbeam. For monochromatic microbeam energies below ∼70 keV, NP shells show highly localised dose enhancement due to the short range of associated secondary electrons. Low microbeam energies indicate better targeted treatment by allowing higher microbeam doses to be administered to tumours and better exploit the spatial fractionation related selectivity observed with MRT. For microbeam energies above ∼100 keV, NP shells extend the physical dose enhancement due to longer-range secondary electrons. Again, with NPs selectively internalised, the local effectiveness of MRT is expected to increase in the tumour. Dose enhancement produced by the shell aggregate varied more significantly in the cell population, depending on its location, when compared to a homogeneous NP distribution. These combined simulation and experimental data provide first evidence for optimising MRT through the incorporation of newly observed Ta 2 O 5 NP distributions within 9L cancer cells.

Microbeam Radiation Therapy (MRT) is an emerging cancer treatment modality characterised by the use of high-intensity synchrotron-generated x-rays, spatially fractionated by a multi-slit collimator (MSC), to ablate target tumours. The implementation of an accurate treatment planning system, coupled with simulation tools that allow for independent verification of calculated dose distributions are required to ensure optimal treatment outcomes via reliable dose delivery. In this article we present data from the first Geant4 Monte Carlo radiation transport model of the Imaging and Medical Beamline at the Australian Synchrotron. We have developed the model for use as an independent verification tool for experiments in one of three MRT delivery rooms and therefore compare simulation results with equivalent experimental data. The normalised x-ray spectra produced by the Geant4 model and a previously validated analytical model, SPEC, showed very good agreement using wiggler magnetic field strengths of 2 and 3 T. However, the validity of absolute photon flux at the plane of the Phase Space File (PSF) for a fixed number of simulated electrons was unable to be established. This work shows a possible limitation of the G4SynchrotronRadiation process to model synchrotron radiation when using a variable magnetic field. To account for this limitation, experimentally derived normalisation factors for each wiggler field strength determined under reference conditions were implemented. Experimentally measured broadbeam and microbeam dose distributions within a Gammex RMI457 Solid Water® phantom were compared to simulated distributions generated by the Geant4 model. Simulated and measured broadbeam dose distributions agreed within 3% for all investigated configurations and measured depths. Agreement between the simulated and measured microbeam dose distributions agreed within 5% for all investigated configurations and measured depths.

Bright synchrotron x-ray sources enable imaging with short exposure times, and hence in a high-speed image sequence. These x-ray movies can capture not only sample structure, but also how the sample changes with time, how it functions. The use of a synchrotron x-ray source also provides high spatial coherence, which facilitates the capture of not only a conventional attenuation-based x-ray image, but also phase-contrast and dark-field signals. These signals are strongest from air/tissue interfaces, which means that they are particularly useful for examining the respiratory system. We have performed a range of x-ray imaging studies that look at lung function, airway surface function, inhaled and instilled treatment delivery, and treatment effect in live small animal models [Morgan, 2019]. These have utilized a range of optical set-ups and phase-contrast imaging methods in order to be sensitive to the relevant sample features, and be compatible with high-speed imaging. For example, we have used a grating interferometer to measure how the airsacs in the lung inflate during inhalation, via changes in the dark-field signal [Gradl, 2018], a single-exposure, single-grid set-up to capture changes in the liquid lining of the airways [Morgan, 2015] and propagation-based phase contrast to image clearance of inhaled debris [Donnelley, 2019]. Studies have also utilized a range of analysis methods to extract how the sample features change within a time-sequence of two-dimensional projections or three-dimensional volumes. While these imaging studies began in large-scale synchrotron facilities, we have recently performed these kinds of studies at an inverse-Compton-based compact synchrotron, the Munich Compact Light Source (MuCLS) [Gradl, 2018b]. 1. Morgan, Kaye, et al., “Methods for dynamic synchrotron X-ray imaging of live animals.”, under review 01/2019. 2. Gradl, R., et al. "Dynamic in vivo chest x-ray dark-field imaging in mice." IEEE Transactions on Medical Imaging (2018). 3. Morgan, Kaye S., et al. "In vivo X-ray imaging reveals improved airway surface hydration after a therapy designed for cystic fibrosis." American Journal of Respiratory and Critical Care Medicine 190.4 (2014): 469-472. 4. Donnelley, Martin, et al. "Live-pig-airway surface imaging and whole-pig CT at the Australian Synchrotron Imaging and Medical Beamline." Journal of Synchrotron Radiation 26.1 (2019). 5. Gradl, Regine, et al. "In vivo Dynamic Phase-Contrast X-ray Imaging using a Compact Light Source." Scientific Reports 8.1 (2018b): 6788.

THz synchrotron spectroscopy has become an important tool in the identification and quantification of molecular species of astrophysical interest; it is a routinely used technique as it is well established that synchrotron radiation offers a S/N advantage over conventional thermal sources. The brightness advantage is perfectly suited for high-resolution gas-phase spectroscopy, and at the Australian Synchrotron, this advantage is limited to energies lying below 1500 cm-1; however, a flux advantage is maintained for energies below 350 cm-1 which facilitates the study of homogeneous condensed-phase samples. The THz/Far-IR beamline is equipped with a suite of both gas-phase and condensed-phase techniques to enable research on interstellar molecular species, and in this paper, the beamline capabilities available for the study of molecular species of astrophysical interest will be presented.

PURPOSE Propagation-based phase-contrast computed tomography (PB-CT) is a method for three-dimensional x-ray imaging that utilizes refraction, as well as absorption, of x rays in the tissues to increase the signal-to-noise ratio (SNR) in the resultant images, in comparison with equivalent conventional absorption-only x-ray tomography (CT). Importantly, the higher SNR is achieved without sacrificing spatial resolution or increasing the radiation dose delivered to the imaged tissues. The present work has been carried out in the context of the current development of a breast CT imaging facility at the Australian Synchrotron. METHODS Seven unfixed complete mastectomy samples with and without breast cancer lesions have been imaged using absorption-only CT and PB-CT techniques under controlled experimental conditions. The radiation doses delivered to the mastectomy samples during the scans were comparable to those approved for mammographic screening. Physical characteristics of the reconstructed images, such as spatial resolution and SNR, have been measured and compared with the results of the radiological quality assessment of the complete absorption CT and PB-CT image stacks. RESULTS Despite the presence of some image artefacts, the PB-CT images have outperformed comparable absorption CT images collected at the same radiation dose, in terms of both the measured objective image characteristics and the radiological image scores. The outcomes of these experiments are shown to be consistent with predictions of the theory of PB-CT imaging and previous reported experimental studies of this imaging modality. CONCLUSIONS The results presented in this paper demonstrate that PB-CT holds a high potential for improving on the quality and diagnostic value of images obtained using existing medical x-ray technologies, such as mammography and digital breast tomosynthesis (DBT). If implemented at suitable synchrotron imaging facilities, PB-CT can be used to complement existing imaging modalities, leading to more accurate breast cancer diagnosis.

Microbeam radiation therapy is a novel pre-clinical external beam therapy that uses high-brilliance synchrotron X-rays to deliver the necessary high dose rates. The unique conditions of high dose rate and high spatial fractionation demand a new class of detector to experimentally measure important beam quality parameters. Here we demonstrate the highest spatial resolution plastic scintillator fibre-optic dosimeter found in the literature to date and tested it on the Imaging and Medical Beam-Line at the Australian Synchrotron in a X-ray beam where the irradiation dose rate was 4435 Gy/s. With a one-dimensional spatial resolution of 10 μm the detector is able to resolve the individual microbeams (53.7 ± 0.4 μm wide), and measure the peak-to-valley dose ratio to be 55 ± 17. We also investigate the role of radioluminescence in the optical fibre used to transport the scintillation photons, and conclude that it creates a significant contribution to the total light detected.

© 2018 Elsevier B.V. A distributed beam loss monitoring system, named the optical fibre Beam Loss Monitor, has been installed at the Australian Synchrotron. Relativistic charged particles produced in beam loss events generate photons via the Cherenkov mechanism in four silica fibres that run parallel to the beam pipe and cover the majority of the accelerator's length. These photons are then guided by the fibres to detectors located outside of the accelerator tunnel. By measuring the time of flight of these photons, the locations of beam losses can be reconstructed. Based on this method a calibration was produced, mapping the time of flight to a position along the accelerator. This calibration was applied to loss signals collected on the first pass of the beam through the accelerator and the locations of prominent losses were determined. Using this system it was possible to investigate the effect, on the location and intensity of losses, in response to changes in the lattice parameters on a shot-by-shot basis. This system is now used in routine operations and has resulted in a 40 % increase in the capture efficiency of the booster ring.

Microbeam radiotherapy (MRT) appears to target tumour cells while sparing normal healthy cells. However, it is in its preclinical stage at present. Clinical trials of MRT can be done in the Imaging and Medical Beamline (IMBL) of the Australian Synchrotron provided that the dose rate deliverable by the X-ray beam in Hutch 3B of the IMBL, where the required patient positioning equipment is located, is sufficiently high for MRT. At present the deliverable dose rate there is only 75 Gy s − 1 . However, a deliverable dose rate of between and including 375 Gy s − 1 and 750 Gy s − 1 is required for doing MRT clinical trials in Hutch 3B due to the irradiation profile inherent to MRT. The height of the focused beam in Hutch 3B must also be between and including 1.0 mm and 10 mm. A kinoform compound refractive lens (kinoform CRL) made of [ 3 . 5 × 1 0 18 P atoms c m − 3 ]-doped Si is proposed to be used in the Scenario where the X-ray beam, produced by a superconducting multipole wiggler source (SCMPW) operating at a maximum magnetic field of 4.000 T, is filtered by 0.6 mm of diamond before reaching the kinoform CRL. This is the Diamond-Optic Scenario. In this Scenario, the dose rate deliverable in Hutch 3B using the optic ranges from 380 Gy s − 1 to 1300 Gy s − 1 with beam heights ranging from 3.55 mm down to 1.0 mm, respectively. Also, the weighted average photon energies of the beam in Hutch 3B in this Scenario are almost entirely suitable for MRT in the IMBL. The X-ray beam in this Scenario can heat the P-doped Si optic to a few hundred degrees Kelvin above the hypothesised melting point of the P-doped Si due to its high power density. Therefore, the optic must be cooled lest it melt. The Diamond-Optic Scenario is not used routinely in the IMBL due to its excessive power. A variation of the Diamond-Optic Scenario, namely that the kinoform CRL be placed before sensitive components instead of after them is proposed for the routine use of this Scenario.