Announcements

We are pleased to announce that the Best Presentation Awards, sponsored by Condensed Matter for “High Precision X-ray Measurements 2021”, were granted to Dr. Elette Engels, Dr. Ginevra Begani Provinciali and Dr. Bharat Mishra. Congratulations! 

Mastering Synchrotron Microbeams for Radiotherapy: Effective Cancer Treatment with Remarkable Healthy Tissue Tolerance

Elette Engels
University of Wollongong

This research explores the efficacy of the synchrotron X-rays that are collimated into microbeams for cancer treatment. We have shown that Synchrotron Microbeam Radiation Therapy (MRT) has the potential to rapidly treat otherwise resistant cancers while sparing normal tissue. Our work at the Imaging and Medical Beam Line (IMBL) of the Australian Synchrotron integrated state-of-the-art radiation detectors to translate MRT from the quality assurance stage to treating cancers in vitro and in vivo. With a focus on the challenging cancers of the brain and lung, we have determined that the surrounding organs at risk (including the brain, spinal cord, and heart) could tolerate microbeam doses in the range of 400–800 Gy remarkably well. We further showed that microbeams effectively increased the survival of rats with resistant brain cancer by over 220%. This work was performed in collaboration with Dr. Elisabeth Schültke, (Rostock University Medical Center, Germany), the Centre for Medical Radiation Physics, Australian Synchrotron, Illawarra Health, and Medical Research Institute, and Prince of Wales Hospital (Australia). 

High Sensitivity X-ray Phase Imaging System Based on a Hartmann Wavefront Sensor

Ginevra Begani Provinciali
Laboratoire d’Optique Appliquée, CNRS, ENSTA Paris,Ecole Polytechnique IP Paris

We developed a new high-resolution 3D X-ray phase imaging system based on Hartmann wavefront sensing. The system provides high spatial sampling (20 μm without magnification) and high angular sensitivity (~100 nrad) over a 5 to 25 keV energy range. This setup has been coupled with tomography measurements to obtain a 3D reconstruction of the object. Remarkably, the X-ray Hartmann imaging system is capable of providing single-exposure quantitative measurements of both phase and amplitude without the need for any phase-retrieval procedure. Furthermore, to optimize the sensor design, we developed a 3D wave propagation model based on Fresnel propagator and partial coherent beams. 

Probing Electron Properties in ECR Plasmas using X-ray Bremsstrahlung and Fluorescence Emission

Bharat Mishra
INFN - LNS and Universita degli Studi di Catania

A quantitative analysis of X-ray emission from an electron cyclotron resonance (ECR) plasma was performed to probe the spatial properties of intermediate energy electrons. A series of measurements were taken by INFN-LNS and ATOMKI, capturing spatially and spectrally resolved X-ray maps, as well as volumetric emissions from argon plasma. Comparing the former with model-generated maps (involving space-resolved phenomenological electron energy distribution function and geometrical efficiency calculated using ray-tracing MC routine) furnished information on structural aspects of the plasma. Similarly, fitting a model composed of bremsstrahlung and fluorescence to the volumetric X-ray spectrum provided valuable insight into the density and temperature of confined and lost electrons. The latter can be fed back to existing electron kinetics models for simulating more relevant energies, consequently improving theoretical X-ray maps and establishing the method as an excellent indirect diagnostic tool for warm electrons, required for both fundamental and applied research in ECR plasmas.