Speeding up synchrotron x-ray fluorescence imaging
Synchrotron x-ray fluorescence (SXRF) imaging is a powerful technique used in the biological, geological, materials and environmental sciences, medicine and cultural heritage.
The technique harnesses the spectrally pure and finely focused x-ray beam from a synchrotron microprobe beamline. Digital images of microscopic or nanoscopic detail are built, pixel by pixel, by scanning the sample through the beam.
The resulting x-ray fluorescence radiation is characteristic of the chemical elements in that pixel. This is used to quantify the chemical composition of the sample, including important trace elements, and to build up element images of the sample.
Although powerful, synchrotron SXRF imaging is traditionally slow, often just a few pixels per second. Its pixel-by-pixel nature, low sensitivity and slow readout of conventional x-ray detectors, and the significant data processing task severely limits the size of images that can be made during a researcher's limited synchrotron time; images of just 200 x 200 pixels sometimes take hours.
High resolution, real-time imaging
We worked with the Brookhaven National Laboratory (BNL) in New York to develop the Maia x-ray microprobe detector system. The system combines BNL's custom detector arrays and application-specific integrated circuits, with our high-speed data capture hardware and real-time spectral analysis algorithms.
The Maia system is a high-throughput x-ray fluorescence detector and real-time analysis system that allows samples to be scanned up to 1000 times faster and in much greater detail than previous methods.
This system, when combined with a focused x-ray source – such as the Australian Synchrotron's x-ray fluorescence microprobe (XFM) beamline – is able to produce high-definition, quantitative element images with microscopic detail in real-time.
Its large detector array and real-time processing capacity allow trace elements to be mapped very rapidly at micron resolution and over centimetre scales. It can produce detailed hyperspectral images beyond100 million pixels in size.
In 2011, Maia won a prestigious R&D 100 Award, presented by the US-based R&D Magazine, 'to salute the 100 most technologically significant products from around the world introduced into the marketplace in the past year'.
Users of the XFM beamline have used the Maia to tackle research spanning biological, geological and environmental sciences, material science, medicine and mineral exploration and processing.
A world-leading research tool
The Maia detector is now installed at four synchrotrons globally, serving the high definition trace element imaging needs of hundreds of research users.
It's transformed trace element imaging for the minerals exploration industry, providing unprecedented detail and revealing rare precious metal clues and trace element indicators in exploration and ore deposit samples.
For example, using Maia we can actually see the distribution of low-level trace gold in our samples. Being able to map large areas quickly enables us to look for the hidden gold across the sample, and beneath its surface, including places places we would have never looked at before. XFM is also being used to detect rare platinum group minerals in samples. These elements are exploration pathfinders for nickel ore deposits formed from mantle-derived magmas.