El domingo 20 de octubre algunos socios de SRAP-IEAP en Melbourne disfrutaron de una visita al Australian Synchrotron. El siguiente artículo, escrito por Graeme Hosking y sólo disponible en inglés, da un resumen de la visita.
Article written by Graeme Hosking.
In an unremarkable corner of a Melbourne suburb, perched on the edge of Monash University’s Clayton campus, sits one of the most remarkable devices built by modern man. Filling a building bigger than most aircraft hangars, the Australian Synchrotron is one of the largest tools in existence, and the only one of its kind in Australia.
The enormous size and highly technical nature of the synchrotron make it a highly mysterious thing. However, perhaps in an attempt to dispel any “mad science” conspiracy theories, the institute which manages the facility holds annual Open Days, at which members of the public can take an informative tour around and even inside the synchrotron, hosted by enthusiastic members of the research team who work there.
Which is why, one fine 20th October Day, SRAP-IEAP in Melbourne (and a few hangers on) attended the Open Day to explore the synchrotron, and find out more about it, and what it does.
Its uniqueness means that it is possible to describe it only in ways that oversimplify it – “It’s a giant lightbulb” – or which capture only how it works – “it accelerates and focuses light through applying massive amounts of energy”. After staring open-mouthed at the sheer size of the thing, we managed through charm and cunning to get onto a tour of the interior of the machine. This involved climbing up over two storeys and down again, and then into the circular tunnels (the “booster” and “storage” rings) around which supercharged electrons race when the machine is on.
We were lucky enough to be hosted by one of the senior leaders of the facility, a tall thin, bearded gentlemen with glasses and an East European accent. His passion for the topic was infectious, and he was constantly overrunning his allotted time in explaining things to us, and then being moved on by a “minder” who was there to keep the tour on time.
We started our tour at the electron gun, which heats a barium compound cathode to 1000C, generating electrons which are then pushed out with a 90,000 volt charge. That’s only the start of the process though. The Linear Accelerator and the Booster Ring come next, and these zap the electrons up to 99.9987% of the speed of light using a combination of very high frequency radio waves, and a further 3 billionvolts of electricity. At this enormous speed, the electrons complete 1 million laps of the booster ring in half-a-second, which sounded quite fast to us.
Luckily the device was off when we were inside it. It generates no x rays (unlike the large hadron collider, its bigger brother in Europe) – but the very high levels of energy involved would surely cause some damage to any living human being inside it. We were impressed by the huge amount of engineering involved: thousands of kilometres of wiring, piping, and magnets. Everywhere, magnets. If you want to bend high speed electrons to go round corners, apparently you need magnets. Like a very much larger version of an MRI machine perhaps, and it does indeed generate the kind of medical imaging beams that an MRI does, but on a vastly more powerful level.
After we stumbled out of the synchrotron itself, minds totally boggled, we wandered around the outside of the rings, where 10 stations had been set up to manage the different kinds of energy outputs produced by the synchrotron. For the Open Day, the facility staff had helpfully set out examples of the kinds of materials examined by the different energy beams – from medical imaging, through X ray fluorescence microscopy, micro crystallography, infrared spectroscopy, powder diffraction…. By the end of the tour, we were in no doubt that this incredibly powerful source of high-energy electrons had an enormously large number of potential uses, from medicine through to a wide range of materials science research.
It’s rare that we get a chance to see up-close something which can only be described as Big Science, and it didn’t disappoint. Maybe the whole thing on the inside was not as shiny as it appears in the movies (apart from the strange device called a “Tesla Wiggler”, we’re still wondering about that…). But it was an impressive and informative day out, and for that we would like to thank the Australian Synchrotron staff and guides, for doing such an excellent job in sharing their amazing facility with us and other appreciative members of the Melbourne public.