ISIS Excursion – a trip to a particle accelerator
In September last year, to celebrate the publication of Tom Whyntie and Oliver Pugh’s Introducing Particle Physics, we ran a competition, in association with Blackwells and the Rutherford-Appleton Laboratory, to win a rare visit to the ISIS particle accelerator at the laboratory near Didcot in Oxfordshire.
Dan Tucker, from Brighton, won the competition and on Sunday came along with friend Bryony to see for themselves exactly what Britain’s answer to the Large Hadron Collider looks like. Tom Whyntie came along to help explain some of the science involved and all four of us were extremely ably shown around the amazing facility by Dr. Dan Faircloth, Senior Research Engineer and Ion Source Section Head.
Here are some photos that I took along the way. I’ll try briefly to explain what’s going on in them!
This is the bridge over from the car park into the ISIS facility, in fact leading into Target Station 2, the second of two large warehouse or factory-like buildings holding the equipment enabling scientists to use the accelerator to test all sorts of materials, from aircraft wings to detergents.
It’s interesting to note that ISIS is a publicly-funding scientific institution, and, as Dr. Faircloth put it, free at the point of need like the NHS, it focuses primarily on practical questions and the practical application of particle physics. So while the science is extremely complex, its role is not primarily about investigating the fundamental building blocks of the universe.
Here’s Dan showing us the model of ISIS. The circle you can see lit up in red is the synchrotron, the main circular particle accelerator.
Inside Target Station 2. It was a Sunday but you get the sense that it’s always pretty quiet here, in terms of human noise at least. In many senses it looks like any big factory building.
The place was littered in machinery like this. Tom reckons there’s a big market for furniture constructed from leftover particle accelerator technology. Imagine these things on their sides as a coffee tables!
Love these enigmatic signs – this is what the future was supposed to look like, in about 1975…
The reason that we were allowed to look around the facility at all was that it’s currently in shutdown. The accelerator runs constantly, 24 hours a day, 7 days a week for periods of about 6 weeks, and then shuts down for a similar period for maintenance. This part is being checked over during the shutdown period.
Tom looks as happy as he takes photos amidst the maze of machinery in Target Station 1, the older of the two Target Stations!
Do you have a Muon Liquid Handling System where you work? No, us neither.
Safety is, as you might imagine, taken incredibly seriously throughout ISIS
The plaque unveiled by then Prime Minister Margaret Thatcher when ISIS was first opened in October 1985.
Target Station 1 as seen from one of the gantries along the edge
The synchrotron control room, looking pleasingly old-fashioned. Apparently this is going to be replaced soon by a more high-tech control facility along the lines of that at CERN, which is a shame, aesthetically speaking…
As this point we all had to clip radiation monitors to our coats. Radiation through the facility is rarely higher than the background radiation that we are all subjected to everyday from nature cosmic rays – but as I mentioned before, it’s safety first.
Another safety feature is the key-lock system. Inside that wire door Dan is opening there’s a bank of large bronze keys. You have to take one with you whenever you enter a restricted area – in this case, the ion source, where the particles used in the all of the research are first created – and the accelerator can’t be switched on until all of the keys are back in their locks just behind the door. Like a reverse version of the two keys needed to launch a nuclear missile.
Here’s Dan with the device that, using hydrogen gas and caesium vapour, creates the H- ions that ISIS uses. It’s all very high-engineering but amazing that this is the heart of the huge facility – there’s no point in any of the other parts in the building if this section isn’t functioning properly. This area is what Dan is specifically responsible for.
The ISIS synchrotron is actually something of a mongrel – it was constructed, in a fantastically British Heath Robinson style, from other bits of older accelerators. This part, one of the oldest, was as you can see made by Vickers, which you might know from aircraft such as the Spitfire…
More brilliant buttons
Now we’re into the circular building holding the synchrotron accelerator itself. When the accelerator is running, the radiation levels would be too high for humans to safely enter, and it’s left to run all alone… Each of the boxes surrounding the accelerator tube are responsible for speeding the H- ions circulating around it up, or bending their path with huge magnets so that they travel in a circle.
It was strangely deceptive experience, walking around this circular building with so much to look at but it all being both rather mysterious and yet samey. We all thought it was bizarre when we realized that we were back at the start of the circle where we’d come into the building.
There were frequent signs indicating the radiation levels at certain points around this building, like this one.
More cool heavy machinery and switches. Who needs a mouse and Windows when you have stuff like this to operate everyday?
This is a much newer section of accelerator, leading particles back into Target Station 2 for use in experiments.
Press this in emergencies!
The delightfully pink exterior of one of the modules which use the product of the accelerator to test materials.
And that was it! After the trip itself Tom, Dan, Dan, Bryony and I headed into Oxford for a late lunch at the Kings Arms, conveniently next to Blackwell’s wonderful Broad Street shop.
Thanks to Blackwells for running the competition with us, to everyone who entered, to Tom Whyntie for support and knowledge and enthusiasm (and this song, about the banana equivalent, a unit of calibration for radiation based on the amount of radiation in a banana) and most of all to ISIS and Dr. Dan Faircloth for sharing his enthusiasm and knowledge with us scientific-ignorami (and Tom!).