‘Cleaning’ to unlock stars’ secrets Yorkshire academics’ help work on particle accelerator
It would be disastrous. The LHC would be shut down for months.
Professor Barlow on what would happen if a particle beam damaged the collider
IT IS hailed as the most powerful physics experiment ever built, and recreates the conditions just after the Big Bang in an attempt to answer fundamental questions about the nature of the universe.
But despite the billions of pounds worth of investment in the Large Hadron Collider (LHC), based at a laboratory near Geneva, in Switzerland, there’s always the risk of something going wrong.
An errant beam of accelerated particles, fired in opposite directions with the help of hugely powerful magnets, could cause serious damage to the structure of the pioneering system, disastrously closing it down for months, if it veers away from its true path.
Devices known as collimators, made of two opposing jaws about 1.2 metres in length that sit near to the beam, are key to stopping this from happening by using a technique described as ‘cleaning’ the particles.
And now two academics from a Yorkshire university have been awarded funding worth hundreds of thousands of pounds to carry out work on a vital upgrade to LHC’s collimators in a scheme that could increase the amount of data its experiments can gather in their search for new particles.
Professor Roger Barlow, a leading particle physicist who heads the International Institute for Accelerator Applications at the University of Huddersfield, has been carrying out computer simulations of the LHC’s collimation system with academics from Manchester.
When the UK’s Science and Technologies Facilities Council (STFC) began to collaborate with CERN (the European Organization for Nuclear Research) on the LHC’s luminosity upgrade, Professor Barlow was enlisted to develop programs and simulations that would help the development of new collimators.
He knew that an ideal candidate to lead the design and manufacture of a prototype collimator would be Dr Simon Fletcher, of the Engineering Control and Machine Performance Research Group that is part of the University of Huddersfield’s Centre for Precision Technology.
Known for applying novel techniques to real world problems, the Huddersfield base is one of only 16 national centres for innovative manufacturing in the UK.
Professor Barlow and Dr Fletcher have now been awarded a total of £639,336, made up of contributions from both STFC and CERN, to carry out work on the vital LHC upgrade and Dr Fletcher has now embarked on a three-year work package that will lead to the production of a new collimator prototype. According to Dr Barlow, it would be a “disaster” if the high amplitude particles being fired around the LHC impacted on its ‘cold mass’. “The whole LHC would be shut down for many months,” he said. Collimators have to be manufactured from material such as carbon fibre reinforced carbon composite that can absorb radiation since their role is to “tidy up” stray particles, and for this they have to be absolutely straight and parallel.
To ensure this, Dr Fletcher plans a switch from a passive to an active system for the LHC’s collimators.
“Simulations and operational experience show that the jaws can lose their straightness over long operating periods and during highly energetic impact events, which affects the performance and the efficiency.
“We are therefore proposing to add sensors that pick up any distortion and we will design and install some actuators that will then deform the jaws to make them straight again.”
A research assistant will be appointed to work with Dr Fletcher on the collimator design and the successful candidate will spend a large part of their time at CERN in Switzerland.
The prototype collimator will be designed and built at the University of Huddersfield using in-house machining and metrology facilities, along with specialist local advanced manufacturing firms.