Posted on: 10th October 2011
If you had spent sixty thousand euros on a new brick wall around your home, you would want to look after it. You might even install a security camera to prevent vandalism.
Swiss physicist Gilles Arnoux is in just such a situation, except that his wall cost 60 million euros and is made of beryllium. It lines the inside of JET, and was installed recently as a prototype for the international fusion reactor ITER, being built in the south of France. The vandal in question is a plasma at several thousand degrees Celsius, only centimetres away and threatening to escape its magnetic confines.
So Gilles, the section leader for viewing systems and thermal measurement at the Culham Centre for Fusion Energy, has designed and installed a surveillance system for the interior of JET, made up of nearly 20 cameras and heat sensors. It is coupled with a computer system and will detect irregularities in the plasma, such as hotspots on the wall. Within a tenth of a second , it will adjust the system to reduce damage, and, if needed, to terminate a plasma pulse.
Standing in the control room, dwarfed by a bank of live video feeds showing every conceivable angle of the inside of JET, Gilles smiles. “It was challenging, ambitious to complete it in one and a half years, but the team has been very dedicated.” he says. “It’s very rewarding now to see people’s reaction, they are excited when they see the new data screens!”