Novel beam sensors built to last
A team of accelerator scientists is testing the use of new, more resistant sensors based on hollow glass fibres to measure particle beams
A slender glass fibre no thicker than a human hair placed across a particle beam could improve accelerator monitoring. A team is testing the use of hollow-core optical fibres to measure the profile and position of the beams extracted from the Super Proton Synchrotron, CERN’s second-largest accelerator, which feeds the experiments located in the North Area.
Unlike conventional fibres, which guide light through solid glass, hollow-core optical fibres are mostly empty inside but have a microstructure design that guides light through resonance–antiresonance effects on the electromagnetic field. By filling these fibres with a scintillating gas – a gas that emits tiny flashes of light when struck by particles – scientists can create a simple yet powerful radiation sensor that helps them to adjust the beam profile and position and may even allow them to measure the delivered beam dose in real time.Unlike the multi-wire proportional chambers and scintillator detectors currently used, these fibres can be used in an extreme radiation environment and are therefore very useful for CERN’s future accelerators and experiments.