NEG Coatings and their Potential to Make a Major Impact on Future Advanced Particle Accelerators

Applications are invited for an exciting opportunity to study for a 3.5-year PhD commencing Oct 2019 on the development of technologies that are critical for future particle accelerators. Non-evaporable getter (NEG) coating, originally invented at CERN, is already used in many accelerators due to three main properties: (1) it reduces thermal and photon, electron and ion induced gas desorption acting as a barrier between a vacuum chamber material and an inner vacuum; (2) a fully coated vacuum chamber has large distributed pumping speed, the benefit of this is essential for the narrow vessels with a limited vacuum conductance; (3) the NEG coating has low secondary electron (SEY) yield that helps to supress electron multipacting and electron cloud in high intensity accelerators. NEG coating is the most promising and most economic solution for a vacuum system of the next generation accelerators. ASTeC, world leader in this area, is working on optimisation of NEG on optimising all three NEG coating benefits. Further development of this technology require working on interdisciplinary field: accelerator, material and vacuum science. There are two main challenges in further NEG coating optimisation: (1) the beam impedance in the NEG coated chamber, which related to beam parameters and NEG coating resistance, this is a problem for short-bunch machines; (2) coating of NEG on narrow tubes with a diameter less than 10 mm, this is a problem for small aperture machines like a future UK-XFEL.