Jim joined Daresbury Laboratory in 1989 as an accelerator physicist and became the Group Leader for the Magnetics and Radiation Sources Group when it was created in 2002. In 2016 he was appointed the Head of Science Division for ASTeC, which includes the Accelerator Physics Group and the Lasers Group as well as his own group.  

He has worked on a wide variety of accelerator topics but has particular expertise in undulators, wigglers, and other magnets for accelerators. He is the author of a text book* published by Oxford University Press covering all aspects of undulators and wigglers. Jim has designed and built many undulators and wigglers that have been used successfully on a number of light sources. This interest led to him leading the International Linear Collider Positron Source Team for a number of years. He is currently active in the field of superconducting undulators for storage ring light sources and free electron lasers (FELs) and is exploring potential new RF-based undulator systems.  

Jim is the leader of the CLARA FEL Test Facility which is currently being built at Daresbury and also the leader of the UK XFEL Underpinning Technology ProgrammeJim is involved in all the research areas of his group, from FELs to fast pulsed kicker magnets to Wakefield calculations. One area in which he has a special interest in at the moment is the development of tunable permanent magnet-based dipoles and quadrupoles for the Compact Linear Collider (CLIC) at CERN which will save tens of MW of electrical power if fully implemented across CLIC. The group has taken out a patent on their novel quadrupole design.  

He is a Visiting Professor in the Department of Physics at the University of Liverpool.  

*The Science and Technology of Undulators and Wigglers, Oxford University Press, 2004​