High power laser plasma acceleration – making accelerators smaller, cheaper, better

Applications are invited for a fully funded studentship from Oct 2025 in laser-driven plasma wakefield acceleration (LWFA). LWFA has been hugely successful in demonstrating high gradient and high energy acceleration of electrons but the shot-to-shot energy stability and bandwidth of these sources remains however below that of conventional accelerators; this is due to the intrinsically nonlinear and noisy nature by which particles are ‘self-injected’ into the laser wakefield. One attractive method to improve the performance of LWFA would be to inject high quality bunches from a conventional accelerator into a LWFA, which would allow energy gain in a linear regime and preserves the injected bunch quality. 

This project will build on initial experiments led by Dr. Corner at the CLARA accelerator at Daresbury Laboratory demonstrating the successful injection and acceleration of electrons in a laser driven plasma. Prediction, measurement and control of the electron beam properties before the plasma is fundamentally required to achieve high output beam quality. Improvements in synchronisation technology in order to both understand and deliver stable longitudinal injection. In order to validate the output beam quality, tools for the measurement of key beam properties – including emittance – must be considered. With these developments there is much scope available for future experiments to significantly increase both the accelerating gradient and charge captured in an external injection experiment, while fully preserving the beam quality during acceleration.

The new FEBE facility at the Daresbury Laboratory is a perfect test bed for these experiments, and nearly unique in this capability. This project aims to be a flagship demonstration of these capabilities combining the new 120TW laser and upgraded (250MeV) CLARA electron beam. This project aims to investigate both numerically and experimentally external injection of electrons into a laser driven wakefield at FEBE and develop diagnostics capable of fully characterising the accelerated beam. This will involve detailed simulations using the fbpic code and beam simulations in collaboration with AsTeC staff to identify the parameter space and associated tolerances for successful injection and acceleration. The project will build on a previous PhD project developing timing tools for the FEBE hutch and laser, implementing these to measure, understand and mitigate factors influencing temporal synchronisation.

Proposed Scheme of Work

The student will work initially experimentally on basic laser systems and laser physics, as well as attending CI graduate lectures to gain a broad understanding of accelerator physics. The student will work closely with ASTeC accelerator physics staff and use the results of their detailed start to end simulations of electron bunches delivered to FEBE as the input to simulations of external injection using the fbpic particle in cell code. This close collaboration with ASTeC staff is a key advantage of the Cockcroft Institute; most simulations use generic Gaussian distributions of electrons as input, but having access to detailed results from FEBE design studies will allow the student to perform more accurate simulations and fully optimise the injection experiment. The collaboration with ASTeC will also include working in the Accelerator Timing, Lasers and Synchronisation (ATLAS) Laboratory, to develop timing jitter measurement diagnostics to be implemented on the CLARA accelerator. The student will finally take a principal role in the planned experimental demonstration of external injection, including involvement in the implementation of suitable diagnostics.

Potential applicants are strongly encouraged to contact Dr. Laura Corner (laura.corner@liverpool.ac.uk) for more information. This position will remain open until filled but it is typical to interview students in Jan/Feb 25 for start in Oct 25 so interested candidates should submit applications before then.

Funding and eligibility: Upon acceptance of a student, this project will be funded by the Science and Technology Facilities Council for 3.5 years. This consists of a tax free stipend at UKRI rates (£18,677 for 23/24), university fees at the home (UK) rate, plus support for travel to conferences and workshops. A full package of training and support will be provided by the Cockcroft Institute, and the student will take part in a vibrant accelerator research and education community of over 150 people. An IELTS score of at least 6.5 is required.

Contact for further information: Dr. Laura Corner laura.corner@liverpool.ac.uk

How to apply: http://www.cockcroft.ac.uk/join-us

Anticipated Start Date: October 2025 for 3.5 Years