Applications are invited for a Postdoctoral Research Assistant at the John Adams Institute for Accelerator Science. The post is available for a fixed-term duration of 24 months with the possibility of 12-month extension. The John Adams Institute for Accelerator Science at the University of Oxford and Diamond Light Source Ltd. are seeking a highly qualified post-doctoral research assistant to carry out research relevant to the Diamond-II synchrotron light source project. The successful candidate will work with members of the Diamond Accelerator Physics Group, investigating topics such as the impact of collective effects on beam stability and associated mitigation methods, commissioning of the injector complex and storage ring injection studies. The successful candidate will actively collaborate with other technical groups working on the design. The successful candidate will also have opportunity to conduct experiments and machine development activities on the existing accelerators. The key duties of the post include: Conduct in-depth simulations and analysis to model and understand the performance of the Diamond-II accelerators for both single and multi-particle effects; develop and apply advanced numerical simulation and/or optimization tools to the design and characterization of the facility; interact with other technical groups working on the Diamond-II design (e.g. Engineering, Diagnostics, Vacuum, RF, Power Supplies, Controls); contribute to producing the relevant procedures and high-level software tools in order to achieve the above; actively participate in machine development shifts, proposing and undertaking new experiments, carrying out the corresponding data analysis and reporting the findings to the Accelerator Physics and Machine Development meetings. Applicants should hold, or be close to completion of, a PhD/DPhil in accelerator physics, particle physics or a related field and have a solid background in beam dynamics, lattice design and beam transport studies. Candidates are expected to demonstrate the ability to: work as part of a team; identify research objectives and subsequently conceive, plan and independently execute appropriate activities to deadlines; communicate effectively both orally and in writing; be self-motivated and able to motivate and guide the work of others. Previous experience in the commissioning and operation of storage rings and knowledge of accelerator physics modelling codes such as Accelerator Toolbox or ELEGANT would be an advantage. The post-holder will have the opportunity to teach. This may include lecturing, small group teaching, and tutoring of undergraduates and graduate students. Please direct enquiries about the role to Professor Philip Burrows (philip.burrows@physics.ox.ac.uk). Only applications received promptly by 12:00 noon UK time on 30 January 2026 can be considered. You will be required to upload a CV, a description of relevant research experience and interests and the names and addresses of three referees as part of your online application. In addition, you should arrange for the letters of reference to be sent to ppadmin@physics.ox.ac.uk by the closing date. Applications are acknowledged but not reference letters. Please read the “Person Specification and Job Description” before preparing your application.