A Roadmap for Plasma Wakefield Acceleration
Plasma wakefield accelerators rely on laser- or particle beam-driven intense plasma waves as accelerating medium, with electric fields 1000 times stronger than in conventional accelerators. This opens pathways to reduce the size of accelerators from the km-scale to the metre-scale, and to realize and explore previously inaccessible output beam parameter regimes. A quickly growing worldwide community with research thrusts across disciplines such as accelerator, laser and plasma physics is developing this technology to increasing maturity. The expectation is that this will have transformative impact on fundamental tools and applications for natural, material and life sciences, for example by realization of compact, bright, and coherent x-ray sources.
In order to manage this development, and to identify the key advances in science and technology which will be required, the UK Plasma Wakefield Accelerator Steering Committee (PWASC) has compiled a community-driven roadmap (https://arxiv.org/abs/1904.09205) for the development of plasma wakefield acceleration over the next 20 years.
The roadmap gives an overview on state-of-the-art of the different flavours of plasma wakefield accelerators, and uses national and international perspectives to identify and highlight key scientific and technological R&D topics and applications. The broad range of applications across research council remits and disciplines, and their importance in context of the UK’s industrial strategy is analysed and discussed. As such, the roadmap is complementary to the 2017 STFC Accelerator Strategic Review Report: While the “Novel Acceleration” theme of the earlier report looked at various high-gradient accelerator technologies predominantly from an STFC perspective, the PWASC Roadmap focuses on the important subset of plasma wakefield accelerators specifically from a cross-council perspective. The Roadmap develops a timeline of key developments, and derives 10 key recommendations which shall aid research councils and agencies and stakeholders in decision making.
An over-arching finding is that while the UK has a strong track record of conceptual and experimental leadership in the field, a concerted cross-council R&D programme is now required in order to realize the applications of plasma accelerators and to maximize both their impact and the return on previous UK investment in this research field.