THz Wave Accelerating Cavity for ultrafast science

Particle accelerators are devices of primary importance in a large range of applications such as fundamental particle physics, nuclear physics, light sources, imaging, neutron sources, transmutation of nuclear waste. They are also used every day for cargo inspection, medical diagnostics and radiotherapy worldwide. Electron is the easiest particle to produce and manipulate, resulting in an unequaled energy over cost ratio. However, there is an urgent and growing need to reduce the footprint of accelerators in order to lower their cost and environmental impact, from the future high-energy colliders to the portable relativistic electron source for industrial and societal applications. The radical new vision we propose will revolutionize the use of accelerators in terms of footprint, beam time delivery and electron beam properties (stability, reproducibility, monochromaticity, femtosecond-scale bunch duration), which is today only a dream for a wide range of users. We propose developing a new structure sustaining the accelerating wave pushing up the particle energy, which will enable democratizing the access to femtosecond-scale electron bunch for ultrafast phenomena studies. This light and compact accelerator, for which we propose breaking through the current technological barriers, will open the way towards compact industrial accelerators with an energy gain gradient of more than 100 MeV/m and enlarge time access in the medical environment (preclinical and clinical phase studies). This new accelerating structure will be combined with a conventional femtosecond-scale electron source, to provide a compact layout based on a multi-skill competence (non linear optics, High power optical source, accelerators, dosimetry) secured by industry partners. Its size and weight will for example enable it to be mounted on a robotic arm, to move around a patient for medical applications or material inspection for industrial applications.