Kilohertz-rate plasma photocathode wakefield acceleration

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Plasma wakefield accelerators (PWFA) catapult electrons to tens of Giga-electron-volt energies on metre-scale distance - which would otherwise require multi-km-scale conventional accelerators. In addition, plasma photocathodes have been invented in order to exploit the enormous electric fields in plasmas also to produce electron beams which are 100,000x brighter that state-of-the-art. These can be realized at linac-powered plasma wakefield accelerators as well as at hybrid laser-plasma-accelerators. Plasma photocathodes and preionization stages can be developed and operated by state-of-the-art pulsed laser systems with kilohertz repetition rates, as they do not require the power levels that can be produced only by large, highest power laser systems which operate at sub-10 Hz repetition rates. A combined longer-term goal of these R&D thrusts - each transformative in its own right - is the production of plasma-based electron beams which are 100,000x brighter, 1000x stronger at repetition rates 100x higher than state-of-the-art. The studentship will explore fundamental laser-plasma-physics underlying the operation of plasma accelerators and plasma photocathodes at kilohertz repetition rates. The plasma photocathode afterglow signature will be investigated to explore the recombination and expansion dynamics, and will be exploited for metrology of the interaction process. SCAPA's in-house capabilities will be exploited to address these questions, complemented by experiments at above mentioned linac-powered facilities as well as at leading laser-plasma accelerator laboratories in Europe. Challenges and features of operating plasma accelerators by kilohertz systems at the power threshold e.g. for self-focusing and self-compression, such as high density plasma sources and strong spectral broadening and repeated laser pulse collapse, will be in the focus of the studentship. The above mentioned effects are expected to allow production of relativistic, broadband electron beams with energies up to a few MeV from the interaction of kilohertz-scale laser pulses with plasmas. Such an electron beam output flux is ideally suited for applications such as for space radiation reproduction and radiation hardness assurance of electronic components, e.g. satellite electronics, or for skin cancer treatment. Both applications are driven forward in collaboration with industry. We will demonstrate these technologies and applications at SCAPA, aiming to offer them to a wide range of industrial and medical users. The studentship will be co-funded by Research Center Julich in Germany. In Julich, a unique high-power, kilohertz laser system is available for laser wakefield acceleration and applications. This system, jointly with Strathclyde's kilohertz-laser pulse capabilities, provides a cutting-edge R&D environment for the studentship.