The project had 5 main work packages, each with their own specific objectives.
WP1 is project management. Regular meetings were held with the research supervisor, and progress regularly assessed. In some cases, covid-19 related delays forced some rescheduling of the work plan. However, we successfully implemented the project goals.
WP2 is for developing high repetition rate diagnostics for the laser driven ion sources. I successfully implemented a scintillator based beam profile monitor, which was delivered and worked extremely well on the experiment. This diagnostic allowed us to measure the angular divergence of the ion beam generated by our ion source. The technique used is novel and is being prepared for publication. I also implemented a new femtosecond optical probing system. This allowed me to take time resolved measurements of the ion acceleration process within the lifetime of the driver, something which has never been achieved before for laser driven ion sources.
WP3 was to demonstrate ion generation from a long wave infrared driven gas jet, and to investigate the mechanisms by which the ions were generated. This work was successfully performed, and a new regime of ion acceleration observed, in which electrons accelerated by the laser formed a diffuse sheath at the rear of the gas jet. This resulted in very stable and reliable ion generation, which is important for applications. Furthermore, the optical probing diagnostic developed in WP2 allowed us to measure the ion acceleration process in real-time, for the first time. I recreated the experiment using state-of-the-art particle-in-cell simulations, which agreed excellently with the experiment. These results are currently being prepared for publication in a high impact journal.
WP4 was to investigate the acceleration of ions from long wave infrared driven solid targets. Due to covid-19 delays and travel restrictions, some change to the workplan here was required. I was unable to access the long wave infrared laser facility for this experiment, so instead I performed a related experiment at a different facility. A near-infrared laser was used to drive ion acceleration from thin targets. I was able to demonstrate record ion energies for the laser type, and used particle-in-cell simulations to elucidate the acceleration process. I am first author on a publication of this work, which is in press at Light | Science and Applications (IF 20.26) and has caused considerable excitement in my research community. At the same time, planning work was performed for the long wave infrared driven solid target experiment and an experiment will be performed soon (after the end of the project) to investigate the interaction.
WP5 was for dissemination and communication of the work. During the project, I had invited talks at some of the top conferences in my field, including the 63rd Annual Meeting of the American Physical Society - Division of Plasma Physics 2021 (8th November 2021), the 5th European Advanced Accelerator Concepts Workshop (21st September 2021), and the International Conference on High Energy Density Science 2021 (4th April 2021). I have further invites for upcoming conferences based on work performed during the project. I created a webpage to describe the project. I have had one first author publication accepted at Light | Science and Applications (IF 20.26) and two more in preparation.
