ULTRAfast exploration and control of electron bunch dynamics in SYNChrotron light sources

• Applicant: Professorin Dr. Anke-Susanne Müller
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 431704792

The ULTRASYNC project aims at observing, understanding and controlling ultrafast self-organisation of relativistic electron bunches in accelerator facilities. A central goal is to master the emission of giant pulses of terahertz (THz) Coherent Synchrotron Radiation (CSR) that occurs concomitantly in synchrotron radiation facilities and thus to propose new THz sources. Another intermediate and major milestone is to design novel ultrafast observation tools (in particular high acquisition rate “THz oscilloscopes”), which are critically needed - not only for ULTRASYNC - but also by the accelerator community in general. The project includes fundamental theoretical and experimental investigations at two accelerator facilities: SOLEIL (FRA), the French national light source, and KARA (GER), the electron storage ring of the KIT synchrotron radiation source. A main strength of the consortium comes from its optimal composition, both leaders in high repetition-rate ultrafast single shot measurements: KIT-LAS (GER), which hosts at KARA one of the only experiments in the world that can “probe” directly the shape of relativistic electron bunches in a storage ring facility, and the SOLEIL-PhLAM collaboration (FRA) who uses ultrafast photonic time-stretch and temporal imaging techniques. Experimental and theoretical/numerical investigations will be performed in parallel with the goal to understand the complex and non-linear dynamics of electron bunches. The newly acquired knowledge will be used for attempting to “tame” the CSR instabilities with two ambitious strategies: (i) at KARA, we will directly manipulate the interaction between electrons of the bunch, by developing experimental EM field manipulation structures, (ii) at SOLEIL, we will attempt to transfer techniques of chaos control (feedback control of periodic orbits), for achieving stable THz CSR emission. This project is interdisciplinary in nature, as it requires knowledge and capabilities in accelerator physics, non-linear dynamics (in storage rings, spontaneous CSR emission comes from instabilities), chaos control, laser and non-linear optics. This will be provided by a close interaction between specialists in laser, photonics, non-linear dynamics, and accelerator science. Parts of the project present a high level of risk, because they address largely unexplored research fields, such as cutting-edge detection techniques, non-destructive manipulation of relativistic particles, and dynamics of instabilities with extreme complexity. These risks are nevertheless limited by the formation of a consortium with unique and complementary know-how and history. These risks are also largely counterbalanced by the potential breakthroughs for the synchrotron radiation community (stable operation at high power for users, and high power coherent THz emission). The acquired understanding and the ultrafast acquisition techniques are of utmost interest to the entire accelerator physics community and beyond.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partners: Professor Dr. Serge Bielawski; Dr. Pascale Roy