Passive Ballistic Microbunching of Non-Ultrarelativistic Electron Bunches using Electromagnetic Wakefields in Dielectric-Lined Waveguides

Abstract

Temporally-modulated electron beams have a wide array of applications ranging from the generation of coherently-enhanced electromagnetic radiation to the resonant excitation of electromagnetic wakefields in advanced-accelerator concepts. Likewise producing low-energy ultrashort microbunches could be useful for ultra-fast electron diffraction and new accelerator-based light-source concepts. In this Letter we propose and experimentally demonstrate a passive microbunching technique capable of forming a picosecond bunch train at $\sim 6$~MeV. The method relies on the excitation of electromagnetic wakefields as the beam propagates through a dielectric-lined waveguide. Owing to the non-ultrarelativistic nature of the beam, the induced energy modulation eventually converts into a density modulation as the beam travels in a following free-space drift. The modulated beam is further accelerated to $\sim 20$~MeV while preserving the imparted density modulation.

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Cited by in corpus (8)

• Enhanced versatility of table-top X-rays from van der Waals structures
• Bunch Shaping in Electron Linear Accelerators
• Longitudinal phase space synthesis with tailored 3D-printable dielectric-lined waveguides
• Drive beam sources and longitudinal shaping techniques
• Travelling Wakefield Tube: THz Source Powered by Nonrelativistic Electron Beam
• Coupled bunch stability with variable filling patterns in PETRA IV
• Microbunching Instability Characterisation via Temporally Modulated Laser Pulses
• Adaptive Latent Space Tuning for Non-Stationary Distributions