Plasma and conventional undulator studies using ultra-short electron bunches- towards a bright ultra-short pulsed X-ray source
Abstract
We propose to investigate the use of a laser-plasma accelerator (LPA) to produce incoherent and coherent radiation from undulators, with a focus on plasma undulators, and using both experimental and theoretical methods. We will study the emission of coherent radiation from femtosecond to attosecond electron bunches as they traverse a short conventional undulator with a periodicity of 4 cm. We will also explore the emission of coherent undulator transition radiation (or coherent edge radiation) as the electrons change their average velocity when they enter and exit the undulator, and study methods of inertial bunch compression of energy-chirped electrons from the LPA to reach fewattosecond electron bunches. We will then investigate similar phenomena in a plasma undulator where the electrostatic forces inside the laser wakefield bubble will be used to drive transverse oscillations of accelerating electrons with a undulator wavelength of several 100 microns. The high amplitude or wiggler regime (K>>1) will be investigated, with particular attention to investigating harmonic emission and the transfer of coherence to higher harmonics. We will also investigate the feasibility of an ion-channel free-electron laser (FEL) based on a plasma undulator. In addition, we will extend the studies to investigate similar phenomena using these plasmon enhanced field-emission based undulators being fabricated under another AFOSR Grant. These plasma-based and plasmon field-enhanced undulators have potential to significantly miniaturise synchrotrons and FELs to make them more widely available as femtosecond to attosecond XUV to X-ray probes, which will find many applications. The advantage of plasma based undulators is they have the potential to generate 0.5 to 3 femtosecond pulse widths with coherent, high yield x-rays (10^14 photons). The advantage of plasmonic undulators is that they can generate long (duration of the laser pulse), high yield X-ray pulses with high energies (> MeV) and high pulse rates due to lower power laser pulse requirements and lack of plasma disruption. We will utilise 40 TW and 350 TW Ti-sapphire lasers at the University of Strathclyde for the experimental studies, and particle-in-cell simulations to design experiments and interpret experimental data.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2023
- Source ID
- FA86552217004
Entities
People
- D. A. Jaroszynski
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Strathclyde