Critical Mass: Collective radiation-beam-plasma interactions at high intensities

This proposal describes a programme of research on single-particle and collective radiation-beam-plasma interactions at high field intensities, production of high-brightness particle beams with femtosecond to attosecond duration, new sources of coherent and incoherent radiation that are both compact and inexpensive, new methods of accelerating particles which could make them widely available and, by extending their parameter range, stimulate new application areas. An important adjunct to the proposal will be a programme to apply the sources to demonstrate their usefulness and also provide a way to involve industry and other end-users. The project builds on previous experiments and theoretical investigations of the Advanced Laser Plasma High-energy Accelerators towards X-rays (ALPHA-X) project, which has demonstrated controlled acceleration in a laser-plasma wakefield accelerator (LWFA), initial applications of beams from the LWFA and demonstrations of gamma ray production due to resonant betatron motion in the LWFA. The programme will have broad relevance, through developing an understanding of the highly nonlinear and collective physics of radiation-matter interactions, to fields ranging from astrophysics, fusion and nuclear physics, to the interaction of radiation with biological matter. It will also touch on several basic problems in physics, such as radiation reaction in plasma media and the development of coherence in nonlinear coupled systems.

"Developed a compact, ultra-bright, attosecond duration coherent XUV radiation source, based on the laser-plasma wakefield accelerator (LWFA).

Developed a kiloAmpere femtosecond-duration, high-current relativistic electron beam source from a LWFA.

Demonstrated the LWFA as a high resolution source for phase-contrast medical X-ray imaging.

Developed plasma density tapering in LWFA accelerators as a means to boost output properties such as higher electron energy or shorter bunch duration.

Investigated high energy electron beam radiotherapy and carried out dosimetry and radiobiology studies to measure cell survival of cancer cells up to 10 Gray doses.

Developed a bright femtosecond gamma-ray source based on the laser wakefield accelerator.

Developed a high charge, 30 nanoCoulomb, 2 MeV electron beam source based on laser-plasma interactions in under-dense plasma.

Measured and fully characterised all the relevant beam properties of high energy electron beams from a LWFA.

Developed the basic theory of the ion channel laser for use with the LWFA.

Undertook measurements of XUV undulator measurements to demonstrate a compact synchrotron source based on the LWFA.

Measured eight orders of magnitude gain in a 2 mm long plasma Raman amplifier.

Developed a new Kinetic theory of radiation reaction.

Developed a fundamentally new formulation of radiation reaction of electrons in ultra-intense laser fields based on higher order Maxwell electrodynamics.

Developed a new simulation tool for Laser-Plasma interactions using spatially compact finite energy laser pulses.

Investigated the implications of Stern-Gerlach-type forces in laser wakefield accelerators.

Demonstrated radio-isotope production using a LWFA using a compact LWFA-based gamma ray source, which could be suitable for producing radio-isotopes for nuclear medicine and imaging applications."