Speaker
Mattias Marklund
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P5.2030.pdf
New routes to high-energy photon generation in laser-matter interactions
A. Gonoskov, T. Blackburn, M. Marklund
Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
Intense laser-plasma and laser-beam interactions are promising routes for producing high-
energy photons from compact setups, through, e.g. Compton scattering and bremsstrahlung
[1]. The small time and space scales associated with these emission mechanisms give such
sources unique properties. However, there are longstanding discussions as to the limit on the
achievable photon energies. Over the last decade, rigorous efforts in the development of particle-
in-cell (PIC) schemes with corrections from quantum electrodynamics (QED) have resulted
in many new and exciting predictions of high-energy photon generation. It has become clear
that many earlier concerns regarding the limitations of laser-plasma and laser-beam systems
as sources were unwarranted. Here, we will present results based on state-of-the-art QED-PIC
and analytical calculations on the generation of high-energy photons from laser-plasma [2]ăand
laser-beam systems [3].
Closely connected to the emission of high-energy photons areăelectromagnetic cascades of
electron-positron pairs. The latter have the potential to act as high-energy photon sources of
unprecedented brightness. In the cascade process, radiation reaction and rapid electron-positron
plasma production seemingly restrict the efficient production of photons to sub-GeV energies,
in line with the long-standing discussion mentioned above. Here, we show how the interplay
between the pair cascade and radiation reaction effects results in the possibility to emit GeV
photons. The possibility to use tailored laser fields as well as particular particle sources promises
not only the generation of high-energy photons, but also of controlled pair production at very
high densities. Such matter?anti-matter/radiation systems could be of importance for laboratory
astrophysics.
References
[1] F. Albert and A. G. R. Thomas, "Applications of laser wakefield accelerator-based light sources", Plasma
Phys. Control. Fusion 58, 103001 (2016)
[2] A. Gonoskov et al, "Ultrabright GeV Photon Source via Controlled Electromagnetic Cascades in Laser-
Dipole Waves", Phys. Rev. X 7, 041003 (2017)
[3] T. G. Blackburn, A. Ilderton, C. D. Murphy and M. Marklund, "Scaling laws for positron production in
laser–electron-beam collisions", Phys. Rev. A 96, 022128 (2017)
