English

Self-Focussing of an Intense X-Ray Beam in Vacuum

Optics 2021-07-08 v2 High Energy Physics - Phenomenology

Abstract

The quantum vacuum shows an intensity-dependent nonlinear index of refraction. Consequently, we may consider vacuum as a non-linear medium enabling, at sufficiently high field strengths, a direct interaction of light with light. In this context, we advocate an experiment to measure light-by-light scattering by the means of self-focussing of an x-ray beam in vacuum. Although hard to measure, we argue that for laser beams consisting of highly energetic photons the beams' power distribution carries a distinctive enough signature of self-focussing such that an observation at modern free-electron laser facilities appears possible. Self-focussing also imposes a limit on the most powerful x-ray beams that may propagate in vacuum being on the order of 1010 PW for 1010 keV x-rays.

Keywords

Cite

@article{arxiv.2105.08006,
  title  = {Self-Focussing of an Intense X-Ray Beam in Vacuum},
  author = {Roland Sauerbrey and Christian Kohlfürst},
  journal= {arXiv preprint arXiv:2105.08006},
  year   = {2021}
}

Comments

There has been an error in the manuscript, in Sec. I. We have decided to withdraw the article temporarily, while we are working on an update