Abstract
We consider the scattering of probe particles on an ultra-boosted beam of charge, in the case that the fields of the beam are strong and must be treated non-perturbatively. We show that the fields of the ultra-boosted beam act as stochastic plane waves - scattering amplitudes (of elastic scattering, nonlinear Compton and nonlinear Breit-Wheeler) are obtained without approximation by averaging plane wave scattering amplitudes over all possible plane wave parameters. The relevant plane waves are ultra-short and, as such, scattering on ultra-boosted beams does not exhibit the conjectured strong-field behaviour of QED based on the locally constant field approximation.
Highlights
A strong background field is characterized by a coupling to charged particles which is larger than unity
We show that the fields of the ultraboosted beam act as stochastic plane waves—scattering amplitudes are obtained without approximation by averaging plane wave scattering amplitudes over all possible plane wave parameters
IV we make a connection with laser-particle scattering; we show that, despite the very different physical situations, the exact solutions of the Dirac equation can be written without approximation in terms of the Volkov solutions of the Dirac equation in a background plane wave [19]
Summary
A strong background field is characterized by a coupling to charged particles which is larger than unity. While studies of laser-particle collisions have traditionally followed this approach (usually modeling the laser fields as plane waves) strong field QED in beam-beam interactions has been studied numerically using particle-in-cell simulations and models based on the (locally) constant field approximation [7,8]. If the physical situation of interest is the collision of heavily boosted beams, particles or ions, the fields of one bunch as seen by the other will be very strongly Lorentz contracted and switch rapidly on and off It is natural (not least given the well-studied shortcomings of the locally constant field approximation [15,16,17,18]) to investigate other methods for studying strong-field effects in beam-beam collisions.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
