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arXiv · 2406.10342

Fundamental constants from photon-photon scattering in three-beam collisions

Alexander J. Macleod·Ben King
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Abstract

Direct measurement of the elastic scattering of real photons on an electromagnetic field would allow the fundamental low-energy constants of quantum electrodynamics (QED) to be experimentally determined. We show that scenarios involving the collision of three laser beams have several advantages over conventional two-beam scenarios. The kinematics of a three-beam collision allows for a higher signal-to-noise ratio in the detection region, without the need for polarimetry and separates out contributions from different orders of photon scattering. A planar configuration of colliding a photon beam from an x-ray free electron laser with two optical beams is studied in detail. We show that measurements of elastic photon scattering and vacuum birefringence are possible with currently available technology.

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Alexander J. Macleod, Ben King. 2024-06-14. Fundamental constants from photon-photon scattering in three-beam collisions. https://doi.org/10.1103/physreva.110.032216

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