Conceptual Design Report for the LUXE Experiment

TL;DR

The LUXE experiment aims to explore high-energy quantum electrodynamics by combining the European XFEL electron beam with a powerful laser, probing extreme field strengths and searching for new physics beyond the Standard Model.

Contribution

This report presents the conceptual design of LUXE, integrating high-energy electron beams with intense lasers to investigate uncharted quantum regimes and potential new physics.

Findings

Probing effective field strengths at and beyond the Schwinger limit

Achieving high-precision measurements for detailed theory comparison

Predicting high photon flux for new physics searches

Abstract

This Conceptual Design Report describes LUXE (Laser Und XFEL Experiment), an experimental campaign that aims to combine the high-quality and high-energy electron beam of the European XFEL with a powerful laser to explore the uncharted terrain of quantum electrodynamics characterised by both high energy and high intensity. We will reach this hitherto inaccessible regime of quantum physics by analysing high-energy electron-photon and photon-photon interactions in the extreme environment provided by an intense laser focus. The physics background and its relevance are presented in the science case which in turn leads to, and justifies, the ensuing plan for all aspects of the experiment: Our choice of experimental parameters allows (i) effective field strengths to be probed at and beyond the Schwinger limit and (ii) a precision to be achieved that permits a detailed comparison of the measured data with calculations. In addition, the high photon flux predicted will enable a sensitive search for new physics beyond the Standard Model. The initial phase of the experiment will employ an existing 40 TW laser, whereas the second phase will utilise an upgraded laser power of 350 TW. All expectations regarding the performance of the experimental set-up as well as the expected physics results are based on detailed numerical simulations throughout.