Layout optimization for the LUXE-NPOD experiment

Beam dump experiments represent an effective way to probe new physics in a parameter space, where new particles have feeble couplings to the Standard Model sector and masses below the GeV scale. The LUXE experiment, designed primarily to study strong-field quantum electrodynamics, can be used also as a photon beam dump experiment with a unique reach for new spin-0 particles in the 10–350 MeV mass and 10$^{−6}$–10$^{−3}$  GeV$^{−1}$ couplings to photons ranges. This is achieved via the “new physics search with optical dump” (NPOD) concept. While prior estimations were obtained with a simplified model of the experimental setup, in this work we present a systematic study of the new physics reach in the full, realistic experimental apparatus, including an existing detector to be used in the LUXE NPOD context. We furthermore investigate updated scenarios of LUXE’s experimental plan and confirm that our results are in agreement with the original estimations of a background-free operation.