Sensitivity of the COHERENT Experiment to Accelerator-Produced Dark Matter

TL;DR

The paper evaluates how the COHERENT experiment's low-energy recoil detectors can effectively constrain sub-GeV dark matter models, especially using timing and detector design, to explore new physics beyond the standard model.

Contribution

It demonstrates the potential of a 750-kg liquid argon detector at COHERENT to set leading limits on scalar light dark matter models over a wide mass range, utilizing timing structure for background reduction.

Findings

The detector can constrain dark matter models over two orders of magnitude in mass.

Timing information improves background discrimination and sensitivity.

Future enhancements could further increase discovery potential.

Abstract

The COHERENT experiment is well poised to test sub-GeV dark matter models using low-energy recoil detectors sensitive to coherent elastic neutrino-nucleus scattering (CEvNS) in the $\pi$-DAR neutrino beam produced by the Spallation Neutron Source. We show how a planned 750-kg liquid argon scintillation detector would place leading limits on scalar light dark matter models, over two orders of magnitude of dark matter mass, for dark matter particles produced through vector and leptophobic portals in the absence of other effects beyond the standard model. The characteristic timing structure of a $\pi$-DAR beam allows a unique opportunity for constraining systematic uncertainties on the standard model background in a time window where signal is not expected, enhancing expected sensitivity. Additionally, we discuss future prospects, further increasing the discovery potential of CEvNS detectors. Such methods would test the calculated thermal dark matter abundance for all couplings $\alpha'\leq1$ within the vector portal model over an order of magnitude of dark matter masses.