Axion-like Particles at Future Neutrino Experiments: Closing the "Cosmological Triangle"

TL;DR

Future neutrino experiments like DUNE can effectively search for axion-like particles by detecting their interactions with photons, covering new parameter space and potentially exploring the entire 'cosmological triangle' region.

Contribution

This paper demonstrates that DUNE-like detectors can probe a wide range of ALP-photon couplings and masses, including regions previously unconstrained, thus advancing ALP search capabilities.

Findings

DUNE-like detectors can explore ALP masses up to 3-4 GeV.

Sensitivity to ALP-photon coupling down to 10^{-8} GeV^{-1}.

Full coverage of the 'cosmological triangle' region.

Abstract

Axion-like particles (ALPs) provide a promising direction in the search for new physics, while a wide range of models incorporate ALPs. We point out that future neutrino experiments, such as DUNE, possess competitive sensitivity to ALP signals. The high-intensity proton beam impinging on a target can not only produce copious amounts of neutrinos, but also cascade photons that are created from charged particle showers stopping in the target. Therefore, ALPs interacting with photons can be produced (often energetically) with high intensity via the Primakoff effect and then leave their signatures at the near detector through the inverse Primakoff scattering or decays to a photon pair. Moreover, the high-capability near detectors allow for discrimination between ALP signals and potential backgrounds, improving the signal sensitivity further. We demonstrate that a DUNE-like detector can explore a wide range of parameter space in ALP-photon coupling $g_{a\gamma}$ vs ALP mass $m_a$, including some regions unconstrained by existing bounds; the "cosmological triangle" will be fully explored and the sensitivity limits would reach up to $m_a\sim3-4$ GeV and down to $g_{a\gamma}\sim 10^{-8} {\rm GeV}^{-1}$.