# Dark matter signals from timing spectra at neutrino experiments

## TL;DR

This paper introduces a new timing-based method to detect dark matter signals at neutrino experiments, demonstrating its potential with the COHERENT data and exploring future sensitivities.

## Contribution

It proposes a novel resonance-like timing signature for dark matter detection and applies it to existing data, providing new insights and future experimental prospects.

## Key findings

- Detected an excess in timing distribution consistent with dark matter hypothesis
- Demonstrated the method's ability to distinguish signal from background
- Compared sensitivity of current and future experiments for dark matter detection

## Abstract

We propose a novel strategy to search for new physics in timing spectra, envisioning the situation in which a new particle comes from the decay of its heavier partner with a finite particle width. The timing distribution of events induced by the dark matter particle scattering at the detector may populate in a relatively narrow range, forming a "resonance-like" shape. Due to this structural feature, the signal may be isolated from the backgrounds, in particular when the backgrounds are uniformly distributed in energy and time. For proof of the principle, we investigate the discovery potential for dark matter from the decay of a dark photon in the COHERENT experiment, and show the exciting prospects for exploring the associated parameter space with this experiment. We analyze the existing CsI detector data with a timing cut and an energy cut, and find, for the first time, an excess in the timing distribution which can be explained by such dark matter. We compare the sensitivity to the kinetic mixing parameter ($\epsilon$) for current and future COHERENT experiments with the projected limits from LDMX and DUNE.