Delayed Signals in Liquid Xenon Particle Detectors

Dual-phase xenon time projection chambers are a leading technology sensitive to a wide range of dark matter particle masses. At interaction energies relevant to searches for axion-like particles and light weakly interacting particles, these detectors (including XENON1T and LUX) have identified delayed signals correlated with high-energy interactions. Elevated rates of electrons and photons decay with power laws that dominate detector activity up to a second after the initial interaction. In this talk, I will summarize the phenomenology of these backgrounds, and present new results on delayed signals in a radial single-phase liquid xenon proportional scintillation counter.