Dark photons (DPs) produced in the early Universe are well-motivated dark matter (DM) candidates. We show that the recently proposed tunable plasma haloscopes are particularly advantageous for DP searches. While in-medium effects suppress the DP signal in conventional searches, plasma haloscopes make use of metamaterials that enable resonant absorption of the DP by matching its mass to a tunable plasma frequency and thus enable efficient plasmon production. Using thermal field theory, we confirm the in-medium DP absorption rate within the detector. This scheme allows to competitively explore a significant part of the DP DM parameter space in the DP mass range of 6−400μeV. If a signal is observed, the observation of a daily or annual modulation of the signal would be crucial to clearly identify the signal as due to DP DM and could shed light on the production mechanism.
@article{arxiv.2006.06836,
title = {Probing dark photons with plasma haloscopes},
author = {Graciela B. Gelmini and Alexander J. Millar and Volodymyr Takhistov and Edoardo Vitagliano},
journal= {arXiv preprint arXiv:2006.06836},
year = {2020}
}
Comments
13 pages, 4 figures. Added several references, a new figure and minor changes to match published version