Hunting Axion Dark Matter with Protoplanetary Disk Polarimetry

Abstract

We find that the polarimetric observations of protoplanetary disks are useful to search for ultra-light axion dark matter. Axion dark matter predicts the rotation of the linear polarization plane of propagating light, and protoplanetary disks are ideal targets to observe it. We show that a recent observation puts the tightest constraint on the axion-photon coupling constant for axion mass $m\lesssim 10^{-21}$eV.

Comments: 5 pages, 3 figures, Updated to match the version accepted by PRL