Polarized image of a Schwarzschild black hole with a thin accretion disk as photon couples to Weyl tensorZelin Zhang, Songbai Chen, Xin Qin and Jiliang JingEur. Phys. J. C, 81 11 (2021) 991DOI: https://doi.org/10.1140/epjc/s10052-021-09786-2