Polarized image of an equatorial emitting ring around a Konoplya-Zhidenko rotating non-Kerr black hole*

Abstract We investigate the polarized images of an equatorial emitting ring around a rotating Konoplya-Zhidenko non-Kerr black hole, which incorporates an additional deformation parameter. This deformation parameter, η , permits the spin parameter to exceed the upper bound imposed by the standard Kerr black hole. Our results indicate that the polarized images depend not only on the magnetic field configuration, fluid velocity, and observer inclination angle, but also on the spin and deformation parameters. As the deformation parameter increases, the polarization intensity decreases monotonically. Conversely, the magnitude of the Electric Vector Position Angle (EVPA) increases with η . Furthermore, we observe that η may induce subtle yet discernible azimuthal separation features, potentially distinguishing its effects from those of the spin parameter and the magnetic field orientation angle. Nevertheless, these features remain difficult to resolve under current observational conditions and will require verification by future high-resolution facilities such as the next-generation Event Horizon Telescope (ngEHT).