Optical appearance of a thin-shell wormhole with a Hayward profile

Abstract: The optical properties of a thin-shell wormhole (TSW) with a Hayward profile is investigated. Adopting the ray-tracing method, we demonstrate that the TSW's contralateral spacetime is capable of reflecting a significant portion of light back to the observer spacetime. We analyze the effective potential, light deflection, and azimuthal angle of the TSW and find that these quantities are affected by the mass ratio of the black holes (BHs). Specifically, if the mass of the contralateral spacetime BH is greater than that of the original spacetime BH, and the impact parameter satisfies the condition $Hb_{\rm c2}<b_{1}<b_{\rm c1}$, the trajectory of the photon exhibits round-trip characteristics. Assuming the presence of a thin accretion disk surrounding the observing spacetime BH, our results indicate that the image formed by the TSW exhibits additional photon rings and a lensing band compared to an image produced by a BH alone.