Observational appearance and extra photon rings of an asymmetric thin-shell wormhole with a Bardeen profile* *Supported by the National Natural Science Foundation of China (11903025), the Science and Technology Program of Sichuan Province, China(2023ZYD0023), and the starting fund of China West Normal University (18Q062)

Abstract

In this work, the optical appearance of an asymmetric thin-shell wormhole with a Bardeen profile is studied. To initiate the process, we need to construct an asymmetric thin-shell wormhole utilizing the cut-and-paste technique proposed by Visser and subsequently ascertain its pertinent physical quantities such as the radius of the photon sphere and critical impact parameters for different values of magnetic charge g. Then, the effective potential and motion behavior of photons are also investigated within the framework of asymmetric thin-shell wormholes with a Bardeen profile. It can be found that the effective potential, ray trajectory, and azimuthal angle of the thin-shell wormhole exhibit a strong correlation with the mass ratio of black holes. By considering the accretion disk as the sole background light source, we observe additional photon rings and lensing bands in the optical appearance of the asymmetric thin-shell wormhole with a Bardeen profile compared to those exhibited by the Bardeen black hole. One can find that there is an increase in the size of the specific additional light bands with increasing magnetic charge g, which is different from the black hole case. These exceptionally luminous rings can serve as a robust criterion for the identification and characterization of the thin-shell wormhole spacetime.