Light Bending and Shadow of a Non-Singular Magnetically Charged Black Hole: Plasma Effects and EHT Constraints

The shadow and lensing of an asymptotic, magnetically charged, non-singular (AMCNS) black hole are profoundly modified in the presence of a plasma. We show that increasing plasma frequency enlarges the photon sphere radius, while the observed shadow radius decreases due to the dispersive plasma contribution. In contrast, the non-singularity parameter β decreases both the photon sphere and shadow radius. A comparison with the Event Horizon Telescope data for Sgr A* allows us to constrain the parameter space, favoring l∈(0,0.7) and specific low values of q. In weak-field lensing, we establish a definitive hierarchy of deflection angles: Uniform plasma causes the strongest bending, followed by vacuum and then a singular isothermal sphere (SIS) plasma. This lensing analysis predicts three images and demonstrates that plasma substantially boosts magnification. Our findings provide specific, testable predictions to identify regular black holes with magnetic charge against the complex backdrop of astrophysical plasmas.