Quasinormal Modes of Non-Linearly Charged Black Holes surrounded by a Cloud of Strings in Rastall Gravity

Understand

We obtain the black hole solution for the Ay\'on - Beato - Garc\'ia (ABG) type black hole surrounded by a cloud of strings in Rastall gravity and calculate the scalar quasinormal modes of it for a massless scalar field.

• To have a better visualization of the results, we also introduce a new non-linear electrodynamic source and obtain a black hole solution surrounded by a cloud of strings in the Rastall gravity.
• We see that the quasinormal modes are affected by the type of non-linear electrodynamic sources in case of higher magnitudes of charge $q$.
• With increase in the magnitude of charge $q$, gravitational waves decay rapidly for the new black hole solution, while for the ABG black hole, the decay rate increases initially and finally starts to decrease near to $q=1$.