Merger estimates for rotating Kerr black holes in modified gravity

Understand

In this paper, we explore the signatures of non-rotating and rotating black hole mergers in the matter-free modified gravity.

• First, we solve the unstable circular null orbits and the innermost stable circular timelike orbits via the geodesic motion.
• The characteristic quantities of these orbits are systematically analyzed by varying the black hole spin and the scalar field parameter of the gravity.
• Then based on it, we study the ringdown modes from the light ring/quasinormal modes correspondence.