Periodic Orbits and Gravitational Wave Radiation of Black Holes in 4D-EGB gravity
Periodic Orbits and Gravitational Wave Radiation of Black Holes in 4D-EGB gravity
Liping Meng, Zhaoyi Xu, Meirong Tang
AbstractIn the paper, we study the dynamical behavior of a particle around a charged black hole within the framework of 4D-EGB gravity theory. Based on the spacetime metric of the black hole, we rigorously derived the effective potential of the particle and analyzed the particle's MBO and ISCO. The results show that the key physical quantities of MBO and ISCO-including orbital radius, angular momentum, and energy-all exhibit significant dependence on parameter $\alpha$ and charge $Q$. As these two parameters increase, the energy-angular momentum ($E, L$) region required for particle bound orbits shifts towards lower ($E, L$) areas. Furthermore, in order to assess the validity of the chosen values for parameter $\alpha$ and charge $Q$, a rigorous constraint on these parameters is imposed in this paper, utilizing observational data from the black hole shadows of $M87^{\ast }$ and $Sgr A^{\ast }$ and precession observations of the $S2$ star. Finally, we analyzed the periodic orbits of particle and their generated gravitational waveforms under different parameter values. We found that changes in parameter $\alpha$ and charge $Q$ lead to significant differences in the periodic trajectories of the particle and their corresponding gravitational waveforms.