Charged particle and epicyclic motions around $4D$ Einstein-Gauss-Bonnet black hole immersed in an external magnetic field

Abstract

We investigate particle motion in the vicinity of a 4D Einstein-Gauss-Bonnet (EGB) black hole immersed in external asymptotically uniform magnetic field.It is well known that magnetic fields can strongly affect charged particle motion in the black hole vicinity due to the Lorenz force. We find that the presence of the Gauss-Bonnet (GB) coupling gives rise to a similar effect, reducing the radius of the innermost stable circular orbit (ISCO) with respect to the purely relativistic Schwarzschild black hole. Further, we consider particle collisions in the black hole vicinity to determine the center of mass energy and show that this energy increases with respect to the Schwarzschild case due to the effect of the GB term. Finally, we consider epicyclic motion and its frequencies and resonance as a mean to test the predictions of the model against astrophysical observations. In particular we test which values of the parameters of the theory best fit the 3:2 resonance of high-frequency quasi-periodic oscillations in three

Shadow, deflection angle and quasinormal modes of Born-Infeld charged black holes

“…In [13], the consistent Aoki-Gorji-Mukohyama theory of 4D EGB gravity was proposed and several applications were further studied in [14,15]. In fact, the novel 4D EGB theory of gravity has recently attracted much attention in a wide context of black hole physics [16][17][18][19][20][21], and applications, such as, in black hole shadows [22][23][24][25], thermodynamics issues [26,27], rotating solutions [28][29][30], stability issues [31][32][33][34][35][36][37][38], gravitational lensing [39], thin accretion disk around 4D EGB black holes [40], causal structure [41,42], and black hole solutions coupled to nonlinear electrodynamics (NLED) [43,[43][44][45][46][47].…”

Constraints on the magnetized Ernst black hole spacetime through quasiperiodic oscillations

“…Note that the dot in the above equation denotes the derivative with respect to the proper time. These frequencies are measured by a local observer and defined by the following equations [55,69]…”

“…Let us then define ν as a frequency measured by a distant observer located at infinity. It is worth noting that the frequencies measured by local and distant observers are related by the following transformation [55,69]…”

“…However, there exists no reasonable model that can explain the appearance of such HF QPOs [52]. For that reason, the epicyclic motion of charged particles around a black hole surrounded by a magnetic field has been proposed to explain such phenomena [53][54][55]. Also, twin peak HF QPOs that usually arise in pairs (i.e.…”

Shadow, deflection angle and quasinormal modes of Born-Infeld charged black holes

“…It is worthwhile to mention that these theories still hold the spherically symmetric 4D black holes as valid solutions [10,11]. In fact, the novel 4D EGB theory of gravity has recently attracted much attention in a wide context of black hole physics [13][14][15][16][17][18], and applications, such as, in black hole shadows [19][20][21][22], thermodynamics issues [23,24], rotating solutions [25][26][27], stability issues [28][29][30][31][32][33][34][35], gravitational lensing [36], thin accretion disk around 4D EGB black holes [37], causal structure [38,39], and black hole solutions coupled to nonlinear electrodynamics [40][41][42][43][44].…”