相关论文: Magnetic Penrose process in the magnetized Kerr sp…
In a paper posted on the arXiv a few weeks ago Berti, Brito and Cardoso \cite{Berti+14} suggest that ultra-high-energy particles can emerge from collisions in a black hole's ergosphere. This can happen if the process involves a particle on…
In this article, we explore the geodesics motion of neutral test particles and the process of energy extraction from a regular rotating Hayward black hole. We analyse the effect of spin, as well as deviation parameter $g$, on ergoregion,…
If supermassive black holes (SMBHs) are the energy sources that power quasars and active galactic nuclei, then QSO SDSS 1148+5251, the quasar with the highest redshift (z_QSO=6.43), hosts a supermassive black hole formed within 0.9 Gyr…
The collisional Penrose process received much attention when Banados, Silk and West (BSW) pointed out the possibility of test-particle collisions with arbitrarily high center-of-mass energy in the vicinity of the horizon of an extremally…
We consider generic axially symmetric rotating spacetimes and examine particle collisions in the ergoregion. The results are generic and agree with those obtained in the particular case of the rotating Teo wormhole in N. Tsukamoto and C.…
The possibility that rotating black holes could be natural particle accelerators has been subject of intense debate. While it appears that for extremal Kerr black holes arbitrarily high center of mass energies could be achieved, several…
We elucidate the `right' process for energy extraction from Kerr black holes through `FFDE' magnetospheres, free from causality violation. It is shown that the magnetosphere of a Kerr black hole possesses the double-structure, consisting of…
Acceleration of protons in the active galactic nuclei is considered. The largest energy is achieved by protons during centrifugal acceleration in the magnetosphere of the central machine. When the proton accelerated in the magnetosphere of…
Many efforts were made in order to better understand the energy extraction via magnetic reconnection from a rotating black hole, following the work of Comisso and Asenjo in 2021. We also tried to make some progress in our previous works, in…
In this study, the behavior of high-frequency quasi-periodic oscillations (QPOs) is investigated around a Kerr black hole immersed in a uniform Bertotti-Robinson magnetic field. The motion of the test particle is analyzed by determining the…
Recent observations of supermassive black holes have brought us new information on their magnetospheres. In this study we attempt a theoretical modelling of the coupling of black holes with their jets and discs, via three innovations.…
This paper examines regular black holes, in particular the Bardeen spacetime where singularities are replaced by non-singular cores. It explores the energy extraction through the charged Penrose process and shows that magnetic charge…
In this paper, we consider the analogy of the Penrose process in Charged Vaidya spacetime. We calculate the border of the generalized ergosphere, in which the charged particles with negative energy might exist, and show that it is…
I present a theoretical and numerical (Monte Carlo) N-particle analysis of Penrose scattering processes in the ergosphere of a supermassive Kerr black hole. These GR model calculations reveal that the observed high energies and luminosities…
The presence of a strong, large-scale magnetic field in an accretion flow leads to extraction of the rotational energy of the black hole (BH) through the Blandford-Znajek (BZ) process, believed to power relativistic jets in various…
We perform axisymmetric simulations of the magnetorotational collapse of very massive stars in full general relativity. Our simulations are applicable to the collapse of supermassive stars (M > 10^3M_sun) and to very massive Pop III stars.…
In association with the Blanford-Znajek mechanism for rotational energy extraction from Kerr black holes, it is of some interest to explore how much of magnetic flux can actually penetrate the horizon at least in idealized situations. For…
In this work we investigate the consequences of running gravitational coupling on the properties of rotating black holes. Apart from the changes induced in the space-time structure of such black holes, we also study the implications to…
In analogy with GRB 190114C, we here analyze the ultrarelativistic prompt emission (UPE) of GRB 180720B observed in the rest-frame time interval $t_{\rm rf}=4.84$--$10.89$~s by Fermi-GBM. We reveal the UPE hierarchical structure from the…
We investigate the steady, axisymmetric, force-free magnetosphere of Kerr-Sen black hole (BH) within the framework of the Einstein-Maxwell-dilaton-axion (EMDA) theory. By perturbatively solving the nonlinear Grad-Shafranov (GS) equation, we…