Related papers: Vacuum breakdown in a misaligned magnetized Kerr s…
With mass ratio larger than $\sim 5$ (which depends on the black hole spin and the star radius), star disruption is not expected for a black hole merging with a neutron star during the final plunge phase. In the late inspiral stage, the…
We study the effects of pair creation on the radiation emerging from black holes under the assumption that the magnetic fields are vortex driven. In particular, for a sufficiently broad range of supermassive black holes, we investigated the…
Recently it has been found that the superposition of a strong and slow electric field with a weaker and faster pulse can significantly enhance the probability for non-perturbative electron-positron pair creation out of the vacuum -- the…
The process of electron-positron pair production by two photons in a strong magnetic field has been studied. The process kinematics is considered, and the probability amplitude for arbitrary polarizations of particles is found. The…
Experiments at HERA looking for deep-inelastic electroproduction of neutrons in the proton fragmentation region are in progress. They are aimed to measure the pion structure function at small Bjorken $x$. The important condition for such a…
The disk of an active galactic nucleus (AGN) is widely regarded as a prominent formation channel of binary black hole (BBH) mergers that can be detected through gravitational waves (GWs). Besides, the presence of dense environmental gas…
Most black holes (BHs) will absorb a neutron star (NS) companion fully intact, without tidal disruption, suggesting the pair will remain dark to telescopes. Even without tidal disruption, electromagnetic luminosity is generated from the…
The transformation of electromagnetic energy into matter represents a fascinating prediction of relativistic quantum electrodynamics that is paradigmatically exemplified by the creation of electron-positron pairs out of light. However, this…
We consider the vacuum decay by electron-positron pair production in spatially homogeneous, time dependent electric fields by means of quantum kinetic equations. Our focus is on the impact of various pulse shapes as envelopes of oscillating…
In a strong magnetic field, B > 4x10^{12} G, gamma-rays emitted nearly along curved field lines adiabatically convert into bound electron-positron pairs (positronium atoms) rather that decaying into free pairs. This process may modify the…
The idea that the vacuum polarization process occurring during gravitational collapse to a black hole endowed with electromagnetic structure (EMBH) could be the origin of gamma ray bursts (GRBs) is further developed. EMBHs in the range 3.2…
We study the orbital structure and precession dynamics of neutral test particles in the magnetized Kerr black hole (MKBH) spacetime-an exact electrovacuum solution of the Einstein-Maxwell equations that self-consistently incorporates the…
We analyze the extraction of the rotational energy of a Kerr black hole (BH) endowed with a test charge and surrounded by an external test magnetic field and ionized low-density matter. For a magnetic field parallel to the BH spin,…
The highly luminous and variable prompt emission in Gamma-Ray Bursts (GRBs) arises in an ultra-relativistic outflow. The exact underlying radiative mechanism shaping its non-thermal spectrum is still uncertain, making it hard to determine…
Production of electron-positron pairs from the quantum vacuum polarized by the superposition of a strong and a perturbative oscillating electric-field mode is studied. Our outcomes rely on a nonequilibrium quantum field theoretical…
The process of pair creation by a photon in a strong magnetic field is investigated basing on the polarization operator in the field. The total probability of the process is found in a relatively simple form. The probability exhibits a…
Tidal torques from a binary black hole (BHBH) empty out the central regions in any circumbinary gaseous accretion disk. The balance between tidal torques and viscosity maintain the inner edge of the disk at a radius r ~ 1.5a -- 2a, where a…
We perform force-free simulations for a neutron star orbiting a black hole, aiming at clarifying the main magnetosphere properties of such binaries towards their innermost stable circular orbits. Several configurations are explored, varying…
[Abridged] Electromagnetic emission can be produced as a precursor to the merger, as a prompt emission during the collapse of a NS and at the spin-down stage of the resulting BH. We demonstrate that the time evolution of the axisymmetric…
Electron-positron pair production by means of vacuum polarization in the presence of strong electromagnetic (EM) field of two counterpropagating laser pulses is studied. A 3-dimensional model of the focused laser pulses based on the…