Related papers: A Magnetohydrodynamic Model for the Formation of E…
Black holes attract gaseous material from the surrounding environment. Cosmic plasma is largely ionized and magnetized because of electric currents flowing in the highly conductive environment near black holes; the process of accretion then…
We investigate the processes that lead to the formation, ejection and fall of a confined plasma ejection that was observed in a numerical experiment of the solar corona. By quantifying physical parameters such as mass, velocity, and…
We present our recent results from numerical simulations of a magnetized flow in the vicinity of a black hole in the context of the collapsar model for GRBs. The simulations show that after an initial transient, the flow settles into a…
A three-dimensional numerical experiment of the launching of a hot and fast coronal jet followed by several violent eruptions is analyzed in detail. These events are initiated through the emergence of a magnetic flux rope from the solar…
We have investigated magnetically driven superluminal jets originating from rotating black holes. The stationary, general relativistic, magnetohydrodynamic wind equation along collimating magnetic flux surfaces has been solved numerically.…
Accreting black holes produce powerful relativistic plasma jets which emit radiation across all observable wavelengths but the details of the initial acceleration and confinement of the jet are uncertain. We apply an innovative new model…
We present results from axisymmetric, time-dependent hydrodynamical (HD) and magnetohydrodynamical (MHD) simulations of a gaseous envelope collapsing onto a black hole (BH). We consider gas with so small angular momentum that after an…
Magnetic reconnection can power bright, rapid flares originating from the inner magnetosphere of accreting black holes. We conduct extremely high resolution ($5376\times2304\times2304$ cells) general-relativistic magnetohydrodynamics…
Collimated outflows (jets) are ubiquitous in the universe appearing around sources as diverse as protostars and extragalactic supermassive blackholes. Jets are thought to be magnetically collimated, and launched from a magnetized accretion…
The formation of jets in black hole accretion systems is a long-standing problem. It has been proposed that a jet can be formed by extracting the rotation energy of the black hole ("BZ-jet") or the accretion flow ("disk-jet"). While both…
It was suggested that the relativistic jets in gamma-ray bursts (GRBs) are powered via the Blandford-Znajek (BZ) mechanism or the annihilation of neutrinos and anti-neutrinos from a neutrino cooling-dominated accretion flow (NDAF). The…
We develop and discuss a model formalism to study the properties of mass outflows that are emerged out from a relativistic, magnetized, viscous, advective accretion flow around a rotating black hole. In doing so, we consider the toroidal…
We perform two-dimensional resistive magnetohydrodynamic simulations of coronal jets driven by flux emergence along the lower boundary. The reconnection layers are susceptible the formation of blobs that are ejected in the jet. Our…
Relativistic jets in active galactic nuclei, galactic microquasars, and gamma-ray bursts are widely considered to be magnetohydrodynamically driven by black hole accretion systems, although conversion mechanism from Poynting into particle…
Jets and outflows are thought to be an integral part of accretion phenomena and are associated with a large variety of objects. In these systems, the interaction of magnetic fields with an accretion disk and/or a magnetized central object…
We present results of recent observations and theoretical modeling of data from black holes accreting at very low luminosities (L/L_Edd ~ 10^{-8}). We discuss our newly developed time-dependent model for episodic ejection of relativistic…
Rotating magnetized compact objects and their accretion discs can generate strong toroidal magnetic fields driving highly magnetized plasmas into relativistic jets. Of significant concern, however, has been that a strong toroidal field in…
An introduction is given to a meeting on the role of massive and stellar black holes in powering non-thermal activity in a rich variety of cosmic sources. Relevant properties of magnetized, spinning black holes are summarized and their…
The X-ray and radio flares observed in X-ray binaries and active galactic nuclei (AGN) are attributed to energetic electrons in the plasma ejecta from the accretion flows near the black hole in these systems. It is argued that magnetic…
We present MHD simulations exploring the launching, acceleration and collimation of jets and disk winds. The evolution of the disk structure is consistently taken into account. Extending our earlier studies, we now consider the…