相关论文: MHD jets around galactic objects

Magnetized accretion onto spinning black holes can accumulate a large magnetic flux across the event horizon and launch a pair of relativistic jets via the Blandford-Znajek mechanism. In the magnetically saturated (arrested) state, excess…

IPCVs contain a magnetic, rotating white dwarf surrounded by a magnetically truncated accretion disk. To explain their strong flickering X-ray emission, accretion has been successfully taken into account. Nevertheless, observations suggest…

Relativistic magnetized jets are key elements in Active Galactic Nuclei and in other astrophysical environments. Their structure and evolution involves a complex nonlinear physics that can be approached by numerical studies only. Still,…

Astrophysical jets, launched from the immediate vicinity of accreting black holes, carry away large amounts of power in a form of bulk kinetic energy of jet particles and electromagnetic flux. Here we consider a simple analytical model for…

Warped, precessing accretion discs appear in a range of astrophysical systems, for instance the X-ray binary Her X-1 and in the active nucleus of NGC4258. In a warped accretion disc there are horizontal pressure gradients that drive an…

We study the spherical accretion of magnetized plasma with low angular momentum onto a supermassive black hole, utilizing global general relativistic magnetohydrodynamic simulations. Black hole-driven feedback in the form of magnetic…

We present global hydrodynamic and magnetohydrodynamic (MHD) simulations with mesh refinement of accreting planets embedded in protoplanetary disks (PPDs). The magnetized disk includes Ohmic resistivity that depends on the overlying mass…

The nuclei of most normal galaxies contain supermassive black holes, which can accrete gas through a disk and become active. These Active Galactic Nuclei, AGN, can form jets which are observed on scales from AU to Mpc and from meter…

General relativistic numerical simulations of magnetized accretion flows around black holes show a disordered electromagnetic structure in the disk and corona and a highly relativistic, Poynting-dominated funnel jet in the polar regions.…

We want to test if self-similar magneto-hydrodynamic (MHD) accretion-ejection models can explain the observational results for accretion disk winds in BHBs. In our models, the density at the base of the outflow, from the accretion disk, is…

We show that accretion disks with magnetic fields in them ought to make jets provided that their electrical conductivity prevents slippage and there is an ambient pressure in their surroundings. We study equilibria of highly wound magnetic…

We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to study the effects of magnetic diffusivity on magnetically driven mass accretion and jet formation. We found that (1) when the normalized magnetic diffusivity, is…

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…

We compare two scenarios to launch jets -- formation by MHD processes or formation by thermal pressure in the boundary layer (BL) -- with respect to their compatibility with observational data of jets in symbiotic stars, especially in the…

The phenomenology of accretion disc, coronnae and jets in X-ray binaries is rather well established. However the structure of the accretion flow in the various spectral states is still debated and the connection between the hot flow and…

We consider a star as a compressible fluid subject to gravitational and magnetic forces. This leads to an Euler-Poisson system coupled to a magnetic field, which may be regarded as an MHD model together with gravity. The star executes…

Strong magnetic fields modify particle motion in the curved space-time of spinning black holes and change the stability conditions of circular orbits. We study conditions for magnetocentrifugal jet launching from accretion disks around…

We present a self-consistent MHD model for the jet of M87. The model consist of two distinct zones: an inner relativistic outflow, which we identify with the observed jet, and an outer cold disk-wind. While the former does not…

We present the results of a series of axisymmetric time-dependent magnetohydrodynamic (MHD) simulations of the propagation of cooling, overdense jets, motivated by the properties of outflows associated with young stellar objects. A variety…

We investigate the extraction of the rotational energy of a black hole under different accreting environment. When the accretion rate is moderate, the accretion disk consists of an outer thin disk and an inner advection-dominated accretion…