相关论文: Relativistic Jets from Collapsars

An ejection mechanism of relativistic jets from slim disks is studied. Since the radiation pressure is dominant in the slim disk, radiative energy flow arises along the pressure gradient in the vertical direction. The divergence of the…

The prompt emission of gamma-ray bursts (GRBs) is characterized by rapid variabilities, which may be a direct reflection of the unsteady central engine. We perform a series of axisymmetric 2.5-dimensional simulations to study the…

Jets are found in a variety of astrophysical sources, from young stellar objects to active galactic nuclei. In all the cases the jet propagates with a supersonic velocity through the external medium, which can be inhomogeneous, and…

We provide estimates for the flux and maximum frequency of radiation produced when the magnetic field in a relativistic, highly magnetized, jet is dissipated and particles are accelerated using general considerations. We also provide limits…

We consider a model for the low-luminosity gamma-ray burst GRB 060218 that plausibly accounts for multiwavelength observations to day 20. The model components are: (1) a long-lived ($t_j \sim 3000$ s) central engine and accompanying…

Short gamma-ray bursts (GRBs) are believed to be produced by relativistic jets from mergers of neutron-stars (NS) or neutron-stars and black-holes (BH). If the Lorentz-factors $\Gamma$ of jets from compact-stellar-mergers follow a similar…

We examine and develop the model of gamma ray bursts origin proposed by Shaviv and Dar (astro-ph/9606032), according to which the strong gamma ray emission is produced by the interaction of the baryonic relativistic jet (outflow) with the…

Blazars are thought to possess a relativistic jet that is pointing toward the direction of the Earth and the elect of relativistic beaming enhances its apparent brightness. They radiate in all wavebands from the radio to the gamma-ray bands…

Jet formation is connected most probably with matter acceleration from the vicinity of rotating magnetized bodies. It is usually related to the mass outflows and ejection from accretion disks around black holes. Problem of jet collimation…

The 'event' that triggers a gamma ray burst cannot last for more than a few seconds. This is, however, long compared with the dynamical timescale of a compact stellar-mass object ($\sim 10^{-3}$ seconds). Energy is assumed to be released as…

We have carried out 2D and 3D general relativistic magnetohydrodynamic simulations of jets launched self-consistently from accretion disks orbiting Kerr black holes and applied the results to the inner engine of the collapsar model of…

Apparent evolution of relativistic flows as traced by radio emission results from a combination of several factors related to propagation of relativistic blobs or shocks, velocity, density and pressure stratification of the underlying flow,…

The association of at least some long gamma-ray bursts with type Ic supernova explosions has been established beyond reasonable doubt. Theoretically, the challenge is to explain the presence of a light hyper-relativistic flow propagating…

Based on recent models of relativistic jet formation by thermal energy deposition around black hole-torus systems, the relation between the on- and off-axis appearance of short, hard gamma-ray bursts (GRBs) is discussed in terms of…

The deaths of massive stars are sometimes accompanied by the launch of highly relativistic and collimated jets. If the jet is pointed towards Earth, we observe a "prompt" gamma-ray burst due to internal shocks or magnetic reconnection…

After many years of speculation, recent observations have confirmed the association of gamma-ray bursts with core-collapse supernova explosions from massive stars. This association carries with it important consequences. The burst…

We estimate the power of relativistic, extragalactic jets by modelling the spectral energy distribution of a large number of blazars. We adopt a simple one-zone, homogeneous, leptonic synchrotron and inverse Compton model, taking into…

Outflows/jets are ubiquitous in a wide range of astrophysical objects, yet the mechanisms responsible for their generation remain elusive. One hypothesis is that they are magnetically driven. Based on general relativistic MHD equations, we…

Relativistic jets accompany the collapse of massive stars, the merger of compact objects, or the accretion of gas in active galactic nuclei. They carry information about the central engine and generate electromagnetic radiation. No…

In certain general relativistic time-dependent gravitational fields, free test particles can asymptotically line up relative to fiducial static observers and produce a cosmic jet whose speed approaches the speed of light. Two scenarios for…