Related papers: Accretion-to-jet energy conversion efficiency in G…
A rotating black hole probably powers ultrarelativistic jets in gamma-ray bursts, relativistic jets from some active galactic nuclei, and jets from some black hole x-ray binaries. Prior estimates of the power output of a black hole have…
We investigate the jet launching process from accretion disks extending our recent study (paper I) to a truly bipolar setup. We perform axisymmetric MHD simulations of the disk-jet interaction on a computational domain covering both…
The multi-wavelength non-thermal emission from the binary neutron star (BNS) merger GW170817 has raised a heated debate concerning the post-merger outflow structure. Both a relativistic structured jet viewed off-axis and a mildly…
Starting from the assumption that radio jets and accretion disks are symbiotic features present in radio loud and radio quiet quasars we scale the bulk power of radio jets with the accretion power by adding mass- and energy conservation of…
The recent advanced LIGO/Virgo detections of gravitational waves (GWs) from stellar binary black hole (BBH) mergers, in particular GW190521, which is potentially associated with a quasar, have stimulated renewed interest in active galactic…
The afterglow of GRB 170817A has been detected for more than three years, but the origin of the multi-band afterglow light curves remains under debate. A classical top-hat jet model is faced with difficulties in producing a shallow rise of…
The event GW170817/GRB 170817A, discovered via the successful joint observation of its gravitational wave radiation and its multi-wavelength electromagnetic counterparts, was the first definite "smoking-gun" from the merger of two neutron…
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…
We present the results of our year-long afterglow monitoring of GW170817, the first binary neutron star (NS) merger detected by advanced LIGO and advanced Virgo. New observations with the Australian Telescope Compact Array (ATCA) and the…
The afterglow of the binary neutron star merger GW170817 gave evidence for a structured relativistic jet and a link between such mergers and short gamma-ray bursts. Superluminal motion, found using radio very long baseline interferometry…
We consider an extreme case of disc accretion onto a gravitating centre when the viscosity in the disc is negligible. The angular momentum and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from…
Recent observations of the radio and NIR source Sgr A* reinforce the interpretation of the Galactic Center as a scaled down version of an AGN. The discovery of an elongated structure at 43 GHz and increasing evidence for the presence of an…
Short GRBs are produced by relativistic jets arising from binary NS-NS or NS-BH mergers. Since the detection of the first unambiguous off-axis GRB 170817A, we learned that energy distribution in the jet plays an important role in explaining…
The observational follow-up campaign of the gravitational wave (GW) multi-messenger event GW170817/GRB170817A has shown that the prompt $\gamma$-rays are consistent with a relativistic structured jet observed from a wide viewing angle…
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…
Detectable electromagnetic counterparts to gravitational waves from compact binary mergers can be produced by outflows from the black hole-accretion disk remnant during the first ten seconds after the merger. Two-dimensional axisymmetric…
The algorithms used by the ATLAS Collaboration during Run 2 of the Large Hadron Collider to identify jets containing $b$-hadrons are presented. The performance of the algorithms is evaluated in the simulation and the efficiency with which…
We study the dynamical effects of gravitational focusing by a binary companion on winds from late-type stars. In particular, we investigate the mass transfer and formation of accretion disks around the secondary in detached systems…
Short Gamma-Ray Bursts (GRBs) are known to be associated with binary neutron star (NSNS) or black hole-neutron star (BHNS) mergers. The detection of gravitational wave and its associated electromagnetic counterparts GW/GRB 170817A has shown…
A relativistic electron-positron ($e^{+}e^{-}$) pair wind from a rapidly rotating, strongly magnetized neutron star (NS) would interact with a gamma-ray burst (GRB) external shock and reshapes afterglow emission signatures. Assuming that…