Related papers: Dynamics and stability of relativistic GRB blast w…
We consider a model in which the ultra-relativistic jet in a gamma-ray burst (GRB) is cold and magnetically accelerated. We assume that the energy flux in the outflowing material is partially thermalized via internal shocks or a reverse…
We perform three-dimensional numerical simulations of relativistic (with a Lorentz factor of 10), non magnetized jets propagating in a uniform density environment, in order to study the effect of the entrainment and the consequent…
Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microquasar systems usually have power-law emission spectra. Recent…
We have found that the conventional generic dynamical model for gamma-ray bursts (GRBs) cannot reproduce the Sedov solution in the non-relativistic limit. Based on our refined generic dynamical model, we investigate afterglows from jetted…
The relative strength between forward and reverse shock emission in early gamma-ray burst afterglow reflects that of magnetic energy densities in the two shock regions. We numerically show that with the current standard treatment, the…
We present a general formulation of special-relativistic magnetohydrodynamics and derive exact radially self-similar solutions for axisymmetric outflows from strongly magnetized, rotating compact objects. We generalize previous work by…
We study the gravitational wave (GW) production in extremely strong first order phase transitions where the latent heat density dominates the plasma energy density, $\alpha \gtrsim 1$. In such transitions, bubbles develop extremely thin and…
We investigate the linear stability of a hydrodynamic relativistic flow of magnetized plasma in the force--free approximation. We considered the case of light cylindrical jet in cold and dense environment, so the jet boundary remains at…
In this study, the light curves and spectrum of the photospheric thermal radiation from ultrarelativistic gamma-ray burst (GRB) jets are calculated using 2D relativistic hydrodynamic simulations of jets from a collapsar. As the jet…
(Please note that the abstract has been significantly shorted) We investigate Gamma-ray Burst (GRB) internal shocks with moderate magnetization, with the magnetization parameter $\sigma$ ranging from 0.001 to 10. Possible magnetic…
New two- and three-dimensional calculations are presented of relativistic jet propagation and break out in massive Wolf-Rayet stars. Such jets are thought responsible for gamma-ray bursts. As it erupts, the jet is surrounded by a cocoon of…
Many previous studies have determined that the long lasting emission at X-ray, optical and radio wavelengths from gamma-ray bursts (GRBs), called the afterglow, is likely produced by the external forward shock model. In this model, the GRB…
Afterglows of gamma-ray bursts often show flares, plateaus, and sudden intensity drops: these temporal features are difficult to explain as coming from the forward shock. We calculate radiative properties of early GRB afterglows with the…
Gamma-ray bursts (GRBs) are luminous stellar explosions characterized by the ejection of relativistic jets. This work proposes a novel paradigm to study these GRB jets. By analyzing the timing information of prompt pulses and X-ray flares,…
Fast reconnection operating in magnetically dominated plasmas is often invoked in models for magnetar giant flares, for magnetic dissipation in pulsar winds, or to explain the gamma-ray flares observed in the Crab nebula, hence its…
Long duration gamma-ray bursts (GRB) are at cosmological distance, they appear to be located near star forming regions, and are likely associated with some type of supernovae. They are also likely to be strongly beamed, which lowers their…
A long-duration gamma-ray burst (GRB) has been widely thought to arise from the collapse of a massive star, and it has been suggested that its ambient medium is a homogenous interstellar medium (ISM) or a stellar wind. There are two shocks…
The radiation drag in photon-rich environments of cosmic explosions can seed kinetic instabilities by inducing velocity spreads between relativistically streaming plasma components. Such microturbulence is likely imprinted on the breakout…
Transverse stratification is a common intrinsic feature of astrophysical jets. There is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis, surrounded by a slower, denser, extended jet. The…
A large variety of explosions result in mildly or ultra relativistic shock breakouts. Here we calculate the luminosity and spectrum that these breakouts produce. In order to do so we improve an analytic description of relativistic radiation…