Related papers: Modeling long GRBs using a single shock with relat…
We present a detail analysis on the spectral lags of the short gamma-ray bursts (GRBs) and compare them with that of the long GRBs by using the CGRO/BATSE GRB Catalog. Our results are as follows. (1)The spectral lag distribution of the…
In this paper, radiating fluids scaling laws are studied. We focus on optically thin and optically thick regimes which are relevant for both astrophysics and laboratory experiments. By using homothetic Lie groups, we obtain the scaling…
Radiative corrections are studied within an extension of the standard model, containing extra singlet scalars. The calculations determine the effect of a large width of the Higgs boson on radiative corrections. They throw some light on the…
This paper summarizes recent progresses in our theoretical understanding of particle acceleration at relativistic shock waves and it discusses two salient consequences: (1) the maximal energy of accelerated particles; (2) the impact of the…
We present a possible Cepheid-like luminosity estimator for the long gamma-ray bursts based on the variability of their light curves. To construct the luminosity estimator, we use CGRO/BATSE data for 13 bursts, Wind/KONUS data for 5 bursts,…
The formulation of a universal theory for bulk viscosity and heat conduction represents a theoretical challenge for our understanding of relativistic fluid dynamics. Recently, it has been shown that the multifluid variational approach…
Gamma-ray burst (GRB) afterglows are well described by synchrotron emission originating from the interaction between a relativistic blast wave and the external medium surrounding the GRB progenitor. We introduce a code to reconstruct…
The relativistic hydrodynamical equations are being examined with the aim of extracting the quantum-mechanical equations (the relativistic Klein-Gordon equation and the Schr\"odinger equation in the non-relativistic limit). In both cases it…
We present new, exact, finite solutions of relativistic hydrodynamics for longitudinally expanding fireballs for arbitrary constant value of the speed of sound. These new solutions generalize earlier, longitudinally finite, exact solutions,…
We extend the standard model of forward-reverse shock (FS-RS) for gamma-ray burst (GRB) afterglow to more general cases. On one hand, we derive the analytical solution to the hydrodynamics of the shocks in two limiting cases, i.e., an…
Radiative transfer and radiation hydrodynamics use the relativistic Boltzmann equation to describe the kinetics of photons. It is difficult to solve the six-dimensional time-dependent transfer equation unless the problem is highly symmetric…
We investigate relativistic flows after a shock wave generated in a star arrives at the surface. First, the sphericity effect is involved through a successive approximation procedure by adding correction terms to an already known…
The structure of steady plane-parallel radiative shock waves propagating through the hydrogen gas undergoing partial ionization and excitation of bound atomic states is investigated in terms of the self-consistent solution of the equations…
Gamma-ray bursts (GRBs) serve as important cosmological probes, whose X-ray afterglow light curves (LCs) may exhibit a plateau phase (with temporal slope $\alpha$ between 0 and 0.5) that may originate from magnetar energy injection. Similar…
The hard X-ray and gamma-ray phenomenology of gamma-ray bursts (GRBs) can be explained by an external shock model where a single relativistic blast wave interacts with the surrounding medium. Besides reproducing the generic spectral…
Gamma Ray Bursts (GRB) observed up to redshifts $z>8$ are fascinating objects to study due to their still unexplained relativistic outburst mechanisms and a possible use to test cosmological models. Our analysis of 77 GRB afterglows with…
The fluctuations observed in the light curves of some GRB-afterglows (such as GRB 021004) provide a useful tool to probe the circum-burst density profile and to probe the variations in the energy of blast-wave with time. We present a…
Gamma-ray bursts (GRBs) are fascinating extragalactic objects. They represent a fantastic opportunity to investigate unique properties not exhibited in other sources. Multi-wavelength afterglow observations from some short- and…
We review recent interest in the relativistic Riemann problem as a method for generating a non-equilibrium steady state. In the version of the problem under con- sideration, the initial conditions consist of a planar interface between two…
Shocks are ubiquitous in astrophysical sources, many of which involve relativistic bulk motions, leading to the formation of relativistic shocks. Such relativistic shocks have so far been studied mainly in one dimension, for simplicity, but…