Related papers: X-ray afterglows of gamma-ray bursts in the synchr…
The role of Compton cooling in the standard model for the afterglows of gamma-ray bursts is considered. When electrons cool by scattering off their own synchrotron photons, three cooling regimes are identified in which the observed…
We consider the effects of inverse Compton scattering of synchrotron photons from relativistic electrons in GRB afterglows. We compute the spectrum of the inverse Compton emission and find that it can dominate the total cooling rate of the…
We extend previous work on gamma-ray burst (GRB) afterglows involving hot thermal electrons at the base of a shock-accelerated tail. Using a physically-motivated electron distribution based on first-principles simulations, we compute…
Recent results of the hectic research activity about gamma-ray bursts will be reviewed, with emphasis about the emission processes at the origin of the observed gamma-rays. The conventional synchrotron shock scenario is found to have…
High energy emission (> tens MeV) of Gamma-Ray Bursts (GRBs) provides an important clue to understand the physical processes involved in GRBs, which may be correlated with the GRB early afterglow. A shallow decline phase has been well…
We compute the afterglow of gamma-ray bursts produced by purely electromagnetic outflows to see if it shows characteristic signatures differing from those obtained with the standard internal/external shock model. Using a simple approach for…
We present a self-consistent way of modeling synchrotron self-Compton (SSC) effects in gamma-ray burst afterglows, with and without approximated Klein-Nishina suppressed scattering. We provide an analytic approximation of our results, so…
We investigate two high energy radiation mechanisms, the proton synchrotron and the electron inverse Compton emission, and explore their possible signatures in the broad-band spectra and in the keV to GeV light curves of gamma-ray burst…
Aims: We investigate the behavior of the frequency-centered light curves expected within the standard model of Gamma Ray Bursts allowing the maximum electron energy to be a free parameter permitted to take low values. Methods: We solve the…
To date, nearly all multi-wavelength modeling of long-duration gamma-ray bursts has ignored synchrotron radiation from the significant population of electrons expected to pass the shock without acceleration into a power-law distribution. We…
I discuss some theoretical expectations for the synchrotron emission from a relativistic blast-wave interacting with the ambient medium, as a model for GRB afterglows, and compare them with observations. An afterglow flux evolving as a…
We numerically simulate the gamma-ray burst (GRB) afterglow emission with a one-zone time-dependent code. The temporal evolutions of the decelerating shocked shell and energy distributions of electrons and photons are consistently…
This paper introduces a kinetic code that simulates gamma-ray burst (GRB) afterglow emission from the external forward shock and presents examples of some of its applications. One interesting research topic discussed in the paper is the…
(abridged) Afterglow light curves are constructed analytically for realistic gamma-ray burst remnants decelerating in either a homogeneous interstellar medium or a stellar wind environment, taking into account the radiative loss of the…
The detection of a very-high-energy TeV spectral component in the afterglow emission of gamma-ray bursts (GRBs) has opened a new probe into the energetics of ultra-relativistic blast waves and the nature of the circumburst environment in…
In the standard synchrotron afterglow model, a power law of electrons is responsible for all aspects of photon production and absorption. Recent numerical work has shown that the vast majority of particles in the downstream medium are…
Scattering of the forward-shock synchrotron emission by a relativistic outflow located behind the leading blast-wave may produce an X-ray emission brighter than that coming directly from the forward-shock and may explain four features…
We study synchrotron self-inverse Compton radiation from a reverse-shocked fireball. If the inverse Compton process dominates the cooling of shocked electrons, an X-ray flare produced by the first order Compton scattering would emerge in…
In models for gamma ray burst afterglows, it is normally assumed that the external shock strongly amplifies the magnetic field and that this field maintains a steady value throughout the shocked region. We discuss the effects of modifying…
The detection of delayed X-ray, optical and radio emission, "afterglow", associated with $\gamma$-ray bursts (GRBs) is consistent with fireball models, where the emission are produced by relativistic expanding blast wave, driven by…