相关论文: Bursts from internal shocks: is it really synchrot…
Galactic synchrotron emission is a potentially confusing foreground, both in total power and in polarization, to the Cosmic Microwave Background Radiation. It also contains much physical information in its own right. This review examines…
The basic mechanism responsible for radio emission in radio-loud active galactic nuclei (AGNs) is assumed to be synchrotron radiation. We suggest here that radio emission in radio-quiet objects is also due to synchrotron radiation of…
A list is presented of known extragalactic radio jets which also have associated X-ray emission. The canonical emission processes for the production of X-rays are reviewed and the sources are categorized on the basis of our current…
Using Monte Carlo simulations, we demonstrate photopion production from Fermi-accelerated protons and the resulting neutrino production in gamma-ray bursts. Unless internal shocks occur at quite large distance from the center, ultra…
The origin of prompt emission in $\gamma$-ray bursts (GRBs) is highly debated topic. The observed spectra are supposed to play a crucial role in constraining the location of the emitting region, the strength of the magnetic field and the…
We investigate a scenario of photons scattering by electrons within a relativistic outflow. The outflow is composed of discrete shells with different speeds. One shell emits radiation for a short duration. Some of this radiation is…
Multiwavelength observations of blazars such as Mrk 421 and Mrk 501 show that they exhibit strong short time variabilities in flare-like phenomena. Based on the homogeneous synchrotron self-Compton (SSC) model and assuming that time…
Recently, in a few case studies we demonstrated that gyrosynchrotron microwave emission can be detected directly from the acceleration region when the trapped electron component is insignificant. For the statistical study reported here, we…
A simple model for variability in relativistic plasma outflows is studied, in which nonthermal electrons are continuously and uniformly injected in the comoving frame over a time interval dt. The evolution of the electron distribution is…
The validity of the $E_{\rm p}$ - $E_{\rm iso}$ correlation in gamma-ray bursts and the possibility of explaining the prompt emission with internal shocks are highly debated questions. We study whether the $E_{\rm p}$ - $E_{\rm iso}$…
Fast radio bursts (FRB) can arise from synchrotron maser emission at ultra-relativistic magnetized shocks, such as produced by flare ejecta from young magnetars. We combine PIC simulation results for the synchrotron maser with the dynamics…
We present self consistent calculations of Synchrotron self Compton (SSC) radiation that takes place within the afterglow blast wave and External inverse Compton (EIC) radiation that takes place when flare photons (produced by an internal…
We construct models for gamma-ray bursts where the emission comes from internal shocks in a relativistic wind with a highly non uniform distribution of the Lorentz factor. We follow the evolution of the wind using a very simplified approach…
There is no consensus on the emission mechanism of $\gamma$-ray bursts (GRBs). A synchrotron model can produce $\gamma$-ray spectra with the empirical Band function form, from a piece-wise two-power-law electron energy distribution (2EPLS).…
Synchrotron radiation from accelerated electrons above the photosphere of a relativistic ejecta is a natural candidate for the dominant process for the prompt GRB emission. There is however a tension between the predicted low-energy…
The long-lasting tension between the observed spectra of gamma ray bursts (GRBs) and the predicted synchrotron emission spectrum might be solved if electrons do not completely cool. Evidence for incomplete cooling was recently found in…
We present detailed calculations of the prompt spectrum of gamma-ray bursts (GRBs) predicted within the fireball model framework, where emission is due to internal shocks in an expanding relativistic wind. Our time dependent numerical model…
The detection in 10 bursts of an optical counterpart emission (i.e. during the prompt GRB phase) that is 10-10000 brighter than the extrapolation of the burst spectrum to optical frequencies suggests a synchrotron self-Compton origin for…
We present a model of the spectra of gamma-ray emitting blazars in which a single homogeneous emission region both emits synchrotron photons directly and scatters them to high (gamma-ray) energy before emission (a ``synchrotron…
The polarization measurement is an important tool to probe the prompt emission mechanism in gamma-ray bursts (GRBs). The synchrotron photons can be scattered by cold electrons in the outflow via Compton scattering processes. The observed…