相关论文: Klein-Nishina Effects on Optically Thin Synchrotro…
The X-ray observations of Mkn 421 show significant spectral curvature that can be reproduced by a log-parabola function. The spectra can also be fitted by an analytical model considering synchrotron emission from an electron distribution…
In an X-ray reflection spectrum, a tail-like spectral feature generated via Compton down-scattering, known as a Compton shoulder (CS), appears at the low-energy side of the iron K$\alpha$ line. Despite its great diagnostic potential, its…
Synchrotron emission is believed to be a major radiation mechanism during gamma-ray bursts' (GRBs) prompt emission phase. A significant drawback of this assumption is that the theoretical predicted spectrum, calculated within the framework…
We re-analyze the Chandra ACIS spectrum of the kpc-scale jet in PKS 0637-752 to investigate the possible low energy cutoff in the relativistic electron spectrum producing the non-thermal radiation in the scenario of inverse Compton emission…
The occurrence of the inverse Compton catastrophe when the synchrotron brightness temperature exceeds a threshold value, usually estimated to be 10^{12} K, appears to be in contradiction with observation because: (i) the threshold is…
We calculate the synchrotron and inverse-Compton emissions from pairs formed in GRB afterglows from high-energy photons (above 100 MeV), assuming a power-law photon spectrum C_nu ~ nu^{-2} and considering only the pairs generated from…
If the emission of gamma-ray bursts were due to the synchrotron process in the standard internal shock scenario, then the typical observed spectrum should have a slope F(nu) \propto nu^{-1/2}, which strongly conflicts with the much harder…
Using a semi-analytic model of non-linear diffusive shock acceleration, we model the spectrum of cosmic ray (CR) electrons accelerated by supernova remnants (SNRs). Because electrons experience synchrotron losses in the amplified magnetic…
Recent work by Risaliti et al.(1999) suggests that more than half of all Seyfert 2 galaxies in the local universe are Compton-thick (N_H > 10^24 cm^-2). This has implications for AGN synthesis models for the X-ray background (XRB), the…
The interpretation of Galactic synchrotron observations is complicated by the degeneracy between the strength of the magnetic field perpendicular to the line of sight (LOS), $B_\perp$, and the cosmic-ray electron (CRe) spectrum. Depending…
We consider in this paper the effect of synchrotron self-Compton process on X-ray afterglows of gamma-ray bursts. We find that for a wide range of parameter values, especially for the standard values which imply the energy in the electrons…
The quiet Sun, i.e. in its non-flaring state or non-flaring regions, emits thermal radiation from radio to ultraviolet. The quiet Sun produces also non-thermal radiation observed in gamma rays due to interactions of Galactic Cosmic Rays…
The multiwavelength observations of GRB afterglows, together with some high-performance particle-in-cell simulations, hint that the magnetic field may decay behind the shock front. In this work, we develop a numerical code to calculate the…
We investigate the synchrotron self-Compton process in a planar shell taking the shock structure into account. We find that the energy density of the seed photons could deviate from the one-zone estimate by order of unity depending on the…
The synchrotron radio maps of supernova remnants (SNRs) in uniform interstellar medium and interstellar magnetic field (ISMF) are analyzed, allowing different `sensitivity' of injection efficiency to the shock obliquity. The very-high…
The classical description of synchrotron radiation fails at large Lorentz factors, $\gamma$, for relativistic electrons crossing strong transverse magnetic fields $B$. In the rest frame of the electron this field is comparable to the…
We consider the radiative acceleration to relativistic bulk velocities of a cold, optically thin plasma which is exposed to an external source of gamma-rays. The flow is driven by radiative momentum input to the gas, the accelerating force…
The problem of the anisotropic Inverse Compton scattering between a monochromatic photon beam and relativistic electrons is revisited and formally solved without approximations. Solutions are given for the single scattering with an electron…
Synchrotron self-Compton (SSC) process in the reverse shocks of gamma-ray bursts is suggested to be responsible for the observed prompt high-energy gamma-ray emissions from several gamma-ray bursts. We find that the SSC emission from the…
We present the XMM-Newton RGS and EPIC pn spectra of a long (\simeq 100 ks) observation of one of the soft X-ray brightest Compton-thick Seyfert 2 galaxies, NGC 424. As a first step, we performed a phenomenological analysis of the data to…