Related papers: Stochastic Acceleration and the Evolution of Spect…
The SED of blazars show significant curvature. In this paper, we study the curvature properties for a large sample of Fermi/LAT bright blazars based on quasi-simultaneous SED. Both SEDs of synchrotron and inverse Compton (IC) components are…
Curved broad-band spectral distributions of non-thermal sources like blazars are described well by a log-parabolic (LP) law where the second degree term measures the curvature. LP energy spectra can be obtained for relativistic electrons by…
The origin and evolution of spectral curvature in blazar spectral energy distribution (SED) is still unclear. Since the observed SED curvature is related to an intrinsic curvature in emitting electron energy distribution (EED), we study…
We analyse the influence of the stochastic particle acceleration for the evolution of the electron spectrum. We assume that all investigated spectra are generated inside a spherical, homogeneous source and also analyse the synchrotron and…
The X-ray spectral curvature of blazars is traditionally explained by an empirical log-parabola function characterized by three parameters, namely the flux, curvature and spectral index at a given energy. Since their exact relationship with…
Stochastic acceleration of nonthermal electrons is investigated in the context of hard photon spectra of blazars. It is well known that this acceleration mechanism can produce a hard electron spectrum of $m \equiv \partial \ln n_{\rm…
Context: Stochastic acceleration is thought to be a key mechanism in the energization of solar flare electrons. Aims: We study whether stochastic acceleration can reproduce the observed soft-hard-soft evolution of the spectral features of…
The spectral shape of the prompt emissions of gamma-ray bursts (GRBs) is typically expressed by the Band function: smooth joining of two power-law functions for high-energy and low-energy regions. To reveal the origin of the Band function,…
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 curvature in blazar spectrum has the potential to understand the particle dynamics in jets. We performed a detailed analysis of simultaneous Swift-XRT (0.3-10 keV) and NuSTAR (3-79 keV)} observations of Mkn 421. Our analysis of NuSTAR…
We examine the applicability of the stochastic electron acceleration to two high synchrotron peaked blazars, Mrk 421 and Mrk 501, assuming synchrotron self-Compton emission of gamma-rays. Our model considers an emitting region moving at…
We consider particle acceleration to high energy via diffusive shock acceleration in a simple, self-consistent shock in jet model for blazars. Electrons are assumed to be accelerated at a shock front in relativistic jets and radiate…
We model the acceleration of electrons at a shock front in a relativistic blazar jet and compute the radiation they emit in a post-shock region which contains a homogeneous magnetic field. The full space, time and momentum dependence of the…
Here we investigate some aspects of stochastic acceleration of ultrarelativistic electrons by magnetic turbulence. In particular, we discuss the steady-state energy spectra of particles undergoing momentum diffusion due to resonant…
The synchrotron hump of the high energy peaked blazars generally lies in the 0.1-10 keV range and such sources show extreme flux and spectral variability in X-ray bands. Various spectral studies showed that the X-ray spectra of high energy…
The broadband SEDs of blazars exhibit two broad spectral components, which in leptonic emission models are attributed to synchrotron radiation and synchrotron self-Compton (SSC) radiation of relativistic electrons. During high state phases,…
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…
Stochastic acceleration of electrons and protons by waves propagating parallel to the large scale magnetic fields of magnetized plasmas is studied with emphasis on the feasibility of accelerating particles from a thermal background to…
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…
We collect a large sample with a reliable redshift detected by the Fermi satellite after 10 years of data (4FGL-DR2), including blazars, $\gamma$-ray Narrow-line Seyfert 1 galaxies ($\gamma$NLS1s), and radio galaxies. The spectral energy…