Related papers: Modelling the spectral evolution of classical doub…
We have mapped the powerful radio galaxy Hercules A at six frequencies spanning 1295 to 8440 MHz using the VLA in all four configurations. Here we discuss the structure revealed in total intensity, spectral index, polarization, and…
The precise spectra of Cosmic Ray (CR) electrons and positrons have been published by the measurement of AMS-02. It is reasonable to regard the difference between the electrons and positrons spectra ( $\triangle \Phi= \Phi_{e^-}-\Phi_{e^+}$…
We study the acceleration and radiation of charged particles in the shock waves of supernova remnants using a recent version of the "box model". According to this, particles are accelerated in an energy-dependent region around the shock by…
The origin of the extended X-ray emission in the large-scale jets of active galactic nuclei (AGNs) poses challenges to conventional models of acceleration and emission. Although the electron synchrotron radiation is considered the most…
Diffusion of electrons in two-dimensional disordered systems with spin-orbit interactions is investigated numerically. Asymptotic behaviors of the second moment of the wave packet and of the temporal auto-correlation function are examined.…
The radio spectral index map of the Coma halo shows a progressive steepening of the spectral index with increasing radius. Such a steepening cannot be simply justified by models involving continuous injection of fresh particles in the Coma…
We investigate the correlations between spectral index, jet side and extent of the radio lobes for a sample of nearby FRII radio galaxies. In Dennett-Thorpe et al. (1997) we studied a sample of quasars and found that the high surface…
The transport of photons in steady, spherical, scattering flows is investigated. The moment equations are solved analytically for accretion onto a Schwarzschild black hole, taking into full account relativistic effects. We show that the…
A Double-Double Radio Galaxy (DDRG) is defined as consisting of a pair of double radio sources with a common centre. In this paper we present an analytical model in which the peculiar radio structure of DDRGs is caused by an interruption of…
Collisionless shocks are one of the most powerful particle accelerators in the Universe. In the heliosphere, type II solar radio bursts are signatures of electrons accelerated by collisionless shocks launched at the Sun. Spectral…
Stochastic acceleration of particles under a pressure balance condition can accommodate the universal $p^{-5}$ spectra observed under many different conditions in the inner heliosphere. In this model, in order to avoid an infinite build up…
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…
Nearby radio galaxies (RGs) of Fanaroff-Riley Class I (FR-I) are considered possible sites for the production of observed ultra-high-energy cosmic rays (UHECRs). Among those, some exhibit blazar-like inner jets, while others display…
The study of the broad-band emission of GHz-Peaked-Spectrum (GPS) radio galaxies is a powerful tool to investigate the physical processes taking place in the central, kpc-sized region of their active hosts, where the jets propagate and the…
We recently found that streaming cosmic rays (CRs) induce a resistive electric field that can accelerate secondary electrons produced by CR ionization. In this work, we study the evolution of the energy spectrum of secondary electrons by…
Current wide-area radio surveys are dominated by active galactic nuclei, yet many of these sources have no identified optical counterparts. Here we investigate whether one can constrain the nature and properties of these sources, using…
The spectral evolution characteristics of the prompt emission in gamma-ray bursts (GRBs) have been extensively studied, but detailed investigations of spectral evolution in a GRB flare remain lacking. In this work, we present the first…
The detection of very high-energy (VHE) afterglow emission of the gamma-ray burst (GRB) 221009A by the Large High Altitude Air Shower Observatory (LHAASO) provides a unique opportunity to probe particle acceleration in relativistic…
The Letter takes up a question of what radio emission is produced by electrons at the very acceleration site of a solar flare. Specifically, we calculate incoherent radio emission produced within two competing acceleration…
We present a first-principles model of pitch-angle and energy distribution function evolution as particles are sequentially accelerated by multiple flare magnetic islands. Data from magnetohydrodynamic (MHD) simulations of an eruptive…