Time-dependent Radiation Transfer in the Internal Shock Model Scenario for Blazar Jets

We describe the time-dependent radiation transfer in blazar jets, within the internal shock model. We assume that the central engine, which consists of a black hole and an accretion disk, spews out relativistic shells of plasma with different velocity, mass, and energy. We consider a single inelastic collision between a faster (inner) and a slower (outer) moving shell. We study the dynamics of the collision and evaluate the subsequent emission of radiation via the synchrotron and synchrotron self Compton (SSC) processes after the interaction between the two shells has begun. The collision results in the formation of a forward shock (FS) and a reverse shock (RS) that convert the ordered bulk kinetic energy of the shells into magnetic field energy and accelerate the particles, which then radiate. We assume a cylindrical geometry for the emission region of the jet. We treat the self-consistent radiative transfer by taking into account the inhomogeneity in the photon density throughout the region. In this paper, we focus on understanding the effects of varying relevant input parameters on the simulated spectral energy distribution (SED) and spectral variability patterns.

Comments: Accepted for publication in ApJ. 22 figures, 50 pages in preprint format

Similar Publications

We study the inflationary perturbations in general (classically) scale-invariant theories. Such scenario is motivated by the hierarchy problem and provides natural inflationary potentials and dark matter candidates. We analyse in detail all sectors (the scalar, vector and tensor perturbations) giving general formul$\ae$ for the potentially observable power spectra, as well as for the curvature spectral index $n_s$ and the tensor-to-scalar ratio $r$. Read More


In this paper, we present a new method of measuring Hubble parameter($H(z)$), making use of the anisotropy of luminosity distance($d_{L}$), and the analysis of gravitational wave(GW) of neutron star(NS) binary system. The method has never been put into practice before due to the lack of the ability of detecting GW. LIGO's success in detecting GW of black hole(BH) binary system merger announced the possibility of this new method. Read More


We reanalyse the cosmic microwave background (CMB) Cold Spot (CS) anomaly with particular focus on understanding the bias a mask (to remove Galactic and point sources contamination) may introduce. We measure the coldest spot, found by applying the Spherical Mexican Hat Wavelet (SMHW) transform on 100,000 masked and unmasked CMB simulated maps. The coldest spot in masked maps is the same as in unmasked maps only 48% of the time, suggesting that false minima are more frequently measured in masked maps. Read More


Spin patterns of spiral galaxies can be broadly separated into galaxies with clockwise patterns and galaxies with counterclockwise spin patterns. While the differences between these patterns are visually noticeable, they are a matter of the perspective of the observer, and therefore in a sufficiently large universe no other differences are expected between galaxies with clockwise and counterclockwise spin patterns. Here large datasets of spiral galaxies separated by their spin patterns are used to show that spiral galaxies with clockwise spin patterns are photometrically different from spiral galaxies with counterclockwise patterns. Read More


We compute the power spectrum at one-loop order in standard perturbation theory for the matter density field to which a standard Lagrangian Baryonic acoustic oscillation (BAO) reconstruction technique is applied. The BAO reconstruction method corrects the bulk motion associated with the gravitational evolution using the inverse Zel'dovich approximation (ZA) for the smoothed density field. We find that the overall amplitude of one-loop contributions in the matter power spectrum substantially decrease after reconstruction. Read More


We present new numerical tools to analyse cosmic void catalogues, implemented inside the CosmoBolognaLib, a large set of Open Source C++/Python numerical libraries. The CosmoBolognaLib provides a common numerical environment for cosmological calculations. This work extends these libraries by adding new algorithms for cosmological analyses of cosmic voids, covering the existing gap between theory and observations. Read More


GRB 120323A is a very intense short Gamma Ray Burst (GRB) detected simultaneously during its prompt gamma-ray emission phase with the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope and the Konus experiment on board the Wind satellite. GBM and Konus operate in the keV--MeV regime, however, the GBM range is broader both toward the low and the high parts of the gamma-ray spectrum. Analysis of such bright events provide a unique opportunity to check the consistency of the data analysis as well as cross-calibrate the two instruments. Read More


We propose a new method for generating equilibrium models of spherical systems of collisionless particles that are finite in extent, but whose central regions resemble dark matter halos from cosmological simulations. This method involves iteratively removing unbound particles from a Navarro-Frenk-White profile truncated sharply at some radius. The resulting models are extremely stable, and thus provide a good starting point for N-body simulations of isolated halos. Read More


A full account of galaxy evolution in the context of LCDM cosmology requires measurements of the average star-formation rate (SFR) and cold gas abundance across cosmic time. Emission from the CO ladder traces cold gas, and [CII] fine structure emission at 158 um traces the SFR. Intensity mapping surveys the cumulative surface brightness of emitting lines as a function of redshift, rather than individual galaxies. Read More


We set limits on the presence of the synchrotron cosmic web through the cross-correlation of the 2.3 GHz S-PASS survey with a model of the local cosmic web derived from constrained magnetohydrodynamic (MHD) simulations. The MHD simulation assumes cosmologically seeded magnetic fields amplified during large-scale structure formation, and a population of relativistic electrons/positrons from proton-proton collisions within the intergalactic medium. Read More