Blazars SED in Conical Plasma Flow : a Monte Carlo study
Abstract
Blazars host the most powerful persistent relativistic conical jet  a highly collimated anisotropic flow of material/plasma. Motivated by this, we explore the blazar's broadband spectral energy distribution (SED) in an anisotropic flow of plasma which emits via synchrotron and inverse Compton (IC) mechanism. The flow is conical with two velocity components: a highly relativistic flow component along the jet axis and a random perpendicular component with average random Lorentz factor $\langle \gamma^{ran} \rangle$ $<<$ than the average component along the jet axis $\langle \gamma \rangle$. Assuming a broken powerlaw electron population, we calculated the broadband SED using synchrotron and IC processes assuming a cylindrical (of radius R and length L) emission region. For the IC process, we used Monte Carlo approach. We found that such anisotropic flow can reproduce blazars broadband emission as well as general short and high amplitude variability, indicating that spectral and temporal variability are not sufficient to distinguish among existing models. We demonstrate this by reproducing SEDs of FSRQ 3C 454.3 and three BL Lacs objects OJ 287, S5 0716+714, PKS 2155304. Our formalism and setup also allow us to investigate the effect of the geometry and dimension of emission region on observed broadband spectra. We found that the SEDs of low synchrotron peak (LSP) blazar can be explained by considering only SSC (synchrotron selfCompton) if R/L ($<$ 0.01), broadly mimicking a spinesheath geometry. In general, the degeneracy between nonthermal particle number density and length of the emission region (L) allow us to reproduce any variability in terms of particle number density.
 Publication:

arXiv eprints
 Pub Date:
 June 2021
 DOI:
 10.48550/arXiv.2106.06263
 arXiv:
 arXiv:2106.06263
 Bibcode:
 2021arXiv210606263K
 Keywords:

 Astrophysics  High Energy Astrophysical Phenomena
 EPrint:
 22 pages, 11 figures