The Intrinsic Properties of Multiwavelength Energy Spectra for Fermi Teraelectronvolt Blazars

TL;DR

This study analyzes the multiwavelength energy spectra of 64 TeV blazars, revealing correlations between spectral features and physical parameters, advancing understanding of blazar emission mechanisms.

Contribution

It provides a comprehensive analysis of intrinsic properties and correlations in TeV blazars using spectral energy distribution fitting, which is novel in this specific context.

Findings

Strong correlation between synchrotron and IC peak frequencies.

Negative correlation between spectral index and peak frequency.

Correlation between luminosities and peak Lorentz factor.

Abstract

In this paper, we have selected a sample of 64 teraelectronvolt blazars, with redshift, from those classified in the fourth Fermi Large Area Telescope source catalog\footnote{\url{https://fermi.gsfc.nasa.gov/ssc/data/access/lat/8yr_catalog/}}. We have obtained the values of the relevant physical parameters by performing a log-parabolic fitting of the average-state multiwavelength spectral energy distributions. We estimate the range of the radiation zone parameters, such as the Doppler factor (${D}$), the magnetic field strength ($B$), the radiative zone radius ($R$) and the peak Lorentz factor (${\gamma _{\rm p}}$) of nonthermal electrons. Here, we show that (1) there is a strong linear positive correlation between the intrinsic synchrotron peak frequency and the intrinsic inverse Compton scattering (ICs) peak frequency among different types of blazars; (2) if radio bands are excluded, the spectral index of each band is negatively correlated with the intrinsic peak frequency; (3) there is a strong linear negative correlation between the curvature at the peak and the intrinsic peak frequency of the synchrotron bump, and a weak positive correlation between the curvature at the peak and the intrinsic peak frequency of the ICs bump; (4) there is a strong linear positive correlation between the intrinsic ICs peak luminosity and intrinsic $\gamma$-ray luminosity and between the intrinsic ICs peak frequency and peak Lorentz factor; (5) there is a strong negative linear correlation between $\rm log{\;B}$ and $\rm log{\;\gamma_{p}}$; and (6) there is no correlation between $\rm log{\;R}$ and $\rm log{\;\gamma_{p}}$.