A study of Intrinsic ${\hat{I}}^3$-ray Emission for {\it Fermi}/LAT-detected BL Lacs

Abstract

BL Lacs are one subclass of blazars with highly energetic ${\hat{I}}^3$-ray emission, which is strongly boosted by a relativistic beaming effect. The latest catalogue of the 10 years of {\it Fermi}/LAT data Abdollahi et al. (2020) and the ${\hat{I}}^3$-ray Doppler factors in Pei et al. (2020) provide us with a large BL Lac sample to study their jet emission morphologies and intrinsic properties. In this paper, we collected a sample of 294 {\it Fermi} BL Lacs and probed the correlations between the ${\hat{I}}^3$-ray emissions and luminosity distances. Our analyses give following conclusions: (1) the observed ${\hat{I}}^3$-ray emissions are really boosted by the ${\hat{I}}^3$-ray Doppler factor, and the intrinsic ${\hat{I}}^3$-ray emissions are closely correlated with luminosity distances. (2) the morphology of jet emissions for HBLs may be continuous, while that for IBLs may be the case of a moving sphere in the ${\hat{I}}^3$-ray bands.

8 pages, 6 figures, 2 tables. Accepted by Ap&SS