The debeamed luminosity, sychrotron peak frequency and black hole mass of BL Lac objects

TL;DR

This study estimates intrinsic luminosities and synchrotron peak frequencies of 170 BL Lac objects, revealing correlations that support unification models and suggest more powerful sources have higher peak frequencies and heavier black holes.

Contribution

It provides the first comprehensive analysis of debeamed luminosities and their relation to black hole mass and peak frequency in BL Lac objects, supporting unification theories.

Findings

Debeamed luminosities follow FR I galaxy correlations.

Positive correlation between luminosity and peak frequency.

More powerful sources tend to have heavier black holes.

Abstract

We estimate the intrinsic luminosities and synchrotron peak frequency using the derived Doppler factor for a sample of 170 BL Lac objects, of which the synchrotron peak frequency are derived by fitting the SED constructed with the collected multi-band data from literatures. We find that the debeamed radio and optical core luminosities follow the same correlation found for FR I radio galaxies, which is in support of the unification of the BL Lac objects and the FR I galaxies based on orientation. For the debeamed luminosity at synchrotron peak frequency, we find a significant positive correlation between the luminosity and intrinsic synchrotron peak frequency. This implies that the more powerful sources may have the majority of jet emission at higher frequency. At synchrotron peak frequency, the intrinsic luminosity and black hole mass show strong positive correlation, while mild correlation is found in the case of jet power, indicating that the more powerful sources may have heavier black hole.