The Gamma-ray Emissions from BL Lac Objects

The γ-ray emission mechanism is still an open question. BL Lac objects are an extreme subclass of active galactic nuclei. In this paper, we have collected 22 BL Lacertae objects, and investigated the possible correlations between the γ-ray emission(maximum, minimum and average data) at 1 GeV and the radio emission at 8. 4GHz. Our results are as follows. For minimum γ-ray data, there is no correlation between the γ-ray and radio flux density;For maximum and average γ-ray data, there are correlations for the 22 BL Lac objects. In addition, there is a correlation between the γ-ray and radio spectral index. According to our analysis, we have proposed that the γ-rays are likely from the synchrotron self-compton process in this case.