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In a two-component model, the total observed emissions are the sum of two contributions, namely a beamed one and an unbeamed one. The observed beamed emissions from a relativistic jet are strongly boosted due to the beaming effect while the observed unbeamed emissions are the same as that in the co-moving frame. In the X-ay band, it is hard to separate the beamed and the unbeamed emissions from observations. However, it is interesting to investigate the X-ray emissions applying the two-component model as in Kembhavi (Mon. Not. R. Astron. Soc. 264:683, 1993). In this work, a sample of 397 blazars with available X-ray data and radio core-dominance parameters are compiled and the method proposed by Kembhavi et al is adopted to separate the two components in the X-ray emissions, then we also discuss the difference between BL Lac objects and FSRQs. Our results show that: (1) The beamed emissions dominate the X-ray emissions. (2) The averaged X-ray core-dominance parameter in BL Lacertae objects is greater than that in FSRQs. (3) A correlation between X-ray spectral index and X-ray core-dominance parameter is obtained, which supports the unified scheme of BL Lac objects, FR type I galaxies and FR type II with galaxy morphology, FSRQs unified with FR type two quasars. [ABSTRACT FROM AUTHOR]

The origin of jets is one of the most important issues concerning active galactic nuclei, yet it has remained obscure. In this work, we made use of information from emission lines, spectral energy distributions, and Fermiâ€"LAT Îł -ray emission to construct a blazar sample that contains 667 sources. We note that jet power originations are different for BL Lacertae objects (BL Lacs) and flat-spectrum radio quasars (FSRQs). The correlation between jet power P jet and the normalized disk luminosity L Disk/ L Edd shows a slope of âˆ'1.77 for BL Lacs and a slope of 1.16 for FSRQs. The results seem to suggest that BL Lac jets are powered by extracting black hole (BH) rotation energy, while FSRQ jets are mostly powered by accretion disks. Meanwhile, we find the accretion ratio M ̇ / M ̇ Edd increases with the normalized Îł -ray luminosity. Based on this, we propose a dividing line, log (L BLR / L Edd) = 0.25 log (L Îł / L Edd) âˆ' 2.23 , to separate FSRQs and BL Lacs in the diagram of L BLR/ L Edd against L Îł / L Edd using a machine-learning method; the method gives an accuracy of 84.5%. In addition, we propose an empirical formula, M BH / M ☉ ≃ L Îł 0.65 / 21.46 , to estimate BH mass based on a strong correlation between Îł -ray luminosity and BH mass. Strong Îł -ray emission is typical in blazars, and the emission is always boosted by a Doppler-beaming effect. In this work, we generate a new method to estimate a lower limit of Doppler factor δ and give δ BL Lac = 7.94 and δ FSRQ = 11.55. [ABSTRACT FROM AUTHOR]