2001/03/08 by M. Nikołajuk, Marek Nikolajuk, Nikolajuk, Marek +3
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #GNSS positioning and interference #Geophysics and Gravity Measurements #Ionosphere and magnetosphere dynamics #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0103128
20 pages, 9 figures, submitted to New Astronomy
arxiv created 2001/03/08 · openalex publication_date 2001/03/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We test the disk/corona model of Janiuk et al. (2000) against the composite mean optical/UV/soft X-ray spectrum of radio loud and radio quiet quasars from Laor et al. (1997) which applies to faint quasars. The model well represents the optical/UV continuum if the hardening of the locally emitted spectrum is included, with the color to effective temperature ratio f ∼ 2 in the inner 20-30 Schwarzschild radii. Comptonization seen in the soft X-ray band is well explained by the adopted corona model in the case of radio loud objects. However, this Comptonization is much stronger in radio quiet objects and additional ad hoc assumed Comptonizing medium must be present. We speculate that perhaps in both types of quasars there is a strong outflow of the hot plasma; this plasma is collimated in radio loud objects but not collimated in the radio quiet objects so it is present along the line of sight, serving as the required Comptonizing medium. Hard X-ray power law is not explained by the model and it may come from non-thermal component of electron plasma, as it is the case for galactic black holes in their soft states.