Multi-Frequency Study of Spectral Indices of BL Lacertae Objects and Flat Spectrum Radio Quasars
Autor: | A. A. Ubachukwu, E. U. Iyida, A. E. Chukwude, F. C. Odo |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
Physics
High Energy Astrophysical Phenomena (astro-ph.HE) Astrophysics::High Energy Astrophysical Phenomena Spectrum (functional analysis) Significant difference Spectral properties Spectral density FOS: Physical sciences Astronomy and Astrophysics Quasar Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics - Astrophysics of Galaxies Spectral line Large sample Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Blazar Astrophysics - High Energy Astrophysical Phenomena Instrumentation |
Popis: | We present statistical analyses of a large homogenous data sample of Fermi-detected blazars thoroughly studied in order to reassess the relationship between flat-spectrum radio quasars (FSRQs) and subclasses of BL Lacertae objects (BL Lacs) blazar populations. We discovered from the average values of gamma-ray and X-ray spectral indices that the sequence of distribution is indicative of the blazar orientation scheme. Analyses of FSRQs and BL Lacs data show difference in the shape of gamma-ray and X-ray indices: significant anti-correlation (r~ greater than - 0.79) exists between gamma-ray and X-ray spectral indices. The spectral energy distributions of the blazar subclasses show that FSRQs and BL Lacs have similar spectral properties which can be unified through an evolutionary sequence. Nevertheless, there is a significant difference between the shapes of X-ray and gamma-ray spectra of blazars suggesting that different mechanisms are responsible for spectral variations in the two energy bands. All these results suggest that there is a form of a unified scheme for all blazars. 18 pages, 11 figures, 2 Tables. Accepted for Publication in New Astronomy |
Databáze: | OpenAIRE |
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