New mechanism of radiation polarization in type 1 Seyfert active galactic nuclei
العنوان: | New mechanism of radiation polarization in type 1 Seyfert active galactic nuclei |
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المؤلفون: | S. D. Buliga, M. Yu. Piotrovich, Yu. N. Gnedin, T. M. Natsvlishvili, N. A. Silant'ev |
المصدر: | Monthly Notices of the Royal Astronomical Society. 462:2-11 |
بيانات النشر: | Oxford University Press (OUP), 2016. |
سنة النشر: | 2016 |
مصطلحات موضوعية: | Physics, Active galactic nucleus, 010308 nuclear & particles physics, Scattering, Polarization in astronomy, Astrophysics::High Energy Astrophysical Phenomena, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Position angle, Polarization (waves), 01 natural sciences, Magnetic field, symbols.namesake, Space and Planetary Science, 0103 physical sciences, Faraday effect, symbols, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Circular polarization |
الوصف: | In most of Seyfert-1 active galactic nucei (AGN) the optical linear continuum polarization degree is usually small (less than 1%) and the polarization position angle is nearly parallel to the AGN radio-axis. However, there are many types-1 AGNs with unexplained intermediate values for both positional angles and polarization degrees. Our explanation of polarization degree and positional angle of Seyfert-1 AGNs focuses on the reflection of non-polarized radiation from sub-parsec jets in optically thick accretion discs. The presence of a magnetic field surrounding the scattering media will induce Faraday rotation of the polarization plane that may explain the intermediate values of positional angles if there is a magnetic field component normal to the accretion disc. The Faraday rotation depolarization effect in disc diminishes the competition between polarization of the reflected radiation with the parallel component of polarization and the perpendicular polarization from internal radiation of disc (the Milne problem) in favor of polarization of reflected radiation. This effect allows us to explain the observed polarization of Seyfert-1 AGN radiation even though the jet optical luminosity is much lower than the luminosity of disc. We present the calculation of polarization degrees for a number of Seyfert-1 AGNs. |
تدمد: | 1365-2966 0035-8711 |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::52da06113464eb48c05babb5f754367d https://doi.org/10.1093/mnras/stw1573 |
حقوق: | OPEN |
رقم الأكسشن: | edsair.doi...........52da06113464eb48c05babb5f754367d |
قاعدة البيانات: | OpenAIRE |
تدمد: | 13652966 00358711 |
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