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Stratified Magnetically-Driven Accretion-Disk Winds and Their Relations to Jets

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 نشر من قبل Keigo Fukumura
 تاريخ النشر 2013
  مجال البحث فيزياء
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We explore the poloidal structure of two-dimensional (2D) MHD winds in relation to their potential association with the X-ray warm absorbers (WAs) and the highly-ionized ultra-fast outflows (UFOs) in AGN, in a single unifying approach. We present the density $n(r,theta)$, ionization parameter $xi(r,theta)$, and velocity structure $v(r,theta)$ of such ionized winds for typical values of their fluid-to-magnetic flux ratio, $F$, and specific angular momentum, $H$, for which wind solutions become super-Alfvenic. We explore the geometrical shape of winds for different values of these parameters and delineate the values that produce the widest and narrowest opening angles of these winds, quantities necessary in the determination of the statistics of AGN obscuration. We find that winds with smaller $H$ show a poloidal geometry of narrower opening angles with their Alfven surface at lower inclination angles and therefore they produce the highest line of sight (LoS) velocities for observers at higher latitudes with the respect to the disk plane. We further note a physical and spatial correlation between the X-ray WAs and UFOs that form along the same LoS to the observer but at different radii, $r$, and distinct values of $n$, $xi$ and $v$ consistent with the latest spectroscopic data of radio-quiet Seyfert galaxies. We also show that, at least in the case of 3C 111, the winds pressure is sufficient to contain the relativistic plasma responsible for its radio emission. Stratified MHD disk-winds could therefore serve as a unique means to understand and unify the diverse AGN outflows.



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