The polarized signal from broad emission lines in AGNs
The polarized signal from broad emission lines in AGNs
复制标题
来自活动星系核中宽发射线的偏振信号
DOI：
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发表时间：
2019
影响因子：
4.8
通讯作者：
R. Cartier
中科院分区：
文献类型：
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作者：
P. Lira;R. Goosmann;M. Kishimoto;R. Cartier
利用stokes蒙特卡罗辐射传输码，我们重新研究了I型活动星系核中由于赤道散射而产生的圆盘状宽发射线区域（BLR）的光谱偏振信号的预测。我们重现了先前工作的发现，但仅针对比先前提出的光学和几何厚度大得多的散射体。我们还发现，当考虑散射体各区域的偏振发射时，偏振位角（PA）的摆动方向与最初提出的相反。此外，我们发现散射介质中存在外流可以显著改变观测到的线廓线，并且在径向外流风的存在下散射信号的PA增强。最后，当散射体与BLR共空间并径向流出时，可以看到一个特征不同的PA剖面，形状像“M”。
Using the stokes Monte Carlo radiative transfer code, we revisit the predictions of the spectropolarimetric signal from a disc-like broad emission line region (BLR) in type I active galactic nuclei due to equatorial scattering. We reproduce the findings of previous works, but only for a scatterer that is much more optically and geometrically thick than previously proposed. We also find that when taking into account the polarized emission from all regions of the scatterer, the swing of the polarization position angle (PA) is in the opposite direction to that originally proposed. Furthermore, we find that the presence of outflows in the scattering media can significantly change the observed line profiles, with the PA of the scattering signal being enhanced in the presence of radially outflowing winds. Finally, a characteristically different PA profile, shaped like an ‘M’, is seen when the scatterer is co-spatial with the BLR and radially outflowing.