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تسجيل مستخدم جديدComparison of The UV and Optical Fe II Emission in Type 1 AGNs
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We present the kinematical properties of the UV and optical FeII emission gas based on the velocity shift and line width measurements of a sample of 223 Type 1 active galactic nuclei (AGNs) at 0.4 $<$ z $<$ 0.8. We find a strong correlation between the line widths of the UV and optical FeII emission lines, indicating that both FeII emission features arise from similar distances in the broad line region (BLR). However, in detail we find differing trends, depending on the width of FeII. While the velocity shifts and dispersions of the UV Fe II (FeUV) and optical Fe II (FeOPT) emission lines are comparable to each other for AGNs with relatively narrow FeOPT line widths (i.e., FWHM < 3200 kms; Group A), FeOPT is broader than FeUV for AGNs with relatively broad FeOPT (i.e., FWHM > 3200 kms; Group B). FeII emission lines are on average narrower than Hb and MgII for Group A, indicating the FeII emission region is further out in the BLR, while for Group B AGNs FeOPT is comparable to Hb and broader than MgII. While FeII emission lines are on average redshifted ($40pm141$ kms and $182pm95$, respectively for FeUV and FeOPT), indicating inflow, the sample as a whole shows a large range of velocity shifts, suggesting complex nature of gas kinematics.
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