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تسجيل مستخدم جديدExtended Coronal Emission Lines in Active Galactic Nuclei
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A. Rodriguez-Ardila
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VLT and NTT spectra are used to examine the nuclear and extended coronal line emission in a sample of well-known Seyfert 1 and 2 galaxies. The excellent spatial resolution obtained with VLT allowed us to map [SiVI] 1.963 $mu$m and [SiVII] 2.48 $mu$m on scales of up to 20 pc. Coronal line emission, extended to distances of $sim$100 pc, is detected in some of the lines analyzed, particularly in [FeX] 6374AA, [FeXI] 7891AA, and [SiVII] 2.48$mu$m. Most coronal lines are strongly asymmetric towards the blue and broader than low-ionization lines. This result is particularly important for Circinus, where previous observations had failed at detecting larger widths for high-ionization lines. Photoionization models are used to investigate the physical conditions and continuum luminosities necessary to produced the observed coronal emission. We found that an ionization parameter U> 0.10 is necessary to reproduce the observations, although the clouds should be located at distances < 30 pc.
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