http://arxiv.org/abs/2004.13113
I analyse the emitting regions for the optical Fe II and near-infrared Ca II emission pertaining to the broad-line region in active galaxies, using the CLOUDY photoionisation modelling to ascertain the tight correlation shown between these species. I explicitly show the connection between two physical quantities, i.e. metallicity in the BLR cloud, and, the cloud column density (N$_{\rm{H}}$) highlighting the co-dependence between them suggesting that even strong Fe II emitters, such as I Zw 1 can be modelled with metallicities that do not require values as high as shown from previous studies. The study suggests that the bulk of the Ca II emitting region is located farther in the BLR by a factor ~3 times as compared to the bulk Fe II emitting region.
S. Panda
Wed, 29 Apr 20
39/75
Comments: 20 pages, 18 figures, submitted to ApJ (comments are welcome)