ATTENZIONE! IL REPOSITORY E’ APERTO ESCLUSIVAMENTE ALL’IMMISSIONE DEI RAPPORTI TECNICI (COLLEZIONE 4.01). NON E’ POSSIBILE INSERIRE PRODOTTI IN TUTTE LE ALTRE COLLEZIONI, A CAUSA DI PROBLEMI TECNICI. THE REPOSITORY IS OPEN EXCLUSIVELY FOR THE SUBMISSION OF TECHNICAL REPORTS (COLLECTION 4.01). SUBMISSIONS TO ALL OTHER COLLECTIONS ARE TEMPORARILY UNAVAILABLE, DUE TO TECHNICAL ISSUES.
 

The Quasar Main Sequence Explained by the Combination of Eddington Ratio, Metallicity, and Orientation

Journal
Date Issued
2019
Author(s)
Panda, Swayamtrupta
•
•
Czerny, Bożena
DOI
Abstract
We address the effect of orientation of the accretion disk plane and the geometry of the broad-line region (BLR) as part of an effort to understand the distribution of quasars in optical plane of the quasar main sequence. We utilize the photoionization code CLOUDY to model the BLR incorporating the grossly underestimated form factor (f). Treating the aspect of viewing angle appropriately, we confirm the dependence of the R Fe II sequence on L/{L}Edd} and on the related observational trends—as a function of the SED shape, cloud density, and composition, verified from prior observations. Sources with R Fe II in the range 1-2 (about 10% of all quasars, the so-called extreme Population A [xA] quasars) are explained as sources of high, and possibly extreme Eddington ratio along the R Fe II sequence. This result has important implications for the exploitation of xA sources as distance indicators for cosmology. Fe II emitters with R Fe II > 2 are very rare (<1% of all type 1 quasars). Our approach also explains the rarity of these highest Fe II emitters as extreme xA sources, and constrains the viewing angle ranges with increasing Hβ FWHM.
Volume
882
Issue
2
Start page
79
Uri
Url
Issn Identifier
0004-637X
Ads BibCode
2019ApJ...882...79P
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Panda_2019_ApJ_882_79.pdf

Description
Pdf editoriale
Size

4.37 MB

Format

Adobe PDF

Checksum (MD5)

098d96ec4b90ae887398e2e68134fd91

Loading...
Thumbnail Image
Name

1905.01729.pdf

Description
postprint
Size

1.22 MB

Format

Adobe PDF

Checksum (MD5)

9103577995bf59dfd2c542bc1b477eb7