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Title: A Catalog of 71 Coronal Line Galaxies in MaNGA: [Ne v] Is an Effective AGN Tracer
Abstract Despite the importance of active galactic nuclei (AGNs) in galaxy evolution, accurate AGN identification is often challenging, as common AGN diagnostics can be confused by contributions from star formation and other effects (e.g., Baldwin–Phillips–Terlevich diagrams). However, one promising avenue for identifying AGNs is “coronal emission lines” (“CLs”), which are highly ionized species of gas with ionization potentials ≥100 eV. These CLs may serve as excellent signatures for the strong ionizing continuum of AGNs. To determine if CLs are in fact strong AGN tracers, we assemble and analyze the largest catalog of optical CL galaxies using the Sloan Digital Sky Survey's Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) catalog. We detect CL emission in 71 MaNGA galaxies, out of the 10,010 unique galaxies from the final MaNGA catalog, with ≥5 σ confidence. In our sample, we measure [Ne v ] λ 3347, λ 3427, [Fe vii ] λ 3586, λ 3760, λ 6086, and [Fe x ] λ 6374 emission and crossmatch the CL galaxies with a catalog of AGNs that were confirmed with broad-line, X-ray, IR, and radio observations. We find that [Ne v ] emission, compared to [Fe vii ] and [Fe x ] emission, is best at identifying high-luminosity AGNs. Moreover, we find that the CL galaxies with the least dust extinction yield the most iron CL detections. We posit that the bulk of the iron CLs are destroyed by dust grains in the galaxies with the highest [O iii ] luminosities in our sample, and that AGNs in the galaxies with low [O iii ] luminosities are possibly too weak to be detected using traditional techniques.  more » « less
Award ID(s):
1847938 1714503
PAR ID:
10435045
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
945
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
127
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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