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Abstract To facilitate new studies of galaxy-merger-driven fueling of active galactic nuclei (AGNs), we present a catalog of 387 AGNs that we have identified in the final population of over 10,000z< 0.15 galaxies observed by the Sloan Digital Sky Survey-IV (SDSS-IV) integral field spectroscopy survey Mapping Nearby Galaxies at Apache Point Observatory (MaNGA). We selected the AGNs via mid-infrared Wide-field Infrared Survey Explorer colors, Swift/Burst Alert Telescope ultra-hard X-ray detections, NRAO Very Large Array Sky Survey and Faint Images of the Radio Sky at Twenty centimeters radio observations, and broad emission lines in SDSS spectra. By combining the MaNGA AGN catalog with a new SDSS catalog of galaxy mergers that were identified based on a suite of hydrodynamical simulations of merging galaxies, we study the link between galaxy mergers and nuclear activity for AGNs above a limiting bolometric luminosity of 1044.4erg s−1. We find an excess of AGNs in mergers, relative to nonmergers, for galaxies with stellar mass ∼1011M⊙, where the AGN excess is somewhat stronger in major mergers than in minor mergers. Further, when we combine minor and major mergers and sort by merger stage, we find that the highest AGN excess occurs in post-coalescence mergers in the highest-mass galaxies. However, we find no evidence of a correlation between galaxy mergers and AGN luminosity or accretion rate. In summary, while galaxy mergers overall do appear to trigger or enhance AGN activity more than nonmergers, they do not seem to induce higher levels of accretion or higher luminosities. We provide the MaNGA AGN Catalog and the MaNGA Galaxy Merger Catalog for the community here.
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A Catalog of Broad Hα and Hβ Active Galactic Nuclei in MaNGA
Abstract Broad Hαand Hβemission lines (FWHM > 1000 km s−1) are incredibly efficient tracers of the high-velocity clouds encircling active galactic nuclei (AGNs). As a result, we search for these broad-line AGN in the Sloan Digital Sky Survey’s Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) catalog. We identify 301 broad-line Hαgalaxies and 801 broad-line Hβgalaxies in the catalog. In total, we detect 1042 unique broad-line galaxies with luminosities between 1037and 1043erg s−1; 60 feature both broad Hαand broad Hβemission. We also determine that the broad-line region radius ranges between 0.01 and 46 lt-days, with a median radius of 0.1 lt-days (0.02 pc) for our broad Hβsample. In addition, we find that both samples feature a higher fraction of galaxy mergers (44% for the broad Hαsample and 43% for the broad Hβsample), compared to the full MaNGA galaxy sample (26%), which suggests that merger-driven fueling is strongly active in our sample.
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- PAR ID:
- 10601153
- Publisher / Repository:
- The Astrophysical Journal
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 971
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 92
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3847/1538-4357/ad4c68
