The AGN contribution to the UV–FIR luminosities of interacting galaxies and its role in identifying the main sequence
Affiliation
Univ Arizona, Dept AstronUniv Arizona, Steward Observ
Issue Date
2020-09-15Keywords
techniques: photometrictechniques: spectroscopic
galaxies: active
galaxies: evolution
galaxies: interactions
galaxies: starburst
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OXFORD UNIV PRESSCitation
Ramos Padilla, A. F., Ashby, M. L. N., Smith, H. A., Martínez-Galarza, J. R., Beverage, A. G., Dietrich, J., ... & Weiner, A. S. (2020). The AGN contribution to the UV–FIR luminosities of interacting galaxies and its role in identifying the main sequence. Monthly Notices of the Royal Astronomical Society, 499(3), 4325-4369.Rights
© The Author(s) 2020. Published by Oxford University Press on behalf of The Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Emission from active galactic nuclei (AGNs) is known to play an important role in the evolution of many galaxies including luminous and ultraluminous systems (U/LIRGs), as well as merging systems. However, the extent, duration, and exact effects of its influence are still imperfectly understood. To assess the impact of AGNs on interacting systems, we present a spectral energy distribution (SED) analysis of a sample of 189 nearby galaxies. We gather and systematically re-reduce archival broad-band imaging mosaics from the ultraviolet to the far-infrared using data from GALEX, SDSS, 2MASS, IRAS, WISE, Spitzer, and Herschel. We use spectroscopy from Spitzer/IRS to obtain fluxes from fine-structure lines that trace star formation and AGN activity. Utilizing the SED modelling and fitting tool CIGALE, we derive the physical conditions of the interstellar medium, both in star-forming regions and in nuclear regions dominated by the AGN in these galaxies. We investigate how the star formation rates (SFRs) and the fractional AGN contributions (f(AGN)) depend on stellar mass, galaxy type, and merger stage. We find that luminous galaxies more massive than about 10(10) M-* are likely to deviate significantly from the conventional galaxy mainsequence relation. Interestingly, infrared AGN luminosity and stellar mass in this set of objects are much tighter than SFR and stellar mass. We find that buried AGNs may occupy a locus between bright starbursts and pure AGNs in the f(AGN)-[Ne v]/[Ne II] plane. We identify a modest correlation between f(AGN) and mergers in their later stages.Note
Open access articleISSN
0035-8711EISSN
1365-2966Version
Final published versionSponsors
National Aeronautics and Space AdministrationScopus Count
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Except where otherwise noted, this item's license is described as © The Author(s) 2020. Published by Oxford University Press on behalf of The Royal Astronomical Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).
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