The Effects of Metallicity and AGN Activity on the Mid-Infrared Dust Emission of Galaxies

Abstract

Using a sample of the $Spitzer$ SWIRE-field galaxies whose optical spectra are taken from the Data Release 4 of the Sloan Digital Sky Survey, we study possible correlations between the Mid-InfraRed (MIR) dust emission from these galaxies and both their metallicities and AGN activities. We find that both metallicity and AGN activity are well correlated with the following ratios: PAH(Polycyclic Aromatic Hydrocarbon)-to-star, VSG(Very Small Grain)-to-star and PAH-to-VSG, which can be characterized by $\nu L_{\nu }[8\mu m(\mathrm{dust})]/\nu L_{\nu }[3.6\mu m]$, $\nu L_{\nu }[24\mu m]/\nu L_{\nu }[3.6\mu m]$, and$\nu L_{\nu }[8\mu m(\mathrm{dust})]/\nu L_{\nu }[24\mu m]$ respectively. We argue that our MIR-metallicity correlation could be explained by either the amount of dust (ongoing dust formation) or dust destruction (PAHs and VSGs could be destroyed by hard and intense radiation fields), and that the MIR-AGN correlation could arise due to either PAH destruction or an enhanced VSG continuum by the central AGN.

15 pages, 8 figures; accepted publication in ApJ

References in corpus (11)

• The Host Galaxies and Classification of Active Galactic Nuclei
• Infrared Emission from Interstellar Dust. IV. The Silicate-Graphite-PAH Model in the Post-Spitzer Era
• Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample
• Near-Infrared and Star-forming properties of Local Luminous Infrared Galaxies
• Mid-Infrared Spectral Diagnostics of Nuclear and Extra-Nuclear Regions in Nearby Galaxies
• The Spitzer Spirals, Bridges, and Tails Interacting Galaxy Survey: Interaction-Induced Star Formation in the Mid-Infrared
• Anomalously low PAH emission from low-luminosity galaxies
• Large-scale Star Formation Triggering in the Low-mass Arp 82 System: A Nearby Example of Galaxy Downsizing Based on UV/Optical/Mid-IR Imaging
• Multi-wavelength Study of Young Massive Star Clusters in the Interacting Galaxy ARP 24
• Mid-to-Far Infrared Spectral Energy Distribution of Galaxies in Spitzer First Look Survey Field
• PAHs in Galaxies: their Properties and Evolution

Cited by in corpus (14)

• Metallicity Effects on Dust Properties in Starbursting Galaxies
• High-resolution, 3D radiative transfer modeling : I. The grand-design spiral galaxy M51
• Starburst-AGN mixing: II. Optically-selected active galaxies
• The Herschel Exploitation of Local Galaxy Andromeda (HELGA) VII: A SKIRT radiative transfer model and insights on dust heating
• Mid-Infrared Spectroscopic Properties of Ultra-Luminous Infrared Quasars
• Star Formation Properties in Barred Galaxies(SFB). III. Statistical Study of Bar-driven Secular Evolution using a sample of nearby barred spirals
• High-resolution, 3D radiative transfer modelling IV. AGN-powered dust heating in NGC 1068
• Gas phase metallicity determinations in nearby AGNs with SDSS-IV MaNGA: evidence of metal poor accretion
• The Contribution of Evolved Stars to PAH Heating and Implications for Estimating Star Formation Rates
• Optical and infrared emission of H II complexes as a clue to the PAH life cycle
• Star Formation Properties in Barred Galaxies(SFB). I. Ultraviolet-to-Infrared Imaging and Spectroscopic Studies of NGC 7479
• A Systematic Analysis of Stellar Populations in the Host Galaxies of SDSS Type I QSOs
• A Statistical Study of H I Gas in Nearby Narrow-Line AGN-Hosting Galaxies
• The discrepancy in the mid-infrared continuum and the features of polycyclic aromatic hydrocarbons for Spitzer and Herschel SWIRE-field galaxies