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A Catalog of 406 AGNs in MaNGA: A Connection between Radio-mode AGN and Star Formation Quenching

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 نشر من قبل Julia Comerford
 تاريخ النشر 2020
  مجال البحث فيزياء
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Accurate active galactic nucleus (AGN) identifications and spatially resolved host galaxy properties are a powerful combination for studies of the role of AGNs and AGN feedback in the coevolution of galaxies and their central supermassive black holes. Here, we present robust identifications of 406 AGNs in the first 6261 galaxies observed by the integral field spectroscopy survey Mapping Nearby Galaxies at Apache Point Observatory (MaNGA). Instead of using optical line flux ratios, which can be difficult to interpret in light of the effects of shocks and metallicity, we identify the AGNs via mid-infrared WISE colors, Swift/BAT ultra hard X-ray detections, NVSS and FIRST radio observations, and broad emission lines in SDSS spectra. We subdivide the AGNs into radio-quiet and radio-mode AGNs, and examine the correlations of the AGN classes with host galaxy star formation rates and stellar populations. When compared to the radio-quiet AGN host galaxies, we find that the radio-mode AGN host galaxies reside preferentially in elliptical galaxies, lie further beneath the star-forming main sequence (with lower star formation rates at fixed galaxy mass), have older stellar populations, and have more negative stellar age gradients with galactocentric distance (indicating inside-out quenching of star formation). These results establish a connection between radio-mode AGNs and the suppression of star formation.

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