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arXiv · 1805.08655

The first 62 AGN observed with SDSS-IV MaNGA - II: resolved stellar populations

Nícolas Dullius Mallmann·Rogério Riffel·Thaisa Storchi-Bergmann·Sandro Barboza Rembold·Rogemar A. Riffel·Jaderson Schimoia·Luiz Nicolaci da Costa·Vladimir Ávila-Reese·Sebastian F. Sanchez·Alice D. Machado·Rafael Cirolini·Gabriele S. Ilha·Janaína C. do Nascimento
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Abstract

We present spatially resolved stellar population age maps, average radial profiles and gradients for the first 62 Active Galactic Nuclei (AGN) observed with SDSS-IV MaNGA to study the effects of the active nuclei on the star formation history of the host galaxies. These results, derived using the STARLIGHT code, are compared with a control sample of non-active galaxies matching the properties of the AGN hosts. We find that the fraction of young stellar populations (SP) in high-luminosity AGN is higher in the inner ($R \leq 0.5\,R_e$) regions when compared with the control sample; low-luminosity AGN, on the other hand, present very similar fractions of young stars to the control sample hosts for the entire studied range ($1\,R_e$). The fraction of intermediate age SP of the AGN hosts increases outwards, with a clear enhancement when compared with the control sample. The inner region of the galaxies (AGN and control galaxies) presents a dominant old SP, whose fraction decreases outwards. We also compare our results (differences between AGN and control galaxies) for the early and late-type hosts and find no significant differences. In summary, our results suggest that the most luminous AGN seems to have been triggered by a recent supply of gas that has also triggered recent star formation ($t\,\leq\,40\,Myrs$) in the central region.

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Nícolas Dullius Mallmann, Rogério Riffel, Thaisa Storchi-Bergmann, Sandro Barboza Rembold, Rogemar A. Riffel, Jaderson Schimoia, Luiz Nicolaci da Costa, Vladimir Ávila-Reese, Sebastian F. Sanchez, Alice D. Machado, Rafael Cirolini, Gabriele S. Ilha, Janaína C. do Nascimento. 2018-05-22. The first 62 AGN observed with SDSS-IV MaNGA - II: resolved stellar populations. https://doi.org/10.1093/mnras%2Fsty1364

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