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arXiv · 2307.11474

Mapping the stellar population and gas excitation of MaNGA galaxies with MEGACUBES. Results for AGN versus control sample

Rogério Riffel·Nicolas D. Mallmann·Sandro B. Rembold·Gabriele S. Ilha·Rogemar A. Riffel·Thaisa Storchi-Bergmann·Daniel Ruschel-Dutra·Alexandre Vazdekis·Ignacio Martín-Navarro·Jaderson S. Schimoia·Cristina Ramos Almeida·Luiz N. da Costa·Glauber C. Vila-Verde·Lara Gatto
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Abstract

We present spaxel-by-spaxel stellar population fits for the $\sim$10 thousand MaNGA datacubes. We provide multiple extension fits files, nominated as MEGACUBES, with maps of several properties as well as emission-line profiles that are provided for each spaxel. All the MEGACUBES are available through a web interface (\url{https://manga.linea.org.br/} or \url{http://www.if.ufrgs.br/~riffel/software/megacubes/}). We also defined a final Active Galactic Nuclei (AGN) sample, as well as a control sample matching the AGN host galaxy properties. We have analysed the stellar populations and spatially resolved emission-line diagnostic diagrams of these AGNs and compared them with the control galaxies sample. We find that the relative fractions of young ($t \leq $56 Myr) and intermediate-age (100 Myr $\leq t \leq$ 2 Gyr) show predominantly a positive gradient for both AGNs and controls. The relative fraction of intermediate-age stellar population is higher in AGN hosts when compared to the control sample, and this difference becomes larger for higher [O III] luminosity AGNs. We attribute this to the fact that extra gas is available in these more luminous sources and that it most likely originates from mass-loss from the intermediate-age stars. The spatially resolved diagnostic diagrams reveal that the AGN emission is concentrated in the inner 0.5 $R_e$ (effective radius) region of the galaxies, showing that the AGN classification is aperture dependent and that emission-line ratios have to be taken together with the H$\alpha$ equivalent width for proper activity classification. We present a composite ``BPT+WHAN" diagram that produces a more comprehensive mapping of the gas excitation.

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Rogério Riffel, Nicolas D. Mallmann, Sandro B. Rembold, Gabriele S. Ilha, Rogemar A. Riffel, Thaisa Storchi-Bergmann, Daniel Ruschel-Dutra, Alexandre Vazdekis, Ignacio Martín-Navarro, Jaderson S. Schimoia, Cristina Ramos Almeida, Luiz N. da Costa, Glauber C. Vila-Verde, Lara Gatto. 2023-07-21. Mapping the stellar population and gas excitation of MaNGA galaxies with MEGACUBES. Results for AGN versus control sample. https://doi.org/10.1093/mnras/stad2234

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