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Active Galactic Nuclei signatures in Red Geyser galaxies from Gemini GMOS-IFU observations

Astrophysics of Galaxies 2022-08-24 v3

Abstract

Red Geysers are quiescent galaxies with galactic scale ionised outflows, likely due to low-luminosity Active Galactic Nuclei (AGN). We used Gemini GMOS-IFU observations of the inner 1.03.0\sim 1.0-3.0 kpc of nine Red Geysers selected from the MaNGA survey to study the gas ionisation and kinematics. The emission-line ratios suggest the presence of Seyfert/LINER (Low Ionisation Nuclear Emission Region) nuclei in all sources. Two galaxies show Hα\alpha equivalent width (Hα\alpha EW) larger than 3 \AA (indicative of AGN ionisation) within an aperture 2.5 arcsec of diameter (1.33.71.3-3.7 kpc at the distance of galaxies) for MaNGA data, while with the higher resolution GMOS data, four galaxies present Hα\alpha EW>3>3 \AA within an aperture equal to the angular resolution (0.30.90.3-0.9 kpc). For two objects with GMOS-IFU data, the Hα\alpha EW is lower than 3 \AA but larger than 1.5 \AA, most probably due to a faint AGN. The spatially resolved electron density maps show values between 1003000100-3000 cm3^{-3} and are consistent with those determined in other studies. The large (MaNGA) and the nuclear scale (GMOS-IFU) gas velocity fields are misaligned, with a kinematic position angle difference between 12^{\circ} and 60^{\circ}. The [NII]λ\lambda6583 emission-line profiles are asymmetrical, with blue wings on the redshifted side of the velocity field and red wings on the blueshifted side. Our results support previous indications that the gas in Red Geysers is ionised by an AGN, at least in their central region, with the presence of outflows, likely originating in a precessing accretion disc.

Keywords

Cite

@article{arxiv.2208.03383,
  title  = {Active Galactic Nuclei signatures in Red Geyser galaxies from Gemini GMOS-IFU observations},
  author = {G. S. Ilha and R. A. Riffel and T. V. Ricci and S. B. Rembold and T. Storchi-Bergmann and R. Riffel and N. Roy and K. Bundy and R. Nemmen and J. S. Schimoia and L. N. da Costa},
  journal= {arXiv preprint arXiv:2208.03383},
  year   = {2022}
}

Comments

Accepted for publication in August 3, 2022