Gemini NIFS survey of feeding and feedback processes in nearby active galaxies - VI. Stellar populations

Riffel, Rogerio; Dahmer-Hahn, Luis G.; Riffel, Rogemar A.; Storchi-Bergmann, Thaisa; Dametto, Natacha Z.; Davies, Richard; Burtscher, Leonard; Bianchin, Marina; Ruschel-Dutra, Daniel; Ricci, Claudio; Rosario, David J.

Abstract

We use Gemini Near-Infrared Integral Field Spectrograph (NIFS) adaptive optics assisted data cubes to map the stellar population of the inner few hundred parsec of a sample of 18 nearby Seyfert galaxies. The near-infrared light is dominated by the contribution of young to intermediate-age stellar populations, with light-weighted mean ages (L) less than or similar to 1.5 Gyr. Hot dust (HD) emission is centrally peaked (in the unresolved nucleus), but it is also needed to reproduce the continuum beyond the nucleus in nearly half of the sample. We have analysed the stellar population properties of the nuclear region and their relation with more global properties of the galaxies. We find a correlation between the X-ray luminosity and the contributions from the HD, featureless continuum (FC), and reddening Av. We attribute these correlations to the fact that all these properties are linked to the mass accretion rate to the active galactic nuclei (AGNs). We also find a correlation of the bolometric luminosity log(L-Bolobs) with the mass-weighted mean age of the stellar population, interpreted as due a delay between the formation of new stars and the triggering/feeding of the AGN. The gas reaching the supermassive black hole is probably originated from mass loss from the already somewhat evolved intermediate-age stellar population ((L) less than or similar to 1.5 Gyr). In summary, our results show that there is a significant fraction of young to intermediate-age stellar populations in the inner few 100 pc of active galaxies, suggesting that this region is facing a rejuvenation process in which the AGN, once triggered, precludes further star formation, in the sense that it can be associated with the lack of new star formation in the nuclear region.

Más información

Título según WOS: Gemini NIFS survey of feeding and feedback processes in nearby active galaxies - VI. Stellar populations
Título de la Revista: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volumen: 512
Número: 3
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2022
Página de inicio: 3906
Página final: 3921
DOI:

10.1093/MNRAS/STAC740

Notas: ISI