INVESTIGADORES
ALONSO GIRALDES Maria Sol
artículos
Título:
The impact of bars and interactions on optically selected AGNs in spiral galaxies
Autor/es:
SOL ALONSO , GEORGINA COLDWELL, FERNANDA DUPLANCIC, VALERIA MESA, AND DIEGO G. LAMBAS
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP SCIENCES S A
Referencias:
Lugar: Paris; Año: 2018 vol. 618 p. 149 - 152
ISSN:
0004-6361
Resumen:
Aims . With the aim of performing a suitable comparison of the internal process of galactic bars with respect to the external effect ofinteractions on driving gas toward the inner most region of the galaxies, we explored and compared the efficiency of both mechanismson central nuclear activity in optically selected active galactic nuclei (AGNs) in spiral galaxies.Methods . We selected homogeneous samples of barred AGNs and active objects residing in pair systems, derived from the SloanDigital Sky Survey (SDSS). In order to carry out a reliable comparison of both samples (AGNs in barred hosts in isolation and ingalaxy pairs), we selected spiral AGN galaxies with similar distributions of redshift, magnitude, stellar mass, color and stellar agepopulation from both catalogs. With the goal of providing an appropriate quantification of the influence of strong bars and interactionson nuclear activity, we also constructed a suitable control sample of unbarred spiral AGNs without a companion and with similar hostproperties to the other two samples.Results . We found that barred optically selected AGNs show an excess of nuclear activity (as derived from the Lum[OIII]) andaccretion rate onto a central black hole (R) with respect to AGNs in pairs. In addition, both samples show an excess of high values ofLum[OIII] and R with respect to unbarred AGNs in the control sample. We also found that the fractions of AGNs with powerful nuclearactivity and high accretion rates increase toward more massive hosts with bluer colors and younger stellar populations. Moreover,AGNs with bars exhibit a higher fraction of galaxies with powerful Lum[OIII] and efficient R with respect to AGN galaxies inhabitingpair systems, in bins of different galaxy properties. Regarding AGNs belonging to pair systems, we found that the central nuclearactivity is remarkably dependent on the galaxy pair companion features. The Lum[OIII] for AGNs in pairs is clearly enhanced whenthe galaxy companion exhibits a bright and more massive host with high metallicity, blue color, efficient star formation activity andyoung stellar population. The results of this work reveal an important capacity of both mechanisms, bars and interactions, to transportmaterial towards the galaxy central regions. In this context, it should also be noted that the internal process of the bar is more efficientat improving the central nuclear activity in AGN objects than that corresponding to the external mechanism of the galaxy?galaxyinteractions.