The complex evolutionary paths of local infrared bright galaxies: A high-angular resolution mid-infrared view

A. Alonso-Herrero, R. Poulton, P. F. Roche, A. Hernán-Caballero, I. Aretxaga, M. Martínez-Paredes, C. Ramos Almeida, M. Pereira-Santaella, T. Díaz-Santos, N. A. Levenson, C. Packham, L. Colina, P. Esquej, O. González-Martín, K. Ichikawa, M. Imanishi, J. M. Rodríguez Espinosa, C. Telesco

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We investigate the evolutionary connection between local infrared (IR)-bright galaxies (log LIR ≥ 11.4 L) and quasars. We use high-angular resolution (~0.3-0.4 arcsec ~ few hundred parsecs) 8-13 μm ground-based spectroscopy to disentangle the active galactic nuclei (AGN) mid-IR properties from those of star formation. The comparison between the nuclear 11.3 μm polycyclic aromatic hydrocarbon feature emission and that measured with Spitzer/Spitzer Infrared Spectrograph indicates that the star formation is extended over a few kpc in the IR-bright galaxies. The AGN contribution to the total IR luminosity of IR-bright galaxies is lower than in quasars. Although the dust distribution is predicted to change as IR-bright galaxies evolve to IR-bright quasars and then to optical quasars, we show that the AGN mid-IR emission of all the quasars in our sample is not significantly different. In contrast, the nuclear emission of IR-bright galaxies with low AGN contributions appears more heavily embedded in dust although there is no clear trend with the interaction stage or projected nuclear separation. This suggests that the changes in the distribution of the nuclear obscuring material may be taking place rapidly and at different interaction stages washing out the evidence of an evolutionary path. When compared to normal AGN, the nuclear star formation activity of quasars appears to be dimming, whereas it is enhanced in some IR-bright nuclei, suggesting that the latter are in an earlier star formation-dominated phase.

Original languageEnglish
Pages (from-to)2405-2424
Number of pages20
JournalMonthly Notices of the Royal Astronomical Society
Volume463
Issue number3
DOIs
Publication statusPublished - 2016

Keywords

  • Galaxies: active
  • Galaxies: evolution
  • Galaxies: seyfert
  • Infrared: galaxies
  • Quasars: general

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'The complex evolutionary paths of local infrared bright galaxies: A high-angular resolution mid-infrared view'. Together they form a unique fingerprint.

  • Cite this

    Alonso-Herrero, A., Poulton, R., Roche, P. F., Hernán-Caballero, A., Aretxaga, I., Martínez-Paredes, M., Ramos Almeida, C., Pereira-Santaella, M., Díaz-Santos, T., Levenson, N. A., Packham, C., Colina, L., Esquej, P., González-Martín, O., Ichikawa, K., Imanishi, M., Rodríguez Espinosa, J. M., & Telesco, C. (2016). The complex evolutionary paths of local infrared bright galaxies: A high-angular resolution mid-infrared view. Monthly Notices of the Royal Astronomical Society, 463(3), 2405-2424. https://doi.org/10.1093/mnras/stw2031