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arXiv · 0909.4312

Probing the stellar population of seyfert galaxies: a near infrared perspective

R. Riffel·M. G. Pastoriza·A. Rodriguez-Ardila·C. Bonatto
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Abstract

We employ IRTF SpeX NIR (0.8--2.4mu m) spectra to investigate the stellar population (SP), active galactic nuclei (AGN), featureless continuum (FC) and hot dust properties in 9 Sy1 and 15 Sy2 galaxies. Both the {\sc starlight} code and the hot dust as an additional base element were used for the first time in this spectral range. Our synthesis shows significant differences between Sy1 and Sy2 galaxies: the hot dust component is required to fit the K-band spectra of ~90% of the Sy1 galaxies, and only of ~25% of the Sy2; about 50% of the Sy2 galaxies require an FC component contribution >20%; this fraction increases to about 60% in the Sy1. In about 50% of the Sy2, the combined FC and young components contribute with more than 20%, while this occurs in 90% of the Sy1, suggesting recent star formation in the central region. The central few hundred parsecs of our galaxy sample contain a substantial fraction of intermediate-age SPs with a mean metallicity near solar. Our SP synthesis confirms that the 1.1microns CN band can be used as a tracer of intermediate-age stellar populations.

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R. Riffel, M. G. Pastoriza, A. Rodriguez-Ardila, C. Bonatto. 2009-09-23. Probing the stellar population of seyfert galaxies: a near infrared perspective. https://doi.org/10.1017/s1743921310002711

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