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arXiv · 1412.2069

A low-luminosity type-1 QSO sample: II. Tracing circumnuclear star formation in HE 1029-1831 with SINFONI

Gerold Busch·Semir Smajić·Julia Scharwächter·Andreas Eckart·Mónica Valencia-S.·Lydia Moser·Bernd Husemann·Melanie Krips·Jens Zuther
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Abstract

Circumnuclear star formation and AGN feedback is believed to play a critical role in the context of galaxy evolution. The low-luminosity QSO (LLQSO) sample that contains 99 of the closest AGN with redshift z<=0.06 fills the gap between the local AGN population and high-redshift QSOs that is essential to understand the AGN evolution with redshift. In this paper, we present the results of near-infrared H+K-integral field spectroscopy of the inner kiloparsecs of the LLQSO HE 1029-1831 with SINFONI. Line maps show that ionized hydrogen gas is located in spiral arms within the stellar bar and in a circumnuclear ring. Line fluxes and diagnostic line ratios indicate recent or ongoing star formation in the circumnuclear region and the presence of young and intermediate-age stellar populations in the bulge. In particular, we find traces of an intense starburst in the circumnuclear region that has begun around 100 Myr ago but has declined to a fraction of the maximum intensity now. We estimate the dynamical bulge mass and find that the galaxy follows published M_BH-M_bulge relations. However, bulge-disk decomposition of the K-band image with BUDDA reveals that HE 1029-1831 does not follow the M_BH-L_bulge relations of inactive galaxies. We conclude that the deviation from M_BH-L_bulge relations of inactive galaxies in this source is rather caused by young stellar populations and not by an undermassive black hole.

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Gerold Busch, Semir Smajić, Julia Scharwächter, Andreas Eckart, Mónica Valencia-S., Lydia Moser, Bernd Husemann, Melanie Krips, Jens Zuther. 2014-12-05. A low-luminosity type-1 QSO sample: II. Tracing circumnuclear star formation in HE 1029-1831 with SINFONI. https://doi.org/10.1051/0004-6361%2F201425261

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