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arXiv · 0705.1758

The supermassive black hole in NGC4486a detected with SINFONI at the VLT

N. Nowak·R. P. Saglia·J. Thomas·R. Bender·M. Pannella·K. Gebhardt·R. I. Davies
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Abstract

The near-infrared integral field spectrograph SINFONI at the ESO VLT opens a new window for the study of central supermassive black holes. With a near-IR spatial resolution similar to HST optical and the ability to penetrate dust it provides the possibility to explore the low-mass end of the M-sigma relation (sigma<120km/s) where so far very few black hole masses were measured with stellar dynamics. With SINFONI we observed the central region of the low-luminosity elliptical galaxy NGC4486a at a spatial resolution of ~0.1arcsec in the K band. The stellar kinematics was measured with a maximum penalised likelihood method considering the region around the CO absorption band heads. We determined a black hole mass of M_BH=1.25^{+0.75}_{-0.79} x 10^7 M_sun (90% C.L.) using the Schwarzschild orbit superposition method including the full 2-dimensional spatial information. This mass agrees with the predictions of the M-sigma relation, strengthening its validity at the lower sigma end.

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N. Nowak, R. P. Saglia, J. Thomas, R. Bender, M. Pannella, K. Gebhardt, R. I. Davies. 2007-05-12. The supermassive black hole in NGC4486a detected with SINFONI at the VLT. https://doi.org/10.1111/j.1365-2966.2007.11949.x

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