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arXiv · 0803.3806

Central K-band kinematics and line strength maps of NGC 1399

M. Lyubenova·H. Kuntschner·D. R. Silva
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Abstract

In this paper we present for the first time high spatial resolution K-band maps of the central kinematical and near-infrared spectral properties of the giant cD galaxy in the Fornax cluster, NGC 1399. We confirm the presence of a central velocity dispersion dip within radius < 0.2" seen in previous long-slit studies. Our velocity dispersion maps give evidence for a non-symmetric structure in this central area by showing three sigma peaks to the north-east, south-east and west of the galaxy centre. Additionally we measure near-IR line strength indices at unprecedented spatial resolution in NGC 1399. The most important features we observe in our 2-dimensional line strength maps are drops in Na I and CO(2-0) line strength in the nuclear region of the galaxy, coinciding spatially with the drop in sigma. The observed line strength and velocity dispersion changes suggest a scenario where the centre of NGC 1399 harbours a dynamically cold subsystem with a distinct stellar population.

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M. Lyubenova, H. Kuntschner, D. R. Silva. 2008-03-26. Central K-band kinematics and line strength maps of NGC 1399. https://doi.org/10.1051/0004-6361:20079314

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