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arXiv · astro-ph/9806331

Extended stellar kinematics of elliptical galaxies in the Fornax cluster

Alister Graham·Matthew Colless·Giovanni Busarello·Simone Zaggia·G. Longo
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Abstract

We present extended stellar kinematics for a sample of 13 elliptical galaxies in the Fornax cluster. Major-axis velocity dispersion profiles (VDPs) and rotation curves (RCs) are given for 12 of the galaxies. A major feature of this data is the spatial extension: for 8 galaxies the data extends beyond 1 R_e, and for 5 it extends beyond 2 R_e. Compared to the previously available data, this corresponds to an increase in spatial coverage by a factor from 1 to 5. Five of the ellipticals in the sample turn out to be rotationally-supported systems, having positive rotation parameter log (V/sigma)*. One of these five, and another 3 galaxies from the remaining sample, display evidence for bar-like kinematics. The data indicate that the true number of `dynamically hot' stellar systems, is much lower than previously thought: of the Es in the present sample only 1/4 are confirmed as `pressure-supported' systems. The data reveal a host of individual peculiarities, like: wiggles, strong gradients, and asymmetries in the rotation curve and/or in the velocity dispersion profile, thus showing that the presence of kinematically distinct components and/or triaxiality is a common characteristic of this class of object.

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Alister Graham, Matthew Colless, Giovanni Busarello, Simone Zaggia, G. Longo. 1998-06-25. Extended stellar kinematics of elliptical galaxies in the Fornax cluster. https://doi.org/10.1051/aas%3A1998325

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