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A kinematically decoupled component in NGC4778

M. Spavone·E. Iodice·G. Longo·M. Paolillo
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Abstract

We present a kinematical and photometrical study of a member, NGC4778, of the nearest (z=0.0137) compact group: Hickson 62. Our analysis reveals that Hickson 62a, also known as NGC4778, is an S0 galaxy with kinematical and morphological peculiarities, both in its central regions (r < 5'') and in the outer halo. In the central regions, the rotation curve shows the existence of a kinematically decoupled stellar component, offset with respect to the photometric center. In the outer halo we find an asymmetric rotation curve and a velocity dispersion profile showing a rise on the SW side, in direction of the galaxy NGC4776.

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M. Spavone, E. Iodice, G. Longo, M. Paolillo. 2007-01-23. A kinematically decoupled component in NGC4778. https://arxiv.org/abs/astro-ph/0701646

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