Bibcode
Spavone, M.; Iodice, E.; Calvi, R.; Bettoni, D.; Galletta, G.; Longo, G.; Mazzei, P.; Minervini, G.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 393, Issue 1, pp. 317-328.
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2
2009
Citations
11
Refereed citations
10
Description
In this paper, we present a detailed study of the peculiar early-type
galaxy NGC 1947. The main goal of this work is to constrain the
dynamical status and the formation history of NGC 1947 by comparing the
observed properties with the predictions derived from different galaxy
formation scenarios. To this aim, we derived the photometric and
kinematical properties of NGC 1947. Due to the presence of an extended
dust lane, which crosses the galaxy centre along the photometric minor
axis, we used near-infrared (NIR) images (J and K bands) to derive an
accurate analysis of the stellar light distribution. Optical images (in
the V and R bands) are used to derive the colour profiles and colour
maps to study the structure of the dust lane. The observed kinematics
confirm the presence of two components with decoupled angular momentum:
gas and dust rotate along the minor axis, while the rotation velocities
of the stars are observed along the major axis. The complex structure
observed in NGC 1947 supports the hypothesis that some kind of
interactions happened in the evolution of this object. We analysed two
alternatives: a merging process and an accretion event. We discussed how
the observed properties strongly suggest that the decoupled ring of gas
and dust has been accreted from outside.