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A Fast Bar in the Post-Interaction Galaxy NGC 1023

Victor P. Debattista·Enrico Maria Corsini·J. A. L. Aguerri
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Abstract

We measured the bar pattern speed, $\om$, of the SB0 galaxy NGC 1023 using the Tremaine-Weinberg (1984) method with stellar-absorption slit spectroscopy. The morphology and kinematics of the \hi gas outside NGC 1023 suggest it suffered a tidal interaction, sometime in the past, with one of its dwarf companions. At present, however, the optical disc is relaxed. If the disc had been stabilized by a massive dark matter halo and formed its bar in the interaction, then the bar would have to be slow. We found $\om = 5.0 \pm 1.8$ \kmsa, so that the bar ends near its co-rotation radius. It is therefore rotating rapidly and must have a maximum disc.

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Victor P. Debattista, Enrico Maria Corsini, J. A. L. Aguerri. 2001-12-12. A Fast Bar in the Post-Interaction Galaxy NGC 1023. https://doi.org/10.1046/j.1365-8711.2002.05269.x

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