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arXiv · astro-ph/0007135

The Optical Velocity of the Antlia Dwarf Galaxy

Eline Tolstoy·Michael Irwin
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Abstract

We present the results of a VLT observing program carried out in service mode using FORS1 on ANTU in Long Slit mode to determine the optical velocities of nearby low surface brightness galaxies. Outlying Local Group galaxies are of paramount importance in placing constraints the dynamics and thus on both the age and the total mass of the Local Group. Optical velocities are also necessary to determine if the observations of HI gas in and around these systems are the result of gas associated with these galaxies or a chance superposition with high velocity HI clouds or the Magellanic Stream. The data were of sufficient signal-to-noise to obtain a reliable result in one of the galaxies we observed - Antlia - for which we have found an optical helio-centric radial velocity of 351 $\pm$ 15 km/s.

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Eline Tolstoy, Michael Irwin. 2000-07-11. The Optical Velocity of the Antlia Dwarf Galaxy. https://doi.org/10.1046/j.1365-8711.2000.03849.x

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