A radial velocity survey of low Galactic latitude structures – II. The Monoceros Ring behind the Canis Major dwarf galaxy

An AAT/2dF Spectrograph Survey of low Galactic latitudes targeting the putative Canis Major dwarf galaxy and the (possibly) associated tidal debris of stars known as the Monoceros Ring, covering Galactic coordinates and , has revealed the presence of the Monoceros Ring in the background of the Canis Major dwarf galaxy. This detection resides at a Galactocentric distance of ∼18.9 ± 0.3 kpc (13.5 ± 0.3 kpc heliocentric), exhibiting a velocity of ∼132.8 ± 1.3 km s−1 with a dispersion of ∼22.7 ± 1.7 km s−1, both of these comparable to previous measurements of the Monoceros Ring in nearby fields. This detection highlights the increasing complexity of structure being revealed in recent surveys of the Milky Way thick disc and halo.

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