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arXiv · 1403.3409

Discovery of a cold stellar stream in the ATLAS DR1 data

S. E. Koposov·M. Irwin·V. Belokurov·E. Gonzales-Solares·A. Kupcu Yoldas·J. Lewis·N. Metcalfe·T. Shanks
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Abstract

We report the discovery of a narrow stellar stream crossing the constellations of Sculptor and Fornax in the Southern celestial hemisphere. The portion of the stream detected in the Data Release 1 photometry of the ATLAS survey is at least 12 degrees long, while its width is $\approx$ 0.25 deg. The Color Magnitude Diagram of this halo sub-structure is consistent with a metal-poor [Fe/H] $\lesssim -1.4$ stellar population located at a heliocentric distance of 20 $\pm$ 2 kpc. There are three globular clusters that could tentatively be associated with the stream: NGC 7006, NGC 7078 (M15) and Pyxis, but NGC 7006 and 7078 seem to have proper motions incompatible with the stream orbit.

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S. E. Koposov, M. Irwin, V. Belokurov, E. Gonzales-Solares, A. Kupcu Yoldas, J. Lewis, N. Metcalfe, T. Shanks. 2014-03-13. Discovery of a cold stellar stream in the ATLAS DR1 data. https://doi.org/10.1093/mnrasl/slu060

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