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arXiv · 1512.05090

LAMOST 1: A Disrupted Satellite in the Constellation Draco

John J. Vickers·Martin C. Smith·Yonghui Hou·Yuefei Wang·Yong Zhang
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Abstract

Using LAMOST spectroscopic data, we find a strong signal of a comoving group of stars in the constellation of Draco. The group, observed near the apocenter of its orbit, is 2.6 kpc from the Sun with a metallicity of -0.64 dex. The system is observed as a streaming population of unknown provenance with mass of about 2.1E4 solar masses and an absolute V band magnitude of about -3.6. Its high metallicity, diffuse physical structure, and eccentric orbit may indicate that the progenitor satellite was a globular cluster rather than a dwarf galaxy or an open cluster.

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John J. Vickers, Martin C. Smith, Yonghui Hou, Yuefei Wang, Yong Zhang. 2015-12-16. LAMOST 1: A Disrupted Satellite in the Constellation Draco. https://doi.org/10.3847/2041-8205%2F816%2F1%2Fl2

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