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arXiv · 2208.05176

A New Cold Stream near the Southern Galactic Pole

Yong Yang·Jing-Kun Zhao·Xiang-Xiang Xue·Xian-Hao Ye·Gang Zhao
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Abstract

We report the discovery of a cold stream near the southern Galactic pole (dubbed as SGP-S) detected in $Gaia$ Early Data Release 3. The stream is at a heliocentric distance of $\sim$ 9.5 kpc and spans nearly 58$^\circ$ by 0.6$^\circ$ on sky. The colour-magnitude diagram of SGP-S indicates an old and metal-poor (age $\sim$ 12 Gyr, [M/H] $\sim$ -2.0 dex) stellar population. The stream's surface brightness reaches an exceedingly low level of $\Sigma_G \simeq$ 36.2 mag arcsec$^{-2}$. Neither extant globular clusters nor other known streams are associated with SGP-S.

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Yong Yang, Jing-Kun Zhao, Xiang-Xiang Xue, Xian-Hao Ye, Gang Zhao. 2022-08-10. A New Cold Stream near the Southern Galactic Pole. https://doi.org/10.3847/2041-8213%2Fac853c

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