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arXiv · 2302.05232

A Dwarf Galaxy Debris Stream Associated with Palomar 1 and the Anticenter Stream

Yong Yang·Jing-Kun Zhao·Xian-Hao Ye·Gang Zhao·Ke-Feng Tan
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Abstract

We report the discovery of a new stream (dubbed as Yangtze) detected in $Gaia$ Data Release 3. The stream is at a heliocentric distance of $\sim$ 9.12 kpc and spans nearly 27$\deg$ by 1.9$\deg$ on sky. The colour-magnitude diagram of Yangtze indicates a stellar population of Age $\sim$ 11 Gyr and [M/H] $\sim$ -0.7 dex. It has a number density of about 5.5 stars degree$^{-2}$ along with a surface brightness of $\Sigma_G \simeq$ 34.9 mag arcsec$^{-2}$. The dynamics and metallicity estimate suggest that Yangtze may be closely related to Palomar 1 and the Anticenter stream.

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Yong Yang, Jing-Kun Zhao, Xian-Hao Ye, Gang Zhao, Ke-Feng Tan. 2023-02-10. A Dwarf Galaxy Debris Stream Associated with Palomar 1 and the Anticenter Stream. https://doi.org/10.3847/2041-8213%2Facbb5c

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