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arXiv · 2110.08061

Tracing the Origin of Moving Groups. III. Detecting Moving Groups in The LAMOST DR7

Yong Yang·Jingkun Zhao·Jiajun Zhang·Xianhao Ye·Gang Zhao
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Abstract

We revisit the moving groups (MGs) in the solar neighborhood with a sample of 91969 nearby stars constructed from LAMOST DR7. Using the wavelet technique and Monte Carlo simulations, five MGs together with a new candidate located at $V \simeq$ -130 km s$^{-1}$ are detected simultaneously in $V-\sqrt{U^2+2V^2}$ space. Taking into account the other known MGs, we conclude that MGs in the Galactic disk are spaced by approximately 15 $\sim$ 25 km s$^{-1}$ along $V$ velocity. The origin of detected MGs is analysed through the distributions of [Fe/H]$-$[Mg/Fe] and ages. Our results support attributing the origin to the continuous resonant mechanisms probably induced by the bar or spiral arms of the Milky Way.

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Yong Yang, Jingkun Zhao, Jiajun Zhang, Xianhao Ye, Gang Zhao. 2021-10-15. Tracing the Origin of Moving Groups. III. Detecting Moving Groups in The LAMOST DR7. https://doi.org/10.3847/1538-4357/ac289e

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