Mapping the Milky Way with LAMOST– III. Complicated spatial structure in the outer disc

  title={Mapping the Milky Way with LAMOST– III. Complicated spatial structure in the outer disc},
  author={Haifeng Wang and Chao Liu and Yan Xu and Jun-chen Wan and Licai Deng},
  journal={Monthly Notices of the Royal Astronomical Society},
We present {complexity} of the Galactic outer disc {by fitting the stellar volume densities of the red giant branch stars with a two-disc component model}. {The discs are confirmed to} extend to $R\sim19$\,kpc. The radial density profile of the discs shows {two breaks at $R\sim11$ and $\sim14$\,kpc, respectively, which} separate the radial profile into three segments with different scale lengths of $2.12\pm0.26$, $1.18\pm0.08$, and $2.72$\,kpc at $R 14$\,kpc, respectively. The first {break} is… Expand
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