Stellar Overdensity in the Local Arm in Gaia DR2

  title={Stellar Overdensity in the Local Arm in Gaia DR2},
  author={Yusuke Miyachi and Nobuyuki Sakai and Daisuke Kawata and Junichi Baba and Mareki Honma and Noriyuki Matsunaga and Kenta Fujisawa},
  journal={The Astrophysical Journal},
Using the cross-matched data of Gaia DR2 and 2MASS Point Source Catalog, we investigated the surface density distribution of stars aged ~1 Gyr in the thin disk in the range of 90° <= l <= 270°. We selected 4,654 stars above the turnoff corresponding to the age ~1 Gyr, that fall within a small box region in the color-magnitude diagram, (J-Ks)0 versus M(Ks), for which the distance and reddening are corrected. The selected sample shows an arm-like overdensity at 90° <= l <= 190°.This overdensity… 

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