A Gap in the Lower Main Sequence Revealed by Gaia Data Release 2

  title={A Gap in the Lower Main Sequence Revealed by
 Data Release 2},
  author={Wei Chun Jao and Todd J. Henry and Douglas R. Gies and Nigel C. Hambly},
  journal={The Astrophysical Journal},
We present the discovery of a gap near M G ≈ 10 in the main sequence on the Hertzsprung–Russell Diagram (HRD) based on measurements presented in Gaia Data Release 2 (DR2). Using an observational form of the HRD with M G representing luminosity and G BP − G RP representing temperature, the gap presents a diagonal feature that dips toward lower luminosities at redder colors. The gap is seen in samples extracted from DR2 with various distances, and is not unique to the Gaia photometry—it also… 
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