The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance

  title={The spiral structure of the Galaxy revealed by CS sources and evidence for the 4:1 resonance},
  author={Jacques R. D. L{\'e}pine and Alexandre Roman-Lopes and Zulema Abraham and Thiago C. Junqueira and Yu. N. Mishurov},
  journal={Monthly Notices of the Royal Astronomical Society},
We present a map of the spiral structure of the Galaxy, as traced by molecular carbon monosulphide (CS) emission associated with IRAS sources which are believed to be compact H ii regions. The CS line velocities are used to determine the kinematic distances of the sources in order to investigate their distribution in the galactic plane. This allows us to use 870 objects to trace the arms, a number larger than that of previous studies based on classical H ii regions. The distance ambiguity of… 

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