A MOLECULAR SPIRAL ARM IN THE FAR OUTER GALAXY

@article{Dame2011AMS,
  title={A MOLECULAR SPIRAL ARM IN THE FAR OUTER GALAXY},
  author={Thomas M. Dame and Patrick Thaddeus},
  journal={The Astrophysical Journal Letters},
  year={2011},
  volume={734}
}
We have identified a spiral arm lying beyond the Outer Arm in the first Galactic quadrant ∼15 kpc from the Galactic center. After tracing the arm in existing 21 cm surveys, we searched for molecular gas using the CfA 1.2 m telescope and detected CO at 10 of 220 positions. The detections are distributed along the arm from l = 13°, v = −21 km s−1 to l = 55°, v = −84 km s−1 and coincide with most of the main H i concentrations. One of the detections was fully mapped to reveal a large molecular… 

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