Title: Anomalous peculiar motions of high-mass young stars in the Scutum spiral arm
Authors: Immer, K.; Li, J.; Quiroga-Nuñez, L. H.; Reid, M. J.; Zhang, B.; Moscadelli, L.; Rygl, K. L. J.
First Author’s Institution: Joint Institute for VLBI ERIC (Netherlands)
Status: Published in Astronomy & Astrophysics.
ADS: 2019A&A...632A.123I
We present trigonometric parallax and proper motion measurements toward 22 GHz water and 6.7 GHz methanol masers in 16 high-mass star-forming regions. These sources are all located in the Scutum spiral arm of the Milky Way.
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The observations were conducted as part of the Bar and Spiral Structure Legacy (BeSSeL) survey.
A combination of 14 sources from a forthcoming study and 14 sources from the literature, we now have a sample of 44 sources in the Scutum spiral arm, covering a Galactic longitude range from 0° to 33°. A group of 16 sources shows large peculiar motions of which 13 are oriented toward the inner Galaxy. A likely explanation for these high peculiar motions is the combined gravitational potential of the spiral arm and the Galactic bar.
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