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arXiv · 1104.0363

Astrometry of Galactic Star-Forming Region G48.61+0.02 with VERA

Takumi Nagayama·Toshihiro Omodaka·Akiharu Nakagawa·Toshihiro Handa·Mareki Honma·Hideyuki Kobayashi·Noriyuki Kawaguchi·Yuji Ueno
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Abstract

We performed the astrometry of H2O masers in the Galactic star-forming region G48.61+0.02 with the VLBI Exploration of Radio Astrometry (VERA). We derived a trigonometric parallax of 199+/-7 micro as, which corresponds to a distance of 5.03+/-0.19 kpc. The distance to G48.61+0.02 is about a half of its far kinematic distance, which was often assumed previously. This distance places G48.61+0.02 in the Sagittarius-Carina arm and near the active star forming region and the supernova remnant W51. We also obtained the three dimensional motion of G48.61+0.02, and found that it has a large peculiar motion of 40+/-5 km/s. This peculiar motion would be originated with the multiple supernovae explosions in W51, or the streaming motion across the Sagittarius-Carina arm.

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Takumi Nagayama, Toshihiro Omodaka, Akiharu Nakagawa, Toshihiro Handa, Mareki Honma, Hideyuki Kobayashi, Noriyuki Kawaguchi, Yuji Ueno. 2011-04-05. Astrometry of Galactic Star-Forming Region G48.61+0.02 with VERA. https://doi.org/10.1093/pasj%2F63.4.719

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