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The Korean Astronomical Society (한국천문학회)
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THE VLBI MONITORING PROJECT FOR 6.7 GHz METHANOL MASERS USING THE JVN/EAVN

  • SUGIYAMA, KOICHIRO (Center for Astronomy, Ibaraki University) ;
  • FUJISAWA, KENTA (The Research Institute for Time Studies, Yamaguchi University) ;
  • HACHISUKA, KAZUYA (Graduate school of Science and Engineering, Yamaguchi University) ;
  • YONEKURA, YOSHINORI (Center for Astronomy, Ibaraki University) ;
  • MOTOGI, KAZUHITO (The Research Institute for Time Studies, Yamaguchi University) ;
  • SAWADA-SATOH, SATOKO (Mizusawa VLBI Observatory) ;
  • MATSUMOTO, NAOKO (Mizusawa VLBI Observatory) ;
  • SAITO, YU (College of Science, Ibaraki University) ;
  • HIRANO, DAIKI (Graduate school of Science and Engineering, Yamaguchi University) ;
  • HAYASHI, KYONOSUKE (Graduate school of Science and Engineering, Yamaguchi University) ;
  • SHEN, ZHIQIANG (Key Laboratory of Radio Astronomy, Shanghai Astronomical Observatory, Chinese Academy of Sciences) ;
  • HONMA, MAREKI (Mizusawa VLBI Observatory) ;
  • HIROTA, TOMOYA (Mizusawa VLBI Observatory) ;
  • MURATA, YASUHIRO (The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • DOI, AKIHIRO (The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • NIINUMA, KOTARO (Graduate school of Science and Engineering, Yamaguchi University) ;
  • DODSON, RICHARD (International Center for Radio Astronomy Research, M468, The University of Western Australia) ;
  • RIOJA, MARIA (International Center for Radio Astronomy Research, M468, The University of Western Australia) ;
  • ELLINGSEN, SIMON (School of Mathematics and Physics, University of Tasmania) ;
  • CHEN, XI (Key Laboratory of Radio Astronomy, Shanghai Astronomical Observatory, Chinese Academy of Sciences) ;
  • KIM, KEE-TAE (Korea Astronomy and Space Science Institute) ;
  • OGAWA, HIDEO (Department of Physical Science, Osaka Prefecture University)
  • Received : 2014.11.30
  • Accepted : 2015.06.30
  • Published : 2015.09.30
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Abstract

We have initiated a Very Long Baseline Interferometer (VLBI) monitoring project of 36 methanol maser sources at 6.7 GHz using the Japanese VLBI Network (JVN) and East-Asian VLBI Network (EAVN), starting in August 2010. The purpose of this project is to systematically reveal 3-dimensional (3-D) kine-matics of rotating disks around forming high-mass protostars. As an initial result, we present proper mo- tion detections for two methanol maser sources showing an elliptical spatial morphology, G 002.53+00.19 and G 006.79-00.25, which could be the best candidates associated with the disk. The detected proper motions indicate a simple rotation in G 002.53+00.19 and rotation with expansion in G 006.79-00.25, respectively, on the basis of disk model fits with rotating and expanding components. The expanding motions might be caused by the magnetic-centrifugal wind on the disk.

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References

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