Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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THE EVOLUTIONARY STAGE OF H II REGION AND SPECTRAL TYPES OF MASSIVE STARS FROM KINEMATICS OF H2O MASERS IN W51 MAIN

  • Received : 2010.01.28
  • Accepted : 2010.03.30
  • Published : 2010.04.30
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Abstract

We report relative proper motion measurements of $H_{2}O$ masers in massive star-forming region W51 Main, based on data sets of VLBI observations for $H_{2}O$ masers at 22 GHz with Japanese VERA telescopes from 2003 to 2006. Data reductions and single-beam imaging analysis are to measure internal kinematics of maser spots and eventually to estimate the three-dimensional kinematics of $H_{2}O$ masers in W51 Main. Average space motions and proper motion measurements of $H_{2}O$ masers are given both graphical and in table formats. We find in this study that W51 Main appears to be associated with hyper-compact H II region with multiple massive proto-stars whose spectral types are of late O.

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References

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