Skip to main content Accessibility help
×
Home

VLBI astrometry toward Sgr D HII region with VERA

  • Daisuke Sakai (a1) (a2), Tomoaki Oyama (a2), Takumi Nagayama (a2), Mareki Honma (a2) (a3) (a4) and Hideyuki Kobayashi (a1) (a3)...

Abstract

The Galactic centre region shows outstanding non-circular motion unlike the Galactic disk. As scenarios describing this non-circular motion, resonance orbits formed by the Galactic bar potential or expanding motion by past activity of the central BH are proposed. However, these both scenarios are based on line-of-sight velocities of molecular clouds in this region, and such one-dimension velocity information is insufficient to separate these scenarios.

To reveal dynamics of the Galactic centre region, we conducted astromertic observations of 22 GHz water maser sources toward the Galactic centre direction. We conducted astrometric observations toward water maser source associated with Sgr D HII region. As a result, we succeeded to measure the parallax and proper motion of the maser source. The measured distance was 2.36(+0.58/-0.39) kpc. This result clearly indicates that this source is not associated with the Galactic centre, but located on the Galactic disk.

Copyright

References

Hide All
Downes, D. & Maxwell, A. 1966, ApJ, 146, 653
Güsten, R. 1989, The Center of the Galaxy, 136, 89
Lis, D. C. 1991, ApJL, 379, L53
Mehringer, D. M., Goss, W. M., Lis, D. C., Palmer, P., & Menten, K. M. 1998, ApJ, 493, 274
Sawada, M., Tsujimoto, M., Koyama, K., et al. 2009, PASJ, 61, 209
MathJax
MathJax is a JavaScript display engine for mathematics. For more information see http://www.mathjax.org.

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed