Structure of Sagittarius A* at 86 GHz using VLBI Closure Quantities

  title={Structure of Sagittarius A* at 86 GHz using VLBI Closure Quantities},
  author={Sheperd S. Doeleman and Z.-Q. Shen and Alan E. E. Rogers and Geoffrey C. Bower and Melvyn C. H. Wright and J. H. Zhao and Donald Charles Backer and Joseph W. Crowley and Robert W. Freund and Paul T. P. Ho and K. Y. Lo and David P. Woody},
  journal={The Astronomical Journal},
  pages={2610 - 2617}
At radio wavelengths, images of the compact radio source Sagittarius A* (Sgr A*) in the Galactic center are scatter broadened with a λ2 dependence due to an intervening ionized medium. We present VLBI observations of Sgr A* at 86 GHz using a six station array, including the VLBA antennas at Pie Town, Fort Davis, and Los Alamos, the 12 m antenna at Kitt Peak, and the millimeter arrays at Hat Creek and Owens Valley. To avoid systematic errors due to imperfect antenna calibration, the data were… 

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