The Size, Shape, and Scattering of Sagittarius A* at 86 GHz: First VLBI with ALMA

  title={The Size, Shape, and Scattering of Sagittarius A* at 86 GHz: First VLBI with ALMA},
  author={Sara Issaoun and M. D. Johnson and Lindy Blackburn and Christiaan D. Brinkerink and Monika Mo'scibrodzka and Andrew A. Chael and Ciriaco Goddi and Iv'an Mart'i-Vidal and Jan Wagner and Sheperd S. Doeleman and Heino Falcke and Thomas P. Krichbaum and Kazunori Akiyama and Uwe Bach and Katherine L. Bouman and Geoffrey C. Bower and Avery E. Broderick and Ilje Cho and Geoffrey B. Crew and Jason Dexter and Vincent L. Fish and Roman Gold and J. L. G'omez and Kazuhiro Hada and Antonio Hern'andez-G'omez and Michael Janssen and Motoki Kino and Michael Kramer and Laurent Loinard and R. S. Lu and Sera B. Markoff and Daniel P. Marrone and Lynn D. Matthews and James M. Moran and C. M{\"u}ller and Freek Roelofs and Eduardo Ros and Helge Rottmann and S. S{\'a}nchez and Remo P. J. Tilanus and Pablo de Vicente and Maciek Wielgus and J. Anton Zensus and G.-Y. Zhao},
  journal={The Astrophysical Journal},
The Galactic center supermassive black hole Sagittarius A∗ (Sgr A∗) is one of the most promising targets to study the dynamics of black hole accretion and outflow via direct imaging with very long baseline interferometry (VLBI). At 3.5 mm (86 GHz), the emission from Sgr A∗ is resolvable with the Global Millimeter VLBI Array (GMVA). We present the first observations of Sgr A∗ with the phased Atacama Large Millimeter/submillimeter Array (ALMA) joining the GMVA. Our observations achieve an angular… Expand
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