Detection of Intrinsic Source Structure at ~3 Schwarzschild Radii with Millimeter-VLBI Observations of SAGITTARIUS A*

  title={Detection of Intrinsic Source Structure at ~3 Schwarzschild Radii with Millimeter-VLBI Observations of SAGITTARIUS A*},
  author={Rusen S. Lu and Thomas P. Krichbaum and Alan L. Roy and Vincent L. Fish and Sheperd S. Doeleman and Michael D. Johnson and Kazunori Akiyama and Dimitrios Psaltis and Walter Alef and Keiichi Asada and Christopher Beaudoin and Alessandra Bertarini and Lindy Blackburn and Raymond Blundell and Geoffrey C. Bower and Christiaan D. Brinkerink and Avery E. Broderick and Roger J. Cappallo and Geoffrey B. Crew and Jason Dexter and Matt Dexter and Heino Falcke and Robert W. Freund and Per Friberg and Christopher H. Greer and Mark A. Gurwell and Paul T. P. Ho and Mareki Honma and Makoto Inoue and Junhan Kim and James W. Lamb and Michael Lindqvist and David Macmahon and Daniel P. Marrone and Iv'an Mart'i-Vidal and Karl M. Menten and James M. Moran and Neil M. Nagar and Richard Plambeck and Rurik A. Primiani and Alan E. E. Rogers and Eduardo Ros and Helge Rottmann and Jason SooHoo and Justin S. Spilker and Jordan M. Stone and Peter A. Strittmatter and Remo P. J. Tilanus and Michael Titus and Laura Vertatschitsch and Jan Wagner and Jonathan Weintroub and Melvyn Wright and Ken Young and J. Anton Zensus and Lucy M Ziurys},
  journal={The Astrophysical Journal},
We report results from very long baseline interferometric (VLBI) observations of the supermassive black hole in the Galactic center, Sgr A*, at 1.3 mm (230 GHz). The observations were performed in 2013 March using six VLBI stations in Hawaii, California, Arizona, and Chile. Compared to earlier observations, the addition of the APEX telescope in Chile almost doubles the longest baseline length in the array, provides additional uv coverage in the N-S direction, and leads to a spatial resolution… Expand

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