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Sub-milliarcsecond Imaging of SgrA* and M87

T. P. Krichbaum·D. A. Graham·M. Bremer·W. Alef·A. Witzel·J. A. Zensus·A. Eckart
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Abstract

We present and discuss new result from mm-VLBI observations of M87 and SgrA*, using the Global mm-VLBI array (GMVA). New 3mm-VLBI images of the inner jet of M87 are presented, showing details with a spatial resolution down to 15 Schwarzschild radii. This resolution corresponds to a similar spatial resolution (in terms of R_s) obtained for Sgr A*. We discuss existing and new size determinations for this source provided by mm-VLBI at wavelengths of 3, 2, and 1.4 mm. With respect to the morphological difference between Sgr A* and M87 (the latter exhibits a long jet), a comparison of the sub-milliarcsecond structures seen with mm-VLBI may lead to a better understanding of the astro-physical processes acting in the vicinity of super-massive black holes.

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T. P. Krichbaum, D. A. Graham, M. Bremer, W. Alef, A. Witzel, J. A. Zensus, A. Eckart. 2006-07-05. Sub-milliarcsecond Imaging of SgrA* and M87. https://doi.org/10.1088/1742-6596%2F54%2F1%2F052

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