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arXiv · 1311.5852

Long-term monitoring of Sgr A* at 7 mm with VERA and KaVA

Kazunori Akiyama·Motoki Kino·Bong Won Sohn·Sang Sung Lee·Sascha Trippe·Mareki Honma
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Abstract

We present the results of radio monitoring observations of Sgr A* at 7 mm (i.e. 43 GHz) with VLBI Exploration of Radio Astrometry (VERA), which is a VLBI array in Japan. VERA provides angular resolutions on millisecond scales, resolving structure within ~100 Schwarzschild radii of Sgr A* similar to Very Large Baseline Array (VLBA). We performed multi-epoch observations of Sgr A* in 2005 - 2008, and started monitoring it again with VERA from January 2013 for tracing the current G2 encounter event. Our preliminary results in 2013 show that Sgr A* on mas scales has been in ordinary state as of August 2013, although some fraction of the G2 cloud already passed pericenter of Sgr A* in April 2013. We will continue on monitoring Sgr A* with VERA and newly developed KaVA (KVN and VERA Array).

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Kazunori Akiyama, Motoki Kino, Bong Won Sohn, Sang Sung Lee, Sascha Trippe, Mareki Honma. 2013-11-22. Long-term monitoring of Sgr A* at 7 mm with VERA and KaVA. https://doi.org/10.1017/s1743921314000751

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