Long-term monitoring of Sgr A* at 7 mm with VERA and KaVA
Long-term monitoring of Sgr A* at 7 mm with VERA and KaVA
复制标题
使用 VERA 和 KaVA 在 7 毫米处长期监测 Sgr A*
DOI:
10.1017/s1743921314000751
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发表时间:
2014
期刊:
影响因子:
--
通讯作者:
M.
中科院分区:
文献类型:
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作者:
Akiyama;K. ; Kino;M. ; Sohn;B. ; Lee;S. ; Trippe;S. ; Honma;M.
We present the results of radio monitoring observations of Sgr A* at 7 mm (i.e. 43 GHz) with the VLBI Exploration of Radio Astrometry (VERA), which is a VLBI array in Japan. VERA provides angular resolution on millisecond scales, resolving structures within 100 Schwarzschild radii of Sgr A* , similar to the Very Large Baseline Array (VLBA). We performed multi-epoch observations of Sgr A* in 2005 - 2008, and started monitoring it again with VERA from 2013 January to trace the current G2 encounter event. Our preliminary results in 2013 show that Sgr A* on mas scales has been in an ordinary state as of August 2013, although some fraction of the G2 cloud already passed the pericenter of Sgr A* in April 2013. We will continue monitoring Sgr A* with VERA and the newly developed KaVA (KVN and VERA Array).