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arXiv · 1411.0746

No Microwave Flare of Sagittarius A* around the G2 Periastron Passing

Masato Tsuboi·Yoshiharu Asaki·Osamu Kameya·Yoshinori Yonekura·Yusuke Miyamoto·Hiroyuki Kaneko·Masumichi Seta·Naomasa Nakai·Hiroshi Takaba·Ken-ichi Wakamatsu·Makoto Miyoshi·Yoshihiro Fukuzaki·Kenta Uehara·Mamoru Sekido
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Abstract

In order to explore any change caused by the G2 cloud approaching, we have monitored the flux density of Sgr A* at 22 GHz from Feb. 2013 to Aug. 2014 with a sub-array of Japanese VLBI Network . The observation period included the expected periastron dates. The number of observation epochs was 283 days. We have observed no significant microwave enhancement of Sgr A* in the whole observation period. The average flux density in the period is $S=1.23+/-0.33$ Jy. The average is consistent with the usually observed flux density range of Sgr A* at 22 GHz.

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Masato Tsuboi, Yoshiharu Asaki, Osamu Kameya, Yoshinori Yonekura, Yusuke Miyamoto, Hiroyuki Kaneko, Masumichi Seta, Naomasa Nakai, Hiroshi Takaba, Ken-ichi Wakamatsu, Makoto Miyoshi, Yoshihiro Fukuzaki, Kenta Uehara, Mamoru Sekido. 2014-11-04. No Microwave Flare of Sagittarius A* around the G2 Periastron Passing. https://doi.org/10.1088/2041-8205/798/1/l6

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