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arXiv · 1212.0349

Flaring up of the Compact Cloud G2 during the Close Encounter with Sgr A*

Takayuki R. Saitoh·Junichiro Makino·Yoshiharu Asaki·Junichi Baba·Shinya Komugi·Makoto Miyoshi·Tohru Nagao·Masaaki Takahashi·Takaaki Takeda·Masato Tsuboi·Ken-ichi Wakamatsu
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Abstract

A compact gas cloud G2 is predicted to reach the pericenter of its orbit around the super massive black hole (SMBH) of our galaxy, Sagittarius A* (Sgr A*). This event will give us a rare opportunity to observe the interaction between SMBH and gas around it. We report the result of the fully three-dimensional simulation of the evolution of G2 during the first pericenter passage. The strong tidal force by the SMBH stretches the cloud along its orbit, and compresses it strongly in the vertical direction, resulting in the heating up and flaring up of the cloud. The bolometric luminosity will reach the maximum of $\sim100 L_{\odot}$. This flare should be easily observed in the near infrared.

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Takayuki R. Saitoh, Junichiro Makino, Yoshiharu Asaki, Junichi Baba, Shinya Komugi, Makoto Miyoshi, Tohru Nagao, Masaaki Takahashi, Takaaki Takeda, Masato Tsuboi, Ken-ichi Wakamatsu. 2013-08-09. Flaring up of the Compact Cloud G2 during the Close Encounter with Sgr A*. https://doi.org/10.1093/pasj%2Fpst003

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