천문학논총 (Publications of The Korean Astronomical Society)

  • 제30권2호
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  • Pages.649-650
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  • 2015
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  • 1225-1534(pISSN)
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  • 2287-6936(eISSN)
한국천문학회 (The Korean Astronomical Society)
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22 GHz MONITORING OF SGR A* DURING THE G2 PERI-CENTER PASSING WITH THE JAPANESE VLBI NETWORK

  • KAMEYA, O. (National Astronomical Observatory of Japan) ;
  • TSUBOI, M. (ISAS/JAXA) ;
  • ASAKI, Y. (ISAS/JAXA) ;
  • YONEKURA, Y. (Ibaraki Univ.) ;
  • MIYAMOTO, Y. (Univ. of Tsukuba) ;
  • KANEKO, H. (Univ. of Tsukuba) ;
  • SETA, M. (Univ. of Tsukuba) ;
  • NAKAI, N. (Univ. of Tsukuba) ;
  • MIYOSHI, M. (National Astronomical Observatory of Japan) ;
  • TAKABA, H. (Gifu Univ.) ;
  • WAKAMATSU, K. (Gifu Univ.) ;
  • FUKUZAKI, Y. (GSI) ;
  • MORIMITSU, T. (Univ. of Tokyo) ;
  • SEKIDO, M. (NICT)
  • 투고 : 2014.11.30
  • 심사 : 2015.06.30
  • 발행 : 2015.09.30
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초록

We have been performing daily VLBI monitoring of the flux density of Sagittarius (Sgr) $A^{\ast}$ at 22 GHz from February 2013 to August 2014 using a sub-array of the Japanese VLBI Network (JVN). The purpose of this monitoring is to explore the flux density variability at daily time resolution for a period longer than one year with the G2 cloud approaching. The flux density of Sgr $A^{\ast}$ is basically stable during the observational period, though there are some small variations. The average and scattering range are consistent with the previously observed values. We have observed no strong flare of Sgr $A^{\ast}$ although it is near the expected peri-center passing.

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참고문헌

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