Flux monitoring observations of Sgr A* at 8 GHz and 2 GHz with the NICT Kashima-Koganei VLBI system

S. Takekawa, Tomoharu Oka, M. Sekido

Research output: Contribution to journalArticle

Abstract

We have been conducting flux monitoring observations of Sgr A* at 8 GHz and 2 GHz using the NICT Kashima-Koganei VLBI system (109 km baseline) since mid-February 2013. The primary objective of the monitoring is a search for flux variation which is expected to be caused by the interaction between the G2 cloud and the accretion disk. Until 2013 September 22, we observed Sgr A* for 39 days, five hours on each day. Four quasars (NRAO 530, PKS 1622-253, PKS 1622-297, PKS 1921-293) were also observed as flux calibrators every 6 minutes. No significant change nor variation has been detected in the 8 GHz flux density of Sgr A*. The 8 GHz flux density was 0.81 ± 0.07 Jy (preliminary), while no significant 2 GHz emission was detected by our system. We will continue monitoring as often as possible until at least 2014 May.

Original languageEnglish
Pages (from-to)330-332
Number of pages3
JournalProceedings of the International Astronomical Union
Volume9
Issue numberS303
DOIs
Publication statusPublished - 2014

Fingerprint

very long base interferometry
very long baseline interferometry
monitoring
flux density
accretion disks
quasars
accretion
conduction
interactions

Keywords

  • Galaxy: center
  • Galaxy: nucleus
  • radio continuum: galaxies

ASJC Scopus subject areas

  • Astronomy and Astrophysics

Cite this

Flux monitoring observations of Sgr A* at 8 GHz and 2 GHz with the NICT Kashima-Koganei VLBI system. / Takekawa, S.; Oka, Tomoharu; Sekido, M.

In: Proceedings of the International Astronomical Union, Vol. 9, No. S303, 2014, p. 330-332.

Research output: Contribution to journalArticle

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