Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-29T18:52:36.572Z Has data issue: false hasContentIssue false
  • English
  • Français

10.5. Short-term variability of Sagittarius A∗ at millimeter wavelengths

Published online by Cambridge University Press:  25 May 2016

T. Tsutsumi ,
T. Kawabata ,
A. Miyazaki  and
M. Tsuboi
T. Tsutsumi
Affiliation:
Nobeyama Radio Observatory, NAOJ, Minamimaki, Minamisaku, Nagano 384-13, Japan
T. Kawabata
Affiliation:
Bisei Astronomical Observatory, Okayama, Japan
A. Miyazaki
Affiliation:
Institute of Astrophysics and Planetary Science, Ibaraki University, Ibaraki, Japan
M. Tsuboi
Affiliation:
Institute of Astrophysics and Planetary Science, Ibaraki University, Ibaraki, Japan

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Time variability of Sgr A∗ at cm wavelengths is well known phenomenon and has been studied by several authors (e.g. Lo 1989; Zhao et al. 1992). On the other hand, variability at millimeter wavelengths is not well established. Wright & Backer (1993) reported significant flux variations at λ = 3.4mm in a month during the decay of a flare observed by the Very Large Array in 1990. However others found no variability at millimeter and submillimeter wavelengths (Gwinn et al. 1991; Zylka et al. 1995). Emission from extended component surrounding Sgr A∗ is significant even at millimeter wavelengths (e.g. Tsuboi et al. 1988), thus it is important to observe with a narrower beam to isolate the compact component for accurate measurement of variability of Sgr A∗. Here we present some results from an on-going millimeter monitoring program of Sgr A∗ with the Nobeyama Millimeter Array (NMA).

Type
Part III. Black Holes and Central Activity
Information
Symposium - International Astronomical Union , Volume 184: The Central Regions of the Galaxy and Galaxies , 1998 , pp. 439 - 440
Copyright
Copyright © Kluwer 1998 

References

Beckert, T., Duschl, W. J., Mezger, P.G., and Zylka, R. 1996, A&A 307, 450.Google Scholar
Gwinn, C. R., et al. 1991, Ap. J. 381, L43.Google Scholar
Lo, K.Y. 1989 in The Center of the Galaxy, Morris, M. ed., 527.Google Scholar
Tsuboi, M., et al. 1988, PASJ 40, 665.Google Scholar
Tsutsumi, T., Kawabata, T., Miyazaki, A., and Tsuboi, M. 1997, in IAU Colloq.164 Radio Emission from Galactic and Extragalactic Compact Sources, Zensus, J. A., Wrobel, J.M., and Taylor, G. B. eds., in press.Google Scholar
Wright, M. C. H. and Backer, D. C. 1993, Ap. J 417, 560.Google Scholar
Zhao, J.-H., Goss, W. M., Lo, K.-Y., and Eker, R. D. 1992 in Relationships between active galactic nuclei and starburst galaxies, Filippenko, A. ed., 295.Google Scholar
Zylka, R., et al. 1995, A&A, 297, 83.Google Scholar