Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-25T15:36:47.861Z Has data issue: false hasContentIssue false
  • English
  • Français

Radio and IR interferometry of SiO maser stars

Published online by Cambridge University Press:  24 July 2012

Markus Wittkowski ,
David A. Boboltz ,
Malcolm D. Gray ,
Elizabeth M. L. Humphreys ,
Iva Karovicova  and
Michael Scholz
Markus Wittkowski
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany
David A. Boboltz
Affiliation:
US Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420, USA
Malcolm D. Gray
Affiliation:
Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester M13 9PL, UK
Elizabeth M. L. Humphreys
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany
Iva Karovicova
Affiliation:
Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
Michael Scholz
Affiliation:
Zentrum für Astronomie der Universität Heidelberg (ZAH), Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney NSW 2006, Australia
Rights & Permissions [Opens in a new window]

Abstract

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.

Radio and infrared interferometry of SiO maser stars provide complementary information on the atmosphere and circumstellar environment at comparable spatial resolution. Here, we present the latest results on the atmospheric structure and the dust condensation region of AGB stars based on our recent infrared spectro-interferometric observations, which represent the environment of SiO masers. We discuss, as an example, new results from simultaneous VLTI and VLBA observations of the Mira variable AGB star R Cnc, including VLTI near- and mid-infrared interferometry, as well as VLBA observations of the SiO maser emission toward this source. We present preliminary results from a monitoring campaign of high-frequency SiO maser emission toward evolved stars obtained with the APEX telescope, which also serves as a precursor of ALMA images of the SiO emitting region. We speculate that large-scale long-period chaotic motion in the extended molecular atmosphere may be the physical reason for observed deviations from point symmetry of atmospheric molecular layers, and for the observed erratic variability of high-frequency SiO maser emission.

Keywords

masersradiative transferturbulencetechniques: interferometricstars: AGB and post-AGBstars: atmospheresstars: circumstellar matterstars: fundamental parametersstars: mass losssupergiants
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 8 , Symposium S287: Cosmic Masers - from OH to H0 , January 2012 , pp. 209 - 216
Copyright
Copyright © International Astronomical Union 2012

References

Blommaert, J. A. D. L., Groenewegen, M. A. T., Okumura, K., et al. 2006, A&A, 460, 555Google Scholar
Boboltz, D. A. & Wittkowski, M. 2005, ApJ, 618, 953CrossRefGoogle Scholar
De Marco, O. 2009, PASP, 121, 316CrossRefGoogle Scholar
Gray, M. D., Ivison, R., Yates, J., Humphreys, E., Hall, P., & Field, D., 1995, MNRAS, 277, L67Google Scholar
Gray, M. D., Humphreys, E. M. L., & Yates, J. A. 1999, MNRAS, 304, 906CrossRefGoogle Scholar
Gray, M. D., Wittkowski, M., Scholz, M., et al. 2009, MNRAS, 394, 51CrossRefGoogle Scholar
Höfner, S. 2008, A&A, 491, L1Google Scholar
Humphreys, E. M. L., Gray, M., Yates, J., Field, D., Bowen, G., & Diamond, P., 1996, MNRAS, 282, 1359CrossRefGoogle Scholar
Humphreys, E. M. L., Gray, M. D., Yates, J. A., & Field, D. 1997, MNRAS, 287, 663CrossRefGoogle Scholar
Icke, V., Frank, A., & Heske, A. 1992, A&A, 258, 341Google Scholar
Ireland, M. J., Scholz, M., & Wood, P. R. 2004a, MNRAS, 352, 318CrossRefGoogle Scholar
Ireland, M. J., Scholz, M.Tuthill, P. G., & Wood, P. R. 2004b, MNRAS, 355, 444CrossRefGoogle Scholar
Ireland, M. J., Scholz, M., & Wood, P. R. 2008, MNRAS, 391, 1994CrossRefGoogle Scholar
Ireland, M. J., Scholz, M., & Wood, P. R. 2011, MNRAS, 418, 114CrossRefGoogle Scholar
Karovicova, I., Wittkowski, M., Boboltz, D. A., et al. 2011, A&A, 532, A134Google Scholar
Karovicova, I., 2011, PhD thesis, University of NiceGoogle Scholar
Little-Marenin, I. R. & Little, S. J. 1990, AJ, 99, 1173CrossRefGoogle Scholar
Mattsson, L., Wahlin, L., & Höfner, S. 2010, A&A, 509, A14Google Scholar
Neufeld, D. A., González-Alfonso, E., & Melnick, G. J., et al. 2011, ApJL, 727, L28CrossRefGoogle Scholar
Ohnaka, K., Driebe, T., Weigelt, G., & Wittkowski, M. 2007, A&A, 466, 1099Google Scholar
Samus, N. N., Durlevich, O. V., et al. 2009, VizieR Online Data Catalog, 2025Google Scholar
Wachter, A., Schröder, K.-P., Winters, J., Arndt, T., & Sedlmayr, E. 2002, A&A, 384, 452Google Scholar
Whitelock, P., Feast, M. W., & van Leeuwen, F. 2009, MNRAS, 386, 313CrossRefGoogle Scholar
Wittkowski, M., Boboltz, D. A., Ohnaka, K., Driebe, T., & Scholz, M. 2007, A&A, 470, 191Google Scholar
Wittkowski, M., Boboltz, D. A., Driebe, T., et al. 2008, A&A, 479, L21Google Scholar
Wittkowski, M., Boboltz, D. A., Ireland, M., et al. 2011, A&A, 532, L7Google Scholar
Woitke, P. 2006, A&A, 452, 537Google Scholar