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VLBI Imaging and Astrometry of the RS CVn Binary Star IM Pegasi

Published online by Cambridge University Press:  13 May 2016

D.E. Lebach ,
M.I. Ratner ,
I.I. Shapiro ,
R.R. Ransom ,
N. Bartel ,
M.F. Bietenholz  and
J.-F. Lestrade
D.E. Lebach
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA
M.I. Ratner
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA
I.I. Shapiro
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA
R.R. Ransom
Affiliation:
Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, ON, M3J 1P3, Canada
N. Bartel
Affiliation:
Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, ON, M3J 1P3, Canada
M.F. Bietenholz
Affiliation:
Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, ON, M3J 1P3, Canada
J.-F. Lestrade
Affiliation:
Observatoire de Paris, Place Jules Janssen, Meudon Principal Cedex, F-92195, France

Abstract

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We have made 3.6 cm VLBI observations of the RS CVn binary star IM Pegasi (HR 8703) approximately four times per year since 1997 in support of the NASA/Stanford Relativity Gyroscope Experiment (Gravity Probe B). Phase-referenced maps reveal structural changes in the radio emission of the star on hour time scales during several of the sessions. Analyses of the VLBI phase delays with a Kalman-filter estimator reveal submilliarcsecond motions of the radio centroid of the star on hour and even subhour time scales. The observed structural changes and centroid motions often coincide with rapid changes in the star's flux density, as measured with the VLA. We report on our latest results and summarize our findings to date.

Type
Stars and Stellar Atmospheres
Information
Symposium - International Astronomical Union , Volume 205: Galaxies and their Constituents at the Highest Angular Resolutions , 2001 , pp. 318 - 321
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

Herring, T. A., Davis, J. L., & Shapiro, I. I. 1990, J. Geophys. Res., 95, 12,561.Google Scholar
Hjellming, R. M. 1988, in Galactic and Extra Galactic Radio Astronomy, eds. Verschuur, G. L. & Kellermann, K. I. (2nd ed.; New York: Springer-Verlag), 381.Google Scholar
Jones, K. L., Brown, A., Stewart, R. T., & Slee, O. B. 1996, MNRAS, 283, 1331.Google Scholar
Lebach, D. E., Ratner, M. I., Shapiro, I. I., Bartel, N., Bietenholz, M. F., Ransom, R. R., & Lestrade, J.-F. 1999, ApJ, 517, L43.Google Scholar
Lestrade, J.-F., et al. 1995, A&A, 304, 182.Google Scholar
Turneaure, J. P., Everitt, C. W. F., & Parkinson, B. W. 1986, in Proc. of the Fourth Marcel Grossmann Meeting on General Relativity, ed. Ruffini, R. (Amsterdam: Elsevier), 411.Google Scholar