First Resolved Images of the Mira AB Symbiotic Binary at Centimeter Wavelengths

We report the first spatially resolved radio continuum measurements of the Mira AB symbiotic binary system, based on observations obtained with the Very Large Array (VLA). This is the first time that a symbiotic binary has been resolved unambiguously at centimeter wavelengths. We describe the results of VLA monitoring of both stars over a 10 month period, together with constraints on their individual spectral energy distributions, variability, and radio emission mechanisms. The emission from Mira A is consistent with originating from a radio photosphere, while the emission from Mira B appears best explained as free-free emission from an ionized circumstellar region ~(1-10) × 1013 cm in radius.

[1]  A. Taylor,et al.  Colliding Winds in Symbiotic Binary Systems. I. Analytic and Numerical Solutions , 2005 .

[2]  N. Soker,et al.  X-Rays from the Mira AB Binary System , 2004, astro-ph/0408329.

[3]  M. Karovska,et al.  Molecular Hydrogen Emission Lines in Far Ultraviolet Spectroscopic Explorer Observations of Mira B , 2003, astro-ph/0310105.

[4]  M. Karovska,et al.  Analysis of H2 Emission from Mira B in Ultraviolet Spectra from the Hubble Space Telescope , 2002 .

[5]  J. Peek,et al.  How Mira Variables Change Visual Light by a Thousandfold , 2001, astro-ph/0106571.

[6]  S. Dougherty,et al.  Non-thermal emission in Wolf-Rayet stars: are massive companions required? , 2000 .

[7]  S. Rappaport,et al.  Asymmetrical Planetary Nebulae II: From Origins to Microstructures , 2000 .

[8]  First Hubble Space Telescope Observations of Mira AB Wind-accreting Binary System , 1997 .

[9]  K. Menten,et al.  Radio Photospheres of Long-Period Variable Stars , 1997 .

[10]  U. Munari.  Symbiotic stars as precursors of the type Ia supernovae , 1992 .

[11]  M. Karovska,et al.  Asymmetries in the Atmosphere of Mira , 1991 .

[12]  A. Taylor,et al.  The collective radio properties of symbiotic stars , 1990 .

[13]  D. Osterbrock,et al.  Astrophysics of Gaseous Nebulae and Active Galactic Nuclei , 1989 .

[14]  P. Bowers,et al.  Detection of H I emission in the circumstellar envelope of Omicron Ceti (Mira) , 1988 .

[15]  A. Cassatella,et al.  The ultraviolet spectrum of the companion of Mira (omicron Ceti) : observational evidence for a disk formed by wind accretion. , 1985 .

[16]  D. Helfand,et al.  X-rays from accretion of red giant winds , 1984 .

[17]  A. Taylor,et al.  Radio emission from symbiotic stars - A binary model , 1984 .

[18]  A. Taylor,et al.  A Radio Survey of Symbiotic Stars , 1984 .

[19]  M. Barlow,et al.  The Radio and Infrared Spectrum of Early-type Stars Undergoing Mass Loss , 1975 .