Open AccessOn the radio spectrum of CI Cygni: a test of popular models for symbiotic stars
Author(s) -
Mikołajewska J.,
Ivison R.J.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04379.x
Subject(s) - physics , astrophysics , stars , spectral energy distribution , symbiotic star , astronomy , binary number , ionization , wavelength , telescope , spectral line , emission spectrum , galaxy , optics , ion , arithmetic , mathematics , quantum mechanics
We have determined the spectral energy distribution at wavelengths between 6 cm and 850 μm for the prototypical S(stellar)‐type symbiotic star, CI Cygni, during quiescence. Data were obtained simultaneously with the Very Large Array and the SCUBA submillimetre (sub‐mm) camera on the James Clerk Maxwell Telescope. The data have allowed us to determine the free–free turnover frequency of the ionized component, facilitating a model‐dependent estimate of the binary separation to compare with the known orbital parameters of CI Cyg and to critically test the known models for radio emission from symbiotic stars. In particular, our data rule out the two most popular models: ionization of the giant wind by Lyman continuum photons from its hot companion, and emission resulting from the interaction of winds from the two binary components.