First spatial resolution of the stellar components of the interacting binary CH Cygni

We report the first resolved bispectrum speckle interferometry of the symbiotic binary CH Cyg. The measured component separation, ρ = 42 +/- 2mas, is consistent with the one derived from the known spectroscopic orbit and distance. In particular, our result implies a total mass of the binary of M_t = M_g + M_wd = 3.7^+3.5_-1.7M_solar, which is in good agreement with the value M_t = 2.7^+1.2_-0.6M_solar derived from the spectroscopic orbit solution for the red giant and evolutionary constraints. We also show that the radio jets and the bipolar outflow are not orthogonal to the orbital plane of the binary system.

Based on observations made with the 6-m BTA telescope, which is operated by the Special Astrophysical Observatory (SAO), Russia.

E-mail: mikolaj@camk.edu.pl