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

TL;DR

This paper presents the first direct spatial resolution of the stellar components in the CH Cygni binary system using speckle interferometry, confirming orbital parameters and revealing the orientation of jets relative to the orbit.

Contribution

First resolved bispectrum speckle interferometry of CH Cygni, providing direct measurements of component separation and orbital parameters.

Findings

Measured component separation of 42 mas consistent with spectroscopic data.

Derived total binary mass of approximately 3.7 solar masses.

Found that radio jets are not orthogonal to the orbital plane.

Abstract

We report the first resolved bispectrum speckle interferometry of the symbiotic binary CH Cyg. The measured component separation, $\rho=42 \pm 2$ mas, 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 $M_{\rm t}=M_{\rm g}+M_{\rm wd}=3.7^{+3.5}_{-1.7} \rm M_{\sun}$, which is in good agreement with the value $M_{\rm t}=2.7^{+1.2}_{-0.6} \rm M_{\sun}$ derived from the spectroscopic orbit solution for the red giant and evolutionary contraints. We also show that the radio jets and the bipolar outflow are not orthogonal to the orbital plane of the binary system.