Resolving the dynamical mass tension of the massive binary 9 Sagittarii
Resolving the dynamical mass tension of the massive binary 9 Sagittarii
Context. Direct dynamical mass measurements of stars with masses above 30 M ⊙ are rare. This is the result of the low yield of the upper initial mass function and the limited number of such systems in eclipsing binaries. Long-period, double-lined spectroscopic binaries that are also resolved astrometrically offer an …