High-mass binary stars are known to show an unexplained discrepancy between the dynamical masses of the individual components and those predicted by models .
In this work , we study Sigma Scorpii , a double-lined spectroscopic binary system consisting of two B-type stars residing in an eccentric orbit .
The more massive primary component is a \beta Cep-type pulsating variable star .
Our analysis is based on a time-series of some 1 000 high-resolution spectra collected with the coralie spectrograph in 2006 , 2007 , and 2008 .
We use two different approaches to determine the orbital parameters of the star ; the spectral disentangling technique is used to separate the spectral contributions of the individual components in the composite spectra .
The non-LTE based spectrum analysis of the disentangled spectra reveals two stars of similar spectral type and atmospheric chemical composition .
Combined with the orbital inclination angle estimate found in the literature , our orbital elements allow a mass estimate of 14.7 \pm 4.5 M _ { \odot } and 9.5 \pm 2.9 M _ { \odot } for the primary and secondary component , respectively .
The primary component is found to pulsate in three independent modes , of which two are identified as fundamental and second overtone radial modes , while the third is an l = 1 non-radial mode .
Seismic modelling of the pulsating component refines stellar parameters to 13.5 ^ { +0.5 } _ { -1.4 } M _ { \odot } and 8.7 ^ { +0.6 } _ { -1.2 } M _ { \odot } , and delivers radii of 8.95 ^ { +0.43 } _ { -0.66 } R _ { \odot } and 3.90 ^ { +0.58 } _ { -0.36 } R _ { \odot } for the primary and secondary , respectively .
The age of the system is estimated to be \sim 12 Myr .