2024RNAAS...8..101W

Sigma Sculptoris is a nearby star that was suspected of being a rotating Ap variable. It was recently found not to be an Ap star but rather a 47 days single-lined spectroscopic binary. Here we report on the direct detection of the companion with a K band flux ratio of 5.5% at a projected separation of 5.16 mas based on a VLTI/GRAVITY observation. We estimate isochrone masses M_A = 1.95M_⊙ and M_B = 0.72M_⊙, a semimajor axis a = 0.35 au and an orbital inclination i = 27° (or 153°). The large rotational velocity of the primary (assuming spin-orbit alignment) is consistent with the lack of prominent chemical peculiarities.