Orbital Solution & Fundamental Parameters of sigma Scorpii

TL;DR

This paper presents the first orbital solution for sigma Scorpii's spectroscopic pair using interferometry, providing refined fundamental parameters and a more accurate distance estimate, enhancing understanding of this beta Cephei variable system.

Contribution

It offers the first orbital solution for sigma Scorpii's spectroscopic pair and refines fundamental stellar parameters using interferometric measurements.

Findings

Orbital solution for sigma Scorpii's spectroscopic pair determined.

Refined distance estimate of 174 pc with improved accuracy.

Mass, radius, and magnitude of primary and secondary components derived.

Abstract

The first orbital solution for the spectroscopic pair in the multiple star system sigma Scorpii, determined from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. The primary component is of beta Cephei variable type and has been one of the most intensively studied examples of its class. The orbital solution, when combined with radial velocity results found in the literature, yields a distance of 174(+23,-18) pc, which is consistent with, but more accurate than the Hipparcos value. For the primary component we determine 18.4+/-5.4 M_sun, -4.12+/-0.34 mag and 12.7+/-1.8 R_sun for the mass, absolute visual magnitude and radius respectively. A B1 dwarf spectral type and luminosity class for the secondary is proposed from the mass determination of 11.9+/-3.1 M_sun and the estimated system age of 10 Myr.