Masses of the components of SB2 binaries observed with Gaia. IV. Accurate SB2 orbits for 14 binaries, and masses of 3 binaries

TL;DR

This study presents precise orbital solutions and stellar masses for 14 SB2 binary systems using six years of spectroscopic data, combining radial velocities and interferometry, with some masses determined to better than 0.2% accuracy.

Contribution

It provides accurate orbital parameters and stellar masses for 14 SB2 binaries, demonstrating the effectiveness of combining high-resolution spectroscopy and Gaia astrometry for precise stellar characterization.

Findings

Minimum masses with ~1% accuracy for 28 stars.

Masses of three binaries determined with relative errors below 4%.

Constraints on initial He-abundance, age, and metallicity for two systems.

Abstract

The orbital motion of non-contact double-lined spectroscopic binaries (SB2), with periods of a few tens of days to several years, holds unique accurate informations on individual stellar masses, that only long-term monitoring can unlock. The combination of radial velocity measurements from high-resolution spectrographs and astrometric measurements from high-precision interferometers allows the derivation of SB2 components masses down to the percent precision. Since 2010, we observed a large sample of SB2 with the SOPHIE spectrograph at the Observatoire de Haute-Provence, aiming at the derivation of orbital elements with sufficient accuracy to obtain masses of components with relative errors as low as 1$\%$ when the astrometric measurements of the Gaia satellite will be taken into account. In this paper we present the results from six years of observations of 14 SB2 systems with periods ranging from 33 to 4185 days. Using the TODMOR algorithm we computed radial velocities from the spectra, and then derived the orbital elements of these binary systems. The minimum masses of the 28 stellar components are then obtained with a sample average accuracy of 1.0$\pm$0.2$\,\%$. Combining the radial velocities with existing interferometric measurements, we derived the masses of the primary and secondary components of HIP 61100, HIP 95995 and HIP 101382 with relative errors for components (A,B) of respectively (2.0, 1.7)$\,\%$, (3.7, 3.7)$\,\%$, and (0.2, 0.1)$\,\%$. Using the Cesam2k stellar evolution code, we could constrain the initial He-abundance, age and metallicity for HIP 61100 and HIP 95995.