The Spectroscopic Orbits of Three Double-lined Eclipsing Binaries: I. BG Ind, IM Mon, RS Sgr

TL;DR

This paper provides precise spectroscopic orbit solutions for three double-lined eclipsing binaries, using high-resolution spectra to determine radial velocities and orbital parameters, revealing their different physical and evolutionary states.

Contribution

It presents the first precise orbital solutions for BG Ind, IM Mon, and RS Sgr, utilizing high-resolution spectra and advanced RV measurement techniques.

Findings

Mass ratios: 0.894, 0.606, 0.325 for the three systems

Negligible orbital eccentricities for all targets

Different physical and evolutionary statuses inferred

Abstract

We present the spectroscopic orbit solutions of three double-lines eclipsing binaries, BG Ind, IM Mon and RS Sgr. The first precise radial velocities (RVs) of the components were determined using high resolution echelle spectra obtained at Mt. John University Observatory in New Zealand. The RVs of the components of BG Ind and RS Sgr were measured using Gaussian fittings to the selected spectral lines, whereas two-dimensional cross-correlation technique was preferred to determine the RVs of IM Mon since it has relatively short orbital period among the other targets and so blending of the lines is more effective. For all systems, the Keplerian orbital solution was used during the analysis and also circular orbit was adopted because the eccentricities for all targets were found to be negligible. The first precise orbit analysis of these systems gives the mass ratios of the systems as 0.894, 0.606 and 0.325, respectively for BG Ind, IM Mon and RS Sgr. Comparison of the mass ratio values, orbital sizes and minimum masses of the components of the systems indicates that all systems should have different physical, dynamical and probable evolutionary status.