OGLE-LMC-ECL-09937: The Most Massive Algol-Type Binary System With A Mass Measurement Accurate to 2%

TL;DR

This study analyzes the OGLE-LMC-ECL-09937 binary system, providing highly accurate mass and radius measurements for its components, making it the most massive known Algol-type system and valuable for stellar evolution research.

Contribution

It presents the most precise mass and radius measurements for a massive Algol-type binary, advancing understanding of high-mass stellar evolution and binary interactions.

Findings

Masses of primary and secondary are 21.04 and 7.61 solar masses.

System is the most massive Algol-type with <2% measurement accuracy.

Potential progenitor of a neutron star binary.

Abstract

This paper presents a detailed analysis of the light and radial velocity curves of the semi-detached eclipsing binary system OGLE-LMC-ECL-09937. The system is composed of a hot, massive and luminous primary star of a late-O spectral type, and a more evolved, but less massive and luminous secondary, implying an Algol-type system that underwent a mass transfer episode. We derive masses of 21.04 +/- 0.34 M_Sun and 7.61 +/- 0.09 M_Sun and radii of 9.93 +/- 0.06 R_Sun and 9.18 +/- 0.04 R_Sun, for the primary and the secondary component, respectively, which make it the most massive known Algol-type system with masses and radii of the components measured with <2% accuracy. Consequently, the parameters of OGLE-LMC-ECL-09937 provide an important contribution to the sparsely populated high-mass end of the stellar mass distribution, and an interesting object for stellar evolution studies, being a possible progenitor of a binary system composed of two neutron stars.