The Distance to the Massive Eclipsing Binary LMC-SC1-105 in the Large Magellanic Cloud

TL;DR

This study measures the distance to the massive O-type eclipsing binary LMC-SC1-105 in the Large Magellanic Cloud, demonstrating the potential of such systems as reliable distance indicators for mapping the galaxy's structure.

Contribution

First distance measurement to an O-type eclipsing binary in the LMC, confirming their usefulness as independent distance indicators.

Findings

Distance to LMC-SC1-105 is 50.6±1.6 kpc.

Agreement with previous eclipsing binary distance measurements.

Highlights the potential of early-type EBs for mapping LMC's structure.

Abstract

This paper presents the first distance measurement to the massive, semi-detached, eclipsing binary LMC-SC1-105, located in the LH 81 association of the Large Magellanic Cloud (LMC). Previously determined parameters of the system are combined with new near-infrared photometry and a new temperature analysis to constrain the reddening toward the system, and determine a distance of 50.6+/-1.6 kpc (corresponding to a distance modulus of 18.52+/-0.07 mag), in agreement with previous eclipsing binary measurements. This is the sixth distance measurement to an eclipsing binary in the LMC, although the first to an O-type system. We thus demonstrate the suitability of O-type eclipsing binaries (EBs) as distance indicators. We suggest using bright, early-type EBs to measure distances along different sight lines, as an independent way to map the depth of the LMC and resolve the controversy about its three-dimensional structure.