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arXiv · 1101.1953

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

Alceste Z. Bonanos·Norberto Castro·Lucas M. Macri·Rolf-Peter Kudritzki
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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.

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Alceste Z. Bonanos, Norberto Castro, Lucas M. Macri, Rolf-Peter Kudritzki. 2011-02-08. The Distance to the Massive Eclipsing Binary LMC-SC1-105 in the Large Magellanic Cloud. https://doi.org/10.1088/2041-8205%2F729%2F1%2Fl9

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