CCD photometry of variable stars in the Magellanic Clouds – VII. The eclipsing binaries MACHO05:36:48.7−69:17:00 in the LMC, and MOA J005018.4−723855 and J005623.5−722123 in the SMC

• Published in: Monthly notices of the Royal Astronomical Society Vol. 349; no. 3; pp. 833 - 840
• Main Authors: Bayne, G. P., Tobin, W., Pritchard, J. D., Pollard, K. R., Albrow, M. D.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 11.04.2004; Blackwell Science
• Subjects: binaries: eclipsing; Magellanic Clouds; stars: fundamental parameters; stars: individual: MACHO05:36:487−69:17:00; stars: individual: MOA J0050184−723855; stars: individual: MOA J0056235−722123; stars: individual: MACHO05:36:487−69:17:00; binaries: eclipsing; stars: fundamental parameters; Magellanic Clouds; stars: individual: MOA J0056235−722123; stars: individual: MOA J0050184−723855; Eclipsing binary stars; Light curves; Effective temperature; Orbits; Brightening; Mass transfer; Massive stars; Small Magellanic Cloud; CCD photometry; Roche lobe; Large Magellanic Cloud; Gravity
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1111/j.1365-2966.2004.07535.x

Using improved techniques, we have obtained CCD uVJIC photometry for three eclipsing binary stars in the Magellanic Clouds and made preliminary analyses of the light curves. MACHO*05:36:48.7−69:17:00 in the Large Magellanic Cloud (LMC) is a detached, eccentric system. Apsidal motion is detected with a period of 100 ± 5 yr. The radii of the component stars are less than a fifth of their orbital separation and their masses are plausibly ∼14 and ∼20 M⊙. Similar masses may also characterize the components of MOA J005018.4−723855 in the Small Magellanic Cloud (SMC), but here the more massive star is cooler, fills its Roche lobe, and is probably in an early stage of case A mass transfer. MOA J005623.5−722123 in the SMC is detached with a nearly edge-on orbit. The masses are plausibly ∼14 and ∼16 M⊙. Because of polar gravity brightening, the star occulted at the shallower eclipse may actually have the higher mean effective temperature by a marginal amount.