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arXiv · 1410.7678

Modeling Transiting Circumstellar Disks: Characterizing the Newly Discovered Eclipsing Disk System OGLE LMC-ECL-11893

Erin L. Scott·Eric E. Mamajek·Mark J. Pecaut·Alice C. Quillen·Fred Moolekamp·Cameron P. M. Bell
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Abstract

We investigate the nature of the unusual eclipsing star OGLE LMC-ECL-11893 (OGLE J05172127-6900558) in the Large Magellanic Cloud recently reported by Dong et al. 2014. The eclipse period for this star is 468 days, and the eclipses exhibit a minimum of ~1.4 mag, preceded by a plateau of ~0.8 mag. Spectra and optical/IR photometry are consistent with the eclipsed star being a lightly reddened B9III star of inferred age ~150 Myr and mass of ~4 solar masses. The disk appears to have an outer radius of ~0.2 AU with predicted temperatures of ~1100-1400 K. We model the eclipses as being due to either a transiting geometrically thin dust disk or gaseous accretion disk around a secondary object; the debris disk produces a better fit. We speculate on the origin of such a dense circumstellar dust disk structure orbiting a relatively old low-mass companion, and on the similarities of this system to the previously discovered EE Cep.

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Erin L. Scott, Eric E. Mamajek, Mark J. Pecaut, Alice C. Quillen, Fred Moolekamp, Cameron P. M. Bell. 2014-10-28. Modeling Transiting Circumstellar Disks: Characterizing the Newly Discovered Eclipsing Disk System OGLE LMC-ECL-11893. https://doi.org/10.1088/0004-637x%2F797%2F1%2F6

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