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arXiv · 1004.2464

In the Shadow of the Transiting Disk: Imaging epsilon Aurigae in Eclipse

Brian Kloppenborg·Robert Stencel·John D. Monnier·Gail Schaefer·Ming Zhao·Fabien Baron·Hal McAlister·Theo ten Brummelaar·Xiao Che·Chris Farrington·Ettore Pedretti·PJ Sallave-Goldfinger·Judit Sturmann·Laszlo Sturmann·Nathalie Thureau·Nils Turner·Sean M. Carroll
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Abstract

Eclipses of the single-line spectroscopic binary star, epsilon Aurigae, provide an opportunity to study the poorly-defined companion. We used the MIRC beam combiner on the CHARA array to create interferometric images during eclipse ingress. Our results demonstrate that the eclipsing body is a dark disk that is opaque and tilted, and therefore exclude alternative models for the system. These data constrain the geometry and masses of the components, providing evidence that the F-star is not a massive supergiant star.

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Brian Kloppenborg, Robert Stencel, John D. Monnier, Gail Schaefer, Ming Zhao, Fabien Baron, Hal McAlister, Theo ten Brummelaar, Xiao Che, Chris Farrington, Ettore Pedretti, PJ Sallave-Goldfinger, Judit Sturmann, Laszlo Sturmann, Nathalie Thureau, Nils Turner, Sean M. Carroll. 2010-04-14. In the Shadow of the Transiting Disk: Imaging epsilon Aurigae in Eclipse. https://doi.org/10.1038/nature08968

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