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FU Orionis resolved by infrared long baseline interferometry at a 2-AU scale

F. Malbet·J. -P. Berger·M. M. Colavita·C. D. Koresko·C. Beichman·The PTI collaboration
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Abstract

We present the first infrared interferometric observations of a young stellar object with a spatial projected resolution better than 2 AU. The observations were obtained with the Palomar Testbed Interferometer. FU Ori exhibits a visibility of V^2 =0.72 +/- 0.07 for a 103 +/- 5 m projected baseline at lambda = 2.2 microns. The data are consistent on the spatial scale probed by PTI both with a binary system scenario (maximum magnitude difference of 2.7 +/- 0.5 mag and smallest separation of 0.35 +/- 0.05 AU) and a standard luminous accretion disk model (approx. accretion rate of 6e-5 Mo/yr) where the thermal emission dominates the stellar scattering, and inconsistent with a single stellar photosphere.

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F. Malbet, J. -P. Berger, M. M. Colavita, C. D. Koresko, C. Beichman, The PTI collaboration. 1998-08-28. FU Orionis resolved by infrared long baseline interferometry at a 2-AU scale. https://doi.org/10.1086/311688

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