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تسجيل مستخدم جديدOGLE-2016-BLG-1266: A Probable Brown-Dwarf/Planet Binary at the Deuterium Fusion Limit
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We report the discovery, via the microlensing method, of a new very-low-mass binary system. By combining measurements from Earth and from the Spitzer telescope in Earth-trailing orbit, we are able to measure the microlensing parallax of the event, and find that the lens likely consists of an $(12.0 pm 0.6) M_{rm J}$ + $(15.7 pm 1.5) M_{rm J}$ super-Jupiter / brown-dwarf pair. The binary is located at a distance of $(3.08 pm 0.18)$ kpc in the Galactic Plane, and the components have a projected separation of $(0.43 pm 0.03)$ AU. Two alternative solutions with much lower likelihoods are also discussed, an 8- and 6-$M_{rm J}$ model and a 90- and 70-$M_{rm J}$ model. Although disfavored at the 3-$sigma$ and 5-$sigma$ levels, these alternatives cannot be rejected entirely. We show how the more-massive of these models could be tested with future direct imaging.
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