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arXiv · 1705.05553

OGLE-2016-BLG-1469L: Microlensing Binary Composed of Brown Dwarfs

C. Han·A. Udalski·T. Sumi·A. Gould·M. D. Albrow·S. -J. Chung·Y. K. Jung·Y. -H. Ryu·I. -G. Shin·J. C. Yee·W. Zhu·S. -M. Cha·S. -L. Kim·D. -J. Kim·C. -U. Lee·Y. Lee·B. -G. Park·I. Soszyński·P. Mróz·P. Pietrukowicz·M. K. Szymański·J. Skowron R. Poleski·S. Kozłowski·K. Ulaczyk·M. Pawlak·F. Abe·Y. Asakura·D. P. Bennett·I. A. Bond·A. Bhattacharya·M. Donachie·M. Freeman·A. Fukui·Y. Hirao·Y. Itow·N. Koshimoto·M. C. A. Li·C. H. Ling·K. Masuda·Y. Matsubara·Y. Muraki·M. Nagakane·K. Ohnishi·H. Oyokawa·N. J. Rattenbury·To. Saito·A. Sharan·D. J. Sullivan·D. Suzuki·P. J. Tristram·T. Yamada·A. Yonehara·R. Barry
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Abstract

We report the discovery of a binary composed of two brown dwarfs, based on the analysis of the microlensing event OGLE-2016-BLG-1469. Thanks to detection of both finite-source and microlens-parallax effects, we are able to measure both the masses $M_1\sim 0.05\ M_\odot$, $M_2\sim 0.01\ M_\odot$, and distance $D_{\rm L} \sim 4.5$ kpc, as well as the projected separation $a_\perp \sim 0.33$ au. This is the third brown-dwarf binary detected using the microlensing method, demonstrating the usefulness of microlensing in detecting field brown-dwarf binaries with separations less than 1 au.

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C. Han, A. Udalski, T. Sumi, A. Gould, M. D. Albrow, S. -J. Chung, Y. K. Jung, Y. -H. Ryu, I. -G. Shin, J. C. Yee, W. Zhu, S. -M. Cha, S. -L. Kim, D. -J. Kim, C. -U. Lee, Y. Lee, B. -G. Park, I. Soszyński, P. Mróz, P. Pietrukowicz, M. K. Szymański, J. Skowron R. Poleski, S. Kozłowski, K. Ulaczyk, M. Pawlak, F. Abe, Y. Asakura, D. P. Bennett, I. A. Bond, A. Bhattacharya, M. Donachie, M. Freeman, A. Fukui, Y. Hirao, Y. Itow, N. Koshimoto, M. C. A. Li, C. H. Ling, K. Masuda, Y. Matsubara, Y. Muraki, M. Nagakane, K. Ohnishi, H. Oyokawa, N. J. Rattenbury, To. Saito, A. Sharan, D. J. Sullivan, D. Suzuki, P. J. Tristram, T. Yamada, A. Yonehara, R. Barry. 2017-05-16. OGLE-2016-BLG-1469L: Microlensing Binary Composed of Brown Dwarfs. https://doi.org/10.3847/1538-4357%2Faa740e

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