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 M1∼0.05M⊙, M2∼0.01M⊙, and distance DL∼4.5 kpc, as well as the projected separation a⊥∼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.
@article{arxiv.1705.05553,
title = {OGLE-2016-BLG-1469L: Microlensing Binary Composed of Brown Dwarfs},
author = {C. Han and A. Udalski and T. Sumi and A. Gould and M. D. Albrow and S. -J. Chung and Y. K. Jung and Y. -H. Ryu and I. -G. Shin and J. C. Yee and W. Zhu and S. -M. Cha and S. -L. Kim and D. -J. Kim and C. -U. Lee and Y. Lee and B. -G. Park and I. Soszyński and P. Mróz and P. Pietrukowicz and M. K. Szymański and J. Skowron R. Poleski and S. Kozłowski and K. Ulaczyk and M. Pawlak and F. Abe and Y. Asakura and D. P. Bennett and I. A. Bond and A. Bhattacharya and M. Donachie and M. Freeman and A. Fukui and Y. Hirao and Y. Itow and N. Koshimoto and M. C. A. Li and C. H. Ling and K. Masuda and Y. Matsubara and Y. Muraki and M. Nagakane and K. Ohnishi and H. Oyokawa and N. J. Rattenbury and To. Saito and A. Sharan and D. J. Sullivan and D. Suzuki and P. J. Tristram and T. Yamada and T. Yamada and A. Yonehara and R. Barry},
journal= {arXiv preprint arXiv:1705.05553},
year = {2017}
}