2011•Monthly Notices of the Royal Astronomical SocietyOpen access
OGLE-2009-BLG-023/MOA-2009-BLG-028: characterization of a binary microlensing event based on survey data
Kyu‐Ha Hwang, Cheongho Han, Andrzej Udalski, T. Sumi, Andrew P. Gould, M. Jaroszyński, Marcin Kubiak, Michał K. Szymański, Grzegorz Pietrzyński, I. Soszyński, O. Szewczyk, Krzysztof Ulaczyk, Ł. Wyrzykowski, F. Abe, D. P. Bennett, I. A. Bond, C. S. Botzler, M. Freeman, Akihiko Fukui, K. Furusawa, J. B. Hearnshaw, Y. Itow, K. Kamiya, Pam M. Kilmartin, A. V. Korpela, W. Lin, C. H. Ling, Kento Masuda, Y. Matsubara, N. Miyake, Y. Muraki, K. Ohnishi, Y. C. Perrott, Nicholas James Rattenbury, To. Saito, T. Sako, D. J. Sullivan, Winston LeMay Sweatman, Paul . J. Tristram, P. C. M. Yock
Open full text 5 citations
Abstract
We report the result of the analysis of the light curve of a caustic-crossing binary-lens microlensing event OGLE-2009-BLG-023/MOA-2009-BLG-028. Even though the event was observed solely by survey experiments, we could uniquely determine the mass of the lens and distance to it by simultaneously measuring the Einstein radius and lens parallax. From this, we find that the lens system is composed of M-type dwarfs with masses $(0.50\pm 0.07) \ M_\odot$ and $(0.15\pm 0.02)\ M_\odot$ located in the Galactic disk with a distance of $\sim 1.8$ kpc toward the Galactic bulge direction. The event demonstrates that physical lens parameters of binary-lens events can be routinely determined from future high-cadence lensing surveys and thus microlensing can provide a new way to study Galactic binaries.
Open-access reader