OGLE-2018-BLG-0022: First Prediction of an Astrometric Microlensing Signal from a Photometric Microlensing Event

May 2019 • 2019ApJ...876...81H

Authors • Han, Cheongho • Bond, Ian A. • Udalski, Andrzej • Gould, Andrew • Bozza, Valerio • Hirao, Yuki • Cassan, Arnaud • authors, Leading • Albrow, Michael D. • Chung, Sun-Ju • Hwang, Kyu-Ha • Lee, Chung-Uk • Ryu, Yoon-Hyun • Shin, In-Gu • Shvartzvald, Yossi • Yee, Jennifer C. • Jung, Youn Kil • Kim, Doeon • Kim, Woong-Tae • Cha, Sang-Mok • Kim, Dong-Jin • Kim, Hyoun-Woo • Kim, Seung-Lee • Lee, Dong-Joo • Lee, Yongseok • Park, Byeong-Gon • Pogge, Richard W. • Zang, Weicheng • KMTNet Collaboration • Abe, Fumio • Barry, Richard • Bennett, David P. • Bhattacharya, Aparna • Donachie, Martin • Fukui, Akihiko • Itow, Yoshitaka • Kawasaki, Kohei • Kondo, Iona • Koshimoto, Naoki • Li, Man Cheung Alex • Matsubara, Yutaka • Muraki, Yasushi • Miyazaki, Shota • Nagakane, Masayuki • Ranc, Clément • Rattenbury, Nicholas J. • Suematsu, Haruno • Sullivan, Denis J. • Sumi, Takahiro • Suzuki, Daisuke • Tristram, Paul J. • Yonehara, Atsunori • MOA Collaboration • Mróz, Przemek • Szymański, Michał K. • Skowron, Jan • Poleski, Radek • Soszyński, Igor • Pietrukowicz, Paweł • Kozłowski, Szymon • Ulaczyk, Krzysztof • Rybicki, Krzysztof A. • Iwanek, Patryk • Wrona, Marcin • OGLE Collaboration • Beichman, Charles A. • Bryden, Geoffery • Carey, Sean • Gaudi, B. Scott • Henderson, Calen B. • Spitzer Microlensing Team

Abstract • In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with the high-quality photometry data from ground-based observations combined with the space-based Spitzer observations of this long timescale event enables us to uniquely determine the masses M ₁ = 0.40 ± 0.05 M _⊙ and M ₂ = 0.13 ± 0.01 M _⊙ of the individual lens components. Because the lens-source relative parallax and the vector lens-source relative proper motion are unambiguously determined, we can likewise unambiguously predict the astrometric offset between the light centroid of the magnified images (as observed by the Gaia satellite) and the true position of the source. This prediction can be tested when the individual-epoch Gaia astrometric measurements are released.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2019ApJ...876...81H
• PDF https://iopscience.iop.org/article/10.3847/1538-4357/ab1539/pdf
• PDF https://stacks.iop.org/0004-637X/876/81/pdf
• PREPRINT http://arxiv.org/abs/1904.00139
• DATA https://irsa.ipac.caltech.edu/bibdata/2019/H/2019ApJ...876...81H.html
• ELECTR https://doi.org/10.3847%2F1538-4357%2Fab1539