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arXiv · 1501.04107

Spitzer as Microlens Parallax Satellite: Mass and Distance Measurements of Binary Lens System OGLE-2014-BLG-1050L

Wei Zhu·A. Udalski·A. Gould·M. Dominik·V. Bozza·C. Han·J. C. Yee·S. Calchi Novati·C. A. Beichman·S. Carey·R. Poleski·J. Skowron·S. Kozlowski·P. Mroz·P. Pietrukowicz·G. Pietrzynski·M. K. Szymanski·I. Soszynski·K. Ulaczyk·L. Wyrzykowski·B. S. Gaudi·R. W. Pogge·D. L. DePoy·Y. K. Jung·J. -Y. Choi·K. -H. Hwang·I. -G. Shin·H. Park·J. Jeong
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Abstract

We report the first mass and distance measurement of a caustic-crossing binary system OGLE-2014-BLG-1050L using the space-based microlens parallax method. \emph{Spitzer} captured the second caustic-crossing of the event, which occurred $\sim$10 days before that seen from Earth. Due to the coincidence that the source-lens relative motion was almost parallel to the direction of the binary-lens axis, the four-fold degeneracy, which was known before only to occur in single-lens events, persists in this case, leading to either a lower-mass (0.2 $M_\odot$ and 0.07 $M_\odot$) binary at $\sim$1.1 kpc or a higher-mass (0.9 $M_\odot$ and 0.35 $M_\odot$) binary at $\sim$3.5 kpc. However, the latter solution is strongly preferred for reasons including blending and lensing probability. OGLE-2014-BLG-1050L demonstrates the power of microlens parallax in probing stellar and substellar binaries.

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Wei Zhu, A. Udalski, A. Gould, M. Dominik, V. Bozza, C. Han, J. C. Yee, S. Calchi Novati, C. A. Beichman, S. Carey, R. Poleski, J. Skowron, S. Kozlowski, P. Mroz, P. Pietrukowicz, G. Pietrzynski, M. K. Szymanski, I. Soszynski, K. Ulaczyk, L. Wyrzykowski, B. S. Gaudi, R. W. Pogge, D. L. DePoy, Y. K. Jung, J. -Y. Choi, K. -H. Hwang, I. -G. Shin, H. Park, J. Jeong. 2015-01-27. Spitzer as Microlens Parallax Satellite: Mass and Distance Measurements of Binary Lens System OGLE-2014-BLG-1050L. https://doi.org/10.1088/0004-637x%2F805%2F1%2F8

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