OGLE-2015-BLG-0196: GROUND-BASED GRAVITATIONAL MICROLENS PARALLAX CONFIRMED BY SPACE-BASED OBSERVATION

Journal Article · Sun Jan 01 00:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/834/1/82· OSTI ID:22661429

Han, C. ^[1]; Udalski, A.; Szymański, M. K.; Soszyński, I.; Skowron, J.; Mróz, P.; Poleski, R.; Pietrukowicz, P.; Kozłowski, S.; Ulaczyk, K.; Pawlak, M. ^[2]; Gould, A.; Zhu, Wei; Fausnaugh, M.; Gaudi, B. S. ^[3]; Yee, J. C. ^[4]; Beichman, C. ^[5]; Novati, S. Calchi ^[6]; Carey, S. ^[7]; Bryden, C. ^[8] ; others, and

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1. Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)
2. Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland)
3. Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States)
4. Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)
5. NASA Exoplanet Science Institute, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States)
6. Dipartimento di Fisica “E. R. Caianiello,” Uńiversitá di Salerno, Via Giovanni Paolo II, I-84084 Fisciano (Italy)
7. Spitzer Science Center, MS 220-6, California Institute of Technology, Pasadena, CA (United States)
8. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109 (United States)

In this paper, we present an analysis of the binary gravitational microlensing event OGLE-2015-BLG-0196. The event lasted for almost a year, and the light curve exhibited significant deviations from the lensing model based on the rectilinear lens-source relative motion, enabling us to measure the microlens parallax. The ground-based microlens parallax is confirmed by the data obtained from space-based microlens observations using the Spitzer telescope. By additionally measuring the angular Einstein radius from the analysis of the resolved caustic crossing, the physical parameters of the lens are determined up to the twofold degeneracy, u {sub 0} < 0 and u {sub 0} > 0, solutions caused by the well-known “ecliptic” degeneracy. It is found that the binary lens is composed of two M dwarf stars with similar masses, M {sub 1} = 0.38 ± 0.04 M {sub ⊙} (0.50 ± 0.05 M {sub ⊙}) and M {sub 2} = 0.38 ± 0.04 M {sub ⊙} (0.55 ± 0.06 M {sub ⊙}), and the distance to the lens is D {sub L} = 2.77 ± 0.23 kpc (3.30 ± 0.29 kpc). Here the physical parameters outside and inside the parentheses are for the u {sub 0} < 0 and u {sub 0} > 0 solutions, respectively.

• OSTI ID: 22661429
• Journal Information: Astrophysical Journal, Vol. 834, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BINARY STARS
DIAGRAMS
DISTANCE
DWARF STARS
GRAVITATIONAL LENSES
MASS
MATHEMATICAL SOLUTIONS
SPACE
TELESCOPES
VISIBLE RADIATION