| Title | OGLE-2012-BLG-0455/MOA-2012-BLG-206: MICROLENSING EVENT WITH AMBIGUITY IN PLANETARY INTERPRETATIONS CAUSED BY INCOMPLETE COVERAGE OF PLANETARY SIGNAL |
| Authors | Park, H. Han, C. Gould, A. Udalski, A. Sumi, T. Fouque, P. Choi, J.Y. Christie, G. Depoy, D. L. Dong, Subo Gaudi, B. S. Hwang, K.H. Jung, Y. K. Kavka, A. Lee, C.U. Monard, L. A. G. Natusch, T. Ngan, H. Pogge, R. W. Shin, I.G. Yee, J. C. Szymanski, M. K. Kubiak, M. Soszynski, I. Pietrzynski, G. Poleski, R. Ulaczyk, K. Pietrukowicz, P. Kozlowski, S. Skowron, J. Wyrzykowski, L. Abe, F. Bennett, D. P. Bond, I. A. Botzler, C. S. Chote, P. Freeman, M. Fukui, A. Fukunaga, D. Harris, P. Itow, Y. Koshimoto, N. Ling, |
| Affiliation | Chungbuk Natl Univ, Inst Astrophys, Dept Phys, Chongju 371763, South Korea. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ Warsaw Observ, PL-00478 Warsaw, Poland. Osaka Univ, Dept Earth & Space Sci, Osaka 5600043, Japan. Univ Toulouse, CNRS, IRAP, F-31400 Toulouse, France. Auckland Observ, Auckland, New Zealand. Texas A&M Univ, Dept Phys & Astron, College Stn, TX 77843 USA. Peking Univ, Kavli Inst Astron & Astrophys, Beijing 100871, Peoples R China. Korea Astron & Space Sci Inst, Taejon 305348, South Korea. Kleinkaroo Observ, Calitzdorp, South Africa. Bronberg Observ, Pretoria, South Africa. AUT Univ, Inst Radiophys & Space Res, Auckland, New Zealand. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Concepcion, Dept Astron, Concepcion, Chile. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Nagoya Univ, Solar Terr Environm Lab, Nagoya, Aichi 4648601, Japan. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Massey Univ, North Shore Mail Ctr, Inst Informat & Math Sci, Auckland, New Zealand. Univ Auckland, Dept Phys, Auckland 1001, New Zealand. Victoria Univ, Sch Chem & Phys Sci, Wellington, New Zealand. Natl Astron Observ Japan, Okayama Astrophys Observ, Asakuchi, Okayama 7190232, Japan. Nagano Natl Coll Technol, Nagano 3818550, Japan. Tokyo Metropolitan Coll Aeronaut, Tokyo 1168523, Japan. Mt John Univ Observ, Lake Tekapo 8770, New Zealand. Kyoto Sangyo Univ, Fac Sci, Dept Phys, Kyoto 6038555, Japan. |
| Keywords | gravitational lensing: micro planets and satellites: general GRAVITATIONAL BINARY-LENS DIFFERENCE IMAGE-ANALYSIS GALACTIC BULGE PHOTOMETRY SYSTEMS MASS PERTURBATIONS |
| Issue Date | 2014 |
| Publisher | astrophysical journal |
| Citation | ASTROPHYSICAL JOURNAL.2014,787,(1). |
| Abstract | Characterizing a microlensing planet is done by modeling an observed lensing light curve. In this process, it is often confronted that solutions of different lensing parameters result in similar light curves, causing difficulties in uniquely interpreting the lens system, and thus understanding the causes of different types of degeneracy is important. In this work, we show that incomplete coverage of a planetary perturbation can result in degenerate solutions even for events where the planetary signal is detected with a high level of statistical significance. We demonstrate the degeneracy for an actually observed event OGLE-2012-BLG-0455/MOA-2012-BLG-206. The peak of this high-magnification event (A(max) similar to 400) exhibits very strong deviation from a point-lens model with Delta chi(2) greater than or similar to 4000 for data sets with a total of 6963 measurements. From detailed modeling of the light curve, we find that the deviation can be explained by four distinct solutions, i.e., two very different sets of solutions, each with a twofold degeneracy. While the twofold (so-called close/wide) degeneracy is well understood, the degeneracy between the radically different solutions is not previously known. The model light curves of this degeneracy differ substantially in the parts that were not covered by observation, indicating that the degeneracy is caused by the incomplete coverage of the perturbation. It is expected that the frequency of the degeneracy introduced in this work will be greatly reduced with the improvement of the current lensing survey and follow-up experiments and the advent of new surveys. |
| URI | http://hdl.handle.net/20.500.11897/212515 |
| ISSN | 0004-637X |
| DOI | 10.1088/0004-637X/787/1/71 |
| Indexed | SCI(E) |
| Appears in Collections: | 科维理天文与天体物理研究所 |
