University Of Tasmania

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Interpretation of a short-term anomaly in the gravitational microlensing event MOA-2012-BLG-486

journal contribution
posted on 2023-05-17, 21:56 authored by Hwang, K-H, Choi, J-Y, Bond, IA, Sumi, T, Han, C, Gaudi, BS, Gould, A, Bozza, V, Beaulieu, J-P, Tsapras, Y, Abe, F, Bennett, DP, Botzler, CS, Chote, P, Freeman, M, Fukui, A, Fukunaga, D, Harris, P, Itow, Y, Koshimoto, N, Ling, CH, Masuda, K, Matsubara, Y, Muraki, Y, Namba, S, Ohnishi, K, Rattenbury, NJ, Saito, T, Sullivan, DJ, Sweatman, WL, Suzuki, D, Tristram, PJ, Wada, K, Yamai, N, Yock, PCM, Yonehara, A, Andrade de Almeida, L, DePoy, DL, Dong, S, Jablonski, F, Jung, YK, Kavka, A, Lee, C-U, Park, H, Pogge, RW, Shin, I-G, Yee, JC, Albrow, MD, Bachelet, E, Batista, V, Brillant, S, Caldwell, JAR, Cassan, A, Andrew ColeAndrew Cole, Corrales, E, Coutures, C, Dieters, S, Dominis Prester, D, Donatowicz, J, Fouque, P, Greenhill, J, Jorgensen, UG, Kane, SR, Kubas, D, Marquette, J-B, Martin, R, Meintjes, P, Menzies, J, Pollard, KR, Williams, A, Wouters, D, Bramich, DM, Dominik, M, Horne, K, Browne, P, Hundertmark, M, Ipatov, S, Kains, N, Snodgrass, C, Steele, IA, Street, RA
A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present the analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals.


Publication title

Astrophysical Journal



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School of Natural Sciences


IOP Publishing

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Copyright 2013 The American Astronomical Society

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Expanding knowledge in the physical sciences