Interpretation of a short-term anomaly in the gravitational microlensing event MOA-2012-BLG-486
Version 2 2025-01-15, 00:59Version 2 2025-01-15, 00:59
Version 1 2023-05-17, 21:56Version 1 2023-05-17, 21:56
journal contribution
posted on 2025-01-15, 00:59authored byK-H Hwang, J-Y Choi, IA Bond, T Sumi, C Han, BS Gaudi, A Gould, V Bozza, Jean-Philippe BeaulieuJean-Philippe Beaulieu, Y Tsapras, F Abe, DP Bennett, CS Botzler, P Chote, M Freeman, A Fukui, D Fukunaga, P Harris, Y Itow, N Koshimoto, CH Ling, K Masuda, Y Matsubara, Y Muraki, S Namba, K Ohnishi, NJ Rattenbury, T Saito, DJ Sullivan, WL Sweatman, D Suzuki, PJ Tristram, K Wada, N Yamai, PCM Yock, A Yonehara, L Andrade de Almeida, DL DePoy, S Dong, F Jablonski, YK Jung, A Kavka, C-U Lee, H Park, RW Pogge, I-G Shin, JC Yee, MD Albrow, E Bachelet, V Batista, S Brillant, JAR Caldwell, A Cassan, Andrew ColeAndrew Cole, E Corrales, C Coutures, S Dieters, D Dominis Prester, J Donatowicz, P Fouque, J Greenhill, UG Jorgensen, SR Kane, D Kubas, J-B Marquette, R Martin, P Meintjes, J Menzies, KR Pollard, A Williams, D Wouters, DM Bramich, M Dominik, K Horne, P Browne, M Hundertmark, S Ipatov, N Kains, C Snodgrass, IA Steele, RA Street
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.
History
Publication title
Astrophysical Journal
Volume
778
Issue
1
Article number
55
Number
55
Pagination
1-6
ISSN
0004-637X
Department/School
School of Natural Sciences, Physics
Publisher
IOP Publishing
Publication status
Published
Place of publication
190 N. Independence Mall West, Suite 601, Phil.
Rights statement
Copyright 2013 The American Astronomical Society
Socio-economic Objectives
280120 Expanding knowledge in the physical sciences