Microlensing binaries discovered through high-magnification channel
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Version 1 2023-05-17, 13:31Version 1 2023-05-17, 13:31
journal contribution
posted on 2025-01-15, 00:59authored byI-G Shin, J-Y Choi, S-Y Park, C Han, A Gould, T Sumi, A Udalski, Jean-Philippe BeaulieuJean-Philippe Beaulieu, M Dominik, W Allen, M Bos, GW Christie, DL Depoy, S Dong, J Drummond, A Gal-Yam, BS Gaudi, L-W Hung, J Janczak, S Kaspi, C-U Lee, F Mallia, D Maoz, A Maury, J McCormick, LAG Monard, D Moorhouse, JA Munoz, T Natusch, C Nelson, B-G Park, RW Pogge, D Polishook, Y Shvartzvald, A Shporer, G Thornley, JC Yee, F Abe, DP Bennett, IA Bond, CS Botzler, A Fukui, K Furusawa, F Hayashi, JB Hearnshaw, S Hosaka, Y Itow, K Kamiya, PM Kilmartin, S Kobara, A Korpela, W Lin, CH Ling, S Makita, K Masuda, Y Matsubara, N Miyake, Y Muraki, M Nagaya, K Nishimoto, K Ohnishi, T Okumura, K Omori, YC Perrott, N Rattenbury, T Saito, L Skuljan, DJ Sullivan, D Suzuki, WL Sweatman, PJ Tristram, K Wada, PCM Yock, MK Szymanski, M Kubiak, G Pietrzynski, I Soszynski, R Poleski, K Ulaczyk, L Wyrzykowski, S Kozlowski, P Pietrukowicz, MD Albrow, V Batista, DM Bramich, S Brillant, JAR Caldwell, JJ Calitz, A Cassan, Andrew ColeAndrew Cole, KH Cook, E Corrales, C Coutures, S Dieters, DD Prester, J Donatowicz, P Fouque, J Greenhill, M Hoffman, UG Jorgensen, SR Kane, D Kubas, J-B Marquette, R Martin, P Meintjes, J Menzies, KR Pollard, KC Sahu, J Wambsganss, A Williams, C Vinter, M Zub, A Allan, P Browne, K Horne, C Snodgrass, I Steele, R Street, Y Tsapras, KA Alsubai, V Bozza, MJ Burgdorf, SC Novati, P Dodds, S Dreizler, F Finet, T Gerner, M Glitrup, F Grundahl, S Hardis, K Harpsoe, FV Hessman, TC Hinse, M Hundertmark, N Kains, E Kerins, C Liebig, G Maier, L Mancini, M Mathiasen, MT Penny, S Proft, S Rahvar, D Ricci, G Scarpetta, S Schafer, F Schonebeck, J Skottfelt, J Surdej, J Southworth, F Zimmer
Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010. The perturbations, which are confined near the peak of the light curves, can be easily distinguished from the central perturbations caused by planets. However, the degeneracy between close and wide binary solutions cannot be resolved with a 3σ confidence level for three events, implying that the degeneracy would be an important obstacle in studying binary distributions. The dependence of the degeneracy on the lensing parameters is consistent with a theoretical prediction that the degeneracy becomes severe as the binary separation and the mass ratio deviate from the values of resonant caustics. The measured mass ratio of the event OGLE-2008-BLG-510/MOA-2008-BLG-369 is q ~ 0.1, making the companion of the lens a strong brown dwarf candidate.
History
Publication title
Astrophysical Journal
Volume
746
Issue
2
Article number
127
Number
127
Pagination
1-13
ISSN
0004-637X
Department/School
School of Natural Sciences, Physics
Publisher
Institute of Physics Publishing Ltd.
Publication status
Published
Place of publication
United States
Rights statement
Copyright 2012 The American Astronomical Society
Socio-economic Objectives
280120 Expanding knowledge in the physical sciences