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MOA-2016-BLG-227Lb: a massive planet characterized by combining light-curve analysis and Keck AO imaging


Koshimoto, N and Shvartzvald, Y and Bennett, DP and Penny, MT and Hundertmark, M and Bond, IA and Zang, WC and Henderson, CB and Suzuki, D and Rattenbury, NJ and Sumi, T and Abe, F and Asakura, Y and Bhattacharya, A and Donachie, M and Evans, P and Fukui, A and Hirao, Y and Itow, Y and Li, MCA and Ling, CH and Masuda, K and Matsubara, Y and Matsuo, T and Muraki, Y and Nagakane, M and Ohnishi, K and Ranc, C and Saito, T and Sharan, A and Shibai, H and Sullivan, DJ and Tristram, PJ and Yamada, T and Yamada, T and Yonehara, A and Gelino, CR and Beichman, C and Beaulieu, J-P and Marquette, JB and Batista, V and Friedmann, M and Hallakoun, N and Kaspi, S and Maoz, D and Bryden, G and Calchi Novati, S and Howell, SB and Wang, TS and Mao, S and Fouque, P and Korhonen, H and Jorgensen, UG and Street, R and Tsapras, Y and Dominik, M and Kerins, E and Cassan, A and Snodgrass, C and Bachelet, E and Bozza, V and Bramich, DM, MOA-2016-BLG-227Lb: a massive planet characterized by combining light-curve analysis and Keck AO imaging, The Astronomical Journal, 154, (1) Article 3. ISSN 0004-6256 (2017) [Refereed Article]


Copyright Statement

Copyright 2017 The American Astronomical Society. All rights reserved.

DOI: doi:10.3847/1538-3881/aa72e0


We report the discovery of a microlensing planet - MOA-2016-BLG-227Lb - with a large planet/host mass ratio of q ≃ 9 × 10−3. This event was located near the K2 Campaign 9 field that was observed by a large number of telescopes. As a result, the event was in the microlensing survey area of a number of these telescopes, and this enabled good coverage of the planetary light-curve signal. High angular resolution adaptive optics images from the Keck telescope reveal excess flux at the position of the source above the flux of the source star, as indicated by the light-curve model. This excess flux could be due to the lens star, but it could also be due to a companion to the source or lens star, or even an unrelated star. We consider all these possibilities in a Bayesian analysis in the context of a standard Galactic model. Our analysis indicates that it is unlikely that a large fraction of the excess flux comes from the lens, unless solar-type stars are much more likely to host planets of this mass ratio than lower mass stars. We recommend that a method similar to the one developed in this paper be used for other events with high angular resolution follow-up observations when the follow-up observations are insufficient to measure the lens–source relative proper motion.

Item Details

Item Type:Refereed Article
Keywords:micro gravitational lensing, planetary systems
Research Division:Physical Sciences
Research Group:Astronomical sciences
Research Field:Cosmology and extragalactic astronomy
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the physical sciences
UTAS Author:Beaulieu, J-P (Dr Jean-Philippe Beaulieu)
ID Code:125297
Year Published:2017
Web of Science® Times Cited:27
Deposited By:Mathematics and Physics
Deposited On:2018-04-12
Last Modified:2018-07-25
Downloads:84 View Download Statistics

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