The first planetary microlensing event with two microlensed source stars
View/ Open
Date
03/2018Author
Metadata
Show full item recordAltmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
We present the analysis of the microlensing event MOA-2010-BLG-117, and show that the light curve can only be explained by the gravitational lensing of a binary source star system by a star with a Jupiter-mass ratio planet. It was necessary to modify standard microlensing modeling methods to find the correct light curve solution for this binary source, binary-lens event. We are able to measure a strong microlensing parallax signal, which yields the masses of the host star, M * = 0.58 ± 0.11 M ⊙, and planet, mp = 0.54 ± 0.10MJup, at a projected star–planet separation of a ⊥ = 2.42 ± 0.26 au, corresponding to a semimajor axis of a = 2.9 (^+1.6_-0.6) au. Thus, the system resembles a half-scale model of the Sun–Jupiter system with a half-Jupiter0mass planet orbiting a half-solar-mass star at very roughly half of Jupiter's orbital distance from the Sun. The source stars are slightly evolved, and by requiring them to lie on the same isochrone, we can constrain the source to lie in the near side of the bulge at a distance of DS = 6.9 ± 0.7 kpc, which implies a distance to the planetary lens system of DL = 3.5 ± 0.4 kpc. The ability to model unusual planetary microlensing events, like this one, will be necessary to extract precise statistical information from the planned large exoplanet microlensing surveys, such as the WFIRST microlensing survey.
Citation
Bennett , D P , Udalski , A , Han , C , Bond , I A , Beaulieu , J -P , Skowron , J , Gaudi , B S , Koshimoto , N , Abe , F , Asakura , Y , Barry , R K , Bhattacharya , A , Donachie , M , Evans , P , Fukui , A , Hirao , Y , Itow , Y , Li , M C A , Ling , C H , Masuda , K , Matsubara , Y , Muraki , Y , Nagakane , M , Ohnishi , K , Oyokawa , H , Ranc , C , Rattenbury , N J , Rosenthal , M K , Saito , T , Sharan , A , Sullivan , D J , Sumi , T , Suzuki , D , Tristram , P J , Yonehara , A , Szymański , M K , Poleski , R , Soszyński , I , Ulaczyk , K , Wyrzykowski , Ł , DePoy , D , Gould , A , Pogge , R W , Yee , J C , Albrow , M D , Bachelet , E , Batista , V , Bowens-Rubin , R , Brillant , S , Caldwell , J A R , Cole , A , Coutures , C , Dieters , S , Prester , D D , Donatowicz , J , Fouquė , P , Horne , K , Hundertmark , M , Kains , N , Kane , S R , Marquette , J -B , Menzies , J , Pollard , K R , Ranc , C , Sahu , K C , Wambsganss , J , Williams , A & Zub , M 2018 , ' The first planetary microlensing event with two microlensed source stars ' , Astronomical Journal , vol. 155 , no. 3 , 141 . https://doi.org/10.3847/1538-3881/aaadfa
Publication
Astronomical Journal
Status
Peer reviewed
ISSN
0004-6256Type
Journal article
Rights
© 2018, The American Astronomical Society. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/https://doi.org/10.3847/1538-3881/aaadfa
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.