An analysis of binary microlensing event OGLE-2015-BLG-0060
Abstract
We present the analysis of stellar binary microlensing event OGLE-2015-BLG-0060 based on observations obtained from 13 different telescopes. Intensive coverage of the anomalous parts of the light curve was achieved by automated follow-up observations from the robotic telescopes of the Las Cumbres Observatory. We show that, for the first time, all main features of an anomalous microlensing event are well covered by follow-up data, allowing us to estimate the physical parameters of the lens. The strong detection of second-order effects in the event light curve necessitates the inclusion of longer-baseline survey data in order to constrain the parallax vector. We find that the event was most likely caused by a stellar binary-lens with masses M⋆1=0.87±0.12M⊙ and M⋆2=0.77±0.11M⊙. The distance to the lensing system is 6.41 ± 0.14 kpc and the projected separation between the two components is 13.85 ± 0.16 au. Alternative interpretations are also considered.
Citation
Tsapras , Y , Cassan , A , Ranc , C , Bachelet , E , Street , R , Udalski , A , Hundertmark , M , Bozza , V , Beaulieu , J P , Marquette , J B , Euteneuer , E , Bramich , D M , Dominik , M , Figuera Jaimes , R , Horne , K , Mao , S , Menzies , J , Schmidt , R , Snodgrass , C , Steele , I A , Wambsganss , J , Mróz , P , Szymański , M K , Soszyński , I , Skowron , J , Pietrukowicz , P , Kozłowski , S , Poleski , R , Ulaczyk , K , Pawlak , M , Jørgensen , U G , Skottfelt , J , Popovas , A , Ciceri , S , Korhonen , H , Kuffmeier , M , Evans , D F , Peixinho , N , Hinse , T C , Burgdorf , M J , Southworth , J , Tronsgaard , R , Kerins , E , Andersen , M I , Rahvar , S , Wang , Y , Wertz , O , Rabus , M , Calchi Novati , S , D'Ago , G , Scarpetta , G , Mancini , L , Abe , F , Asakura , Y , Bennett , D P , Bhattacharya , A , Donachie , M , Evans , P , Fukui , A , Hirao , Y , Itow , Y , Kawasaki , K , Koshimoto , N , Li , M C A , Ling , C H , Masuda , K , Matsubara , Y , Muraki , Y , Miyazaki , S , Nagakane , M , Ohnishi , K , Rattenbury , N , Saito , T , Sharan , A , Shibai , H , Sullivan , D J , Sumi , T , Suzuki , D , Tristram , P J , Yamada , T & Yonehara , A 2019 , ' An analysis of binary microlensing event OGLE-2015-BLG-0060 ' Monthly Notices of the Royal Astronomical Society , vol. 487 , no. 4 , pp. 4603–4614 . https://doi.org/10.1093/mnras/stz1404
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
ISSN
0035-8711Type
Journal article
Rights
Copyright 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This work has been made available online in accordance with the publisher's policies. This is the final published version of the work, which was originally published at https://doi.org/10.1093/mnras/stz1404
Description
Funding: UK STFC grant ST/M001296/1 (KH).Collections
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