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
Description
Funding: UK STFC grant ST/M001296/1 (KH).Collections
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