OGLE-2015-BLG-1649Lb : a gas giant planet around a low-mass dwarf
MetadataShow full item record
Altmetrics Handle Statistics
Altmetrics DOI Statistics
We report the discovery of an exoplanet from the analysis of the gravitational microlensing event OGLE-2015-BLG-1649 that challenges the core accretion model of planet formation and appears to support the disk instability model. The planet/host-star mass ratio is q = 7.2 × 10−3 and the projected separation normalized to the angular Einstein radius is s = 0.9. We conducted high-resolution follow-up observations using the Infrared Camera and Spectrograph (IRCS) camera on the Subaru telescope and are able to place an upper limit on the lens flux. From these measurements we are able to exclude all host stars greater than or equal in mass to a G-type dwarf. We conducted a Bayesian analysis with these new flux constraints included as priors resulting in estimates of the masses of the host star and planet. These are M L = 0.34 ± 0.19 M ⊙ and M p =2.5+1.5 -1.4 M jup, respectively. The distance to the system is D L = 4.23 +1.51-1.64 kpc. The projected star–planet separation is a ⊥ = 2.07+0.65-0.77 au. The estimated relative lens-source proper motion, ~7.1 mas yr−1, is fairly high and thus the lens can be better constrained if additional follow-up observations are conducted several years after the event.
Nagakane , M , Lee , C-H , Koshimoto , N , Suzuki , D , Udalski , A , Beaulieu , J P , Sumi , T , Bennett , D P , Bond , I A , Rattenbury , N , Bachelet , E , Dominik , M , Abe , F , Barry , R K , Bhattacharya , A , Donachie , M , Fujii , H , Fukui , A , Hirao , Y , Itow , Y , Kamei , Y , Kondo , I , Li , M C A , Matsubara , Y , Matsuo , T , Miyazaki , S , Muraki , Y , Ranc , C , Shibai , H , Suematsu , H , Sullivan , D J , Tristram , P J , Yamakawa , T , Yonehara , A , Mróz , P , Poleski , R , Skowron , J , Szymański , M K , Soszyński , I , Pietrukowicz , P , Kozłowski , S , Ulaczyk , K , Bramich , D M , Cassan , A , Figuera Jaimes , R J , Horne , K , Hundertmark , M , Mao , S , Menzies , J , Schmidt , R , Snodgrass , C , Steele , I A , Street , R , Tsapras , Y , Wambsganss , J , Jørgensen , U G , Bozza , V , Longã , P , Peixinho , N , Skottfelt , J , Southworth , J , Andersen , M I , Burgdorf , M J , D'Ago , G , Evans , D F , Hinse , T C , Korhonen , H , Rabus , M & Rahvar , S 2019 , ' OGLE-2015-BLG-1649Lb : a gas giant planet around a low-mass dwarf ' , Astronomical Journal , vol. 158 , no. 5 , 212 , pp. 1-9 . https://doi.org/10.3847/1538-3881/ab4881
Copyright © 2019 American Astronomical Society. All rights reserved. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted 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/10.3847/1538-3881/ab4881
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.