Spitzer microlensing parallax reveals two isolated stars in the Galactic bulge
View/
Date
01/03/2020Metadata
Show full item recordAltmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
We report the mass and distance measurements of two single-lens events from the 2017 Spitzer microlensing campaign. The ground-based observations yield the detection of finite-source effects, and the microlens parallaxes are derived from the joint analysis of ground-based observations and Spitzer observations. We find that the lens of OGLE-2017-BLG-1254 is a 0.60 ± 0.03 M ⊙ star with D LS = 0.53 ± 0.11 kpc, where D LS is the distance between the lens and the source. The second event, OGLE-2017-BLG-1161, is subject to the known satellite parallax degeneracy, and thus is either a 0.51-0.10+0.12 M⊙ star with D LS = 0.40 ± 0.12 kpc or a 0.38-0.12+0.13 M⊙ star with D LS = 0.53 ± 0.19 kpc. Both of the lenses are therefore isolated stars in the Galactic bulge. By comparing the mass and distance distributions of the eight published Spitzer finite-source events with the expectations from a Galactic model, we find that the Spitzer sample is in agreement with the probability of finite-source effects occurring in single-lens events.
Citation
Zang , W , Shvartzvald , Y , Wang , T , Udalski , A , Lee , C-U , Sumi , T , Skottfelt , J , Li , S-S , Mao , S , Zhu , W , Yee , J C , Calchi Novati , S , Beichman , C A , Bryden , G , Carey , S , Gaudi , B S , Henderson , C B , Mróz , P , Skowron , J , Poleski , R , Szymański , M K , Soszyński , I , Pietrukowicz , P , Kozłowski , S , Ulaczyk , K , Rybicki , K A , Iwanek , P , Bachelet , E , Christie , G , Green , J , Hennerley , S , Maoz , D , Natusch , T , Pogge , R W , Street , R A , Tsapras , Y , Albrow , M D , Chung , S-J , Gould , A , Han , C , Hwang , K-H , Jung , Y K , Ryu , Y-H , Shin , I-G , Cha , S-M , Kim , D-J , Kim , H-W , Kim , S-L , Lee , D-J , Lee , Y , Park , B-G , Pogge , R W , Bond , I A , Abe , F , Barry , R , Bennett , D P , Bhattacharya , A , Donachie , M , Fukui , A , Hirao , Y , Itow , Y , Kondo , I , Koshimoto , N , Li , M C A , Matsubara , Y , Muraki , Y , Miyazaki , S , Nagakane , M , Ranc , C , Rattenbury , N J , Suematsu , H , Sullivan , D J , Suzuki , D , Tristram , P J , Yonehara , A , Dominik , M , Hundertmark , M , Jørgensen , U G , Rahvar , S , Sajadian , S , Snodgrass , C , Bozza , V , Burgdorf , M J , Evans , D F , Figuera Jaimes , R , Fujii , Y I , Mancini , L , Longa-Peña , P , Helling , C , Peixinho , N , Rabus , M , Southworth , J , Unda-Sanzana , E & von Essen , C 2020 , ' Spitzer microlensing parallax reveals two isolated stars in the Galactic bulge ' , Astrophysical Journal , vol. 891 , no. 1 , 3 . https://doi.org/10.3847/1538-4357/ab6ff8
Publication
Astrophysical Journal
Status
Peer reviewed
ISSN
0004-637XType
Journal article
Rights
Copyright © 2020 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 final published version of the work, which was originally published at https://doi.org/10.3847/1538-4357/ab6ff8
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.