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Title: OGLE-2018-BLG-0584 and KMT-2018-BLG-2119: Two microlensing events with two lens masses and two source stars
Aims. We conducted a systematic investigation of the microlensing data collected during the previous observation seasons for the purpose of re-analyzing anomalous lensing events with no suggested plausible models. Methods. We found that two anomalous lensing events, OGLE-2018-BLG-0584 and KMT-2018-BLG-2119, cannot be explained with the usual models based on either a binary-lens single-source (2L1S) or a single-lens binary-source (1L2S) interpretation. We tested the feasibility of explaining the light curves of the events with more sophisticated models by adding either an extra lens (3L1S model) or a source (2L2S model) component to the 2L1S lens system configuration. Results. We find that a 2L2S interpretation explains the light curves of both events well and that for each event there are a pair of solutions resulting from the close and wide degeneracy. For the event OGLE-2018-BLG-0584, the source is a binary composed of two K-type stars and the lens is a binary composed of two M dwarfs. For KMT-2018-BLG-2119, the source is a binary composed of two dwarfs of G and K spectral types and the lens is a binary composed of a low-mass M dwarf and a brown dwarf.  more » « less
Award ID(s):
2108414
PAR ID:
10429519
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
670
ISSN:
0004-6361
Page Range / eLocation ID:
A172
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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