In:
Astronomy & Astrophysics, EDP Sciences, Vol. 649 ( 2021-5), p. A90-
Abstract:
Aims. We aim to find missing microlensing planets hidden in the unanalyzed lensing events of previous survey data. Methods. For this purpose, we conducted a systematic inspection of high-magnification microlensing events, with peak magnifications of A peak ≳ 30, in the data collected from high-cadence surveys in and before the 2018 season. From this investigation, we identified an anomaly in the lensing light curve of the event KMT-2018-BLG-1025. The analysis of the light curve indicates that the anomaly is caused by a very low mass-ratio companion to the lens. Results. We identify three degenerate solutions, in which the ambiguity between a pair of solutions (solutions B) is caused by the previously known close–wide degeneracy, and the degeneracy between these and the other solution (solution A) is a new type that has not been reported before. The estimated mass ratio between the planet and host is q ~ 0.8 × 10 −4 for solution A and q ~ 1.6 × 10 −4 for solutions B. From the Bayesian analysis conducted with measured observables, we estimate that the masses of the planet and host and the distance to the lens are ( M p , M h , D L ) ~ (6.1 M ⊕ , 0.22 M ⊙ , 6.7 kpc) for solution A and ~(4.4 M ⊕ , 0.08 M ⊙ , 7.5 kpc) for solutions B. The planet mass is in the category of a super-Earth regardless of the solutions, making the planet the eleventh super-Earth planet, with masses lying between those of Earth and the Solar System’s ice giants, which were discovered by microlensing.
Type of Medium:
Online Resource
ISSN:
0004-6361
,
1432-0746
DOI:
10.1051/0004-6361/202039817
Language:
English
Publisher:
EDP Sciences
Publication Date:
2021
detail.hit.zdb_id:
1458466-9
SSG:
16,12
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