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Title: KMT-2024-BLG-1044L: A sub-Uranus microlensing planet around a host at the star–brown dwarf mass boundary
Aims.We analysed microlensing data to uncover the nature of the anomaly that appeared near the peak of the short-timescale microlensing event KMT-2024-BLG-1044. Despite the anomaly’s brief duration of less than a day, it was densely observed through high-cadence monitoring conducted by the KMTNet survey. Methods.Detailed modelling of the light curve confirmed the planetary origin of the anomaly and revealed two possible solutions, due to an inner–outer degeneracy. The two solutions provide different measured planet parameters: (s,q)inner= [1.0883 ± 0.0027, (3.125 ± 0.248) × 10−4] for the inner solutions and (s,q)outer= [1.0327 ± 0.0054, (3.350 ± 0.316) × 10−4] for the outer solutions. Results.Using Bayesian analysis with constraints provided by the short event timescale (tE~ 9.1 day) and the small angular Einstein radius (θE~ 0.16 mas for the inner solution and ~ 0.10 mas for the outer solutio), we determined that the lens is a planetary system consisting of a host near the boundary between a star and a brown dwarf and a planet with a mass lower than that of Uranus. The discovery of the planetary system highlights the crucial role of the microlensing technique in detecting planets that orbit substellar brown dwarfs or very low-mass stars.  more » « less
Award ID(s):
2108414
PAR ID:
10654678
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Astronomy & Astrophysics
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
692
ISSN:
0004-6361
Page Range / eLocation ID:
A106
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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