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 ( t E ~ 9.1 day) and the small angular Einstein radius ( θ E ~ 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.
Authors
- Michael D. Albrow (ORCID: https://orcid.org/0000-0003-3316-4012)
- Weicheng Zang (ORCID: https://orcid.org/0000-0001-6000-3463)
- Hongjing Yang (ORCID: https://orcid.org/0000-0003-0626-8465)
- Kyu‐Ha Hwang (ORCID: https://orcid.org/0000-0002-9241-4117)
- Byeong-Gon Park (ORCID: https://orcid.org/0000-0002-6982-7722)
- Yoon-Hyun Ryu (ORCID: https://orcid.org/0000-0001-9823-2907)
- Yossi Shvartzvald (ORCID: https://orcid.org/0000-0003-1525-5041)
- Chung‐Uk Lee (ORCID: https://orcid.org/0000-0003-0043-3925)
- Sun‐Ju Chung (ORCID: https://orcid.org/0000-0001-6285-4528)
- Cheongho Han (ORCID: https://orcid.org/0000-0002-2641-9964)
- Youn Kil Jung (ORCID: https://orcid.org/0000-0002-0314-6000)
- In-Gu Shin (ORCID: https://orcid.org/0000-0002-4355-9838)
- Jennifer C. Yee (ORCID: https://orcid.org/0000-0001-9481-7123)
- Richard W. Pogge (ORCID: https://orcid.org/0000-0003-1435-3053)
- Dong-Jin Kim (ORCID: https://orcid.org/0000-0001-5828-6732)
- Andrew Gould
- Doeon Kim
Institutions
- Chungbuk National University (KR)
- University of Canterbury (NZ)
- Korea Astronomy and Space Science Institute (KR)
- Max Planck Institute for Astronomy (DE)
- Center for Astrophysics Harvard & Smithsonian (US)
- The Ohio State University (US)
- Weizmann Institute of Science (IL)
- Tsinghua University (CN)
Publication Details
- Journal
- Astronomy and Astrophysics
- Published
- 2024-11-08
- DOI
- https://doi.org/10.1051/0004-6361/202451620
- Citations
- 2
- Primary Topic
- Astro and Planetary Science
- Type
- article
- Field-Weighted Citation Impact
- 0.66
Funders
- National Science Foundation
- Smithsonian Institution
- National Natural Science Foundation of China
- Korea Astronomy and Space Science Institute
- Ministry of Science and ICT, South Korea
- Korea Research Environment Open Network
- Smithsonian Astrophysical Observatory