705 citations · 12k across the 299 of their papers we have counts for
314 papers
Two Low-Mass-Ratio Microlensing Planets from High-Magnification Events: KMT-2021-BLG-0247 and MOA-2023-BLG-169
Kansuke Nunota, Andrew Gould, Takahiro Sumi +56
We present an analysis of two planetary microlensing events, KMT-2021-BLG-0247 and MOA-2023-BLG-169, both of which exhibit high magnifications and low planet--host mass ratios, but…
KMT-2026-BLG-0083L: A Two-Jovian-Planet System Orbiting an M Dwarf Discovered by Microlensing
Cheongho Han, Chung-Uk Lee, Zhixing Li +65
We present the analysis of the microlensing event KMT-2026-BLG-0083, which was independently detected by the KMTNet, OGLE, and PRIME surveys and also monitored by the DREAMS survey…
KMT-2025-BLG-0975Lb and KMT-2025-BLG-1160Lb: Two Uranus-Mass Planets Beyond the Snow Line Discovered by Microlensing
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +27
We present the analysis of two planetary microlensing events, KMT-2025-BLG-0975 and KMT-2025-BLG-1160, discovered during the 2025 Galactic bulge microlensing season through high-ca…
Four Cold Giant Planets Discovered by High-Cadence Microlensing Surveys
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +52
We report the discovery of four cold giant planets identified through the analysis of microlensing events detected by high-cadence surveys: OGLE-2016-BLG-0261, KMT-2025-BLG-0026, K…
Incorporating physical source parameters into microlensing modeling
Mateusz J. Mróz, Radosław Poleski, Andrzej Udalski +14
Modeling of complex microlensing events suffers from many difficult-to-disentangle degeneracies. This is especially the case for orbital motion of the source in a binary system, th…
Four-Body Gravitational Microlensing Events Involving Both a Binary Lens and a Binary Source
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +31
We present detailed analyses of three anomalous microlensing events--KMT-2021-BLG-0209, KMT-2021-BLG-0901, and OGLE-2025-BLG-0356--identified from a systematic re-examination of KM…
Mass Production of 2023 KMTNet Microlensing Planets. III: Three Planets from the Subprime Field
Hongyu Li, Zhixing Li, Weicheng Zang +56
To complete the analysis of the 2023 KMTNet subprime-field microlensing planetary events identified by its AlertFinder system, we present the analysis of six events, KMT-2023-BLG-(…
Candidate Microlensing Brown Dwarfs in Binary Lens Systems from the 2023--2025 Observing Seasons
Cheongho Han, Andrzej Udalski, Ian A. Bond +62
We present detailed light-curve analyses of ten binary-lens microlensing events observed during the 2023--2025 seasons and selected as candidates for hosting brown-dwarf companions…
Mass Production of 2023 KMTNet Microlensing Planets. II: Two Planets and A Brown Dwarf
Zhixing Li, Hongyu Li, Weicheng Zang +63
To expand the homogeneous microlensing planetary sample of the Korea Microlensing Telescope Network (KMTNet), we investigate six planetary candidates identified by the AnomalyFinde…
Mass Production of 2023 KMTNet Microlensing Planets I: Low Mass Ratio
Yoon-Hyun Ryu, Andrzej Udalski, Hongjing Yang +34
We initiate the systematic search for planets in the 2023 data of the Korea Microlensing Telescope Network (KMTNet), focusing on those planets found by the KMTNet AnomalyFinder wit…
Two Low Mass-Ratio Microlensing Planets and Two Types of Central-Resonant Degeneracy
Yuchen Tang, Weicheng Zang, Yoon-Hyun Ryu +39
We present observations and analysis of two low planet/host mass-ratio () microlensing planets discovered in high-magnification events. KMT-2025-BLG-0811Lb has $q \sim 4.5 \time…
Three Saturn-mass Microlensing Planets Identified through Signals from Peripheral-caustic Perturbations
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +63
We present the discovery and analysis of three microlensing planets identified through brief positive anomalies on the wings of their light curves. The events, KMT-2021-BLG-0852, K…
KMT-2016-BLG-1337L: A Saturn-mass planet orbiting within a binary system of low-mass stars
Cheongho Han, Chung-Uk Lee, Ian A. Bond +55
We report the discovery and characterization of a planetary companion in the microlensing event KMT-2016-BLG-1337, which was produced by a binary system of low-mass stars. The ligh…
A Newly Identified Degeneracy Keeps the Planetary Interpretation Viable for OGLE-2011-BLG-0950
Jiyuan Zhang, Weicheng Zang, Andrzej Udalski +12
The microlensing event OGLE-2011-BLG-0950 exhibits the well-known ``Planet/Binary'' degeneracy, in which distinct lens configurations produce similar light curves but imply substan…
A free-floating-planet microlensing event caused by a Saturn-mass object
Subo Dong, Zexuan Wu, Yoon-Hyun Ryu +39
A population of free-floating planets is known from gravitational microlensing surveys. None have a directly measured mass, owing to a degeneracy with the distance, but the populat…
Four Giant Planets from 2024 KMTNet Microlensing Campaign
Cheongho Han, Andrzej Udalski, Ian A. Bond +56
In this work, we present analyses of four newly discovered planetary microlensing events from the 2024 KMTNet survey season: KMT-2024-BLG-0176, KMT-2024-BLG-0349, KMT-2024-BLG-1870…
Six binary brown dwarf candidates identified by microlensing
Cheongho Han, Chung-Uk Lee, Ian A. Bond +57
In this study, we analyze microlensing events from the 2023 and 2024 observing seasons to identify cases likely caused by binary systems composed of BDs. By applying criteria that…
A Comprehensive Analysis of Three Microlensing Planet Candidates with the Planet/Binary Degeneracy
Jiyuan Zhang, Weicheng Zang, Yoon-Hyun Ryu +65
We present observations and analyses of three high-magnification microlensing events: KMT-2022-BLG-0954, KMT-2024-BLG-0697, and MOA-2024-BLG-018. All three exhibit the "Planet/Bina…
Three binary-source binary-lens microlensing events from the 2024 microlensing campaign
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +27
We investigated microlensing events detected by the OGLE and KMTNet surveys during the 2024 observing season, focusing on those that exhibit very complex anomaly features. Through…
Six microlensing planets detected via sub-day signals during the 2023 -- 2024 season
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +58
We present analyses of six microlensing events: KMT-2023-BLG-0548, KMT-2023-BLG-0830, KMT-2023-BLG-0949, KMT-2024-BLG-1281, KMT-2024-BLG-2059, and KMT-2024-BLG-2242. These were ide…
Four binary microlenses with directly measured masses
Cheongho Han, Andrzej Udalski, Chung-Uk Lee +58
We investigated binary lens events from the 2022-2024 microlensing surveys, aiming to identify events suitable for lens mass measurements. We focused on two key light curve feature…
Microlensing optical depth, event rate, and limits on compact objects in dark matter based on 20 yr of OGLE observations of the Small Magellanic Cloud
P. Mróz, A. Udalski, M. K. Szymański +12
Some previous studies have suggested that massive and intermediate-mass primordial black holes (PBHs) could comprise a substantial fraction of dark matter in the Universe. Such bla…
HST pre-imaging of a free-floating planet candidate microlensing event
Mateusz Kapusta, Przemek Mroz, Yoon-Hyun Ryu +33
High-cadence microlensing observations uncovered a population of very short-timescale microlensing events, which are believed to be caused by the population of free-floating planet…
MOA-2022-BLG-091Lb and KMT-2024-BLG-1209Lb: Microlensing planets detected through weak caustic-crossing signals
Cheongho Han, Chung-Uk Lee, Andrzej Udalski +66
The light curves of the microlensing events MOA-2022-BLG-091 and KMT-2024-BLG-1209 exhibit anomalies with very similar features. These anomalies appear near the peaks of the light…