48 citations · 651 across the 92 of their papers we have counts for
97 papers
Enabling Metallicity Measurements of M-dwarf Microlensing Lenses out to the Galactic Bulge
Jiyuan Zhang, Gregory Green, Weicheng Zang +2
We demonstrate that metallicity becomes identifiable for M-dwarf microlensing lenses out to bulge distances when multi-band lens photometry is combined with the angular Einstein ra…
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…
KMT-2025-BLG-2093: Free-Floating Planet Candidate Near the Shore of the Einstein Desert
Yoon-Hyun Ryu, Andrew Gould, Kyu-Ha Hwang +16
We analyze KMT-2025-BLG-2093, with angular Einstein radius , which makes it the second isolated microlens that lies in the ``Einstein Desert'' ($9…
Measuring Asteroid Rotation Periods Using the KMTNet Bulge Survey Data
Haitao Huang, Hongjing Yang, Chung-Uk Lee +6
Since 2015, the Korea Microlensing Telescope Network (KMTNet) has conducted high-cadence, near-continuous observations of the Galactic bulge for nearly nine months each year from t…
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-(…
A Minute-Cadence Deep Bulge Survey: First Data Release of DREAMS
Hongjing Yang, Weicheng Zang, Francisco Valdes +31
The DECam Rogue Earths and Mars Survey (DREAMS), a NOIRLab survey program, has been conducting a three-year survey covering a 5 deg area in the Galactic bulge (roughly spanning…
Systematic KMTNet Planetary Anomaly Search. XIII. Complete Sample of 2021 Prime Field Planets
In-Gu Shin, Jennifer C. Yee, Weicheng Zang +39
The Systematic KMTNet Planetary Anomaly Search series was conducted using the KMTNet data archived from to . From this first phase of the series, we reported a total o…
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…
KMT-2025-BLG-1314 and KMT-2025-BLG-1392: two microlensing planetary/brown-dwarf candidates analyzed with differentiable code
Haibin Ren, Weicheng Zang, Wei Zhu +20
Analysis of binary-lens microlensing events typically requires intensive computation because of the multimodal and complex posterior distributions. With the recent development of t…
KMT-2024-BLG-3237: Another Free-Floating Planet Candidate with Angular Einstein Radius Measurement
Tanagodchaporn Inyanya, Youn Kil Jung, Hongjing Yang +13
Planet formation theories suggest the presence of free-floating planets (FFPs) that are ejected from their formation sites. While these planets emit very little light, they can be…
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…
Four Cold Super-Jupiters Revealed by Extended and Complex Microlensing Signals
Cheongho Han, Chung-Uk Lee, Michael D. Albrow +18
We present the analysis of four microlensing events, KMT-2020-BLG-0202, KMT-2022-BLG-1551, KMT-2023-BLG-0466, and KMT-2025-BLG-0121, which exhibit extended and complex anomalies in…
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…
KMT-2025-BLG-1616Lb: First Microlensing Bound Planet From DREAMS
Hongjing Yang, Weicheng Zang, Yoon-Hyun Ryu +60
We present observations and analysis of the bound planetary microlensing event KMT-2025-BLG-1616. The planetary signal was captured by the Korea Microlensing Telescope Network (KMT…
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…