collaborators

19 papers

astro-ph.EP2026

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…

astro-ph.EP2026

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…

astro-ph.EP2026

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…

astro-ph.EP2025

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…

astro-ph.SR2025

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…

astro-ph.CO2025

Eppur non si trovano: Comments on the Primordial Black Hole Limits in the Galactic Halo

P. Mróz, A. Udalski, M. K. Szymański +13

In a recent arXiv post, Hawkins & Garcia-Bellido raised doubts on the results of 20-yr long OGLE photometric monitoring, which did not find a large number of gravitational microlen…