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20072026
most citedA Neptune-mass Free-floating Planet Candidate Discovered by Microlensing Surveys

94 citations · 1.8k across the 151 of their papers we have counts for

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astro-ph.SR2026

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…

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.SR2025

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…

astro-ph.SR2025

KMT-2022-BLG-0086: Another binary-lens binary-source microlensing event

Sun-Ju Chung, Kyu-Ha Hwang, Jennifer C. Yee +40

We present the analysis of a microlensing event KMT-2022-BLG-0086 of which the overall light curve is not described by a binary-lens single-source (2L1S) model, which suggests the…

astro-ph.SR2024

KMT-2021-BLG-0284, KMT-2022-BLG-2480, and KMT-2024-BLG-0412: Three microlensing events involving two lens masses and two source stars

Cheongho Han, Andrzej Udalski, Ian A. Bond +59

We carried out a project involving the systematic analysis of microlensing data from the Korea Microlensing Telescope Network survey. The aim of this project is to identify lensing…

astro-ph.SR2024

Microlensing brown-dwarf companions in binaries detected during the 2022 and 2023 seasons

Cheongho Han, Ian A. Bond, Andrzej Udalski +63

Building on previous works to construct a homogeneous sample of brown dwarfs in binary systems, we investigate microlensing events detected by the Korea Microlensing Telescope Netw…

astro-ph.SR2024

OGLE-2018-BLG-0971, MOA-2023-BLG-065, and OGLE-2023-BLG-0136: Microlensing events with prominent orbital effects

Cheongho Han, Andrzej Udalski, Ian A. Bond +60

We undertake a project to reexamine microlensing data gathered from high-cadence surveys. The aim of the project is to reinvestigate lensing events with light curves exhibiting int…

astro-ph.SR2023

Brown dwarf companions in binaries detected from the 2021 season high-cadence microlensing surveys

Cheongho Han, Youn Kil Jung, Ian A. Bond +45

As a part of the project aiming to build a homogeneous sample of binary-lens (2L1S) events containing brown-dwarf (BD) companions, we investigate the 2021 season microlensing data…

astro-ph.SR2023★ 5 cited

Probable brown dwarf companions detected in binary microlensing events during the 2018-2020 seasons of the KMTNet survey

Cheongho Han, Youn Kil Jung, Doeon Kim +48

We inspect the microlensing data of the KMTNet survey collected during the 2018--2020 seasons in order to find lensing events produced by binaries with brown-dwarf companions. In o…

astro-ph.SR2023★ 2 cited

OGLE-2017-BLG-1038: A Possible Brown-dwarf Binary Revealed by Spitzer Microlensing Parallax

Amber Malpas, Michael D. Albrow, Jennifer C. Yee +41

We report the analysis of microlensing event OGLE-2017-BLG-1038, observed by the Optical Gravitational Lensing Experiment, Korean Microlensing Telescope Network, and Spitzer telesc…

astro-ph.SR2023★ 6 cited

KMT-2021-BLG-1122L: The first microlensing triple stellar system

Cheongho Han, Youn Kil Jung, Andrew Gould +19

We systematically inspect the microlensing data acquired by the KMTNet survey during the previous seasons in order to find anomalous lensing events for which the anomalies in the l…

astro-ph.SR2022★ 14 cited

OGLE-2018-BLG-0584 and KMT-2018-BLG-2119: two microlensing events with two lens masses and two source stars

Cheongho Han, Andrzej Udalski, Youn Kil Jung +34

We conduct a systematic investigation of the microlensing data collected during the previous observation seasons for the purpose of reanalyzing anomalous lensing events with no sug…

astro-ph.SR2022★ 9 cited

Brown-dwarf companions in microlensing binaries detected during the 2016--2018 seasons

Cheongho Han, Yoon-Hyun Ryu, In-Gu Shin +60

With the aim of finding microlensing binaries containing brown-dwarf (BD) companions, we investigate the microlensing survey data collected during the 2016--2018 seasons. For this…

astro-ph.SR2021★ 2 cited

Using Source Proper Motion to Validate Terrestrial Parallax: OGLE-2019-BLG-1058

In-Gu Shin, Jennifer C. Yee, Kyu-Ha Hwang +30

We show that because the conditions for producing terrestrial microlens parallax (TPRX; i.e., a nearby disk lens) will also tend to produce a large lens-source relative proper moti…

astro-ph.SR2021★ 11 cited

KMT-2019-BLG-0797: binary-lensing event occurring on a binary stellar system

Cheongho Han, Chung-Uk Lee, Yoon-Hyun Ryu +18

We analyze the microlensing event KMT-2019-BLG-0797. The light curve of the event exhibits two anomalous features from a single-lens single-source model, and we aim to reveal the n…

astro-ph.SR2020★ 9 cited

OGLE-2018-BLG-1269Lb: A Jovian Planet With A Bright, Host

Youn Kil Jung, Andrew Gould, Andrzej Udalski +54

We report the discovery of a planet in the microlensing event OGLE-2018-BLG-1269, with planet-host mass ratio , i.e., times smaller than the Jupiter/Su…

astro-ph.SR2019★ 12 cited

Candidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii

Cheongho Han, Chung-Uk Lee, Andrzej Udalski +62

Short-timescale microlensing events are likely to be produced by substellar brown dwarfs (BDs), but it is difficult to securely identify BD lenses based on only event timescales $t…

astro-ph.SR2019★ 15 cited

Spitzer Microlensing parallax reveals two isolated stars in the Galactic bulge

Weicheng Zang, Yossi Shvartzvald, Tianshu Wang +90

We report the mass and distance measurements of two single-lens events from the 2017 Spitzer microlensing campaign. The ground-based observations yield the detection of finite-sour…

astro-ph.SR2019★ 3 cited

OGLE-2018-BLG-0022: First Prediction of an Astrometric Microlensing Signal from a Photometric Microlensing Event

Cheongho Han, Ian A. Bond, Andrzej Udalski +63

In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with t…

astro-ph.SR2019★ 17 cited

OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing

Shun-Sheng Li, Weicheng Zang, Andrzej Udalski +102

We present the analysis of the event OGLE-2017-BLG-1186 from the 2017 Spitzer microlensing campaign. This is a remarkable microlensing event because its source is photometrically b…

astro-ph.SR2019★ 12 cited

Spitzer Microlensing of MOA-2016-BLG-231L : A Counter-Rotating Brown Dwarf Binary in the Galactic Disk

Sun-Ju Chung, Andrew Gould, Jan Skowron +60

We analyze the binary microlensing event MOA-2016-BLG-231, which was observed from the ground and from Spitzer. The lens is composed of very low-mass brown dwarfs (BDs) with $M_1 =…

astro-ph.SR2019★ 3 cited

OGLE-2016-BLG-0156: Microlensing Event With Pronounced Microlens-Parallax Effects Yielding Precise Lens Mass Measurement

Youn Kil Jung, Cheongho Han, Ian A. Bond +53

We analyze the gravitational binary-lensing event OGLE-2016-BLG-0156, for which the lensing light curve displays pronounced deviations induced by microlens-parallax effects. The li…

astro-ph.SR2018★ 8 cited

OGLE-2017-BLG-0039: Microlensing Event with Light from the Lens Identified from Mass Measurement

C. Han, Y. K. Jung, A. Udalski +58

We present the analysis of the caustic-crossing binary microlensing event OGLE-2017-BLG-0039. Thanks to the very long duration of the event, with an event time scale $t_{\rm E}\sim…

astro-ph.SR2018★ 5 cited

KMT-2016-BLG-2052L: Microlensing Binary Composed of M Dwarfs Revealed from a Very Long Time-scale Event

Cheongho Han, Youn Kil Jung, Yossi Shvartzvald +26

We present the analysis of a binary microlensing event KMT-2016-BLG-2052, for which the lensing-induced brightening of the source star lasted for 2 seasons. We determine the lens m…