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20182026
most citedAn isolated mass gap black hole or neutron star detected with astrometric microlensing

140 citations · 1k across the 65 of their papers we have counts for

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12 papers · 1 filter

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.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.SR2022★ 6 cited

Precision measurement of a brown dwarf mass in a binary system in the microlensing event OGLE-2019-BLG-0033/MOA-2019-BLG-035

A. Herald, A. Udalski, V. Bozza +89

Context. Brown dwarfs are poorly understood transition objects between stars and planets, with several competing mechanisms having been proposed for their formation. Mass measureme…

astro-ph.SR2022

An Isolated Stellar-Mass Black Hole Detected Through Astrometric Microlensing

Kailash C. Sahu, Jay Anderson, Stefano Casertano +90

We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry…

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★ 2 cited

OGLE-2014-BLG-0962 and the First Statistical Validation of Bayesian Priors for Galactic Microlensing

Yutong Shan, Jennifer C. Yee, Andrzej Udalski +46

OGLE-2014-BLG-0962 (OB140962) is a stellar binary microlensing event that was well-covered by observations from the Spitzer satellite as well as ground-based surveys. Modelling yie…