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19982026
most citedFirst Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way

1.9k citations · 6k across the 173 of their papers we have counts for

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Showing 2021Show all

28 papers · 1 filter

astro-ph.EP2021★ 25 cited

Systematic KMTNet Planetary Anomaly Search, Paper III: One Wide-Orbit Planet And Two Stellar Binaries

Hanyue Wang, Weicheng Zang, Wei Zhu +36

Only a few wide-orbit planets around old stars have been detected, which limits our statistical understanding of this planet population. Following the systematic search for planeta…

astro-ph.EP2021

KMT-2018-BLG-1988Lb: microlensing super-Earth orbiting a low-mass disk dwarf

Cheongho Han, Andrew Gould, Michael D. Albrow +20

We reexamine high-magnification microlensing events in the previous data collected by the KMTNet survey with the aim of finding planetary signals that were not noticed before. In t…

astro-ph.EP2021★ 12 cited

KMT-2021-BLG-0912Lb: A microlensing super Earth around a K-type star

Cheongho Han, Ian A. Bond, Jennifer C. Yee +55

The light curve of the microlensing event KMT-2021-BLG-0912 exhibits a very short anomaly relative to a single-lens single-source form. We investigate the light curve for the purpo…

astro-ph.EP2021

OGLE-2019-BLG-0468Lb,c: two microlensing giant planets around a G-type star

Cheongho Han, Andrzej Udalski, Chung-Uk Lee +37

With the aim of interpreting anomalous lensing events with no suggested models, we conducted a project of reinvestigating microlensing data in and before the 2019 season. In this w…

astro-ph.GA2021★ 139 cited

Event Horizon Telescope observations of the jet launching and collimation in Centaurus A

Michael Janssen, Heino Falcke, Matthias Kadler +236

Very-long-baseline interferometry (VLBI) observations of active galactic nuclei at millimeter wavelengths have the power to reveal the launching and initial collimation region of e…

astro-ph.HE2021★ 18 cited

The Variability of the Black-Hole Image in M87 at the Dynamical Time Scale

Kaushik Satapathy, Dimitrios Psaltis, Feryal Ozel +235

The black-hole images obtained with the Event Horizon Telescope (EHT) are expected to be variable at the dynamical timescale near their horizons. For the black hole at the center o…

astro-ph.EP2021

Three faint-source microlensing planets detected via resonant-caustic channel

Cheongho Han, Andrzej Udalski, Doeon Kim +32

We conducted a project of reinvestigating the 2017--2019 microlensing data collected by the high-cadence surveys with the aim of finding planets that were missed due to the deviati…

astro-ph.SR2021

Pulsation and Rotation of the EL CVn-type Eclipsing Binary 1SWASP J024743.37-251549.2

Seung-Lee Kim, Jae Woo Lee, Chung-Uk Lee +6

EL CVn-type eclipsing binaries are composed of a massive A-type main-sequence primary star and a hotter B-type secondary star. This paper presents the time-series photometric and a…

astro-ph.EP2021

KMT-2021-BLG-0322: Severe degeneracy between triple-lens and higher-order binary-lens interpretations

Cheongho Han, Andrew Gould, Yuki Hirao +46

We investigate the microlensing event KMT-2021-BLG-0322, for which the light curve exhibits three distinctive sets of caustic-crossing features. It is found that the overall featur…

astro-ph.EP2021★ 5 cited

OGLE-2019-BLG-0304: Competing Interpretations between a Planet-binary Model and a Binary-source + Binary-lens model

Cheongho Han, Andrzej Udalski, Chung-Uk Lee +31

We analyze the microlensing event OGLE-2019-BLG-0304, whose light curve exhibits two distinctive features: a deviation in the peak region and a second bump appearing ~days…

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.EP2021★ 11 cited

KMT-2018-BLG-1743: Planetary Microlensing Event Occurring on Two Source Stars

Cheongho Han, Michael D. Albrow, Sun-Ju Chung +18

We present the analysis of the microlensing event KMT-2018-BLG-1743. The light curve of the event, with a peak magnification , exhibits two anomaly features,…

astro-ph.EP2021★ 48 cited

Systematic KMTNet Planetary Anomaly Search, Paper II: Six New Mass-ratio Planets

Kyu-Ha Hwang, Weicheng Zang, Andrew Gould +62

We apply the automated AnomalyFinder algorithm of Paper I (Zang et al. 2021b) to 2018-2019 light curves from the covered by the six KMTNet prime fields, wi…

gr-qc2021★ 350 cited

Constraints on black-hole charges with the 2017 EHT observations of M87*

Prashant Kocherlakota, Luciano Rezzolla, Heino Falcke +234

Our understanding of strong gravity near supermassive compact objects has recently improved thanks to the measurements made by the Event Horizon Telescope (EHT). We use here the M8…

astro-ph.HE2021★ 89 cited

The Polarized Image of a Synchrotron Emitting Ring of Gas Orbiting a Black Hole

Ramesh Narayan, Daniel C. M. Palumbo, Michael D. Johnson +237

Synchrotron radiation from hot gas near a black hole results in a polarized image. The image polarization is determined by effects including the orientation of the magnetic field i…

astro-ph.GA2021★ 111 cited

Polarimetric properties of Event Horizon Telescope targets from ALMA

Ciriaco Goddi, Ivan Marti-Vidal, Hugo Messias +31

We present the results from a full polarization study carried out with ALMA during the first VLBI campaign, which was conducted in Apr 2017 in the 3mm and 1.3mm bands, in con…

astro-ph.HE2021★ 469 cited

First M87 Event Horizon Telescope Results. VII. Polarization of the Ring

The Event Horizon Telescope Collaboration

In 2017 April, the Event Horizon Telescope (EHT) observed the near-horizon region around the supermassive black hole at the core of the M87 galaxy. These 1.3 mm wavelength observat…

astro-ph.EP2021★ 8 cited

Shortest Microlensing Event with a Bound Planet: KMT-2016-BLG-2605

Yoon-Hyun Ryu, Kyu-Ha Hwang, Andrew Gould +17

KMT-2016-BLG-2605, with planet-host mass ratio , has the shortest Einstein timescale, $t_\e = 3.41\pm 0.13\,$days, of any planetary microlensing event to date. Th…

astro-ph.EP2021★ 18 cited

Three microlensing planets with no caustic-crossing features

Cheongho Han, Andrzej Udalski, Doeon Kim +31

We search for microlensing planets with signals exhibiting no caustic-crossing features, considering the possibility that such signals may be missed due to their weak and featurele…

astro-ph.EP2021★ 15 cited

KMT-2019-BLG-1715: planetary microlensing event with three lens masses and two source stars

Cheongho Han, Andrzej Udalski, Doeone Kim +61

We investigate the gravitational microlensing event KMT-2019-BLG-1715, of which light curve shows two short-term anomalies from a caustic-crossing binary-lensing light curve: one w…

astro-ph.HE2021★ 14 cited

Rapidly-Declining Hostless Type Ia Supernova KSP-OT-201509b from the KMTNet Supernova Program: Transitional Nature and Constraint on Ni Distribution and Progenitor Type

Dae-Sik Moon, Yuan Qi Ni, Maria R. Drout +8

We report the early discovery and multi-color () high-cadence light curve analyses of a rapidly-declining sub-Chandrasekhar Type Ia supernova KSP-OT-201509b (= AT2015cx) from…

astro-ph.EP2021★ 61 cited

Systematic KMTNet Planetary Anomaly Search, Paper I: OGLE-2019-BLG-1053Lb, A Buried Terrestrial Planet

Weicheng Zang, Kyu-Ha Hwang, Andrzej Udalski +69

In order to exhume the buried signatures of "missing planetary caustics" in the KMTNet data, we conducted a systematic anomaly search to the residuals from point-source point-lens…

astro-ph.EP2021★ 5 cited

OGLE-2018-BLG-1428Lb: a Jupiter-mass planet beyond the snow line of a dwarf star

Yun-Hak Kim, Sun-Ju Chung, Andrej Udalski +29

We present the analysis of the microlensing event OGLE-2018-BLG-1428, which has a short-duration ( day) caustic-crossing anomaly. The event was caused by a planetary lens s…

astro-ph.EP2021★ 57 cited

OGLE-2018-BLG-0567Lb and OGLE-2018-BLG-0962Lb: Two Microlensing Planets through Planetary-Caustic Channel

Youn Kil Jung, Cheongho Han, Andrzej Udalski +29

We present the analyses of two microlensing events, OGLE-2018-BLG-0567 and OGLE-2018-BLG-0962. In both events, the short-lasting anomalies were densely and continuously covered by…