activity
20152026
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 · 7.7k across the 85 of their papers we have counts for

collaborators

87 papers

astro-ph.GA2026

Dynamics and geometry of the inner sub-parsec-scale jet in 3C 279 observed with the Event Horizon Telescope

Hendrik Mueller, Sebastiano D. von Fellenberg, Ai-Ling Zeng +275

The 2021 Event Horizon Telescope observations resolve the innermost jet region of the blazar 3C279 with unprecedented detail. The reconstructed images consistently reveal a compact…

astro-ph.HE2026

Broadband multiwavelength properties of the archetypal blazar 3C 279 during the 2017 Event Horizon Telescope campaign

G. Principe, J. C. Algaba, E. Aviano +529

The archetypal blazar 3C 279 hosts a prominent relativistic jet and exhibits strong broadband variability across the electromagnetic spectrum. In April 2017, the Event Horizon Tele…

astro-ph.GA2026

Full-polarization millimeter wavelength variability of Sagittarius A* during the 2018 EHT campaign

Ezequiel Albentosa-Ruiz, Jasmin E. Washington, Nicola Marchili +272

Sagittarius A* (Srg A*), the supermassive black hole at the center of the Milky Way, provides a unique laboratory to study accretion dynamics and plasma processes near the event ho…

astro-ph.IM2026

Verification of the Polarimetric Capability of the East Asia VLBI Network

Yunjeong Lee, Jongho Park, Do-Young Byun +10

The East Asia VLBI Network (EAVN) has recently enabled dual-polarization observations at and . We present the first systematic verification of its polarimetr…

astro-ph.GA2026

A Unified Origin of Faraday Rotation toward 3C 84: The Circumnuclear Ambient Medium within the Parsec-Scale Bondi Radius of the Host Galaxy NGC 1275

Minchul Kam, Jongho Park, Sascha Trippe +11

We present multi-frequency polarimetric observations of 3C 84 obtained with the Korean VLBI Network at 43-141 GHz, the Very Long Baseline Array at 43 GHz, and the High Sensitivity…

astro-ph.HE2026★ 1 cited

Transverse Oscillations and Wave Propagation in the Magnetically Dominated M87 Jet

Hyunwook Ro, Motoki Kino, Kazuhiro Hada +6

We present an in-depth analysis of transverse oscillations in the M87 jet, as identified in our previous study (Ro et al. 2023a), which reported oscillatory patterns with a charact…

astro-ph.HE2026★ 1 cited

Locating the missing large-scale emission in the jet of M87* with short EHT baselines

Boris Georgiev, Paul Tiede, Sebastiano D. von Fellenberg +280

In Very-Long Baseline Interferometric arrays, nearly co-located stations probe the largest scales and typically cannot resolve the observed source. In the absence of large-scale st…

astro-ph.HE2026★ 1 cited

Ring Asymmetry and Spin in M87*

Vadim Bernshteyn, Nicholas S. Conroy, Michi Bauböck +263

Event Horizon Telescope (EHT) images of the supermassive black hole M87* depict an asymmetric ring of emission. General relativistic magnetohydrodynamic (GRMHD) models of M87* and…

astro-ph.HE2025★ 4 cited

Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations

Saurabh, Hendrik Müller, Sebastiano D. von Fellenberg +282

We investigate the presence and spatial characteristics of the jet base emission in M87* at 230 GHz, enabled by the enhanced uv coverage in the 2021 Event Horizon Telescope (EHT) o…

astro-ph.HE2025

Helical Magnetic Field in the Acceleration--Collimation Zone of the M87 Jet

Jongho Park, Kazuya Takahashi, Kenji Toma +10

Relativistic jets from supermassive black holes are expected to be magnetically launched and guided, with magnetic energy systematically converted to bulk kinetic energy throughout…

astro-ph.IM2025

Bayesian polarization calibration and imaging in very long baseline interferometry

Jong-Seo Kim, Jakob Roth, Jongho Park +6

Extracting polarimetric information from very long baseline interferometry (VLBI) data is demanding but vital for understanding the synchrotron radiation process and the magnetic f…

astro-ph.GA2025

Monitoring of 3C 286 with ALMA, IRAM, and SMA from 2006 to 2025: Stability, Synchrotron Ages, and Frequency-Dependent Polarization Attributed to Core-Shift

Minchul Kam, Hiroshi Nagai, Motoki Kino +23

We present the results of multi-frequency monitoring of the radio quasar 3C 286, conducted using three instruments: ALMA at 91.5, 103.5, 233.0, and 343.4 GHz, the IRAM 30-m Telesco…

astro-ph.HE2025

Constraining the Mass of a Hypothetical Secondary Black Hole in M87 with the NANOGrav 15-Year Data Set

Motoki Kino, Masahiro Nagashima, Hyunwook Ro +3

Galaxy mergers, each hosting a supermassive black hole (SMBH), are thought to form SMBH binaries. Motivated by recent observations from the East Asian VLBI Network (EAVN) showing p…

astro-ph.HE2025★ 4 cited

Origin of the ring ellipticity in the black hole images of M87*

Rohan Dahale, Ilje Cho, Kotaro Moriyama +273

We investigate the origin of the elliptical ring structure observed in the images of the supermassive black hole M87*, aiming to disentangle contributions from gravitational, astro…

astro-ph.GA2025★ 8 cited

First polarization study of the M87 jet and active galactic nuclei at submillimeter wavelengths with ALMA

Ciriaco Goddi, Douglas F. Carlos

We present full-polarization observations at mm (345 GHz) conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) toward Messier 87 (M87) and seven other r…

astro-ph.IM2025★ 1 cited

Enhanced imaging of M87*: Simulations with the EHT and extended-KVN

Ilje Cho, Jongho Park, Do-Young Byun +16

The Event Horizon Telescope (EHT) has successfully revealed the shadow of the supermassive black hole, M87*, with an unprecedented angular resolution of approximately 20 uas at 230…

astro-ph.HE2025★ 10 cited

The putative center in NGC 1052

Anne-Kathrin Baczko, Matthias Kadler, Eduardo Ros +284

Many active galaxies harbor powerful relativistic jets, however, the detailed mechanisms of their formation and acceleration remain poorly understood. To investigate the area of je…

astro-ph.HE2025★ 1 cited

Gamma-ray flares from the jet of the blazar CTA 102 in 2016-2018

Sanghyun Kim, Sang-Sung Lee, Juan Carlos Algaba +16

CTA 102 is a -ray bright blazar that exhibited multiple flares in observations by the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope during the period of 2016…

astro-ph.HE2025★ 13 cited

A multi-frequency study of sub-parsec jets with the Event Horizon Telescope

Jan Röder, Maciek Wielgus, Andrei P. Lobanov +287

The 2017 observing campaign of the Event Horizon Telescope (EHT) delivered the first very long baseline interferometry (VLBI) images at the observing frequency of 230 GHz, leading…

astro-ph.GA2024★ 2 cited

Demographics of black holes at 100 R scales: accretion flows, jets, and shadows

Dhanya G. Nair, Neil M. Nagar, Venkatessh Ramakrishnan +87

Using the Event Horizon Telescope (EHT), the gravitationally lensed rings around the supermassive black holes (SMBHs) in Messier 87 (M87) and Sagittarius A* (Sgr A*) have now been…

astro-ph.IM2024★ 30 cited

First Very Long Baseline Interferometry Detections at 870μm

Alexander W. Raymond, Sheperd S. Doeleman, Keiichi Asada +276

The first very long baseline interferometry (VLBI) detections at 870m wavelength (345GHz frequency) are reported, achieving the highest diffraction-limited angular resolutio…

astro-ph.HE2024★ 17 cited

Discovery of Limb Brightening in the Parsec-scale Jet of NGC 315 through Global Very Long Baseline Interferometry Observations and Its Implications for Jet Models

Jongho Park, Guang-Yao Zhao, Masanori Nakamura +19

We report the first observation of the nearby giant radio galaxy NGC 315 using a global VLBI array consisting of 22 radio antennas located across five continents, including high-se…

astro-ph.HE2024

Mapping the distribution of the magnetic field strength along the NGC 315 jet

Motoki Kino, Hyunwook Ro, Masaaki Takahashi +4

We study magnetic field strengths along the jet in NGC~315. First, we estimated the angular velocity of rotation in the jet magnetosphere by comparing the measured velocity profile…

astro-ph.HE2024★ 11 cited

Jet Collimation and Acceleration in the Flat Spectrum Radio Quasar 1928+738

Kunwoo Yi, Jongho Park, Masanori Nakamura +2

Using time-resolved multifrequency Very Long Baseline Array data and new KaVA (KVN and VERA Array) observations, we study the structure and kinematics of the jet of the flat spectr…